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Monitoring brain functions is difficult in comatose patients. Continuous ICP recording is of value in cases of severe head trauma since the therapy of head-injured patients aims at preventing secondary injuries due to an elevated ICP and/or a low cerebral perfusion pressure. Insertion of an ICP device should be considered following intracranial surgery if complications are estimated as probable and, in a limited number of cases, also for evacuation of CSF, as well as for the differentiation between normal and low-pressure states. In cases of a subarachnoidal bleeding, it is recommended to insert a ventricular catheter not only as a means for ICP measurements, but also since the possibility to drain ventricular fluid might be compulsory.

In this chapter we describe a new stereotactic guiding device and the results of a preliminary study of its usefulness in predicting the location of the facial nerve during acoustic neurinoma surgery. The new device, the Neuronavigator, was developed to monitor the location of dissection during intracranial surgery. It consists of a structure with a multi-articulated arm and a 16-bit personal computer. The computer receives information about the angle of each joint in the arm and calculates the location of the tip of the arm. A computed tomography (CT) scan of the patient’s head is obtained preoperatively with three reference marks placed on the patient’s head so that the position of the head can be referenced to areas on the scan. When the Neuronavigator arm tip is placed at the operating site, the computer translates its position into coordinates on the CT scan and displays the location of the arm tip on the corresponding CT slice.

In this retrospective study we try to resolve the controversy relating to the indications for ICP monitoring after elective intracranial surgery (Johnston and Jennett 1973; Kaye and Brownbill 1981; Langfitt 1976; Nakagawa et al. 1975; Narayan et al. 1982, Takagi et al. 1986). We ask the following questions that pertain to benefits and risks of ICP monitoring: Which are the procedures and subpopulations that are most likely to be associated with raised postoperative ICP? What are the sensitivity and specificity of ICP elevations in detecting clinical deterioration? Which are the changes in patient management following ICP elevations? What is the risk of infection associated with ICP monitoring? Based on answers to these questions we attempt to formulate an optimal policy for ICP monitoring after erective surgery.

The purpose of this study is to analyze the correlation between preoperative factors and the postoperative time course of ICP following intracranial surgery of aneurysms.

The Nd-YAG laser has been introduced to intracranial surgery by Beck in 1978 (1,2). But up to now, it has not been generally accepted as a microsurgical tool (3,5). In order to get an impression of its real value in intracranial microsurgery, records of operations were reevaluated with special regard to the type of tumors, surgical steps and irradiation parameters.

The present study was intended to find out correlations between clinical manifestations and the level and course of ICP following major intracranial surgery.

It is difficult to define the point a which neuroanaesthesia evolved into a recognizable subsection of the specialty of anaesthesia. Perhaps it is better related to the development of the specialty of neurosurgery itself. There is, however, one important difference. Harvey Cushing, a pioneer in this field, was performing neurosurgical operations before World War I. In the United States at that time, however, almost all the anaesthetics were given by technicians — usually nurses — who were directly responsible to the surgeon. They were not encouraged to think for themselves, only to keep the patients immobile, to report immediately to the surgeon if anything occurred amiss, and to use whatever drugs or techniques the surgeon felt might best facilitate his operation.

A large number of patients with subarachnoid hemorrhage (SAH) develop neurologic deficits as a result of critical reductions in cerebral blood flow (CBF) and it has been suggested that CBF measurements may be useful in the clinical management of these patients. Although a number of studies have shown that flow is decreased following SAH, the relationship between CBF and clinical status is not well understood and often a poor correlation exists between these two parameters. On the other hand, factors which would tend to cause hemodynamic instability, such as arterial spasm or intracranial surgery, are frequently associated with neurologic deterioration suggesting a cause and effect relationship. In an attempt to clarify these issues, we have examined the progressive changes in CBF at various stages in the clinical course of patients with SAH and have related these changes to the corresponding alterations in neurologic status and angiographic and CT information.

In our Institute, it is our routine to monitor the post-operative Intracranial Pressure (ICP) by the subdural balloon method in the treatment of neurosurgical patients who undergo intracranial surgery.

One of the most important aims in medicine is to prevent diseases or complications of necessary interventions. As you all know, one of the major problems for each neurosurgeon is the increase of intracranial pressure, caused by brain edema, that can develop after intracranial surgery.