Thermosensitive determination of patency in lumboperitoneal shunts. Technical note.

Surface cooling and thermistor recording over shunt tubing was used in 23 studies of cerebrospinal fluid shunt patency in 19 patients with lumboperitoneal shunts and normal-pressure hydrocephalus. Shunt patency was shown by downward reflection of the recording trace similar to that obtained for ventriculoperitoneal shunts. Obstruction was demonstrated by a flat-line recording or an upward deflection.