Andreas Jödicke

Boswellic acids inhibit glioma growth : a new treatment option?

Conventional malignant glioma therapy (surgery, radiation therapy and chemotherapy) does not yield satisfying results. The prognosis of the glioma patient depends more on the histological grading of the tumor and patients age than on the therapy. Especially the adjuvant chemotherapy failed to date to influence survival time in glioma patients significantly. To improve results in malignant glioma therapy additional therapeutic regimes are necessary.In an earlier study we were able to show a significant reduction on perifocal edema by an extract from gum resin (EGR) accompanied with a clinical improvement in patients with malignant glioma. Also a decrease of urinary LTE4-excretion as a metabolite of leukotriene synthesis in brain tumors was observed. Furthermore we had found a proliferation inhibiting activity of the extract form EGR, the boswellic acids in cell cultures.The purpose of this experimental study was to elucidate the effects of the boswellic acids, which are constituents of an extract from gum resin on tumor growth in vivo. Female wistar rats weighing 200–250 g were treated with the drug 14 days after inoculation of C6 tumor cells into their right caudate nucleus and randomization into 4 groups. The treatment groups received different dosages and were compared to a control group without any additional treatment. Survival time of the rats in the highest dosage group (3 × 240 mg/kg body weight) was more than twice as long as in the control group (P < 0.05).In a second experiment the inhibition of tumor cell proliferation was examined. The C6 tumor cells were implanted into the caudate nucleus. Drug treatment was started immediately after implantation and stopped after 14 days. The animals were sacrificed and the brains were examined microscopically. Comparing low and high dosage of EGR treatment a significant difference in tumor volume was detected (P < 0.05). The proportion of apoptotic tumor cells in animals with high dose treatment was significantly larger than in the low dose (treatment) group (P < 0.05).These data demonstrate an influence of EGR in rat glioma growth and might represent a new therapeutic option on glioma treatment in man in future. Further experimental work on human gliomas is needed to definitively answer this question.

Risk factors for outcome and complications of dorsal foraminotomy in cervical disc herniation.

BACKGROUND Dorsal foraminotomy is a standard operative procedure for lateral cervical disc herniation. Factors associated with surgical complications and clinical outcome in dorsal foraminotomy of cervical disc herniation were evaluated in a retrospective cohort study. METHOD Thirty-nine patients were operated upon for unilateral, monosegmental, mediolateral cervical disc herniation (+/- associated spondylosis) from 1997 to 1999. Preoperative radiologic imaging and surgical reports were analyzed. Motor disfunction, neck irritation, and radicular pain were evaluated. Outcome was ranked according to modified Odoms criteria at 6 weeks and 1 year postoperatively. RESULTS Six weeks after injury 7 of 39 patients (18%) showed neck irritation. No new neurologic deficit was seen. All patients with preoperative paresis improved; two had early relapses of a medial soft disc prolapse (2/39). Residual radicular pain was seen in 3 of 39 patients (8%) within 30 days postoperatively, necessitating surgical revision. Factors of surgical failure were associated spondylosis (2/3) and residual mediolateral disc protrusion (1/3). In one patient with associated spondylosis, local pain due to a symptomatic fracture of the lateral process of D1 resolved after revision. Duration of preoperative radicular pain was identified as a risk factor for unfavorable outcome. CONCLUSION In lateral cervical disc herniation, associated spondylosis or medial disc protrusion poses a significant risk of surgical failure and complications of dorsal foraminotomy. Reducing the radicular failure rate by enlarging the bony decompression may lead to local failure. In well-selected patients with a lateral cervical free disc fragment, dorsolateral foraminotomy is successful and safe.

Somatosensory Evoked Potential Monitoring during Positioning of the Patient for Posterior Fossa Surgery in the Semisitting Position

OBJECTIVE Midcervical flexion myelopathy is a rare but well-known complication of posterior fossa surgery. To reduce the risk, we routinely used somatosensory evoked potential (SSEP) monitoring during positioning of the patient. METHODS Fifty-five consecutive patients were operated on for posterior fossa lesions in the semisitting position via a median (5 patients) or a lateral (50 patients) suboccipital approach. During positioning, monitoring of SSEPs by stimulation of the tibial nerve (T-SSEP) as well as by stimulation of the median nerve (M-SSEP) was established. In the case of pronounced SSEP changes, the head was repositioned. Surgery was started after SSEP recordings were unchanged as compared to the baseline investigation. RESULTS Effective monitoring was possible in all cases. Whereas M-SSEP recordings showed no changes while placing patients in the sitting position, T-SSEP recordings were altered in 14 cases (25%). In cases using the midline approach, SSEP changes were never so pronounced to require repositioning of the head. Head flexion and rotation resulted in significant changes of T-SSEP recordings in eight patients (14.5%), requiring repositioning. In two cases, an amplitude loss was noted. In only two of these eight patients were M-SSEP recordings markedly changed. SSEP recordings after repositioning disclosed recovery of spinal cord function. In no patient were clinical signs of myelopathy observed postoperatively. CONCLUSION We observed a high incidence of pronounced changes of T-SSEP recordings when the patients head was flexed and rotated for lateral suboccipital craniotomy in the semisitting position. Despite the low specificity monitoring of T-SSEPs during positioning of the patient for posterior fossa surgery, the semisitting position is strongly recommended.

Endoscopic surgical anatomy of the paediatric third ventricle studied using virtual neuroendoscopy based on 3-D ultrasonography

IntroductionEndoscopic treatment for occlusive hydrocephalus requires knowledge of individual ventricular and vascular anatomies of the ventricular system.MethodsWe studied the feasibility of virtual neuroendoscopy (VNE) based on 3-D ultrasonography (3-D US) for the identification of parenchymal and vascular anatomical landmarks of the third ventricle and its impact on the surgical planning of endoscopic third ventriculostomy (ETV) in paediatric patients. 3-D US was performed through the anterior fontanel in four infants with hydrocephalus.ResultsVirtual neuroendoscopy revealed the size of the foramen of Monro, anatomical landmarks of the floor of the third ventricle crucial for correct fenestration during ETV, but not the premesencephalic cistern. The basilar bifurcation was identified in relation to the floor of the third ventricle by VNE (power-Doppler ultrasonography) and confirmed intraoperatively after ETV.Conclusion3-D US-based VNE reveals detailed anatomical information on the ventricular system including the foramen of Monro and the floor of the third ventricle. Within the premesencephalic cistern vascular anatomy can be visualized, but not non-vascular structures.

Optimized Screw Trajectory for Lumbar Cortical Bone Trajectory Pedicle Screws Based on Clinical Outcome: Evidence Favoring the Buttress Effect Theory

Background Cortical bone trajectory (CBT) is a relatively new technique for pedicle screw insertion in the field of spine surgery. Previous studies have demonstrated the significantly better pullout and toggle characteristics the new method offers, and it appears to have certain advantages over the widely used traditional trajectory. The mechanism of the pullout and toggle characteristics still remains unknown. Purpose To report the medium‐ to long‐term follow‐up findings of patients who underwent posterior lumbar interbody fusion or posterior lumbar fusion (PLIF/PLF) at our institution and to discuss the ideal screw trajectory when using this technique. Study Design Retrospective radiologic study. Methods Fifty‐five patients who underwent PLIF/PLF for lumbar spondylosis using the new technique between January 2011 and January 2016 were included. Clinical outcome was assessed using the Japanese Orthopaedic Association scores for low back pain and visual analog scale scores. Screw loosening was evaluated via the presence of a translucent zone surrounding the pedicle screw using plain X‐radiography (Xp). The screw trajectory was evaluated by measuring the rostral range (RR) and the lateral range score (LRS). The RR is the angle between the line drawn along the distal end plate of the vertebra and the line drawn along the screw on the lateral view. The LRS is the score given depending on the position of the tip of the screw seen on the Xp taken in the anteroposterior (AP) view. The pedicle ring is equally divided into the medial third (zone A), central third (zone B), and the lateral third (zone C) by four vertical lines. A score of 0 to 3 points is given depending on the position of the tip of the screw: 0, outside the pedicle ring; 1, zone A; 2, zone B; and 3, zone C. Results Bone fusion was recorded in 49 patients (49/55 patients). The total number of screws with a visible translucent zone on Xp was 26 (26/242 screws). When the screws are inserted at a more acute angle in the lateral view (low RR) or when the screws are directed more medially (low LRS), the risk of developing a translucent zone around the pedicle screw increased. Conclusion With CBT, the pedicle screws are inserted from the pars interarticularis that is rich in cortical bone, strong enough to withstand the substantial forces usually encountered in the region. Our clinical data suggest that the optimal screw trajectory is one where the screw is inserted at an angle > 22.55 degrees (high RR) on the lateral view Xp and where the tip of the screw is directed toward the lateral third of the pedicle on the AP Xp. We believe the naturally occurring buttress effect that exists in the vertebra may give CBT a mechanical and anatomical advantage over the traditional screw trajectory.

Rehabilitation after Clipping of Cerebral Aneurysms without Acute Subarachnoid Hemorrhage: Outcome Analysis of 100 Consecutive Cases

Abstract Background Discharge to rehabilitation is reported in large studies as one important outcome parameter based on hospital codes. Because neurologic outcome scores (e.g., the modified Rankin Scale [mRS]) are missing in International Classification of Diseases (ICD) databases, rehabilitation indirectly serves as a kind of surrogate parameter for overall outcome. Reported fractions of patients with rehabilitation, however, largely differ between studies and seem high for patients with aneurysm clipping. Variances in rehabilitation fractions seem to largely differ between treatments (clipping versus coiling) for unruptured intracranial aneurysms, so we analyzed our patients for percentage of and potential factors predicting rehabilitation. Patients From July 2007 to September 2013, 100 consecutive patients with at least one cerebral aneurysm underwent aneurysm clipping. Aneurysms were classified as incidental, associated, pretreated (coil compaction after subarachnoid hemorrhage), and symptomatic (oculomotor nerve compression, microemboli), and they were assigned to their anatomical location. Complications (infection, hemorrhage, cerebrospinal fluid fistula, transient and permanent neurologic deficit, reoperation) and outcome (mRS at 6 months; clip occlusion rate by postoperative digital subtraction angiography) as well as frequency and type of rehabilitation were analyzed and correlated retrospectively. Multiple aneurysms clipped in one procedure were not counted separately regarding complications or outcome (i.e., one patient, one outcome). Results The overall complication rate was 17% including 10% early and 3% permanent neurologic deficits and 7% reoperations. There were no deaths. Overall, 98% of patients had a good outcome (mRS 0‐2). Clip occlusion rate was 97.9%. Multivariate logistic regression analysis identified aneurysm location as the only significant independent factor for risk of complication (p < 0.001) and complication as the only significant independent risk factor for rehabilitation (p = 0.003). Rehabilitation was indicated or requested by the patient as early neurologic rehabilitation (5%), inpatient follow‐up (15%), and outpatient follow‐up (15%). The long‐term care rate was 2%. Conclusion Microsurgery of unruptured and not acutely ruptured aneurysms (including post‐coil and associated aneurysms) has a low rate of rehabilitation with a low risk of a permanent neurologic deficit, long‐term care, or early neurologic rehabilitation. The rate of rehabilitation is well below reported risks from studies based on ICD‐based health care analysis. Rehabilitation per se is not a good indicator for outcome.