Rathke cleft cyst

   February 13, 2020  Posted in Central Nervous System

Clinical:

  • A 55 years old lady
  • Para 1, last child birth 13 years ago (2007)
  • Conceived spontaneously, breast feeding for 12 months
  • Initial presentation in 2008 at 43 years old with galactorrhoea
  • At that time already stop breast feeding
  • Remained amenorrhoea after that
  • No headache, no visual impairment
  • Biochemical showed increased prolactin, normal TSH
  • Prolactin level normalized after treatment with dopamine agonist

 

 

MRI in sagittal plane (A) T1WI, (B) T2WI and (C) T1+Gado
MRI in T2-weighted sequences; (D) Sagittal and (E) Coronal plane.

MRI findings:

  • A well defined rounded lesion in the sella, centrally located (yellow arrows)
  • isointense on T1, hyperintense on T2 and not enhancing post contrast
  • The lesion is located between anterior and posterior lobe of pituitary gland (red arrow)
  • The lesion is very small measuring 4x3x2 mm
  • No intralesional nodule seen
  • No fluid levels within the lesion
  • No other lesion in the brain parenchyma

Diagnosis: Rathke cleft cyst

Discussion:

  • Rathke cleft cysts (RCCs) are benign, epithelium-lined intrasellar cysts believed to originate from remnants of the Rathke pouch.
  • They are found in 13-33% of the general population
  • Female preponderance; female to male ratio 2:1
  • On imaging, it is seen as a well defined non-enhancing midline cyst within the sella arising between the anterior and intermediate lobes of the pituitary. 40% are purely intrasellar and 60% have suprasellar extension. Purely suprasellar location, although reported, is rare.
  • CT scan demonstrate a hypodense lesion, non-calcified, non enhancing lesion.
  • MRI appearance depends on fluid content which may be mucoid or serous. On T1WI, 50% are hypointense and 50% are hyperintense. On T2WI, 70% are hyperintense and 30% are hypointense.
  • Presence of intralesional nodule is pathognomonic and seen in 75% of cases (not seen in this case).
  • Differentiation with cystic pituitary adenoma: fluid fluid levels usually seen in adenoma due to hemorrhage, location non-central in pituitary adenoma and abscence of intralesional nodule

 

Progress of patient:

  • Patient continues medical treatment
  • Follow up MRI for 4 consecutive years show no change in the lesion

Acknowledgement:

  • Dr Raja Nurazni, Endocrinologist
Author: radhianahassan