Differentiation of Primary Central Nervous System Lymphoma and High-Grade Glioma with Dynamic Susceptibility Contrast-Derived Metrics: Pilot Study.

OBJECTIVE: Preoperative differentiation of lymphoma from other aggressive intracranial neoplasms is important as the surgical and adjuvant therapy may be fundamentally different between the 2 types of tumors. The purpose of this study was to assess the ability of the dynamic susceptibility contrast-derived metrics, percentage signal recovery (PSR) ratio, and relative cerebral blood volume (rCBV) to distinguish between primary central nervous system lymphoma (PCNSL) and high-grade glioma (HGG). METHODS: Twenty-six patients (15 with HGG and 11 with PCNSL) with histologically confirmed diagnoses were retrospectively analyzed. Mean PSR and rCBV were calculated from dynamic susceptibility contrast imaging. The 2 groups were compared using an independent samples t-test. Receiver operating characteristic analyses were performed to determine the area under the curve and identify threshold values to differentiate PCNSL from GBM. RESULTS: Both rCBV and PSR values were significantly different, at both the group level and subject level, between the PCNSL and HGG patients. The mean rCBV was significantly lower in PCNSL (1.38 ± 0.64) compared with HGG (5.19 ± 2.21, df = 11.24, P < 0.001). The mean PSR ratio was significantly higher in PCNSL (1.04 ± 0.11) compared with HGG (0.72 ± 0.16, df = 17.23, P < 0.001). An rCBV threshold value of 2.67 provided a 100% sensitivity and 100% specificity (area under the curve 1.0) for differentiating PCNSL from HGG. A PSR ratio threshold value of 0.9 was 100% sensitive and 90.91% specific for differentiating PCNSL from HGG. CONCLUSIONS: The findings of our study show that rCBV and PSR ratio are different in HGG and PCNSL at both the group level and subject level. Incorporation of perfusion in routine magnetic resonance imaging of contrast-enhancing lesions can have a significant impact on patient management.

Rare radiculopathy from an osteochondral loose body: a case report and literature review.

Lumbar radiculopathy is usually caused by nerve compression due to herniated disc material or compression by degenerative pathology such as enlarged facet joints, thickened ligamentum flavum or synovial cysts. We report the case of a 48-year-old female with L5 sciatica due to an osteochondral loose body in the foramen. This is only the third reported case of a single osteochondral loose body in the lumbar spine and the first reported case found in the foramen.

Clinical and radiological outcomes of image guided posterior C1-C2 fixation for atlantoaxial osteoarthritis (AAOA).

BACKGROUND: Atlantoaxial (C1-C2) osteoarthritis (AAOA) causes severe suboccipital pain exacerbated by lateral rotation. The pain is usually progressive and resistant to conservative therapy. Posterior fusion surgery is performed to stabilise the C1-C2 segment. This is the first Australian study reporting the outcome of posterior atlantoaxial fixation including hybrid fixations performed for AAOA. METHODS: All patients who underwent posterior atlantoaxial fixation surgery for AAOA from 2005 to 2015 at our institutions were enrolled (N=23). Patient demographics and surgical technique were recorded. These techniques included transarticular screw (TAS) fixation using image guidance with iliac crest bone graft and supplemental posterior Sonntag wiring, or C1-C2 lateral mass fixation (Harms technique). Some patients required a combination of fixation due to anatomical variation. Primary outcome measures including patient satisfaction, pain, disability scores and range of motion were recorded for all patients pre- and post-operatively. Post-operative assessment was supplemented with CT and X-ray imaging. RESULTS: Twenty-three patients (19 women, 4 males, mean age 71.8±6.3 years) underwent surgical fixation. Eight underwent TAS fixation, 8 had Harms fixation, and 7 had a hybrid fixation. All patients reported statistically significant improvement in pain scores [Visual Analogue Scale (VAS) 9.4 pre-op compared to 2.9 post-op, P<0.005]. Disability scores [Neck Disability Index (NDI)] were statistically significantly reduced from 72.2±12.9 pre-operatively to 18.9±11.9 post-operatively, P<0.005. Mean follow-up was 55.3±36.1 months. Results did not vary according to the construct type. Ninety-five point five percent of patients showed radiographic evidence of fusion. Ninety-one percent of patients said they would undergo the surgery again. CONCLUSIONS: Posterior atlantoaxial fixation with TAS and Harms constructs are highly effective for the surgical treatment of intractable neck pain secondary to atlantoaxial lateral mass osteoarthritis (AAOA). Surgery offers a high rate of symptom relief. If anatomical variability exists, both transarticular and pedicle screw fixation could be safely used in the same patient.

Multifocal intradural extramedullary anaplastic ependymoma of the spine.

Ependymomas are neuroectodermal tumours arising from the ependymal lining of the ventricles and central canal of the spinal cord. Intradural extramedullary (IDEM) ependymomas which are multifocal, and/or anaplastic (WHO grade III) at presentation are exceedingly rare. We present the second case of multifocal anaplastic IDEM ependymoma in the literature. A 47-year old female presented with left gluteal and thigh pain radiating to the groin associated with paraesthesiae. She had a normal neurological examination. Magnetic resonance imaging of the lumbar spine and subsequent magnetic resonance imaging (MRI) of the remaining neuroaxis demonstrated >10 lesions throughout cervical, thoracic and lumbosacral levels. There were no intracranial lesions. The patient initially underwent surgery for removal of three symptomatic lesions at S2. She recovered well. One year later she had further surgery for three progressing lesions at T5. Four of six lesions were WHO grade III. Two smaller nodules at T5 were WHO grade II. The patient had mild sensory disturbance over the right side of the trunk which resolved postoperatively. There were no long-term sequelae. The patient subsequently underwent full craniospinal irradiation using proton beam therapy. Due to their rarity, there are no guidelines for the management of multifocal IDEM ependymoma. The only previously published case of multifocal anaplastic IDEM ependymoma by Schuurmans et al. involved surgical resection and 20 cycles of whole-spine radiotherapy. Schuurmans patient unfortunately died two years post-diagnosis with progressive cranial metastases and post-radiation myelopathy. In our case, all remaining lesions are stable and she is neurologically intact at 48-month follow up.

An unusual radiological presentation of optic nerve sheath meningioma.

Our report describes an unusual radiological presentation of optic nerve sheath meningioma. The classic radiological appearance of optic nerve thickening with enhancement and calcification within the tumor was not seen; instead, an elongating gadolinium enhancing band-like area adjacent to the superomedial aspect of the left optic nerve sheath was identified. The diagnosis was confirmed on histopathology. Our report adds to the spectrum of presentations of this relatively common clinical entity.

Accuracy of percentage of signal intensity recovery and relative cerebral blood volume derived from dynamic susceptibility-weighted, contrast-enhanced MRI in the preoperative diagnosis of cerebral tumours.

Conventional magnetic resonance imaging (MRI) is the technique of choice for diagnosis of cerebral tumours, and has become an increasingly powerful tool for their evaluation; however, the diagnosis of common contrast-enhancing lesions can be challenging, as it is sometimes impossible to differentiate them using conventional imaging. Histopathological analysis of biopsy specimens is the gold standard for diagnosis; however, there are significant risks associated with the invasive procedure and definitive diagnosis is not always achieved. Early accurate diagnosis is important, as management differs accordingly. Advanced MRI techniques have increasing utility for aiding diagnosis in a variety of clinical scenarios. Dynamic susceptibility-weighted contrast-enhanced (DSC) MRI is a perfusion imaging technique and a potentially important tool for the characterisation of cerebral tumours. The percentage of signal intensity recovery (PSR) and relative cerebral blood volume (rCBV) derived from DSC MRI provide information about tumour capillary permeability and neoangiogenesis, which can be used to characterise tumour type and grade, and distinguish tumour recurrence from treatment-related effects. Therefore, PSR and rCBV potentially represent a non-invasive means of diagnosis; however, the clinical utility of these parameters has yet to be established. We present a review of the literature to date.

Surgical treatment of cervical disc protrusion causing intracranial hypotension following chiropractic manipulation.

We describe a woman with intracranial hypotension provoked by a combination of calcified disc protrusion and chiropractic manipulation who required surgical intervention for definitive treatment. Intracranial hypotension is a rare but increasingly well recognized cause of orthostatic headache that arises due to spinal cerebrospinal fluid leakage from meningeal diverticula or dural perforations.

Spontaneous pineal apoplexy in a pineal parenchymal tumor of intermediate differentiation.

Pineal apoplexy is a rare clinical presentation of pineal parenchymal tumors. We report the curative treatment of a case of pineal parenchymal tumor of intermediate differentiation with spontaneous apoplectic hemorrhage. This case is shown through computed tomography and magnetic resonance imaging of the brain, and is confirmed via histopathological studies. Recurrent upward gaze paresis was observed after the stereotactic biopsy. The paresis required an expeditious tumor resection. The mechanism of the pineal apoplectic hemorrhage remains unclear although it has been observed in different pineal region lesions. Clinical and radiological evidence of the cure 5 years post-surgery is available.