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O al-Mefty

Publications and source records attributed to O al-Mefty.

44 records · Page 3Linked to original sources

The long-term side effects of radiation therapy for benign brain tumors in adults.

Radiation therapy plays an integral part in managing intracranial tumors. While the risk:benefit ratio is considered acceptable for treating malignant tumors, risks of long-term complications of radiotherapy need thorough assessment in adults treated for benign tumors. Many previously reported delayed complications of radiotherapy can be attributed to inappropriate treatment or to the sensitivity of a developing child's brain to radiation. Medical records, radiological studies, autopsy findings, and follow-up information were reviewed for 58 adult patients (31 men and 27 women) treated between 1958 and 1987 with radiotherapy for benign intracranial tumors. Patient ages at the time of irradiation ranged from 21 to 87 years (mean 47.7 years). The pathology included 46 pituitary adenomas, five meningiomas, four glomus jugulare tumors, two pineal area tumors, and one craniopharyngioma. Average radiation dosage was 4984 cGy (range 3100 to 7012 cGy), given in an average of 27.2 fractions (range 15 to 45 fractions), over a period averaging 46.6 days. The follow-up period ranged from 3 to 31 years (mean 8.1 years). Findings related to tumor recurrence or surgery were excluded. Twenty-two patients had complications considered to be delayed side effects of radiotherapy. Two patients had visual deterioration developing 3 and 6 years after treatment; six had pituitary dysfunction; and 17 had varying degrees of parenchymal changes of the brain, occurring mostly in the temporal lobes and relating to the frequent presentation of pituitary tumors (two of these also had pituitary dysfunction). One clival tumor with the radiographic appearance of a meningioma, developed 30 years post-irradiation for acromegaly. This study unveils considerable delayed sequelae of radiotherapy in a series of adult patients receiving what is considered "safe" treatment for benign brain tumors.

Adult↗

Zygomatic approach to skull-base lesions.

A modification of the preauricular skull-base approach is described. After sectioning and downward displacement of the zygomatic arch, the coronoid process of the mandible is dissected and sectioned at its base. The temporal muscle, with its coronoid insertion, is then retracted upward. This approach provides direct and unobstructed access to the temporal and infratemporal fossae. Adequate vascularity of the temporal muscle is maintained. The exposure encompasses the internal carotid artery in the neck for vascular control. Extensive reconstruction is eliminated. The described technique was used in seven patients with lesions of the skull base. There was no operative mortality, and morbidity consisted of temporary restriction of mandibular opening in two patients.

Adult↗

Synovial cyst at the craniovertebral junction.

A case of synovial cyst of the upper cervical spine that resulted in spastic quadriparesis and sensory loss is reported. Radiographic evaluation included a computed tomography scan after myelography and a magnetic resonance imaging scan. The synovial cyst was removed by a laminectomy at C-1 and C-2, combined with a foramen magnum craniectomy. The patient had a good recovery.

Aged↗

The surgical anatomy of the cerebral sulci.

Intraventricular and intra-axial lesions can be reached through a transsulcal approach, avoiding the more extensive cerebral tissue damage that may result from a conventional cortical incision. The sulci of five cadaver brains fixed in formalin solution were dissected using the operating microscope. The brains were photographed for surface mapping and x-rays to demonstrate underlying ventricular relationships were taken. The brains were then coronally sectioned to characterize anatomical relationships between sulci and deep brain structures. Three important sulci were identified and thoroughly characterized with respect to surface relationships, average depth, and underlying structures that can be readily approached. Surgical application of these findings is discussed.

Cerebral Cortex↗

The low incidence of cerebral aneurysms in the Middle East: is it a myth?

It is common belief that there is a relatively low incidence of cerebral aneurysm in the Middle East; however, there are neither routine autopsy studies nor reliable public health data to confirm this impression. We analyzed the clinical data of all patients admitted with a diagnosis of nontraumatic subarachnoid hemorrhage to the King Faisal Specialist Hospital, a modern tertiary medical center in Riyadh, Saudi Arabia. These data were compared with reports from other countries. Although environmental or inherited factors may predispose to a lower incidence of intracranial aneurysm in the Middle East, the true incidence is higher and is not apparent because of the previous referral system for medical care. Medical facilities and expertise are rapidly improving, and future studies undoubtedly will show a higher incidence of intracranial aneurysm.

Adolescent↗

Transient ischemic attacks due to increased platelet aggregation and adhesiveness. Ultrastructural and functional correlation.

The authors report 22 cases of transient ischemic attacks (TIA's) manifested by amaurosis fugax or hemiparesis or paresthesia of less than 24 hours' duration. None of the patients demonstrated 1) evidence of atherosclerotic cerebral vascular disease on angiography, 2) evidence of intracranial lesion on brain scan, 3) cardiac source of emboli, 4) arteritis or collagen disease, or 5) history of migraine. The only abnormalities found to explain the TIA's were abnormally increased platelet adhesiveness and/or aggregation. All of these patients were followed from 1 to 5 years, and had repeated coagulation studies. Treatment with antiplatelet drugs showed an excellent clinical response with associated decrease in platelet adhesiveness and aggregation. Discontinuance of the antiplatelet drug resulted in a recurrence of the TIA's which coincided with an increase in aggregation and adhesiveness. In two cases the platelet morphology was studied by transmission and scanning electron microscopy. It appears that there is a specific group of patients with TIA's in whom the sole cause of the attack is an abnormality of platelet function. For these people there is a specific therapy and a method monitoring the treatment.

Adolescent↗