Sciatica management: chemonucleolysis vs. surgical discectomy.

True sciatica, and the back pain associated with it, are symptoms stemming from a common anatomical lumbar distortion--compression of a spinal nerve root. Two therapeutic approaches have evolved: surgical laminectomy and discectomy for relief of compression of a lumbar nerve root; and chemonucleolysis, a tissue modification technique using the intradiscal injection of the proteolytic enzyme chymopapain. Chemonucleolysis has been demonstrated to have a successful outcome at the 75% level in 6 weeks and at the 80% level in 6 months. Lumbar microdiscectomy appears to be 85% effective at 3 months.

Sciatica--management by chemonucleolysis versus surgical discectomy.

Two therapeutic approaches designed specifically to relieve the symptoms of sciatica and resolve the signs of lumbar radiculopathy brought about by herniation of the nucleus pulposus have evolved. The surgical removal of the lumbar disc is an operation which has undergone miniaturization in recent years. Treatment of disc hernia by chemical hydrolysis of the nucleus pulposus (chemonucleolysis) has, over the past 20 years, become an alternative to open surgical treatment. These two forms of therapy are compared as to their efficacy and safety. Neurosurgeons now have the data to decide on the suitability of employing one or the other (or both) of these forms of treatment in the care of patients with intractable sciatica.

Relaxation of bovine, porcine and human brain arteries by parathyroid hormone.

We have studied the relaxant effect of bovine parathyroid hormone (bPTH) on helical strips of branches of bovine and human middle cerebral arteries and bovine and porcine basilar arteries. All arteries were studied after contraction with prostaglandin (PG) F2 alpha or KCl. In the case of all arteries contracted with PGF2 alpha, the ED50 of PTH vasorelaxation related to maximal vasorelaxation induced by papaverine ranged from 9 to 14 nM for bPTH-(1-34) and 100 to 220 ng/ml for native bPTH-(1-84). The PTH inhibitor, [Nle8, Nle18, Tyr34]bPTH-(3-34) amide, attenuated the vasorelaxant effect of both bPTH-(1-34) and bPTH-(1-84). The vasorelaxant effects of PTH which we have observed in this study are consistent with the stimulatory effects of PTH on vascular adenylate cyclase which we had previously reported.

Acromegaly with an adenomatous pharyngeal pituitary.

A patient with acromegaly was found to have a discrete adenoma of the pharyngeal pituitary lodged within the sphenoid sinus. Removal of this adenoma, believed to be complete, did not normalize the growth hormone secretion. At the time of surgery, inspection and biopsy of the pituitary gland failed to disclose the presence of any identifiable intrasellar adenoma; one year later, however, definite radiological changes indicated the presence of an intrasellar mass. The underlying pathophysiology in this patient may have been due to diffuse hyperplasia of hypersecreting nonsuppressible somatotrophs, with adenoma formation secondary to the hyperplasia.