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The aim of this study was to compare the effects of 3 different sedative-analgesic regimens in patients with intracranial mass lesions undergoing stereotactic brain biopsy. A 135 outpatients with American Society of Anesthesiologists I to II were divided into 3 groups: group A (n = 45) received a loading dose of IV alfentanil 7.5 microg/kg followed by infusion rate of 0.25 microg/kg/min; group F (n = 45) received a bolus dose of 1 microg/kg IV fentanyl and repeated as needed; and group R (n = 45) received infusion of 0.05 microg/kg/min remifentanil. Target level of sedation was 3 to 4 of the Ramsay Sedation Scale. Systolic and diastolic blood pressure, heart rate, respiratory rate, peripheric oxygen saturation (SpO2), and end-tidal carbon dioxide were recorded at different stages of the procedures. The patients in group F had significantly lower mean heart rate than those in groups A and R, but this was not in the limits of the bradycardia. The patients in group A had significantly lower mean SpO2 than those in the other groups, but mean SpO2 values did not drop below 94%. There were no significant differences in end-tidal carbon dioxide and respiratory rate values among the groups. Our results suggest that all 3 regimens have relatively similar hemodynamic and respiratory responses. The use of bolus fentanyl technique caused less hemodynamic stability. The continuous infusion technique of remifentanil or alfentanil provided better control on hemodynamic parameters.

The objective of this study was to investigate the diagnostic value of serum tau protein in determining the severity of traumatic brain injury in patients with mild traumatic brain injury (mTBI) and high-risk patients. Adult patients who presented to our emergency department (ED) with mTBI over 1 year were prospectively enrolled. Patients underwent cranial computed tomography (CT) and were subdivided into high- and low-risk groups, according to the probability of resultant intracranial injury. Serum tau levels of 60 patients and 20 healthy volunteers, who served as a control group, were measured. The mean age of the 60 patients (45 males, 15 females) was 32.5 years (range, 15-66 y). Mean Glasgow Coma Scale (GCS) score was 14+/-0.6. CT scans demonstrated intracranial injury in 11 patients (18.3%) and depressed fracture in 4 patients (6.7%). Serum tau levels of patients (188+/-210 pg/mL), compared with those of controls (86+/-48 pg/mL), were relatively higher; however, differences were not statistically significant (P=.445). Also, serum tau levels of high-risk patients (307+/-246 pg/mL) were significantly higher than those of low-risk patients (77+/-61 pg/mL) (P=.001). A total of 48 patients (80%) were accessible for follow-up after 6 months. Postconcussive syndrome was observed in 8 patients, 5 of whom had serum tau protein levels that were higher than those of the other 3 patients. However, no statistically significant difference was observed (P.05). Investigators of the present study noted that serum tau levels in patients with mTBI were increased. Therefore, it is believed that this biomarker may prove helpful in identifying high-risk patients with mTBI. However, additional studies are needed to establish the diagnostic value of serum tau in detecting traumatic brain injury in patients with mTBI.

Background. The purpose was to analyse the clinical and radiological findings, and management approaches used in 30 consecutive cases of traumatic epidural haematoma of nonarterial origin treated at one centre. Method. Medical records for 30 patients surgically treated for epidural haematoma of nonarterial origin between 1997 and 2003 were reviewed. Epidural haematoma of nonarterial origin was diagnosed based on computed tomography (CT) and the bleeding source was confirmed intra-operatively. Admission status, outcome, fracture location, haematoma location/size/volume, and additional intracranial pathology were among the data noted. Two groups were formed for analysis: venous sinus bleeding (group 1) and other venous sources (group 2). Findings. The 30 cases accounted for 25% of the total number of traumatic epidural haematomas (n = 120) treated during the same period. The epidural haematomas of nonarterial origin locations were transverse sigmoid sinus (n = 11; 36.7%), superior sagittal sinus (n = 6; 20%), venous lakes (n = 5; 16.6%), diploe (n = 5; 0.16%), arachnoid granulations (n = 2; 6.7%), petrosal sinus (n = 1; 3.3%). There were 12 postoperative complications in 9 patients: recurrence (n = 4; 13.3% of the 30 total), pneumonia (n = 4; 13.3%), meningitis (n = 2; 6.7%), hydrocephalus (n = 1; 3.3%) and subdural effusion (n = 1; 3.3%). All recurrence cases were re-explored. Six (20%) patients died. Glasgow Outcome Scale (GOS) scores (mean follow-up 13.3 +/- 7.8 months) revealed 22 (73.3%) patients with favourable results (GOS 4-5) and 8 (26.7%) had poor results (GOS 1-3). Conclusions. Cases of epidural haematoma of nonarterial origin differ from the more common arterial-origin epidural haematomas with respect to lesion location, surgical planning, postoperative complications, and outcome. Epidural haematoma of nonarterial origin should be suspected if preoperative CT shows a haematoma overlying a dural venous sinus or in the posterior fossa and convexity. The sinus-origin group had a high frequency of fractures which crossed the sinuses, and this might be diagnostically and surgically useful in such cases.

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.

Secondary insults occuring after injury have been prospectively assessed in seven head-injured patients who required intrahospital transfer to a computerized tomography unit for re-evaluation of their brain injury. During transportation the intracranial pressure, blood pressure. and arterial blood gases were monitored. A significant increase in intracranial pressure was observed during transport (p < 0.01). The conclusion is that patients should be ventilated and have appropriate sedation and analgesia. This could provide some protection against secondary insults.

Proton magnetic resonance spectroscopy (MRS) complements conventional methods used to differentiate intracranial cystic lesions. We report MRS findings of three cases that were diagnosed as pyogenic, tuberculous, and Cryptococcus abscesses before instituting any medical or surgical therapy. The pyogenic brain abscess had typical specific spectral findings (i.e., the demonstration of amino acids). Lactate and lipid peaks were visible in the tuberculous abscess. Cryptococcus neoformans can appear differently in different brain regions, which may lead to different spectral findings.

Serebral aspergilloz nadir bir durum olup konvansiyonel antifungal tedavilere genellikle kötü yanıt vermektedir. Bu raporda, 34 yaşında akut lenfoblastik lösemi tanısı olan bir erkek hastada agresif nörocerrahi, intrakaviter amfoterisin B tedavisi ve vorikonazol kombinasyonu ile başarıyla tedavi olan bir serebral aspergilloz olgusu sunulmuş ve nöroaspergillozun tedavisinde cerrahi tedavi, intrakaviter tedavi ve antifungal tedavinin rolleri tartışılmıştır. Amfoterisin B tedavisi altında dizartri ve sağ hemiparazi gelişen olgumuzda beyin manyetik rezonans görüntülemede sol paryeto-oksipital bölgede 7 cm çapında lezyon saptanmıştır. Tanı amaçlı yapılan cerrahi girişim aşırı kanama nedeniyle başarıyla gerçekleştirilememiştir. Lezyondan alınan aspirat örneğinin kültüründe Aspergillus flavus üremesi saptanmıştır. Tedavi kaspofungin ve vorikonazol kombinasyonu olarak değiştirilmiştir. Tedavi altında enfeksiyonun ilerleme göstermesi üzerine hastaya ikinci cerrahi girişim uygulanmış ve lezyonun boyutunda gerileme tespit edilmiştir. Cerrahi tedaviyi takiben vorikonazol ve kaspofungin kombinasyon tedavisine ek olarak intrakaviter amfoterisin B uygulaması yapılmıştır (0.3 mg/gün 15 gün). Kaspofungin tedavisine 42 gün devam edildikten sonra kesilmiştir. Vorikonazol tedavisine ise 100 gün devam edilmiştir. Bu dönemde beyindeki lezyon tama yakın düzelme göstermiştir. Ancak, hastanın takibi sırasında lösemi relapsı görülmüş ve kemoterapi sırasında aplazik dönemde gelişen nötropenik tiflitis tablosu ile hasta kaybedilmiştir. Serebral aspergillozlu olgularda erken dönemde radikal cerrahi uygulanması sonucunda daha iyi sonuçlar elde edildiği belirtilmektedir. Antifungal tedavide kullanılan ilaçların vorikonazolde olduğu gibi kan-beyin bariyerini geçebilme özelliğine sahip olması gerekmektedir. Tüm lezyonlar düzelinceye ve altta yatan predispozan faktörler geri dönünceye kadar tedaviye devam edilmelidir. Sonuç olarak, serebral aspergillozlu olgularda cerrahi girişim ve vorikonazol tedavisinin güvenilir ve etkin tedavi yaklaşımları olduğu düşünülmüştür. Cerebral aspergillosis is a rare condition that generally exhibits a poor response to conventional antifungal drugs. We report here a case of cerebral aspergillosis in a 34-years-old man with acute lymphoblastic leukaemia who was successfully treated with a combination of aggressive neurosurgery, intracavitary instillation of amphotericin B and voriconazole. We aimed to emphazise the roles of surgery, intracavitary therapy and antifungal therapy in the management of neuroaspergillosis. Under amphotericin-B therapy, the patient developed dysarthria and paralysis of the right side of his body. Brain magnetic resonance imaging demonstrated a lesion in the left parieto-occipital region, measuring 7 cm in the greatest dimension. Diagnostic surgery was interrupted due to abundant bleeding. The culture of the aspirate from the lesion yielded Aspergillus flavus. The therapy was switched to voriconazole and caspofungin combination. Due to disease progression during combination therapy, the patient had a second surgical resection resulting in a 75% reduction in lesion size. Following surgical intervention, intracavitary instillation of amphotericin B (0.3 mg/day for 15 days) was performed alongside with combination therapy (voriconazole and caspofungin). Caspofungin was stopped after 42 days, whereas the patient was continued on voriconazole for a total of 100 days. At this point, his brain lesion resolved almost completely. However, leukemia relapsed. The patient died during his treatment course because of neutropenic typhilitis occurring in the aplastic phase. It is stated that in patients with neuroaspergillosis radical neurosurgery leads to better outcomes if performed at an earlier stage. Antifungal treatment of cerebral aspergillosis requires that the drug must cross the blood brain barrier. Voriconazole has the ability to cross the blood brain barrier. The therapy should be prolonged beyond the resolution of all lesions and until reversal of the underlying predisposition. We conclude that the use of neurosurgery and voriconazole together appears to be a reliable and effective treatment modality in patients with cerebral aspergillosis.

OBJECTIVE:To evaluate the differences in spinal stability and stabilizing potential of instrumentation after cervical corpectomy and spondylectomy. METHODS: Seven human cadaveric specimens were tested: 1) intact; 2) after grafted C5 corpectomy and anterior C4-C6 plate; 3) after adding posterior C4-C6 screws/rods; 4) after extending posteriorly to C3-C7; 5) after grafted C5 spondylectomy, anterior C4-C6 plate, and posterior C4-C6 screws/rods; and 6) after extending posteriorly to C3-C7. Pure moments induced flexion, extension, lateral bending, and axial rotation; angular motion was recorded optically. RESULTS: After corpectomy, anterior plating alone reduced the angular range of motion to a mean of 30% of normal, whereas added posterior short- or long-segment hardware reduced range of motion significantly more (P < 0.003), to less than 5% of normal. Constructs with posterior rods spanning C3-C7 were stiffer than constructs with posterior rods spanning C4-C6 during flexion, extension, and lateral bending (P < 0.05), but not during axial rotation (P > 0.07). Combined anterior and C4-C6 posterior fixation exhibited greater stiffness after corpectomy than after spondylectomy during lateral bending (P = 0.019) and axial rotation (P = 0.001). Combined anterior and C3-C7 posterior fixation exhibited greater stiffness after corpectomy than after spondylectomy during extension (P = 0.030) and axial rotation (P = 0.0001). CONCLUSION: Circumferential fixation provides more stability than anterior instrumentation alone after cervical corpectomy. After corpectomy or spondylectomy, long circumferential instrumentation provides better stability than short circumferential fixation except during axial rotation. Circumferential fixation more effectively prevents axial rotation after corpectomy than after spondylectomy. Synthes Spine

The objective of this study was to evaluate the role of phase-contrast cine magnetic resonance imaging (PC-MRI) in detecting possible communications between intraventricular arachnoid cysts (IV-ACs) and cerebrospinal fluid (CSF) spaces based on MR cisternography (MRC) comparison. Twenty-one patients with IV-AC were examined by PC-MRI and MRC. In order to determine the communication of IVAC with its neighbouring CSF spaces, PC-MRI was employed. The communication of IV-ACs with the ventricular system was examined on at least two anatomic planes. Precontrast images and PC-MRI were followed by the intrathecal administration of 0.5-1 ml gadopentetate dimeglumine. Early and delayed MRC were then carried out. Results of PC-MRI were compared with findings of MRC (McNemar's test). In seven IV-ACs, no communication was detected by PC-MRI. In 14 IVACs, a pulsatile CSF flow into the IV-ACs was observed. All the IV-ACs, which have been determined as non-communicating (NC) on the PC-MRI, showed NC character on MRC as well. Six cases suggesting a communication on PC-MRI showed no communication on MRC. MRC revealed eight communicating (38%) and 13 NC (62%) IV-ACs among a total of 21 cases. The sensitivity and specificity of PC-MRI imaging in demonstrating the communication between the IV-ACs and the CSF were 100% and 54%, respectively. PC-MRI is an effective method for evaluating NC IV-ACs. In order to decide about the management of IV-ACs, which are communicating according to the PC-MRI, the results should be confirmed with MRC if suspected jet flow is depicted.

Several genes encoding for different cytokines may play crucial roles in host susceptibility to tuberculosis (TB), since the cytokine production capacity varies among individuals and depends on the cytokine gene polymorphism. The association of the cytokine gene polymorphisms with the development of TB was investigated in this study. DNA samples were obtained from a Turkish population of 81 patients with the different clinical forms of TB, and 50 healthy control subjects. All genotyping (IL-6, IL-10, IFN-gamma, TGF-beta and TNF-alpha) experiments were performed using sequence-specific primers PCR (PCR-SSP). Analysis of allete frequencies showed that IL-10 - 1082 G allele frequency was significantly more common in TB patients than healthy controls (37.7% vs 23.0%, p: 0.0 14). No statistically significant differences were observed betwe\en the different clinical forms of the disease. These results suggest that the polymorphisms in IL-10 gene may affect susceptibility to TB and increase risk of developing the disease. To confirm the biological significance of our results, further studies should be performed on other population groups. (c) 2006 Elsevier Ltd. All rights reserved.

Background: As in all diffuse gliomas, recurrence is an inherent feature of oligodendrogliomas, either as the same or higher grade neoplasm at the primary site. The rate of remote recurrence after surgery for the primary tumor cannot be estimated from the scarce literature, but delayed treatment of the primary tumor and genetic alterations may be associated with this phenomenon. Case Description: A 40-year-old man presented with generalized seizures. A magnetic resonance imaging scan disclosed a right frontal mass lesion showing features of a low-grade glioma for which he refused any treatment. Seven months after diagnosis upon uncontrollable seizures, he underwent a stereotactic biopsy, which was followed by a right frontal craniotomy, both of which confirmed the lesion as a grade 2 oligodendroglioma. Six months after surgery, the patient presented with a left frontal lobe GBM without evidence of recurrence at the primary site. The genetic analysis of the primary and recurrent tumors showed trisomy 7, monosomy 10, but not 1p or 19q deletions, which have been proposed as markers for favorable prognosis. Conclusion: Recurrence of a frontal lobe oligodendroglioma remote from the primary site as a GBM is a rare occurrence. Single-cell invasion across the corpus callosum with subsequent or simultaneous malignant degeneration into a secondary GBM is the likely mechanism. As the genetic analysis suggests, conversion of oligodendroglioma to GBM may be associated with gain of chromosome 7, loss of chromosome 10, and other genetic markers that may represent late events in the oncogenesis of oligodendroglial tumors.

Introduction To investigate the contribution of perfusion-weighted MRI to the differentiation of meningiomas with atypical conventional MRI findings from intraaxial tumors. Methods We retrospectively analyzed 54 meningiomas, 12 glioblastomas and 13 solitary metastases. We detected 6 meningiomas with atypical features on conventional MRI resembling intraaxial tumors. The regional cerebral blood flow (rCBV) ratios of all tumors were calculated via perfusion-weighted MRI. The signal intensity-time curves were plotted and three different curve patterns were observed. The type 1 curve resembled normal brain parenchyma or the postenhancement part was minimally below the baseline, the type 2 curve was similar to the type 1 curve but with the postenhancement part above the baseline, and the type 3 curve had the postenhancement part below the baseline accompanied by widening of the curve. Student's t-test was used for statistical analysis. Results On CBV images meningiomas were hypervascular and the mean rCBV ratio was 10.58 +/- 2.00. For glioblastomas and metastatic lesions, the rCBV ratios were 5.02 +/- 1.40 and 4.68 +/- 1.54, respectively. There was a statistically significant difference in rCBV ratios between meningiomas and glioblastomas and metastases (P < 0.001). Only one of the meningiomas displayed a type 2 curve while five showed a type 3 curve. Glioblastomas and metastases displayed either a type 1 or a type 2 curve. None of the meningiomas showed a type 1 curve and none of the glioblastomas or metastases showed a type 3 curve. Conclusion Differentiating meningiomas with atypical conventional MRI findings from malignant intraaxial tumors can be difficult. Calculation of rCBV ratios and construction of signal intensity-time curves may contribute to the differentiation of meningiomas from intraaxial tumors.

Background: Glutamergic excitotoxicity has been shown to play a deleterious role in the pathophysiology of ischemic spinal cord injury (ISCI). The aim of this study was to investigate the neuroprotective effect of a single dose of MK-801, an antiexcitotoxic drug, in a rat model of ISCI. Methods: Ischemic spinal cord injury was induced for 17 minutes in Sprague-Dawley rats using direct aortic arch, just proximal to the left common carotid artery, plus left subclavian artery cross-clamping through a left-sided limited thoracotomy. Study groups were as follows: control group (n = 8) receiving only vehicle and experimental group (n = 8) receiving a single dose of MK-801 (1 mg/kg IV) 10 minutes before aortic clamping. Neurological examination was performed at 6 hours, 24 hours, and daily up to 96 hours. Rats were sacrificed at 96 hours, and spinal cords were removed for histopathology. Results: All the control rats had severe permanent neurological deficits after ISCI, whereas the MK-801-treated rats had statistically (P

A 53-year-old woman presented with a rare case of cavernous hemangioma of the frontal bone manifesting as right frontal stabbing headache and local swelling. Computed tomography revealed an extensive, well-defined, radiolucent, osteolytic lesion in the right frontal bone. The inner and outer tables of the skull were eroded and the lesion had compressed the brain parenchyma. Right frontal craniotomy was performed, and the lesion with a 1 cm-wide margin of surrounding uninvolved bone was removed. The defect was reconstructed with titanium mesh. The patient did well after the operation. The cosmetic results were satisfactory and follow up at 6 months post-surgery revealed no recurrence.

Background: Numerous experimental and clinical studies have shown that intrastriatal fetal mesencephalic grafts grow, survive, and reinnervate host brain tissue, resulting in partial recovery of motor deficits. In addition, pharmacological evidence indicates that these grafts increase dopamine secretion in lesioned brain. However, to date, no grafting method has completely restored the nigrostriatal pathway, and there is no consensus on optimal graft numbers or locations. This study compared outcomes with multiple striatal grafts vs a single intranigral graft in a rat model of Parkinson disease. Methods: Forty-one female Wistar rats weighing 200 to 250 g were used. First, baseline rotational behavior testing with amphetamine injection was done to identify each animal's dominant nigrostriatal pathway (left vs right hemisphere). Some rats then received a unilateral intranigral injection of 6-hydroxydopamine (4 mu L [8 mu g]) to produce the Parkinson model lesion, and rotational testing was repeated. One group of the lesioned rats received a single intranigral injection of suspended fetal ventral mesencephalic cells (n = 11), and another received multiple intrastriatal grafts of the same type (n = 11). Results: Both grafted groups showed significant improvement on rotational testing with amphetamine and apomorphine at 6 weeks "postgrafting" (P

OBJECTIVE: This study looked at the effects of single and multiple small subarachnoid hemorrhage (SAH) caused by puncturing a small branch of the basilar artery in rats. METHODS: Rats were subjected to single SAH (n = 21), multiple SAH (n = 21), sham operation (n = 21), or no procedures (control group, n = 7). SAH was induced in rats by tranclival puncture of a small branch of the basilar artery. In the multiple-SAH hemorrhage-groups, three small hemorrhages were produced in the same artery at three different times (initial and 24 and 48 h). In the single-SAH groups, one small hemorrhage was produced. Measurements of local cerebral blood flow (LCBF) were made at the initial SAH procedure and at three different time points. Seven animals from each general grouping were killed on Days 4, 10, and 14 (after LCBF was measured). Three different levels of the basilar artery were examined in each animal. Luminal area and arterial wall thickness were measured, and the findings were compared with control and corresponding sham groups findings. RESULTS: LCBF dropped dramatically (by 40%) immediately after SAH and reached levels near baseline within 15 minutes (n = 42) (P < 0.001). LCBF continued to drop after initial SAH and reached the lowest level on Day 10 (P < 0.001) or Day 14 (P < 0.05). Significant luminal narrowing (P < 0.01) and thickening of the arterial wall (P < 0.01) were observed in both groups. CONCLUSION: Single or multiple small SAHs produced by puncturing the basilar artery in the rat cause similar acute and chronic cerebral vasospasm.

Twenty-four adult male Wistar rats, weighing 220 to 290 g, were anesthetized with 30 mg/kg intraperitoneal sodium thiopental, then underwent a tracheostomy. After diffuse impact-acceleration brain injury (BI) was induced, each rat was paralyzed and mechanically ventilated with 30% O-2 in nitrous oxide (N2O). The rats were assigned randomly to two groups, each of which received one of the two volatile anesthetic agents, sevoflurane or isoflurane. The anesthetics were administered at 0.5, 0.75, 1.0, and 1.25 minimal alveolar concentration (MAC) for 30 minutes each, respectively, and anesthesia was maintained at 0.75 MAC during the last hour of the study period. Intracranial pressure (ICP), mean arterial pressure (MAP), rectal and intrahemispheric temperatures, and end-tidal volatile anesthetic concentrations were monitored continuously throughout the 3 hours, with measurements recorded every 15 minutes. At baseline, there: were no significant differences between the two groups regarding the monitored physiologic values. In the sevoflurane group, MAP fell significantly after 45 minutes, and a similar change was observed in the isoflurane group after 30 minutes (P < .05, P < .01, and P < .001. respectively). Intracranial pressure increased significantly at 45 minutes in the sevoflurane group (P < .01) and remained elevated from 60 minutes until the end of the study period (P < .01. P < .001). Although ICP increased in the isoflurane group, the change was not significant. Cerebral perfusion pressure (CPP) decreased in parallel with MAP, with the reduction in the sevoflurane group being more: pronounced than that in the isoflurane group. The results demonstrated that, under the conditions of diffuse BI, animals that were anesthetized with sevoflurane had higher ICP and lower CPP levels than those anesthetized with isoflurane.

A very rare case of a pontine hydatid cyst is reported. It was diagnosed preoperatively on the basis of magnetic resonance imaging findings. The patient was operated on in the sitting position. Total excision of the cyst using the Dowling technique and gravity effect was performed through the floor of the fourth ventricle. The patient was discharged without extra neurological sequel. The significance of an accurate preoperative diagnosis, surgical approaches and technique in the management of this pathology is discussed.

Adult male Sprague-Dawley rats (n = 87) weighing 350-400 g were used for studying the anatomy of the horizontal segment of middle cerebral artery and infarct area after occlusion of the artery. In the experimental group (n = 27) middle cerebral artery was coagulated 3-4 mm length from the origin of the lateral striate arteries to the inferior cerebral vein and divided. Control rats (n = 20) had all the surgical procedures except occlusion. Another group of rats (n = 40) were used to determine the anatomical variations of middle cerebral artery after intracarotid carbon black injection. Five major patterns of middle cerebral artery were observed and two of them were major and constituted 92.5% of rats. Twenty-four hours after middle cerebral artery occlusion, all animals were neurologically evaluated. On the third day after occlusion the brains were stained with 2%, 2,3,5-triphenyltetrozolium chloride. The area of infarction was assessed by computerized analysis method. In our study after determining the variations of the middle cerebral artery and its branches in our strain of rats, we were able to achieve 92.5% grade III and IV infarcted area.

BACKGROUND Cauda equina syndrome occurring as a result of spontaneous spinal subarachnoid hemorrhage (SAH) from a spinal tumor is reported to be rare. CASE DESCRIPTION A 28-year-old woman presented at our clinic with a history of severe back pain for 10 days, progressive paraparesis, and urinary retention. Her physical examination revealed a mass located intradurally at the level of L1-2 and a massive SAH. An L1-L2, laminectomy and a hemilaminectomy from D9 to D12 were performed and the SAH was evacuated and the cord was decompressed. CONCLUSION At the first year follow-up, her restricted dorsal and plantar flexion continued. Post-gadolinium magnetic resonance imaging revealed no mass.

The trigeminocardiac reflex (TCR) is manifested by the sudden development of cardiac dysrhythmia, bradycardia, arterial hypotension, apnea, and gastric hypermotility that occurs especially during ocular and craniofacial surgery and tumor resection at the cerebellopontine angle (CPA). A 58-year-old man who presented with headache, hearing loss, and vertigo was admitted to the hospital. A cerebral magnetic resonance imaging revealed a tumor with a diameter of 4 × 3 cm at the right CPA. His medical history was unremarkable. All preoperative tests were normal. The patient was premedicated with midazolam at the operating room. Anesthesia was induced with intravenous propofol, fentanyl, lidocaine, and vecuronium, and maintained with sevoflurane in 50% air and oxygen. Monitors consisted of electrocardiogram, pulse oximetry, radial artery catheter, central venous pressure catheter (CVC), capnograph, precordial doppler, neuromuscular stimulator, and urinary catheter. After the patient was placed in the sitting position, his hemodynamic variables and arterial blood gas analysis were normal. During tumor dissection under the trigeminal nerve, a sudden asystole developed with a loss of sinus rhythm on the electrocardiogram, invasive blood pressure wave, and the doppler sound. The surgical team was informed, and manipulation was halted. The surgical area was irrigated with saline, inspiratory oxygen flow was increased to 100%, and the patient's position was changed to lower the head to heart level and to left lateral decubitus. No air bubbles aspirated from the CVC. Atropine (3 mg, intravenous) bolus was administered. When no cardiac rhythm was seen within 60 seconds, a precordial thump was applied, and thoracal compression was started. A return of normal sinus rhythm was observed within 20 seconds. The surgical procedure was resumed. Recovery period from anesthesia was uneventful.

Bone flaps are occasionally not replaced because of brain swelling or for other reasons. Various methods for preserving the free bone flaps have been described. Reimplantation of a free bone flap after a period of preservation outside the body, however, may be complicated by infection, and facilities for proper preservation under sterile conditions may not be available. We present a new technique for preserving the bone flap under the scalp until brain swelling has resolved. The bone flap is reimplanted 12–48 days later. No serious complications related to this technique have been encountered in the 37 patients in which it was used.

Effects of fetal substantia nigra grafts on the dopamine receptors in the corpus striatum in rats were investigated after the destruction of the nigrostriatal dopaminergic pathways with intraventricular 6-hy-droxydopamine injections. The expected dopamine receptor denervation supersensitivity was demonstrated by a 53.7 % increase of [3H] spiroperidol binding in rats with sham grafts compared with normal control-group rats. In contrast, rats with grafts showed a significant reduction of supersensitivity, with a 25 % decrease in binding to the graft-bearing caudate when compared with the sham-graft group. A non-significant 15% decrease in binding on the nongrafted side was also observed. The fetal substantia nigra grafts thus reduced the denervation supersensitivity toward a normal level.

The effects of neuronotrophic factors (NFs) on adult adrenal medulla grafts transplanted into the rat caudate nucleus after the destruction of the nigrostriatal dopaminergic pathways were investigated. Two months after implantation, all of the adrenal medulla grafts treated with NFs, but only 45% of the untreated grafts, had survived. The levels of tyrosine hydroxylase activity in the caudate nucleus however, were not significantly different between the sham-operated control and either NF-treated or untreated grafted groups. These results indicate that treatment with NFs significantly enhances the survival rate of the grafts.