Neurosurgery
-
The authors report their experience with 25 patients (mean age, 44.3 +/- 12.1 years) with an intracerebral hematoma (ICH) from a ruptured aneurysm who were emergently operated on without angiography. Instead, preoperative high-resolution infusion computed tomography (CT) scans were used to identify the aneurysm causing the hemorrhage. In all patients, the preoperative Glasgow Coma Scale score was < 5 and brain stem compression was evident. ⋯ Twelve patients survived, eight of whom were only moderately disabled and were independent at 6-months' follow-up. Of the 13 patients who died, all except one died within 4 days of admission. The authors conclude that although angiographic verification before aneurysm surgery is preferable, in the moribund patient with intracerebral hemorrhage, infusion CT scanning provides sufficient information concerning vascular anatomy to allow rational emergency craniotomy and aneurysm clipping.
-
The pathophysiological mechanisms to explain peritumoral edema have not been clarified. Multiple aspects of brain edema secondary to supratentorial meningiomas were prospectively investigated in a group of 29 patients who underwent surgery consecutively. Sixty-nine tumor samples were analyzed for prostanoid levels. ⋯ Otherwise, histology, pathological features of tumor aggressiveness, or mechanical parameters, such as its volume, location, and insertion site, did not correlate well with edema parameters or with prostaglandin levels. Similarly, tumor water content, imaging parameters in computed tomography and magnetic resonance, and operative findings (including dissection plane, vascularity, and tumor firmness) did not correlate well with edema parameters. Although a direct cause-effect relationship between prostaglandins and peritumoral edema is not conclusively established, the circumstantial evidence of the ability of prostaglandins to induce vasogenic brain edema and the robust association with peritumoral edema is persuasive.(ABSTRACT TRUNCATED AT 250 WORDS)
-
The clinical relevance of any scheme for classification of vascular malformations of the brain remains controversial. Widely accepted pathologic classifications include discrete venous, arteriovenous, capillary, and cavernous malformations. Of 280 cases of possible vascular malformations evaluated by a single cerebrovascular service during a 5-year period, 14 were instances of mixed vascular malformations including definite features of more than one pathologically discrete type of malformation within the same lesion. ⋯ In the other three cases, manifestations of clinical lesions were due to arteriovenous shunting within a venous malformation. We conclude that mixed vascular malformations of the brain are rare entities with distinct clinical, radiological, and pathological profiles. Their identification generates several hypotheses about common pathogenesis or causation-evolution among different types of lesions.
-
A rare case of hydatid disease of the lumbar extradural area and of the paravertebral muscles is reported. The patient underwent surgery, resulting in complete recovery. The limitations of computed tomography and the benefits of magnetic resonance imaging in forming a diagnosis are discussed. Magnetic resonance has been found to be an invaluable tool, not only in detecting the soft tissue extent of the disease but also in delineating the viability of hydatid cysts.
-
A technique for achieving a combined pterional (subfrontal) and anterior temporal exposure for aneurysms of the upper basilar complex is described. The technique is not new, but it does involve several modifications not previously described. A standard pterional skin incision that extends below the zygoma just anterior to the tragus is used. ⋯ After opening the dura on a flap centered on the sylvian fissure, the medial cisterns are opened widely and the fissure is opened all the way to the middle cerebral bifurcation. Posterolateral temporal retraction and, when necessary, subpial resection of the anteromedial portion of the uncus enhance the exposure posterolateral to the oculomotor nerve. The advantages of this combined approach are as follows: it combines the more anterior angle of vision offered by the pterional approach with the lateral line of vision offered by the subtemporal approach; it eliminates the need for temporal lobe elevation and it allows simultaneous clipping of other aneurysms of the ipsilateral anterior circle of Willis; and it also reduces the frequency and severity of oculomotor palsy, when compared with the subtemporal approach.