The employer and insurer appeal from the compensation judge's awards of payment of various medical expenses related to treatment for the employee’s headaches and wrist injuries. We affirm.

On December 7, 2004, Jerry Moore [the employee] sustained a broken rib, three lost teeth, a right eye injury, a right ear laceration, a broken nose, a left wrist fracture, and a right wrist sprain/strain when he was involved in a motor vehicle accident in Virginia in the course of his work as an over-the-road trucker with Q Carriers, Inc. [the employer], a Minnesota employer.  Immediately following the accident, the employee was taken to the emergency room at a local county hospital, where he received casting of his broken wrist and other basic treatment and was released into the care of his wife, with whom he returned to their home in Burlington, North Carolina.  The employee’s injuries continued to give him pain, and on December 9, 2004, his wife took him for further treatment at the emergency room at Alamance Regional Medical Center [Alamance] in Burlington.  In the weeks that followed, the employee continued to receive treatment for his injuries primarily from plastic surgeon Dr. J. Madison Clark, for crushed bones in his face, and from orthopedist Dr. Howard Miller, for his rib and wrist injuries.  On December 27, 2004, Dr. Clark recommended reconstructive surgery, emphasizing that he would not be giving the employee more than typical pain medication, noting, “He does have somewhat of an addictive personality.”

Since the date of the employee’s injury, the employee’s medical treatment for arguably related issues has been frequent and complex.  On January 8, 2005, the employee returned to the emergency room at Alamance, complaining of neck pain and chiefly of uncontrollable “headache for 3 days.”  The emergency room records for that date report that, since his motor vehicle accident on December 7, 2004, the employee had “[s]tarted [with] a [headache] on & off times 2 weeks,” which had grown “worse last 2 days.”  An x-ray of the employee’s neck was normal, and a CT scan of his head and brain revealed “[n]o skull fracture or subgaleal hematoma.”  The employee was diagnosed with a “nonspecific headache” and informed that examination had revealed that the headache “does not have any specific cause.”  He was prescribed medication and given the name and phone number of a neurosurgeon to call for an early appointment and an MRI of his neck.

On January 12, 2005, the employee returned to see Dr. Miller, complaining of continuing pain in his neck and left wrist and numbness in his right wrist.  X-rays of the fractured left wrist and ribs revealed healing, and Dr. Miller prescribed medication and physical therapy.  The intake physical therapy evaluation form on January 19, 2005, documents in part, in addition to specific neck and wrist pain and numbness, that the employee was scheduled to see a neurologist for headaches.  On February 8, 2005, Dr. Miller noted that the employee was “still having a lot of problems with his left wrist,” and he restricted him from working until March 23, 2005.

On February 22, 2005, the employee was examined by neurologist Dr. Clark Pinyan at Johnson Neurological Clinic, in Asheboro, North Carolina.  In his report on that date to Dr. Miller, Dr. Pinyan recounted the employee’s history immediately following his December 7, 2004, work accident as follows:

On March 4, 2005, the employee was seen again at the Alamance emergency room, complaining of headache with photosensitivity but no nausea or vomiting.  He was again diagnosed with a “nonspecific headache” and advised that his headache “does not have any specific cause.”  He was given an injection for his pain, was prescribed additional medication, and was instructed to complete his MRI scans.

On March 8, 2005, the employee underwent the MRI scan of his brain, which was read to reveal findings consistent with inflammation of the “maxillary, ethmoid, and right frontal sinus cells.”  When the employee saw Dr. Pinyan again on March 17, 2005, the doctor reported that the employee had been sleeping a little better with new medications but that he “still has to get up in the middle of the night because of his headache” and that “[h]e has been to the emergency department again because of his headache and got a narcotic injection, which did not help.”  Dr. Pinyan reported that payment for the MRIs of the employee’s head and neck that he had ordered had been denied by the insurer.  He indicated that the employee had brought in his CT scan of his head and x-rays of his neck from the emergency department evaluation, that both had been normal, but that “[t[hese studies are not adequate to show brain or spinal cord pathology.”  He acknowledged that the employee “did get a MRI of the head at the emergency department and this is normal,” adding, “If the MRI of the cervical spine is negative, I think nerve conduction studies of his hands would be appropriate.”  On these conclusions Dr. Pinyan diagnosed “[p]osttraumatic headaches,” noting that “[t]hese may be cervicogenic or migrainous.  I don’t think we have gotten a good assessment of [the employee’s] neck.”  On March 28, 2005, the employee underwent the MRI scan of his neck, which was read to reveal annular bulges at C5-6 and C6-7, without gross evidence of nerve root compression or compromise.  On April 5, 2005, he returned to see Dr. Pinyan, who diagnosed “[p]ost traumatic headaches” “mostly migrainous,” together with “[b]ilateral hand tingling which may be related to carpal tunnel syndrome” and which the doctor related to the work injury “[b]ased on [the employee’s] wrist fractures.”  Dr. Pinyan increased the employee’s medication and indicated, “We will check bilateral nerve conduction studies on [the employee’s] hands.”

The following day, on April 6, 2005, the employee was seen again in the Alamance emergency room, for what was again diagnosed as “nonspecific headache,” and he was thereafter discharged in stable condition into the company of his wife.  Three days later, on April 9, 2005, he was seen again on an emergency basis for his headaches, this time at the Randolph Hospital in Ashboro, North Carolina, where the attending physician, Dr. Donald Hill, reported “a past medical history significant for migraines ever since a motor vehicle collision” on December 7, 2004.  In his systems review, Dr. Hill noted in part that the employee did have some photophobia but no neck pain and no vomiting.  Having noted also that the employee “has had an MRI of the brain, which was negative,” Dr. Hill diagnosed acute headache and ordered a CT scan of the head, which was read to be essentially normal.

A nerve conduction study of the employee’s arms conducted on April 21, 2005, was read to be within normal limits, with no evidence of carpal tunnel syndrome, but Dr. Pinyan noted on that date that there was “sometimes poor correlation between carpal tunnel symptoms and nerve conduction studies” and that, “[g]iven [the employee’s] history of wrist fractures, I think carpal tunnel syndrome is still a possibility despite negative tests.”  When he saw the employee again on April 26, 2005, Dr. Pinyan reported that the employee was sleeping better but that he had not had any improvement in his headaches and had “severe headache today with nausea and vomiting.”  Dr. Pinyan diagnosed continuing “mostly migrainous” posttraumatic headaches and bilateral hand tingling, which he concluded “still may be very mild carpal tunnel,” though there was no evidence of permanent nerve damage on tests.  The doctor went on to prescribe a new medication that he indicated would relieve not only the employee’s migrainous pain but perhaps even the tingling in his hands, concluding that, if current therapies were not effective, botox injections might be an option.

On April 25, 2005, the employee had returned to see Dr. Clark “for follow up of his nasal obstruction,” which the doctor noted had been “continuing to cause significant problems.”  Dr. Clark prescribed medication and again recommended surgery, which the employee opted to proceed with, and on April 28, 2005, Dr. Clark performed reconstructive surgery on the employee’s nose.

Numbness and tingling continued in both of the employee’s hands, and on May 20, 2005, Dr. Miller noted that the employee demonstrated a “markedly positive median nerve compression and Phalen test bilaterally.”  With his clinical examination also otherwise consistent with carpal tunnel syndrome, Dr. Miller injected both of the employee’s carpal tunnels with Xylocaine and Celestone and prescribed carpal tunnel braces and Lodine.  Notwithstanding his carpal tunnel findings and treatment, Dr. Miller released the employee to return to truck driving on May 23, 2005, restricted to lifting no more than twenty pounds, noting also that the employee was “still bothered by headaches.”

On June 2, 2005, Dr. Pinyan wrote to the insurer, indicating that, “[a]lthough I feel like [the employee’s] other neurological symptoms are adequate for him to return to work, I am not sure about his headaches,” noting that he did not think that the employee was ready to return to work as a driver, “due to his severe light sensitivity.”  Apparently in response to a query by the insurer as to the possibility that the employee’s headache condition may have preexisted his 2004 work injury, Dr. Pinyan stated,

On July 7, 2005, the employee returned to Dr. Miller, still complaining of numbness in both hands and “out of work because of his headaches and medication he is taking for this.”   Nerve compression, Phalen’s, and pinch tests were again positive for bilateral carpal tunnel syndrome, which Dr. Miller diagnosed as being “post-traumatic from the twisting and strain effect of the steering wheel at the time of injury.”  Dr. Miller injected both carpal tunnels again, prescribed medication and new wrist splints, and continued the employee’s wrist-related work restrictions.  Dr. Miller also anticipated the need for repeat nerve conduction studies, noting that, “[e]ven if they are normal [the employee] may require surgery.”

On July 8, 2005, the employee’s North Carolina medical case manager, Patricia Royster, reported that, since his last visit to Dr. Pinyan, the employee had reported having had a “blackout” for a few minutes and had had only two days improvement in hand pain following his injections.  Ms. Royster reported that Dr. Miller had found the employee to have “classic bilateral carpal tunnel syndrome,” that the doctor had found the employee’s relief by injection, although only temporary, to have been diagnostic of that condition, and that he had explained that the only other explanation for the employee’s symptoms would be a cervical injury, which had been ruled out by MRI examination.

On July 11, 2005, evidently upon prescription of Dr. Pinyan, a nurse came out to the employee’s home and administered an IV injection of Solumedrol and Valproate in treatment of the employee’s headaches.  About three or four hours after the injection, the employee began to feel symptoms of an accelerated heartbeat, dry mouth, profuse sweating, nausea, chest pain, and headache.  The employee’s wife took the employee to the emergency room at Alamance, where he was admitted into the hospital overnight for a cardiac workup and blood tests.  The cardiac workup evidently revealed no real heart problems, but the blood tests revealed elevated sugars, and the employee was prescribed medication for their reduction, including apparently two follow-up prescriptions of Amaryl.  On July 13, 2005, the employee was administered a pneumonia vaccine and discharged with a sleep study appointment for apnea symptoms that had been observed during his hospitalization.

On July 28, 2005, Ms. Royster wrote to the insurer, indicating that Dr. Pinyan was now recommending botox treatment for the employee’s headaches, that the employee was “still having ‘blackouts’,” and that, “[s]ince [the employee] has had a full cardiology work-up, Dr. Pinyan wants to proceed with the EEG that was previously ordered.”  Ms. Royster indicated that the doctor was keeping the employee off work because of his sensitivity to light and had “agreed [that] the SoluMedrol could increase blood sugar to up to 500 in some people.”  She added that Dr. Pinyan had also strongly suggested that the employee complete the recommended sleep study, opining that the employee’s sleep apnea could be contributing to his headaches, although the doctor had agreed that the apnea “was not related to the [work] injury, unless there is some problem with [the employee’s] nasal reconstruction.”  In a follow-up report on July 29, 2005, the employee’s QRC, Pam Huber, noted that the employee had “had an IV infusion earlier in the day on the 11th” but that it was “unknown if the later episode with chest pain was related.  He had complained of blackouts for several weeks prior.”

When the employee’s wrist symptoms still had not resolved by August 18, 2005, Dr. Miller scheduled bilateral carpal tunnel surgery for August 29, 2005.  Subsequently, the insurer refused to authorize the surgery and, apparently in October of 2005, instructed Ms. Royster to suspend her activities on behalf of the employee, in that no additional medical treatment would be authorized for the employee pending an independent medical examination in Minnesota.  On November 8, 2005, the employee filed a medical request, alleging entitlement to payment or reimbursement of various medical and related out-of-pocket expenses consequent to his December 7, 2004, work injuries.

On March 30, 2006, the employee was examined for the employer and insurer with regard to his headaches by neurologist Dr. Joel Gedan, to whom the employee reported a history of generally twice-weekly headaches since his work injury on December 7, 2004.  Dr. Gedan reported the employee to have stated that “following the accident of December 7, 2004, he developed headaches” and that “approximately one month after the accident in January 2005 he had severe headache.”  He reported the employee also to have recounted that his headaches typically lasted two or three days each, that they typically reached a pain level of eight on a scale of one to ten, that they were typically accompanied by nausea and sensitivity to light, and that they were sometimes accompanied by visual blurring.  The doctor indicated that the employee also reported having had several blackouts and losses of consciousness in the two-month period subsequent to his intravenous medication for headaches in June 2005.  Upon review of the employee’s medical records and physical examination of the employee himself, Dr. Gedan concluded that there were no objective findings to support the employee’s complaints of severe migraine headaches, that the medical records in general did not support a diagnosis of posttraumatic headaches, and that the employee’s presentation was not consistent with such a diagnosis.  In principal support of this conclusion, the doctor stated,

On March 30, 2006, the employee was examined for the employer and insurer also by orthopedic surgeon Dr. Nolan Segal, primarily with regard to the employee’s upper extremity problems.  In his report on May 8, 2006, Dr. Segal related in part that the employee “states that he did sustain loss of consciousness” in his December 2004 work-injury accident and “states that he still has migraine headaches.”  Dr. Segal concluded, however, that the employee had “considerable subjective complaints, which are not substantiated by objective examination findings,” that he had “nonphysiologic responses to examination maneuvers,” and that, although he did have evidence of some mild multi-level cervical degenerative disc disease, “[t]his was noted back in 2002.”  With regard to the employee’s bilateral wrist condition, Dr. Segal indicated that he could not “find any organic basis for [the employee’s] extensive pain, guarding, and subjective complaints.”  He concluded that, “[f]rom a musculoskeletal standpoint, [the employee’s] subjective complaints are due to functional overlay and there may well be an element of secondary gain involved.”  It was Dr. Segal’s further opinion that the employee had reached maximum medical improvement [MMI] from the effects of his December 2004 work injury, without any permanent partial disability, by February 28, 2005, two months after his wrist fracture.  The doctor concluded also that the employee did not require any additional medical care or treatment relative to his work injury and that, from a musculoskeletal standpoint, he did not require any work restrictions and was fully capable of returning to his driving occupation.  Dr. Segal indicated that he found “no evidence, based on [the employee’s] normal EMG and his negative physical examination findings, that he requires carpal tunnel release surgery,” in that even his “nonphysiologic subjective complaints . . . do not fit with carpal tunnel syndrome.”  In conclusion, Dr. Segal found it “interesting to note as well that in 2002 [the employee] complained of numbness and tingling in his entire right hand with no objective neurologic deficits and a normal EMG,” noting, “[a]gain, this does raise a question as to the possibility of secondary gain issues.”

On May 26, 2006, the employee returned once again to see Dr. Miller, who found clinical tests again consistent with carpal tunnel syndrome.  On those findings, as reported to the employee’s attorney on June 19, 2006, Dr. Miller recommended a repeat EMG, “to establish the diagnosis once and for all if it is present,” “since it has been more than one year since his previous study.”  “If the test remains normal,” he concluded, “then surgery would not be indicated.  If positive, then carpal tunnel release would be indicated.”

The matter came on for hearing on June 23, 2006.  According to Stipulation 3 of the compensation judge’s eventual findings and order, the parties agreed at hearing that “[a]ll medical treatment with the exception of the two MRI’s in April of 2005 and June of 2005 [sic],^[2] is treatment which is reasonable and necessary for the condition treated.”  Notwithstanding this stipulation, issues identified in that findings and order for resolution by the compensation judge included the following:  (1) whether the employee’s treatment for migraine headaches on April 9, 2005, with Randolph Hospital, Asheboro Emergency Physicians, and Randolph Radiological Association, on June 21, 2005, with Moses Cone Health System, Greensboro Radiology, and Guilford Emergency Physicians, and on unspecified dates with Johnson Neurological Clinic was reasonable, necessary, and causally related to the employee’s work injury of December 7, 2004;^[3] (2) whether the employee’s “[CT] scans on April 9 and June 21, 2005,”^[4] were reasonable, necessary, and causally related to the employee’s work injury; (3) whether hospitalization, medical, and other expenses related to the employee’s treatment for heart-related symptoms on July 12, 2005, with Alamance Regional Medical Center, Callwood Cardiological Care, and Burlington Radiological Associates, including prescriptions for Amaryl on July 23 and August 15, 2005, were reasonable, necessary, and causally related to the employee’s work injury; and (4) whether the repeat EMG currently being proposed by Dr. Miller for help in diagnosing the employee’s bilateral wrist condition is reasonable, necessary, and causally related to the employee’s work injury.

Evidence introduced at hearing by the employer and insurer included an October 14, 1996, Alamance intake form, preparatory to the employee’s treatment for a gastric disturbance, on which the employee declared a history of recurrent headaches at the front and back of his head once or twice a week.  Also submitted into evidence was a record of the employee being admitted to Alamance on an urgent basis about five years later, on the afternoon of July 8, 2001, with complaints of severe headache and swelling in the back of his head for the past half day.  That record indicates that later that night the employee refused a spinal tap that was recommended to rule out bleeding or infection in his head and that he was thereupon discharged against medical advice.  Evidence introduced by the employer and insurer also included an electrodiagnostic evaluation by Dr. Devlese Howard dated March 21, 2002, a consultation report by Dr. Oliver Dold dated March 22, 2002, and an IME report by Dr. Stephen Pineda dated July 23, 2002, all apparently pursuant to an earlier claim for benefits based on a work injury to the employee’s neck and right shoulder and arm.  Dr. Howard’s evaluation was essentially normal, as was that of Dr. Dold, who reported also the appearance of some symptom magnification, and Dr. Pineda’s report, in addition to limited shoulder findings, referenced a previous head injury, a cervical osteophyte and disc condition, a pulsating, nonanatomic weakness in the right arm, and evidence of symptom magnification.  Finally, also introduced into evidence by the employer and insurer was a record of the employee being treated at the Alamance emergency room in October of 2002, for dizziness, headache, nausea, and burning down the back of his neck following his involvement in a motor vehicle accident; an x-ray of the employee’s neck and a CT scan of his head on that date had been normal.

Evidence introduced at hearing by the employee included testimony by the employee to the effect that pollen-induced headaches that he had experienced prior to his work injury were very different from his post-work-injury headaches, in that the latter “makes you real sick and you can’t stand light or anything.”  Finally, evidence considered by the compensation judge also included a supplementary report from Dr. Segal dated July 17, 2006, and received into evidence post hearing, in which Dr. Segal opined and reiterated in part as follows:

By findings and order filed August 17, 2006, the compensation judge concluded that all treatment at issue was reasonable, necessary, and causally related to the employee’s work injury, and she ordered the employer and insurer to pay for that treatment.  The employer and insurer appeal.

In reviewing cases on appeal, the Workers’ Compensation Court of Appeals must determine whether “the findings of fact and order [are] clearly erroneous and unsupported by substantial evidence in view of the entire record as submitted.”  Minn. Stat. § 176.421, subd. 1 (1992).  Substantial evidence supports the findings if, in the context of the entire record, “they are supported by evidence that a reasonable mind might accept as adequate.”  Hengemuhle v. Long Prairie Jaycees, 358 N.W.2d 54, 59, 37 W.C.D. 235, 239 (Minn. 1984).  Where evidence conflicts or more than one inference may reasonably be drawn from the evidence, the findings are to be affirmed.  Id. at 60, 37 W.C.D. at 240.  Similarly, “[f]actfindings are clearly erroneous only if the reviewing court on the entire evidence is left with a definite and firm conviction that a mistake has been committed.”  Northern States Power Co. v. Lyon Food Prods., Inc., 304 Minn. 196, 201, 229 N.W.2d 521, 524 (1975).  Findings of fact should not be disturbed, even though the reviewing court might disagree with them, “unless they are clearly erroneous in the sense that they are manifestly contrary to the weight of the evidence or not reasonably supported by the evidence as a whole.”  Id.

The employer and insurer have appealed from the compensation judge’s awards (1) of payment for the employee’s multiple emergency room visits related to his headaches, (2) of payment for the employee’s treatment for apparently heart-related symptoms in July of 2005, and (3) of payment for the repeat EMG study being recommended by Dr. Miller.  At Stipulation 3 in her findings and order, the compensation judge indicated that the parties had agreed that “[a]ll medical treatment with the exception of the two [CT scans] in April of 2005 and June of 2005, is treatment which is reasonable and necessary for the condition treated.”  Notwithstanding this assertion, the judge also indicated, in all five of the issues that she enumerated for resolution, that, in addition to its causal relationship to the work injury, the reasonableness and necessity of essentially all disputed treatment remained at issue.  A thorough review of the parties’ briefs, of the hearing transcript, and of the remainder of the judge’s findings and order and copious memorandum leads us to conclude that not only the causation but also the reasonableness and necessity of all disputed treatment was, indeed, at issue, notwithstanding the assertion in Stipulation 3.

The compensation judge awarded payment for over half a dozen emergency room visits by the employee for headache-related symptoms between January and June 2005.  The judge’s award was evidently based in part on a conclusion that the employee “briefly lost consciousness” at the time of his December 7, 2004, work accident, a conclusion in turn based on the employee’s credited testimony that he remembered nothing immediately after the accident prior to a highway patrolman’s extracting him from his vehicle.  The employer and insurer contend that “[s]ubstantial evidence does not support the need for multiple emergency room visits to treat alleged post-traumatic migraine headaches in light of the lack of objective clinical findings to support the existence of this condition.”  They argue that the judge “failed to acknowledge the evidence of pre-existing headache complaints,” that she “ignores the multiple references to lack of objective findings to support the Employee’s complaints of posttraumatic Migraine headaches,” and that her decision was “not based upon a ‘choice’ between conflicting medical experts, but instead based upon her own ‘medical’ findings” of a loss of consciousness following the accident.  We are not persuaded.

On January 8, 2005, about a month after the employee’s work injury, emergency room records at Alamance report that the employee had been having intermittent headaches for about two weeks that had become continuous for the past three days and worse over the past two.  The headaches were mentioned by the employee’s physical therapist on January 19, 2005, to whom the employee had been referred by Dr. Miller for his upper extremity problems, and about a month later, on February 22, 2005, the employee saw Dr. Pinyan specifically about his headache problem.  Dr. Pinyan recounted a history of pain in the back of the employee’s head developing immediately after the work injury - - “later that night” - - till the headache pain was now the employee’s principal problem.  Moreover, the employee’s current pain on the date of Dr. Pinyan’s examination was described as “pounding” and “accompanied by severe sound and light sensitivity as well as nausea and vomiting” and occasional “wavy lines in his right eye,” all apparently referenced as symptomatic of migraine-type headache.  A few weeks later, on April 9, 2005, Dr. Donald Hill, at the Randolph Hospital emergency room, reported a medical history “significant for migraines ever since” the employee’s work injury, noting on that particular date some photophobia though no vomiting.  About two weeks thereafter, when he saw the employee on April 26, 2005, Dr. Pinyan noted that the employee was experiencing both nausea and vomiting concurrent with severe headache. It is true that Dr. Gedan, on March 30, 2006, found no objective clinical findings to support the employee’s claims of the nausea and sensitivity to light that the employee reported to typically accompany his headaches, but Dr. Gedan does not indicate what tests he might have conducted to rule out the credibility of such reports.  In this context, we cannot conclude that Dr. Pinyan was not entitled, in his medical expertise, to credit the employee’s reports of those symptoms as clinical findings or that the compensation judge was not in turn entitled to credit the opinion of Dr. Pinyan.

It is true that, notwithstanding the copious detail of her decision and memorandum, the compensation judge did not mention any of the submitted medical evidence of the employee’s treatment for headache prior to his work injury - - notably the Alamance record of the employee’s report of recurrent headaches in October 1996, the emergency room record of his treatment for headache in July 2001, and the record of his treatment for headache and other symptoms following his motor vehicle accident in October 2002.  The judge did note in her memorandum, however, that “Dr. Piny[a]n specifically reviewed earlier medical records and did not find evidence which would suggest pre-existing causes for the migraine headaches.”  The judge’s reference is apparently to Dr. Pinyan’s June 2, 2005, report to the insurer, in which the doctor referenced having reviewed “exhaustive chart notes” in which notes the doctor saw no evidence of a preexisting migraine condition.  We conclude that that conclusion by the doctor was not unreasonable, nor was it unreasonable for the compensation judge to rely on that expert conclusion.  This latter is particularly true in that Dr. Gedan’s contrary opinion appears to have been premised importantly on a presumption that the employee did not experience any post-injury headache symptoms for nearly a month after his work injury instead of within the two weeks that Dr. Gedan suggested was most typical - - a premise dispelled by the January 8, 2005, Alamance emergency room record to the effect that the employee’s symptoms as of that date had been continuing already for about two weeks.  See Nord v. City of Cook, 360 N.W.2d 337, 342-43, 37 W.C.D. 364, 372-73 (Minn. 1985) (a trier of fact's choice between experts whose testimony conflicts is usually upheld unless the facts assumed by the expert in rendering his opinion are not supported by the evidence).  Nor, we conclude, was it improperly “medical” for the compensation judge to infer from all of the evidence presented that the employee temporarily lost consciousness at the time of his injury, prior to being extracted from his wrecked vehicle.

Because it was based on properly founded expert medical opinion, and because it was not otherwise unreasonable, we affirm the compensation judge’s award of payment for the emergency treatment at issue pertaining to the employee’s migraine headache symptoms.  See Hengemuhle, 358 N.W.2d at 59, 37 W.C.D. at 239.

The compensation judge awarded payment for the employee’s treatment for heart-related symptoms between July 11 and July 13, 2005, immediately subsequent to the employee’s IV treatment at home for headache symptoms under prescription of Dr. Pinyan.  The employer and insurer contend that substantial evidence does not support the judge’s award.  They argue that there is no expert medical opinion linking the employee’s work injury to his cardiac work-up for chest pain at the time and that the employee’s own association of his onset of symptoms with his receipt of the IV infusion does not constitute substantial evidence supportive of such a medical conclusion. We are not persuaded.

While there may be no formal medical opinion linking the employee’s cardiac work-up to his work injury, Dr. Pinyan did suggest to Case Manager Royster that the spike in the employee’s blood sugars may have been a side-effect of the Solumedrol that the employee had been administered intravenously for his headaches just prior to his admission to the hospital for heart-related and high blood sugar symptoms on July 11, 2005.  It would not have been unreasonable for the compensation judge to conclude that the heart and blood sugar-work-ups were collateral treatments directly consequent to the employee’s intravenous medication for his headaches. On that basis we affirm the judge’s award of payment for those treatments from July 11 through July 13, 2005, and for subsequent related medication.  See Hengemuhle, 358 N.W.2d at 59, 37 W.C.D. at 239.

The compensation judge ordered the employer and insurer to pay for the upper extremities EMG currently being recommended by Dr. Miller.  The employer and insurer contend that substantial evidence does not support the need for this additional diagnostic study.  They argue that “[t]he Employee not only had a pre-existing history of complaints similar to his current complaints, he also had, post-accident, an EMG study that was reported as being normal,” evidently in reference to the employee’s nerve conduction study on April 21, 2005.  They argue primarily in reliance on the opinions of Dr. Segal, who, they assert, reached negative findings on Phalen’s, Tinel’s, and compression tests for carpal tunnel syndrome and found the employee to have “exhibited give way weakness, evidence of pain behaviors, symptom magnification, and nonphysiologic responses.”  Dr. Segal also, they assert, “reported as to causation, that any ‘new’ EMG findings, 18 months post-injury, with a negative EMG four months post-injury, would not be related to the December 7, 2004 injury.”  They contend that the only basis identified by the judge for her award of a repeat EMG was “ongoing pain and symptomatology” and that the judge “does not site to any objective clinical findings, even though these are available, and well documented.”  We are not persuaded.

While it is true that the judge herself does not site any objective clinical finding to support her decision on this issue, she clearly references several times her reliance on the opinion of Dr. Miller in this regard.  On May 20, 2005, Dr. Miller expressly found the employee to demonstrate a “markedly positive median nerve compression and Phalen test bilaterally,” and his clinical examination was also otherwise consistent with carpal tunnel syndrome.  Six weeks later, on July 7, 2005, Dr. Miller’s nerve compression, Phalen’s, and pinch tests were again positive for bilateral carpal tunnel syndrome, which the doctor expressly diagnosed as being “post-traumatic from the twisting and strain effect of the steering wheel at the time of injury.”  Notwithstanding Dr. Segal’s examination findings to the contrary, objective clinical findings of a medical expert clearly exist to support the decision of the judge in this case.  Nor are we persuaded by the argument that, upon examination by Dr. Segal, the employee purportedly exhibited evidence of pain behaviors, symptom magnification, and nonphysiologic responses.  These are credibility factors just as available to Dr. Miller and the compensation judge as they were to Dr. Segal, and assessment of a witness's credibility is the unique function of the trier of fact.  Brennan v. Joseph G. Brennan, M.D., 425 N.W.2d 837, 839-40, 41 W.C.D. 79, 82 (Minn. 1988), citing Spillman v. Morey Fish Co., 270 N.W.2d 781, 31 W.C.D. 187 (Minn. 1978).

It is arguable that bilateral carpal tunnel release surgery might have been warranted already at the time of the April 2005 EMG and might still be warranted without the repeat study currently being recommended, based solely on Dr. Miller’s clinical findings alone.  This is true particularly in light of Dr. Pinyan’s statement at the time of the 2005 study, that there is “sometimes poor correlation between carpal tunnel symptoms and nerve conduction studies” and that, “[g]iven [the employee’s] history of wrist fractures, . . . carpal tunnel syndrome is still a possibility despite negative tests.”  With the employee’s condition little changed since that time, in spite of efforts with other treatment options, we conclude that it is not at all unreasonable for Dr. Miller to look conservatively one more time, before undertaking surgery, to nerve conduction studies for help in confirming “once and for all” a diagnosis that appears to him compelling, resolving, in fact, to base his final decision as to surgery on the results. Nor was it unreasonable for the compensation judge to rely on that reasonable decision of a medical expert.  See Nord, 360 N.W.2d at 342-43, 37 W.C.D. at 372-73.  Because it was not unreasonable, we affirm the compensation judge’s award of payment for the EMG being recommended by Dr. Miller.  See Hengemuhle, 358 N.W.2d at 59, 37 W.C.D. at 239.