Erkın Sonmez and Hakan Caner
Cem Yilmaz, Salih Gulsen, Erkin Sonmez, Ozkan Ozger, Muge Unlukaplan and Hakan Caner
Spinal bronchogenic cysts are rare congenital lesions. The authors describe their experience in the treatment of a 17-year-old boy who presented with back pain and paresthesia in both lower extremities. Lumbar MR imaging revealed the presence of an intramedullary cystic lesion at the conus medullaris and histopathological analysis revealed a bronchogenic cyst. To the best of the authors' knowledge, this is the first report of an intramedullary spinal bronchogenic cyst arising at the conus; all previously reported spinal bronchogenic cysts were either intradural extramedullary or not located at the conus.
Erkın Sonmez, Cem Yılmaz, Hakan Caner and Nur Altınors
✓The authors report the first description since 1957 of a lumbar disc herniation as a cause of stump pain. Most amputees frequently experience stump pain or phantom pain. The pathophysiology of phantom pain is not clearly defined; however, there are well-defined reasons for stump pain such as infection, tissue necrosis, hematoma, wound breakdown, bone spur, neuroma, and so on. During the differential diagnosis, radiculopathy due to lumbar disc herniation must also be evaluated.
Erkan Kaptanoglu, Hakan Caner, Ihsan Solaroglu and Kamer Kilinc
Object. It has been demonstrated in several experimental studies that apoptosis contributes to cellular damage after spinal cord injury (SCI). During apoptosis dying cells secrete additional mediators of apoptosis such as cytokines and free radicals which have additional toxic effects and exacerbate neuronal death. The aim of this laboratory study was to investigate the effects of mexiletine on caspase-3 activation and functional recovery and compare its post-SCI effectiveness with methylprednisolone.
Methods. The rats were divided into five groups. Animals in the trauma group underwent traumatic interventions after laminectomy. Spinal cord contusion injury was produced using the weight-drop method. Animals in treatment groups received a single dose of methylprednisolone sodium succinate (Group C), single dose of mexiletine (Group D), or vehicle solution (saline; Group E) intraperitoneally immediately after injury. Hind-limb functions were assessed using the inclined plane technique and caspase-3 activity in tissue samples was measured 24 hours after SCI. Traumatic injury was found to increase tissue caspase-3 activity. In both treatment groups the drug prevented an increase in caspase-3 activity. Mexiletine treatment improved early behavioral recovery after SCI.
Conclusions. The results obtained in this study demonstrated that mexiletine treatment inhibits caspase-3 activation and preserve/restore better neuronal function compared with methylprednisolone after experimental SCI.
Yuji Handa, Tetsuya Kubota, Akira Tsuchida, Masanori Kaneko, Hakan Caner, Hidenori Kobayashi and Toshihiko Kubota
✓ The influence of systemic hypotension on cerebral blood flow (CBF) and energy metabolism during chronic cerebral vasospasm after subarachnoid hemorrhage was studied in 15 monkeys. Changes in the phosphorus spectrum, as demonstrated by in vivo phosphorus-31 (31P) magnetic resonance (MR) spectroscopy, or in regional CBF were measured in the parietal cortex during graded hypotension. Sequential changes in the phosphorus spectrum were observed during moderate hypotension in the animals 7 days after the introduction of an autologous blood clot around the right middle cerebral artery (MCA). Angiograms revealed a reduction in vessel caliber by approximately 50% in the right MCA. The mean CBF in the spasm side decreased in parallel with a decrease in the mean arterial blood pressure (MABP) from 120 to 40 mm Hg, indicating the abolition of autoregulation. There were no significant differences in the mean percentage totals of inorganic phosphate (Pi), phosphocreatine (PCr), adenosine triphosphate (ATP), and pH between the hemispheres at baseline MABP before hypotension. The values of PCr, ATP, and pH decreased significantly (p < 0.05) and Pi increased significantly (p < 0.05) at an MABP of less than 60 mm Hg in the involved hemisphere. The ratio of PCr:Pi decreased in parallel with a decrease in MABP. The ATP showed a stepwise decrease during moderate hypotension (MABP 60 mm Hg) and was reduced significantly 20 minutes after the beginning of hypotension (p < 0.05). The results indicate that, during chronic vasospasm, changes in cerebral energy metabolism are coupled with changes in CBF in the state of impaired autoregulation. There exists a critical level for ischemia below which high-energy phosphorus metabolites become markedly depleted. It is suggested that 31P MR spectroscopy may be useful to evaluate the ischemic vulnerability of brain tissue in order to prevent delayed neurological deficit during cerebral vasospasm.