OJHAS Vol. 9, Issue 4:
Oct-Dec, 2010) |
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Craniopharyngioma - Transnasal Endoscopic Approach |
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Nitin Gupta, Assistant Professor,
Saurabh Varshney, Prof & HOD, SS Bist, Associate Professor, Sanjeev Bhagat, Assistant Professor,
Department of ENT, Himalayan Institute of Medical
Sciences, Jolly Grant. Doiwala, Dehradun (Uttarakhand) India –
248140. |
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Address For Correspondence |
Dr. Nitin Gupta, Assistant Professor, Department of ENT, Himalayan Institute of Medical
Sciences, Jolly Grant, Doiwala, Dehradun (Uttarakhand) India – 248140
E-mail:
nitinent123@gmail.com |
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Gupta N, Varshney S, Bist SS, Bhagat S. Craniopharyngioma - Transnasal Endoscopic Approach. Online J Health Allied Scs.
2010;9(4):22 |
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Submitted: Sep 12,
2010; Accepted Nov 2, 2010; Published: Jan 20, 2011 |
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Abstract: |
Craniopharyngiomas
are slow growing tumours arising from remnants of the craniopharyngeal
duct and occupy the sellar region. The patients may remain asymptomatic
for long duration or present with headache or visual disturbances. Surgery
is the mainstay of the treatment. Traditionally these tumours have been
removed by neurosurgeons through the cranial approach but the advent
of nasal endoscopes has opened new avenues for ENT surgeons to treat
such patients. We hereby present a case of craniopharyngioma who was
successfully treated by Trans-nasal Hypophysectomy.
Key Words: Craniopharyngioma;
Trans-nasal Hypophysectomy
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Craniopharyngioma
is a slow-growing, extra-axial, epithelial-squamous, calcified cystic
tumor arising from remnants of the craniopharyngeal duct and/or Rathke
cleft and occupying the sellar region.(1) Craniopharyngiomas are dysontogenic
tumors with benign histology and malignant behavior, as they have a
tendency to invade surrounding structures and recur after total resection.(2,3)
Craniopharyngioma usually presents as a single large cyst or multiple
cysts filled with a turbid, proteinaceous material of brownish-yellow
color that shines because of a high content of floating cholesterol
crystals. Because of its appearance, it has been compared to machinery
oil. It most frequently arises in the pituitary stalk and projects into
the hypothalamus. Incidence of craniopharyngiomas is 0.5-2 per 100,000
per year.(4) Craniopharyngioma accounts for 1-3% of intracranial tumors
and 13% of suprasellar tumors.(5) Symptoms frequently develop insidiously
and mostly become obvious only after the tumor attains a diameter of
about 3 cm. We are presenting one case that had mainly presented with
visual disturbances and was removed by Trans-nasal endoscopic Hypophysectomy.
Craniopharyngiomas are rare
intracranial tumours (0.5%) and it is even more rare to find them in a 20 year old,
as they are more common in 1st decade and then in 5th decade. Secondly we were
able to find and document the typical features of craniopharyngioma in this case
and the patient also recovered almost completely.
A 20 year
old male presented with complaints of progressive diminution of vision
in the left eye for 3 months and occasional headaches. Ophthalmic examination
revealed vision of 1/60 in the left eye and 6/24 in the right eye, with
optic atrophy of left eye on fundus examination. Multiplanar MRI imaging
of cranium was done. T1 and T2 weighted images were obtained in axial,
coronal and sagittal planes. Post Godolinium enhanced T1 weighted images
were subsequently acquired in all 3 planes. MRI revealed well defined
lobulated lesion of 2.9 cm x 2.6 cm in sellar and suprasellar region.
This lesion was hypointense on T2 weighted images with an iso to hypo
intense component within suggestive of mural nodule, whereas it was
hyper intense on T1 scans. Post contrast scan showed well defined peripheral
ring of enhancement. These findings were consistent with craniopharyngioma
of sellar and suprasellar pituitary. MRI Skull revealed a soft cystic
mass in infra sellar pituitary. (Fig. 1) Hormonal assay of the patient
was normal. The mass was removed by Trans- nasal endoscopic approach
in association with neurosurgeon. Oily coloured fluid suggestive
of craniopharyngioma was aspirated from the cystic mass before incision
over meninges. Vision of the right eye recovered completely 3
days postoperatively. A post operative CT scan done after 3 weeks
following surgery, showed complete removal of the mass (Fig. 2). HPE
of the excised mass showed features suggestive of craniopharyngioma.
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Fig 1: MRI Scan
showing Craniopharyngioma |
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Fig 2: Post
operative (after 3 weeks) CT Scan
showing tumor clearance |
Craniopharyngioma
is a slow-growing, extra-axial, epithelial-squamous, calcified cystic
tumor arising from remnants of the craniopharyngeal duct and/or Rathke
cleft and occupying the sellar region. Two main hypotheses explain the
origin of craniopharyngioma—embryogenetic and metaplastic. Embryogenetic
theory relates to development of the adenohypophysis and transformation
of the remnant ectoblastic cells of the craniopharyngeal duct and the
involuted Rathke pouch, while metaplastic theory relates to the residual
squamous epithelium (derived from stomodeum and normally part of the
adenohypophysis), which may undergo metaplasia.(6) Another theory which
explains the craniopharyngioma spectrum, attributing the adamantinous
type to embryonic remnants and the adult type to metaplastic foci derived
from mature cells of the anterior hypophysis is the dual theory. Craniopharyngiomas
are dysontogenic tumors with benign histology and malignant behavior,
as they have a tendency to invade surrounding structures and recur after
what was thought to be total resection. Craniopharyngioma usually presents
as a single large cyst or multiple cysts filled with a turbid, proteinaceous
material of brownish-yellow color that shines because of a high content
of floating cholesterol crystals.(2,5) Because of its appearance, it
has been compared to machinery oil. It most frequently arises in the
pituitary stalk and projects into the hypothalamus. Time interval between
onset of symptoms and diagnosis ranges from 1-2 years. The most common
presenting symptoms are headache (55-86%), endocrine dysfunction (66-90%),
and visual disturbances (37-68%). The diagnostic evaluation for craniopharyngioma
includes precontrast and postcontrast CT scans and MRI, Magnetic Resonance
Angiography (MRA), complete endocrinologic and neuro-ophthalmologic
evaluation with formal visual field documentation, as well as neuropsychological
assessment.(3,4) Imaging studies strongly suggest the diagnosis. The
radiologic hallmark of a craniopharyngioma is the appearance of a (supra)sellar
calcified cyst. About 80-87% of craniopharyngiomas are calcified and
70-75% is cystic. Calcifications are more common in children (90%) than
in adults (50%).CT scan is the most sensitive method to demonstrate
calcifications as high-density areas and has replaced the plain radiograph.
It is useful in defining both calcified and cystic parts. Cyst content
usually has the same density as CSF; contrast administration better
defines the enhancing cyst capsule.MRI, with its multiplanar capability,
is essential for defining the local anatomy and is the most important
imaging modality used to plan the surgical approach.MRA is used for
visualizing the major cerebral vessels and their relation to the tumor;
it has largely replaced the 4-vessel angiogram. The histologic spectrum
of craniopharyngioma includes 3 main types—adamantinomas, papillary,
and mixed. Adamantinomas consist of reticular epithelial masses, resembling
the enamel pulp of developing teeth. This is seen predominantly in children.
A distinctive feature is a palisading basal layer of small cells, which
encloses a loose stellate reticular zone, as well as areas of compactly
arranged squamous cells.(5) They contain nodules of keratin ("wet"
keratin), which are the hallmarks of this tumor subtype. Squamous papillary
type is composed of islands of squamous metaplasia, embedded in a connective
tissue stroma, with infrequent cystic degeneration and calcification.
Essentially, 2 main management options are available for craniopharyngioma—(1)
attempt at gross total resection or (2) planned limited surgery followed
by radiotherapy.(3,5) Gross total surgical removal is the treatment
of choice. Recurrence rates can be as high as 20%.Some authors propose
a plan of limited surgery, with postoperative radiotherapy as the management
paradigm of choice for craniopharyngioma. Goals of this approach are
(1) pathologic confirmation of the tumor and (2) surgical decompression
of the optic chiasma. Surgery is followed by external beam radiation,
at a dose of 5400-5500 cGy delivered at 180 cGy/fraction. Trans-nasal
endoscopic procedures have significantly reduced the morbidity associated
with this surgery. ENT surgeons can provide access to the pituitary
without any scar and the morbidity associated with the trans cranial
approach. Gamma Knife surgery has recently been used to treat craniopharyngiomas.
These procedures don't actually involve the use of a "knife"
or scalpel. In fact, no incisions are made at all. The skull never has
to be opened up. Gamma Knife also differs from conventional radiation
therapy. Because patients are injected with such low doses of radiation,
they don't experience the side effects associated with traditional radiation
therapy. In fact, several "shots" of therapy can be given
during the same session, and treatment sessions can be repeated every
few weeks if necessary.
- Bunin GR, Surawicz
TS, Witman PA. The descriptive epidemiology of craniopharyngioma. J Neurosurg
Oct 1998;89(4):547-551
- Hoffman HJ, De Silva
M, Humphreys RP. Aggressive surgical management of craniopharyngiomas
in children. J Neurosurg
Jan 1992;76(1):47-52.
- Rajan B, Ashley
S, Gorman C. Craniopharyngioma - a long-term result following limited
surgery and radiotherapy. Radiother Oncol
Jan 1993;26(1):1-10.
- Sanford RA. Craniopharyngioma:
results of survey of the American Society of Pediatric Neurosurgery.
Pediatr Neurosurg 1994;21 Suppl 1:39-43
- Tarbell NJ, Barnes
P, Scott RM. Advances in radiation therapy for craniopharyngiomas. Pediatr
Neurosurg 1994;21 Suppl 1:101-107
- Weiner HL, Wisoff
JH, Rosenberg ME. Craniopharyngiomas: a clinicopathological analysis
of factors predictive of recurrence and functional outcome. Neurosurgery
Dec 1994;35(6):1001-1010
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