Idiopathic Intracranial Hypertension: Review of Clinical Syndrome, Imaging Findings, and Treatment.

Idiopathic intracranial hypertension (IIH) is a syndrome of unknown cause that is increasing in frequency. Patients who are typically women of childbearing age and obese present with headaches and may also present with visual changes that may become chronic. The purpose of this review is to describe the possible mechanisms for this disease and also to illustrate the ever increasing role of imaging in the diagnosis of this disorder. In addition, the various methods of treatment including medical and surgical will be reviewed. The fact that idiopathic intracranial hypertension has undergone many name changes over the years serves as a reminder that the underlying mechanism is still not well understood. Although there are only several possible mechanisms that can cause increased intracranial pressure, it is still not certain which of these mechanisms is involved. The role of imaging has significantly changed in the evaluation of patients with possible IIH. First, it is involved in ruling out secondary causes of increased intracranial pressure. In addition, there is now ample evidence that the previously held belief that imaging of patients with IIH should be normal is incorrect but rather that there are several subtle findings that radiologists need to look for. These findings include a partially empty sella, flattening of the posterior globe, cupping of optic disks and distension of the optic nerve sheaths. In addition, the role of intracranial venography is playing an ever increasing role due to the finding that a very high percentage of patients have dural venous sinus stenoses. It is becoming clear that there is potentially true morbidity associated with idiopathic intracranial hypertension. The earlier the disease can be diagnosed, the earlier treatment can be started to minimalize permanent visual changes including blindness. Treatment varies from institution to institution due to the fact that multiple specialists with different perspectives treat these patients. Knowledge of subtle imaging features associated with idiopathic intracranial hypertension can help radiologists establish the diagnosis earlier and potentially prevent complications of this disorder. However imaging has not as of yet been shown to be beneficial in managing patients with idiopathic intracranial hypertension.

Acute management of acquired brain injury part I: an evidence-based review of non-pharmacological interventions.

PRIMARY OBJECTIVE: To review the literature on non-pharmacological interventions used in acute settings to manage elevated intracranial pressure (ICP) and minimize cerebral damage in patients with acquired brain injury (ABI). MAIN OUTCOMES: A literature search of multiple databases (CINAHL, EMBASE, MEDLINE and PSYCHINFO) and hand-searched articles covering the years 1980-2008 was performed. Peer reviewed articles were assessed for methodological quality using the PEDro scoring system for randomized controlled trials (RCTs) and the Downs and Black tool for RCTs and non-randomized trials. Levels of evidence were assigned and recommendations made. RESULTS: Five non-invasive interventions for acute ABI management were assessed: adjusting head posture, body rotation (continuous rotational therapy and prone positioning), hyperventilation, hypothermia and hyperbaric oxygen. Two invasive interventions were also reviewed: cerebrospinal fluid (CSF) drainage and decompressive craniectomy (DC). CONCLUSIONS: There is a paucity of information regarding non-pharmacological acute management of patients with ABI. Strong levels of evidence were found for only four of the seven interventions (decompressive craniectomy, cerebrospinal fluid drainage, hypothermia and hyperbaric oxygen) and only for specific components of their use. Further research into all interventions is warranted.

Decompressive craniectomy for intracerebral hemorrhage.

OBJECTIVE: Intracerebral hemorrhage (ICH) has a high mortality rate and leaves most survivors disabled. The dismal outcome is mostly due to the mass effect of hematoma plus edema. Major clinical trials show no benefit from surgical or medical treatment. Decompressive craniectomy has, however, proven beneficial for large ischemic brain infarction with massive swelling. We hypothesized that craniectomy can improve ICH outcome as well. METHODS: We used the model of autologous blood injection into the basal ganglia in rats. After induction of ICH and then magnetic resonance imaging, animals were randomly allocated to groups representing no craniectomy (n = 10) or to craniectomy at 1, 6, or 24 hours. A fifth group without ICH underwent craniectomy only. Neurological and behavioral outcomes were assessed on days 1, 3, and 7 after ICH induction. Furthermore, terminal deoxynucleotidyl transferase dUTP nick-end labeling-positive cells were counted. RESULTS: After 7 days, compared with the ICH + no craniectomy group, all craniectomy groups had strikingly lower mortality (P < 0.01), much better neurological outcome (P < 0.001), and more favorable behavioral outcome. A trend occurred in the ICH + no craniectomy group toward more robust apoptosis. CONCLUSION: Decompressive craniectomy performed up to 24 hours improved outcome after experimental ICH, with earlier intervention of greater benefit.

Sir Victor Horsley's contributions to the study and treatment of gunshot wounds of the head.

Sir Victor Horsley'S many contributions to neurological surgery include experimental and clinical studies of gunshot wounds (GSW) of the head. Horsley's publications from 1894 to 1897 and 1914 to 1915 on GSWs were reviewed. Horsley described GSWs in animal and clay models, illustrating characteristics of the primary missile tract and secondary cavitation. A transcranial GSW model in 67 dogs related intracranial damage to the projectile's velocity and sectional area, producing a marked sudden increase in intracranial pressure that presumably "tunneled" to the medullary respiratory and cardiac centers. If the resultant sudden apnea was treated with artificial respiration and prompt surgical decompression, the animal often survived. In these animal experiments, Horsley clearly described increased intracranial pressure, hypertension, and bradycardia-later recognized as the Cushing response or triad. With the onset of World War I, Horsley again reviewed the ballistics of military weaponry, emphasizing projectile spin and velocity as the main wounding mechanisms. He was outspoken against the "wicked tradition" of neglecting cranial GSWs and personally treated cases with aggressive respiratory support and prompt decompression of devitalized tissue. Horsley's contributions to the experimental and clinical aspects of GSWs to the head are consistent with his other important contributions to neurosurgery and have largely stood the test of time.

Craniectomía descompresiva en niños con traumatismo encefalocraneano grave, una alternativa terapéutica en la hipertensión endocraneana refractaria: presentación de dos casos clínicos / Decompressive craniectomy in children with severe encephalocranial trauma, an alternative treatment in the management of refractory intracranial hypertension: 2 clinical cases

Introducción: La craniectromía descompresiva continúa siendo una terapia controvertida por sus criterios de indicación y por su real eficacia en niños que cursan con edema cerebral difuso post-traumático que desarrollan hipertensión endocraneana grave y refractaria a la terapia convencional empleada en las Unidades de Cuidados Intensivos Pediátricos. La morbimortalidad asociada a la hipertensión endocraneana es elevada, a pesar de los avances en su diagnóstico, neuromonitoreo y manejo médico. Objetivo: comunicar los resultados de esta técnica neuroquirúrgica, en pacientes con diagnóstico de TEC grave e hipertensión endocraneana refractaria a la terapia médica convencional, en la Unidad de Cuidados Intensivos del Hospital Dr. Sótero del Río. Se planteó la craniectomía descompresiva en aquellos pacientes con diagnóstico de TEC grave, Glasgow de ingreso entre 4 y 8, TAC cerebral que descartara la presencia de lesiones con efecto de masa y alzas de la PIC en cifras superiores a 40 mmHg y PPC por sobre 60 mmHg. Casos clínicos: dos pacientes de 2 meses y 8 años, con diagnóstico de TEC grave, Glasgow de ingreso 5 e HTEC refractaria, fueron sometidos a craniectomía descompresiva bifrontal. Ambos sobrevivieron, uno con secuelas graves permanentes y el otro con secuelas leves, logrando una adecuada rehabilitación social. Conclusión: el monitoreo de la presión intracraneana (PIC), en conjunto con el estudio de imágenes, como parte integral de la evaluación neurointensiva, identificará a aquellos pacientes en riesgo de edema cerebral incontrolable, en quienes la craniectomía descompresiva debiera ser considerada como una alternativa útil de tratamiento para prevenir el daño isquémico cerebral irreversible secundario a este