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Biomedical subjects

T Ozgen

Publications and source records attributed to T Ozgen.

At least 37 records · Page 2Linked to original sources
PubMed1996

Twenty-five years experience in the treatment of trigeminal neuralgia. Comparison of three different operative procedures in forty-nine patients.

A series of 49 patients with trigeminal neuralgia (TN) were treated by three different surgical procedures: (1) peripheral ablative procedures in 10 patients; (2) percutaneous rhizotomy in 17 patients and (3) intracranial rhizotomy (IR) in 22 patients. On the basis of surgical treatment, the concept that neurovascular compression is a mechanical factor in the aetiology of TN was supported in 14 to 18 patients who underwent posterior fossa exploration. The results support the conclusion that retromastoid craniectomy with IR is the procedure of choice for the majority of patients with TN.

Adult↗
PubMed1996

Endoscopic evacuation of sacral hydatid cysts: case report.

A case of hydatid disease of the intra and parasacral area is reported. This rare localization was probably due to previous abdominal hydatid cyst surgery. The patient underwent surgery, with a small opening in the SI lamina and the cysts were removed totally with the aid of a rigid endoscope. The surgical technique used and MRI findings are discussed.

Adolescent↗
PubMed1996

Factors affecting morbidity and mortality following surgical intervention in patients with intracranial meningioma.

BACKGROUND: Meningiomas usually grow slowly but they may cause recurrences despite surgical resection. The impact of clinical, neuroradiological and surgical characteristics on operative morbidity and mortality of patients operated on for intracranial meningioma was analysed. METHODS: A series of 450 patients operated on for intracranial meningiomas at the Department of Neurosurgery, Hacettepe University Hospital during the period 1964-1992 is reported. The surgical results were analysed with regard to intracranial site, extent of removal, histological type, and different time periods. Computed tomography (CT) and magnetic resonance imaging (MRI) facilitated the diagnosis and helped with the planning of treatment. RESULTS: Two hundred and ninety-two patients were examined with both CT and MRI. Overall mortality was 4% but showed a decline from 9% in the pre-CT era to 3% in the post-CT era and to 1% in the past 3 years. CONCLUSIONS: Operative mortality and recurrence rates are affected by the intracranial location of the tumour, histological type, and extent of tumour removal. Emphasis is also given to the importance of the introduction of the imaging techniques, and the microsurgical techniques with the Cavitron ultrasonic surgical aspirator (CUSA), laser, and/or bipolar coagulator which have further improved the operative mortality and recurrence rates.

Adolescent↗
PubMed1995

Congenital nasal encephalocele: a review of 35 cases.

Congenital encephaloceles are rare lesions which are usually seen in the occipital region, in the West. They may rarely be seen in the frontal region and they have distinct diagnostic features, together with several other pathological conditions occurring in this region. In order to emphasize these points, a retrospective analysis of 35 cases which have been operated on in our clinic, is made in this study. The findings are compared with the data obtained from the literature.

Bone Transplantation↗
PubMed1995

Applying critical pressure to middle cerebral artery in dogs.

The purpose of our model was to provide maximum pressure level of the middle cerebral artery (MCA) without causing any histological variation like focal cerebral ischaemia. In this experimental study 9 dogs were used. A modified Spetzler occluder was applied to the MCA of the dogs to determine regional cerebral blood flow (rCBF) and somatosensory evoked potentials (SSEP). Seven animals underwent the surgical procedure with measurements of rCBF after arterial microdissection and then after applying 80% blood pressure (BP) to the MCA for 15 minutes. In rCBF a 29% average reduction was observed. The average value of rCBF at the end of 15 minutes was 63.5 +/- 6.52 ml/100g min. Simultaneous somatosensory evoked potential recordings were also obtained. When rCBF was reduced 29%, 80% BP applying to MCA did not cause complications.

Animals↗
PubMed1994

Brainstem auditory evoked potentials and blink reflexes in patients with pontocerebellar angle tumors.

Brainstem auditory evoked potentials (BAEP) and blink reflexes (BR) were obtained from 13 patients with pontocerebellar angle (PCA) tumors whose pathological diagnosis was as follows: 7 acoustic neurinoma, 3 meningioma, 1 neurinoma, 1 brain stem epidermoid tumor, 1 arteriovenous malformation. The most prominent abnormality was noted in BAEP generated by stimulating the ear ipsilateral to the lesion and ipsilateral R1 reflexes obtained from ipsilateral stimulation of the supraorbital nerve.

Acoustic Stimulation↗
PubMed1994

Morphological assessment in pinealectomy and foetal pineal gland transplantation in rats: Part I.

The effects of pineal gland, an endocrine organ known to affect the physiology of various organs and systems including the hypothalamo-hypophyseal axis, on the morphological characteristics of target organs were investigated in rats after pinealectomy and foetal pineal gland transplantation to a subpial cortical area close to the pinealectomized region. It was demonstrated that weight gain was significantly slower in pinealectomized male rats (p < 0.01); pituitary gland weight was lower in the pinealectomized group (p < 0.01) and transplantation had no effect on the weight of this organ; weight of adrenal gland and testis were lower after pinealectomy (p < 0.01) but restored back to control levels after transplantation; the mitotic activity in seminiferous tubules increased with pinealectomy and returned back to control indexes after transplantation. Research on hypothalamic catecholaminergic content revealed a diminished histofluorescence in pinealectomized rats which showed a potentiated restoration after transplantation. The innervation of the pineal gland was studied by anterograde and retrograde injections of Wheat Germ Agglutinin Horse Radish Peroxidase from superior cervical ganglion and pineal gland, respectively. It was demonstrated that cell bodies were traced both at the transplanted tissue and hypothalamus. In view of these data, the multifunctional and a probable high level homeostatic harmony regulator essence of pineal gland is discussed.

Adrenal Glands↗
PubMed1994

Behavioural assessment of pinealectomy and foetal pineal gland transplantation in rats: Part II.

Pineal gland is an endocrine organ which exerts regulatory effects on the activity of various organs and systems. The present study was undertaken to highlight in experimental animals the possible integrative function of this endocrine organ on a behavioural pattern. Pinealectomy and foetal pineal gland transplantation to a subpial cortical area close to the pinealectomized region was performed. Behaviour was defined through motor activity induced by low (2 mg/kg) and high (10 mg/kg) doses of amphetamine in rats. It was shown that pinealectomy produced significant different patterns of behaviour induced by low and high doses of amphetamine. In sham operated animals low dose amphetamine induced a significant locomotor stimulation but without stereotyped activity. High dose amphetamine induced stereotyped activity. After pinealectomy even low dose amphetamine produced the behavioural pattern of stereotyped activity resembling a high dose amphetamine-induced behaviour. This differential effect of amphetamine, seen in pinealectomized rats, was completely restored after transplantation. On the other hand, melatonin treatment did not generate a significant alteration of behavioural profile either in the control or pinealectomized group of rats. Results are discussed with regard to the general regulatory function of the pineal gland.

Amphetamine↗
PubMed1994

Ossified adamantinous type craniopharyngiomas. A series of 13 patients.

Thirteen patients admitted to hospital mainly with visual disturbances (100%), retarded growth (39%) and diabetes insipidus (23%) were all diagnosed as ossified adamantinous craniopharyngioma. Tumour size was found to be large in all patients. Localization displayed a heterogenous dissemination; 8% intra-suprasellar, 69% suprasellar-extraventricular, 15% extra-intraventricular, and 8% in the suprasellar region extending bilaterally to the frontal and temporal lobes. During the early postoperative period, four patients died with hypothalamic deterioration. Three patients underwent a second operation in view of recurrence, and one died from an infection. Thus, the postoperative survival rate was 62%. All the patients who survived continued to have visual disturbances, but only one deteriorated. Five patients exhibited diabetes insipidus during the postoperative period, among them 4 after surgical intervention and 5 patients displayed panhypothyroidism, three of them after surgery. Consequently, it is confirmed by the present review that craniopharyngiomas still offer a potential dilemma in their management. Difficulties caused by adhesion or invasion of ossified craniopharyngiomas and thus the increase in morbidity and mortality during surgical intervention and in the postoperative period are discussed.

Adolescent↗
PubMed1994

Benign extramedullary tumors in the foramen magnum region.

We present 16 cases of benign extramedullary tumors of the foramen magnum region who were operated on between the years 1984 and 1992. On admission, no case was neurologically intact and over 50% had had symptoms for more than 1 year. Nine patients had erroneous diagnoses initially. CT myelography and magnetic resonance (MR) imaging were the most appropriate diagnostic tools in visualizing tumors of this region. All operations except one, were performed by the posterior approach without surgical mortality. Histopathological examination revealed 8 meningiomas, 6 neurinomas, one tuberculous abscess and one neurenteric cyst which has not been reported at this location before. Patients with minor to moderate disability on admission showed good functional results without any recurrences during follow-up.

Adolescent↗
PubMed1993

Status epilepticus following iohexol myelography.

Iohexol, a contrast medium widely used for myelography, has rarely been reported to cause convulsive disorders. A case of status epilepticus resulting from iohexol myelography is reported and problems of treatment are discussed.

Adult↗
PubMed1993

Topical effect of bromocriptine on rat-transplanted human prolactinomas.

In prolactinoma surgery, especially in macro-adenomas, it is not always possible to remove the tumour totally. Cell remnants may cause a regrowth and continue hypersecretion. In order to find out whether tumour remnants could be destroyed by local application of bromocriptine, a research model has been designed. First, prolactin secreting pituitary tumours, removed during surgery, were implanted bilaterally into the brain tissue of rats. In eight rats, the viability of tumour transplants was proven histopathologically and their prolactin secretion was shown immunocytochemically. In a second step, on eight rats, sterile bromocriptine solution was applied topically to the tumour transplants on one side. The other side served as control. Histopathological examination of these treated tissues revealed fibrosis. Immunocytochemical analysis showed no secretory activity. Ultrastructural investigations also revealed evidence of degeneration of the treated cells. The natural course of the transplanted tumour tissues of the other side, as a control group, was also observed during the same 55-day period.

Animals↗
PubMed1993

Spinal dural arteriovenous fistula adjacent to a spinal neurofibroma--a misleading coexistence. Case report.

The authors report the case of a patient harbouring a spinal dural arteriovenous fistula adjacent to an intradural neurofibroma. Only the latter could be demonstrated by the diagnostic modalities employed. Such a coexistence proved misleading and two interventions were needed to cure both lesions. Only one report has appeared in the literature dealing with such a condition. The possibility of such a coexistence is stressed and mechanisms are discussed.

Adult↗
PubMed1993

Treatment of intracranial abscesses: experience with sulbactam/ampicillin.

In an open prospective study, the efficacy of sulbactam/ampicillin (50 and 100 mg/kg, respectively, qid) was evaluated in 21 patients with intracranial abscess(es). Sixteen patients had cerebral, 3 epidural, and 2 cerebellar abscesses. Multiple lesions were found in 7 patients. Sixteen patients underwent surgical intervention, others were treated with antibiotic alone. The mean duration of antibiotic therapy (+/- SD) was 48 +/- 10 days (range 26-65 days). The mean duration of follow-up after completion of therapy (+/- SD) was 6 +/- 2.4 months. All patients had at least some reduction in size of abscess(es) within 3 weeks of the initiation of therapy as monitored by computerized tomography. Seventeen patients were cured, three patients died due to causes unrelated to their infection. One patient was reoperated since no clear improvement either clinically or radiologically was observed 18 days after the first operation. Side effects of sulbactam/ampicillin were minor and transient. Results obtained in this study indicate that sulbactam/ampicillin can be used in the treatment of intracranial abscesses, alone or with surgical intervention.

Adolescent↗
PubMed1993

Brucellosis of the spine.

The spinal form of brucellosis is still a disabling disease in many countries outside North America and northern and central Europe. Fifteen consecutive cases of spinal brucellosis diagnosed and treated over a 20-year period were reviewed retrospectively. Six patients were farmers, while 10 patients had a history of ingestion of unpasteurized milk or other dairy products. A high index of suspicion is necessary for the diagnosis, since there are no pathognomonic signs or symptoms. Radiological assessment of the disease was reviewed and highlights in the differential diagnoses were stressed. The diagnosis was based on actual culture of Brucella bacilli in seven patients. The principal treatment of brucellosis of the spine is conservative, namely, immobilization and antimicrobial therapy. We have found both a combination of ofloxacin and rifampin and ofloxacin monotherapy efficient as the early regimens used in this series. Three patients had to undergo surgery, since a diagnosis could not be made in any other way.

Adolescent↗
PubMed1992

Meningiomas of the lateral ventricle. Report on six cases.

In this study 6 patients who had meningioma of the lateral ventricle are reviewed. The incidence is 1.8% of cases of meningiomas in our series. Microsurgical techniques were employed in all patients. There was no death and the follow-up period was between 5 months and 10 years. No recurrence was seen. Although the origin of these tumors is still not known, DUNN and KERNOHAN note that the choroid plexus has the potential for the production of meningothelial, fibrous, or mixed patterns. Our pathological results confirmed this suggestion.

Adult↗