|Ahead of print
Intrasphenoidal Rathke cleft cyst: A rare case report
Mahadevan S Gowtham1, Devaraj Sunilkumar1, Andi S Ramesh2, Bheemanathi H Srinivas3, Dinesh Verma2, Krishnan Nagarajan1
1 Department of Radio-Diagnosis, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Pondicherry, India
2 Department of Neurosurgery, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Pondicherry, India
3 Department of Pathology, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Pondicherry, India
|Date of Submission||05-Oct-2020|
|Date of Decision||11-Feb-2021|
|Date of Acceptance||24-Mar-2021|
|Date of Web Publication||07-Jan-2022|
Professor of Radio-Diagnosis, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Pondicherry 605006.
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Rathke cleft cysts are benign lesions of the sellar and suprasellar region. Extrasellar intrasphenoidal Rathke cleft cysts are rare with only one case reported in pediatric age group. The presenting complaints described include headache and diplopia. We report a case of intrasphenoidal Rathke cleft cyst in a 15-year-old girl who presented with headache and visual disturbances. Neuroimaging showed an expansile cystic lesion involving the sphenoid sinus with mass effect over the pituitary and optic chiasma. Endoscopic decompression of the cystic lesion was done and histopathology of the cyst wall revealed it to be Rathke cleft cyst. Follow-up MRI showed total resection of the cystic lesion with residual partial left optic nerve atrophy.
Keywords: Intra-sphenoidal cyst, MRI, Rathke cleft cyst (RCC), sellar lesion
| Introduction|| |
Rathke cleft cysts are benign unilocular epithelium-lined cysts arising from embryological Rathke pouch remnants. Most are small and asymptomatic with incidence of 12–33% in autopsy series. They are typically sellar or sellar-suprasellar in location and are amongst the common lesions in the sellar/suprasellar region. Intrasphenoidal Rathke cleft cysts are rare with only five cases reported till date.,,,, Among them, only one was from pediatric age group. In this report, we describe a case of intrasphenoidal Rathke cleft cyst in a 15-year-old girl who presented with headache and loss of vision.
| Case Report|| |
A 15-year-old girl presented with history of headache and vomiting for 4 days and progressive visual disturbances in left eye for 2 days. Ophthalmologic examination revealed loss of perception of light in left eye along with features of third and sixth cranial nerve palsy. Left pupil was slightly sluggish. Right eye examination was normal. Computed Tomography (CT) of brain showed a hyperdense expansile lesion in the sphenoid sinus with thinning and erosion of the walls of the sphenoid sinus and clivus with mass effect over the sella. Contrast CT did not show any enhancement [Figure 1]. Magnetic Resonance Imaging (MRI) was done in 1.5 Tesla scanner (Avanto Magnetom Siemens, Erlangen, Germany). Sphenoid region showed a T2/FLAIR hyperintense T1 isointense lesion with enlargement and thinning of the wall of the sinus. Thinning and erosion of the planum sphenoidale, dorsum sellae, and clivus were noted. Both anterior and posterior pituitary were separately seen from the lesion and displaced superiorly. There was mass effect over the optic chiasma with stretching of cisternal segment of bilateral optic nerves. Bilateral perioptic spaces were prominent. No diffusion restriction or hemorrhage was noted within the lesion. On post-contrast, thin rim of peripheral enhancement was seen [Figure 2]. The patient was taken up for trans-nasal endoscopic trans-sphenoidal decompression. Intra-operatively, anterior wall of the sella was thinned out, and it was eroded in few places to expose the lesion. Anterior sellar wall was drilled out, cyst was completely exposed and the wall was opened in a wide manner to drain yellowish mucous fluid. Cyst wall was removed and it was sent for histopathology. Histopathological examination showed cyst wall lined by ciliated columnar epithelium and stratified squamous epithelium at places confirming the diagnosis of Rathke’s cleft cyst [Figure 3]A and B. Post-surgery, the third cranial nerve deficits improved, but child had persistent impairment of left eye abduction (sixth nerve). Follow-up MRI showed no recurrence of lesion noted after 18 months of follow up with left optic atrophy [Figure 3]C.
|Figure 1: Plain (A), contrast (B) axial sections, and coronal reformation (C) showing homogenous subtle hyperdense lesion in sella-suprasellar region with slightly more left parasellar/cavernous sinus involvement (arrows). No contrast enhancement is noted|
Click here to view
|Figure 2: FLAIR axial (A), T2-weighted coronal (B), T1-weighted sagittal (C), diffusion-weighted image (D), and post-contrast T1 sagittal (E) sections showing T1 iso- T2/FLAIR hyperintense lesion (asterisk in A) with normal superiorly displaced pituitary (arrows in B and C) and bulging on left side (double arrows in B). The erosion of anterior sellar floor and tuberculum sellae upto the planum sphenoidale is noted (double vertical arrow in C). Immediate Post-operative CT (F) showing the air-filled cavity in the sphenoid (white asterisks)|
Click here to view
|Figure 3: Photomicrographs of (A) histopathology (H and E, ×100) showing cyst lined by ciliated columnar and squamous epithelium with underlying stroma. (B) High power (H and E, ×200) showing ciliated columnar epithelium with basally placed nuclei (arrow). Post-operative T1-weighted sagittal (C) section showing total removal of the lesion with normal enhancing pituitary in the sella (arrow)|
Click here to view
| Discussion|| |
Rathke cleft cysts are believed to arise from embryological Rathke pouch remnants. Between third and fourth gestational weeks, a rostral outpouching arises from primitive oropharynx which later forms anterior lobe, pars intermedia, and pars tuberalis of pituitary gland. This rostral outpouching from the oropharyngeal ectoderm is called Rathke pouch and forms the craniopharyngeal canal. At about the same time, infundibulum develops from diencephalon which later forms neurohypophysis. Both structures come in contact with each other at around fifth week of gestation forming the adenohypophysis and neurohypophysis, respectively. Rathke pouch regresses by sixth week of gestation into a narrow cleft. Rathke cleft cysts form due to the persistence and enlargement of these clefts and are usually located in pars intermedia. Similar to craniopharyngioma that can arise from any part of craniopharyngeal canal, they also may originate from the craniopharyngeal canal explaining their intrasphenoidal location. The parallel features of craniopharyngioma also explain the ectopic locations of Rathke cleft cysts like purely suprasellar location, pre-pontine, and cerebello-pontine angle cisterns.,,,,
Rathke cleft cysts are usually small and asymptomatic and identified as incidental finding. Larger lesions cause compression of optic chiasm, pituitary stalk, and hypothalamus and cause symptoms. Common symptoms include visual loss (most common in adults) followed by endocrine abnormalities and headache. Theoretically, Intrasphenoidal cyst, due to its atypical location may not present with endocrine abnormalities or visual symptoms. The commonest symptom of reported cases is headache followed by diplopia.,,, The child in our report had complete loss of vision in addition to headache and diplopia and it may be due to left-ward expansion of the cystic lesion causing some optic canal encroachment. On follow up, she developed left optic atrophy suggesting chronic compression. On CT, they appear as well-defined homogenous unilocular hypodense lesions typically in sella-suprasellar location. Calcification is uncommon though thin curvilinear peripheral calcification may be present. On T1-weighted MRI, two-thirds of Rathke cysts appear hyperintense and one-third hypointense relative to gray matter depending on the protein content within the cyst. On T2-weighted MRI, half of them show moderate to strong hyperintensity, 25% appear isointense with 25% appearing hypointense. On contrast administration, they do not enhance on CT or MRI except for thin rim enhancement. Histologically, these cysts are lined by cuboidal or columnar epithelium. The presence of areas of squamous metaplasia or stratified squamous epithelium linked to higher chance of recurrence. Although histopathogy is final confirmation, epithelial cystic lesions of sellar and suprasellar region can have overlapping histological features. Because of rare occurrence of Rathke cysts within the sphenoid, preoperative diagnosis may be difficult. Sphenoid sinus or bony lesions are uncommon lesions in children. In a review, Lui et al. classified sphenoid lesions in children into two major groups; benign lesion like mucocele, fibrous dysplasia, giant cell lesions, and aneurysmal bone cyst causing slow bone remodeling and malignant lesions like chordoma, rhabdomyosarcoma, neuroblastoma, etc. with erosive bone destruction. Other rare lesions reported include non-traumatic intra-diploic arachnoid cyst and lymphatic malformation., Though there are no specific imaging features, Rathke cysts should be considered in the differential diagnosis of cystic lesions of sphenoid region as management differs from mucoceles and cystic craniopharyngioma, the other common cystic lesions in the sphenoid region. Imaging is helpful for surgical approach and preservation of normal pituitary gland. Asymptomatic incidentally detected smaller cysts may be followed up and larger symptomatic ones are treated surgically. Surgical treatment involves cyst excision with drainage of contents through trans-sphenoidal route followed by biopsy of cyst wall. Recurrence rate of these lesions is estimated as 5% and depends on several factors such as squamous metaplasia of cyst wall, chronic inflammation, and aggressiveness of surgical approach.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
El-Mahdy W, Powell M Transsphenoidal management of 28 symptomatic Rathke’s Cleft cysts, with special reference to visual and hormonal recovery. Neurosurgery1998;42:7-16. doi: 10.1097/00006123-199801000-00003
Kalina P, Rykken J Pediatric sphenoidal Rathke’s cleft cyst. J Pediatr Neuroradiol 2012;1:313-6. doi: 10.3233/PNR-2012–040
Megdiche-Bazarbacha H, Ben Hammouda K, Aicha AB, Sebai R, Belghith L, Khaldi M, et al
. Intrasphenoidal rathke cleft cyst. AJNR Am J Neuroradiol 2006;27:1098-1100.4.
Kocaman U, Yilmaz MB, Yilmaz H Intrasphenoidal Rathke’s Cleft Cyst: case presentation and review of the literature. Romanian Neurosurg 2016;30:520-5. doi: 10.1515/romneu-2016-0083
Kasliwal MK, Dua SG, Harbhajanka A, Nag S, Jhaveri MD, Moftakhar R Intrasphenoidal Rathke’s cleft cyst. J Clin Neurosci 2015;22:1678-82. doi: 10.1016/j.jocn.2015.05.001
Pojskic M, Zbytek B, Beckford NS, Boop FA, Arnautovic KI First report of coexistence of two ectopic pituitary tumors: Rathke cleft cyst and silent adrenocorticotropic hormone adenoma. World Neurosurg 2017;104:1048.e1-7.
Barrow DL, Spector RH, Takei Y, Tindall GT Symptomatic Rathke’s cleft cysts located entirely in the suprasellar region: review of diagnosis, management, and pathogenesis. Neurosurgery 1985; 16:766-72.
Hanna E, Weissman J, Janecka IP Sphenoclival Rathke’s cleft cysts: embryology, clinical appearance and management. Ear Nose Throat J 1998;77:396-9.
Chuang CC, Chen YL, Jung SM, Pai PC A giant retroclival Rathke’s cleft cyst. J Clin Neurosci 2010;17:1189-91.
Zhou L, Luo L, Hui X, Chen H, Yu B, Guo G, et al
. Primary Rathke’s cleft cyst in the cerebellopontine angle associated with apoplexy. Childs Nerv Syst 2010;26:1813-7. doi: 10.1007/s00381-010-1270-3
Kim E A case of ectopic Rathke’s cleft cyst in the prepontine cistern. J Korean Neurosurg Soc 2012;52:152-5. doi: 10.3340/jkns.2012.52.2.152
Larkin S, Karavitaki N, Ansorge O Rathke’s cleft cyst. Handb Clin Neurol 2014;124:255-69. doi: 10.1016/B978-0-444-59602-4.00017-4
Lui YW, Dasari SB, Young RJ Sphenoid masses in children: radiologic differential diagnosis with pathologic correlation. AJNR Am J Neuroradiol 2011;32:617-26. doi: 10.3174/ajnr.A2144.
Lahiri AK, Chilvers G Nontraumatic intradiploic arachnoid cyst of the sphenoid bone. Radiol Case Rep 2018;13:576-9. doi: 10.1016/j.radcr.2018.02.011.
Bennett G, April M, Huvos AG Lymphatic malformation of the sphenoid sinus in a pediatric patient. Otolaryngol Head Neck Surg 2004;131:784-6. doi: 10.1016/j.otohns.2004.02.010.
Voelker JL, Campbell RL, Muller J Clinical, radiographic, and pathological features of symptomatic Rathke’s cleft cysts. J Neurosurg 1991;74:535-44. doi: 10.3171/jns.1991.74.4.0535
[Figure 1], [Figure 2], [Figure 3]