Articles: sciatic-neuropathy-pathology.
-
Case Reports
Gluteal muscular and sciatic nerve metastases in advanced urinary bladder carcinoma: case report.
We present a case of gluteal muscular and sciatic nerve metastases from urinary bladder carcinoma. T2-weighted magnetic resonance images demonstrated diffuse swelling and an increase in the signal of the right gluteus maximus muscle without destruction of the original arrangement of muscular fibers. ⋯ Fine-needle aspiration biopsy with ultrasonographic guidance confirmed metastatic carcinoma cells in the right gluteal muscle and the sciatic nerve. These radiologic findings may represent a rare pattern of metastasis from urinary bladder carcinoma.
-
Peripheral nerve injury leads to structural and functional changes in the spinal dorsal horn, and these are thought to be involved in the development of neuropathic pain. In the chronic constriction injury (CCI) model, abnormal 'dark' neurons and apoptotic nuclei have been observed in laminae I-III of the dorsal horn in the territory innervated by the injured sciatic nerve. These findings have been taken as evidence that there is significant neuronal death in this model, and it has been suggested that loss of inhibition resulting from death of GABAergic inhibitory interneurons contributes to the neuropathic pain. ⋯ All of the CCI animals showed clear signs of thermal hyperalgesia. However, the numbers of neurons in laminae I-III of the ipsilateral dorsal horn in these animals did not differ significantly from those on the contralateral side, nor from those of sham-operated or naïve animals. These results do not, therefore, support the suggestion that there is significant neuronal death in the dorsal horn in this model.
-
Experimental neurology · Jul 2004
MRI of peripheral nerve degeneration and regeneration: correlation with electrophysiology and histology.
Acute axonal nerve lesions cause a hyperintense signal on T2-weighted (T2-w) magnetic resonance imaging (MRI) at the nerve lesion site and distal to it. The aim of this experimental study was to investigate the spatiotemporal evolution and resolution of MR nerve signal changes following denervation and reinnervation, and to relate these findings to electrophysiology and histology. The proximal sciatic nerve of adult rats was ligated by a tight suture that was removed 1 week later to induce complete axotomy and nerve regeneration upon release. ⋯ MR signal alterations occur as early as 24 h after an axonal nerve lesion and correlate with nerve fiber degeneration and later with nerve oedema on histology. MR findings in denervation and reinnervation parallel the electrophysiological changes. Thus, MRI is a promising diagnostic tool for the early detection of acute axonal nerve lesions and monitoring of nerve regeneration.
-
Clinical Trial
Piriformis syndrome: anatomic considerations, a new injection technique, and a review of the literature.
Piriformis syndrome can be caused by anatomic abnormalities. The treatments of piriformis syndrome include the injection of steroid into the piriformis muscle and near the area of the sciatic nerve. These techniques use either fluoroscopy and muscle electromyography to identify the piriformis muscle or a nerve stimulator to stimulate the sciatic nerve. ⋯ Anatomic abnormalities causing piriformis syndrome are rare. The technique used in the current study was successful in injecting the medications near the area of the sciatic nerve and into the piriformis muscle.