Endocrine Abstracts

Background: Rathke’s cleft cysts (RCC) are benign intrasellar cysts that originate from the remnants of Rathke’s pouch and contain mucoid material. Most are asymptomatic, but some may compress adjacent structures leading to visual disturbances and endocrinopathies.

Case Report: A 20-year-old gentleman had an MRI Head in view of headaches. This showed a 17.7 mm peripherally enhancing suprasellar lesion with no intrinsic T1 high signal pre- contrast. He presented acutely three weeks later with headaches, blurred vision, sudden onset polyuria, polydipsia, and lethargy. An MR Pituitary showed a 23 mm, lobulated, peripherally enhancing sellar/suprasellar mass with elevation of the optic chiasm. The right optic tract showed inflammatory changes. The normal pituitary tissue was displaced. Blood investigations showed a random cortisol of 93 nmol/l, TSH 0.5 mU/l, T4 8.6 pmol/l, FSH <1 unit/l, LH<1 unit/l, Testosterone <0.5 nmol/l and central diabetes insipidus with a serum sodium of 139 mmol/l, serum osmolality 295 mmol/kg and urine osmolality of 121 mmol/kg. Pituitary replacement therapy was initiated with hydrocortisone, thyroxine and desmopressin and he underwent urgent transsphenoidal debulking of the lesion. Histology revealed a cystic pituitary lesion with focal xanthogranulomatous inflammation in keeping with cyst rupture. His vision improved post operatively. An ophthalmic review showed 6/3.8 acuity in the right eye and 6/4.8 acuity in the left, mild loss of sensitivity in the temporal hemifield of the right but intact visual fields in the left eye. Repeat imaging in November 2021 showed a residual 16 mm sellar/suprasellar cyst with ongoing distortion of the anterior visual pathways, contact with the intracranial optic nerves and distortion of the optic chiasm. He represented in January 2022 with sudden onset blurred vision. Ophthalmic review showed 6/9 visual acuity in the left and 6/6 in the right eye, a new left relative afferent pupillary defect, and new bitemporal hemianopia. An MR Pituitary showed enlargement of the residual cystic lesion and further encroachment of the optic tract. He underwent urgent redo transsphenoidal endoscopic drainage of the cyst. His vision improved significantly post operatively. Visual fields were normal to confrontation. Histology showed a fragment of pituitary gland containing granulation tissue and stratified epithelium compatible with elements of a residual RCC.

Conclusion: In most RCCs the development of pituitary dysfunction and neuro-ophthalmic deficit are chronic. We present a rare case of a ruptured RCC causing acute visual problems and panhypopituitarism which recurred within a short period after decompression. The patient will remain under close clinical and radiological follow-up.