Racemose neurocysticercosis of the basal arachnoid cisterns: illustrative case

Abstract

Background: Neurocysticercosis is a parasitic infection of the central nervous system caused by the helminth Taenia solium. Racemose neurocysticercosis is a rare form of the disease that specifically involves cerebrospinal fluid-filled spaces in the brain and carries a high rate of complications and mortality.

Observations: This report describes the case of a 37-year-old man who developed headaches and nausea, which were found to be secondary to racemose neurocysticercosis. He ultimately required an endoscopic third ventriculostomy, which provided transient symptom relief. In the weeks following the procedure, his symptoms returned, at which point a recommendation to proceed with a ventriculoperitoneal shunt was made.

Lessons: The presentation of racemose neurocysticercosis is wide-ranging and often nonspecific. Patients who respond well to initial surgical management with endoscopic third ventriculostomy can still require more durable measures, such as a ventriculoperitoneal shunt, in the following months. https://thejns.org/doi/10.3171/CASE24489.

Keywords: hydrocephalus; neurocysticercosis; neuroendoscopy; racemose.

FIG. 1.

Coronal (A), axial (B), and sagittal (C) head CT images obtained in the emergency department, showing multiple foci of calcification (arrows) and supratentorial ventriculomegaly with suspected aqueductal stenosis. Sagittal (D) and axial (E) T2 CISS MRI demonstrated heterogeneous material in the prepontine, crural, interpeduncular, and ambient cisterns (arrows). Axial precontrast (F) and postcontrast (G) T1-weighted MRI showed no abnormal contrast enhancement.

FIG. 2.

Intraoperative endoscopic photographs (A–F) obtained during the third ventriculostomy. Multiple cysts are seen protruding through the opening in the floor of the third ventricle after an opening was made. The cysts were carefully removed using endoscopic forceps. h = hypothalamus; m = mammillary body; p = parasitic/racemose cysts; t = tuber cinereum.

FIG. 3.

Histopathological photomicrographs of the racemose cyst material obtained intraoperatively, showing racemose cyst walls (arrow) with multiple layers. There appears to be an outer cuticular (c) layer with a subjacent cellular layer (cl) composed of small, vaguely defined epithelioid cells and an inner reticular layer (r) with loosely arranged fibrils. This inner reticular layer also contains nonspecific inflammatory cells and appears to be moderately edematous. No definite viable organism structures (such as hooklets, scolices, or intact larva) are visible. Hematoxylin and eosin, original magnification ×2 (A) and ×20 (B).

FIG. 4.

Two-week follow-up axial T1-weighted (A) and axial (B) and sagittal (C) T2-weighted MRI revealed improvement of previous supratentorial ventriculomegaly.