A retrospective clinical and pathological review of 905 consecutive brain tumor cases (excluding pituitary adenoma and recurrent tumor) was conducted to identify cases in which intratumoral hemorrhage was confirmed grossly and/or pathologically. There were 132 cases so identified, for an overall tumor hemorrhage rate of 14.6%; of these, 5.4% were classified as macroscopic and 9.2% as microscopic. The presence of hemorrhage was correlated with the neurological presentation. The highest hemorrhage rate (70.0%) was found in patients with prior neurological history who experienced apoplectic deterioration (acute-on-chronic presentation). Only 57.1% of patients with acute deterioration in the absence of prior neurological symptoms had hemorrhages. The highest hemorrhage rate for primary brain tumors was 29.2% for mixed oligodendroglioma/astrocytoma, while the highest hemorrhage rate for any tumor type was 50% for metastatic melanoma. The clinical relevance of tumor hemorrhage is discussed.
Correction of a very high grade carotid stenosis by endarterectomy in a normotensive man was followed by the development of severe unilateral head, eye, and face pain, seizures, and on the 6th day a fatal intracerebral hemorrhage. Autopsy revealed changes in the cerebral hemisphere ipsilateral to the endarterectomy that resembled the changes seen in malignant hypertension, whereas the opposite hemisphere was normal. These changes included hypercellularity and edema of arterial and arteriolar walls, with necrosis, extravasation of erythrocytes, and exudation of fibrin. We propose that the clinical and pathological features in this case were due to relative hyperperfusion of a cerebral hemisphere in which autoregulation had been impaired because of preoperative chronic hypoperfusion with chronic maximal dilatation of its blood vessels. This state of relative hyperperfusion is probably similar to the normal perfusion pressure breakthrough that occasionally occurs after the resection of cerebral arteriovenous malformations. It is similar to the breakthrough perfusion that occurs in severely hypertensive patients and results in hypertensive encephalopathy.
The configuration interaction code CIV3 is used to calculate the A-value for the 1909 Å 2s2 1S0-2s2p 3Po1 intercombination line in C III. An extensive calculation of valence shell correlation is augmented by the inclusion of core polarization effects both explicitly through further configurations with one or both 1s orbitals replaced by correlation orbitals, and also by the use of model potentials. Our recommended value of 104 ± 4s−1 for the A-value lies somewhat lower than the experimentally determined value of 121 ± 7s−1. We have estimated the expected error in our work by considering the extent of the convergence of our calculation. We also calculated the resonance transition and obtain an oscillator strength in excellent agreement with experiment.
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