Search PubMed⌕ Search

Biomedical subjects

J Ransohoff

Publications and source records attributed to J Ransohoff.

At least 181 records · Page 10Linked to original sources
PubMed1971

Ergonomic evaluation of a redesigned surgical instrument.

Some problems have been encountered with the current design of the bayonet forceps, one of the more frequently used instruments of the neurosurgeon. By studying its function and operational use, a new design was conceived to make the instrument more amenable to the surgeon's hand, ie ergonomically suitable. This was tested in the laboratory and the operating room, and was found superior to the old one in comfort, stability-in-use, and ease of operation. This method of ergonomic redesign and evaluation can be used for other similar problems.

Journal Article↗
PubMed1971

Spontaneous canine hydrocephalus: cerebrospinal fluid dynamics.

Cerebrospinal fluid dynamics were studied in 14 dogs with spontaneous hydrocephalus. In nine of the dogs aqueductal obstruction was observed and the remainder had a `communicating type' hydrocephalus. The major histological findings consisted of severe ependymal destruction, spongy changes in the periventricular white matter, increased density of capillaries in this area, and varying degrees of thickening, fibrosis, and fusion of the choroid villi. The formation and absorption of CSF were studied by perfusion of the cerebral ventricles. The rate of formation of CSF was found to decrease with perfusion pressure by V(f) = 0·02595-0·00022 P ml./min (P = pressure in cm H(2)O). The absorption of spinal fluid was found to increase linearly with pressure by V(a) = 0·0165 + 0·00050 P. The various factors influencing the formation and absorption of the spinal fluid are discussed. The meaning and attainment of `arrest' of the hydrocephalic process in terms of the measured rates of CSF formation and absorption in these animals are considered.

Animals↗