The employer and insurer appeal from the compensation judge’s award of medical treatment expenses.  The employee cross-appeals from the compensation judge’s denial of claimed expenses for prescription medication, and from the denial of expenses related to a physician’s visit on August 10, 2006.  We affirm, in part, and reverse, in part.

On November 9, 1987, Lois J. Halverson, the employee, sustained an injury to her neck and upper back while employed as a warehouse worker for the K-Mart Distribution Center.  Her duties included picking up orders for customers, which required driving a forklift and pulling merchandise from high storage racks.  On November 9, 1987, the employee experienced pain in her neck and upper back, along with headaches and pain radiating into her left upper extremity.  At the same time she experienced those symptoms, she was hit in the head with some boxes that fell off overhead racks.

Approximately one week later, the employee sought medical treatment at Park Nicollet Medical Center; she was prescribed physical therapy, which she underwent between late November 1987 and March 1988.  In addition to physical therapy, the employee was prescribed home traction, exercise and medication.  A CT scan taken on December 18, 1987, revealed a herniated disc at the C5-6 level on the left.

The employee was disabled from work as a result of her injury between November 9, 1987, and late January 1989, but for a brief period of part-time employment in November and December 1988.  In April 1988, due to her ongoing symptoms, the employee consulted Dr. Ann Brutlag, a specialist in physical medicine and rehabilitation.  Under the care of Dr. Brutlag, the employee received cortisone shots, participated in intensified physical therapy, wore a collar or head gear device for home traction, and utilized a TENS unit.

The employer and its self-insurance administrator ultimately admitted primary liability for the injury, and paid benefits on behalf of the employee, including wage loss benefits, rehabilitation assistance and medical expenses paid in conjunction with a settlement the parties entered into in December 1988.  As part of that settlement, the employer admitted that the employee had sustained a 9% permanent partial disability to the body as a whole, relative to her cervical spine, and eventually paid impairment compensation based on that rating.

In late January 1989, the employee began working for the employer as a switchboard operator.  The employer paid temporary partial disability benefits to the employee while she worked at this position.  The employee later worked in a receptionist position at a K-Mart warehouse, and continued working there until January 1996, at which time she resigned from her position.

In addition to her post-injury treatment with Dr. Brutlag, the employee also consulted Dr. Lowell Campbell, Psy.D., licensed psychologist.  Dr. Campbell diagnosed a major depressive disorder and chronic pain disorder, and has continued to treat the employee for depression since at least June 1989.   The employer admitted liability for the employee’s depression, through counseling sessions, and initially paid for treatments with Dr. Campbell.

On November 8, 1989, an evidentiary hearing was held on this matter, to address the issues of whether the employee had reached maximum medical improvement from the effects of her November 9, 1987, work-related injury, and whether she was working at a suitable job within the meaning of Minn. Stat. § 176.101, subd. 3e (in effect at the time of injury, repealed 1995).  In his Findings and Order served and filed February 6, 1990, Compensation Judge Schultz concluded that the employee had not yet reached maximum medical improvement from the effects of her personal injury, in part because she had not yet been served with any report from her treating psychologist stating that she had reached MMI for that condition.  No appeal was taken from that findings and order.

In 1991, the employee also began treating with William Davis, D.O., a psychiatrist.  Dr. Davis has continued to prescribe psychotropic medication for the employee, as treatment for her depression.  The employee has continued to treat with Dr. Campbell since 1989; he provides her with counseling or therapy sessions.

The employee has undergone two surgeries to her cervical spine.  The first in June 1994 included a cervical discectomy with a fusion at the C4-5 and C5-6 levels.  Following that surgery, the employee continued to work for the employer, until January 1996.  At the time of her resignation in 1996 the employee was receiving intermittent counseling treatment through Dr. Campbell.

In September 1998, the employee underwent a second surgery, in the nature of an anterior cervical discectomy and C6-7 fusion.  Although the employee noted improvement in her neck symptoms for a few months following that surgery, she has experienced neck symptoms since 1999 and has continued to take pain medication for her neck symptoms.

In addition, the employee has received periodic counseling treatment from Dr. Campbell.  One of the disputes presented on appeal is the compensability of the employee’s treatment with Dr. Campbell, specifically, her treatment between 2002 and 2006.  According to the employee’s testimony, these sessions helped relieve her depression and help her to relax.  The employee has undergone relatively limited treatment with Dr. Campbell since 2002, in part because the employee and her husband have resided in Arizona on a part-time basis since 1996 and therefore for a portion of the year the employee has received no treatment from Dr. Campbell.  In 2002, the employee consulted Dr. Campbell nine times, and consulted him once in 2003, eight times in 2004, eight or nine times in 2005, and six times in 2006.

Dr. Campbell has diagnosed the employee as having a “major depressive disorder, in recurrent form and chronic pain disorder.”  By deposition, Dr. Campbell testified that he provides a combination of cognitive behavioral therapy and interpersonal therapy.  He acknowledged that since approximately 1990 the employee has been in what he would consider a “maintenance phase” with respect to her care.  He also acknowledged that the employee has sustained other stresses in her life, including the death of family members, but opined that the effects of her personal injury in 1987 still substantially contribute to her need for psychotherapy.

In addition to her ongoing psychological counseling, the employee has continued to treat with Dr. Brutlag, who has performed trigger-point injections since 2000, at the rate of an average of two or three per year, to treat the employee’s neck pain.  According to Dr. Brutlag’s report of November 22, 2006, she diagnosed the employee as having chronic neck pain, bilateral upper quarter myofascial pain, and bilateral occipital neuralgia.  Dr. Brutlag has recommended pain medication, including ibuprofen, Flexeril and Tylenol #3.

The employee testified that, to varying degrees, she has noticed constant neck pain since at least 2002.  She also testified that when her neck pain increases she develops more headaches, and that her pain can affect her mood in that more severe pain causes her to become more depressed.  In addition to her pain medication, the employee takes Wellbutrin, Zoloft, and Cylert.  Dr. Davis has prescribed Wellbutrin and Zoloft for the employee’s depression symptoms.  Dr. Anthony Spagnola, one of Dr. Brutlag’s colleagues, has prescribed Cylert.  The employee testified that the Cylert helps her to keep awake during the day so that she is able to sleep at night.  She has noticed that her pain medication affects her memory, but her continued symptoms prevent her from permanently reducing the amount of her pain medication.

On November 6, 2006, at the request of the employer and insurer, the employee underwent an independent psychiatric evaluation with Dr. Paul Arbisi, Ph.D., L.P.  In his report of November 10, 2006, Dr. Arbisi diagnosed the employee as having “a major depressive disorder, recurrent moderate.  Pain disorder associated with psychological factors by history.”  Dr. Arbisi found no causal relationship between the employee’s pain complaints and her depression.  He believed that the depression was independent of her pain complaints, and instead was, in part, related to her perception of her limitations restricting her ability to work.

Since 2002, the self-insured employer has denied payment for the employee’s psychotherapy provided by Dr. Campbell.  The employee filed a medical request, seeking payment for psychotherapy she had received from Dr. Campbell between 2002 and 2006, as well as payment for the psychotropic medications prescribed by both Drs. Davis and Spagnola.  She also sought payment for a consultation with Dr. Davis she attended on August 10, 2006.  The employer denied the employee’s medical request, contending that the treatment for which the employee sought payment was not causally related to her 1987 work-related injury.  Following an administrative conference held to address the medical request, the employee filed a request for a formal hearing, which was then held before Compensation Judge Schultz on December 12, 2006.  In his Findings and Order served and filed January 10, 2007, the compensation judge awarded payment for the treatment rendered by Dr. Campbell from 2002 through the hearing date, but denied the employee’s claims for payment for the prescribed medication of Wellbutrin, Zoloft and Cylert, and denied payment for the employee’s August 10, 2006, visit with Dr. Davis.

The employer appeals from the award of medical treatment expenses with Dr. Campbell, and the employee cross-appeals from the denial of payment for prescription medication and for expenses related to the employee’s appointment with Dr. Davis on August 10, 2006.

When an appeal is taken from a compensation judge’s factual findings, this court’s review on appeal is limited to a determination of whether the judge’s findings and order are “clearly erroneous and unsupported by substantial evidence in view of the entire record as submitted.”  Minn. Stat. § 176.421, subd. 1(3).  If, on the other hand, the judge’s factual determinations are adequately supported by substantial evidence, and not clearly erroneous, we must affirm.  Substantial evidence supports the findings if, in the context of the record as a whole, 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 the evidence conflicts or more than once inference may reasonably be drawn from the evidence, the findings must be affirmed.  Id. at 60, 37 W.C.D. at 240.

The compensation judge concluded that Dr. Campbell’s treatment was reasonable and necessary “in the attempt to cure and relieve her from the effects of the November 9, 1987 injury,” and that the injury represented a substantial contributing factor to the employee’s need for that care.  In his memorandum, the compensation judge explained that the employee continues to note the effects of her 1987 injury, and requires treatment to address her symptoms.  That treatment included trigger-point injections and medication prescribed by Dr. Brutlag for pain relief, and counseling treatment provided by Dr. Campbell to address the employee’s depression.

The compensation judge found the employee’s testimony to be credible concerning her ongoing symptoms and the effectiveness of Dr. Campbell’s treatment.  "Assessment of witness credibility is the unique function of the factfinder."  Tews v. Geo. A. Hormel & Co., 430 N.W.2d 178, 180, 41 W.C.D. 410, 412 (Minn. 1988); see also Brennan v. Joseph G. Brennan, M.D., P.A., 425 N.W.2d 837, 839-40, 41 W.C.D. 79, 82 (Minn. 1988).  We defer to the compensation judge’s reliance on the employee’s testimony concerning the continued effectiveness of her treatment.

In addition, the compensation judge addressed opinions of both Dr. Campbell and Dr. Arbisi.  The judge commented in his memorandum that he did not accept Dr. Arbisi’s opinion on the issue of the reasonableness and necessity of Dr. Campbell’s counseling treatment, in part because he found that Dr. Arbisi inaccurately stated some of the history and comments made by the employee.  The judge’s determination concerning Dr. Arbisi’s opinion relates back to his determination of the employee’s credibility, a determination we have already concluded is within the judge’s purview.

The judge instead relied on the opinions of Dr. Campbell.  The employer contends that Dr. Campbell’s opinion on the causation of the employee’s depressive condition lacks foundation, arguing that there was no testimony from Dr. Campbell concerning his knowledge of the employee’s ongoing pain complaints and the medical treatment she has undergone since her work injury, nor concerning whether he had reviewed the employee’s medical records.  The employer also argues that Dr. Campbell’s chart notes do not specifically refer to pain complaints but instead to the employee’s complaints of dealing with the employer on workers’ compensation issues.  In conjunction with this argument, the employer also contends that the psychotherapy is related more to family crises than to dealing with the employee’s pain issues surrounding her work injury.  On these bases, the employer argues that Dr. Campbell’s opinion cannot serve as adequate support for the compensation judge’s conclusions.

We reject the argument that Dr. Campbell was unqualified to render opinions concerning the causal relationship between the employee’s work injury and her need for ongoing psychological counseling.  Dr. Campbell, a licensed psychologist, has treated the employee periodically since at least since 1989.  As a general rule, this level of knowledge is sufficient to afford foundation for the opinion of a medical expert.  Drews v. Kohl’s, 55 W.C.D. 33 (W.C.C.A.  1996).  The decision concerning the weight to be given to evidence submitted at the hearing, and whether to accept or reject an expert's opinion, is for the compensation judge, not this court.  See Nord v. City of Cook, 360 N.W.2d 337, 37 W.C.D. 364 (Minn. 1985).  Here, the compensation judge accepted Dr. Campbell’s opinion.  Because his opinion was adequately founded, the compensation judge could reasonably rely upon that opinion.   On this record we cannot say the compensation judge's decision concerning the compensability of the employee’s psychological counseling was unsupported by substantial evidence.

The employer also contests the compensability of Dr. Campbell’s treatment, because he had no treatment plan, his notes do not definitively describe the type of treatment rendered to the employee during her sessions, and his treatment was not truly providing any long-lasting benefit to the employee as it had been going on since 1990 in a “maintenance” phase.

In his memorandum, the compensation judge acknowledged the arguments presented by the employer, and concluded as follows:

The compensation judge referred to the lack of a treatment plan and also stated that it “appears that he does not provide classic textbook treatment of cognitive behavioral therapy and interpersonal therapy.”  The judge, however, concluded that the claimed treatment, between 2002 and 2006, was reasonable, necessary and causally related to the employee’s 1987 work injury.  Because there is adequate evidence in the record to support that conclusion, we affirm.

The compensation judge denied the employee’s claim for payment of prescription medications prescribed by Dr. Davis and Spagnola for use in conjunction with therapy treatment for the employee’s psychological condition.  The judge denied the medication expenses, even though there is no dispute that such medication is reasonable and necessary, basing his denial of the lack of a specific opinion from Dr. Davis relating his treatment and the medications to the employee’s November 9, 1987 injury.  The employee appeals from that denial and from the related denial of the cost of her office visit with Dr. Davis on August 10, 2006.  She testified that her use of Wellbutrin and Zoloft kept her mood on an “even keel.”  She also testified that her pain medication resulted in daytime sleepiness, and that Dr. Spagnola prescribed Cylert to help her remain alert during the day so that she could sleep at night.

In a report dated August 18, 2005, Dr. Davis outlined his basis for continuing to prescribe Wellbutrin and Zoloft and his opinion that the medication is reasonable.  Dr. Davis explained that the employee originally tried Paxil in 2002 for her increased anxiety, but due to significant side effects was alternatively prescribed Zoloft.  He concluded that the employee had experienced a good response to the combination of Zoloft and Wellbutrin, and recommended continued use of those two medications to treat her depression and anxiety.

Dr. Arbisi concluded that the employee’s depression seemed to have stabilized by 1994.  Even though he did not relate the employee’s psychological and psychiatric treatment to her 1987 work injury, Dr. Arbisi believed that the employee’s psychiatric care between 2001 and 2006 had been reasonable in terms of managing her medication and recommended that she continue on that same medication regimen.

 The employee continues to receive periodic therapy to treat her depression and anxiety, and we have affirmed the compensation judge’s finding that such treatment is causally related to the employee’s 1987 injury.  She continues to use Wellbutrin, Zoloft and Cylert in combination with her psychotherapy.  We acknowledge that Dr. Davis’s report of August 18, 2005, contains no specific statement that this continuing medication is causally related to the employee’s 1987 work injury.  Based on the medical records in evidence, however, including Dr. Arbisi’s and Dr. Davis’s reports and their opinions concerning the efficacy of the psychotropic medication, and based on the employee’s testimony about the benefits of both the medication and the counseling, testimony which the compensation to be credible, we conclude that the record does not support the compensation judge’s denial of the expenses related to that medication.  We therefore reverse the denial of the employee’s claim for reimbursement of expenses related to the medications Wellbutrin, Zoloft and Cylert.  We also reverse the denial of reimbursement for the cost of the employee’s office visit with Dr. Davis on August 10, 2006.