Can Brain Imaging Aid Diagnosis of Mental Illness?

Fran Lowry

July 20, 2012

July 20, 2012 — Brain single photon emission computed tomography (SPECT) neuroimaging can help psychiatrists make more reliable diagnoses and improve treatment of complex psychiatric cases, new research suggests.

"The SPECT images show a pattern to help you understand where the brain is not functioning properly and teach you to ask better questions," study investigator Daniel G. Amen, MD, founder of Amen Clinics, Newport Beach, California, told Medscape Medical News.

"It helps to refine your treatment and can change the way patients are managed. In fact, we have found that it changes the diagnosis and treatment in nearly 8 out of 10 cases," he added

The case series was published online June 8 in the Journal of Psychoactive Drugs.

In this prospective case series report, the researchers examined the charts of 109 consecutive outpatients (49 female, 60 male) who were seen at 4 psychiatric clinics that use SPECT neuroimaging for complex cases.

Patients ranged in age from 18 to 87 years (mean age, 38.42 years). The average number of diagnoses upon entering the study was 4.2 per patient.

The most common diagnoses were as follows:

  • Anxiety (90.8%; n = 99)

  • Mood disorders (69.7%; n = 76)

  • Substance abuse (64.2%; n = 70)

  • Attention-deficit/hyperactivity disorder (53.2%; n = 58)

  • Head injury (35.7%; n = 39)

  • Obsessive compulsive disorder (15.5%; n = 17)

  • Dementia of any type (10.0%; n = 11)

  • Schizophrenia (3.6%; n = 4)

  • Epilepsy (1.8%; n = 2)

Imaging Data Changed Treatment Course

The charts were analyzed in 2 stages. In the first, psychiatrists reviewed detailed clinical histories, mental status examinations, and the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. The results of the SPECT studies were not included. They then made a diagnosis and developed a treatment plan.

In the second stage, the psychiatrists were given access to the SPECT studies for each patient, in addition to the other information.

The researchers report that the addition of SPECT modified the diagnosis or treatment plan in 86 (78.9%) patients.

Specifically, SPECT imaging completely changed the course of treatment in 57 (52.3%) patients; 29 patients (26.6%) had moderate changes to their treatment; 12 patients (11%) had mild changes to their treatment; and 11 patients (10.1%) had no change in their diagnosis and treatment plan.

The most clinically significant changes were undetected brain trauma (in 22.9% of patients), toxicity patterns (22.9%), and the need for a structural imaging study (9.2%).

Complex Patients

"In our study, the use of SPECT neuroimaging modified the diagnostic thinking and led clinicians to make different, specific treatment recommendations in a high percentage of cases," Dr. Amen said.

Although there is more work to be done to facilitate the widespread use of SPECT neuroimaging and other functional neuroimaging studies in routine clinical practice, "it is important to have a sense of urgency so that we do not miss important information that can offer significant help in the healing process of patients," he added.

According to Dr. Amen, SPECT brain imaging also decreases the stigma of psychiatric illness and increases compliance. Brain scanning in complicated psychiatric patients makes "perfect sense," he said.

"By the time these complicated patients have seen most psychiatrists, they are not simple. Also, 85% of psychiatric medications are being prescribed by nonpsychiatric physicians such as the family doctor, gynecologist, internist, primary care doctor.

"That is a problem all by itself, but by the time these patients actually come to our clinic, on average, they have 4.2 diagnoses and have failed 3 or 4 medications. So our average patient is complicated," Dr. Amen said.

Caution Warranted

Commenting on the study for Medscape Medical News, John Seibyl, MD, president of the Society of Nuclear Medicine and Molecular Imaging's Brain Imaging Council, voiced a note of caution about using SPECT to diagnose psychiatric disorders.

"When interpreted by physicians that are properly trained and credentialed, brain perfusion imaging with single photon emission computed tomography is valuable for a number of neurologic disorders, such as epilepsy, dementia, and brain tumors," said Dr. Seibyl, who is also affiliated with the Institute for Neurodegenerative Disorders in New Haven, Connecticut.

"There is currently no evidence that SPECT can be used in individual patients to diagnose psychiatric disorders, with the exception of dementia," he added.

"Additional, careful scientific investigations around the use of brain perfusion SPECT in therapeutic evaluations are needed before this type of application can benefit patients."

Dr. Amen and Dr. Seibyl have disclosed no relevant financial relationships.

J Psychoactive Drugs. 2012;44:96-106. Published online June 8, 2012. Abstract