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Year : 2012  |  Volume : 60  |  Issue : 5  |  Page : 534--536

Ossified rathke's cleft cyst: A rare variant

Mudumba Vijayasaradhi1, Vangala Bramha Prasad1, Megha S Uppin2, Challa Sundaram2,  
1 Department of Neurosurgery, Nizam's Institute of Medical Sciences, Hyderabad, Andhra Pradesh-500082, India
2 Department of Pathology, Nizam's Institute of Medical Sciences, Hyderabad, Andhra Pradesh-500082, India

Correspondence Address:
Mudumba Vijayasaradhi
Department of Neurosurgery, Nizam«SQ»s Institute of Medical Sciences, Hyderabad, Andhra Pradesh-500082
India




How to cite this article:
Vijayasaradhi M, Prasad VB, Uppin MS, Sundaram C. Ossified rathke's cleft cyst: A rare variant.Neurol India 2012;60:534-536


How to cite this URL:
Vijayasaradhi M, Prasad VB, Uppin MS, Sundaram C. Ossified rathke's cleft cyst: A rare variant. Neurol India [serial online] 2012 [cited 2020 Apr 5 ];60:534-536
Available from: http://www.neurologyindia.com/text.asp?2012/60/5/534/103214


Full Text

Sir,

Rathke's cleft cysts (RCC) are predominantly sellar-suprasellar lesions thought to arise from remnants of embryologic Rathke's pouch during fourth week of development. The presence or the absence of calcification is an important feature in distinguishing them from other commonly encountered cystic lesions in the sellar-suprasellar region. [1] Craniopharyngiomas very commonly show calcifications and the presence of the same is uncommon in Rathke's cleft cyst. The case presented here is one of such uncommon variants.

A 45-year-old female presented with secondary amenorrhoea and infertility of 10 years duration with 6 months history of onset of headaches and visual disturbances. Examination of visual fields showed bi- temporal hemianopia. Evaluation of serum hormones showed low levels of follicle stimulating hormone (FSH) (1.48 mIU/ml; normal 3-10 mIU/ml) and luteinizing hormone (LH) (0.23 mIU/ml; normal 3-10 mIU on day 3) and normal levels of prolactin, growth hormone, cortisol (8 am value), and T3, T4, and thyroid stimulating hormone (TSH). Magnetic resonance imaging (MRI) revealed a well-defined oval (2.4 x 2.4 x 2.7 cm) T1- weighted isointense and T2-weighted hyperintense lesion with a surrounding faint rim of hypointensity in sellar region extending into the suprasellar compartment and compressing the optic chiasm and displacing it superiorly. The contrast study showed peripheral rim of enhancement [Figure 1]. Complete surgical excision of the lesion was performed by a right pterional craniotomy and trans-sylvian approach. Peroperatively the lesion was cystic and contained about 10 ml of xanthochromic fluid and was surrounded circumferentially by an unusual egg shelllike calcified hard layer which was removed near totally [Figure 2]. Histopathology of the cyst wall showed flattened to columnar epithelial lining of the cyst wall with focal stratification and keratinisation was not seen. Sub-epithelial tissue showed ossification [Figure 3]. Immunohistochemistry with pancytokeratin was positive in the lining of the cyst wall suggestive of RCC [Figure 4].{Figure 1}{Figure 2}{Figure 3}{Figure 4}

Clinically, RCCs are mostly asymptomatic and occasionally may present with varied symptoms like visual disturbances, headache, and amenorrhea/galactorrhoea due to pressure effects on the adjacent neural structures. On histology, RCC's usually have a lining by columnar or cuboidal epithelium with stratification, cilia, or goblet cells. They might sometimes contain gland like structures in the sub-epithelial layer. In suprasellar examples, the cyst wall may show squamous epithelium. [1] Histology in our patient showed flattened to ciliated epithelium with no keratinization thereby differentiating it from craniopharyngioma and other epithelial cysts in the sellar-suprasellar region. The expression of cytokeratins 8 and 20 was positive in RCC but not in craniopharyngioma. [2] The contents of the cyst were xanthochromic indicating old hemorrhage. The calcification and ossification seen in the cyst wall could be a consequence of old hemorrhage or caused by osteoid metaplasia in mesenchymal cells by inflammatory, chemical, or mechanical stimulation causing metaplastic ossification of the wall. [3]

In a study of 11 symptomatic patients by Rao and colleagues, 8 patients initially had visual symptoms. [4] In another study of 19 patients by Eguchi and co-authors, visual symptoms occurred in 47% of patients, 4 patients had diabetes insipidus, 3 patients had amenorrhea and/or galactorrhea, and 2 of the 19 patients had panhypopituitarism. [5] In the study by Voelker and colleagues, [6] the most common finding was pituitary hypofunction with multiple endocrinopathies. Younger patients, aged 4-22 years, had evidence of hypopituitarism from an early age, with resultant growth retardation. The second most common symptom was visual disturbance, which included visual field defects resulting from chiasmatic compression. The next most common symptom was headache, of which 57% were frontal. Shin and co- authors described impotence or low libido as the most common endocrine abnormality in men; in women the most common manifestation was hyperprolactinemia. [7] The case presented here had symptoms of headache, visual disturbances in the form of bitemporal hemianopia, and primary infertility. She was evaluated outside for infertility and was found to have normal reproductive anatomy except for low FSH and LH levels. On further evaluation she was detected to have a cystic sellar-suprasellar lesion with calcification. A preoperative CT scan would have been ideal for detection of calcification but was not done as the possibility of rathke's cleft cyst was not suspected initially. Our patient had selective deficiency of serum FSH and LH, other hormones being in the normal range which explains the cause of her infertility. Her post operative course was uneventful except for transient hyponatremia for initial few days which later subsided with dietary supplementation and also improvement in headache and vision at the end of 1 year follow up.

References

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