Seref Dogan

MR imaging in the detection of diffuse axonal injury with mild traumatic brain injury

Abstract Purpose: To evaluate the occurrence and distribution of mild traumatic brain injury (MTBI) caused by diffuse axonal injury (DAI) using magnetic resonance (MR) imaging and to attempt to correlate MR findings with post-concussion symptoms (PCS). Patients and methods: Forty MTBI patients (mean age: 32.5 years) with normal cranial computed tomography (CT) findings were examined with standard MR protocol including T1-weighted, T2-weighted, fluid attenuated inversion recovery (FLAIR), gradient echo (GRE) and diffusion-weighted (DW) sequences. MR imaging was performed within 24 hours of injury. The lesions were classified as DAI based on their location and morphologic appearance. Results: In MR imaging of five (12.5%) of the patients, the lesions compatible with DAI were observed. Four patients (10%) had the foci of low signal intensity compatible with hemorrhagic shear injury on the GRE sequence, and five (12.5%) patients had high signal intensity on FLAIR and DW sequence. Conclusion: MR imaging can be helpful in revealing DAI lesions in patients with normal CT scan findings after MTBI. FLAIR, GRE and DW sequences are superior to conventional spin-echo images in detecting DAI lesions.

Tau protein as a serum marker of brain damage in mild traumatic brain injury: Preliminary results

The objective of this study was to investigate the diagnostic value of serum tau protein in determining the severity of traumatic brain injury in patients with mild traumatic brain injury (mTBI) and high-risk patients. Adult patients who presented to our emergency department (ED) with mTBI over 1 year were prospectively enrolled. Patients underwent cranial computed tomography (CT) and were subdivided into high and low-risk groups, according to the probability of resultant intracranial injury. Serum tau levels of 60 patients and 20 healthy volunteers, who served as a control group, were measured. The mean age of the 60 patients (45 males, 15 females) was 32.5 years (range, 15–66 y). Mean Glasgow Coma Scale (GCS) score was 14±0.6. CT scans demonstrated intracranial injury in 11 patients (18.3%) and depressed fracture in 4 patients (6.7%). Serum tau levels of patients (188±210 pg/mL), compared with those of controls (86±48 pg/mL), were relatively higher; however, differences were not statistically significant (P=.445). Also, serum tau levels of high-risk patients (307±246 pg/mL) were significantly higher than those of low-risk patients (77±61 pg/mL) (P=.001). A total of 48 patients (80%) were accessible for follow-up after 6 months. Postconcussive syndrome was observed in 8 patients, 5 of whom had serum tau protein levels that were higher than those of the other 3 patients. However, no statistically significant difference was observed (P > .05). Investigators of the present study noted that serum tau levels in patients with mTBI were increased. Therefore, it is believed that this biomarker may prove helpful in identifying high-risk patients with mTBI. However, additional studies are needed to establish the diagnostic value of serum tau in detecting traumatic brain injury in patients with mTBI.

Traumatic epidural haematomas of nonarterial origin: analysis of 30 consecutive cases

SummaryBackground. The purpose was to analyse the clinical and radiological findings, and management approaches used in 30 consecutive cases of traumatic epidural haematoma of nonarterial origin treated at one centre.Method. Medical records for 30 patients surgically treated for epidural haematoma of nonarterial origin between 1997 and 2003 were reviewed. Epidural haematoma of nonarterial origin was diagnosed based on computed tomography (CT) and the bleeding source was confirmed intra-operatively. Admission status, outcome, fracture location, haematoma location/size/volume, and additional intracranial pathology were among the data noted. Two groups were formed for analysis: venous sinus bleeding (group 1) and other venous sources (group 2).Findings. The 30 cases accounted for 25% of the total number of traumatic epidural haematomas (n = 120) treated during the same period. The epidural haematomas of nonarterial origin locations were transverse sigmoid sinus (n = 11; 36.7%), superior sagittal sinus (n = 6; 20%), venous lakes (n = 5; 16.6%), diploë (n = 5; 0.16%), arachnoid granulations (n = 2; 6.7%), petrosal sinus (n = 1; 3.3%). There were 12 postoperative complications in 9 patients: recurrence (n = 4; 13.3% of the 30 total), pneumonia (n = 4; 13.3%), meningitis (n = 2; 6.7%), hydrocephalus (n = 1; 3.3%) and subdural effusion (n = 1; 3.3%). All recurrence cases were re-explored. Six (20%) patients died. Glasgow Outcome Scale (GOS) scores (mean follow-up 13.3 ± 7.8 months) revealed 22 (73.3%) patients with favourable results (GOS 4–5) and 8 (26.7%) had poor results (GOS 1–3).Conclusions. Cases of epidural haematoma of nonarterial origin differ from the more common arterial-origin epidural haematomas with respect to lesion location, surgical planning, postoperative complications, and outcome. Epidural haematoma of nonarterial origin should be suspected if preoperative CT shows a haematoma overlying a dural venous sinus or in the posterior fossa and convexity. The sinus-origin group had a high frequency of fractures which crossed the sinuses, and this might be diagnostically and surgically useful in such cases.

Pituitary apoplexy as a cause of internal carotid artery occlusion

Occlusion of intracranial arteries by pituitary apoplexy with resulting infarction is a rare occurrence. A 50-year-old man who presented with a history of sudden onset of frontal headache and visual impairment was admitted to another medical centre and MRI revealed a non-enhancing sellar lesion with suprasellar and infrasellar extension. Thereafter, the patients consciousness deteriorated progressively and he showed signs of herniation; he was then referred to our centre for further evaluation. CT scanning revealed infarction of the left internal carotid artery territory. Transcranial resection of the tumour followed by a large decompressive craniotomy restored the blood flow in the internal carotid artery. Histological examination revealed the tumour to be a pituitary adenoma that contained formed blood elements. The patients neurological status did not improve and he died on the ninth postoperative day despite vigorous treatment for controlling intracranial pressure. This case study documents a rare presentation of pituitary apoplexy that caused signs of raised intracranial pressure due to mechanical obstruction of an internal carotid artery with resulting infarction.

Comparison of prognostic scores and surgical approaches to treat spinal metastatic tumors: A review of 57 cases

Surgical treatment of metastatic spinal cord compression with or without neural deficit is controversial. Karnofsky and Tokuhashi scores have been proposed for prognosis of spinal metastasis. Here, we conducted a retrospective analysis of Karnofsky and modified Tokuhashi scores in 57 consecutive patients undergoing surgery for secondary spinal metastases to evaluate the value of these scores in aiding decision making for surgery. Comparison of preoperative Karnofsky and modified Tokuhashi scores with the type of the surgical approach for each patient revealed that both scores not only reliably estimate life expectancy, but also objectively improved surgical decisions. When the general status of the patient is poor (i.e., Karnofsky score less than 40% or modified Tokuhashi score of 5 or greater), palliative treatments and radiotherapy, rather than surgery, should be considered.

Trigeminal neuralgia caused by a pontine abscess: Case report

OBJECTIVE AND IMPORTANCE:Various intracranial abnormalities, including infectious conditions, may manifest as trigeminal neuralgia. CLINICAL PRESENTATION:A 33-year-old man presented with a 15-day history of right-sided facial pain and numbness. Neurological examination revealed diminished corneal reflex and facial sensation in the right V1–V2 distribution. Magnetic resonance imaging revealed a contrast-enhancing lesion centered at the right pons with extension of the enhancement to the sphenoid sinus. INTERVENTION:Broad-spectrum antibiotics were administered for 6 weeks. This resulted in alleviation of symptoms and resolution of the lesion as revealed by repeat magnetic resonance imaging. CONCLUSION:Presentation of a pons abscess with trigeminal neuralgia is rare, and to the best of our knowledge has not been reported previously. The patient was treated successfully with antibiotics alone.

Effects of cross-linked high-molecular-weight hyaluronic acid on epidural fibrosis: experimental study.

OBJECT Epidural fibrosis is nonphysiological scar formation, usually at the site of neurosurgical access into the spinal canal, in the intimate vicinity of and around the origin of the radicular sheath. The formation of dense fibrous tissue causes lumbar and radicular pain. In addition to radicular symptoms, the formation of scar tissue may cause problems during reoperation. The authors aimed to investigate the effects of cross-linked high-molecular-weight hyaluronic acid (HA), an HA derivative known as HA gel, on the prevention of epidural fibrosis by using histopathological and biochemical parameters. METHODS Fifty-six adult female Sprague-Dawley rats were evaluated. The rats were divided into 4 groups. Rats in the sham group (n = 14) underwent laminectomy and discectomy and received no treatment; rats in the control group (n = 14) underwent laminectomy and discectomy and received 0.9% NaCl treatment in the surgical area; rats in the HA group (n = 14) received HA treatment at the surgical area after laminectomy and discectomy; and rats in the HA gel group (n = 14) underwent laminectomy and discectomy in addition to receiving treatment with cross-linked high-molecular-weight HA in the surgical area. All rats were decapitated after 4 weeks, and the specimens were evaluated histopathologically and biochemically. The results were statistically compared using the Mann-Whitney U-test. RESULTS Compared with the sham and control groups, the HA and HA gel groups showed significantly lower fibroblast cell density and tissue hydroxyproline concentrations (p < 0.05). There was statistically significant lower dural adhesion and foreign-body reaction between the control and HA gel groups (p < 0.05). Granulation tissue and epidural fibrosis were significantly lower in the HA and HA gel groups compared with the sham group (p < 0.05). There were no significant differences in any histopathological parameters or biochemical values between Groups 3 and 4 (p > 0.05). CONCLUSIONS Cross-linked high-molecular-weight HA had positive effects on the prevention of epidural fibrosis and the reduction of fibrotic tissue density. The efficacy of this agent should also be verified in further experimental and clinical studies.

Primary thoracolumbar Ewing's sarcoma presenting as isolated epidural mass

BACKGROUND CONTEXT Ewings sarcoma is the most common childhood malignancy of bone, but it rarely occurs as a primary extraosseous epidural tumor. PURPOSE To heighten awareness and treatment options of this rare (epidural) presentation of Ewings sarcoma. STUDY DESIGN Case report. METHODS Retrospective review. RESULTS We present a 13-year-old boy with progressive low back and bilateral lower extremity pain and normal neurologic examination. Magnetic resonance imaging showed an extradural tumor in the dorsal epidural space from T11 to L1. He underwent a posterior laminoplasty and gross total resection of tumor; histopathological diagnosis was consistent with Ewings sarcoma. After surgery, the patient underwent adjuvant chemotherapy and irradiation. At 10 months follow-up, the patient is neurologically intact without evidence of residual disease. CONCLUSIONS Ewings sarcoma of the epidural space should be considered in the differential diagnosis of epidural mass lesions. Because wide surgical margins cannot be obtained, close follow-up with a low threshold for reoperation is mandatory.

Biomechanical consequences of cervical spondylectomy versus corpectomy.

OBJECTIVE To evaluate the differences in spinal stability and stabilizing potential of instrumentation after cervical corpectomy and spondylectomy. METHODS Seven human cadaveric specimens were tested: 1) intact; 2) after grafted C5 corpectomy and anterior C4–C6 plate; 3) after adding posterior C4–C6 screws/rods; 4) after extending posteriorly to C3–C7; 5) after grafted C5 spondylectomy, anterior C4–C6 plate, and posterior C4–C6 screws/rods; and 6) after extending posteriorly to C3–C7. Pure moments induced flexion, extension, lateral bending, and axial rotation; angular motion was recorded optically. RESULTS After corpectomy, anterior plating alone reduced the angular range of motion to a mean of 30% of normal, whereas added posterior short- or long-segment hardware reduced range of motion significantly more (P < 0.003), to less than 5% of normal. Constructs with posterior rods spanning C3–C7 were stiffer than constructs with posterior rods spanning C4–C6 during flexion, extension, and lateral bending (P < 0.05), but not during axial rotation (P > 0.07). Combined anterior and C4–C6 posterior fixation exhibited greater stiffness after corpectomy than after spondylectomy during lateral bending (P = 0.019) and axial rotation (P = 0.001). Combined anterior and C3–C7 posterior fixation exhibited greater stiffness after corpectomy than after spondylectomy during extension (P = 0.030) and axial rotation (P = 0.0001). CONCLUSION Circumferential fixation provides more stability than anterior instrumentation alone after cervical corpectomy. After corpectomy or spondylectomy, long circumferential instrumentation provides better stability than short circumferential fixation except during axial rotation. Circumferential fixation more effectively prevents axial rotation after corpectomy than after spondylectomy.

Rod Migration to the Thoracic Subarachnoid Space after C1-2Instrumentation: A Case Report and Literature Review: Rod Migration after C1-2Instrumentation

Posterior instrumented fusion of the cervical spine is a common surgical procedure in the treatment of cervical subluxation, fractures, and stenosis. Although malpositions are commonly seen, it is rare to observe the malposition of the rod or interconnection because of hardware failure. A 62‐year‐old woman with spastic tetraparesis as a sequel to pediatric meningitis with C1–C2 cervical subluxation and myelomalacia had undergone laminectomy of C1 and C1 lateral mass and C2 bilateral pedicular screw fixation. Three years after the stabilization, she presented with complaints of headache, neck pain, and difficulty walking. There was no history of trauma during that period. A previously unrecorded and unusual migration of a rod through the thoracic subarachnoid space was detected. In this study, we report a case of atlantoaxial stabilization using the screw‐rod technique that was followed by rod migration to the thoracic subarachnoid space, and outline the subsequent management of the case. Failure of bony fusion can result in micromotion and subsequent migration of fixation device components. Routine radiographic follow‐up could be used to identify migration events.