Acute formation of lumbar discal cyst: what is the mechanism?

Lumbar discal cysts are extremely rare pathologies, with only few reports describing these lesions in the literature. Moreover, their definite pathogenesis is still unknown, with proposed theories based on radialogic and histologic findings. In this report, the authors present an acute formation of a discal cyst, which is reported for the first time. Also, we center our case on the discussion of the possible pathogenesis. Also, this is the first case of discal cyst reported in Turkey. A 67-year-old woman, whose complaints, and clinical and radiological findings demonstrated lumbar disc herniation with acute Modic 1 degererative changes of the adjacent end plates of L3-4 level. After medical and physical therapies, follow-up lumbar MRI has been taken to demonstrate a discal cyst formation on the adjacent intervertebral disc, showed cranially migrated cyst superior posterior on herniated disc, in 2 weeks period. The patient was treated by microsurgical resection of the cyst, and her complaints resolved completely.

Comparative anatomy of the porcine and human thoracic spines with reference to thoracoscopic surgical techniques.

BACKGROUND: This study compared porcine and human thoracic spine anatomies for a better understanding of how structures encountered during thoracoscopy differ between training with a porcine model and actual surgery in humans. METHODS: Parameters were measured including vertebral body height, width, and depth; disc height; rib spacing; spinal canal depth and width; and pedicle height and width. RESULTS: Although most porcine vertebral structures were smaller, porcine pedicle height was significantly greater than that of humans because the porcine pedicle houses a unique transverse foramen. The longus colli and psoas attach, respectively, to T5 and T13 in swine and to T3 and T12 in humans. In swine, the azygos vein generally was absent. The intercostal veins drained into the hemiazygos vein. CONCLUSIONS: Several thoracoscopically relevant anatomic differences between human and porcine spinal anatomies were identified. A thoracoscopic approach in a porcine model probably is best performed from the right side. The best general working area is between T6 and T10.

Capillary haemangiomas of the spinal cord: report of two cases.

The clinicopathological features of two cases of capillary haemangioma of the spinal cord are described. The presenting symptoms were similar to those of common intradural, intramedullary tumours or tumour-like mass lesions. Radiological features of these two lesions resembled other vascular lesions of the spinal cord. The patients underwent surgery, and recoveries were good. Histologically, the lesions resembled capillary haemangioma of superficial tissues that are composed of lobules of small capillaries with feeding vessels. A fibrous capsule enveloped the lesions. Capillary haemangiomas of the central nervous system are rare. Awareness of their existence may help the surgeon to avoid misdiagnosis and overtreatment of these benign tumour-like lesions.

Finite element model of the Jefferson fracture: comparison with a cadaver model.

This study tries to explain the reason why the Jefferson fracture is a burst fracture, using two different biomechanical models: a finite element model (FEM) and a cadaver model used to determine strain distribution in C1 during axial static compressive loading. For the FEM model, a three-dimensional model of C1 was obtained from a 29-year-old healthy human, using axial CT scans with intervals of 1.0 mm. The mesh model was composed of 8200 four-noded isoparametric tetrahedrons and 37,400 solid elements. The material properties of the cortical bone of the vertebra were assessed according to the previous literature and were assumed to be linear isotropic and homogeneous for all elements. Axial static compressive loads were applied at between 200 and 1200 N. The strain and stress (maximum shear and von Mises) analyses were determined on the clinically relevant fracture lines of anterior and posterior arches. The results of the FEM were compared with a cadaver model. The latter comprised the C1 bone of a cadaver placed in a methylmethacrylate foam. Axial static compressive loads between 200 and 1200 N were applied by an electrohydraulic testing machine. Strain values were measured using strain gauges, which were cemented to the bone where the clinically relevant fracture lines of the anterior and posterior arches were located. As a result, compressive strain was observed on the outer surface of the anterior arch and inferior surface of the posterior arch. In addition, there was tensile strain on the inner surface of the anterior arch and superior surface of the posterior arch. The strain values obtained from the two experimental models showed similar trends. The FEM analysis revealed that maximum strain changes occurred where the maximum shear and von Mises stresses were concentrated. The changes in the C1 strain and stress values during static axial loading biomechanically prove that the Jefferson fracture is a burst fracture.

Nitric oxide (NO) metabolism in the cerebrospinal fluid of patients with severe head injury. Inflammation as a possible cause of elevated no metabolites.

BACKGROUND: This article investigates nitric oxide (NO) metabolism following severe head injury (SHI). We wished to clarify the alterations of NO metabolism end products that is associated with SHI, and to delineate the role of inflammation in this process. METHODS: In a prospective study, we simultaneously measured the concentrations of NO metabolites and interleukin-8 (IL-8) in the ventricular cerebrospinal fluid (CSF) of 11 patients who had suffered SHI. The CSF concentrations of nitrite (NO(-)(2)) and nitrate (NO(-)(3)) combined, and of IL-8 were measured during the following four time periods post-trauma: 6 to 10, 20 to 28, 40 to 56, and 64 to 74 hours. Levels were measured using the corresponding kits. RESULTS: Compared to the ventricular CSF control values, all of our SHI patients had significantly elevated CSF levels of NO(-)(2) plus NO(-)(3) (NO(-)(2) + NO(-)(3)) and IL-8 during all periods tested. CSF NO(-)(2) + NO(-)(3) and IL-8 concentrations reached their maximums simultaneously at 20 to 28 hours following trauma (Spearman's rank correlation = 0.609, p < 0.05), and NO(-)(2) + NO(-)(3) levels were significantly higher than those measured at 6 to 10, 40 to 56, and 64 to 74 hours. [Nitrite-nitrate concentrations: 6-10 hours: 19.22 +/- 6.75, 20-28 hours: 25 +/- 6.2 micromol/l, 40-56 hours: 19.82 +/- 4.47, and 64-74 hours: 19.72 +/- 4.61 micromol/l, (p < 0.05). IL-8 concentrations: 6-10 hours: 3,232 +/- 2,976.2, 20-28 hours: 3,458.45 +/- 3,048 pg/mL, 40-56 hours: 2,616.41 +/- 2,539.21, 64-74 hours: 1,388.88 +/- 1,216.7 pg/mL, (p < 0.001).]. This simultaneous surge in NO(-)(2) + NO(-)(3) and IL-8 in the initial 24 hours post-traumatic indicated that inflammation secondary to SHI increased the rate of NO metabolism, resulting in higher levels of metabolites in the CSF. CONCLUSION: In patients with SHI, CSF concentrations of the dominant metabolites of NO are elevated in the first 3 days after trauma. A similar concurrent spike in the CSF level of IL-8, a marker of acute inflammatory response, can also be demonstrated. These data indicate that the predominant cause of the higher CSF NO(-)(2) + NO(-)(3) concentrations observed in SHI is most likely inflammation.

Posterior fossa arachnoid cysts.

Arachnoid cysts of the posterior fossa are rare lesions that are considered to be mostly congenital in origin. In this article, we retrospectively review 12 patients who underwent surgical treatment for their symptomatic posterior fossa arachnoid cysts. The most common presenting symptoms were gait disturbances and headache. The diagnosis was established on computed tomography or magnetic resonance imaging. Surgery consisted of cyst wall excision with fenestration in nine cases and shunting procedures in three cases. In all cases except one who-died, the postsurgical follow-up neuroradiological investigations showed that the cysts had decreased in size, the cerebellum had re-expanded, and if there was preoperative hydrocephalus, the ventricular size was decreased. The follow-up period ranged from 1 to 11 years. All surviving cases are free of symptoms and no arachnoid cysts recurred. The classification, pathophysiology, differential diagnosis and surgical treatment of infratentorial arachnoid cysts are discussed and the relevant literature is reviewed.

Depressed skull fracture overlying the superior sagittal sinus as a cause of benign intracranial hypertension. Case report.

The use of surgical treatment for depressed skull fractures that are located over major venous sinuses is a matter of controversy. However, if clinical and radiological findings of sinus obliteration and related intracranial hypertension are present, surgical decompression is indicated. The authors present the case of a 38-year-old man who had a depressed skull fracture overlying the posterior one-third portion of the superior sagittal sinus. The lesion was initially treated conservatively and the patient was readmitted 1 month later with signs and symptoms of intracranial hypertension. The role of radiological investigation in the detection of venous sinus flow and indications for surgical treatment are discussed. If venous sinus flow obstruction is revealed in the presence of signs and symptoms of intracranial hypertension, surgery is indicated as the first line of treatment.

Unilateral hemilaminectomy for the removal of the spinal space-occupying lesions.

In this study we have evaluated 40 patients with spinal lesions with respect to the value of unilateral hemilaminectomy. Our case study group included 29 intradural extramedullary, 6 intramedullary, and 5 extradural tumors. The thoracic spinal cord was involved in 17, the lumbar region in 13, and the cervical spinal cord in 10 cases. The mean age of the 20 males and 20 females was 35 (range 6-71). The rationale for choosing a unilateral approach is to preserve musculoligamentous attachments and bony posterior elements as much as possible. We did not observe any complication relating to unilateral hemilaminectomy. The patients were mobilized the following day after surgery or given rehabilitation therapy beginning on the second postoperative day without the use of any external support. At follow-up evaluation, a mean of 32 months postoperatively, none of the patients showed spinal deformity or spinal instability.

Bilateral traumatic abducens nerve paralysis with cervical spine flexion injury.

Bilateral traumatic abducens nerve palsy is a rare condition. We report a case associated with cervical spine flexion injury. This may be the first such case report, as no similar case was found in our review of the literature. The mechanisms of injury in this case are relevant to theories that explain hyperextension injuries.