Definition Syndrome of inappropriate antidiuretic hormone secretion (SIADH) is caused by excessive or inappropriate secretion or action of antidiuretic hormone (ADH), resulting in: Dilutional hyponatremia without clinically apparent hypervolemia (also known as euvolemic) Reduced plasma osmolality Impaired water excretion with…
Definition Diabetes insipidus (DI) is a heterogeneous condition characterized by polyuria and polydipsia caused either due to a lack of secretion of vasopressin (antidiuretic hormone) from posterior pituitary, its physiological suppression following excessive water intake, kidney resistance to its action,…
Definition Cerebral salt wasting (CSW) is a condition characterized by renal loss of sodium leading to hyponatremia and concomitant decrease in extracellular fluid volume due to an intracranial disease. CSW was first described in 1950 by Peters et al. They reported…
Osmotic demyelination syndrome (ODS) refers to demyelination of white matter tracts traversing the pons (central pontine myelinolysis (CPM)) or in the extrapontine regions (extrapontine myelinolysis (EPM)). CPM is a noninflammatory, symmetric, demyelinating condition involving the central pons. EPM refers 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 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…
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…