Irrigation can cause prolonged intracranial pressure elevations during endoscopic treatment of intraventricular haematomas.

BACKGROUND: Irrigation may elevate the intracranial pressure (ICP) during neuroendoscopic procedures. It is unlikely that rinsing the ventricles during routine endoscopic ventriculostomy causes persistent neurological impairment or damage, but procedures such as the endoscopic evacuation of intraventricular haematomas (IVH) are performed in patients who may be prone to elevated ICP. We report a series of such patients in which we measured the ICP intraoperatively. METHOD: The charts and intraoperative ICP recording protocols of 22 patients were analysed for ICP elevations of more than 30 seconds. The measurements were performed remote from the endoscope using intraventricular catheters in 20 cases and epidural probes in 2 cases. These had been placed before the endoscopic operation for the purpose of monitoring unconscious patients or definitively diagnosing hydrocephalus. Thirteen patients suffered from intraventricular haemorrhages. Nine patients had an occlusive hydrocephalus without intraventricular blood. FINDINGS: Intraoperatively, at least one episode of ICP exceeding 30 mmHg was observed in all of the IVH patients and in seven of the remaining patients. Seven out of thirteen patients suffering from IVH exhibited more than one episode with ICP exceeding 50 mmHg, ranging from 35 up to 180 seconds. Three out of nine patients without IVH presented with such episodes, but only one of these patients presented with more than one. CONCLUSIONS: Endoscopic procedures within the cerebral ventricles are considered relatively uncomplicated procedures. However, patients undergoing treatment of IVH may suffer prolonged elevated ICP which may be critical because of their age and co-morbidity.

Safety and Accuracy of Ultrasound-guided Burr Hole Brain Abscess Aspiration.

BACKGROUND: Ultrasound-guided burr hole biopsies or catheter placements are quick and safe procedures. The use of these procedures for treatment of brain abscesses has been reported, but larger series are missing. The aim of our study was to evaluate the accuracy and safety of the methods. PATIENTS: Twenty-five brain abscess aspirations in 17 patients were analyzed. Fourteen procedures were performed to evacuate abscesses in eloquent regions; another 3 were located deeply in the cerebellar hemispheres. RESULTS: In all the procedures, a histopathologic diagnosis could be established. Only one transient deterioration of a hemiparesis occurred; other operative complications were not observed. Six patients needed more than one operation due to a relapse of the abscess. Two out of three cerebellar abscesses could be cured with one aspiration. Thirteen patients had an excellent outcome, and 2 remained severely disabled. One patient died from cerebritis and another from a neoplasm. In every procedure, a proper visualization of the abscess and monitoring of the penetration and aspiration could easily be performed. CONCLUSION: Ultrasound-guided burr hole aspiration is minimally invasive, quick, and has a very low complication rate. It offers the advantage to adapt to intraoperatively changing anatomy. The rate of recurrence is not lower than in other treatment modalities.

An ultrasound study of brain tissue biomechanics in patients following craniectomy.

So far, little attention has been paid to the biomechanical aspects of decompressive craniectomy. The brain tissue deformation occurring in these patients is difficult to quantify. Twenty-six patients suffering from a large bone defect after craniectomy were examined in supine position. The third ventricle's axial diameter was measured by transcranial ultrasound. Subsequently, the patient was brought into a sitting position. After 5 minutes, another measurement was taken. This procedure was repeated about 7 days after cranioplasty. The patients were grouped according to "early cranioplasty" (cranioplasty within 40 days after craniectomy, median 30 days) and "late cranioplasty", (cranioplasty more than 40 days, median 80 days). Data of 13 healthy volunteers were used as a reference standard. In the healthy volunteers, the third ventricle was enlarging after reaching the sitting position. The median diameter was 2.35 mm in the lying and 2.9 mm in the sitting position (p > 0.05). In the patients before early cranioplasty, a decrease of the diameter after reaching the sitting position was observed. The mean diameter was 7.0 mm in the lying and 5.9 mm in the sitting position (p > 0.01). This difference was not significant in patients before late cranioplasty (9.7 vs. 9.4 mm). After cranioplasty, the mean diameter was 6.6 and 6.2 mm in the early cranioplasty group and 9.2 mm and 9.4 mm in the late cranioplasty group (lying and sitting position, respectively). This data demonstrate for the first time that unphysiological orthostatic brain tissue deformation occurs in patients after craniectomy.

A remote control for intraoperative ultrasound--is it really necessary?

BACKGROUND: A remote control, which can be used to manipulate the scanner functions remotely from within the sterile field, is designed to save time during IOUS. This study was designed to evaluate whether the time saved by using a remote control should be a decisive factor in buying a special system. METHODS: During 50 intracranial operations, the temporary arrest of the operative procedure caused by the use of ultrasound was measured. In 25 arbitrarily chosen operations, the remote control was draped and used (group 1); in the other group (group 2), it was not used. In addition, we analyzed the use of vascular duplex sonography in 12 of the operations with remote control (group 1a) and 14 of the operations without remote control (group 2a). RESULTS: The average time spent for ultrasound use including draping was 390 seconds in group 1, compared to 388 seconds in group 2 (without remote control). During examinations including duplex sonography, the average time spent for IOUS including draping was 464 seconds for group 1a and 466 seconds for group 2a. CONCLUSION: Based on results, the neurosurgeon does not save much time by using a remote control. The time used for draping the additional remote control is equal to the length of time that is saved. However, the surgeon's frustration in attempting to instruct a layperson to operate the ultrasound keyboard and its impact on the operative procedure cannot be measured.

Polyether Ether Ketone Cranioplasties Are Permeable to Diagnostic Ultrasound.

It is a common assumption that the human skull and solid skull implants are impermeable to diagnostic ultrasound. We demonstrated in 2 patients that frontoparietal polyetheretherketone cranioplasties allowed useful imaging of intracranial parenchymal and vascular structures with higher ultrasound frequencies than the 2 MHz used for the temporal bone window. This knowledge about additional imaging properties may be helpful in emergency situations and for vascular monitoring. The decision for a polyether ether ketone cranioplasty may contribute to patient safety.

Differential somatostatin, CXCR4 chemokine and endothelin A receptor expression in WHO grade I-IV astrocytic brain tumors.

PURPOSE: Glioblastomas represent the most common primary malignant tumor of the nervous system and the most frequent type of astrocytic tumors. Despite improved therapeutic options, prognosis has remained exceptionally poor over the last two decades. Therefore, new treatment approaches are urgently needed. An overexpression of somatostatin (SST) as well as chemokine CXCR4 and endothelin A (ETA) receptors has been shown for many types of cancer. Respective expression data for astrocytic brain tumors, however, are scarce and contradictory. METHODS: SST subtype, CXCR4 and ETA expression was comparatively evaluated in a total of 57 grade I-IV astrocytic tumor samples by immunohistochemistry using well-characterized monoclonal antibodies. RESULTS: Overall, receptor expression on the tumor cells was only very low. SST5 was the most prominently expressed receptor, followed by SST3, ETA, SST2 and CXCR4. In contrast, tumor capillaries displayed strong SST2, SST3, SST5, CXCR4 and ETA expression. Presence of SST5, CXCR4 and ETA on tumor cells and of SST3, CXCR4 and ETA on microvessels gradually increased from grade II to grade IV tumors. Ki-67 values correlated significantly with CXCR4 expression on tumor cells and with vascular SST3, CXCR4 or ETA positivity. SST5 or CXCR4 positivity of tumor cells and vascular SST3 or CXCR4 expression negatively correlated with patient outcome. CONCLUSIONS: Though having some prognostic value, SST, CXCR4 or ETA expression on astrocytic tumor cells is clearly of no therapeutic relevance. Indirect targeting of these highly vascularized tumors via SST3, SST5, CXCR4 or ETA on the microvessels, in contrast, may represent a promising additional therapeutic strategy.

Lumbar subdural haematoma after temporomesial resection in epilepsy patients--report of two cases and review of the literature.

We present two cases of lumbar subdural haematoma, both occurring after an uneventful temporomesial focus resection in patients suffering from medically intractable epilepsy. Initial symptom was back pain and sciatica 4 days and 13 days postoperatively, but no neurological deficits were observed. The diagnosis was confirmed by MRI. No risk factor could be identified. The pain responded well to conservative treatment and the haematomas resolved without neurological sequelae. A review of the literature reveals that the characteristics of spinal subdural haematoma following craniotomy are very similar. Six out of 12 reported cases occurred in temporal epilepsy surgery. All had a benign course and did not require an operative procedure. Back pain after epilepsy surgery may be caused by an intraspinal haematoma and should be investigated by MRI.

The value of intraoperative ultrasonography during the resection of relapsed irradiated malignant gliomas in the brain.

PURPOSE: The aim of this study was to investigate whether intraoperative ultrasonography (IOUS) helped the surgeon navigate towards the tumor as seen in preoperative magnetic resonance imaging and whether IOUS was able to distinguish between tumor margins and the surrounding tissue. METHODS: Twenty-five patients suffering from high-grade gliomas who were previously treated by surgery and radiotherapy were included. Intraoperatively, two histopathologic samples were obtained a sample of unequivocal tumor tissue (according to anatomical landmarks and the surgeon's visual and tactile impressions) and a small tissue sample obtained using a navigated needle when the surgeon decided to stop the resection. This specimen was considered to be a boundary specimen, where no tumor tissue was apparent. The decision to take the second sample was not influenced by IOUS. The effect of IOUS was analyzed semi-quantitatively. RESULTS: All 25 samples of unequivocal tumor tissue were histopathologically classified as tumor tissue and were hyperechoic on IOUS. Of the boundary specimens, eight were hypoechoic. Only one harbored tumor tissue (P=0.150). Seventeen boundaries were moderately hyperechoic, and these samples contained all possible histological results (i.e., tumor, infiltration, or no tumor). CONCLUSION: During surgery performed on relapsed, irradiated, high-grade gliomas, IOUS provided a reliable method of navigating towards the core of the tumor. At borders, it did not reliably distinguish between remnants or tumor-free tissue, but hypoechoic areas seldom contained tumor tissue.

Epidermal growth factor receptor inhibition for the treatment of glioblastoma multiforme and other malignant brain tumours.

Gliomas are the most common primary central nervous system tumours and about 55% are glioblastoma multiforme (GBM). Between 40% and 50% of GBM have dysregulated epidermal growth factor receptor (HER1/EGFR), and almost half of these co-express the mutant receptor subtype EGFRvIII, which may contribute to the aggressive and refractory course of GBM. Limited therapeutic options exist for GBM, and recurrence is common. Standard therapy is surgical resection, where possible, and radiotherapy. Adjuvant chemotherapy provides a modest survival benefit. New therapies are essential, and HER1/EGFR-targeted agents may provide a viable strategy. The HER1/EGFR tyrosine kinase inhibitors erlotinib and gefitinib are in advanced clinical development for glioma, and a number of trials are in progress, or have recently been completed. Preliminary results with gefitinib show no objective responses, but do provide evidence of disease control. In contrast, preliminary data with erlotinib appear more encouraging. Erlotinib inhibits wild-type HER1/EGFR and EGFRvIII, which may underlie its promising clinical activity. Other HER1/EGFR-targeted agents are also being investigated for glioma, including monoclonal antibodies, radio-immuno conjugates, ligand-toxin conjugates, antisense oligonucleotides and ribozymes. Further studies will define their clinical potential and hopefully provide new, effective treatments for GBM and other malignant brain tumours.

Blood flow velocities in the basal cerebral vein after head trauma: a prospective study in 82 patients.

BACKGROUND AND PURPOSE: The authors' aim was to evaluate the time course of the basal vein's (BVR) mean flow velocity (VBVR) in patients after traumatic brain injury and its relation to intracranial pressure (ICP), cerebral perfusion pressure (CPP), and the clinical outcome. METHODS: In 82 head-injured patients (13 women and 69 men, median age = 31 years, Glasgow Coma Score = 15 to 3), daily measurement of the basal cerebral vein's and the middle cerebral artery's (MCA) flow velocities and pulsatilities was performed during each patient's entire stay in the intensive care unit. No angle correction was performed. A computerized sonography system (SD 800, Philips, Irvine, CA) with a 2.0-MHz to 2.5-MHz transducer was used for all measurements. The Glasgow Outcome Score (GOS) was evaluated after 6 months. RESULTS: During the study period, VBVR values on the side of trauma were higher in the patients with favorable outcomes (GOS = 4 and 5) compared to patients with unfavorable outcomes (GOS = 2 and 3). This was statistically significant on days 4, 6, 7, and 11 and was not observed in the mean flow velocity of the MCA (VMCA). VBVR values among the good-outcome group tended to exceed the normal mean flow velocity (9.1 cm/s), whereas the unfavorable-outcome group was below this level. A correlation between venous flow velocity or pulsatility and ICP or CPP was not observed. CONCLUSIONS: Repetitive Doppler examination of the basal cerebral veins may add new aspects to the monitoring of head-injured patients.

Trigeminal evoked potentials and sensory deficits in atypical facial pain--a comparison with results in trigeminal neuralgia.

Trigeminal evoked potentials (TEPs) and sensory deficits in eighty-three patients admitted for first surgical treatment of facial pain were retrospectively analysed. Thirty-seven patients suffered from trigeminal neuralgia (TN), 10 from symptomatic TN (sTN), and 36 from atypical facial pain (AFP). Eighteen percent of the TN patients reported sensory deficits on the pain side, but 35% had delayed ipsilateral N13 waves. Of the sTN patients, 60% had either sensory deficits or a pathological corneal reflex and 62.5% a pathological N13. Of the AFP patients, 61% complained of sensory deficits, but only 31% had a pathological N13. The percentage of pathological P19 waves was slightly lower (20%, 50%, and 11%, respectively), but showed a similar trend. Normal TEPs were found even in the presence of a sensory deficit (reported only in the AFP group). These findings may add weight to the hypothesis of underlying psychiatric disorders in AFP.

Real-time ultrasound monitoring during intracranial needle biopsies: operative results and detection of complications in 100 cases.

OBJECTIVE: Intraoperative ultrasound displays dynamic processes intraoperatively. Performing burr-hole biopsies under a real-time visual control is an interesting option for the neurosurgeon. However, the percentage of conclusive diagnoses obtained by this technique and the rate of complications must be evaluated in a larger series. METHODS: One hundred consecutive intracranial biopsies were analyzed. Through a burr hole, the lesion was localized by ultrasonography, and the planned needle trajectory was superimposed onto the image. Intracranial vessels were imaged by Doppler flow signals. Biopsies were taken in a mean depth of 41 mm (maximal 65 mm) from different parts of each tumor. RESULTS: Thirty-six lesions involved the corpus callosum, 16 lesions were located deeply within the white matter, five in the internal capsule, and one in the upper brainstem. There were three cerebellar and 17 temporal lesions. Ten tumors did not exceed a diameter of 15 mm in any plane. The mean time interval from skin incision to the end of suturing was 45 minutes, and the mean time from the surgeons entering the operating theater to leaving the theater was 63 minutes. In 95% of the lesions, a diagnosis could be established. Transient neurologic deficits occurred in five patients, which were permanent in three. In 42 patients without postoperative neurological symptoms, postoperative computed tomography scans were obtained within 24 hours; a visible hemorrhage occurred in eight (19%), six of which were seen intraoperatively. CONCLUSION: When intraoperative ultrasound-navigated biopsies were used they obtained a similar percentage of conclusive diagnoses as stereotactic biopsies. The complication rate is comparable as well. Emerging intracranial complications such as hemorrhages can be observed. However, their incidence cannot be decreased.

Successful treatment of multiple Pseudallescheria boydii brain abscesses and ventriculitis/ependymitis in a 2-year-old child after a near-drowning episode.

RATIONALE: We report on a cerebral infection by Pseudallescheria boydii in a 21-month-old boy after a near-drowning episode. MRI revealed multiple (> 60) intracerebral abscesses. METHODS: The surgical therapy included CSF drainage and microsurgical resection of one abscess for microbiological diagnosis. Antimycotic therapy included terbinafine and intraventricular caspofungin in addition to voriconazole. RESULTS: Systemic side effects of chemotherapy were not observed. After placement of a ventriculoperitoneal shunt, the boy was transferred to a rehabilitation clinic and improved neurologically. After 20 months, MRI documented a continuing remission of the disease. CONCLUSION: Our case proves that an aggressive treatment should be undertaken and can be successful in CNS pseudallescheriasis.

Malignant ectomesenchymoma of the cerebrum. Case report and discussion of therapeutic options.

UNLABELLED: Malignant ectomesenchymoma is a rare tumour that contains both ectodermal and mesenchymal elements. Only three patients with a manifestation in the cerebrum and clinicopathological data have been reported until now. We present a patient with an intracerebral ectomesenchymoma, review the literature and discuss currently available therapeutic options. In a 10-year-old girl, a left suprasellar temporo-parieto-occipitally localised tumour was diagnosed. The tumour was completely excised macroscopically in two surgical sessions. For the mesenchymal part of the tumour she subsequently underwent multidrug chemotherapy followed by radiation therapy. Considering the neuroectodermal element of the tumour, radiotherapy was applied to the craniospinal axis with a local boost. Therapy was tolerated well without any severe side effects. Six years from diagnosis, the patient is alive without a tumour relapse. CONCLUSION: Due to the sparcity of reported cases with malignant ectomesenchymoma, the role of adjuvant therapy is unclear. Multimodal therapy may be able to improve outcome.

[Trigeminal neuralgia as symptom of an infratentorial space-occupying process]. / Symptomatische Trigeminusneuralgie als Symptom einer infratentorialen Raumforderung.

UNLABELLED: Despite excellent technical means of imaging the posterior fossa by magnetic resonance imaging (MRI), some infratentorial space-occupying processes still remain undiscovered, especially if they present only slight symptoms or imitate typical different diseases. METHODS: We analysed the data of 334 patients who were admitted because of infratentorial space-occupying processes in the years 1986 to 1995. RESULTS: There were six patients with trigeminal neuralgia caused by infratentorial tumors. In only one was the tumour previously diagnosed. All suffered from tic douloureux; two had undergone operative treatment. Mean latency from first symptoms until diagnosis was 48 months. On admission all patients presented at least slight neurological deficits. Postoperatively, the patients remained pain-free. CONCLUSION: Because the prognosis of operative treatment and the occurrence of postoperative deficits depend on tumour size, we advocate MRI examination in every patient presenting tic douloureux, even without additional neurological signs.