Neurosurgery
-
Comparative Study
Reduction of post-traumatic intracranial hypertension by hypertonic/hyperoncotic saline/dextran and hypertonic mannitol.
Cerebral injury is seen in one of three patients with multiple traumas; thus efficient shock treatment is a most important measure against the development of secondary brain damage. Small-volume resuscitation in severe hemorrhagic shock by hypertonic/hyperoncotic saline/dextran has been shown to instantaneously normalize cardiac output and to raise systemic blood pressure. In this study, the fluid regimen was compared with hypertonic mannitol to investigate their therapeutic efficacy in intracranial hypertension. ⋯ The increase of the cerebral water content of the traumatized hemisphere was associated with a respective increase of the cerebral Na+ content and a (nonsignificant) decrease of the K+ content. The present findings demonstrate that the hypertonic/hyperoncotic saline/dextran was as efficient as the mannitol in reducing ICP that had been increased by a cerebral lesion and a space-occupying mass; the underlying mechanisms responsible for the reduction might differ. Because of the powerful hemodynamic properties of the saline/dextran in circulatory shock, administration of the solution in patients with multiple traumas and head injury might be particularly advantageous for the prevention of secondary ischemic brain damage.
-
Neurosurgery at the University of Michigan was established as a specialty three-quarters of a century ago by Max Minor Peet. It developed under the successive leadership of Edgar Allan Kahn, Richard Coy Schneider, and Julian T. ⋯ Each has made unique contributions to the program, which has a strong tradition of teaching, research, and patient care. This article traces the development of the training program in neurosurgery at Michigan, focusing on its historical background, past accomplishments, present structure, and future directions.
-
The possibility that the female sex steroid progesterone plays a role in meningioma proliferation has been suggested by a number of investigators, and it has been shown that many meningiomas have high-affinity progesterone binding sites. There has been a long-standing debate in the literature as to whether the progesterone receptors that are present in meningiomas are functional. We recently showed, by the use of immunohistochemistry, that the progesterone receptor in meningiomas is localized to the nucleus, suggesting that the receptor is in a location to be activated. ⋯ In all meningioma cell cultures, an increase in the transcription of the progesterone response element construct was observed in the presence of dexamethasone, suggesting that the glucocorticoid receptor in meningiomas is functional. An increase in transcription was observed with the addition of promegestone (R5020), a progesterone agonist, only in meningioma cell cultures that were expressing the progesterone receptor. These data show that both the progesterone and the glucocorticoid receptor in meningiomas are functional and support the concept that progestins and glucocorticoids may play an important role in meningioma growth.
-
Infantile myofibromatosis is a rare clinical entity characterized by multiple mesenchymal tumors in the neonatal period. We describe a 15-month-old girl with multicentric cranial lesions involving the parietal and occipital bones associated with a single small subcutaneous lesion in the back. ⋯ This is the first description of magnetic resonance features of multicentric infantile myofibromatosis in the cranium, and gadolinium-enhanced magnetic resonance images were useful in showing dural involvement. The importance of recognizing this disorder is emphasized because of its special clinical behavior.
-
Comparative Study
Clinical evaluation of a miniature strain-gauge transducer for monitoring intracranial pressure.
In 25 patients, we evaluated the accuracy of a new miniature strain-gauge transducer developed for the measurement of intracranial pressure (ICP). The ICP in each patient was measured with the intraventricular, miniature strain-gauge transducer, and that value was compared with the ICP measured with a ventriculostomy catheter coupled to an external strain-gauge transducer. From the two monitors, 2218 simultaneous measurements of ICP were obtained. ⋯ The two values for the ICP were within 2 mm Hg of each other on 63% of the measurements and within 4 mm Hg of each other on 89% of the measurements. The average zero drift of the miniature strain-gauge transducer, measured at ambient pressure after removal of the catheter, was 0.2 +/- 0.5 mm Hg. The results indicate that this miniature strain-gauge transducer is highly accurate and stable and that it is a reliable alternative to a ventriculostomy for monitoring the ICP.