Rads can play key role in diagnosis of anorexia, bulimia

Eating disorders can result in a spectrum of morbidity, or even death, and imaging can play a role in diagnosing these potentially treatable illnesses, according to an article published in the April issue of the American Journal of Roentgenology.

Anorexia and bulimia affect approximately five million Americans each year, but this rate could be an underestimate because these disorders may not readily come to clinical attention, according to Jessica J. Kraeft, MD, of Mount Auburn Hospital in Cambridge, Mass., and colleagues.

“Often, because of embarrassment or social stigma, patients do not readily admit to these disorders when interviewed by caregivers,” they wrote. “Imaging findings can suggest the presence of an eating disorder; understanding these findings allows the radiologist to contribute to the diagnosis of these insidious conditions and alert the referring caregiver.”        

MRI, PET and SPECT can be used to evaluate eating disorders, and Kraeft and colleagues outlined related imaging findings in a number of organ systems:

Neurologic: Neuroimaging findings in patients with anorexia include ventriculomegaly and cerebral spinal fluid space enlargement on MRI and CT, as well as cerebellar atrophy, according to the authors. These can be partially reversed with weight gain. Findings in bulimia are similar to those in anorexia, but less severe.

Cardiopulmonary: Aspiration of regurgitated material is possible in patients with purging subtypes of an eating disorder, explained Kraeft and colleagues. They also noted that in many chronically malnourished patients, the left ventricular mass and cavity size can be decreased and the heart may look small on radiographs, MRI or CT.

Gastrointestinal: A variety of gastrointestinal complications are associated with eating disorders. “Disturbances in gastrointestinal function in eating disorders can cause patients to present with abdominal pain and are thought to play a role in perpetuating the behavioral characteristics of these syndromes,” wrote the authors. “Delayed gastric emptying and constipation can cause symptoms such as bloating, abdominal distentio, and fullness, contributing to early satiety or ‘feeling fat’ in anorexic patients.”

Gastric emptying can be evaluated by scintigraphy, while radiographs and CT can reveal distended stomachs.

Musculoskeletal: Up to half of patient with anorexia suffer from osteoporosis, despite the fact that adolescence—when anorexia often occurs—is the age of peak bone mass. The authors noted that dual-energy x-ray absorptiometery and flat-panel volume CT can indicate sub-optimal bone strength.

In summing up the importance of understanding the imaging findings related to eating disorders, the author wrote that this “knowledge empowers the radiologist to suggest the presence of an occult underlying eating disorder, or, in patients known to be eating disordered, to recognize their complications. In addition, early recognition may prevent future morbidity and mortality in these patients.”