Cerebral vasospasm implies narrowing of blood vessels resulting in decreased cerebral blood flow to distal tissues resulting in ischemia. It has been variously defined in the literature by different authors: 1. Clinical vasospasm defined as neurological deterioration deemed secondary to…
Definition Rupture of the intracranial aneurysm or an arteriovenous malformation during surgical clipping or coil embolization is one of the most devastating complications in neurosurgery. It is defined as a fresh or new leak in the existing vascular pathology occurring…
Definition Spinal shock occurs following an acute spinal cord injury and involves a reversible loss of all neurological function, including reflexes and rectal tone, below a particular level. It is defined as a state of transient physiologic (rather than anatomic)…
Postoperative paraplegia refers to new onset neurological deficit which occurs as a result of damage/insult to the spinal cord below T1 whereas quadriplegia/tetraplegia with or without respiratory dysfunction will occur when the insult is above the first thoracic vertebra. Usually…
Definition Pneumorrhachis is the presence of air within the spinal canal (either in the intra- or extradural space). It is a rare phenomenon and is often asymptomatic. This condition was first reported in 1977 by Gordon et al. who used the…
Definition Autonomic disturbances are disorders that affect the autonomic neurons of either or both the sympathetic and the parasympathetic nervous systems. Since the autonomic nervous system supplies almost every organ in the body, autonomic diseases influence localized organ function as…
Edema refers to abnormal, excessive accumulation of fluid in the cells, tissues, or body cavities. Brain edema results from excess accumulation of water in the extracellular and/or intracellular compartments of the brain. The brain is protected by a closed, rigid…
Definition Seizure activities are not only difficult to diagnose intraoperative in an anesthetized patient; they are also less recognized clinically, as compared to postoperative seizures in the intensive care unit. Seizure activity may be evident only in cases of incomplete…
Definition Pneumocephalus is defined as an asymptomatic intracranial collection of air, commonly occurring after craniotomy or cranial burr hole. In a retrospective study, the incidence of intracranial air collection varied from 73% in park-bench position, 57% in prone position, and…
Definition Normal perfusion pressure breakthrough (NPPB) can be defined as the occurrence of multifocal areas of hemorrhage associated with unexplained cerebral edema after the resection of high-flow arteriovenous malformations (AVMs). Various theories have been proposed to explain the hemodynamic basis…