Prognostic significance of preoperative electrophysiologic investigation for facial nerve outcome in acoustic neuroma surgery

The prognostic significance of transcranial magnetic stimulation and nasal muscle F-wave recording to predict postoperative facial nerve function was assessed in 24 patients with unilateral acoustic neuromas (mean diameter, 31 mm) and clinically intact facial nerve function. Latency of F waves and response to cortical magnetic stimulation, as well as F ratios, central motor conduction time, and the ratio of response latency to cortical and cisternal magnetic stimulation were significantly increased. Outcome analysis revealed no significant correlation between preoperative electrophysiologic changes and postoperative facial nerve function. However, a significant correlation with tumor diameter was detected. Thus, acoustic neuroma size seems to be the best predictor of facial nerve function after surgery.     

Variability in infectivity of primary cell cultures of human brain tumors with HSV-1 amplicon vectors

We investigated the variability in infectivity of cells in primary brain tumor samples from different patients using an HSV-1 amplicon vector. We studied the infectivity of HSV-1 amplicon vectors in tumor samples derived from neurosurgical resections of 20 patients. Cells were infected with a definite amount of HSV-1 amplicon vector HSV-GFP. Transduction efficiency in primary tumor cell cultures was compared to an established human glioma line. Moreover, duration of transgene expression was monitored in different tumor cell types. All primary cell cultures were infectable with HSV-GFP with variable transduction efficiencies ranging between 3.0 and 42.4% from reference human Gli36 Delta EGFR glioma cells. Transduction efficiency was significantly greater in anaplastic gliomas and meningiomas (26.7+/-17.4%) compared to more malignant tumor types (glioblastomas, metastases; 11.2+/-8.5%; P=0.05). To further investigate the possible underlying mechanism of this variability, nectin-1/HevC expression was analyzed and was found to contribute, at least in part, to this variability in infectability. The tumor cells expressed the exogenous gene for 7 to 61 days with significant shorter expression in glioblastomas (18+/-13 d) compared to anaplastic gliomas (42+/-24 d; P<0.05). Interindividual variability of infectivity by HSV-1 virions might explain, at least in part, why some patients enrolled in gene therapy for glioblastoma in the past exhibited a sustained response to HSV-1-based gene- and virus therapy. Infectivity of primary tumor samples from respective patients should be tested to enable the development of efficient and safe herpes vector-based gene and virus therapy for clinical application.     

Hypertrophy of the lumbar ligamentum flavum is associated with inflammation-related TGF-β expression

Background  

Despite the significance of hypertrophy of the ligamentum flavum (HLF) in the disease progress of neurogenic claudication, the cellular mechanisms underlying the gradual fibrotic thickening of the ligamentum flavum remain poorly understood. The aim of our study was to get insight into the contribution of inflammatory mechanisms to the development of hypertrophy.     

Invasive pulmonale Aspergillose

Invasive pulmonary aspergillosis (IPA) is a life-threatening infection predominantly affecting immunocompromised patients, e.g. with acute leukemia. This case report demonstrates that IPA can also occur in non-neutropenic critically ill surgical patients. The case of a 63-year-old woman is reported, who developed IPA of the respiratory tract in the course of diffuse purulent peritonitis. First-line therapy with voriconazol failed to be effective. However, application of caspofungin, intensive kinetic therapy (including prone position) and airway management by interventional bronchoscopy enabled successful treatment of this severe complication.     

Three-dimensional analysis of positional plagiocephaly before and after molding helmet therapy in comparison to normal head growth

Objective

Stereophotogrammetry enables a simple and radiation free longitudinal analysis of skull asymmetries: in a three-dimensional coordinate system various distances (length, breadth, cephalic index, oblique diameters, ear shift, head circumference) can be analyzed. We also defined separate volume sections in order to further quantify the degree of asymmetry in the posterior and anterior components of both sides of the head.

Patients and methods

In 51 infants (mean age, 6 months; SD 0.97) with positional plagiocephaly, we determined these parameters at the beginning as well as at the end of molding helmet therapy (mean therapy time 4.9 months). Thirty-seven infants without positional deformity (mean age, 6.4 months; SD 0.3) served as control group and provided data about what appears to be normal and how these parameters change during growth over a comparable period of time.

Results

Compared with the control group, the plagiocephalic heads were more brachycephalic, but closely approximated the normal shape under molding therapy. The striking volume difference between the left and right posterior sections in the plagiocephalic children (the mean volume of the flattened side being 21 % smaller than the one on the contralateral side) improved as well (to a residual difference of mean 8 %) and ended up with a value close to the control group (mean 6 %).

Conclusion

There is a broad clinical application area for stereophotogrammetry analyzing skull morphology: In plagiocephalic infants we demonstrate impressive changes of head shape under molding therapy; in normal-looking infants we describe the extent of unperceived asymmetry.     

Lesions of the corpus callosum in hydrocephalic patients with ventricular drainage — a CT-study

Summary Patients with ventricular drainage may develop lesions of the corpus callosum. In order to study frequency, pathogenesis and clinical relevance of callosal lesions, 301 routine CT investigations of 79 patients with ventricular drainage were reviewed. Hypodense lesions in the anterior part of the corpus callosum were observed in 7 patients with longstanding hydrocephalus of variable origin, in 2 cases the corpus callosum was slightly swollen. All 7 patients showed signs of forced ventricular drainage. The callosal alterations were clinically inapparent and potentially reversible. Knowledge of these lesions is important to avoid misinterpretation.     

Relevance of magnetic resonance imaging for ventricular endoscopy.

OBJECTIVE: Endoscopic procedures may represent an alternative to microsurgery or shunt operations in intra- or paraventricular pathologies. However, the operative results mainly depend on the selection of suitable patients. In the present study of 30 patients with occlusive hydrocephalus, the relevance of differentiated magnetic resonance (MR) imaging for evaluation of the pathophysiological and anatomic prerequisites was investigated. PATIENTS AND METHODS: Apart from conventional axial T(2) -weighted turbo spin echo (TSE) sequences (TR/TE 2126/100 ms) and T(1) -weighted spin echo (SE) sequences (TR/TE 450/15 ms) with and without the administration of Gd-DTPA, the MR protocol included sagittal and coronal thin-sliced T(2) -weighted TSE sequences, cardiac-triggered (TR/TE > 2700/120 ms, slice thickness 3.0 mm) or in volume technique (TR/TE 4000/180 ms, slice thickness 1.4 mm). For the visualization of CSF flow, a sagittal and axial phase-contrast-multi-heart-phase (PCMHP) measurement with 16 phases per cardiac cycle and flow sensitivity in the cranio-caudal direction (TR/TE 18/9.5 ms and 14/9.5 ms) was performed. RESULTS: The combination of imaging and flow sequences provided most information about the extent and the etiology of hydrocephalus. An obstruction of CSF pathways could be detected by the absence of flow voids in T(2) -weighted TSE sequences or of flow signals in PCMHP sequences. The size of the foramen of Monro and of the third ventricle could be evaluated in thin-sliced T(2) -weighted TSE sequences, for the foramen of Monro in coronal and sagittal and for the third ventricle in coronal and axial slice direction, respectively. The basal structures of the third ventricle, including its floor, the infundibular recess, the mamillary bodies, and the basilar artery, could be best identified in sagittal thin-sliced T(2) -weighted TSE scans, cardiac-triggered or in volume technique. CONCLUSION: In occlusive hydrocephalus, a differentiated MR protocol with thin-sliced T(2) -weighted TSE sequences and phase-contrast sequences allows a very precise estimation of the pathophysiological and the anatomic prerequisites for endoscopic procedures. Furthermore, MR imaging can be used for the follow-up documentation of ventriculo-cisternostomies, -cytostomies, or openings of other membranes.     

Controlled Hypercapnia Enhances Cerebral Blood Flow and Brain Tissue Oxygenation After Aneurysmal Subarachnoid Hemorrhage: Results of a Phase 1 Study

Background

This study investigated if cerebral blood flow (CBF) regulation by changes of the arterial partial pressure of carbon dioxide (PaCO₂) can be used therapeutically to increase CBF and improve neurological outcome after subarachnoid hemorrhage (SAH).

Methods

In 12 mechanically ventilated poor-grade SAH-patients, a daily trial intervention was performed between day 4 and 14. During this intervention, PaCO₂ was decreased to 30 mmHg and then gradually increased to 40, 50, and 60 mmHg in 15-min intervals by modifications of the respiratory minute volume. CBF and brain tissue oxygen saturation (StiO₂) were the primary and secondary endpoints. Intracranial pressure was controlled by an external ventricular drainage.

Results

CBF reproducibly decreased during hyperventilation and increased to a maximum of 141 ± 53 % of baseline during hypercapnia (PaCO₂ 60 mmHg) on all days between day 4 and 14 after SAH. Similarly, StiO₂ increased during hypercapnia. CBF remained elevated within the first hour after resetting ventilation to baseline parameters and no rebound effect was observed within this time-span. PaCO₂-reactivities of CBF and StiO₂ were highest between 30 and 50 mmHg and slightly decreased at higher levels.

Conclusion

CBF and StiO₂ reproducibly increased by controlled hypercapnia of up to 60 mmHg even during the period of the maximum expected vasospasm. The absence of a rebound effect within the first hour after hypercapnia indicates that an improvement of the protocol is possible. The intervention may yield a therapeutic potential to prevent ischemic deficits after aneurysmal SAH.