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A Savas

Publications and source records attributed to A Savas.

18 recordsLinked to original sources
PubMed2003

Stereotactically-guided fourth ventriculo-peritoneal shunting for the isolated fourth ventricle.

The isolated fourth ventricle (IFV) develops in which obstruction to the out flow of cerebrospinal fluid from the choroid plexus of the fourth ventricle occurs rostrally and caudally. IFV has been a rare occurrence and is difficult to treat. We had an occasion to admit a 28-year-old female to our hospital due to hydrocephalus: she also had a history of meningitis a year ago. The patient was initially managed by a lateral ventriculo-peritoneal shunting procedure. Six months after the procedure the patient began to suffer from vomiting, nausea, and diplopia. CT and MRI scans demonstrated an isolated fourth ventricle enlargement; and thus, a fourth ventriculo-peritoneal shunting procedure was performed under stereotactic conditions. The authors present a case of an isolated fourth ventricle after lateral ventriculo-peritoneal shunting for hydrocephalus, which was treated with a stereotactically guided fourth ventriculo-peritoneal shunting procedure. The technique of this procedure is described below.

Adult↗
PubMed2002

Neurological function-based research.

Function of the nervous system has been the main domain of interest of an elite group of philosophers, scientists and physicians. This topic may only be understood within a historical perspective, since the progression of knowledge of the function of the nervous system has always paralleled the expansion of our understanding of the outer world and of biological organisms observed. However, data gained from functional experimental and clinical researches in neurosurgery, neurology and neuroscience constitute not only a traditional and historical accumulation of this knowledge but also serve as one of the most important aspects of experimental and clinical neuroscience in the future. This article summarizes the basic principles and methods used in neurological function-based research. In order to elucidate the topic, the text was practically divided into three main sections: (1) historical perspective regarding functional research models in clinical and experimental neuroscience; (2) neurological function-based clinical studies in humans; and (3) experimental research models on animals.

Animals↗
PubMed2002

CT-guided percutaneous selective cordotomy for treatment of intractable pain in patients with malignant pleural mesothelioma.

Malignant mesotheliomas are neoplasms that arise from mesothelial cells and cause intractable pain in the chest wall, usually located unilaterally. This local pain can be well controlled by computerized tomography (CT)-guided percutaneous cordotomy (PC). One hundred and fifty-three patients suffering from intractable pain due to malignancy were treated with CT-guided cordotomy between 1988 and 2001. Seventy of the 153 patients had pulmonary malignancy. Among these, 40 had bronchogenic carcinoma, 11 had Pancoast tumors and the remaining 19 had mesothelioma. The latter 19 cases with malignant mesothelioma suffering from unilateral pain were treated with CT-guided PC. In 18 cases, pain was controlled totally and, in one, partial pain control was obtained. Selective pain control was obtained in 15 cases, in whom narcotic drugs were discontinued postoperatively. Post-cordotomy dysesthesia was noted in only one case, and no complication or mortality was observed. In the treatment of intractable pain, CT-guided cordotomy is a perfect method in selected cases with malignancy. This is the most effective and suitable treatment modality for local pain due to malignant mesothelioma.

Adult↗
PubMed2001

Surgical treatment of intracranial cavernous angiomas.

We present a surgical series of 35 patients (25 males and 10 females) with histopathologically verified intracranial cavernous angiomas. The 35 malformations were located as follows: 21 were in the cerebral hemispheres; 4 in the lateral ventricles, 4 in the brain stem; and 6 in the cerebellum. Seizures and focal neurological deficits were the main clinical features observed in patients with intracranial cavernous angiomas. A number of these vascular malformations were misdiagnosed by computerized tomography. In the last 10 years, magnetic resonance imaging has been the most sensitive method for detecting these lesions. Thirty-five cavernous angiomas were treated surgically; in 33 patients a complete excision, and in 2 patients subtotal excision were obtained. One of the patients died one year after the operation. The overall outcome was good in all of the 34 remaining patients, resulting in improved seizure control or neurological deficit. The rationale for neurologic differential diagnosis and surgical treatment and follow up results are discussed.

Adolescent↗
PubMed2001

Chiari Type I malformation presenting as glossopharyngeal neuralgia: case report.

OBJECTIVE AND IMPORTANCE: Chiari Type I malformation is an important pathological state in which the brainstem is compressed by the cerebellar tonsil. We present a case of glossopharyngeal neuralgia caused by Chiari Type I malformation. CLINICAL PRESENTATION: A 50-year-old male patient was admitted with glossopharyngeal neuralgia. Magnetic resonance imaging studies revealed caudal displacement of the left cerebellar tonsil. INTERVENTION: Small occipital craniectomy and C1 laminectomy were performed. The left cerebellar tonsil was resected. CONCLUSION: This glossopharyngeal neuralgia was caused by compression of the lower cranial nerves and brainstem by the displaced left cerebellar tonsil. Decompression and pain relief were obtained with resection of the cerebellar tonsil. The patient was pain-free 30 weeks after the operation.

Arnold-Chiari Malformation↗
PubMed2001

Percutaneous controlled radiofrequency trigeminal rhizotomy for the treatment of idiopathic trigeminal neuralgia: 25-year experience with 1,600 patients.

OBJECTIVE: The objective of this study was to evaluate the effectiveness of percutaneous, controlled radiofrequency trigeminal rhizotomy (RF-TR). The outcome of 1,600 patients with idiopathic trigeminal neuralgia after RF-TR was analyzed after a follow-up period of 1 to 25 years. METHODS: A total of 1,600 patients with idiopathic trigeminal neuralgia underwent 2,138 percutaneous radiofrequency rhizotomy procedures between 1974 and 1999. Sixty-seven patients had bilateral idiopathic trigeminal neuralgia, and 36 of them were treated with bilateral RF-TR; 1,216 patients (76%) were successfully managed with a single procedure, and the remainder were treated with multiple procedures. Benzodiazepines and narcotic analgesics were used for anesthesia because patient cooperation during the procedures was essential so that the physician could create selective, controlled lesions. RESULTS: The average follow-up time was 68.1 +/- 66.4 months (range, 12-300 mo). Acute pain relief was accomplished in 97.6% of patients. Complete pain relief was achieved at 5 years in 57.7% of the patients who underwent a single procedure. Pain relief was reported in 92% of patients with a single procedure or with multiple procedures 5 years after the first rhizotomy was performed. At 10-year follow-up, 52.3% of the patients who underwent a single procedure and 94.2% of the patients who underwent multiple procedures had experienced pain relief; at 20-year follow-up, 41 and 100% of these patients, respectively, had experienced pain relief. No mortalities occurred. After the first procedure was performed, early pain recurrence (<6 mo) was observed in 123 patients (7.7%) and late pain recurrence was observed in 278 patients (17.4%). Complications included diminished corneal reflex in 91 patients (5.7%), masseter weakness and paralysis in 66 (4.1%), dysesthesia in 16 (1 %), anesthesia dolorosa in 12 (0.8%), keratitis in 10 (0.6%), and transient paralysis of Cranial Nerves III and VI in 12 (0.8%). Permanent Cranial Nerve VI palsy was observed in two patients, cerebrospinal fluid leakage in two, carotid-cavernous fistula in one, and aseptic meningitis in one. CONCLUSION: Percutaneous, controlled RF-TR represents a minimally invasive, low-risk technique with a high rate of efficacy. The procedure may safely be repeated if pain recurs.

Adolescent↗
PubMed2001

The effects of continuous and single-dose radiation on choline uptake in organotypic tissue slice cultures of rabbit hippocampus.

The objective of the present study was to determine the time-dependent course of choline uptake in mature organotypic slice cultures of rabbit hippocampal formation and to assess the effects of continuous and single high-dose irradiation on choline uptake in cultivated slices in vitro. Transverse slices of hippocampus were dynamically incubated in a cerebrospinal fluid-like culture medium for 72 h. To study the changes in choline uptake longitudinally, the slice cultures were processed with 0.1 microM [3H]-choline, and tritium accumulation was counted. Two different gamma irradiation sources (125I seeds and a clinical 60Co source) were used as representative models of interstitial radiosurgery and other radiosurgical techniques. A total dose of approximately 6000 cGy was delivered to the brain slices in one session or in a continuous, relatively low-dose rate fashion, and their effects on high-affinity choline uptake were examined. In another set of experiments with 125I, 5 microM hemicholinium-3 was used in choline uptake procedures as a competitive high-affinity choline uptake inhibitor. The results can be summarized as follows: (1) in the control group of the hippocampal tissue culture, there was a significant increase in tritium accumulation values from 0 to 48 h and a decrease thereafter; (2) continuous 125I irradiation caused a highly significant depression of the accumulation of tritium compared to that observed in the control group throughout its application for 72 h; (3) there was no significant change in the accumulation of tritium in the slices after single high-dose rate irradiation with a 60Co source; and (4) 5 microM hemicholinium significantly depressed the accumulation of tritium in both the control and the 125I-irradiated groups, and there was no longer a difference between 125I-irradiated and control groups when both groups were treated with hemicholinium. These results demonstrate that the delivery of continuous but relatively low-dose rate gamma irradiation is more efficacious than single high-dose external irradiation on high-affinity choline uptake in hippocampal nervous tissue. The results also indicate that continuous irradiation specifically affected the high-affinity energy-dependent choline uptake mechanism, whereas nonspecific choline uptake did not seem to be disturbed.

Acetylcholine↗
PubMed2000

Percutaneous controlled radiofrequency rhizotomy in the management of patients with trigeminal neuralgia due to multiple sclerosis.

Between the years 1974 and 1999, 1,672 patients with medically intractable trigeminal neuralgia (TN) were treated by percutaneous controlled radiofrequency (RF) rhizotomy by the senior author and co-workers at the Department of Neurosurgery, Ankara University School of Medicine. Sixteen hundred cases (95.7%) were found to have idiopathic TN, while 72 cases (4.3%) were classified as symptomatic. In the latter group, TN was found to be caused by multiple sclerosis (MS) in 17 cases (23.6%), one of whom had bilateral TN. All patients having TN with MS (17 cases) underwent percutaneous controlled radiofrequency rhizotomy (25 procedures) as the procedure of choice. The MS patients were followed for an average of 60 months (range: 6-141 months). Complete pain relief was achieved with a single procedure in 12 of the 17 MS cases (70.6%). Early (less than 2 weeks) pain recurrence was seen in two patients (11.8%), while the overall recurrence rate was 29.4%. A second procedure was required to control TN in three cases (17.6%), a third in one (5.9%), and twice for each side for the case with bilateral TN (5.9%). Pain was completely relieved in 14 cases (82.4%) with single or multiple RF rhizotomies. In three cases (17.6%), partial pain control was achieved with RF rhizotomy, and the patients continued to receive adjunctive medical therapy. No complications were observed. All 17 patients (100%) were classified to have done well with RF rhizotomy. Satisfactory results and good long-term pain control were obtained in patients having TN due to MS with percutaneous controlled RF rhizotomy. The authors propose that RF rhizotomy may be a safe and effective procedure in the neurosurgical armamentarium for the treatment of patients having TN due to MS.

Adult↗
PubMed2000

Fatal toxic effect of bleomycin on brain tissue after intracystic chemotherapy for a craniopharyngioma: case report.

OBJECTIVE AND IMPORTANCE: Craniopharyngiomas are benign neoplasms of epithelial origin that arise from the remnants of Rathke's pouch and are located in the sellar, parasellar, and third ventricular regions. Despite major advances in microsurgical techniques, total removal of these tumors is associated with a high risk of death, long-term endocrinological dependence, cognitive dysfunction, and behavioral disorders. For patients with monocystic craniopharyngiomas, encouraging postoperative survival rates and high rates of cyst regression after intracavitary administration of bleomycin have been reported. Moreover, only a few side effects have been reported for this treatment method. We report a patient with a cystic craniopharyngioma who was treated using intracavitary bleomycin administration and died as a result of the direct toxic effects of bleomycin on deep brain structures and the brainstem. CLINICAL PRESENTATION AND INTERVENTION: A 47-year-old woman with a cystic craniopharyngioma underwent stereotactic insertion of a catheter attached to a subcutaneous reservoir. Five months after the procedure, positive-contrast computed tomographic cystography was performed to confirm the absence of fluid leakage. Daily intracavitary injections of bleomycin were administered through the reservoir into the cyst, until a total dose of 56 mg had been administered in 8 days. After the treatment, the cystic cavity regressed but the patient exhibited neurological deterioration; magnetic resonance imaging scans revealed diffuse edema in the diencephalon and brainstem. The patient died 45 days after completion of the treatment. CONCLUSION: Intracavitary administration of bleomycin is not a treatment protocol without risks or side effects, even if there is no fluid leakage into the cerebrospinal fluid. Although this is known to be an effective treatment for cystic craniopharyngiomas, previous reports cannot be used to establish a standard treatment method, and more research is needed to yield a safer effective protocol.

Antimetabolites, Antineoplastic↗
PubMed1999

Differential diagnosis of idiopathic inflammatory trigeminal sensory neuropathy from neuroma with a biopsy: case report.

OBJECTIVE AND IMPORTANCE: Idiopathic inflammatory trigeminal sensory neuropathy (IITSN) is a disorder with the dominant clinical features of trigeminal sensory disturbance; this idiopathic condition follows a benign course in most cases. Recent reports have shown that transient abnormalities, which may mimic those of trigeminal neuromas, can be observed in magnetic resonance imaging scans. Presented here is a case of IITSN that was diagnosed, with cytological and histopathological verification, during the active inflammatory phase of the disease (the first such attempt, to our knowledge). CLINICAL PRESENTATION: A 20-year-old female patient was referred to our hospital with a 2-month history of numbness of the left side of her face, headache, and hemifacial pain attacks. Cranial magnetic resonance imaging scans revealed a mass above and below the foramen ovale, extending into the cavernous sinus. INTERVENTION: A percutaneous biopsy procedure through the foramen ovale was performed; the pathological examination revealed lymphocytes, macrophages, and endothelial cells but no evidence of neoplastic cells. A few days later, the patient was surgically treated using a cranial base approach, the gasserian ganglion was exposed, and the lesion was removed. Pathological examination of the specimens revealed inflammatory changes and fibrosis of the nerve fibers and ganglion cells. Disruption of the myelin around the nerve bundles was detected. Therefore, IITSN was pathologically confirmed during the early stage of the disease. During 3 months of follow-up monitoring, the patient experienced no serious clinical problems. CONCLUSION: IITSN should be suspected in cases of tumors involving the cavernous sinus, and a percutaneous biopsy through the foramen ovale should be performed as part of the differential diagnosis in such cases. This procedure might obviate unnecessary aggressive surgery. In the current case, no neoplastic cells were observed during the examination; only lymphocytes, macrophages, and endothelial cells were observed, on a background of erythrocytes. Lymphocyte-dominant inflammatory infiltration, fibrotic changes, and demyelinization are cardinal histopathological findings observed during the active phase of IITSN.

Adult↗
PubMed1998

Stem cell factor (SCF) levels in newborns.

We studied Stem cell factor (SCF) levels in 15 mother-newborn pairs, 15 healthy adult controls, and 16 newborn with bacterial sepsis. SCF levels were also determined in six newborns with sepsis before and after completion of treatment. SCF levels (pg/mL) were found to be 2141 +/- 529 in cord blood, 1385 +/- 314 in mothers, 1546 +/- 443 in healthy adult controls, and 1742 +/- 655 in septic newborns. Cord blood SCF levels were significantly higher than their mothers' and healthy controls (p < 0.05). There were no differences in SCF levels between mothers and healthy adult controls. No correlation was found between the SCF levels and absolute neutrophil counts. There were no differences in SCF levels between the before and after treatment levels in six newborn with sepsis. In conclusion, our study suggests that SCF levels were increased in cord blood, and this increase is not a reflection of mothers' levels. SCF levels do not show significant changes during sepsis in newborns.

Adult↗
PubMed1998

Computed tomography-guided trigeminal tractotomy-nucleotomy in the management of vagoglossopharyngeal and geniculate neuralgias.

OBJECTIVE: Vagoglossopharyngeal and geniculate neuralgias are less frequently seen types of cranial neuralgias. Their causes and symptomatology are similar to those of trigeminal neuralgia; however, the complex anatomic relationship between the intermedius, vagal, and glossopharyngeal nerves leads to difficulties in the diagnosis and management of neuralgias originating from these cranial nerves. Numerous procedures have been used to treat intractable neuralgias of the VIIth, IXth, and Xth cranial nerves: 1) extracranial sectioning of the cranial nerves, 2) percutaneous thermal rhizotomy, 3) intracranial glossopharyngeal and vagal rhizotomies, 4) microvascular decompression, and 5) percutaneous trigeminal tractotomy-nucleotomy (TR-NC) or nucleus caudalis dorsal root entry zone operation. We propose that computer-guided TR-NC may be the first-choice operation for patients with glossopharyngeal, vagal, or geniculate neuralgia. PATIENTS AND METHODS: Nine patients suffering from idiopathic vagoglossopharyngeal neuralgia (six patients) and geniculate neuralgia (three patients) were managed at our clinic. Computed tomography-guided percutaneous trigeminal TR-NC was performed for these nine patients. RESULTS: Excellent (six patients) or good (three patients) pain control was obtained in each patient. Complications included temporary ataxia in two patients after TR-NC. CONCLUSION: The risk:benefit ratio should be evaluated individually to select the appropriate treatment procedure for patients with vagoglossopharyngeal and geniculate neuralgias. Computed tomography-guided percutaneous TR-NC is an effective and minimally invasive procedure for such patients.

Adult↗
PubMed1991

A simple method for reducing autotomy in rats after peripheral nerve lesions.

Experiments using peripheral nerve lesions (crush or transection) in rats to study repair processes are hampered by the tendency for the animals to attack the limb in which the peripheral nerves are damaged (autotomy). In this paper we describe a simple method which significantly reduces the incidence of autotomy after peripheral nerve lesions. The method consists of painting the hind paws of operated rats with a commercially available non-toxic lotion, which is used to discourage nail-biting and thumb-sucking in humans. Although the method is not absolute, it was extremely beneficial in our experiments, since the number of animals that had to be taken out of the experiment due to severe autotomy was greatly reduced. We believe that this method may prove to be as beneficial to other investigators who are using experimental peripheral nerve lesions to study the regenerative aspects of the nervous system.

Animals↗