Mevci Ozdemir

An attempt to treat patients who have injured spinal cords with intralesional implantation of concentrated autologous bone marrow cells

BACKGROUND AIMS Spinal cord injury is common among young subjects involved in motor vehicle accidents. Mechanisms and attempts to reverse post-traumatic pathophysiologic consequences are still being investigated. Unfortunately no effective and well-established treatment modality has been developed so far. The regeneration capability of the human nervous system following an injury is highly limited. METHODS The study involved four patients (two male, two female) who had suffered spinal cord injury as a result of various types of trauma. On neurologic examination, all the patients were determined to be in American Spinal Injury Association (ASIA) grade A. All patients were treated with decompression, stabilization and fusion for vertebral trauma anteriorly, as well as intralesional implantation of cellular bone marrow concentrates using a posterior approach 1 month after the first operation. The patients were then treated and followed-up in the physical rehabilitation clinic. RESULTS At the end of the post-operative 1-year follow-up, two of the patients were classified as ASIA C while one was classified as ASIA B. One patient showed no neurologic change; none of the patients suffered from any complications or adverse effects as a result of intralesional application of bone marrow cells. CONCLUSIONS The results of this experimental study show the potential contribution of intralesional implantation of bone marrow to neuronal regeneration in the injured spinal cord, with neuronal changes. In light of the results of this experimental study, the potential for regenerative treatment in injuries of the human spinal cord is no longer a speculation but an observation.

Regenerative Treatment in Spinal Cord Injury

Spinal cord injury is a devastating, traumatic event, and experienced mainly among young people. Until the modern era, spinal cord injury was so rapidly fatal that no seriously injured persons would survive long enough for regeneration to occur. Treatment of spinal cord injury can be summarized as follows: prevent further cord injury, maintain blood flow, relieve spinal cord compression, and provide secure vertebral stabilization so as to allow mobilization and rehabilitation, none of which achieves functional recovery. Previous studies have focused on analyzing the pathogenesis of secondary injury that extends from the injury epicenter to the periphery, as well as the tissue damage and neural cell death associated with secondary injury. Now, there are hundreds of current experimental and clinical regenerative treatment studies. One of the most popular treatment method is cell transplantation in injured spinal cord. For this purpose bone marrow stromal cells, mononuclear stem cells, mesenchymal stem cells, embryonic stem cells, neural stem cells, and olfactory ensheathing cells can be used. As a result, cell transplantation has become a promising therapeutic option for spinal cord injury patients. In this paper we discuss the effectiveness of stem cell therapy in spinal cord injury.

Surgical View of the Lumbar Arteries and Their Branches: An Anatomical Study

BACKGROUND: Although injury to the lumbar arteries during anterior spinal approaches is often encountered, there are few published articles regarding the relationship between the lumbar arteries and spinal cord ischemia. OBJECTIVE: To examine the morphology of the lumbar arteries and to emphasize their clinical importance. METHODS: With the aid of a surgical microscope, 80 lumbar arteries in 10 formalin-fixed male cadavers were studied. Measurements of these structures were made and relationships observed. RESULTS: The spinal artery was usually the first branch of the lumbar artery. The greatest lumbar artery diameter was at L4 and had a mean diameter of 3.25 mm; the smallest diameter was identified at L2 and had a mean diameter of 2.05 mm. The largest spinal artery diameter was at L3 (mean, 0.56 mm) and the smallest at L1 (mean, 0.42 mm). The largest anastomotic artery diameter was at L4 (mean, 0.42 mm) and the smallest at L1 (mean, 0.32 mm). For the right and left sides, the mean greatest distance between the origin of the lumbar artery and the tendinous arch was at L4 (mean, 40.9 and 31.8 mm, respectively) and the least at L1 (mean, 31.8 and 22.5 mm, respectively). The mean of the greatest distance between the anastomotic branch and the base of the transverse process of the lumbar vertebrae was at L4 (mean, 4.41 and 4.35 mm, respectively) and the smallest at L1 (mean, 4.04 and 4.08 mm, respectively). CONCLUSION: These anatomic findings of the lumbar segmental arteries would be useful for emphasizing their surgical importance.

Arterial vascularization patterns of the splenium: An anatomical study.

The aim of this study was to provide detailed information about the arterial vascularization of the splenium of the corpus callosum (CC). The splenium is unique in that it is part of the largest commissural tract in the brain and a region in which pathologies are seen frequently. An exact description of the arterial vascularization of this part of the CC remains under debate. Thirty adult human brains (60 hemispheres) were obtained from routine autopsies. Cerebral arteries were separately cannulated and injected with colored latex. Then, the brains were fixed in formaldehyde, and dissections were performed using a surgical microscope. The diameter of the arterial branches supplying the splenium of the CC at their origin was investigated, and the vascularization patterns of these branches were observed. Vascular supply to the splenium was provided by the anterior pericallosal artery (40%) from the anterior circulation and by the posterior pericallosal artery (88%) and posterior accessory pericallosal artery (50%) from the posterior circulation. The vascularization pattern of the splenium differs in each hemisphere and is usually supplied by multiple branches. The arterial vascularization of the splenium of the CC was studied comprehensively considering the ongoing debate and the inadequacy of the studies on this issue currently available in the literature. This anatomical knowledge is essential during the treatment of pathologies in this region and especially for splenial arteriovenous malformations. Clin. Anat. 26:675–681, 2013.

Comparative Analysis of Vertebroplasty and Kyphoplasty for Osteoporotic Vertebral Compression Fractures

Study Design A retrospective study. Purpose The aim of this study is to compare the efficacy and outcome of vertebroplasty compared with unipedicular and bipedicular kyphoplasty for the treatment of osteoporotic vertebral compression fractures in terms of pain, functional capacity and height restoration rates. Overview of Literature The vertebroplasty procedure was first performed in 1984 for the treatment of a hemangioma at the C2 vertebra. Kyphoplasty was first performed in 1998 and includes vertebral height restoration in addition to using inflation balloons and high-viscosity cement. Both are efficacious, safe and long-lasting procedures. However, controversy still exists about pain relief, improvement in functional capacity, quality of life and height restoration the superiority of these procedures and assessment of appropriate and specific indications of one over the other remains undefined. Methods Between 2004 and 2011, 296 patients suffering from osteoporotic vertebral compression fracture underwent 433 vertebroplasty and kyphoplasty procedures. Visual analogue scale (VAS), the Oswestry Disability Index (ODI) and height restoration rates were used to evaluate the results. Results Mean height restoration rate was 24.16%±1.27% in the vertebroplasty group, 24.25%±1.28% in the unipedicular kyphoplasty group and 37.05%±1.21% in the bipedicular kyphoplasty group. VAS and ODI scores improved all of the groups. Conclusions Vertebroplasty and kyphoplasty are both effective in providing pain relief and improvement in functional capacity and quality of life after the procedure, but the bipedicular kyphoplasty procedure has a further advantage in terms of height restoration when compared to unipedicular kyphoplasty and vertebroplasty procedures.

Neurovascular structures adjacent to the lumbar intervertebral discs: an anatomical study of their morphometry and relationships

OBJECT Although infrequent, injury to adjacent neurovascular structures during posterior approaches to lumbar intervertebral discs can occur. A detailed anatomical knowledge of relationships may decrease surgical complications. METHODS Ten formalin-fixed male cadavers were used for this study. Posterior exposure of the lumbar thecal sac, nerve roots, pedicles, and intervertebral discs was performed. To identify retroperitoneal structures at risk during posterior lumbar discectomy, a transabdominal retroperitoneal approach was performed, and observations were made. The distances between the posterior and anterior edges of the lumbar intervertebral discs were measured, and the relationships between the disc space, pedicle, and nerve root were evaluated. RESULTS For right and left sides, the mean distance from the inferior pedicle to the disc gradually increased from L1-2 to L4-5 (range 2.7-3.8 mm and 2.9-4.5 mm for right and left side, respectively) and slightly decreased at L5-S1. For right and left sides, the mean distance from the superior pedicle to the disc was more or less the same for all disc spaces (range 9.3-11.6 mm and 8.2-10.5 mm for right and left, respectively). The right and left mean disc-to-root distance for the L3-4 to L5-S1 levels ranged from 8.3 to 22.1 mm and 7.2 to 20.6 mm, respectively. The root origin gradually increased from L-1 to L-5. The right and left nerve root-to-disc angle gradually decreased from L-3 to S-1 (range 105°-110.6° and 99°-108°). Disc heights gradually increased from L1-2 to L5-S1 (range 11.3-17.4 mm). The mean distance between the anterior and posterior borders of the intervertebral discs ranged from 39 to 46 mm for all levels. CONCLUSIONS To avoid neighboring neurovascular structures, instrumentation should not be inserted into the lumbar disc spaces more than 3 cm from their posterior edge. Accurate anatomical knowledge of the relationships of intervertebral discs to nerve roots is needed for spine surgeons.

Window anatomy for neurosurgical approaches. Laboratory investigation.

OBJECT Knowledge of the cranium projections of the gyral structures is essential to reduce the surgical complications and to perform minimally invasive interventions in daily neurosurgical practice. Thus, in this study the authors aimed to provide detailed information on cranial projections of the eloquent cortical areas. METHODS Ten formalin-fixed adult human skulls were obtained. Using sutures and craniometrical points, the crania were divided into 8 windows: superior frontal, inferior frontal, superior parietal, inferior parietal, sphenoidal, temporal, superior occipital, and inferior occipital. The projections of the precentral gyrus, postcentral gyrus, inferior frontal gyrus, superior temporal gyrus, transverse temporal gyri, Heschl gyrus, genu and splenium of the corpus callosum, supramarginal gyrus, angular gyrus, calcarine sulcus, and sylvian fissure to cranial vault were evaluated. RESULTS Three-fourths of the precentral gyrus and postcentral gyrus were in the superior parietal window. The inferior frontal gyrus extended to the inferior parietal window in 80%. The 3 important parts of this gyrus were located below the superior temporal line in all hemispheres. The orbital and triangular parts were in the inferior frontal window, and the opercular part was in the inferior parietal window. The superior temporal gyrus was usually located in the inferior parietal and temporal windows, whereas the supramarginal gyrus and angular gyrus were usually located in the superior and inferior parietal windows. The farthest anterior point of the Heschl gyrus was usually located in the inferior parietal window. The mean positions of arachnoid granulations were measured as 3.9 +/- 0.39 cm anterior and 7.3 +/- 0.51 cm posterior to the bregma. CONCLUSIONS Given that recognition of the gyral patterns underlying the craniotomies is not always easy, awareness of the coordinates and projections of certain gyri according to the craniometric points may considerably contribute to surgical interventions.

Effect of Subthalamic Nucleus Stimulation on Pedunculopontine Nucleus Neural Activity

Background: The pedunculopontine nucleus has recently been proposed as an alternative target for deep brain stimulation for the treatment of medically intractable Parkinsons disease. The suggested indication for pedunculopontine nucleus deep brain stimulation is severe and medically intractable axial symptoms such as gait and postural impairment. Objective: Our goal in this study was to describe the effects of subthalamic nucleus stimulation on pedunculopontine nucleus electrophysiological activity. Methods: Fourteen male Wistar rats were divided into a sham stimulation group and an experimental group. In both groups, electrodes were implanted bilaterally into the subthalamic nucleus and into the right pedunculopontine nucleus. Microelectrode recordings were carried out in both groups prior to and during subthalamic nucleus stimulation. Results: Subthalamic nucleus stimulation produced no clear inhibition of neuronal firing in the pedunculopontine nucleus. However, we found that stimulation of the subthalamic nucleus at 60 Hz produces some entrainment of pedunculopontine nucleus neuronal firing and a shift of subthalamic nucleus firing patterns to more tonic and random patterns. These results are consistent with the effects of deep brain stimulation on neuronal activity in the subthalamic nucleus and globus pallidus internus. Conclusion: The result of this study provides additional evidence to improve our understanding of the mechanism of subthalamic nucleus-deep brain stimulation, and its physiological consequences.

CT-guided percutaneous cordotomy for intractable pain in what is more than a disease: lung malignancies.

AIM Lung cancer is the leading cause of cancer-related mortality worldwide. Pain is a common problem in these patients, yet inadequate or dissatisfactory management is prevalent. MATERIAL AND METHODS Between 1987 and 2012, 224 patients with intractable pain were treated with computerized tomography (CT)- guided cordotomy. Among them, 210 had intractable pain due to malignancies. The majority of the cases were diagnosed as pulmonary malignancies (108 patients). Sixty-seven were pulmonary carcinoma, 26 mesothelioma and 15 Pancoast tumors. RESULTS After cordotomy, 98.13% of cancer patients reported initial pain relief. Minimum and maximum preoperative scores of the Karnofsky Performance Scale were 20 and 70, versus postoperative scores of 40 and 90 (p < 0.001). The median preoperative VAS score was 8 (6-9). On the first postoperative day, the score dropped sharply to 0 (0-8) (p < 0.001). In this selected series of 108 percutaneous cordotomy procedures, as well as in the total series of 224 patients, there was no mortality or major morbidity. CONCLUSION CT-guided percutaneous cordotomy is an effective procedure that should be used in the treatment of cancer-related pain problems. We suggest that cordotomy should be preferred as soon as possible in patients who fail to respond to the classic analgesic therapy.

New practical landmarks to determine sigmoid sinus free zones for suboccipital approaches: an anatomical study.

Abstract Literature defines the landmarks to identify the courses and locations of the transverse and sigmoid sinuses on the outer surface of the skull and inner surface of the scalp. These natural landmarks may only be helpful after skin incision and are inadequate to determine the length and size of the skin incision. Still, there is a need to identify palpable landmarks easily to determine the ideal location to open the initial burr hole before an operation. Twenty-eight dried adult human skulls and 2 cadavers were evaluated. The zygomatic root, the inion, and the mastoid process were identified on the external, and the grooves for sigmoid and transverse sinuses, on the internal surfaces. The distances between the 3 landmarks and the midpoints, and the shortest distances of the midpoints to the border of the groove for sigmoid sinus and groove for transverse sinus were measured. Statistically significant differences were evaluated for both sides. Based on the measurements, the defined “artificial landmarks” can be considered safe points that involve no vascular structures and may be used to perform the initial burr hole during posterolateral approaches. Identification of the midpoints and palpation of the defined landmarks easily before the operation render the study feasible and practical unlike with natural landmarks. To avoid venous injury, the midpoints of mastoid-inion line and zygomatic root-inion line can be used safely in skin incision during posterior fossa approaches and craniotomy.