Citation Nr: 1014043 Decision Date: 04/13/10 Archive Date: 04/29/10 DOCKET NO. 05-07 005 ) DATE ) ) On appeal from the Department of Veterans Affairs Regional Office in Nashville, Tennessee THE ISSUES 1. Entitlement to service connection for the residuals of the removal of malignant melanoma from the left arm, and a lentiginous compound nevus from the chest, claimed as skin cancer, as due to exposure to herbicide agents. 2. Entitlement to service connection for hypertension, to include as secondary to service-connected diabetes mellitus. 3. Entitlement to service connection for obstructive sleep apnea, to include as secondary to service-connected diabetes mellitus. 4. Entitlement to service connection for restless leg syndrome, to include as secondary to service-connected diabetes mellitus. 5. Entitlement to a higher initial rating than 20 percent for diabetes mellitus, including whether separate compensable ratings are warranted for diabetic complications. 6. Entitlement to a higher initial disability rating for peripheral neuropathy of the right lower extremity than 0 percent for the period from June 18, 2005, and higher than 10 percent from May 2, 2008. 7. Entitlement to a higher initial disability rating for peripheral neuropathy of the left lower extremity than 0 percent for the period from June 18, 2005, and higher than 10 percent from May 2, 2008. REPRESENTATION Appellant represented by: Dennis Pash, Attorney WITNESSES AT HEARING ON APPEAL The Veteran (Appellant) and his spouse ATTORNEY FOR THE BOARD Simone Krembs, Counsel INTRODUCTION The Veteran served on active duty from April 1969 to January 1972. This matter comes before the Board of Veterans' Appeals (Board) from a February 2004 rating decision of a Department of Veterans Affairs (VA) Regional Office (RO) that granted service connection and assigned a 20 percent initial disability rating for diabetes mellitus, and denied service connection for skin cancer (as due to exposure to herbicide agents), sleep apnea, hypertension, and restless leg syndrome, each to include as secondary to service-connected diabetes mellitus. The Veteran testified before the Board in a November 2005 hearing that was held at the RO. In February 2007, the Board remanded the claims for additional development. The Judge before whom the appellant testified in November 2005 is no longer employed by the Board. In January 2009, the appellant was informed of such and was offered an opportunity to have another Board hearing. In a response received later that month, the appellant requested an another Board hearing. He and his spouse testified before the Board in January 2010 at a personal hearing that was held in Nashville, Tennessee. A transcript of that hearing has been made a part of the record. During the pendency of the appeal for an increased disability rating for service-connected diabetes mellitus, in a July 2008 rating decision, the RO granted separate disability ratings for the diabetic complications of peripheral neuropathy of the right and left lower extremities. Because this grant of separate ratings for peripheral neuropathy and assignment of initial ratings grew out of the issue of increased rating for diabetes, an issue already on appeal, the Board finds that the question of appropriate initial ratings for the diabetic complications of peripheral neuropathy are also in appellate status. Notwithstanding that these issues have not previously been separately listed in the Board remand or specifically identified as separate issues at the January 2010 Board hearing, the substance of these issues has been addressed as part of the issue of increased rating for diabetes mellitus. In light of the Board's favorable grant of benefits regarding the ratings assigned for peripheral neuropathy of the lower extremities, it is necessary to set out these issues separately on the title page. In this case the Veteran has alleged that his service- connected disabilities prevent him from obtaining or maintaining all gainful employment for which his education and occupational experience would otherwise qualify him. This claim, however, has already been referred to the RO. Accordingly, an additional remand is not necessary. FINDINGS OF FACT 1. The Veteran's malignant melanoma of the left arm and a lentiginous compound nevus on the chest first manifested many years after service and are unrelated to any incident of service, including exposure to herbicide agents. 2. The Veteran's hypertension is aggravated by his service- connected diabetes mellitus. 3. The Veteran's obstructive sleep apnea is aggravated by his service-connected diabetes mellitus. 4. All the Veteran's symptoms claimed and diagnosed as restless leg syndrome have been rated as a symptom of his service-connected mild diabetic peripheral neuropathy of the lower extremities. 5. Throughout the pendency of the initial rating appeal, the Veteran's diabetes mellitus has been manifested by the need for daily oral hypoglycemic agents and dietary restrictions, but his physical activity has not required regulation. 6. Throughout the pendency of the appeal, the Veteran's nonproliferative diabetic retinopathy of the left eye and bilateral cataracts have not been manifested by impairment of visual acuity or field loss; and he has not been diagnosed with diabetic retinopathy of the right eye. 7. Throughout the pendency of the appeal, the Veteran's erectile dysfunction has been manifested by occasional impotence and decreased sexual desire. His erectile dysfunction is not manifested by total impotence or by penile deformity. 8. For the initial rating appeal period from June 18, 2005, the Veteran's service-connected diabetic peripheral neuropathy of the right lower extremity has been manifested by restless leg syndrome, a burning sensation in the foot, decreased pinprick sensation and decreased vibration sense at the toes, which has been productive of no more than mild incomplete paralysis of the sciatic nerve. 9. For the initial rating appeal period from June 18, 2005, the Veteran's service-connected diabetic peripheral neuropathy of the left lower extremity has been manifested by restless leg syndrome, a burning sensation in the foot, decreased pinprick sensation and decreased vibration sense at the toes, which has been productive of no more than mild incomplete paralysis of the sciatic nerve. CONCLUSIONS OF LAW 1. Malignant melanoma of the left arm and a lentiginous compound nevus on the chest were not incurred in or aggravated by the Veteran's active service, and are not proximately due to or the result of exposure to herbicide agents. 38 U.S.C.A. §§ 1101, 1110, 1112, 1113, 1154, 5103, 5103A, 5107 (West 2002 & Supp. 2009); 38 C.F.R. §§ 3.303, 3.304, 3.307, 3.309, 3.310 (2009). 2. The Veteran's hypertension is aggravated by his service- connected diabetes mellitus. 38 U.S.C.A. §§ 1101, 1110, 1112, 1113, 1154, 5103, 5103A, 5107 (West 2002 & Supp. 2009); 38 C.F.R. §§ 3.303, 3.304, 3.309, 3.310(a) (2009). 3. The Veteran's obstructive sleep apnea is aggravated by his service-connected diabetes mellitus. 38 U.S.C.A. §§ 1101, 1110, 1112, 1113, 1154, 5103, 5103A, 5107 (West 2002 & Supp. 2009); 38 C.F.R. §§ 3.303, 3.304, 3.309, 3.310(a) (2009). 4. The appeal for service connection for restless leg syndrome is without legal merit. 38 U.S.C.A. § 7104 (West 2002 & Supp. 2009); 38 C.F.R. § 4.14 (2009). 5. The criteria for an initial rating higher than 20 percent for diabetes mellitus have not been met. 38 U.S.C.A. §§ 1155, 5103(a), 5103A, 5107 (West 2002 & Supp. 2009); 38 C.F.R. § 4.119, Diagnostic Code (DC) 7913 (2009). 6. The criteria for a separate compensable rating for nonproliferative diabetic retinopathy of the left eye and bilateral cataracts have not been met. 38 U.S.C.A. §§ 1155, 5103(a), 5103A, 5107 (West 2002 & Supp. 2009); 38 C.F.R. § 4.79, DC 6006 (2009). 7. The criteria for a separate compensable disability rating for service-connected erectile dysfunction have not been met. 38 U.S.C.A. §§ 1155, 5103(a), 5103A, 5107 (West 2002 & Supp. 2009); 38 C.F.R. § 4.115b, DC 7522 (2009). 8. The criteria for separate initial rating of 10 percent, but no higher for any period, for peripheral neuropathy of the right lower extremity have been for the period from June 18, 2005. 38 U.S.C.A. §§ 1155, 5103(a), 5103A, 5107 (West 2002 & Supp. 2009); 38 C.F.R. § 4.124a, DCs 8520, 8620, 8621 (2009). 9. The criteria for separate initial rating of 10 percent, but no higher for any period, for peripheral neuropathy of the left lower extremity have been for the period from June 18, 2005. 38 U.S.C.A. §§ 1155, 5103(a), 5103A, 5107 (West 2002 & Supp. 2009); 38 C.F.R. § 4.124a, Diagnostic Codes 8520, 8620, 8621 (2009). REASONS AND BASES FOR FINDINGS AND CONCLUSIONS Duties to Notify and Assist The Veterans Claims Assistance Act of 2000, 38 U.S.C.A. §§ 5100, 5102-5103A, 5106, 5107, 5126 (West 2002 & Supp. 2009), 38 C.F.R. §§ 3.102, 3.156(a), 3.159, 3.326(a) (2009), requires VA to assist a claimant at the time that he or she files a claim for benefits. As part of this assistance, VA is required to notify claimants of what they must do to substantiate their claims. 38 U.S.C.A. § 5103(a); 38 C.F.R. § 3.159(b)(1). The notice required by the VCAA can be divided into three elements. Specifically, VA must inform the claimant of any information and evidence not of record (1) that is necessary to substantiate the claim; (2) that the claimant is to provide; and (3) that VA will attempt to obtain. Beverly v. Nicholson, 19 Vet. App. 394, 403 (2005) (outlining VCAA notice requirements). With respect to the claims for service connection for the residuals of the removal of skin lesions and restless leg syndrome, notice was provided to the Veteran in October and December 2003, prior to the initial adjudication of his claims in February 2004. The content of the notice letter fully complies with the requirements of 38 U.S.C.A. § 5103(a) and 38 C.F.R. § 3.159(b) regarding VA's duty to notify. The Veteran was not provided with the Dingess elements of VCAA notice. However, given the denial of the claims, any questions as to a disability rating or effective date are moot regarding these issues. The Veteran has not been prejudiced by VA's failure to provide notice earlier on these elements of his claims. Furthermore, the Veteran was told it was his responsibility to support the claims with appropriate evidence, and he was provided with the text of the relevant regulations relating to VA's duty to notice and assist. With respect to VA's duty to assist, the RO attempted to obtain all medical records identified by the Veteran. The Veteran's service treatment records are in the claims file. VA and private treatment records are in the claims folder. VA is only required to make reasonable efforts to obtain relevant records that the Veteran has adequately identified. 38 U.S.C.A. § 5103A(b)(1) (West 2002). He has not identified any other treatment records aside from those that are already of record. Thus, VA has made every reasonable effort to obtain all records relevant to the Veteran's claims. Under the VCAA, VA is obliged to provide an examination when the record contains competent evidence that the claimant has a current disability or signs and symptoms of a current disability, the record indicates that the disability or signs and symptoms of disability may be associated with active service; and the record does not contain sufficient information to make a decision on the claim. 38 U.S.C.A. § 5103A(d) (West 2002); McLendon, 20 Vet. App. 79. The types of evidence that 'indicate' that a current disability 'may be associated' with military service include, but are not limited to, medical evidence that suggests a nexus but is too equivocal or lacking in specificity to support a decision on the merits, or credible evidence of continuity of symptomatology such as pain or other symptoms capable of lay observation. McLendon at 83. The threshold for finding a link between current disability and service is low. Locklear v. Nicholson, 20 Vet. App. 410 (2006). The Veteran was not provided with an examination with respect to his claim for service connection for the residuals of the removal of his skin lesions. However, his service treatment records do not show complaints of or treatment for skin problems. Additionally, he has not been diagnosed with a skin disorder that has been shown to have a positive association with exposure to herbicide agents. As there is no evidence of a skin disorder in service, and there is no probative evidence that his skin lesions may be associated with his active service, including as a result of exposure to herbicide agents, the facts of this case do not meet the criteria to warrant a VA examination. See McLendon; see also 38 U.S.C.A. § 5103A(d)(2); 38 C.F.R. § 3.159(c)(4)(i) (2009). The Veteran also was not provided with an examination with respect to his claim of service connection for his restless leg syndrome. However, given that the Board has determined that the Veteran's restless leg syndrome is a manifestation of his service-connected diabetic peripheral neuropathy, and is therefore denying the claim for service connection as moot, the Board finds that, because the Veteran was afforded a VA examination for his diabetic neuropathy, the failure to provide an examination related to the service connection claim was not prejudicial. With respect to the claims for service connection for hypertension and sleep apnea, secondary to service-connected diabetes mellitus, further assistance or notice is not required under the VCAA. The Board is fully granting the claims and they are substantiated. The Veteran's claim for a higher initial rating than 20 percent for diabetes mellitus arises from his disagreement with the initial rating assigned following the grant of service connection. Once a claim is granted it is substantiated and additional notice is not required. Thus, any defect in the notice with respect to this claim is not prejudicial. Hartman v. Nicholson, 483 F.3d 1311 (Fed. Cir. 2007). As to VA's duty to assist the Veteran with his claim for a higher initial rating, the Board notes that pertinent records from all relevant sources identified by him, and for which he authorized VA to request, have been associated with the claims folder. In addition, the Veteran has been afforded multiple examinations with respect to this claim. 38 U.S.C.A. § 5103A. The associated reports of examination are thorough, and are consistent with the clinical evidence of record. As such, the Board finds that there is no further action to be undertaken to comply with the provisions of 38 U.S.C.A. § 5103(a), § 5103A (West 2002 & Supp. 2009), or 38 C.F.R. § 3.159 (2009). Service Connection Laws and Regulations Service connection may be granted for a disability resulting from disease or injury incurred in or aggravated by active military service. 38 U.S.C.A. § 1110, 1131 (West 2002); 38 C.F.R. § 3.303. Service connection generally requires evidence of a current disability with a relationship or connection to an injury or disease or some other manifestation of the disability during service. Boyer v. West, 210 F.3d 1351 (Fed. Cir. 2000); Degmetich v. Brown, 104 F. 3d 1328 (1997); Cuevas v. Principi, 3 Vet. App. 542 (1992); Rabideau v. Derwinski, 2 Vet. App. 141 (1992). Service connection for certain chronic diseases, including malignant tumors and cardiovascular-renal disease, such as hypertension, will be rebuttably presumed if they are manifest to a compensable degree within one year following active service. 38 U.S.C.A. §§ 1101, 1112, 1113, 1137 (West 2002); 38 C.F.R. §§ 3.307, 3.309 (2009). The Veteran's obstructive sleep apnea is not a disorder for which service connection may be granted on a presumptive basis. Service connection may be granted for any disease diagnosed after discharge, when all the evidence, including that pertinent to service, establishes that the disease was incurred in service. Presumptive periods are not intended to limit service connection to diseases so diagnosed when the evidence warrants direct service connection. The presumptive provisions of the statute and VA regulations implementing them are intended as liberalizations applicable when the evidence would not warrant service connection without their aid. 38 C.F.R. § 3.303(d). For the showing of chronic disease in service, there must be a combination of manifestations sufficient to identify the disease entity and sufficient observation to establish chronicity at the time. If chronicity in service is not established, evidence of continuity of symptoms after discharge is required to support the claim. 38 C.F.R. § 3.303(b) (2009). A disability which is proximately due to or the result of a service-connected disease or injury shall be service- connected. 38 C.F.R. § 3.310 (2009). Under 38 C.F.R. § 3.310, secondary service connection is permitted based on aggravation; compensation is payable for the degree of aggravation of a non-service-connected disability caused by a service-connected disability. Allen v. Brown, 7 Vet. App. 439 (1995) (en banc). "A determination of service connection requires a finding of the existence of a current disability and a determination of a relationship between the disability and an injury or disease incurred in service." Watson v. Brown, 4 Vet. App. 309, 314 (1993). Establishing service connection on a secondary basis essentially requires evidence sufficient to show: (1) that a current disability exists; and (2) that the current disability was either caused or aggravated by a service-connected disability. 38 C.F.R. § 3.303, 3.310. In relevant part, 38 U.S.C.A. 1154(a) (West 2002) requires that VA give "due consideration" to "all pertinent medical and lay evidence" in evaluating a claim for disability or death benefits. Davidson v. Shinseki, 581 F.3d 1313 (Fed. Cir. 2009). "Lay evidence can be competent and sufficient to establish a diagnosis of a condition when (1) a layperson is competent to identify the medical condition, (2) the layperson is reporting a contemporaneous medical diagnosis, or (3) lay testimony describing symptoms at the time supports a later diagnosis by a medical professional." Jandreau v. Nicholson, 492 F.3d 1372, 1377 (Fed. Cir. 2007); see also Buchanan v. Nicholson, 451 F.3d 1331, 1337 (Fed. Cir. 2006) ("the Board cannot determine that lay evidence lacks credibility merely because it is unaccompanied by contemporaneous medical evidence"). Service Connection for Malignant Melanoma and Nevus The Veteran contends that he developed a malignant melanoma on his left arm and a lentiginous compound nevus on his chest as a result of exposure to herbicide agents in service. A veteran who, during active service, served in the Republic of Vietnam during the period beginning on January 9, 1962, and ending on May 7, 1975, shall be presumed to have been exposed to an herbicide agent, unless there is affirmative evidence to establish that the veteran was not exposed to any such agent during that service. 38 C.F.R. § 3.307(a)(6)(iii). The Veteran in this case served on active duty in Vietnam during the applicable time period. Thus, the Veteran in this case will be afforded the presumption of exposure to Agent Orange. However, the Veteran has not been diagnosed with a skin disorder that has been shown to have a positive association with exposure to herbicides. Thus, in the absence of any medical evidence relating his skin lesions to exposure to herbicide agents, service connection as secondary to exposure to herbicide agents is not warranted. Stefl v. Nicholson, 21 Vet. App. 120 (2007). In this case, there is no such medical evidence linking the Veteran's skin lesions to exposure to herbicide agents. Accordingly, service connection for the residuals of the removal of the skin lesions as secondary to exposure to herbicide agents is not warranted. The Board thus turns to the merits of the Veteran's claim on alternate bases. The Veteran's service treatment records are negative for any complaints, findings, or diagnosis of any skin disorders. The Board thus finds that chronicity in service is not established in this case. 38 C.F.R. § 3.303(b). As chronicity in service has not been established, a showing of continuity of symptoms after discharge is required to support the Veteran's claim for service connection of the residuals of the removal of his skin lesions. 38 C.F.R. § 3.303(b). The Veteran asserts that his skin lesions were present for many years before he sought treatment. He does not, however, contend that they were present either in service or shortly after his separation from service. The first post-service clinical evidence of treatment for skin problems is dated in September 1998. The Veteran was referred by his primary care physician for evaluation of a changing lesion on his left arm. The Veteran stated that the reddish dark spot on his left arm had been present for many years. He initially had thought that the lesion was a blood blister. The lesion occasionally swelled, and recently, he had noticed that it had increased in size and had changed colors. He denied a past history of skin cancer or melanoma. Physical examination revealed a 7 X 8 mm, asymmetrical, irregularly pigmented lesion on the lateral aspect of the left upper arm. The lesion was characterized by various irregular aggregates of a darker pigment and a raised, erythematous zone at the periphery. There were no hypopigmented areas noted. The skin examination was otherwise normal. The lesion was excised. Biopsy confirmed malignant melanoma. A chest X-ray and blood work were normal. On follow up evaluation in October 1998, the Veteran stated that the scar had healed well, although he continued to experience occasional numbness in the area of the excision. He otherwise had no complaints. Physical examination revealed a well-healed scar in the area of the excision. There was no evidence of a recurrence of the lesion in that area. Skin examination otherwise revealed a very dark, asymmetrical 4 X 7 mm hyperpigmented macule. The assessment of the skin lesion on the chest was dysplastic nevus versus atypical junctional nevus. Given the Veteran's history of melanoma, it was recommended that the lesion be excised. In February 1999, the skin lesion on the Veteran's chest was excised. Biopsy resulted in a diagnosis of lentiginous compound nevus. Subsequent clinical records dated to December 2009 show that the Veteran had a history of malignant melanoma, without recurrence. He has not had any additional skin lesions removed since February 1999. At no time did any treatment provider relate his skin lesions to his period of active service, including exposure to herbicide agents. Service connection may be granted when all the evidence establishes a medical nexus between military service and current complaints. Degmetich v. Brown, 104 F. 3d 1328, 1332 (1997); Rabideau v. Derwinski, 2 Vet. App. 141, 143 (1992). In this case, there is no probative evidence establishing a medical nexus between military service and the Veteran's skin lesions. Thus, service connection for the residuals of the removal of the lesions is not warranted. While the Veteran is competent to testify that his skin lesions were present for many years before he sought treatment for the lesions, he is not competent to diagnose the lesions as related to exposure to herbicide agents. Jandreau v. Nicholson, 492 F.3d 1372 (Fed. Cir. 2007) (lay evidence can be competent and sufficient to establish a diagnosis of a condition when a layperson is competent to identify the medical condition, or reporting a contemporaneous medical diagnosis, or the lay testimony describing symptoms at the time supports a later diagnosis by a medical professional); Buchanan v. Nicholson, 451 F.3d. 1331 (Fed. Cir. 2006) (lay evidence is one type of evidence that must be considered and competent lay evidence can be sufficient in and of itself). Similarly, the Veteran is not competent to provide either a diagnosis or the medical nexus, and a medical professional has not related his skin lesions to his active service, including his presumed exposure to herbicide agents. Thus, the Veteran's lay assertions are not competent or sufficient. Jandreau, 492 F.3d 1372. In sum, the weight of the evidence shows that the Veteran's malignant melanoma of the left arm and lentiginous compound nevus on the chest first manifested many years after his period of active service and is not related to service or to any incident therein. As the preponderance of the evidence is against the claim for service connection for the residuals of the removal of malignant melanoma from the left arm, and a lentiginous compound nevus from the chest, the claim must be denied. 38 U.S.C.A. § 5107(b); 38 C.F.R. § 3.102; Gilbert v. Derwinski, 1 Vet. App. 49 (1990). Service Connection for Hypertension The Veteran contends that, although he was diagnosed with hypertension many years before he was diagnosed with diabetes mellitus, he is entitled to service connection for hypertension because his hypertension, at the very least, has been aggravated by his diabetes mellitus. The Veteran's service treatment records are negative for any diagnosis or treatment of hypertension. On examination prior to service separation, no cardiovascular abnormality, including hypertension, was found. As the Veteran did not receive any treatment for any cardiovascular complaints, and no abnormality was noted on separation, the Board finds that the weight of the evidence establishes no chronicity of symptomatology of hypertension in this case. 38 C.F.R. § 3.303 (2009). As chronicity in service has not been established, a showing of continuity of symptoms after discharge is required to support the Veteran's claim for service connection of his hypertension. 38 C.F.R. § 3.303(b). The Veteran was reportedly diagnosed with hypertension a few years after his separation from service. The record of his initial diagnosis is not of record. Clinical records dated in March 1982, however, show that the Veteran reported a history of hypertension for which he had been prescribed medication. Subsequent records dated to December 2009 show continued treatment for hypertension, which was generally felt to be under poor control. The Veteran was initially diagnosed with diabetes mellitus in January 2002. Records dated prior to January 2002, however, show that the Veteran was felt to have metabolic syndrome prior to being formally diagnosed with diabetes mellitus in January 2002. On VA examination in December 2003, the Veteran reported that he had been hypertensive for the past 25 years. He stated that at the present time, neither the medication prescribed for his hypertension, nor the hypertension itself, caused him any problems. His blood pressure was read three times, with the following results: 175/107 mmHg, 161/100 mmHg, and 168/102 mmHg. The diagnosis was essential hypertension, well-controlled and not related to his diabetes. The examiner noted that while the triad of diabetes mellitus, obesity, and hypertension were all closely interrelated, and affected one another, the Veteran had had hypertension for 25 years. A February 2005 statement from the Veteran's private physician shows that the Veteran's hypertension was felt to be related to his diabetes mellitus. The Veteran next underwent VA examination in June 2005. At that time, the Veteran reported a 30-year history of hypertension. His blood pressure at the time of the examination measured 164/86 mmHg. The examiner did not offer an opinion as to whether the Veteran's hypertension was in any way related to his diabetes mellitus. The Veteran again underwent VA examination in June 2007. The Veteran at that time stated that he had been diagnosed with hypertension in 1972 or 1973, and that he had been on medication for treatment of hypertension ever since. He described no problems or symptoms related to his high blood pressure. His blood pressure was read three times, with the following results: 139/82 mmHg, 111/74 mmHg, and 111/75 mmHg. The diagnosis was essential hypertension. The examiner noted that the Veteran met the criteria for metabolic syndrome, and that metabolic syndrome was manifested, among other things, by hypertension. Because the Veteran met the criteria for metabolic syndrome before he was diagnosed with diabetes mellitus, the examiner opined that it was at least as likely as not that his diabetes mellitus had increased the severity of his hypertension. The examiner was unable to precisely state the degree to which the hypertension had been aggravated, due to difficulty in establishing a baseline. The Veteran underwent VA examination for a final time in May 2008. His blood pressure was read three times, with the following results: 133/93 mmHg, 140/90 mmHg, and 130/80 mmHg. The examiner opined that although hypertension was diagnosed many years prior to the diagnosis of diabetes mellitus, a review of the medical records indicated that the Veteran had had increased difficulty with blood pressure control in the years just prior to his formal diagnosis of diabetes mellitus, and since that time, had required several upward adjustments in antihypertensive medications. Thus, it appeared that the hypertension had been aggravated as a result of the diabetes mellitus. The examiner additionally noted that the metabolic abnormalities that precede the diagnosis of overt diabetes mellitus will cause hypertension through a variety of mechanisms and that these mechanisms will persist through the course of the disease. The examiner then stated that it was not possible, without resorting to speculation, to apportion the cause of the hypertension to diabetes versus any other etiology. Here, the first post-service clinical evidence related to the Veteran's hypertension is dated in March 1982, 10 years after his separation from service. He is accordingly not entitled to service connection on a presumptive basis. However, the Veteran does not contend that his hypertension is a result of his active service, but rather that it is related to his service-connected diabetes mellitus. Specifically, he contends that his diabetes mellitus has aggravated his hypertension. A causal link is not required for service connection on a secondary basis. A showing that the service-connected disability aggravates the condition at issue will also satisfy the requirements for service connection on a secondary basis. Allen v. Brown, 7 Vet. App. 439 (1995). In such cases, however, only the portion attributable to the service-connected condition will qualify for compensation. In this case, both the June 2007 and May 2008 examiners determined that it was as likely as not that the Veteran's hypertension was aggravated by his service-connected diabetes mellitus. Both examiners provided detailed rationales for these opinions, indicating that metabolic syndrome that existed prior to the formal diagnosis of diabetes mellitus had increased the severity of the hypertension, as supported by clinical records showing that the dosage of the medication prescribed for hypertension had to be increased on numerous occasions in the years immediately preceding and after the diagnosis of diabetes mellitus. In considering these opinions, along with the other opinions of record, the Board finds it at least as likely as not that the Veteran's hypertension is aggravated by his service- connected diabetes mellitus. As such, the Board concludes that the Veteran's claim for entitlement to service connection for hypertension, as secondary to his service- connected diabetes mellitus, is warranted. Hanson v. Derwinski, 1 Vet. App. 512 (1991). Service Connection for Obstructive Sleep Apnea The Veteran contends that, although he was diagnosed with obstructive sleep apnea many years before he was diagnosed with diabetes mellitus, he is entitled to service connection for obstructive sleep apnea because his obstructive sleep apnea, at the very least, has been aggravated by his diabetes mellitus. The Veteran's service treatment records are negative for any diagnosis or treatment of obstructive sleep apnea. On examination prior to service separation, the Veteran did not complain of symptoms consistent with obstructive sleep apnea, and no such diagnosis was made. As the Veteran did not receive any treatment for any obstructive sleep apnea in service, and no abnormality was noted on separation, the Board finds that the weight of the evidence does not establish chronicity of symptoms in service in this case. 38 C.F.R. § 3.303. As chronicity in service has not been established, a showing of continuity of symptoms after discharge is required to support the Veteran's claim for service connection of his obstructive sleep apnea. 38 C.F.R. § 3.303(b). The record reflects that the Veteran was referred for an initial sleep evaluation in March 1996. He reported a history of snoring loudly in all positions, and stated that he had been observed to have apneas lasting 15 seconds or longer. He experienced some daytime tiredness but was not actually falling asleep unintended. He stated that he went to bed around 10:00 p.m. and got up at 5:45 a.m. He reportedly had no problems first getting up in the morning. The Veteran's past medical history was significant for a history of hypertension and being overweight. Sleep apnea was felt to be quite likely. A May 1996 sleep study revealed very severe obstructive sleep apnea, causing serious oxygen desaturations, cardiac dysrhythmias, and severely disturbed sleep. Treatment with a CPAP machine was determined to be of absolute medical necessity due to the serious health risks associated with the severity of his obstructive sleep apnea. Subsequent records show continued assessments of and treatment for obstructive sleep apnea. The Veteran underwent VA examination for obstructive sleep apnea, as possibly secondary to diabetes mellitus, in June 2007. At the time of the examination, the Veteran stated that he had been using a CPAP machine since he was initially diagnosed with sleep apnea, approximately 15 years ago. His current symptoms included some daytime somnolence and fatigue, but improved as compared to how he had felt prior to beginning to use the CPAP machine. The examiner reviewed the Veteran's claims file and other medical texts concerning the relationship between sleep apnea and diabetes mellitus. The examiner noted that the risk factors for developing sleep apnea included obesity and/or certain upper airway abnormalities. Rare causes of sleep apnea included hypothyroidism, acromegaly, and amyloidosis. Diabetes mellitus was not listed as a cause. However, the Veteran met the criteria for a diagnosis of metabolic syndrome associated with diabetes mellitus, which was known to contribute to obesity. The Veteran had developed sleep apnea long before he was diagnosed with diabetes mellitus. Because there were so many factors causing and effecting obesity, the examiner opined that he was unable to resolve without resorting to speculation whether the Veteran had any worsening of sleep apnea as a result of his diabetes mellitus. In a June 2007 statement, the Veteran's private physician related his obstructive sleep apnea to his diabetes mellitus. Specifically, the physician stated that it was at least as likely as not that the Veteran's current sleep apnea was proximately due to or the result of, or had been increased in severity as a result of his diabetes mellitus. The physician reasoned that the diabetes mellitus had contributed to weight gain, which had contributed to the obstructive sleep apnea. As noted above, a causal link is not required for service connection on a secondary basis. A showing that the service- connected disability aggravates the condition at issue will also satisfy the requirements for service connection on a secondary basis. Allen, 7 Vet. App. 439. In such cases, however, only the portion attributable to the service- connected condition will qualify for compensation. In this case, the June 2007 VA examiner essentially opined that the Veteran's obstructive sleep apnea could be related to his diabetes mellitus, as a result of weight gain associated with diabetes mellitus, but that because there were so many factors influencing the development of obesity, a definitive relationship could not be made without resort to speculation. This tentative opinion, together with the more definitive private opinion relating the sleep apnea to weight gain associated with diabetes mellitus, tends to support the Veteran's claim of aggravation. Significantly, there is no probative evidence to the contrary. Resolving all doubt in favor of the Veteran, as is required by law, the Board finds that the Veteran's obstructive sleep apnea is aggravated by his service-connected diabetes mellitus. As such, the Board concludes that the Veteran's claim for entitlement to service connection for obstructive sleep apnea, as secondary to his service-connected diabetes mellitus, is warranted. Hanson v. Derwinski, 1 Vet. App. 512 (1991). Service Connection for Restless Leg Syndrome The Veteran contends that he is entitled to service connection for restless leg syndrome, secondary to his service-connected diabetes mellitus. He does not contend that he first developed restless leg syndrome in service, but that he later developed leg syndrome as a result of his service-related diabetes mellitus. The Veteran's service treatment records are negative for any evidence of restless leg syndrome. As there is no evidence of restless leg syndrome in service, the Board finds that restless leg syndrome did not manifest during service. 38 C.F.R. § 3.303(b). As chronicity in service has not been established, a showing of continuity of symptoms after discharge is required to support the Veteran's claim for service connection of his skin ulcer. 38 C.F.R. § 3.303(b). The first record of any complaint regarding restless leg syndrome is dated in March 1996. A May 1996 sleep study revealed moderately severe restless legs and periodic limb movements. A March 1999 study confirmed his diagnosis of moderately severe restless legs and periodic limb movements. Subsequent records show continued complaints of and treatment for restless leg syndrome. A June 2007 statement from the Veteran's private physician indicated that his restless leg syndrome was felt to be a probable component of mild diabetic neuropathy. At no time did any treating clinician otherwise relate the restless leg syndrome to any other aspect of the Veteran's active service. To the extent that the Veteran's restless leg syndrome has been determined to be a component of his diabetic peripheral neuropathy (each lower extremity is rated 10 percent disabling), and therefore related to his service-connected diabetes mellitus, because the Veteran is already service- connected for diabetic peripheral neuropathy, service connection for restless leg syndrome secondary to diabetes mellitus, including diabetic peripheral neuropathy, is rendered moot. The Veteran's restless leg syndrome is a manifestation of the already service-connected diabetic peripheral neuropathy, rather than a separate and distinct secondary disability. To grant service connection and rate restless leg syndrome as a separate disability would violate the rule against pyramiding. See 38 C.F.R. § 4.14 (the evaluation of the same manifestation under different diagnoses are to be avoided). For this reason, the Veteran is not eligible for service connection for restless leg syndrome on a secondary basis. There is no probative evidence otherwise demonstrating that the Veteran's restless leg syndrome is related to his active service. Accordingly, service connection on a direct basis is not warranted. Even if there was such evidence, however, because the symptoms related to his restless leg syndrome are considered in determining the appropriate disability rating for his diabetic peripheral neuropathy, a separate compensable rating for restless leg syndrome would amount to impermissible pyramiding. 38 C.F.R. § 4.14. In sum, the Board has carefully weighed the evidence of record, the statements of the Veteran, and the treatment records, in light of the applicable law, and finds that the claim for service connection for restless leg syndrome must be denied as moot, given that the restless leg syndrome has been determined to be a manifestation of the Veteran's already service-connected diabetic peripheral neuropathy of the lower extremities. Rating Criteria Ratings for service-connected disabilities are determined by comparing the veteran's symptoms with criteria listed in VA's Schedule for Rating Disabilities, which is based, as far as practically can be determined, on average impairment in earning capacity. Separate diagnostic codes identify the various disabilities. 38 C.F.R. Part 4 (2009). When rating a service-connected disability, the entire history must be borne in mind. Schafrath v. Derwinski, 1 Vet. App. 589 (1991). Where there is a question as to which of two ratings shall be applied, the higher rating will be assigned if the disability picture more nearly approximates the criteria required for that rating. Otherwise, the lower rating will be assigned. 38 C.F.R. § 4.7 (2009). In view of the number of atypical instances it is not expected, especially with the more fully described grades of disabilities, that all cases will show all the findings specified. Findings sufficiently characteristic to identify the disease and the disability therefrom, and above all, coordination of rating with impairment of function will, however, be expected in all instances. 38 C.F.R. § 4.21 (2009). The Board will consider entitlement to staged ratings to compensate for times since filing the claim when the disability may have been more severe than at other times during the course of the claim on appeal. Fenderson v. West, 12 Vet. App. 119 (1999); Hart v. Mansfield, 21 Vet. App. 505 (2009). Pursuant to § 3.321(b)(1), the Under Secretary for Benefits or the Director, Compensation and Pension Service, is authorized to approve an extraschedular evaluation if the case "presents such an exceptional or unusual disability picture with such related factors as marked interference with employment or frequent periods of hospitalization as to render impractical the application of the regular schedular standards." 38 C.F.R. § 3.321(b)(1) (2009). The question of an extraschedular rating is a component of a claim for an increased rating. See Bagwell v. Brown, 9 Vet. App. 337, 339 (1996). Although the Board may not assign an extraschedular rating in the first instance, it must specifically adjudicate whether to refer a case for extraschedular evaluation when the issue either is raised by the claimant or is reasonably raised by the evidence of record. Barringer v. Peake, 22 Vet. App. 242 (2008). If the evidence raises the question of entitlement to an extraschedular rating, the threshold factor for extraschedular consideration is a finding that the evidence before VA presents such an exceptional disability picture that the available schedular evaluations for that service- connected disability are inadequate. Therefore, initially, there must be a comparison between the level of severity and symptomatology of the claimant's service-connected disability with the established criteria found in the rating schedule for that disability. Thun v. Peake, 22 Vet. App. 111 (2008). Under the approach prescribed by VA, if the criteria reasonably describe the claimant's disability level and symptomatology, then the claimant's disability picture is contemplated by the rating schedule, the assigned schedular evaluation is, therefore, adequate, and no referral is required. In the second step of the inquiry, however, if the schedular evaluation does not contemplate the claimant's level of disability and symptomatology and is found inadequate, the RO or Board must determine whether the claimant's exceptional disability picture exhibits other related factors such as those provided by the regulation as "governing norms." 38 C.F.R. 3.321(b)(1) (related factors include "marked interference with employment" and "frequent periods of hospitalization"). Initial Rating for Diabetes Mellitus The Veteran's diabetes mellitus was initially rated 20 percent disabling under Diagnostic Code 7913 from September 2003. The 20 percent initial disability rating for diabetes mellitus was based on evidence showing oral hypoglycemic agents and a restricted diet were required. The Veteran's diabetic complications have been separately rated. These include a 0 percent rating for erectile dysfunction assigned under Diagnostic Code 7522 (from September 2003). During the appeal of the initial rating for diabetes mellitus, 0 percent ratings were assigned under Diagnostic Code 8520 for peripheral neuropathy of the right and left lower extremities prior to May 2, 2008, and as 10 percent disabling for the period since May 2, 2008. A 0 percent rating under Diagnostic Code 6099-6006 was also assigned for nonproliferative diabetic retinopathy of the left eye and bilateral cataracts (from February 2004). Diagnostic Code 7913 provides for a 20 percent rating where the diabetes mellitus requires insulin and a restricted diet, or an oral hypoglycemic agent and a restricted diet. A 40 percent rating is warranted for diabetes mellitus requiring insulin, restricted diet, and regulation of activities. A 60 percent rating is warranted for diabetes mellitus requiring insulin, restricted diet, and regulation of activities with episodes of ketoacidosis or hypoglycemic reactions requiring one or two hospitalizations per year or twice a month visits to a diabetic care provider, plus complications that would not be compensable if separately evaluated. A 100 percent rating is warranted for diabetes mellitus requiring more than one daily injection of insulin, restricted diet, and regulation of activities (avoidance of strenuous occupational and recreational activities) with episodes of ketoacidosis or hypoglycemic reactions requiring at least three hospitalizations per year or weekly visits to a diabetic care provider, plus either progressive loss of weight and strength or complications that would be compensable if separately evaluated. 38 C.F.R. § 4.119, Diagnostic Code 7913. Complications of diabetes are evaluated separately unless they are part of the criteria used to support a 100 percent rating. Noncompensable complications are deemed part of the diabetic process under Diagnostic Code 7913. 38 C.F.R. § 4.119, Diagnostic Code 7913, Note (1) (2009). The Veteran was diagnosed with diabetes mellitus in January 2002. Since that time, he has been advised to follow a restricted diet for control of his diabetes mellitus. This diet consists of restricted calories and a low fat regimen. According to VA and private examiners, the Veteran's diabetes mellitus is under good control. The Veteran has also been prescribed oral hypoglycemic agents to control his diabetes mellitus since the initial diagnosis. His dosages have increased periodically since the initial prescription. He has not been prescribed insulin injections as a part of his control regimen. In addressing the third criterion for a higher rating of 40 percent under Diagnostic Code 7913, there is no evidence in this case that the Veteran has been prescribed or advised to avoid strenuous occupational and recreational activities. See 61 Fed. Reg. 20,440, 20,446 (May 7, 1996) (defining "regulation of activities," as used by VA in Diagnostic Code 7913). Clinical records dated from January 2002 to December 2009 show that the Veteran consistently has been advised to exercise in order to both mediate his weight and control his diabetes. These records also show that the Veteran has been able to lose a considerable amount of weight as a result of exercise. He continues, however, to struggle with his weight. On VA examination in December 2003, the Veteran stated that his activities were not restricted by his diabetes mellitus. On VA examination in June 2005, the Veteran noted that he had gained approximately 60 pounds over the last three years. He stated that his diabetes mellitus affected him in that he felt more fatigued than he had previously. On VA examination in May 2008, the examiner noted that the Veteran was not restricted in his ability to perform strenuous activities. Lastly, in January 2010 testimony before the Board, the Veteran acknowledged that he had been advised by his physicians to exercise, without restriction. In order to meet the criteria for a higher rating of 40 percent, the Veteran must have been told that he should avoid any strenuous occupational or recreational activities. See 38 C.F.R. § 4.119, Diagnostic Code 7913 (emphasis added). The available evidence does not indicate that the Veteran has been prescribed or advised to avoid strenuous occupational and recreational activities, as is required in order to merit a higher rating of 40 percent. The fact that the Veteran has been advised that he should exercise, in the absence of specified medical guidelines for that exercise, does not meet the criterion requiring regulation of activity so as to warrant a 40 percent evaluation under Diagnostic Code 7913. While the Veteran has been prescribed a restricted diet and oral hypoglycemic agents in effort to control his diabetes, he has not been prescribed insulin or limited physical activity or advised to avoid recreational activities. The Veteran therefore does not meet the criteria for a higher rating of 40 percent for any period of initial rating appeal. 38 C.F.R. § 4.119, Diagnostic Code 7913. As the preponderance of the evidence is against the claim for a higher initial rating than 20 percent for diabetes mellitus, the "benefit-of-the-doubt" rule does not apply, and the claim must be denied. Rating Noncompensable Diabetic Complications Because the Veteran has generally disagreed with the initial rating for diabetes mellitus, his disagreement is broad enough to include the question of ratings for diabetic complications. The Board has considered whether the Veteran's diabetic complications warrant higher ratings. Retinopathy Turning to the Veteran's nonproliferative diabetic retinopathy of the left eye and bilateral cataracts, the Board notes that the Rating Schedule does not contain a specific diagnostic code for diabetic retinopathy. However, where an unlisted condition is encountered it is permissible to rate it under a closely related disease or injury, in which not only the functions affected, but the anatomical localization and symptomatology are closely analogous. See 38 C.F.R. § 4.20 (2009). In this case, the Board finds that 38 C.F.R. § 4.84, DC 6006, which pertains to retinitis, is the most closely analogous diagnostic code. Under the provisions of DCs 6000 through 6009, diseases of the eye, in chronic form, are to be rated from 10 percent to 100 percent disabling for impairment of visual acuity or loss of field of vision, pain, rest- requirements, or episodic incapacity, combining an additional rating of 10 percent during continuance of active pathology. A minimum rating of 10 percent is to be assigned during active pathology. 38 C.F.R. § 4.84, Diagnostic Codes 6000 - 6009. On review of the determinative findings of record, the evidence does not support the assignment of a compensable rating for diabetic retinopathy of the left eye with bilateral cataracts. VA treatment records show that the Veteran was initially diagnosed with "very mild" nonproliferative diabetic retinopathy of the left eye and bilateral cataracts in February 2004. There was no impairment of visual acuity attributable to the diagnoses, or of field loss. On each subsequent eye examination, the Veteran's visual acuity was shown to be correctable to 20/20, and no worse than 20/30, uncorrected, bilaterally. More significantly, no subsequent eye examination revealed nonproliferative diabetic retinopathy or cataracts of either eye. While the Veteran was noted to have correctable refractive error, he was consistently noted to have "well controlled diabetes mellitus without retinopathy, bilaterally." On VA examination in June 2005, the Veteran stated that he had recently undergone a diabetic eye examination and had been informed that "everything was normal." Retinopathy was not diagnosed at the time of the VA examination. On VA examination in May 2008, the Veteran's visual acuity was determined to be normal. No cataracts were found to be present. Retinopathy was not diagnosed. Based on the evidence above, i.e. corrected visual acuity of 20/20, bilaterally, and uncorrected visual acuity of 20/30 bilaterally, with no visual field loss, the Veteran is not entitled to a compensable rating under 38 C.F.R. § 4.84, Table V, Ratings for Central Visual Acuity Impairment. Accordingly, the evidence does not support a separate compensable rating based on decreased visual acuity. Erectile Dysfunction On the question of whether a compensable rating is warranted for the diabetic complication of erectile dysfunction, the Veteran's erectile dysfunction is rated noncompensably disabling under Diagnostic Code 7522, which pertains to deformity of the penis with loss of erectile power. While the Veteran has not specifically been diagnosed with that disability, it is permissible to rate a diagnosed condition that does not match any of the diagnostic codes contained in the rating schedule under a closely related disease or injury, in which not only the functions affected, but the anatomical localization and symptomatology are closely analogous. Conjectural analogies will be avoided, as will the use of analogous ratings for conditions of doubtful diagnosis, or for those not fully supported by clinical and laboratory findings. 38 C.F.R. § 4.20 (2009). The RO rated his erectile dysfunction, by analogy, under DC 7522. While no diagnostic code specifically addresses the diagnosis of erectile dysfunction, DC 7522 does address loss of erectile power, which is precisely the symptomatology described by the Veteran. Moreover, that is the only diagnostic code that specifically addresses erectile function. The Board can identify no more appropriate diagnostic code and the veteran has not identified one. Butts v. Brown, 5 Vet. App. 532 (1993). Accordingly, the Board will proceed with an analysis of the Veteran's disability under this diagnostic code. Diagnostic Code 7522 provides for a single 20 percent rating where the evidence shows deformity of the penis with loss of erectile power. 38 C.F.R. § 4.115(b), DC 7522. The provisions of 38 C.F.R. § 4.31 indicate that where the criteria for a compensable rating under a diagnostic code are not met, and the schedule does not provide for a zero percent evaluation, a zero percent evaluation will be assigned when the required symptomatology is not shown. 38 C.F.R. § 4.31 (2009). Therefore, where both loss of erectile power and deformity are not demonstrated, a 0 percent rating will be assigned. The Veteran initially complained of erectile dysfunction in February 2000. He was prescribed a trial of Viagra. Records dated in November 2000 show that he reported improvement in erectile dysfunction. Subsequent records dated to December 2009 show that the Veteran continued to complain of difficulty with erectile dysfunction, for which a variety of different medications were tried. On VA examination in June 2005, the Veteran stated that he was using Viagra for erectile dysfunction, and that the Viagra helped. He was diagnosed with impotence secondary to diabetes mellitus. Physical examination, however, was not conducted. On VA examination in May 2008, the Veteran stated that he had erectile dysfunction for which he took oral medication. He estimated that the medication enabled vaginal penetration more than half of the time. He was diagnosed with erectile dysfunction secondary to diabetes mellitus. Physical examination, however, was not conducted. The Veteran underwent VA genitourinary examination in September 2009. At the time of the examination, the Veteran stated that the medication he was currently taking for his erectile dysfunction was not effective. He reported that he had taken some of the medication two weeks prior to the examination and that he had been unable to have intercourse. He described experiencing "bending" of the penis when attempting intercourse. His erectile dysfunction had reportedly gotten worse over the years. Physical examination in September 2009 revealed retraction of the penis, with the shaft not visible; only the most distal part was visible. The examiner noted that the Veteran might have Peyronie's disease, which resulted in deviation of the erect penis, but also noted that there were no records to substantiate such diagnosis. The cause of Peyronie's disease, however, was unknown. In this case, the Veteran has been diagnosed with loss of erectile power (erectile dysfunction). However, because no penile deformity related to his diabetes mellitus has been shown, the Veteran is not entitled to a compensable rating. 38 C.F.R. § 4.20. While the September 2009 examiner noted that the Veteran might have Peyronie's disease, which resulted in the deviation of an erect penis, he did not diagnose the Veteran with such disorder, as the diagnosis was not substantiated by the Veteran's treatment records. Even had he been diagnosed with Peyronie's disease, however, the etiology or cause of Peyronie's disease is not known, and therefore cannot be attributed to his diabetes mellitus. Initial Ratings for Neuropathy of the Lower Extremities The Board now turns to whether the Veteran is entitled to higher initial ratings based upon the complications associated with diabetes mellitus. The Veteran's diabetic neuropathy of right and left lower extremities was initially rated as 0 percent disabling under Diagnostic Code 8520 for the initial rating period prior to May 2, 2008, and as 10 percent disabling for the period since May 2, 2008. Diagnostic Code 8520 pertains to paralysis of the sciatic nerve. 38 C.F.R. § 4.124a, DC 8520. The criteria for evaluating the severity or impairment of the sciatic nerve is set forth under Diagnostic Codes 8520, 8620, and 8720. Disability ratings of 10 percent, 20 percent and 40 percent are assignable for incomplete paralysis which is mild, moderate or moderately severe in degree, respectively. A 60 percent rating is warranted for severe incomplete paralysis with marked muscle atrophy. Complete paralysis of the sciatic nerve, which is rated as 80 percent disabling, contemplates foot dangling and dropping, no active movement possible of muscles below the knee, and flexion of the knee weakened or (very rarely) lost. 38 C.F.R. § 4.124a, DC 8520. Diagnostic Code 8620 and 8720 address the criteria for evaluating neuritis and neuralgia of the sciatic nerve, respectively. The criteria are consistent with the criteria for evaluating degrees of paralysis as set forth above. 38 C.F.R. § 4.124a, Diagnostic Codes 8520, 8620, 8720 (2009). After a review of the evidence, the Board finds that, for the initial rating appeal period from June 18, 2005, the Veteran's service-connected diabetic peripheral neuropathy of the right and left lower extremity has been manifested by restless leg syndrome, a burning sensation in the foot, decreased pinprick sensation and decreased vibration sense at the toes, which has been productive of no more than mild incomplete paralysis of the sciatic nerve. Such symptomatology meets the criteria for a 10 percent initial disability rating for the entire initial rating period from June 18, 2005. Clinical records dated from March 1996 to May 2, 2008 do not show symptoms or assessments of pain or loss of sensation in the lower extremities. Examination of the lower extremities consistently revealed intact sensation; however, they show that the Veteran complained of restless leg syndrome, beginning in March 1996. A May 1996 sleep study revealed moderately severe restless legs and periodic limb movements. A March 1999 study confirmed his diagnosis of moderately severe restless legs and periodic limb movements. A June 2007 statement from the Veteran's private physician indicated that his restless leg syndrome was felt to be a probable component of mild diabetic neuropathy. On VA examination in December 2003, the Veteran did not complain of any symptoms consistent with diabetic neuropathy. Neurologic testing showed that the Veteran was sensitive to the nylon line in all of his extremities and that he had temperature discrimination, vibratory sense, and position sense in all of his extremities. On VA examination in June 2005, the Veteran complained of occasional numbness in his toe. Neurologic testing revealed sensation that was intact to light touch, throughout. He was diagnosed with peripheral neuropathy, secondary to diabetes mellitus. On VA examination on May 2, 2008, the Veteran complained of a burning sensation and loss of sensation in his toes. Examination revealed marked loss of vibratory sense and diminished pain sensation in the toes of both feet. Deep tendon reflexes were intact. The diagnosis was bilateral incomplete paralysis of the sciatic nerve, mild, secondary to diabetes mellitus. Clinical records dated from May 2, 2008, to December 2009 do not demonstrate complaints or findings related to peripheral neuropathy of the lower extremities. The findings in the medical records dating from March 1996 to December 2009 support a conclusion that, although the Veteran did not experience burning and numbness associated with diabetic neuropathy in both the right and left lower extremities until later, he experienced restless leg syndrome, which has been determined to be a manifestation of his neuropathy, throughout the entire pendency of the initial rating appeal. For these reasons, the Board finds that the criteria for separate initial rating of 10 percent, but no higher for any period, for peripheral neuropathy of the right and left lower extremities, have been for the period from June 18, 2005. A separate 10 percent rating for diabetic peripheral neuropathy of both the right and left lower extremities, for the period from June 18, 2005 to May 2, 2008, is warranted. The Board also concludes that the evidence does not demonstrate that the Veteran's diabetic neuropathy of the right and left lower extremities approximates moderate incomplete neuritis, or neuralgia, such that a higher evaluation would be warranted under Diagnostic Code 8620 or Diagnostic Code 8720. The evidence demonstrates that the Veteran has mildly decreased sensation but no other neurologic abnormalities in his lower extremities. There is no evidence of decreased strength or muscle atrophy. The Board finds that the Veteran's lower extremity diabetic neuropathy symptoms are primarily sensory in nature and compatible with an incomplete paralysis of the sciatic nerve that is mild in degree. Accordingly, the Board finds that a rating in excess of 10 percent is not warranted for either extremity. The Board finds no evidence of organic changes, such as muscle atrophy or trophic changes, that would warrant a higher rating than 10 percent or demonstrate more than a mild degree of incomplete paralysis of the sciatic nerve. Accordingly, the Board finds that the Veteran's diabetic neuropathy of the lower extremities at most approximates mild incomplete neuritis, or neuralgia of the sciatic nerve, as contemplated by these Diagnostic Codes 8620, 8720. 38 C.F.R. § 4.124a. Extraschedular Consideration The Board has considered whether referral for an extra- schedular rating is warranted. The service-connected diabetes mellitus manifests with the need for a restricted diet and daily hypoglycemic agents. As discussed in the preceding section, these manifestations are contemplated by the rating criteria. Hence, the criteria for referral for consideration of an extraschedular ratings pursuant to 38 C.F.R. § 3.321(b)(1) are not met. See Bagwell v. Brown, 9 Vet. App. 337 (1996). Consideration has also been given to staged ratings (different percentage ratings for different periods of time since the effective date of service connection). Fenderson v. West, 12 Vet. App. 119 (1999). However, staged ratings are not indicated in the present case, as the Board finds that the weight of the credible evidence shows that the Veteran's service-connected diabetes mellitus has not warranted more than a 20 percent disability rating at any time during the pendency of the appeal. Additionally, the Board concludes that the Veteran has been entitled to separate 10 percent ratings, but no more, for bilateral lower extremity neuropathy, throughout the pendency of the appeal. All reasonable doubt has been resolved in favor of the Veteran in making this decision. 38 U.S.C.A. § 5107(b) (West 2002); Gilbert v. Derwinski, 1 Vet. App. 49 (1990). ORDER Service connection for the residuals of the removal of malignant melanoma from the left arm, and a lentiginous compound nevus from the chest, claimed as skin cancer, secondary to exposure to herbicide agents, is denied. Service connection for hypertension, as secondary to diabetes mellitus, is granted. The appeal for service connection for obstructive sleep apnea, as secondary to diabetes mellitus, is granted. The appeal for service connection for restless leg syndrome, to include as secondary to diabetes mellitus, having been rendered moot, is denied. An initial rating higher than 20 percent for diabetes mellitus is denied. A separate 10 percent rating for diabetic peripheral neuropathy of the right lower extremity, for the period from June 18, 2005 to May 2, 2008, is granted. A separate 10 percent rating for diabetic peripheral neuropathy of the left lower extremity, for the period from June 18, 2005 to May 2, 2008, is granted. ____________________________________________ J. Parker Acting Veterans Law Judge, Board of Veterans' Appeals Department of Veterans Affairs