Concurrent presence of diabetes affects the GLUT3 programming of glucose metabolism in glioblastoma

OBJECTIVE

Diabetes mellitus (DM)-mediated impaired glucose metabolism increase in the glioblastoma (GB) risk by inducing hyperglycemia and hyperinsulinemia. An integral membrane transport protein, glucose transporter 3 (GLUT3) facilitates glucose transport into GB tumor cells. We aimed to explore the regulation of GLUT3 in GB tumors of patients who were concurrently diagnosed with DM.

PATIENTS AND METHODS

Formalin-fixed paraffin-embedded (FFPE) tumor samples were collected from 93 GB patients and retrospectively analyzed. Of the total, 15 patients were concurrently diagnosed with DM (GB-DM). The role of GLUT3 in tumor aggressiveness was evaluated by analyzing its correlation with Ki67, P53 expression, MALAT1 expression, and peripheral blood hemoglobin A1C (HbA1c) level. T98G cells were treated with empagliflozin and metformin to modulate GLUT3. The RNA expression of GLUT3, SOX2, and MALAT1 was analyzed by real-time qPCR. The lactate levels of T98G cells were measured by Cobas c502 analyzer. A scratch wound assay was performed to investigate the migration rate of T98G cells.

RESULTS

GLUT3 expression was lower in GB-DM tumors than in GB-only tumors. In GB-DM, the expression of tumoral GLUT3 and peripheral blood glycated hemoglobin (HbA1c) levels were negatively correlated with P53 and Ki67. A decreased GLUT3 shortened the disease-free survival duration in GB-DM patients. Empagliflozin reduced GLUT3, while metformin-induced GLUT3 in T98G cells. The empagliflozin-mediated GLUT3 suppression induced SOX2 and MALAT1 expressions and influenced the migration capacity of T98G cells.

CONCLUSIONS

Our findings suggest that the low GLUT3 expression of the tumors of GB-DM patients may induce the production of adenosine triphosphate (ATP) from cellular energy sources other than glucose metabolism. However, further studies are warranted to confirm these results.

Oleuropein modulates glioblastoma miRNA pattern different from Olea europaea leaf extract

Glioblastoma (GBM) is the most prevalent and deadliest subtype of glioma. Despite current innovations in existing therapeutic modalities, GBM remains incurable, and alternative therapies are required. Previously, we demonstrated that Olea europaea leaf extract (OLE) kills GBM cells by modulating miR-181b, miR-137, miR-153 and Let-7d expression. However, although oleuropein (OL) is the main compound in OLE, its role in the antitumour effect of OLE remains unknown. This study determined the effect of OL on GBM cell line T98G and compared the results with our previous findings regarding the effect of OLE on the same cell line. The antiproliferative activity of OL and its effect on temozolomide (TMZ) response were tested inT98G cells using WST-1 assay. OL inhibition was evaluated using one-way analysis of variance with Tukey's post hoc test. The effect of OL on miR-181b, miR-137, miR-153 and Let-7d expression was assessed using quantitative reverse transcription polymerase chain reaction. Fold differences in expression between untreated, OL or OL + TMZ-treated samples were calculated using 2^-ΔCt method. Significance was evaluated using an independent sample t-test. Treatment with 277.5 and 555 µM OL resulted in 39.51% and 75.40% reductions in T98G cells within 24 h. Coadministration of 325 µM TMZ and 277.5 or 555 µM, OL caused 2.08- and 2.83-fold increases, respectively, in the therapeutic effect of TMZ. OL + TMZ significantly increased microRNA expression, particularly Let-7d, than OLE. In conclusion, OL has an antitumour effect on GBM cells mainly via regulation of Let-7d expression. The present results also indicate other minor compounds in OLE play important anticancer roles.

Relationship between programmed cell death-1 polymorphisms and clearance of hepatitis B virus

Programmed cell death-1 (PD-1) plays a critical role in regulating T-cell function during hepatitis B virus (HBV) infection. This study investigated the relationship between the polymorphisms of PD-1 gene and the susceptibility to HBV infection. Single nucleotide polymorphisms (SNPs) in PD-1 gene at positions +7146 G>A (guanine to adenine substitution) and +7209 C>T (cytosine to thymine substitution) were analysed using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method in 220 subjects with chronic hepatitis B infection and 165 spontaneous clearance of HBV subjects. However, no statistically significant differences were found in the genotype distributions of the PD-1 +7146 G>A and PD-1 +7209 C>T polymorphisms among chronic hepatitis B and spontaneous clearance subjects. According to stratified analyses, borderline significance was observed between PD-1 +7146 GA genotype and risk of HBV chronicity in the subgroup of male gender (OR = 1.88, 95% 0.95-3.71; P = 0.07). Our findings demonstrate for the first time that the PD-1 +7146 G>A and PD-1 +7209 C>T polymorphisms have not been any major role in genetic susceptibility to chronicity of HBV infection, at least in the population studied here. Independent studies are needed to validate our findings in a larger series, as well as in patients of different ethnic origins.

Assesment of perfusion in glial tumors with arterial spin labeling; comparison with dynamic susceptibility contrast method

PURPOSE

Arterial spin labeling perfusion imaging (ASL-PI) is a non-invasive perfusion imaging method that can be used for evaluation and quantification of cerebral blood flow (CBF). Aim of our study was to evaluating the efficiency of ASL in histopathological grade estimation of glial tumors and comparing findings with dynamic susceptibility contrast perfusion imaging (DSC-PI) method.

METHODS

This study involved 33 patients (20 high-grade and 13 low-grade gliomas). Multiphase multislice pulsed ASL MRI sequence and a first-passage gadopentetate dimeglumine T2*-weighted gradient-echo single-shot echo-planar sequence were acquired for all the patients. For each patient, perfusion relative signal intensity (rSI), CBF and relative CBF (rCBF) on ASL-PI and relative cerebral blood volume (rCBV) and relative cerebral blood flow (rCBF) values on DSC-PI were determined. The relative signal intensity of each tumor was determined as the maximal SI within the tumor divided by SI within symetric region in the contralateral hemisphere on ASL-PI. rCBV and rCBF were calculated by deconvolution of an arterial input function. Relative values of the lesions were obtained by dividing the values to the normal appearing symmetric region on the contralateral hemisphere. For statistical analysis, Mann-Whitney ranksum test was carried out. Receiver operating characteristic curve (ROC) analysis was performed to assess the relationship between the rCBF-ASL, rSI-ASL, rCBV and rCBF ratios and grade of gliomas. Their cut-off values permitting best discrimination was calculated. The correlation between rCBV, rCBF, rSI-ASL and rCBF-ASL and glioma grade was assessed using Spearman correlation analysis.

RESULTS

There was a statistically significant difference between low and high-grade tumors for all parameters. Correlation analyses revealed significant positive correlations between rCBV and rCBF-ASL (r=0.81, p<0.001). However correlation between rCBF and rCBF-ASL was weaker (r=0.64, p<0.001).

CONCLUSION

Arterial spin labeling is an employable imaging technique for evaluating tumor perfusion non-invasively and may be useful in differentiating high and low grade gliomas.

The immunohistochemical expression of c-Met is an independent predictor of survival in patients with glioblastoma multiforme

BACKGROUND AND AIMS

Because the outcome of glioblastoma multiforme (GBM) remains dismal, there is an urgent need for a better molecular characterization of this malignancy. The aim of this prospective study was to investigate the prognostic impact of the expression of c-mesenchymal-epithelial transition (c-Met) a receptor tyrosine kinase implicated in expression growth, survival, motility/migration, and invasion in GMB patients managed according to the established diagnostic and therapeutic protocols.

METHODS

Between May 2003 and March 2011, a total of 69 patients (33 males and 36 females; mean age: 52.2 ± 12.9 years, age range: 23-81 years) referred to our Department for the surgical removal of GBM were evaluated immunohistochemically for c-Met expression. Progression-free survival (PFS) and overall survival (OS) served as the main outcome measures.

RESULTS

Compared with c-Met- subjects (n = 38), c-Met+ subjects (n = 31) had both a significantly lower OS (15.3 ± 2.3 vs. 22.6 ± 2.5 months, respectively, p < 0.01) and PFS (12.3 ± 2.1 vs. 19.1 ± 2.6 months, respectively, p < 0.05). After allowance for potential confounders, multivariate Cox regression analysis identified c-Met+ as an independent predictor of both OS (hazard ratio = 1.7; 95 % confidence interval = 1.2-1.9, p < 0.01) and PFS (hazard ratio = 1.6; 95 % confidence interval = 1.1-2.3, p < 0.05).

CONCLUSIONS

Our findings suggest that c-Met immunohistochemical expression is an independent predictor of outcomes in patients with GBM treated by standard of care.

A functional polymorphism in pre-microRNA-196a-2 contributes to the susceptibility of hepatocellular carcinoma in a Turkish population: a case-control study

MicroRNAs (miRNAs) are an abundant class of small nonprotein-coding RNAs with posttranscriptional regulatory functions as tumour suppressors and oncogenes. Aberrant expression and structural alteration of miRNAs are thought to participate in tumourigenesis and cancer development. It has been suggested that the presence of single-nucleotide polymorphisms in precursor miRNAs (pre-miRNAs) can alter miRNA processing, expression, and/or binding to target mRNA and represent another type of genetic variability that can contribute to the development of human cancers. Recent studies have indicated that the miR-196a-2 rs11614913 (C→T) polymorphism could alter mature miR-196a-2 expression and target mRNA binding. To determine the association of the miR-196a-2 rs11614913 polymorphism with the risk of hepatocellular carcinoma (HCC) development in a Turkish population, a hospital-based case-control study was designed consisting of 185 subjects with HCC and 185 cancer-free control subjects matched for age, gender, smoking and alcohol status. The genotype frequency of the miR-196a-2 rs11614913 polymorphism was determined by using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. Our data shows that the CC genotype of the miR-196a-2 rs11614913 polymorphism is associated with increased risk of HCC development in this Turkish population (OR = 2.41, 95% CI: 1.30-4.50, P = 0.005). Furthermore, according to stratified analysis, a significant association was observed between the homozygote CC genotype and HCC risk in the subgroups of male gender (OR = 3.12, 95% CI: 1.53-6.34, P = 0.002) and patients with hepatitis B virus (HBV)-related HCC (OR = 2.88, 95% CI: 1.33-6.22, P = 0.007). Because our results suggest for the first time that the miR-196a-2 rs11614913 polymorphism may be a genetic susceptibility factor for HCC (especially in the male gender and HBV-infected patients) in the Turkish population, further independent studies are required to validate our findings in a larger series, as well as in patients of different ethnic origins.

Relationship between functional polymorphism in the Aurora A gene and susceptibility of hepatocellular carcinoma

Aurora A is considered a potential cancer susceptibility gene owing to overexpression or amplification of Aurora A gene that causes centrosome dysfunction, chromosome instability, tumourigenic transformation and checkpoint abnormalities. Functional coding region polymorphism F31I in the Aurora A gene has recently been shown to be associated with several human cancers, but its association with hepatocellular carcinoma (HCC) has yet to be investigated. Genetic polymorphism of Aurora A was investigated in 128 confirmed subjects with HCC and 128 cancer-free control subjects matched on age, gender, smoking and alcohol consumption by using a polymerase chain reaction-restriction fragment length polymorphism assay. Allele and genotype associations of Aurora A F31I polymorphism with HCC susceptibility were observed in comparisons between the patient and control samples (respectively; P = 0.005, P = 0.012). The proportion of the genotypes containing I31 allele in patients with HCC (39.8%) was significantly higher than that in patients without HCC (22.7%) (P = 0.003). The distribution F31I genotype was significantly associated with increased risk of HCC (P = 0.003, odds ratio = 2.26, 95% confidence interval = 1.31-3.90 for FI + II genotypes vs FF genotype). Our results suggest for the first time that the Aurora A F31I polymorphism may be a genetic susceptibility factor for HCC.

Minimally invasive awake craniotomy using Steiner-Lindquist stereotactic laser guidance

INTRODUCTION

Awake craniotomy permits the continuous assessment of intraoperative neurological functions. In addition, stereotactic laser guidance aids in performing minimally invasive procedures related to the radical resection of lesions located in eloquent and non-eloquent brain regions.

METHODS

Between May 2000 and October 2006, 117 consecutive patients with various intracranial tumoral lesions underwent 141 resection procedures. The eloquent areas were determined with the aid of anatomic landmarks and/or functional MRI (fMRI) examinations. The resection of the lesions was performed under continuous neurological examination. In all cases, postoperative MRI was performed within 24-72 h.

RESULTS

Seventy-seven males and 40 females were included in this study. The mean age of the patients was 52.0+/-12.6 years. Most of the lesions were located within the parietal lobe. Of the lesions, 33 (23.4%) were located within the cortex, whereas 108 (76.5%) were subcortical. The most common pathologies were metastasis (70 cases) and glioblastome multiforme (27 cases). In 20 (14.2%) of the patients, fMRI was performed preoperatively. Of 21 patients with multiple lesions, 18 underwent 2 craniotomies and 3 underwent 3 craniotomies. The mean operation time was 72+/-0.3 min, and the mean hospital stay was 3.26+/-1.82 d. The average lesion size was 11.92+/-15.26 cm(3). In 7 cases (4.9%), the surgery caused either new neurological deficits or a worsening of the existing deficits; these deficits were permanent in 2 (1.4%) cases. One patient (0.7%) died due to the development of postoperative intracerebral hemorrhage.

CONCLUSIONS

Awake craniotomy with the aid of stereotactic laser guidance is a safe procedure that assists in performing minimally invasive resection of lesions in eloquent and non-eloquent brain regions. Although direct intraoperative stimulation was not performed, detection of the functioning areas of the brain with fMRI decreased additional postoperative neurological deficits. Overall, this method decreased the operation time and hospital stay.

Risk factors and complications of intracranial pressure monitoring with a fiberoptic device

We prospectively investigated the complications associated with intraparenchymal intracranial pressure (ICP) monitoring using the Camino intracranial pressure device. A fiberoptic ICP monitoring transducer was implanted in 631 patients. About half of the patients (n=303) also received an external ventricular drainage set (EVDS). The durations (mean+/-SD) of ICP monitoring in patients without and with an EVDS were 6.5+/-4.4 and 7.3+/-5.1 days, respectively. Infection occurred in 6 patients with only an ICP transducer (6/328, 1.8%) and 24 patients with an EVDS also (24/303, 7.9%). The duration of monitoring had no effect on infection, whereas the use of an EVDS for more than 9 days increased infection risk by 5.11 times. Other complications included transducer disconnection (2.37%), epidural hematoma (0.47%), contusion (0.47%), defective probe (0.31%), broken transducer (0.31%), dislocation of the fixation screw (0.15%), and intraparenchymal hematoma (0.15%). In conclusion, intraparenchymal ICP monitoring systems can be safely used in patients who either have, or are at risk of developing, increased ICP.

Dilatation of Virchow-Robin perivascular spaces: report of 3 cases with different localizations

We report on three different cases with Virchow-Robin spaces, including one with extreme widening causing hydrocephalus. In one patient we have performed neuroendoscopic cyst fenestration to resolve the problem.

Spinal dural arteriovenous fistula in a case with lipomyelodysplasia

Coexistence of a spinal dural arteriovenous fistula within a dysraphic spinal lesion is a very rare situation. We report a 40-year-old man who presented with low back pain and progressive paraparesis. MR images showed an intradural high signal intensity mass at the L2-L3 level containing irregular signal void structures. Spinal angiography revealed extradural arteriovenous fistula with three connections, drained by a tortuous perimedullary vein.

Functional MRI in Patients with Intracranial Lesions near Language Areas

We aimed to depict Broca's area and Wernicke's area by word generation and sentence formation paradigms in patients with various intracranial lesions adjacent to language areas using functional MRI technique and to evaluate the ability of functional MRI to lateralize the hemispheric dominance for language. Twenty-three right-handed patients were included in this study. Lesions were classified as low-grade glioma (n=8), high-grade glioma (n=9), metastasis (n=1), meningioma (n=1), arteriovenous malformation (n=2) and mesial temporal sclerosis (n=2). We performed blood-oxygenated-level-dependant functional MRI using a 1.5-T unit. Word generation and sentence formation tasks were used to activate language areas. Language areas were defined as Brodmann 44, 45 (Broca's area) and Brodmann 22 area (Wernicke's area). Laterality index was used to show the dominant hemisphere. Two poorly cooperative patients showed no activation and were excluded from the study. Broca's area was localized in 21 patients (100 %). Wernicke's area, on the other hand, could only be localized in eight of the 21 patients (38 %).The left hemisphere was dominant in 86% of patients while atypical language lateralization (right or bilateral) was demonstrated in 14% of the patients. Bilateral activation areas were shown in 10% of those patients while right cerebral hemisphere was dominant in 4% of the patients. Word generation and sentence formation tasks are especially helpful in localizing Broca's area. Wernicke's area could also be demonstrated in some of the cases. Functional MRI can be used as an important and useful means of demonstrating language areas in patients with lesions adjacent to those areas and depicting the hemispheric dominance.

Primary central nervous system lymphoma in a renal transplant recipient with Bardet-Biedl syndrome

Bardet-Biedl syndrome (BBS) is a rare autosomal recessive disorder. End-stage renal failure has been reported as the most frequent cause of death in this disorder. There are few reports of kidney transplantation in these patients. Renal transplant patients are known to be at increased risk for the development of malignancies. Although a few patients with BBS have been described to develop malignant disease, there was no previous association with lymphoma. We report a 20-year-old patient in whom primary central nervous system lymphoma was diagnosed 20 months after renal transplantation.

The effect of hair on infection after cranial surgery

OBJECTIVE

Reports of large series of patients who had undergone successful cranial neurosurgery without hair removal led part of our team to abandon the practice of shaving patients' heads pre-operatively. The aim of this study was to assess whether this change in routine, which was implemented in 1992, has affected the rate of postoperative infection in our cranial surgery patients.

METHODS

A group of patients whose heads were shaved pre-operatively was compared to a group whose hair was not shaved prior to cranial surgery. The latter patients had their hair washed with shampoo and 4% chlorhexidine within 24 hours of their operation. In the operating room, the surgical site was scrubbed for 8-10 minutes with 4% chlorhexidine diluted with water, and then cleansed with 10% povidone-iodine solution. Prophylactic antibiotics were administered for 3 days.

RESULTS

We performed 1,038 cranial procedures without hair removal. The procedures included craniotomy for tumour, trauma, aneurysm, other vascular lesions and intracerebral haemorrhage (n = 847), stereotactic biopsy (n = 90), stereotactic craniotomy (n = 34), ventriculoperitoneal shunt placement (n = 27), surgical treatment of infection with aspiration of brain abscess or resection of infected tissue (n = 14), microvascular decompression for trigeminal neuralgia or hemifacial spasm (n = 11), and other miscellaneous procedures (n = 15). We observed 13 postoperative wound infections (1.25%), including 9 deep (0.87%) and 4 superficial infections (0.39%). There was no significant difference between the rate of infection in patients whose heads were shaven (12/980) and the rate in those whose hair was spared (13/1038) (p > 0.05). In addition. there were no other problems related to the surgical preparation technique in the latter group.

CONCLUSION

Cranial surgery without hair removal is safe and does not increase the risk of surgical wound infection. Patients naturally prefer to keep their full head of hair. We believe that preoperative hair removal is not necessary in preparation for any type of cranial neurosurgery.

A case of primary spinal intramedullary lymphoma

A 41-year-old male presented to our clinic with a 1-month history of left hemiparesis. He had marked left arm weakness. The diagnostic work-up revealed an intramedullary mass at spinal level C2-4. Laminectomies were performed at C2-3-4 and the tumor was subtotally resected. Histological examination identified the mass as a non-Hodgkin's diffuse B-cell lymphoma. The patient was treated with corticosteroids, chemotherapy, and adjuvant radiotherapy. The residual tumor tissue had completely disappeared by 6 months of follow-up; however, the patient presented with intraventricular metastasis at 11 months postsurgery.

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.

Minimally invasive craniotomy using the Steiner-Lindquist stereotaxic guide

Thirty-three obscure intracranial lesions were located using the Steiner-Lindquist microsurgical stereotaxic guide and then surgically resected. Seventeen of the lesions were located in the parietal region, six in the frontal region, three in the parietooccipital region, three in the temporoparietal region, one in the thalamic region, one in the centrum semiovale, one in the brainstem, and one in the third ventricle. Twenty-three lesions were in subcortical or cortical locations. In 28 cases, the lesion was totally removed, while in 5 the lesion was subtotally resected. Pathological examinations confirmed glial tumor in eight patients, metastasis in seven, meningioma in two, cavernous angioma in eight, arteriovenous malformation (AVM) in four, hematoma in two, dysembryoblastic neuroepithelial tumor in one, and septum pellucidum cyst in one. Two patients developed transient complications postsurgery. Mean lesion size was 23 +/- 0.97 mm. The hospitalization period ranged from 1 to 6 days (mean 3.4 +/- 1.3 days). Surgeries were performed under general anesthesia, or under local anesthesia with the patient awake. The Steiner-Lindquist microsurgical stereotaxic guide is useful for pinpointing small lesions, especially those in the subcortical and deep areas. Knowing the precise location of the lesion facilitates removal through a small craniotomy incision. This minimally invasive procedure reduces the number of postoperative neurological complications, and also cuts costs by shortening the hospital stay.

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.

Spinal subarachnoid hemorrhage attributable to schwannoma of the cauda equina

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.

Complications of brain tissue pressure monitoring with a fiberoptic device

Seventy-five patients with intracranial hypertension whose Glasgow Coma Score (GCS) was 8 or below and in whom intracranial pressure (ICP) was monitored were examined for complications of this procedure. In 20 of the 75 patients we used only an intraparenchymal fiberoptic ICP monitoring transducer, while, in the remaining 55 patients, who required CSF drainage, a ventricular drainage set (VDS) was used in addition to ICP monitoring. The duration of monitoring with the ICP transducer alone was approximately 5.1+/-2.6 das (min. 1, max. 13) and that of ICP monitoring with VDS was 6.2+/-3.1 days (min. 1, max. 13). In 8 cases a total of 9 complications were experienced (12%). These complications were infection in 3 cases (4%), epidural hematoma in 2 cases (2.7%), disconnection in 2 cases (2.7%) and contusion in 2 cases (2.7%). Although none of the 44 patients who were monitored for less than 5 days experienced infection, 3 of the 31 patients monitored for longer than 5 days did experience infection (9.7%) (p<0.05). None of the 20 patients who underwent ICP monitoring only experienced infection. However, 3 of the 55 patients in whom the ventricular drainage set was implanted in addition to the transducer for ICP monitoring experienced infection (p<0.05). Owing to its minimally invasive nature, low complication rate, and accuracy in monitoring the parenchyma pressure, the Camino fiberoptic intraparenchymal monitor has become the system of choice in our clinic.

Secondary insults during intrahospital transport of neurosurgical intensive care patients

Secondary insults occurring 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.

Unilateral blindness due to patient positioning during cervical syringomyelia surgery: unilateral blindness after prone position

During spinal surgery using a horseshoe headrest with the patient in the prone position, the possibility of central retinal artery occlusion (CRAO) increases, and its cause can be attributed primarily to excessive extraocular pressure, a very rare complication. This report describes a case of CRAO, occurring in an adult, after cervical syringomyelia surgery in which a horseshoe headrest was used.

Postoperative hemodynamic and thermoregulatory consequences of intraoperative core hypothermia

STUDY OBJECTIVE

To evaluate the postoperative hemodynamic and thermoregulatory consequences of intraoperative core hypothermia.

DESIGN

Prospective, randomized clinical trial.

SETTING

Operating room and postanesthesia care unit of a university hospital.

PATIENTS

74 healthy, ASA status I, II, and III patients (average age 58 yrs) undergoing elective colon surgery.

INTERVENTIONS

Patients were randomly assigned to be kept normothermic or approximately 2.5 degrees C hypothermic during surgery. Anesthesia was maintained with isoflurane, nitrous oxide, and fentanyl. Postoperatively, surgical pain was treated with patient-controlled analgesia (PCA) opioid.

MEASUREMENTS AND MAIN RESULTS

An observer blinded to group assignment and core temperatures evaluated shivering, thermal comfort, surgical pain, heart rates (HRs), and blood pressures (BPs) during the first six postoperative hours. Morphometric characteristics, oxygen saturation, fluid balance, PCA-administered opioid, and visual analog pain scores were comparable in the two groups. Hypothermic patients felt uncomfortably cold during recovery, and their postoperative core temperatures remained significantly less than in the normothermic patients for more than four hours. Peripheral vasoconstriction and shivering were common in the hypothermic patients but rare in those kept normothermic. HRs and BPs were comparable in the two groups.

CONCLUSIONS

These data confirm that the effects of intraoperative hypothermia on postoperative HR and BP are modest in relatively young, generally healthy patients. In contrast, intraoperative hypothermia caused substantial postoperative thermal discomfort, and full recovery from hypothermia required many hours. Delayed return to care normothermia apparently resulted largely from postoperative thermoregulatory impairment.