Surgical management of unruptured intracranial aneurysms

The surgical management of patients with unruptured intracranial aneurysms continues to be controversial. The criteria for withholding treatment or choosing between endovascular embolization and conventional microsurgery are not well delineated. The present study analyzes the morbidity and mortality that can be expected with modern surgical management of unruptured aneurysms, and therefore serves as a point of reference for clinical decision-making in this group of patients. A total of 202 consecutive operations for attempted clipping of unruptured intracranial aneurysms are reported. Subarachnoid hemorrhage from another aneurysm was the most common presentation (55 cases). Thirty-seven patients presented with headache, 36 with mass effect from the aneurysm, and 19 with embolic events; 11 aneurysms were associated with an arteriovenous malformation, 10 caused seizures, and 34 were incidental findings. Excellent or good outcome was achieved in 100% of patients with aneurysms less than 10 mm in diameter, 95% with aneurysms 11 to 25 mm, and 79% with aneurysms greater than 25 mm. Except for giant basilar aneurysms, size (and not location) of the aneurysm was the key predictor of risk for surgical morbidity. These data may be useful when discussing with patients the risk:benefit ratio of choosing between conservative management, endovascular embolization, and microsurgical clipping.

Transcranial Doppler detection of anterior cerebral artery vasospasm

The performance of transcranial Doppler in the detection of anterior cerebral artery vasospasm and vasospasm in patients after subarachnoid haemorrhage was analysed. Transcranial Doppler and cerebral angiography were performed within the same 24 hours on each of 41 patients with acute subarachnoid haemorrhage. Sensitivity and specificity of transcranial Doppler to classify middle cerebral arteries, anterior cerebral arteries, and patients with angiographic vasospasm were determined at mean velocities of 120 and 140 cm/s. Accuracy of transcranial Doppler was better at 140 than at 120 cm/s. For the middle cerebral artery, sensitivity was 86%, specificity 98%. For the anterior cerebral artery, sensitivity was 13%, specificity 100%. Among all patients, sensitivity was 45%, specificity 96%. Among patients with anterior communicating artery aneurysms, sensitivity was 14%, specificity 90%. Therefore, transcranial Doppler accurately differentiates between middle cerebral arteries with and without vasospasm on angiography, but has a very low sensitivity for detecting anterior cerebral artery vasospasm and vasospasm in patients with anterior communicating artery aneurysms. Since vasospasm may involve anterior cerebral arteries while sparing middle cerebral arteries, especially after rupture of an anterior communicating artery aneurysm, caution should be exercised in using negative transcranial Doppler results to make treatment decisions based on the assumed absence of vasospasm.

The clinical spectrum of unruptured intracranial aneurysms

OBJECTIVE

A retrospective study was performed to delineate the clinical characteristics of symptomatic unruptured aneurysms.

DESIGN

Patient histories, operative reports, and angiograms in 111 patients with 132 unruptured aneurysms were reviewed.

SETTING

Tertiary care university hospital.

PATIENTS

One hundred eleven patients with 132 unruptured intracranial aneurysms were studied. There were 85 women and 26 men, with a mean age of 51.2 years (age range, 11 to 77 years). Many patients were referred by community neurologists and neurosurgeons for further evaluation and neurosurgical management.

RESULTS

Fifty-four symptomatic patients were identified. Group 1 (n = 19; mean aneurysm diameter, 2.1 cm) had acute symptoms: ischemia (n = 7), headache (n = 7), seizure (n = 3), and cranial neuropathy (n = 2). Group 2 (n = 35; mean aneurysm diameter, 2.2 cm) had chronic symptoms attributed to mass effect: headache (n = 18), visual loss (n = 10), pyramidal tract dysfunction (n = 4), and facial pain (n = 3). Group 3 (n = 57; mean aneurysm diameter, 1.1 cm) had asymptomatic aneurysms.

CONCLUSIONS

Acute severe headache, comparable to subarachnoid hemorrhage headache, but without nuchal rigidity, was associated with the following mechanisms: aneurysm thrombosis, localized meningeal inflammation, and unexplained. Unruptured aneurysms may be misdiagnosed as optic neuritis or migraine, or serve as a nidus for cerebral thromboembolic events. Internal carotid artery and posterior circulation aneurysms were more likely to cause focal symptoms from mass effect than were anterior cerebral artery and middle cerebral artery aneurysms. Weeks to years may elapse before their diagnosis. The absence of subarachnoid blood does not exclude an aneurysm as a cause for acute or chronic neurologic symptoms.

Deep Hypothermic Circulatory Arrest for the Management of Complex Anterior and Posterior Circulation Aneurysms

Giant aneurysm surgery continues to be a technically difficult task with high operative morbidity. Recent advances in cardiac surgery have fueled interest in the technique of deep hypothermic circulatory arrest for the treatment of giant and complex intracranial aneurysms. Fourteen patients with giant intracranial aneurysms operated on with the technique of deep hypothermic circulatory arrest are presented. All 14 aneurysms were successfully treated. There were 2 intraoperative strokes: 1 resulted in severe disability and 1 resulted in mild disability. No significant neurological complications were related to the technique of cardiopulmonary bypass with deep hypothermic circulatory arrest. This initial experience indicates that patients with giant and complex intracranial aneurysms might benefit from a surgical approach that included the use of deep hypothermic circulatory arrest.

Deep hypothermic circulatory arrest for the management of complex anterior and posterior circulation aneurysms

Giant aneurysm surgery continues to be a technically difficult task with high operative morbidity. Recent advances in cardiac surgery have fueled interest in the technique of deep hypothermic circulatory arrest for the treatment of giant and complex intracranial aneurysms. Fourteen patients with giant intracranial aneurysms operated on with the technique of deep hypothermic circulatory arrest are presented. All 14 aneurysms were successfully treated. There were 2 intraoperative strokes: 1 resulted in severe disability and 1 resulted in mild disability. No significant neurological complications were related to the technique of cardiopulmonary bypass with deep hypothermic circulatory arrest. This initial experience indicates that patients with giant and complex intracranial aneurysms might benefit from a surgical approach that included the use of deep hypothermic circulatory arrest.

Quantitative EEG monitoring for patients with subarachnoid hemorrhage

We evaluated the sensitivity of continuous quantitative EEG in 11 patients with subarachnoid hemorrhage (SAH). We correlated compressed spectral array (CSA) and trend analysis (TA) of total power (1-30 Hz), frequency centroid (1-30 Hz), alpha ratio and percent delta power with clinical and radiological findings. For all ischemic events (n = 11), the most sensitive TA parameter was a change in total power (91%), followed by changes in alpha ratio (64%), frequency centroid (55%), and percent delta (45%). Comparable CSA features were changes in power (44%) and slowing (39%). Total power and frequency varied independently. In 4 cases, EEG findings on TA appeared before clinical changes. Continuous quantitative EEG may be useful for monitoring and predicting ischemia following SAH. TA of individual EEG parameters is more sensitive than CSA, and total power is the most sensitive.

IgM deposits at nodes of Ranvier in a patient with amyotrophic lateral sclerosis, anti-GM1 antibodies, and multifocal motor conduction block

We studied a patient with amyotrophic lateral sclerosis, multifocal motor conduction block, and IgM anti-GM1 antibodies. A sural nerve biopsy demonstrated deposits of IgM at nodes of Ranvier by direct immunofluorescence. The deposits were granular and located in the nodal gap between adjacent myelin internodes, and in some instances, they extended along the surface of the paranodal myelin sheath. When injected into rat sciatic nerve, the serum IgM bound to the nodes of Ranvier, and the binding activity was removed by preincubation with GM1. These observations suggest that anti-GM1 antibodies may have caused motor dysfunction by binding to the nodal and paranodal regions of peripheral nerve.

Early aneurysm surgery and prophylactic hypervolemic hypertensive therapy for the treatment of aneurysmal subarachnoid hemorrhage

The prevailing sentiment of North American neurosurgeons is that there is no significant difference in overall morbidity between patients who are treated with early aneurysm surgery and those who are treated with delayed aneurysm surgery. This concept is based primarily on the high incidence of ischemic events after early intervention. Recent experience, however, indicates that prophylactic hypervolemic hypertensive therapy may be beneficial in reducing delayed ischemia after early aneurysm surgery. During the preceding 21 months, we have performed 125 operations for intracranial aneurysms. Fifty-six patients in this group presented less than 7 days after subarachnoid hemorrhage (SAH) (47 within 3 days) and were treated by a prospective protocol of urgent aneurysm surgery performed within 24 hours after presentation. In all cases, the aneurysm was clipped with the use of mannitol and spinal drainage for brain relaxation. All patients were then treated with prophylactic volume expansion therapy and induced hypertension with a central venous pressure or a Swan-Ganz catheter until the 14th day after SAH. Preoperatively, 17 patients were Hunt and Hess Grade I, 9 were Grade II, 28 were Grade III, and 2 were Grade IV. In this group of 56 patients at risk for delayed ischemia from vasospasm, 5 patients had significant intraoperative complications. Ten patients (18%) had delayed cerebral ischemia, totally reversible in 6 cases, with small infarcts in 3 cases, and with 1 death (2% mortality from delayed ischemia), there were 5 cases of shunted hydrocephalus, and 3 deaths from other complications. Overall, 41 patients (73%) returned to their premorbid occupations without neurological deficit.(ABSTRACT TRUNCATED AT 250 WORDS)

Prophylactic volume expansion therapy for the prevention of delayed cerebral ischemia after early aneurysm surgery. Results of a preliminary trial

From June 1986 to June 1987, 47 consecutive patients with ruptured intracranial aneurysms were treated with immediate aneurysm surgery and prophylactic volume expansion therapy for ten to 14 days after subarachnoid hemorrhage (SAH). Twenty-four patients were admitted within three days of SAH. Twenty-three of these patients had an excellent result, and one patient died. There were no cases of delayed cerebral infarction. In 18 of 23 patients admitted more than three days after SAH, there was an excellent result. The other five patients had permanent morbidity related to the original SAH. These preliminary data suggest that immediate aneurysm surgery and aggressive postoperative prophylactic volume expansion in all patients can substantially reduce rebleeding and delayed cerebral ischemia, potential causes of morbidity, after aneurysmal subarachnoid hemorrhage. A more extensive prospective trial of this approach will be required to test this hypothesis.

Emergency management of the head-injured patient

The patient with severe head injury is a therapeutic challenge and demands all of the skills of the emergency medical specialist to manage traumatic injuries to the head, chest, abdomen, and limbs, as well as the specialized problems associated with respiratory care in a patient with raised ICP. The initial treatment is summarized in this article, which also reviews some of the most common types of head injuries and their sequelae.

Current strategies for the management of aneurysmal subarachnoid hemorrhage

Subarachnoid hemorrhage (SAH) from a ruptured intracranial aneurysm represents a major health issue. Although most people who experience an aneurysmal SAH survive to be admitted to a hospital, less than one third of these patients ever return to their premorbid status. Clearly, morbidity of this magnitude demands reevaluation of the clinical approach to this problem. This article reviews the natural history of aneurysmal SAH, and examines the current therapeutic strategies that have been suggested to improve the outcome. Careful evaluation of the existing data suggests that early aneurysm surgery and aggressive postoperative volume expansion therapy constitute the best presently available approach to patients with ruptured intracranial aneurysms.

Electromyographic findings in focal laryngeal dystonia (spastic dysphonia)

Spastic dysphonia is a clinical speech disorder characterized by spasms of the laryngeal muscles during phonation, producing a broken pattern of speech sometimes termed laryngeal stuttering. Fourteen patients with the diagnosis of spastic dysphonia based on voice quality were referred for evaluation; detailed clinical and electrophysiologic evaluations were performed. Laryngeal electromyographic (EMG) testing failed to demonstrate any spontaneous activity in the 14 patients tested. Seven patients (50%) had normal number and amplitude of motor unit potentials. Four of these had disparate amplitudes when compared with the other side, and two had complex motor unit potentials. The other seven patients (50%) had abnormal findings, including three patients with abnormally increased amplitude. Two patients had asynchronous activity characteristic of a tremor disorder. One patient had synchronous bursts of activity also affecting the diaphragm, later diagnosed as pyramidal and extrapyramidal disease. One patient had bursts of activity, and later presented with diffuse myoclonus. Laryngeal EMG therefore seemed to be a more precise way of evaluating patients presenting with a tremulous voice pattern termed spastic dysphonia. Clinical observation and EMG data demonstrated that spastic dysphonia is not a "spastic" disease. We identified patients with tremor (2), pyramidal and extrapyramidal disease (1), and myoclonic disorders (1). The remainder of the patients had clinical and EMG findings consistent with dystonia, a neurologic disorder characterized by abnormal, often action-induced, involuntary movements or uncontrolled spasms. We classify these patients as having "focal laryngeal dystonia" when the disorder occurs in isolation. It may also present as a component of a generalized dystonic syndrome.