Hakan Sabuncuoglu

Intradural cement leakage: a rare complication of percutaneous vertebroplasty

SummaryPercutaneous vertebroplasty (PV) is one of the alternative treatments for vertebral fractures. Reported significant complications include pain, radiculopathy, spinal cord compression, pulmonary embolism, infection and rib fractures. In this report, we highlight intradural cement leakage which is a rare complication of the procedure.A 49 year old man with a T12 compression fracture due to multiple myeloma was referred to the neurosurgery department from the orthopaedics and traumatology clinic after developing a right lower limb weakness following percutaneous vertebroplasty with polymethylmethacrylate. An urgent thoraco-lumbar magnetic resonance imaging was performed. The T1 and T2-weighted images demonstrated intradural extramedullary and epidural cement leakages which were hypointense on both sequences. Total laminectomy was performed at T12 and L1 and two epidural cement collections were excised on the right. Then, a dural incision from T12 to the body of L1 was done and cement material seen in front of the rootlets excised without any nerve injury. The patient was discharged after a week and referred to the haematology clinic for additional therapy of multiple myeloma. Although the cement leakage was extensive, the right leg weakness improved significantly and he began to walk with assistance 3 months later.Good quality image monitoring and clear visualisation of cement are essential requirements for PV using polymethylmethacrylate to prevent this complication from the treatment.

Anatomical relationships of intracavernous internal carotid artery to intracavernous neural structures.

The objective is to correlate the intracavernous internal carotid artery (ICA) with the position of the intracavernous neural structures. The cavernous sinuses of nine injected cadaveric heads were dissected bilaterally. As measured on computed tomographic angiograms from 100 adults, anatomical relationships and measurements of intracavernous ICA and neural structures were studied and correlated to the intracavernous ICA curvature. Intracavernous ICAs were classified as normal and redundant. The meningohypophyseal trunk (MHT) of normal ICAs appeared to be closely related to the abducens nerve compared with redundant ICAs (5.5 ± 2.1 mm versus 10.0 ± 2.5 mm, respectively; p = 0.001). The position of the inferolateral trunk (ILT) varied along the horizontal segment of the intracavernous ICA. On imaging studies the ICA curvature correlated with the kyphotic degree of the skull and similarity of the ICA curvature between sides. The safety margin for preventing iatrogenic intracavernous nerve injury during surgical exploration or transarterial embolization of vascular lesions around the MHT is high with redundant ICAs. In contrast, a transvenous endovascular approach via the inferior petrosal sinus may be too distant to reach the MHT when ICAs are redundant. Approaching lesions of the inferolateral trunk may be the same regardless of ICA type.

A rare reason of foot drop caused by primary diffuse large b-cell lymphoma of the sciatic nerve: case report

IntroductionPrimary central nervous system lymphomas account for 2% of all malignant lymphomas. Although the involvement of peripheral nerves has been previously described as a dissemination of systemic lymphomas or a direct extension to the nerve trunk from contiguous lymphomas, primary involvement of the sciatic nerve is extremely rare.CaseTo the best of our knowledge, the primary localization of lymphoma within sciatic nerve has been reported only nine times. We report, a very rare example of a primary diffuse large B-cell lymphoma of the sciatic nerve.DiscussionThe patient presented with atypical sciatica. Such symptoms can be misdiagnosed as lumbar disc pathology and magnetic resonance imaging and electrophysiological studies avoid this misinterpretation.

Accessing the recesses of the fourth ventricle: comparison of tonsillar retraction and resection in the telovelar approach.

OBJECTIVE To compare the effectiveness of the telovelar approach with tonsillar manipulation for approaching the recesses of the fourth ventricle. METHODS A telovelar approach was performed in 8 injected cadaveric heads. Areas of exposure were measured for the superolateral and lateral recesses. Horizontal angles were evaluated by targeting the cerebral aqueduct and medial margin of the lateral recess. Quantitative comparisons were made between the telovelar dissections and various tonsillar manipulations. RESULTS Tonsillar retraction provided a comparable exposure of the superolateral recess with tonsillar resection (26.4 ± 17.6 vs 25.2 ± 12.5 mm2, respectively; P = .825). Tonsillar resection significantly increased exposure of the lateral recess compared with tonsillar retraction (31.1 ± 13.3 vs 20.2 ± 11.5 mm2, respectively; P = .002). Compared with tonsillar retraction, the horizontal angle to the lateral recess increased after either contralateral tonsillar retraction (22.7 ± 4.8 vs 36.7 ± 6.5 degrees) or tonsillar resection (22.7 ± 4.8 vs 31.5 ± 7.6 degrees; all adjusted P < .01). The horizontal angle to the cerebral aqueduct increased significantly with tonsillar resection compared with tonsillar retraction (17.6 ± 2.3 vs 13.2 ± 2.8 degrees; P < .001) CONCLUSION Compared with tonsillar retraction, tonsillar resection provides a wider corridor to, and a larger area of exposure of, the cerebral aqueduct and lateral recess. Contralateral tonsillar retraction improves access to the lateral recess by widening the surgical view from the contralateral side.

Total resection of inferiorly located sacral chordoma with posterior only approach: case report and review of the literature.

Chordoma is a primary sacral neoplasm of ectodermal origin and makes up %1- 4 of all primary bone tumors. It is usually present on the midline cerebrospinal axis and the most common locations are the spheno-clival region and the sacrum. The treatment of primary sacral tumors represents a challenge because of a large tumor mass at presentation and a hemorrhage risk in surgery. Sacral tumors may present a difficult problem to the surgeon who desires to obtain a clear margin of excision. Using the retrorectal fat tissue as a cleavage line in the posterior approach guides the neurosurgeon to resect the tumor totally and reduce the hemorrhage in sacral chordomas. In this case report, we tried to discuss the advantages of using of retrorectal fat tissue as a cleavage line in sacral chordomas under the literature.

Accessing the Basilar Artery Apex: Is the Temporopolar Transcavernous Route an Anatomically Advantageous Alternative?

The restricted operative field, difficulty of obtaining proximal vascular control, and close relationship to important anatomic structures limit approaches to basilar apex aneurysms. We used a cadaveric model to compare three surgical transcavernous routes to the basilar apex in the neutral configuration. Five cadaveric heads were dissected and analyzed. Working areas and length of exposure provided by the transcavernous (TC) approach via pterional, orbitozygomatic, and temporopolar (TP) routes were measured along with assessment of anatomic variation for the basilar apex region. In the pterional TC and orbitozygomatic TC approaches, the mean length of exposure of the basilar artery measured 6.9 and 7.2 mm, respectively (p = NS). The mean length of exposure in a TP TC approach increased to 9.3 mm (p < 0.05). Compared with the pterional and orbitozygomatic approaches, the TP TC approach provided a larger peribasilar area of exposure ipsilaterally and contralaterally (p < 0.05). The multiplanar working area related to the TP TC approach was 77.7 and 69.5% wider than for the pterional TC and orbitozygomatic TC, respectively. For a basilar apex in the neutral position, the TP TC approach may be advantageous, providing a wider working area for the basilar apex region, improving maneuverability for clip application, fine visualization of perforators, and better proximal control.

Severe hypertension and tachycardia during transforaminal endoscopic discectomy – Is indigocarmine to blame?

Endoscopic transforaminal discectomy is a minimally invasive technique used for the surgical treatment of herniated discs. Indigocarmine is a dye which is widely used to identify the ureteral orifice in urologic procedures. Hemodynamic effects such as hypotension and anaphylaxis in addition to hypertension, bradycardia and atrioventricular block have been reported in intravenous application of indigocarmine. The aim of this case report is to prepare anesthesiologists for such cases and make them consider invasive blood pressure monitorization. Both patients had radicular pain radiating to the leg and scheduled to undergo transforaminal endoscopic discectomy. Intraoperative vital signs were within normal limits, however severe hypertension and tachyarrhythmia developed following the injection. Hemodynamics in both patients returned to normal following lidocaine and nitroglycerine injection.

Non-invasive detection and monitoring of experimental hydrocephalus with distortion product otoacoustic emissions

OBJECTIVE We aimed to find out the effects of short term and long term hydrocephalus and intracranial ventricular volume changes on cochlear functions by using distortion product otoacoustic emission (DPOAE) in experimental hydrocephalus rat models for the first time in literature. METHODS This study was performed with 48 healthy, adult (8 weeks old), Sprague-Dawley rats which weighed between 200 and 240g. Six groups were formed in this study: short term control, short term sham, short term hydrocephalus, long term control, long term sham and long term hydrocephalus groups. Each group contained eight rats. Short term period was 4 weeks and long term period was 8 weeks after the study started. At the end of these periods, DPOAE measurements were performed and then rats were sacrificed to determine ventricular volumes. RESULTS DPOAE values at all frequencies were significantly decreased in the short term hydrocephalus group when compared to the short term control and short term sham groups. DPOAE values at all frequencies were significantly decreased in the long term hydrocephalus group when compared to the long term control and long term sham groups. Besides, long term sham group which had higher ventricular volumes than long term control group also had lower DPOAE measurements. Significant associations were present between DPOAE measurements and ventricular volumes in hydrocephalus models. CONCLUSION The functional disturbances in cochlear functions due to hydrocephalus have been demonstrated with DPOAE measurements in this study. DPOAE measurements may be thought as an easily applicable non-invasive method in detection and follow-up of patients with hydrocephalus. Our findings should be supported with clinical studies in humans.

Vagal Nerve Stimulation Effects on Generalized-Partial Seizures and Medication in Adult Drug-Resistant Epilepsy Patients

AIM The aim of this study was to find out if vagal nerve stimulation (VNS) affect the generalized-partial seizure count and medical treatment in adult drug resistant epilepsy patients. MATERIAL AND METHODS Twenty adult patients who were diagnosed with drug-resistant epilepsy were investigated retrospectively for vagal nerve stimulator implantation between 2001 and 2010 at the Neurosurgery Departments of Ufuk University and Gulhane Military Medical Academy. The effects of vagal nerve stimulation on generalized-partial seizures and medical treatment was scored and if a significant difference was found, a comparison was made by Wilcoxon Signed Ranks test and Pairwise. For all the group analyses, the statistical significant rank was accepted as a p value < 0.05. Bonferroni correction was made when it was needed during pairwise comparisons. RESULTS VNS significantly decreased the scores of generalized-partial seizures. There was no decrease in the doses of antiepileptic drugs and the medical treatment was resumed as before the implantation. The results were correlated with the relevant literature. CONCLUSION VNS is an alternative treatment option for drug resistant epilepsy for patients who are not ideal candidates for surgery or are not healed after epilepsy surgery.

Rapid, simple technique to extend depth of field in microneurosurgical images: technical note.

OBJECTIVE To increase the extent of the depth of field and focal sharpness in highly magnified image series from cadaveric microneurosurgical anatomic study or live surgery photographs obtained with the operating microscope, providing a higher quality and more satisfactory photographic and imaging experience. METHODS We used a computer workstation, CombineZM software (Alan Hadley, United Kingdom, www.hadleyweb.pwp.blueyonder.co.uk/), an injected cadaver head specimen, and an operating microscope equipped with a digital single-lens reflex camera. Fifteen images were obtained of the dissection area through an anterior petrosal approach. The focus point was fixed to different points in each image. The images were loaded into CombineZM software for processing. RESULTS The stacking process of photographs with CombineZM freeware provides significant increase in extent of depth of field and wider area of image clarity, producing a sharp, high-quality image. CONCLUSION An image processed from a stack of photographs from cadaveric microneurosurgical studies or from the operating microscope in live surgery can be rendered to show extended 3-dimensional depth of field and clarity. This method offers improvements for editing, displaying, and publishing neurosurgical anatomic images.