Sunday, June 07, 2009

APA - Neuroimaging: A Glimpse Into the Future of Psychiatry

Interesting article from the APA on the future of neuroimaging in psychiatric treatment. It's more of a flatland (objective reality only) approach, but the technology is promising.

Neuroimaging: A Glimpse Into the Future of Psychiatry

May 25, 2009

Horacio A. Capote, MD

Medical Director, Division of Neuropsychiatry at Dent Neurologic Institute; Clinical Assistant Professor, State University of New York, Buffalo School of Medicine

First published in Psychiatry Weekly, Volume 4, Issue 12, on May 25, 2009

This interview was conducted on April 22, 2009 by Lonnie Stoltzfoos

Introduction

In psychiatry, where much of the diagnostic criteria for mental illness are based on phenomenological observation, Dr. Horacio Capote believes that neuroimaging can begin to foster a more objective understanding of the pathophysiology and treatment of many mental disorders.

As Dr. Capote explains, “these illnesses quite often do not bear any physical sequelae, so by delineating changes going on in the brain, it becomes easier to understand the effects these illnesses have on patients’ daily lives, and it becomes easier to explain a disorder to both patients, their families, and the healthcare industry.”

There is a chance that neuroimaging-derived data will shape the classification structure of the DSM-V, although neuroimaging has yielded significant breakthroughs in only several mental illnesses. Currently, our understanding of cognitive disorders and addictive disorders has benefited most from neuroimaging data.

“We are already able to differentiate between Alzheimer’s dementia and frontotemporal dementia with a high degree of accuracy—so much so that it is accepted by insurers and Medicare,” Dr. Capote explains. “Clinically, that’s very helpful to patients because it really does change the long-term management of the disorders; it gives us prospective expectations about the course of the different illnesses and how patients might respond to different medications.”

Dr. Capote notes that mood disorders comorbid with dementia can be ferreted out quite often by imaging results, adding that imaging is already very useful in his daily clinical practice with this particular group of patients.

A great deal of information is amassing on the pathophysiology of addictive disorders, particularly in regard to the question of whether a disorder is more addictive or obsessive compulsive in nature. “Compulsive shopping,” for example, although it is not an official category, appears to be more of an addictive disorder. Functional neuroimaging is showing increased activity in the nucleus accumbens in compulsive shoppers, which is more consistent with an addictive process. This would certainly make a difference in how you treat that patient.

Neuroimaging and Treatment

“Neuroimaging has opened up areas of treatment that, before, we would have only imagined,” says Dr. Capote. “In February 2009, the FDA approved DBS for treatment refractory OCD, which followed approval of rTMS as a second-line treatment for depression, in October 2008. This demonstrates the direct relationship between greater anatomical understanding and successive application of these other treatment modalities, which are opening up a new armamentarium for mental illness.”

Imaging has also contributed to new developments that can sometimes enable clinicians to identify who is most likely to respond to certain medications. For example, evidence from patients studied with functional neuroimaging in adulthood or adolescence could show who would be most likely to respond to SSRI treatment or to ECT.

“Ultimately,” says Dr. Capote, “I think imaging will help us parse out the genotypes and subtypes of patients that currently exist within one classification of the DSM-IV—the varieties of underlying, existing pathophysiology.”

Imaging in Practice

Daily access to imaging technology appears to be confined to a limited number of practices and clinics. With due consideration given to the enormous cost, size, and logistics involved with acquiring imaging equipment, Dr. Capote still hopes that more clinicians will begin to realize the benefits of integrating imaging in daily practice.

“We tell our patients that mental illnesses are brain disorders, so, especially for those with a first-time diagnosis, it would be important for us to see what’s happening in their brains,” he explains. “Even with normal MRI, it is not unusual to find that patients who have developmental disorders may have a lack of connection between hemispheres. I have had the experience of finding young people who have suffered silent strokes as a result of experimentation with different substances, suggesting some treatment resistance and perhaps requiring a special approach to treatment. Also, it’s not unusual to make a variety of surprising discoveries—such as a brain mass—in patients that end up being very useful in long-term management and short-term treatment decisions.”

Technology Advances

Regarding advances in the actual imaging technology, Dr. Capote notes that diffusion tensor imaging, which is of particular value in neurology, is developing nicely. More institutions are upgrading their MRI technology as well, moving to equipment featuring the more detailed 3T magnet, as opposed to the more prevalent 1.5T magnet. With the greater detail of the 3T magnet, Dr. Capote says it might be possible to spot a lesion 1–2 years earlier than with older technology, of course enabling a clinician to corner a diagnosis much sooner. Basic imaging aside, however, Dr. Capote also notes that functional modalities, such as white matter tracts, may be the wave of the future, because they provide a lot of information with comparative ease and less expense.

“To the extent that we embrace all these new modalities and apply them to our patients,” he says, “we will be all the better for it.”


Disclosure: Dr. Capote has served on the speaker’s bureau of Eli Lilly, Forest, GlaxoSmithKline, Novartis, Pfizer, and Wyeth; and has received research/grant funding from GlaxoSmithKline.


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