Disappearance of phantom pain after focal brain infarction

A patient with hemiplegia and hemihypoesthesia is presented in whom preexisting phantom limb pain disappeared with the appearance of a stroke localized by CT scan to the posterior internal capsule. Differentiation between the cutaneous sensation and the sensation of phantom limb pain that appeared later seems to support the assumed existence of a polysynaptic sensory pathway that conveys the sensations of deafferentation.     

Isradipine prevents global and regional cocaine-induced changes in brain blood flow: a preliminary study

The L-type calcium channel antagonist, isradipine, reduces brain ischemia in animal models of ischemic stroke. These effects of isradipine appear more pronounced in dopamine (DA) rich brain regions. These same DA-rich brain regions have also been shown to be the areas most affected by cocaine-induced ischemic changes. Using a novel quantified approach to single photon emission computerized tomography, we demonstrated that isradipine pre-treatment prevented cocaine-induced ischemic changes, especially in these DA-rich brain regions. This is the first demonstration that any medication, including isradipine, can prevent the ischemic effects of cocaine on brain blood flow. Isradipine may, therefore, be a useful therapeutic agent for the prevention of brain ischemia in cocaine addicts. Received: 4 June 1997/Final version: 3 November 1997     

Angiodysplasia of the right colon treated by embolization with ivalon (polyvinyl alcohol)

Angiodysplasia of the colon is being recognized with increasing frequency as a source of lower gastrointestinal bleeding in the elderly. In one patient with colonic angiodysplasia, superselective segmental embolization of the ileo-colic artery with Ivalon resulted in the cessation of bleeding without causing bowel infarction. However, because of the development of collateral branches to the angiodysplastic malformation, bleeding recurred. While colectomy remains the treatment of choice in younger patients, in high risk patients embolization with a permanent embolic material, such as Ivalon, is an attractive alternative.     

Abnormal ultrastructural appearances in axons of feline pericruciate cortex after lateral funiculotomy

Summary Following left lateral funiculotomy, axons of cat pericruciate cortex exhibited neurofilamentous hyperplasia and complex, adaxonal, oligodendrocytic invaginations into electron-lucent or (commonly) electron-dense, degenerating axoplasm. These changes were absent from sham-operated and unoperated animals. Neurofilamentous hyperplasia was exclusively right-sided and appeared in myelinated axons 5–49 days postoperatively and in nonmyelinated axons 14–153 days after surgery. Oligoglial invaginations were present 1–49 days after surgery and were predominantly right-sided.Intramyelinic, axo-dendritic synapses appeared in operated cats 5–10 days postoperatively. Intra-axonal accumulations of ribosomes were found also. These changes also occurred exclusively or predominantly contralateral to spinal surgery.Other ultrastructural abnormalities, e.g., amorphous transformation of axoplasm and accumulations of dense bodies in intra-myelinic, dark cytoplasm, had a less certain relationship to lateral funiculotomy.The axonal alterations that were limited to operated cats possibly represent a true retrograde axonal degeneration occurring at a distance from the site of axonic interruption and unaccompanied by evidence of nerve cell death.This work was supported by the Medical Research Service of the Veterans Administration and by the National Institutes of Health Research Grant NS-08735     

The effect of light deprivation on the progress of retinal degeneration in two strains of dystrophic rat.

The effects of light deprivation on the retina and visual cortex of albino dystrophic and pigmented dystrophic rats have been investigated. Light deprivation retarded retinal degeneration (as assessed histologically and by nucleic acid measurements) in the former but had no significant effect on the latter. Similarly the changes in visual cortex nucleic acid content accompanying retinal degeneration were reduced in the albino dystrophic strain but not in the pigmented dystrophic strain.     

Intramedullary pressure patterns

The insertion of cement and femoral prosthesis in total hip replacement produces biochemical abnormalities. These are thought to be caused by a marked rise in intramedullary pressure. Surgeons aim to reduce these pressures by using different methods of insertion and venting. The present investigation was undertaken to establish if any one method was superior to the others. The greatest modification of acrylic pressure was obtained by means of a drill hole. Thie highest rise in pressure was produced by the insertion of the femoral prosthesis and this was little modified by any of the alternatives of the use of a 3/16 inch drill hole, a 16-gauge catheter, and cement gun.     

Pretreatment with chemotherapy in patients with advanced head and neck cancer

Average survival for advanced head and neck cancer (AHNC) is 18 months. In an attempt to improve this we treated 29 AHNC patients between 1978-82 with two courses of chemotherapy. Chemotherapy consisted of cyclophosphamide, methotrexate, 5 fluorouracil and bleomycin; or bleomycin, cisplatinum and methotrexate. Chemotherapy was given prior to definitive therapy of radiotherapy or radiotherapy and surgery. All patients were stage 3 or 4. All patients were Eastern Co-operative Oncology Group status performance 0 or 1. Response to chemotherapy did not improve survival. Pretreatment with chemotherapy should be investigational until increased survival has been documented.