الفهرس 
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Abstract
Tumors of the pineal region account for just 0.5% to 1% of the
human brain tumors and they present a challenge to any neurosurgeon.
The pineal region is limited dorsally by splenium of the corpus
callosum and tela choroida, ventrally by quadrigeminal plate, rostrally by
posterior part of third ventricle and caudally by the vermis of cerebellum.
The physiologic role of the pineal gland itself is not completely
understood. Melatonin is essential in regulating circadian rhythms. The
absence of production of melatonin, as after pinealectomy causes a (jet-lag) like syndrome causing complete disturbance of circadian rhythms.
The pathologic classification of the pineal region tumors divides
them into several different groups including germ cell tumors, pineal
parenchymal tumors, tumors of supporting and adjacent structures,
metastatic tumors of the pineal gland, non neoplastic mass lesions in
pineal region.
The clinical presentation of the pineal region tumors includes
hydrocephalus, Parinaud’s syndrome, thalamic affection, dementia and
manifestations of meningeal seeding. Investigations include laboratory
measures of the tumor markers secreted by some tumors in both blood
and CSF and computerized tomography (CT) and magnetic resonance
imaging (MRI).
The treatment of the pineal region tumors has been intensively
debated for the past 40 years, today the treatment should involve three
principles 1) Control the hydrocephalus either by ventriculo-peritoneal
shunt or endoscopic 3
rd
ventriculostomy with the benefit of endoscopic
biopsy. 2) Total resection of benign encapsulated tumors of the pineal
region and 3) Histopathologic identification of non resectable tumors and
adjuvant treatment with radiotherapy and chemotherapy.
The pineal region and the third ventricle are located in the
geometrical center of the intracranial cavity so operative approaches from
every angle have been developed; the most common two approaches are
the infratentorial supracerebellar and the occipital transtentorial.
Recently, stereotactic radiosurgery are adverted for the
management of pineal region tumors with best results for tumors in the
pediatric population and must be less than 3 cm in diameter.
In this study 25 cases with pineal region tumors have been attacked
surgically using the supracerebellar-infratentorial approach, and occipital
transtentorial approach. Most of the patients’ symptoms and signs were
those of increased intracranial tension. Tumor markers were positive only
in one case of germ cell tumor. All the cases investigated by MRI before
starting the management and all cases presented with hydrocephalus were
treated by ventriculo-peritoneal shunt and ETV.
All the cases operated upon via supracerebellar infratentorial
approach in the sitting position and occipital transtentorial approach
aiming to total excision in benign tumors and aggressive excision in
malignant tumors to get much benefits of adjuvant therapy. Cases
needing postoperative adjuvant therapy received radiotherapy and
chemotherapy. The patients were followed up for 2 years.