Jonathan Lucas

Evaluation of (18)fluorodeoxyglucose positron emission tomography ((18)FDG PET) in the detection of malignant peripheral nerve sheath tumours arising from within plexiform neurofibromas in neurofibromatosis 1

OBJECTIVES The ability of 18fluorodeoxyglucose positron emission tomography (18FDG PET) to detect malignant change in plexiform neurofibromas from patients with neurofibromatosis 1 (NF1) was evaluated. METHODS Eighteen NF1 patients who presented with pain, increase in size, or neurological deficit associated with a plexiform neurofibroma were assessed. Magnetic resonance imaging determined the site and extent of the lesion. Qualitative18FDG PET was performed and the standard uptake value (SUV) measured the regional glucose metabolism. Histological confirmation of the diagnosis was obtained in 10 patients. RESULTS Twenty three plexiform neurofibromas were detected in 18 patients. Seven malignant peripheral nerve sheath tumours, four high grade and three low grade tumours, occurred in five patients. In one patient the clinical and radiological characteristics of the tumour suggested malignancy, but histology was inconclusive. Fifteen benign plexiform neurofibromas were identified in 12 patients and these findings were confirmed histologically in five lesions from four patients. Ten plexiform neurofibromas occurring in eight patients were considered benign on18FDG PET and the patients did not undergo surgery. They remained stable or their symptoms improved on clinical follow up (median 9 months). The results of qualitative 18FDG PET were interpreted as indicating that 13 plexiform neurofibromas were benign and 10 were malignant. No malignant tumours were classified as benign, but two benign tumours were reported as malignant. The SUV was calculated for 20 tumours and was significantly higher in five malignant tumours 5.4 (SD 2.4), than in 15 benign tumours 1.54 (SD 0.7), p=0.002. There was an overlap between benign and malignant tumours in the SUV range 2.7–3.3. CONCLUSIONS 18FDG PET is helpful in determining malignant change in plexiform neurofibromas in NF1. Increased separation between benign and malignant lesions could be obtained by calculating the SUV at about 200 minutes after injection of 18FDG, when the peak activity concentration is obtained in malignant tumours.

Hematogenous methicillin-resistant Staphylococcus aureus spondylodiscitis.

Study Design. Retrospective case series. Objective. To determine relevant demographics, clinical presentations, and outcomes of this condition. Summary of Background Data. This is the first study looking specifically at methicillin-resistant Staphylococcus Aureus (MRSA) spondylodiscitis. Methods. We performed a retrospective review of patients presenting between 2000 and 2005. Results. Thirteen cases were identified. The mean age was 65 years; 85% were male. All cases presented with back pain, spinal tenderness, and systemic upset. Neurologic deficit was present initially in 39%, and 8% developed neurologic deterioration during treatment. The thoracic spine (53%) was most commonly affected, followed by the lumbar (33%), thoracolumbar junction (7%), and cervical spine (7%); 16% of cases were multilevel. The white cell count, erythrocyte sedimentation rate and C-reactive protein were elevated in all cases with means of 17.3 × 10−9/L, 102 mm/h, and 236 mg/L, respectively. Radiologic diagnosis was established with MRI in all cases. The most common risk factors were diabetes mellitus (62%), malnourishment (54%), cirrhosis (31%), end-stage renal failure (15%), and intravenous drug use (15%). Multiple risk factors were present in 76% of cases, and only 15% had no identifiable risk factors. The main sources of sepsis were intravenous catheters (23%), urinary tract (15%), and intravenous drug use (15%). Treatment consisted of intravenous vancomycin monotherapy for a mean period of 4 weeks followed by oral combination or monotherapy antimicrobials for a mean period of 8 weeks. Operative intervention was required in 38% of cases. At 6 months, 54% of cases were clinically free of infection, 38% had died, and 8% required ongoing treatment. Neurologic deficit was present in 50% of survivors. At 1 year, 29% of survivors had MRSA bacteremia and spondylodiscitis recurrence. Conclusion. This is a devastating condition with high mortality and morbidity.

Fluorodeoxyglucose PET in the evaluation of amputations for soft tissue sarcoma.

The aims of this study were to evaluate the uptake of fluorodeoxyglucose (FDG) in the stumps of patients who have had amputations for soft tissue sarcoma and assess its utility in identifying local recurrence of disease. Sixteen patients who had either an upper or a lower limb amputation were evaluated. FDG PET scans (half body scans to the stump +/- local emission transmission views of the stump) were performed as part of their routine follow-up for evidence of metastases over a number of years (mean = 2.6 years; range 0.25-8 years). Diffuse uptake was found in 10 stumps for up to 18 months post-surgery without any evidence of disease recurrence. Focal areas of uptake were associated with known pressure areas with skin breakdown that could be seen clinically. In the absence of localized clinical changes, these areas represented a recurrence and needed a biopsy.

10 kHz High-Frequency Spinal Cord Stimulation for Chronic Axial Low Back Pain in Patients With No History of Spinal Surgery: A Preliminary, Prospective, Open Label and Proof-of-Concept Study.

To explore the effectiveness of 10 kHz high frequency spinal cord stimulation (HF10 therapy) treatment of chronic low back pain in patients who have not had spinal surgery.

Spinal cord compression by a solitary metastasis from a low grade leydig cell tumour: a case report and review of the literature

BackgroundLeydig tumour is rare and there are only three cases with metastatic disease reported.Case presentationA 52 year-old Caucasian male was admitted, on emergency basis to the Orthopaedic Department with six weeks history of increasing midthoracic back pain, change in gait, poor balance, subjective weakness and numbness of the lower trunk and legs. MRI scan showed change in the signal intensity of T4 and T5 vertebral body but their height were maintained. Urgent T4 and T5 corpectomies, decompression of the spinal cord and reconstruction of the vertebral bodies were performed followed by radiotherapy. Neurological status significantly improved with a mild residual numbness over the dorsum of the right foot. The histology of the excised tumour was identical to the primary. At 2 years follow-up visit the patient is neurologically stable and disease free without other organs metastases.ConclusionThis is the first case in English literature, which shows that spinal metastases could occur even in the early stage of Leydig cell tumour, without other organs involvement. Aggressive surgical management of spinal metastases combined with post operative radiotherapy can give a better chance for long survivorship.

Long-Term Improvements in Chronic Axial Low Back Pain Patients Without Previous Spinal Surgery: A Cohort Analysis of 10-kHz High-Frequency Spinal Cord Stimulation over 36 Months

Objective This prospective, open-label study was designed to evaluate the long-term effectiveness of 10-kHz high-frequency spinal cord stimulation (SCS) in the treatment of chronic axial low back pain with no history of spinal surgery. Methods Patients with chronic low back pain without previous spinal surgery underwent assessment by a multidisciplinary pain and surgical team to confirm eligibility. After a successful temporary trial of 10-kHz HF-SCS therapy, defined by ≥50% back pain reduction, enrolled subjects underwent permanent system implantation and were followed up for 36 months. Outcome measures consisted of a 100-mm visual analog scale (VAS) for pain intensity, the Oswestry Disability Index (ODI), and a standard measure of health-related quality of life. Results Twenty-one patients satisfied the inclusion/exclusion criteria. Following a temporary trial, 20 of 21 (95%) subjects were implanted with a pulse generator, and 17 of 20 reached the 36-month time point. From baseline to 36 months, the average VAS pain intensity decreased from 79 ± 12 mm to 10 ± 12 mm, the average ODI score decreased from 53 ± 13 to 19.8 ± 13, and use of opioids decreased from 18 subjects to two subjects. One subject was deceased, unrelated to the study, one subject was explanted due to loss of effectiveness, and one subject was lost to follow-up. Conclusions These results suggest that 10-kHz high-frequency SCS may provide significant, long-term back pain relief, improvement in disability and quality of life, and reduction in opioids for nonsurgical refractory back pain.

Neuromuscular scoliosis as a sequelae of Guillain-Barre syndrome

The neuromuscular sequaelae of Guillain-Barré syndrome are well documented in the literature. Persistent distal muscular weakness and loss of peripheral limb reflexes are common in those affected. We report a case of a 14-year-old boy who developed the Miller-Fisher variant of Guillain-Barré syndrome at the age of 8 years. Six years after the acute episode, he had persistent lower limb areflexia and mild weakness. He had also developed a neuromuscular scoliosis. The scoliosis was successfully treated with posterior instrumentation and fusion surgery. Neuromuscular scoliosis is rare following Guillain-Barré syndrome, with no previous reports associated with the Miller-Fisher variant that we are aware of. When evaluating patients post Guillain-Barré syndrome, structural spinal examination is essential to identify rare deformity that may need surgical correction.

Fifteen-minute consultation: neuromuscular spinal deformity in disabled children

Spinal deformity is common and occasionally inevitable in children with disabilities. This article concentrates on non-ambulant children with a spinal deformity, and aims to help the paediatrician understand the challenges families and spinal surgeons face.