Brain Pathology Case of the Month - July 2002

Contributed by Xuemo Fan, MD, PhD, Terry M Semchyshyn, MD, Louise A Mawn, D., James B Atkinson, MD, PhD, James C Anderson, MD, Steven A Toms, MD, MPH and Mahlon D Johnson, MD, PhD
  Department of Pathology (JBA), Division of Neuropathology (XF, MDJ,), Department of Radiology (JCA), Ophthalmology (TMS, LAM) and Neurosurgery (SAT), Vanderbilt University Medical Center, Nashville, TN 37232, U.S.A.
Published on line in July 2002


CLINICAL HISTORY:

This 66-year-old Caucasian female presented with gradually increasing protrusion of her left eye over a one-year period. She complained of increased tearing and foreign body sensation. She denied any change in vision, pain with eye movement, double vision, headache, or weight loss. Her past medical history was significant for hypertension, hypercholesterolemia, benign breast lump removal, and skin nodule removal. She had no previous eye surgery or trauma. Her family history was negative for malignancy or endocrine disorders. She neither drinks nor smokes.

The physical examination revealed a visual acuity of 20/20 both eyes, full color vision, full visual fields, with motility examination of the left eye restricted in lateral gaze. Pupils were round, symmetric, with no afferent pupillary defect noted. On external examination, her left eye was grossly proptotic with resistance to retropulsion. The left eye showed 4 mm proptosis. Lid fissure measured 12 mm right eye, 16 mm left eye. Slit lamp examination detected conjunctival injection of her left eye. Dilated fundus examination showed normal optic discs with no evidence of disc edema. No lymphadenopathy was detected.

IMAGING:

T1-weighted magnetic resonance imaging revealed a mass that measured 3.7x2.8x2.4 cm centered at the floor of the orbit. The margins of the mass were sharp and the mass showed heterogeneous enhancement. The mass appeared to surround the lateral rectus muscle (arrows, Fig. 1A). There were expansile and erosive changes in both the lateral orbital wall and orbital floor (Fig. 1B). The mass extended both intra- and extraconally and deviated the optic nerve superonasally without optic nerve involvement (Fig. 1C). Computed tomography with contrast revealed similar changes. No evidence of calcification within the mass was noted.

GROSS AND MICROSCOPIC DESCRIPTIONS:

FINAL DIAGNOSIS


International Society of Neuropathology