Citation Nr: 1751963 Decision Date: 11/14/17 Archive Date: 11/22/17 DOCKET NO. 12-24 326 ) DATE ) ) On appeal from the Department of Veterans Affairs Regional Office in Lincoln, Nebraska THE ISSUES 1. Entitlement to service connection for headaches, to include as secondary to service-connected sleep apnea. 2. Entitlement to service connection for a psychiatric disorder including memory impairment, and to include as secondary to service-connected obstructive sleep apnea. REPRESENTATION Appellant represented by: Veterans of Foreign Wars of the United States ATTORNEY FOR THE BOARD A. Yaffe, Associate Counsel INTRODUCTION The Veteran had active service from November 1983 to February 1992. These matters come before the Board of Veterans' Appeals (Board) on appeal from May 2011 and June 2011 rating decisions of the Department of Veterans Affairs (VA) Regional Office (RO) in Lincoln, Nebraska. In December 2014, the Board granted entitlement to service connection for obstructive sleep apnea, and remanded the service connection claims for a psychiatric disorder and headaches for additional development and consideration. In June 2016, the Board remanded the claims in order to obtain addendum medical opinions in connection with the Veteran's claims. The issue of entitlement to service connection for headaches, to include as secondary to service-connected sleep apnea, is addressed in the REMAND portion of the decision below and is REMANDED to the Agency of Original Jurisdiction (AOJ). FINDINGS OF FACT 1. A prior diagnosis of adult-onset dysthymia is in full remission and not related to military service. 2. The weight of the competent evidence is against a finding that the Veteran has a currently diagnosed psychiatric disorder, including one productive of memory impairment. (CONTINUES ON NEXT PAGE) CONCLUSION OF LAW The criteria to establish service connection for a psychiatric disorder, including memory loss, and to include as secondary to service-connected sleep apnea, have not been met. 38 U.S.C.A. §§ 1110, 1131, 5107 (West 2014); 38 C.F.R. §§ 3.303, 3.307, 3.309, 3.310 (2017). REASONS AND BASES FOR FINDINGS AND CONCLUSION Duties to Notify and Assist In this case, neither the Veteran nor his representative has raised any issues with the duty to notify or duty to assist. See Scott v. McDonald, 789 F.3d 1375, 1381 (Fed. Cir. 2015) (holding that "the Board's obligation to read filings in a liberal manner does not require the Board . . . to search the record and address procedural arguments when the veteran fails to raise them before the Board."); Dickens v. McDonald, 814 F.3d 1359, 1361 (Fed. Cir. 2016) (applying Scott to a duty to assist argument). Factual Background In an undated record (presumably dated in 2012 based on the notation of the Veteran's age at the time), the Veteran underwent a private psychological assessment "to investigate specifically the phenomenon of [his] memory problems." Upon a comprehensive mental status consultation, the psychologist noted that there were "symptoms of mild depression and even milder anxiety," but indicated that this was "subject to very extreme and concrete variability depending again on whether he [the Veteran] was talking about his military experiences or not." The psychologist ruled out posttraumatic stress disorder (PTSD) and amnestic disorder, and concluded that no mental condition was present. However, it was noted that there were some signs of exposure to War and unspecified serious trauma. The psychologist stated that the Veteran was "the type of man who listens well, responds at a very intellectually responsive manner, and without any knowledge of his prior difficulty in the service or his stated memory difficulty he appears to be with all due respect to his own phenomenological reporting normal." The psychologist further noted that "one could look through the possibility of his having acquired possible nerve damage due to gas drainage which he [the Veteran] described in a very vague manner." It was further indicated that there also could be some degree of difficulty with extreme memory loss because of depression and or anxiety, "but these were really not demonstrated in any other facet of his intellectual response" and the psychologist added that it would probably have to be ruled out" although it was recommended that the Veteran undergo an intensive medical evaluation with a specialist in a neurological functioning. In January 2012, the Veteran underwent a neurology assessment at the Neurology Associates of Great Plains, which was noted to be based on the Veteran's self-report. The Veteran reported that the onset of his memory impairment has been sudden ("relatively suddenly" and has been present for the last 21 years reports being exposed to pyridostigmine bromide in 1991 while serving in the army in Saudi Arabia and reported that he probably was "exposed to nerve agents because our alarms did go off numerous times"). The examiner noted that the memory impairment was characterized as a loss of recent memory and a loss of remote memory. The symptoms have been associated with headache (4-5 "minor" headaches per week and 2-3 headaches "that bother me" per month), but have not been associated with alcoholism, cerebrovascular disease, depression, drug addiction, epilepsy, history of encephalitis, history of meningitis, intellectual deterioration, nausea, and neck stiffness or rigidity. There was no indication of topographical disorientation, hallucination or psychosis, personality changes, or depression during the assessment. The examiner noted that the Veteran had a minor head injury in 1986 when playing football associated with loss of consciousness (LOC), as well as a car accident a few years later but without LOC. During the assessment, the Veteran did not show signs of memory loss and the examiner noted that he "excelled in his overall gross assessment of his memory and cognitive function." The examiner indicated that he has reasons to have memory loss such as family history and chronic untreated snoring/sleep apnea, but there are no objective findings to specifically link those to current memory loss. The examiner noted that the Veteran should still be tested for reversible causes for dementia and added that it could not be ruled out that exposure to nerve gas has effect on the Veteran's memory dysfunction. However, the examiner noted that the Veteran was resistant to his explanation, which concluded that without substantial proof of memory disturbance and the "unknown nerve gas" trace exposure, the Veteran's case cannot be proved or disproved. A few days after the neurological assessment, the Veteran underwent a MRI of the brain with the impression of "normal brain MRI," and a lab workup was normal as well. In a May 2012 statement, a fellow servicemember indicated that he "started noticing that [the Veteran] would start becoming confused and would start forgetting basic -unit information" and noted that at the time he "placed this as stress with the deployment but have since changed [his] opinion of that." In June 2012, the Veteran underwent a VA compensation examination for PTSD. The examiner found no support for a diagnosis of PTSD, but rather diagnosed the Veteran with dysthymia, adult-onset, and signs of schizoid personality traits. The examiner noted that the Veteran's daughter died from cancer a year prior to the examination. The Veteran reported that while deployed in Panama "they would be driving by the outskirts of the city and they would be shooting at you...it was port shots...no one was hurt or killed." The Veteran additionally reported that four Panamanian police officers were killed and although he was not involved in seeing their death he had seen a bloody uniform. Lastly, the Veteran noted that "the entire Gulf War" especially Scud and chemical agent alarms that went off all the time. After the mental examination, the VA examiner concluded that the Veteran did not meet the criteria for PTSD, but rather noted that the Veteran's testing results were consistent with "a diagnosis of adult-onset dysthymia, or in other words, depression that has been ongoing for at least two years in duration," especially due to his daughter's death and dealing with the trials and tribulations of families who their loved ones were killed during his work with the police force. The examiner then opined that the Veteran's adult-onset dysthymia was not due to military service as there was no evidence of depression during service. In August 2012, the Veteran sent an e-mail to Dr. R.H. who conducted research on exposure to nerve gases during the Gulf War and its impact on Gulf War Syndrome. The Veteran noted that his primary issues were migratory non-inflammatory joint pain, memory/cognitive issues, and sleep apnea. In his reply e-mail, Dr. R.H. stated that if the Veteran was at King Khalid Military City (KKMC) during the first week of the air way and heard nerve agent alarms sounding in the area, he was likely exposed to low level sarin. The doctor added that the research indicated that the Veteran's symptoms are due to changes in the brain from that exposure. However, the doctor noted that no testing or treatment was available and that they were working on a diagnostic blood test and identifying targets in brain physiology for medication to eliminate the symptoms. In an October 2012 statement, the Veteran's spouse indicated that the Veteran had had memory problems since his return from the Gulf War. She noted that the memory loss was random and of both short and remote memories, which leads to his increased frustration and loss of patience. In an October 2012 statement, another servicemember stated that he remembered the Veteran to be outgoing and very attentive, but when he met him in May 2012 for a reunion he was not the outgoing person he remembered, but rather was very reserved. He further noted that the group was discussing past events but the Veteran had a hard time remembering those events. An additional buddy statement noted that in August 1989, while the servicemember was driving a vehicle during training, the Veteran hit his head on a bullet resistant windshield which caused the windshield to "spider web," but the Veteran refused treatment because he was afraid to be reprimanded for not wearing "Kevlar helmet" in the vehicle. He added that the Veteran suffered from headaches after that incident. In April 2013, the RO obtained an addendum medical opinion from the June 2012 examiner after the Veteran provided a statement claiming a nervous condition due to an undiagnosed illness that causes memory loss and cognitive deficits. The examiner opined that the Veteran's condition was not related to service and explained that a June 2012 record showed an anxiety score of 20 which was not consistent with anxiety, NOS, generalized anxiety, OCD, adjustment disorder with anxiety, or other anxiety spectrum disorder. The examiner further noted that the word "nervous" is "associated with an anxiety disorder per an exact diagnosis of DSM-IV" and the Veteran's valid testing was not consistent with any nervous condition or anxiety disorder. The examiner further noted that the Veteran's reported symptoms were not related to the diagnosed mental disorder from June 2012 (e.g., adult onset dysthymia). Specifically, the examiner noted that upon review of the January 2012 neurological assessment, it was apparent that all testing and findings were overall within normal limits. The examiner further noted that the attention test, which showed "somewhat lowered" scores, was consistent with dysthymia, which has specific criteria of problems with concentration. The examiner indicated that the neurological examination was solely based on the Veteran's self-report which was subjective and that the emotional factors caused the lower concentration and attention scores. Lastly, the VA examiner indicated that the Veteran's symptoms and problems with concentration or memory may be related to untreated sleep apnea since feeling fatigued from sleep apnea and not breathing for periods of time have been linked to some memory problems although "causation has not been determined but links have been established in the research." In December 2014, the Board remanded the case in order to obtain an additional medical opinion after finding inconclusive the previous opinions as to whether the Veteran's memory impairment was caused or aggravated by his service-connected sleep apnea (both the January 2012 neurology assessment and the April 2013 addendum opinion noted that there could be a link between memory loss and sleep apnea). In response, in March 2015, the Veteran underwent an additional VA mental examination, during which the examiner found the Veteran does not have a psychiatric disorder by the DSM-IV or DSM-V, nor does he have any memory impairment; thus, the examiner necessarily determined that the claimed psychiatric disorder or memory impairment could not have been caused by, incurred by, proximately related to, or aggravated by sleep apnea. The March 2015 VA examiner also noted the Veteran had historically exhibited dysthymic disorder, which had fully remitted. An additional opinion was obtained in April 2015, in which the examiner concurred that the Veteran currently has no mental disorder. Notably, the examiner stated that the Veteran's immediate memory was exactly where it should be based on the testing and evaluations on record. The examiner added that the Veteran's past mental health history of depression was in full remission and his associated memory impairment was acute, transient, and self-limited. The examiner ultimately concluded that it was less likely than not that the Veteran's claimed psychiatric disorder, to include memory impairment was related to and/or aggravated by his time in military service and/or sleep apnea. In April 2015, the Board remanded the case for in order to obtain yet another addendum opinion. Specifically, the Board found that despite not having a current diagnosis, a nexus opinion was necessary for the psychiatric disorders that were diagnosed during the pendency of the appeal (i.e., schizoid personality traits and dysthymic disorder). Subsequently, in October 2016, an addendum medical opinion was obtained. The examiner initially noted that schizoid personality traits were not a diagnosis (the Board finds that the June 2012 examiner noted "N/A" for the diagnostic code under Axis II). However, the examiner added that "Even if Schizoid Personality Disorder were a diagnosis made, which I do not make, that personality disorders are not caused by or aggravated by Sleep Apnea." The examiner explained that no professional peer-related research demonstrates "how this would happen in scientific reality for causation or aggravation as specific to personality traits\disorder." Furthermore, the examiner noted that there was no current diagnosis of depression. The examiner indicated that "the Veteran had been noted for multiple psychosocial stressors to include dealing with families of loved ones who had been killed during his service with the Police Department and that his daughter had passed from cancer in the past year." The examiner further stated that it was less likely than not that the historical diagnosis of adult onset dysthymia was incurred in, caused by or aggravated by his sleep apnea. The examiner explained that the Veteran actually went into full remission from the dysthymia, and it therefore could not have been aggravated because aggravation means worsening over time and, in this case, there was full abatement and not a worsening. Lastly, the VA examiner noted that the etiology of the Veteran's depressive disorder when diagnosed in 2012 was more likely than not related to the very serious nature of his job with the police department and the death of his daughter which were both substantial and not to his military service. Service Connection - Applicable Laws and Regulations Service connection may be granted for a disability resulting from disease or injury incurred in or aggravated by active military, naval, or air service. 38 U.S.C.A. §§ 1110, 1131; 38 C.F.R. § 3.303(a). 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. 38 C.F.R. § 3.303(d). In order to establish the service connection for the claimed disorder, there must be (1) medical evidence of a current disability; (2) medical or, in certain circumstances, lay evidence of in-service incurrence or aggravation of a disease or injury; and (3) a causal connection between the claimed aggravation of a disease or injury and the current disability. See Shedden v. Principi, 381 F.3d 1163 (Fed. Cir. 2004). Where the evidence shows a "chronic disease" in service or "continuity of symptoms" after service, the disease shall be presumed to have been incurred in service. For the showing of "chronic" disease in service, there is required a combination of manifestations sufficient to identify the disease entity, and sufficient observation to establish chronicity at the time. With chronic disease as such in service, subsequent manifestations of the same chronic disease at any later date, however remote, are service-connected, unless clearly attributable to intercurrent causes. If a condition noted during service is not shown to be chronic, then generally, a showing of "continuity of symptoms" after service is required for service connection. 38 C.F.R. § 3.303 (b); Walker v. Shinseki, 708 F.3d 1331 (Fed. Cir. 2013). Additionally, where a veteran served ninety days or more of active service, and certain chronic diseases, such as psychoses, become manifest to a degree of 10 percent or more within one year after the date of separation from such service, such disease shall be presumed to have been incurred in service, even though there is no evidence of such disease during the period of service. Psychoses are among the listed diseases for which this presumption is warranted. 38 U.S.C.A. §§ 1101, 1112, 1113; 38 C.F.R. §§ 3.307, 3.309(a). 38 C.F.R. § 3.384 defines psychosis as including a brief psychotic disorder, delusional disorder, psychotic disorder due to general medical condition, psychotic disorder, not otherwise specified, schizoaffective disorder, schizophrenia, schizophreniform disorder, shared psychotic disorder, and substance-induced psychotic disorder. 38 C.F.R. § 3.384. While the disease need not be diagnosed within the presumption period, it must be shown, by acceptable lay or medical evidence, that there were characteristic manifestations of the disease to the required degree during that time. Id. The existence of a current disability is the cornerstone of a claim for VA disability compensation. See Degmetich v. Brown, 104 F. 3d 1328 (1997); Brammer v. Derwinski, 3 Vet. App. 223, 225 (1992). Service connection for PTSD requires the following three elements: (1) a current medical diagnosis of a psychiatric disorder (2) credible supporting evidence that the claimed in-service stressor(s) actually occurred, and (3) medical evidence of a causal relationship between current symptomatology and the specific claimed in-service stressor(s). See 38 C.F.R. § 3.304(f). In adjudicating a claim for service connection for a psychiatric disorder, to include PTSD, the Board is required to evaluate evidence based on places, types, and circumstances of service, as shown by the veteran's military records and all pertinent medical and lay evidence. Hayes v. Brown, 5 Vet. App. 60, 66 (1993); see also 38 U.S.C.A. § 1154(a); 38 C.F.R. § 3.304(f). The evidence necessary to establish the occurrence of an in-service stressor for PTSD will vary depending on whether or not the veteran "engaged in combat with the enemy." Id. If VA determines that the veteran engaged in combat with the enemy and that the alleged stressor is related to combat, then the veteran's lay testimony or statements are accepted as conclusive evidence of the occurrence of the claimed stressor. 38 U.S.C.A. § 1154(b); 38 C.F.R. § 3.304(f). No further development or corroborative evidence is required, provided that the claimed stressor is "consistent with the circumstances, conditions, or hardships of the veteran's service." Id. If, however, VA determines that the veteran did not engage in combat with the enemy or that the alleged stressor is not related to combat, the veteran's lay testimony by itself is not sufficient to establish the occurrence of the alleged stressor. Instead, the record must contain service records or other evidence to corroborate the veteran's testimony or statements. See Moreau v. Brown, 9 Vet. App. 389, 394 (1996). The question of whether a veteran was exposed to a stressor in service is a factual one, and VA adjudicators are not bound to accept uncorroborated accounts of stressors or medical opinions based upon such accounts. Wood v. Derwinski, 1 Vet. App. 190 (1991), aff'd on reconsideration, 1 Vet. App. 406 (1991). Hence, whether a stressor was of sufficient gravity to cause or support a diagnosis of a psychiatric disorder, to include PTSD is a question of fact for medical professionals and whether the evidence establishes the occurrence of stressors is a question of fact for adjudicators. Service connection may also be established on a secondary basis for a disability that is proximately due to or the result of a service-connected disease or injury. 38 C.F.R. § 3.310. Establishing service connection on a secondary basis requires evidence sufficient to show (1) that a current disability exists and (2) that the current disability was either (a) caused by or (b) aggravated by a service-connected disability. See 38 C.F.R. § 3.310; see also Allen v. Brown, 7 Vet. App. 439 (1995). Lay assertions may serve to support a claim for service connection by establishing the occurrence of observable events or the presence of disability or symptoms of disability subject to lay observation. 38 U.S.C.A. § 1154(a) (West 2014); 38 C.F.R. § 3.303(a); Jandreau v. Nicholson, 492 F.3d 1372 (Fed. Cir. 2007); see also, Buchanan v. Nicholson, 451 F. 3d 1331, 1336 (Fed. Cir. 2006) (addressing lay evidence as potentially competent to support presence of disability even where not corroborated by contemporaneous medical evidence). The United States Court of Appeals for the Federal Circuit (Federal Circuit) has clarified that lay evidence can be competent and sufficient to establish a diagnosis or etiology when (1) a lay person is competent to identify a medical condition; (2) the lay person is reporting a contemporaneous medical diagnosis, or (3) lay testimony describing symptoms at the time supports a later diagnosis by a medical professional. Davidson v. Shinseki, 581 F.3d 1313 (Fed. Cir. 2009). In rendering a decision on appeal the Board must analyze the credibility and probative value of the evidence, account for the evidence which it finds to be persuasive or unpersuasive, and provide the reasons for its rejection of any material evidence favorable to the claimant. Gabrielson v. Brown, 7 Vet. App. 36, 39-40 (1994); Gilbert v. Derwinski, 1 Vet. App. 49, 57 (1990). Competency of evidence differs from weight and credibility. Competency is a legal concept determining whether testimony may be heard and considered by the trier of fact, while credibility is a factual determination going to the probative value of the evidence to be made after the evidence has been admitted. Rucker v. Brown, 10 Vet. App. 67, 74 (1997); Layno v. Brown, 6 Vet. App. 465, 469 (1994); see also Cartright v. Derwinski, 2 Vet. App. 24, 25 (1991) ("although interest may affect the credibility of testimony, it does not affect competency to testify"). The Board may weigh the absence of contemporaneous medical evidence against the lay evidence in determining credibility, but the Board cannot determine that lay evidence lacks credibility merely because it is unaccompanied by contemporaneous medical evidence. Buchanan v. Nicholson, 451 F.3d 1331 (Fed. Cir. 2006). Analysis In consideration of all evidence of record, the Board concludes that the criteria to establish service connection for a psychiatric disorder are not met. In so finding, the multiple VA examinations as noted above reflect no current psychiatric disorder. Indeed, as indicated in the above-noted medical evidence, the June 2012 VA examiner determined that the Veteran had adult onset dysthymia that had its onset years after service due to family and work issues, and not due to military service. The examiner added in the 2013 addendum that the Veteran's test results were not consistent with any nervous or anxiety disorder. Additionally, the 2012 neurologic evaluation showed no evidence of memory impairment. The March 2015 VA examiner reiterated that the Veteran does not meet the DSM criteria for any psychiatric disorder and does not have any memory impairment; the examiner further added that the Veteran's dysthymic disorder, previously diagnosed, was now in full remission. The April 2015 and October 2016 opinions concurred that the Veteran does not have a current psychiatric disorder. The Board finds that collectively, the VA opinions of record are adequate and probative on the issue of a current disability. Notably, the Veteran has not identified any outstanding, relevant evidence that would document a current disability. The Board notes that the Veteran, as a lay person, is competent to note what he experiences, including having observable psychiatric symptoms such as a depressed mood. See Layno v. Brown, 6 Vet. App. 465, 467-69 (1994). Similarly, the Veteran's spouse and fellow service members who submitted statements are competent to report the Veteran's behavior that they witnessed upon his return from service. However, in this case, the question as to whether any relevant symptoms meet the criteria for a diagnosis is a complex medical question. It is different from a separated shoulder, varicose veins, or flat feet, which are capable of direct lay observation. See e.g. Jandreau v. Nicholson, 492 F.3d 1372 (Fed. Cir. 2007). That is, appropriate expertise is required to determine whether the Veteran's psychiatric symptoms are of such impairment to arise to a diagnosis under medical principles. In the present case, there is nothing in the record to suggest that the Veteran or his fellow service members who provided lay statements have the appropriate training, experience, or expertise to render psychiatric diagnoses. See 38 C.F.R. § 3.159 (a)(1) (2017). Indeed, they are not competent to provide a psychiatric diagnosis, as such is not readily subject to lay observation. See Barr v. Nicholson, 21 Vet. App. 303 (2007). Accordingly, in this circumstance, the Board gives more weight to the VA mental health examiners who concluded that the Veteran does not have a current diagnosis of a psychiatric disorder, and gives less weight to lay statements of record regarding current psychiatric disability. In summary, the Board finds that the weight of the lay and medical evidence shows that the Veteran does not have a current psychiatric disorder, including one productive of memory impairment. To the extent that adult-onset depression was diagnosed during the pendency of the appeal, the VA examiner determined that it was not related in any way to the Veteran's military service, and the VA examiners concur that it is in full remission. The Board does observe that the Veteran has been shown to exhibit some schizoid personality traits, but not a personality disorder per se. At any rate, even if a personality disorder had been diagnosed, VA compensation may not be paid for such disorder, as it is specifically excluded as a disease or injury within the meaning of applicable legislation providing for VA compensation benefits. Thus, generally speaking, a personality disorder is not service connectable as a matter of express VA regulation. See 38 C.F.R. §§ 3.303 (c), 4.9, 4.127 (2017). . Significantly, the laws authorizing Veterans' benefits provide benefits only where there is current disability, as identified by a medical diagnosis. In the absence of proof of a current disability, there is no valid claim of service connection. Brammer v. Derwinski, 3 Vet. App. 223, 225 (1992). The Board concludes that the Veteran in this case has not presented competent evidence showing that he has a current psychiatric disorder. See 38 U.S.C. § 5107 (a) ("[A] claimant has the responsibility to present and support a claim for benefits."); Fagan v. Shinseki, 573 F.3d 1282, 1287 (Fed. Cir. 2009) (holding that it is the claimant's general evidentiary burden to establish all elements of the claim). As the threshold element has not been met, the service connection claim on a direct basis must be denied. In light of the finding of no current disability, the Veteran's claim on a secondary basis must also fail. The preponderance of the evidence is against the claim, and the benefit-of-the doubt standard of proof does not apply. 38 U.S.C.A. § 5107 (b) (2017). ORDER Entitlement to service connection for a psychiatric disorder, to include memory impairment, and to include as secondary to service-connected obstructive sleep apnea is denied. REMAND An additional remand is necessary in order to obtain a new addendum opinion with regard to the Veteran's claim for headaches as secondary to his service-connected sleep apnea. In the April 2015 Board remand, the examiner was specifically asked to address medical literature that shows a correlation between headaches and sleep apnea. In November 2016, a VA examiner opined that the Veteran's headaches are less likely as not related to his sleep apnea. The examiner reasoned that the Veteran's medical records do not mention "headaches of the proportion/severity related to the current contentions" and concluded that the lack of records, in addition to other medical conditions that could cause the Veteran's headaches, "it would be resorting to complete speculation to state the headaches are specifically due to his sleep apnea, as the rationale is clear." The Board however finds that the November 2016 addendum opinion is inadequate for a number of reasons. The Board notes that the lack of medical records showing complaints of headaches is not an absolute bar to the claim. Second, the examiner did not provide discussion of the medical treatise article submitted, as requested. Moreover, the Veteran has since submitted more articles. See August 2017 Appellant's brief. Third, the examiner did not provide any rationale on the question of aggravation, other than stating that there is no true aggravation of headaches by the sleep apnea. For these reasons, additional clarification is needed. Accordingly, the case is REMANDED for the following action: 1. Obtain and associate with the claims file any outstanding VA medical evidence, specifically to include those dated since the most recent supplemental statement of the case. 2. Then, regardless of whether or not additional evidence is received, obtain an additional opinion by an appropriate examiner as to the etiology of claimed headaches. The need for another examination is left to the discretion of the medical professional offering the addendum opinion. The claims file and a copy of this Remand must be made available to the reviewing examiner, and the examiner shall indicate in the addendum report that the claims file was reviewed. Following a review of the claims file, the reviewing examiner is requested to: (a) Provide an opinion as to whether it is at least as likely as not (50 percent or greater) that the Veteran's current headaches are related to his asserted in-service injuries to include being in close proximity to nerve gas. (b) Provide an opinion as to whether it is at least as likely as not (50 percent or greater probability) that the Veteran's current headaches are proximately due to, caused by, OR aggravated (permanently worsened beyond the natural progression) by the Veteran's service-connected sleep apnea. ** The examiner must specifically address the Veteran's lay contentions and the medical literature submitted by the Veteran in March 2016 and August 2017 informal hearing presentations (IHPs). The examiner should provide a complete rationale for the opinion, whether favorable or unfavorable, and cite to specific evidence of the record, as necessary. If the examiner cannot offer an opinion without resort to speculation, he or she should explain why and state what additional evidence, if any, would be required to offer an opinion. 3. After completing any other development that may be warranted, readjudicate the headache claim on appeal. If the benefits sought are not granted, the Veteran and his representative must be furnished a supplemental statement of the case (SSOC) and afforded a reasonable opportunity to respond before the record is returned to the Board for further review. The appellant has the right to submit additional evidence and argument on the matter or matters the Board has remanded. Kutscherousky v. West, 12 Vet. App. 369 (1999). This claim must be afforded expeditious treatment. The law requires that all claims that are remanded by the Board of Veterans' Appeals or by the United States Court of Appeals for Veterans Claims for additional development or other appropriate action must be handled in an expeditious manner. See 38 U.S.C.A. §§ 5109B, 7112 (West 2014). ______________________________________________ S. B. MAYS Veterans Law Judge, Board of Veterans' Appeals Department of Veterans Affairs