Citation Nr: 21066184 Decision Date: 10/28/21 Archive Date: 10/28/21 DOCKET NO. 10-23 129 DATE: October 28, 2021 ORDER Service connection for a gastrointestinal disability, including gastroesophageal reflux disease (GERD), including as due to herbicide exposure, is dismissed. Service connection for a genitourinary disability, including benign prostatic hypertrophy (BPH) and erectile dysfunction (ED), including as due to herbicide exposure, is dismissed. Service connection for left upper peripheral neuropathy is granted. Service connection for right upper extremity peripheral neuropathy and right upper limb dystonia is granted. Service connection for left lower extremity peripheral neuropathy is granted. Service connection for right lower extremity peripheral neuropathy is granted. Service connection for bilateral carpal tunnel syndrome (CTS), including as due to herbicide exposure, is denied. Service connection for hypertension is granted. FINDINGS OF FACT 1. Prior to promulgation of a decision by the Board, the Veteran, through his representative, withdrew his pending appeals for service connection for a gastrointestinal disability and a genitourinary disability. 2. The evidence is, at a minimum, in equipoise as to whether the Veteran's bilateral upper and lower extremity peripheral neuropathy, right upper limb dystonia, and hypertension are related to the Veteran's exposure to Agent Orange during his service in Vietnam. 3. The preponderance of the evidence is against a finding that the Veteran's bilateral carpal tunnel syndrome began in service or is otherwise due to or related to his military service. CONCLUSIONS OF LAW 1. The criteria for withdrawal of the Veteran's appeal of the claim for service connection for a gastrointestinal disorder, including gastroesophageal reflux disease (GERD)and as due to herbicide exposure, have been met. 38 U.S.C. § 7105; 38 C.F.R. § 19.55. 2. The criteria for withdrawal of the Veteran's appeal of the claim for service connection for a genitourinary disability, including BPH and ED and as due to herbicide exposure, have been met. 38 U.S.C. § 7105; 38 C.F.R. § 19.55. 3. The criteria for service connection for left upper extremity peripheral neuropathy have been met. 38 U.S.C. §§ 1110, 5107; 38 C.F.R. §§ 3.102, 3.303. 4. The criteria for service connection for right upper extremity peripheral neuropathy and right upper limb dystonia have been met. 38 U.S.C. §§ 111, 5107; 38 C.F.R. §§ 3.102, 3.303. 5. The criteria for service connection for left lower extremity peripheral neuropathy have been met. 38 U.S.C. §§ 1110, 5107; 38 C.F.R. §§ 3.102, 3.303. 6. The criteria for service connection for right lower extremity peripheral neuropathy have been met. 38 U.S.C. §§ 1110, 5107; 38 C.F.R. §§ 3.102, 3.303. 7. The criteria for service connection for bilateral carpal tunnel syndrome have not been met. 38 U.S.C. §§ 1110, 5107; 38 C.F.R. §§ 3.102, 3.303. 8. The criteria for service connection for hypertension have been met. 38 U.S.C. §§ 1110, 5107; 38 C.F.R. §§ 3.102, 3.303. REASONS AND BASES FOR FINDINGS AND CONCLUSIONS The Veteran served on active duty in the U.S. Army from April 1968 to April 1970, including in Vietnam from September 1968 to September 1969. This matter comes to the Board of Veterans' Appeals (Board) on appeal from rating decisions issued in October 2008 and December 2009 by a VA Regional Office (RO). In January 2018, the Board denied all of these claims, including on the premise these disabilities are due to exposure to herbicide agents. The Veteran appealed that decision to the higher U.S. Court of Appeals for Veterans Claims (Court). Pursuant to an October 2018 Joint Motion for Remand (JMR) filed by the contesting parties, the Court vacated the Board's decision and remanded these claims back to the Board for further development and readjudication in compliance with the specified directives. In May 2019, the Board remanded the claims for acquisition of private medical records, VA treatment records from the San Juan VAMC dating from April 1970 to May 2006; all relevant VA treatment records dating from August 2017; all Employee Occupational Health Records; and all VistA imaging records. In correspondence dated in September 2021, the Veteran's representative presented evidence (an opinion from a private physician) and argument in support of the claims for peripheral neuropathy and hypertension; expressed satisfaction with all efforts to obtain extant medical records and said that further efforts would be futile; waived AOJ review of all evidence obtained since the May 2019 Board remand; and requested that the Board go ahead and decide the claims based on the evidence of record without further delay. The Board has limited the discussion below to the relevant evidence required to support its finding of fact and conclusion of law, as well as to the specific contentions regarding the case as raised directly by the Veteran and those reasonably raised by the record. See Scott v. McDonald, 789 F.3d 1375, 1381 (Fed. Cir. 2015); Robinson v. Peake, 21 Vet. App. 545, 552 (2008). 1. Service connection for a gastrointestinal disability, including gastroesophageal reflux disease (GERD), including as due to herbicide exposure, is dismissed. 2. Service connection for a genitourinary disability, including benign prostatic hypertrophy (BPH) and erectile dysfunction (ED), including as due to herbicide exposure, is dismissed. The Board may dismiss any appeal which fails to allege specific error of fact or law in the determination being appealed. 38 U.S.C. § 7105. An appeal may be withdrawn as to any or all issues involved in the appeal at any time before the Board promulgates a decision. Withdrawal may be made by the appellant or by his or her authorized representative. 38 C.F.R. § 19.55. In correspondence received by VA on September 30, 2021, the Veteran's representative (an attorney) withdrew the Veteran's pending appeal for service connection for a gastrointestinal disorder (including gastroesophageal reflux disease), and a genitourinary disorder (including prostate and erectile dysfunction). The representative specifically stated: As a preliminary matter, [the Veteran] hereby withdraws his claims of entitlement to service connection for a gastrointestinal disability and for a genitourinary disability. The Board finds that the representative's September 2021 correspondence is explicit and unambiguous; and clearly reflects the Veteran's desire to withdraw his pending appeal for service connection for a gastrointestinal disorder and a genitourinary disorder. The communication included the Veteran's name and file number. Thus, the elements for a written withdrawal have been met. As the appeal of these issues has been withdrawn, there remains no allegation of errors of fact or law for appellate consideration. Accordingly, the Board does not have jurisdiction to review these matters and they are dismissed. 38 U.S.C. § 7105(d); 38 C.F.R. § 19.55. Service Connection Service connection may be granted for a disability resulting from a disease or injury incurred in or aggravated by active service. See 38 U.S.C. § 1110; 38 C.F.R. § 3.303. "To establish a right to compensation for a present disability, a veteran must show: "(1) the existence of a present disability; (2) in-service incurrence or aggravation of a disease or injury; and (3) a causal relationship between the present disability and the disease or injury incurred or aggravated during service"the so-called "nexus" requirement." Holton v. Shinseki, 557 F.3d 1362, 1366 (Fed. Cir. 2010) (quoting Shedden v. Principi, 381 F.3d 1163, 1167 (Fed. Cir. 2004)). See also 38 C.F.R. § 3.303(d), which provides that 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. Service connection may also be granted on a presumptive basis. A veteran who, during active military, naval, or air service, served in the Republic of Vietnam during the Vietnam era, shall be presumed to have been exposed during such service to an herbicide agent, unless there is affirmative evidence to establish that such veteran was not exposed to any such agent during that service. 38 C.F.R. § 3.307(a)(6)(iii). If a veteran was exposed to an herbicide agent during active military, naval, or air service, certain enumerated diseases, such as early-onset peripheral neuropathy, shall be service-connected if the requirements of §3.307(a)(6) are met even though there is no record of such disease during service, provided further that the rebuttable presumption provisions of §3.307(d) are also satisfied. 38 U.S.C. § 1116; 38 C.F.R. § 3.309(e). Of particular relevance to this case, "delayed-onset" peripheral neuropathy, carpal tunnel syndrome, and hypertension are not enumerated conditions as presumptively associated with Agent Orange exposure. Even so, the Court in Polovick v. Shinseki, held that even though a disease is not included on the list of presumptive diseases, a nexus can still be established on direct service connection. Polovick v. Shinseki, 23 Vet. App. 48, 54 (2009). Indeed, an examiner may not summarily dismiss the possibility of a nexus merely because a condition is not listed as a presumptive condition, but rather must consider medical studies that may or may not be found persuasive, whether the Veteran has other risk factors that might be the cause of the condition for which benefits are sought, and whether the condition manifested itself in an unusual manner. Id. at 52-53. A doctor's statement that a veteran's condition "may well be" connected to Agent Orange exposure, however, is too speculative to support service connection. Id. at 54. Additionally, certain chronic diseases listed at 38 C.F.R. § 3.309(a), such as hypertension, may be service connected on a presumptive basis if manifested to a compensable degree within 1 year from the date of separation from service. See 38 U.S.C. §§ 1101, 1112; 38 C.F.R. §§ 3.307(a), 3.309(a). Presumptive periods are not intended to limit service connection to diseases so diagnosed when the evidence warrants direct service connection. 38 U.S.C. §§ 1113(b). The presumptive provisions of the statute and Department of Veterans Affairs 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). When there is an approximate balance of positive and negative evidence regarding any issue material to the determination of a matter, the Secretary shall give the benefit of the doubt to the Veteran. 38 U.S.C. § 5107(b); 38 C.F.R. § 3.102. 3. Service connection for left upper peripheral neuropathy is granted. 4. Service connection for right upper extremity peripheral neuropathy and right upper limb dystonia is granted. 5. Service connection for left lower extremity peripheral neuropathy is granted. 6. Service connection for right lower extremity peripheral neuropathy is granted. The Veteran claims entitlement to service connection for left upper and lower extremity peripheral neuropathy and right upper limb dystonia, which he posits may be related to Agent Orange exposure during service. Military records confirm that the Veteran served in Vietnam during the Vietnam war, so his exposure to Agent Orange during service is presumed. The question thus is whether the Veteran's peripheral neuropathy and dystonia is related to that Agent Orange exposure. For the reasons that follow the Board finds that service connection is warranted. Turning to the evidence of record, service treatment records (STRs) contain no record of any upper or lower extremity neurologic complaints during service, and the Veteran was not diagnosed with peripheral neuropathy or right upper limb dystonia during service. After service, the Veteran underwent psychological testing for diagnostic purposes. See August 1984 VA Neurology Clinic- Psychological Testing report. During the evaluation the Veteran reported that the reason he had reported for testing was because he was having problems with the movement of his hands and losing control easily. He elaborated, "I can't write easily and anything gets me angry and sometimes clumsy movements with my hands." He added that he had been having the problems with his hands since 1973, and that "it starts with pain and later the hands get paral[y]zed." EMG testing in February 2007 returned a diagnosis of bilateral ulnar neuropathy. In July 2008, the Veteran was afforded a VA Peripheral Nerves examination. During the examination the Veteran reported an approximate onset date of 1972. He elaborated that a few years after returning from Vietnam he noticed some involuntary movement in his hands." He also complained of pain in his right wrist that caused him to grip objects so hard that he breaks them. He added that he had been "seen by many specialists," and that his latest neurologist (Dr. M.T.G.) had diagnosed him with right limb dystonia. Physical examination found normal upper and lower extremity sensation and no motor impairment, although the examiner acknowledged that EMG testing was not done. The diagnosis was "Right limb dystonia. Problem associated with the diagnosis: upper and lower peripheral neuropathy." The examiner added that there were no clinical findings suggestive of peripheral neuropathy, and that the veteran "has right limb dystonia central nervous system movement disorder which has no relation to Agent Orange." In August 2009, the Veteran underwent an evaluation for Social Security disability purposes. During that evaluation the Veteran gave a history of being well until about 3 years after his separation from service, when he began to complain of "intermittent tonic contractions of the hands which finally became fixed in the right side," and of frequent numbness of the first 3 fingers of both hands - worse at night. The diagnosis, in pertinent part, was "dystonia of the wrist and hands (right more than left), etiology unknown." VA neurology records dated in August 2011 document the Veteran as complaining of "current-like sensation at bilateral arms since about 40 years ago... associated with poor arm coordination and involuntary movements which are worst at night and occurs also while sleeping." The Veteran also complained of persistent numbness at arms and occasionally at legs. The provider noted that the Veteran was being followed by a private neurologist who had diagnosed the Veteran with right arm dystonia and was providing Botox injections. " Electrodiagnostics" testing found "sensory neuropathy mainly axonal; differential diagnosis to consider is ganglionopathy." The radiologist added: "Although motor neuropathy not confirmed by this study, findings of neurogenic recruitment and polyphasics suggested a chronic neuropathic process." See August 2011 Electrodiagnostics Test report. The report of an Electrodiagnostic Study by VA in January 2014 also advises of bilateral median neuropathy at the hands and "clinical evidence of a possible dystonia affecting both hands." A few VA medical records refer a diagnosis of "peripheral neuropathy (secondary to carpel tunnel)." See, e.g., VA psychiatric treatment records dated in 2016 and 2017. In February 2017, the Veteran was afforded another VA Peripheral Nerves examination for an opinion as to whether the Veteran's peripheral neuropathy or carpal tunnel syndrome was incurred in or caused by service, to include exposure to herbicides. During the examination the Veteran averred that within 6-12 months of leaving his military service he started to notice episodic involuntary contractions of his left hand which for example made him crush a foam coffee cup or break a pencil with his left hand or have involuntary movements of the distal left upper extremity while doing his usual daytime office work, and that such contractions would make him have pain in the hand and he had the need to force them open to relieve the pain. The Veteran said that over time, the involuntary contraction of the left hand progressively afflicted the right hand and progressively resolved almost completely in the left hand. The Veteran also reported that in the late 1970s he began to have occasional episodes (i.e., once every one or two months) of sudden electric-like sensations in both upper extremities that would wake him up, lasting seconds; and occasional episodes (i.e., once every three to four months) of sudden electric-like sensations in both lower extremities that would wake him up, the same as he has had in his upper extremities, also lasting seconds and usually affecting the distal thighs, legs and down to his feet. The Veteran added that he started to be treated in Puerto Rico with Botox injections in the early 2000s and he would get relief of the episodic contraction for 4-6 months. The examiner observed that a March 8, 2014 Neurology Note indicated that the Veteran's contractures "had the onset in 1982." According to the examiner, the Veteran "does have clinical Hx suggestive of a peripheral neuropathy of the upper and lower extremities separate from both the Right Upper Limb Dystonia (a Central Nervous System Disorder) and separate from his Bilateral Carpal Tunnel Syndrome, afflicting the Median Nerves bilaterally," but maintained that the disorders are not related to the Veteran's Agent Orange exposure. The examiner explained that the NAS had reaffirmed the conclusion in each of its prior reports that there are no data to suggest that exposure to herbicides can lead to the development of delayed-onset chronic peripheral neuropathy many years after termination of exposure in those who did not originally experience early-onset neuropathy. The examiner noted that "[t]he committee considers a neuropathy to be early onset if abnormalities appear within a year after external exposure has ended." The examiner further averred that the "HMD report Veterans and Agent Orange: Update 2010" had concluded that there is " 'limited or suggestive evidence of an association' between herbicide exposure and 'early-onset peripheral neuropathy that may be persistent'," and noted that in response to this report, VA eliminated the requirement that acute and subacute peripheral neuropathy appear "within weeks or months' after exposure and resolve within two years." The examiner opined whether the remaining symptomatology ascribed to peripheral neuropathy of the upper and lower extremities can be attributed to herbicide exposure, and concluded that while the Veteran's own statements "position the onset of the electrical-like shocks of the upper and lower extremities in the late 70's, "it is questionable that such symptomatology could be considered early onset" because "As already stated previously, the Institute of Medicine of the National Academies of Science (IOM) has not found any evidence that chronic peripheral neuropathy developing years after exposure to herbicides is associated with herbicides exposure." The examiner further pondered, One could argue that such peripheral neuropathy, by exclusion could be due to his presumable exposure to herbicides while in Vietnam. However, the symptoms of early onset peripheral neuropathy are characterized by numbness, tingling, and motor weakness. The symptoms that he described of numbness and tingling in his first two fingers of both hands and maybe the third, (and also the pain that he described in both wrists/hands with onset in 2006, although not present now as per Veteran) could be clinically and anatomically explained by his bilateral Carpal Tunnel Syndrome. The Veteran was also afforded a VA Central Nervous System and Neuromuscular Diseases examination, which was done by the same examiner. See February 2017 VA examination report. The examiner noted that the Veteran "has sudden muscle contraction causing him to easily drops objects; mild to moderate b/l hand weakness; [and] difficulty writing due to sudden muscle contractions of the hands." The diagnosis was dystonia of the wrist and hand, which the examiner averred was less likely than not related to service because there is no record of dystonia in STRs and for some 14 years thereafter; and less likely than not related to Agent Orange exposure because "Agent Orange is not a known cause or risk factor for developing Dystonia." The examiner did, however, concede that "based on review of medical literature the exact cause of dystonia isn't known." A May 2018 VA Neuropsychological Clinic report relates a diagnosis of "peripheral neuropathy (secondary to carpel tunnel), dystonia." See also VA primary care records dated in March 2019, which show a diagnosis of "Bilateral hand dystonia." In September 2021, the Veteran's representative submitted an opinion from a private physician (Dr. P.C.) who affirmed that he had "reviewed the relevant medical records, layperson statements, medical opinions, and historical treatment records." Dr. P.C. observed that "upon completion of his service, [the Veteran] was discharged again without any evidence of significant medical issues;" and that the medical records dating from 1983 described the Veteran as presenting with problems with his hands "since 1973." According to Dr. P.C., "the historical and objective evidence in [the Veteran's] medical record supports the diagnosis of concurrent bilateral upper extremity PN as well as focal dystonia of the bilateral upper extremities since at least the early 1970s." Dr. P.C. averred that the medical literature is clear that these two entities are intrinsically linked. Dr. P.C. noted that apart from an early history of smoking as a young man, the Veteran did not have any significant risk factors for the development of his extremity disorders (such as diabetes, obesity, or an extensive history of drinking), and added, "his relatively modest smoking history is unlikely to have been sufficient to cause his... peripheral neuropathies." Dr. P.C. then averred, "In contrast to the conclusion of the February 2017 VA examiner, medical research has demonstrated that AO and TCDD exposure is a risk factor for the eventual development of both PN and dystonia," and cited to numerous studies that he said were suggestive of peripheral neuropathy up to 6 years after exposure to TCDD. Dr. P.C. also pointed out that subsequent to the February 2017 VA examination opinion, "the latest 2018 Veterans and Agent Orange Update stated, 'Toxicant exposure can result in early onset (immediate) peripheral neuropathy or delayed-onset peripheral neuropathy, which occurs years after the external exposure has ended.'" Dr. P.C. concluded, it is my medical opinion that his bilateral upper and lower extremity peripheral neuropathy and his bilateral upper extremity dystonia is, at least as likely as not, the direct result of his in-service exposure to Agent Orange and its dioxins such as TCDD. The veteran reportedly developed symptoms consistent with upper extremity neuropathy in the 1970s, which eventually progressed to lower extremity neuropathy. The relatively young age of onset (in his 20s - early 30s) is unusual for peripheral neuropathy and is consistent with toxic exposure. While his lower extremity neuropathies developed later, they also cannot be adequately accounted for by any other risk factors and are therefore more likely due to his toxic exposure. Given [the Veteran's] lack of traditional risk factors for the development of either condition, it is most likely that his toxic exposure is causative. On consideration of the evidence, the Board finds that the evidence is, at a minimum, in equipoise and, therefore, service connection is warranted. The Board does not find the evidence to support application of presumptive service connection. That is, while the Veteran clearly has Vietnam service and, therefore, conceded Agent Orange exposure, he did not have confirmed peripheral neuropathy of the upper extremities until many years after service and, therefore, did not have a diagnosis of "early onset" peripheral neuropathy. With regard to his delayed onset peripheral neuropathy, the Board finds the evidence in equipoise on whether it can be associated with his conceded Agent Orange exposure. On the one hand, the Veteran has consistently maintained he experienced symptoms of numbness and tingling in his hands since the 1970s shortly after returning from Vietnam. Although the diagnosis did not come until much later, he also did not have diagnostic testing for many years. The evidence appears to be evenly split on whether the Veteran's peripheral neuropathy is associated with non-service-related etiology, such as his carpal tunnel syndrome, versus his in-service Agent Orange exposure. The Board also notes that the most recent National Academies of Science, Engineering & Medicine (NAS) report update, as referenced in the private opinions of record, do note at least suggestive evidence of a link between delayed-onset of peripheral neuropathy and Agent Orange exposure. The Board finds relevant that the opinion of Dr. P.C., dated in September 2021 outlined the Veteran's medical and military history and found the Veteran had no other relevant risk factors for peripheral neuropathy other than Agent Orange exposure and outlined all medical literature reviewed, detailing the relevance and persuasive value of said literature. Indeed, even the February 2017 VA examiner conceded that the Veteran did not have the usual risk factors such as diabetes, alcohol intake, hypothyroidism, vitamin deficiencies, cancer, or certain medications. The February 2017 VA examiner concluded the etiology is unknown whereas Dr. P.C. concluded that in light of no other risk factors, Agent Orange is "at least as likely as not" a possible nexus. The opinion was not speculative and was thorough and extremely detailed in its rationale. According to Dr. P.C., the available research supports that TCDD exposure is associated with both early and delayed onset peripheral neuropathy and idiopathic adult-onset dystonia. Although the February 2017 VA examiner placed significant weight on the NAS Update in existence at that time, it is worth noting that the NAS Update of 2018 shows a now accepted "suggested" association between delayed onset peripheral neuropathy and Agent Orange exposure, which Dr. P.C. noted. Dr. P.C. recited numerous learned studies in support of his opinion and, with regard to the Veteran's peripheral neuropathy, advised that the NAS guidance has since changed to reflect the possibility that "toxicant exposure can result in early onset (immediate) peripheral neuropathy or delayed-onset peripheral neuropathy, which occurs years after the external exposure has ended." On the other hand, Dr. P.C. did not personally examine the Veteran in comparison to prior examinations of record and his opinion does not change the fact that the evidence does not show in-service evidence of peripheral neuropathy or a diagnosis of peripheral neuropathy for many years after service. Aside from the September 2021 opinion, the VA medical opinions of record appear to associate the Veteran's neuropathy with his carpal tunnel syndrome. At a minimum, the Board finds the evidence in equipoise and, therefore, the Veteran is therefore entitled to the benefit of the doubt. Entitlement to service connection for bilateral upper and lower extremity peripheral neuropathy and right upper limb dystonia on a direct basis is accordingly warranted and to this extent the appeal is granted. 38 C.F.R. § 3.303(d). 7. Service connection for bilateral carpal tunnel syndrome (CTS), including as due to herbicide exposure, is denied. The Veteran has also requested service connection for carpal tunnel syndrome, including as due to Agent Orange exposure during service. The Board further notes that, relevantly, the Veteran served as a "clerk typist" in the military. Even so, for the reasons that follow, the Board finds that the claim is not established. Turning to the evidence of record, military records confirm that the Veteran served in Vietnam during the Vietnam war, and his exposure to Agent Orange during service is presumed and his DD-214 confirms his MOS as a clerk typist. However, STRs contain no record of any upper or lower extremity neurologic complaints during service, and the Veteran was not diagnosed with carpal tunnel syndrome during service. After service, the Veteran underwent psychological testing for diagnostic purposes. See August 1984 VA Neurology Clinic- Psychological Testing report. During the evaluation the Veteran reported that the reason he had reported for testing was because he was having problems with the movement of his hands and losing control easily. He elaborated, "I can't write easily and anything gets me angry and sometimes clumsy movements with my hands." He added that he had been having the problems with his hands since 1973, and that "it starts with pain and later the hands get paral[y]zed." EMG testing by a private provider in February 2007 returned a diagnosis of, inter alia, bilateral carpal tunnel syndrome. In July 2008, the Veteran was afforded a VA Peripheral Nerves examination. There is no mention of carpal tunnel syndrome in the ensuing report. In August 2009, the Veteran underwent an examination for Social Security disability purposes. The diagnosis, in pertinent part, was "bilateral carpal tunnel syndrome by history." VA neurology records dated in August 2011 describe the Veteran as complaining of bilateral arm symptoms since about 40 years ago. VA primary care records dated in 2013 show a diagnosis of bilateral carpal tunnel syndrome and note that the Veteran was wearing wrist splints. An Electrodiagnostic Study by VA in January 2014 found bilateral median neuropathy at the hands and "clinical evidence of a possible dystonia affecting both hands." In February 2017, the Veteran was afforded a VA Peripheral Nerves examination for an opinion as to whether the Veteran's peripheral neuropathy or carpal tunnel syndrome was incurred in or caused by service, to include exposure to herbicides. During the examination the Veteran averred that within 6-12 months of leaving his military service he started to notice episodic involuntary contractions of his left hand which for example made him crush a foam coffee cup or break a pencil with his left hand or have involuntary movements of the distal left upper extremity while doing his usual daytime office work, and that such contractions would make him have pain in the hand and he had the need to force them open to relieve the pain. The Veteran said that over time, the involuntary contraction of the left hand progressively afflicted the right hand and progressively resolved almost completely in the left hand. The Veteran also reported that in the late 1970s he began to have occasional episodes (i.e., once every one or two months) of sudden electric-like sensations in both upper extremities that would wake him up, lasting seconds. The Veteran added that he started to be treated in Puerto Rico with Botox injections in the early 2000s and he would get relief of the episodic contraction for 4-6 months. The examiner observed that a March 8, 2014 Neurology Note indicated that the Veteran's contractures "had the onset in 1982." The diagnosis was, inter alia, bilateral carpal tunnel syndrome, which the examiner said was not related to service or the Veteran's Agent Orange exposure. The examiner noted that the symptoms of numbness and tingling in the first two fingers of both hands and maybe the third, (and also the pain that the Veteran described in both wrists/hands with onset in 2006) could be clinically and anatomically explained by his bilateral Carpal Tunnel Syndrome. The examiner added, clinically, such syndrome in his case is felt to have been due to the type of job that he performed for close to 35 years, working in the financial sector doing office work with his hands, writing frequently and for hours. Such was the fundamental reason for which he retired from such job; inability to keep using his hands in a repeated basis. And there is no evidence on him of such specific symptomatology during his years in service. Therefore from the strict clinical standpoint one can reasonably exclude that herbicide exposure has been the cause of such Carpal Tunnel Syndrome. In September 2021, the Veteran's representative submitted an opinion from a private physician (Dr. P.C.) who affirmed that he had "reviewed the relevant medical records, layperson statements, medical opinions, and historical treatment records." Dr. P.C. did not opine regarding the etiology of the Veteran's carpal tunnel syndrome. Based on the evidence of record, the Board finds that the claim is not substantiated. Regarding the propounded theory of service connection due to Agent Orange exposure, although the provisions of 38 C.F.R. § 3.307(a)(6)(iii) are met, carpal tunnel syndrome is not on the list of diseases associated with herbicide exposure, so service connection under the presumptive provisions of 38 C.F.R. § 3.309(e) is not possible. Even so, the Veteran may substantiate his claim if he can show that his herbicide exposure actually caused his carpal tunnel syndrome. See 38 U.S.C. § 1113(b); 38 C.F.R. § 3.303(d) (the availability of service connection on a presumptive basis does not preclude consideration of service connection on a direct basis); Combee v. Brown, 34 F.3d 1039, 1043-44 (1994) (providing that even when presumptive service connection is not applicable, direct service connection may be considered). This he has not done. The Veteran has presented no evidence that supports his contention that his carpal tunnel syndrome may be related to his in-service exposure to Agent Orange. Moreover, medical opinion evidence militates against such nexus. The February 2017 VA examiner avers that the Veteran's carpal tunnel syndrome is not related to the Veteran's Agent Orange exposure. He specifically stated, "from the strict clinical standpoint one can reasonably exclude that herbicide exposure has been the cause of such Carpal Tunnel Syndrome." The record contains no medical opinion to the contrary. Additionally, there is no record of carpal tunnel syndrome in the STRs, and no clinician has related the Veteran's carpal tunnel syndrome to any other incident of his military service, including his various military duties. On the contrary, the February 2017 VA examiner noted that there was no record of carpal tunnel syndrome in service and expressly stated that the Veteran's carpal tunnel syndrome was not related to his service. The examiner considered the Veteran's statements of when the symptoms began and his in-service duties (and the in-service exposure to Agent Orange exposure), but felt the Veteran's over 30 year post-service clerical occupation was more relevant to the development of his carpal tunnel syndrome many years after service. To the extent that the Veteran's statements are offered as a nexus opinion between his carpal tunnel syndrome and his in-service duties and/or exposure to Agent Orange, it is noted that lay opinions in medically complex cases, such as here, are limited to inferences which are rationally based on a claimant's perception and that do not require specialized knowledge. There is no lay complaint or medical evidence of any carpal tunnel syndrome until many years after the Veteran's separation from service; and the Veteran is not qualified through specialized knowledge, education, training, or experience to offer a retrospective medical opinion. The Veteran's lay contention of a nexus is thus mere speculation and not probative. See Bloom v. West, 12 Vet. App. 185, 187 (1999) (holding that statements favorable to the veteran's' claim that do little more than suggest a possibility are too speculative to establish the required nexus for service connection). The Board accordingly finds that the preponderance of the evidence is against the claim for carpal tunnel syndrome under all expressly and reasonably raised theories of entitlement and the appeal is denied. 38 C.F.R. §§ 3.303, 3.309. 8. Service connection for hypertension is granted. The Veteran has also requested service connection for hypertension, including as due to Agent Orange exposure during service. Turning to the evidence of record, STRs contain no record of a blood pressure problem, and the Veteran was not diagnosed with hypertension during service; however, the Veteran currently has a confirmed diagnosis of hypertension. See, e.g., December 2006 Ambulatory Blood Pressure Report. In February 2017, the Veteran was afforded a VA Hypertension examination for an opinion as to whether the Veteran's hypertension was incurred in or caused by service, to include exposure to herbicides. During the examination the Veteran reported that he was diagnosed with hypertension "approximately in 2006," and that he was taking oral hypertensive medication. The diagnosis was hypertension, which the examiner said was less likely than not related to service because of the 36 year interim between service and diagnosis; and less like than not related to the Veteran's Agent Orange exposure "based on Review of Medical literature herbicide agents, including Agent Orange is not a known cause or risk factor for developing hypertension." In September 2021, the Veteran's representative submitted an opinion from a private physician (Dr. P.C.) who affirmed that he had "reviewed the relevant medical records, layperson statements, medical opinions, and historical treatment records." Dr. P.C. stated that he disagreed with the conclusions of the February 2017 VA examining nurse and averred that those conclusions were based on an inaccurate and incomplete review of the medical literature. Dr. P.C. explained that prior studies were inconclusive, and pointed out that in 2018 the Committee to Review the Health Effects in Vietnam Veterans of Exposure to Herbicides (Veterans and Agent Orange Update 2018) changed their classification and concluded, "the information now assembled constitutes sufficient evidence of an association between exposure to at least one of the [chemicals of interest] and hypertension." Dr. P.C. noted that apart from an early history of smoking as a young man, the Veteran did not have any significant risk factors for the development of his hypertension (such as diabetes, obesity, or an extensive history of drinking), and added, "his relatively modest smoking history is unlikely to have been sufficient to cause his hypertension." Dr. P.C., then averred, "since [the Veteran] has minimal other risk factors for the development of hypertension, his exposure to TCDD is, as likely as not, the cause of his current hypertension." According to Dr. P.C., the medical literature is coming to a clear consensus that exposure to TCDD leads to increased rates of chronic cardiovascular diseases including hypertension and its complications. Dr. P.C.reiterated, "When considering the consensus in the medical literature showing a relationship between hypertension and TCDD exposure, it is also my medical opinion that [the Veteran's] hypertension is, more likely than not, due to his history of Agent Orange exposure from his active-duty service in the Republic of Vietnam." For the reasons that follow, the Board will resolve all reasonable doubt and grant service connection for hypertension. As for service connection on a presumptive basis under the propounded theory of entitlement, while the provisions of 38 C.F.R. § 3.307(a)(6)(iii) are met, hypertension is not on the list of diseases associated with herbicide exposure, so service connection under those provisions is not possible. There is also no diagnosis of hypertension in the year after the Veteran's separation from service, so service connection under the presumptive provisions of 38 C.F.R. § 3.309(a) is not warranted. However, the Board finds that there is an approximate balance of post-service evidence for and against the claim for hypertension on a direct basis. See Combee, 34 F.3d 1039, 1043-44 (providing that even when presumptive service connection is not applicable, direct service connection may be considered); See also 38 C.F.R. § 3.303(d). In that regard, both the February 2017 VA examiner and the September 2021 private opinion considered the Veteran's military and medical history and noted medical literature in rendering their respective and contrary opinions. The February 2017 VA examiner placed great emphasis on the fact that the Veteran was diagnosed with hypertension until 36 years after service and noted that the most recent NAS Update at that time did not associate hypertension with Agent Orange exposure. In contrast, the September 2021 private opinion pointed out that the Veteran had none of the other usual risk factors seen for patients who develop hypertension and that since 2017, the NAS had released a more recent update in 2018 indicating "sufficient evidence of an association" between Agent Orange and hypertension. Given the Veteran's particular medical history, the lack of other risk factors, and the body of medical literature, Dr. P.C. found it "at least as likely as not" that the Veteran's hypertension was due to his Agent Orange exposure. At a minimum, the Board finds the evidence in equipoise and, therefore, the Veteran is therefore entitled to the benefit of the doubt. Entitlement to service connection for hypertension on a direct basis is accordingly warranted and the appeal is granted. 38 C.F.R. § 3.303(d). SHEREEN M. MARCUS Veterans Law Judge Board of Veterans' Appeals Attorney for the Board P. Childers, Counsel The Board's decision in this case is binding only with respect to the instant matter decided. This decision is not precedential and does not establish VA policies or interpretations of general applicability. 38 C.F.R. § 20.1303.