Journal of Postgraduate Medicine, Vol. 46, No. 2, April-June, 2000, pp. 94-95

Case Report

An Intragastric Trichobezoar: Computerised Tomographic Appearance

Morris B, Shah ZK, Shah P

Department of Radiology, Seth G. S. Medical College and K. E. M. Hospital, Parel, Mumbai - 400 012, India
Dr. Buz Morris, Department of Radiology, Seth G. S. Medical College and K. E. M. Hospital, Parel, Mumbai 400012. India E-mail: kemrad@vsnl.com

Code Number: jp00025

Abstract:

A 26-year-old lady presented with a history of abdominal pain and distension since two months. The ultrasound examination showed an epigastric mass, which was delineated as a filling defect in the stomach on barium studies. The computerised tomographic scan showed a gastric mass with pockets of air in it, without  post-contrast enhancement. This case highlights the characteristic appearance on computerised tomography of a bezoar within the stomach, a feature that is not commonly described in medical literature. (J Postgrad Med 2000; 46:94-95)

Keywords: Computerised Tomography, Trichobezoar, Stomach, Gastrointestinal tract, Abdominal mass.

The term trichobezoar derives from the Arabic "Bazahr" which means protection from poisoning. A bezoar is an aggregation within the gut of indigestible foreign matter, which is repeatedly ingested over a period of time. They can be broadly classified as ¹ : trichobezoars (hair ball), phytobezoars (food ball) and miscellaneous (pharmacobezoar, seeds of fruits, lactobezoar).

Bezoars most commonly occur in ruminants. Animal bezoars were highly prized as universal remedies and tests were devised by which true bezoars could be distinguished from counterfeits ² .   Bezoars were known since the twelfth century and despite their rarity, they were listed in the London Pharmacopoeias until the mid eighteenth century. The description of the first authentic case of human trichobezoars was in 1779 ² . Though suspected clinically and on ultrasound, they are best identified on barium studies and computerised tomography (CT). Bezoars are commonly found in the stomach though occasionally, trichobezoars can have a tail that extends through the pylorus into the proximal duodenum.

Case Report

A 26-year-old woman presented with an epigastric lump since two years with occasional vague abdominal pain unrelated to meals. Considering the size of the lesion it is surprising that a history of satiety and vomiting after food intake was not elicited. A freely mobile lump in the epigastrium, which was firm and non-tender, raised the possibility of a bezoar.

The ultrasound examination showed an ill-defined epigastric mass comprising of echogenic linear bands with posterior acoustic shadowing. Barium study revealed a large filling defect within the stomach with a mottled pooling of barium along the outer margins of the lesion. The "C" loop of the duodenum appeared normal.

The initial CT scan revealed a well-circumscribed lesion in the region the stomach that comprised of concentric whorls of different densities with pockets of air enmeshed within it. Oral contrast (diluted 60% iodinated contrast) filled the more peripheral interstices of the lesion with a thin band of contrast circumscribing the lesion (Figure 1). Absence of significant post intravenous contrast enhancement precluded a neoplastic lesion. Endoscopy prior to surgery confirmed the imaging findings.

The Bezoar was removed in entirety on gastrotomy and the patient fared well post-operatively. Its configuration suggested a cast of the entire stomach comprising of matted human hair, which was unyielding on pressure.

Discussion

The Bezoar most commonly encountered is the Trichobezoar which is almost exclusively seen in young females, often associated with psychiatric problems. It is postulated that hair strands too slippery to be propulsed are initially retained in the mucosal folds of the stomach and become enmeshed over a period of time. Trichobezoars are usually black from denaturation of protein by acid, glistening from retained mucus and foul smelling from degradation of food residue trapped within it ³ . Phytobezoars are made up of undigested fibres and seeds of fibrous and pulpy fruits. These are more commonly encountered in males and mainly in the small bowel; often with a previous history of gastric surgery ^5.

The patient generally presents with epigastric discomfort, pain, nausea, vomiting and satiety exacerbated at meal times. The more severe manifestations would be complete gastric outlet obstruction. Contiguous extension of a trichobezoar into the small bowel can lead to the "Rapunzel syndrome" ² . Detached fragments of the bezoar may be detected as "satellite masses" within the small bowel and could lead to small bowel obstruction. Trichobezoars with small bowel extensions may produce other complications viz. bleeding, perforation, protein losing enteropathies ¹ , steatorrhoea, pancreatitis, appendicitis and intussusception ⁴ .

  The characteristic appearance on CT is of an inhomogenous non-enhancing mass within the lumen of the stomach/bowel. Oral contrast circumscribes the mass and may fill the interstices near the surface . The lesions within the stomach often reach a large size as the root cause of the problem viz. trichotillomania/trichophagy is often undetected. Minute air pockets giving a mottled appearance to the mass on CT simulate small bowel faeces, a finding described in high-grade small bowel obstruction.

CT best describes the size and configuration of the bezoar and establishes its location convincingly. Further, the highly characteristic CT appearance permits ready differentiation from other pathologies viz. intra- or extra-gastric neoplasms, which would be difficult on plain radiography or on ultrasound.

References