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OBJECTIVES: To investigate the effect of cervical spondylosis (CS) in the brain with a combination of advanced neuroimaging techniques. METHODS: Twenty-seven patients with CS and 24 age- and gender-matched healthy controls were studied. Disease severity was quantified using the Modified Japanese Orthopaedic Association Scoring System (mJOHA). Magnetic resonance (MR) imaging of the brain and spinal cord, functional MR imaging (fMRI) with a bilateral rest/finger-tapping paradigm, brain diffusion tensor imaging (DTI), voxel-based morphometry (VBM), and MR spectroscopy of the sensorimotor cortex were performed. RESULTS: A total of 92.3% of patients had more than one herniated disc. In the MRI, 33.33% presented signs of myelopathy. The mJOHA score was 13.03 ± 2.83. Compared with controls, DTI results showed significant lower FA values in Corpus callosum, both corticospinal tracts and middle cerebellar peduncles (p < 0.05 corrected). Only in CS patients fMRI results showed activation in both globus pallidi, caudate nucleus, and left thalamus (p < 0.001). Subject-specific activation of the BOLD signal showed in CS patients lower activation in the sensorimotor cortex and increased activation in both cerebellum hemispheres (p < 0.05 corrected). VBM showed bilateral clusters of gray matter loss in the sensorimotor cortex and pulvinar nucleus (p < 0.05 corrected) of CS patients. NAA/Cr was reduced in the sensorimotor cortex of CS patients (p < 0.05). Linear discriminant and support vector machine analyses were able to classify > 97% of CS patients with parameters obtained from the fMRI, DTI, and MRS results. CONCLUSION: CS may lead to distal brain damage affecting the white and gray matter of the sensorimotor cortex causing brain atrophy and functional adaptive changes. KEY POINTS: • This study suggests that patients with cervical spondylosis may present anatomical and functional adaptive changes in the brain. • Cervical spondylosis may lead to white matter damage, gray matter volume loss, and functional adaptive changes in the sensorimotor cortex. • The results reported in this work may be of value to better understand the effect of prolonged cervical spine compression in the brain.

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OBJECTIVE: To evaluate the usefulness of diffusion tensor imaging (DTI) in the clinical setting as a complementary tool to conventional MRI in the study and assessment of the sciatic nerve and its pathologies. METHODS: 17 patients diagnosed with different types of sciatic neuropathy and 10 healthy controls underwent a conventional MRI and a DTI study in a 3-T MR scanner (Achieva(®) 3-T X-Series; Philips Healthcare, Netherlands). RESULTS: In the control group, we were able to track and visualize the common sciatic nerve and its main branches from hip to foot. In the patient group, the affected sciatic nerves presented statistically significant lower fractional anisotropy values and higher apparent diffusion coefficient values when compared with controls, suggesting nerve damage. In all cases, DTI offered complementary information for diagnosis and/or confirmation of the suspected pathology. When compared with conventional MRI, DTI showed higher sensitivity for nerve damage detection. CONCLUSION: DTI offers a significant improvement and an important complement to visualize the sciatic nerve and its main branches. In patients with sciatic nerve pathology DTI allows to a better detection and characterization of the nerve damage. ADVANCES IN KNOWLEDGE: DTI enables in vivo dissection of the sciatic nerve white matter fibres; its use offers a significant improvement and complement to conventional MRI.

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Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is a recently defined inflammatory central nervous system disorder responsive to steroids with characteristic magnetic resonance imaging (MRI) features. We report a 69-year-old man presenting with gait ataxia with the characteristic MRI features of CLIPPERS and describe the clinical, MRI, and magnetic resonance spectroscopy (MRS) follow-up after treatment with glucocorticosteroids. Brain and spine MRI showed punctate enhancement peppering the brainstem, cerebellar peduncles, and upper cervical cord. In MRS, the ratio of N-acetyl aspartate to creatine (NAA/Cr) was significantly decreased in the pons and both thalami. An extensive evaluation found no alternative diagnoses. Treatment with steroids led to rapid clinical improvement. Repeat MRI and MRS showed complete resolution of gadolinium-enhancing lesions and recovery of NAA/Cr levels in the pons and thalami. After 1 month of tapering oral steroids, weekly oral methotrexate was started and the patient has remained stable for the past 6 months.

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BACKGROUND AND PURPOSE: Intracranial epidermal cysts are benign uncommon lesions. Such lesions arise from an inclusion of an ectodermal element during neural tube closure, in which dermal elements become trapped in the suture line, diploe, meninges, or scalp. Reports have extensively demonstrated the typical magnetic resonance (MR) spectra with the presence of large lactate signals with a virtual absence of healthy brain metabolites. METHODS: A 20-year-old male patient with a parietal lobe brain lesion was studied by magnetic resonance imaging and magnetic resonance spectroscopy in a 1.5-T Philips scanner. RESULTS: The lesion presented atypical MR spectra with presence of alanine (1.46 ppm), lactate (1.31 ppm), and amino acids such as valine, isoleucine (0.97 ppm), and glicine (3.52 ppm). No evidence of normal parenchyma tissue metabolites (N-acetylaspartate, creatine, and choline) or succinate and acetate signals was observed. This spectral pattern was unexpected being proposed the differential diagnosis of brain abscess versus epidermoid cyst. Finally, surgical total excision biopsy confirmed the diagnosis of epidermal cyst. CONCLUSIONS: In this report, we describe a case of an epidermal cyst with an unusual metabolic pattern observed by magnetic resonance spectroscopy mimicking a brain abscess.

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Los ependimomas constituyen la neoplasia más frecuente de la médula espinal. Se desarrollan a partir de células que revisten el canal ependimario. Un subtipo infrecuente es el ependimoma de células gigantes, del que se han descrito solo 8 casos en dicha localización. Describimos el caso de un varón de 42 años con lumbalgia de varios meses de evolución. La RMN mostró un tumor bien circunscrito intradural en L1, que se resecó en su totalidad. El estudio histológico demostró proliferación fusocelular de distribución perivascular con formación de pseudorrosetas y moderada atipia citológica con células gigantes multinucleadas. El estudio inmunohistoquímico confirmó el diagnóstico de ependimoma de células gigantes(AU)

Ependymomas are the most frequent neoplasms of the spinal cord, arising from the cells lining the spinal canal. Among them, giant cell ependymoma is a rare subtype with only 8 cases previously reported to date. We present a further case in a 42-year-old man who presented with a history of lower back pain for several months. The MRI revealed a well-circumscribed interdural mass at L1. The tumour was totally resected and histologically it was seen to be comprised of a proliferation of fusiform cells arranged in a perivascular pattern with pseudorosettes and cytologic atypia with multinucleated giant cells. Immunohistochemistry confirmed the diagnosis of giant cell ependymoma(AU)

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OBJECTIVES: To evaluate the sensitivity and specificity of serum tissue polypeptide antigen (TPA) as a tumor marker for monitoring tumor recurrence in a prospective Phase II study. METHODS: This study consisted of 421 subjects allocated to three groups: 241 patients treated for bladder cancer between 1991 and 1995, 126 subjects with a previous history of bladder tumor but with no recurrence at the time of study enrollment, and 54 healthy volunteers. Soluble TPA concentrations were measured by radioimmunoassay. RESULTS: On the basis of receiver operating characteristic plot analysis, the normal test threshold was set at 63 U/L. For bladder cancer detection, the TPA specificity was 73% and sensitivity was 45%. TPA levels correlated with tumor stage (P <0.01), histologic grade, nodal stage, and metastatic stage and with urinary cytology in univariate analysis. In the subsets of patients with a history of bladder cancer and normal TPA levels, 34.9% experienced a relapse compared with 37.5% of patients with elevated TPA levels (no statistically significant difference). Among the patients with normal TPA levels who experienced recurrence, the mean disease-free interval was 30.6 months compared with 25.1 months in patients with elevated TPA levels (no statistically significant difference). Multivariate analysis showed that TPA was not an independent prognostic biomarker for tumor relapse. CONCLUSIONS: In patients with bladder cancer, the TPA serum level correlated with initial tumor stage and grade, but it was not useful for detecting or monitoring relapses.

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