This document discusses congenital abnormalities of the sellar and parasellar regions. It begins by stating that the aim is to show the embryological correlations of the pituitary gland and how knowledge of these correlations allows for understanding of congenital abnormalities in these regions. It then discusses MRI as the preferred imaging technique for evaluating these types of pathologies. The document goes on to provide examples of various congenital abnormalities that can be seen in the sellar and parasellar regions through MRI images, including transsphenoidal encephalocele, hypoplastic pituitary gland, ectopic posterior pituitary, hypothalamic hamartoma, infundibular hypoplasia, Rathke's cleft cyst, cranioph

1. Congenital abnormalities of the
sellar and para-sellar regions.
Dr/ ABD ALLAH NAZEER. MD.

2. Aim of the lecture.
To show the embryological correlations
of the pituitary gland with adjacent
structures which allow knowledge of
interpretation of the sellar and para-
sellar congenital abnormalities.
Also to show imaging appearance of
the congenital diseases of the sellar
and para-sellar regions. .

11. Technique:
MRI is the examination of choice for sellar and para-sellar
pathologies due to its superior soft tissue contrast,
multiplanar capability and lack of ionizing radiation. In
addition, MRI also provides useful information about the
relationship of the gland with adjacent anatomical
structures and helps to plan medical or surgical strategy.
MRI techniques in diagnosing pituitary lesions have
witnessed a rapid evolution, ranging from non-contrast MRI
in late 1980s to contrast-enhanced MRI in mid-1990s.
Recently, a variety of advanced MR techniques have been
evolved which are particularly helpful in evaluating specific
cases. These include 3D volumetric analysis of pituitary
volume, high-resolution MR imaging at 3 Tesla (T) for
evaluating pituitary stalk.

12. The aim of MR imaging is to obtain a high-
spatial-resolution image with a reasonable
signal to noise ratio. It is important to identify
the gland separate from the lesion if possible.
Initially, pre-contrast T1- and T2-weighted spin
echo coronal and sagittal sections are acquired
using a small FOV (20×25 cm), thin slices (2-3
mm), and high-resolution matrix (256×512).
Both the dynamic and routine post-contrast
images and delayed scanning after 30-60
minutes may be combined in one study for
optimum imaging.

13. Parameters.
TR TE FLIP NXA SLICE MATRIX FOV PHASE OVERSAMPLE GAP
3000-4000 110 130 4 2-3mm 256x512 100-130 R> L 100% 10%

16. Normal
postnatal
progression of
the pituitary
gland.

19. Transsphenoidal encephalocele.
MRI and CT images of transsphenoidal encephalocele.

22. Markedly hypoplastic pituitary with absent bright spot. (A) Sagittal non-
contrast T1- weighted and (B) contrast-enhanced T1-weighted imaging
shows almost complete absence of the gland with an associated shallow
sella (arrowheads). The upper infundibulum is present but the characteristic
high T1-weighted signal is not seen on non contrast imaging.

23. Anterior pituitary aplasia and posterior pituitary ectopia. No
anterior pituitary gland identified with a thin infundibulum.

28. Sagittal MRI of the hypothalamic−pituitary axis. The pituitary (lower arrow)
is small and scalloped. There is absence of the normal posterior pituitary and
stalk in and above the pituitary fossa, and an ectopic posterior pituitary
bright spot where the infundibulum normally is (upper arrow).
Ectopic neurohypophysis
with small pituitary gland.

29. Ectopic posterior pituitary gland and the
pituitary gland is hypoplastic (arrowhead).

36. Hypothalamic
hamartoma.

39. Infundibular hypoplasia..

40. Congenital disorder.
Development of the adenohypophysis.

43. Rathke,s Cleft Cyst:
CT :
•75% hypodense
•25% iso/hyperdense
•Ca++ rare
•May be difficult to differentiate from other benign cysts or
craniopharyngioma.

46. Rathke,s cleft cyst.

50. Sagittal T1W, Fluid suppressed T2W and post contrast
T1W images showing craniopharyngioma in child.

53. Pars Intermedia Cyst.

54. Miscellaneous.

56. Dermoid cyst.

57. Right para-and supra-sellar dermoid cyst.

60. Para-sellar teratoma.

61. THANK YOU.