RESUMEN
OBJECTIVE AND IMPORTANCE: A case of chordoid meningioma originating in the right sylvian fissure is reported. Chordoid meningiomas are uncommon tumors. This is the first reported case of a chordoid meningioma without dural attachment arising in the sylvian fissure. CLINICAL PRESENTATION: The patient presented with a generalized seizure. A heterogeneously enhancing right frontotemporal mass was identified on magnetic resonance imaging of the brain. INTERVENTION: The patient underwent a failed stereotactic biopsy attempt elsewhere. The tumor was ultimately resected using standard microsurgical techniques. CONCLUSION: Meningiomas originate from arachnoid cap cells and can arise at locations remote from the pachymeninges. Although rare, meningiomas should be included on the differential diagnosis of sylvian fissure lesions.
Asunto(s)
Neoplasias del Plexo Coroideo/cirugía , Neoplasias Meníngeas/cirugía , Adulto , Neoplasias del Plexo Coroideo/patología , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Neoplasias Meníngeas/patología , Meningioma , Neurocirugia/métodosRESUMEN
OBJECTIVE: Survival of cardiac arrest (CA) after aneurysmal subarachnoid hemorrhage (SAH) is poorly characterized. We analyzed the clinical course and outcome of patients who survived resuscitation for CA after aneurysmal SAH. METHODS: Medical records of all patients with acute SAH treated at Mayo Clinic between 1990 and 1997 were reviewed. Three hundred five consecutive patients with angiographically proven aneurysmal SAH presenting within 7 days of ictus were analyzed. CA was defined as a pulseless state, documented by medical personnel, for which resuscitation was performed. Outcome was measured with the Glasgow Outcome Scale score at longest follow-up (mean, 16 mo). RESULTS: Data from 11 patients (3.6%) who had 14 episodes of CA were analyzed. Six patients had CA before reaching the hospital and were successfully resuscitated. Nine of 14 CA episodes occurred at hemorrhage or rehemorrhage. No patient with in-hospital CA failed to be resuscitated. Overall mortality in patients who had CA (46%) was higher than that of patients without CA (15%; P = 0.019). Outcome for all patients who had CA (mean Glasgow Outcome Scale score, 2.5) was worse than for patients without CA (mean Glasgow Outcome Scale score, 3.9; P = 0.005). However, half of the survivors of CA after SAH were living independently with limited deficit at longest follow-up. CONCLUSION: Most cases of CA occur at the time of initial or recurrent SAH. Resuscitation for in-hospital CA is likely to be successful. Although CA after aneurysmal SAH is associated with significantly higher mortality, the outcome of survivors of CA is not worse than that for other patients after aneurysmal SAH.
Asunto(s)
Paro Cardíaco/etiología , Paro Cardíaco/mortalidad , Hemorragia Subaracnoidea/complicaciones , Sobrevida , Adulto , Angioplastia de Balón , Femenino , Estudios de Seguimiento , Escala de Consecuencias de Glasgow/estadística & datos numéricos , Humanos , Masculino , Registros Médicos/estadística & datos numéricos , Persona de Mediana Edad , Estudios Retrospectivos , Hemorragia Subaracnoidea/terapia , Resultado del TratamientoRESUMEN
OBJECT: Previous studies have indicated an increased incidence of death in patients with subarachnoid hemorrhage (SAH) who are currently receiving anticoagulation therapy. The significance of previous aspirin use in patients with SAH is unknown. The authors analyzed the effects of prior aspirin use on clinical course and outcomes following aneurysmal SAH. METHODS: The medical records of 305 patients with angiogram-confirmed aneurysmal SAH who consecutively presented to our institution between 1990 and 1997 within 7 days of ictus were analyzed. Twenty-nine (9.5%) of these patients had a history of regular aspirin use before onset of the SAH. The Glasgow Outcome Scale (GOS) was used to measure patient outcome at the longest available follow up. Aspirin users were older on average than nonusers (59 years of age compared with 53 years; p = 0.018). The mean admission Hunt and Hess grades of patients with and without aspirin use were similar (2 compared with 2.3; p = 0.51). Two trends, which did not reach statistical significance, were observed. 1) The rebleeding rate in aspirin users was 14.3%, compared with a 4.7% rebleeding rate in nonusers (p = 0.06). 2) Permanent disability from vasospasm was less common among aspirin users (23% compared with 50%; p = 0.069). Outcomes did not differ between aspirin users and nonusers (mean GOS Score 3.83 compared with GOS Score 3.86, respectively; p = 0.82). CONCLUSIONS: Despite trends indicating increased rebleeding rates and a lower incidence of permanent disability due to delayed ischemic neurological deficits, there was no significant effect of previous aspirin use on overall outcome following aneurysmal SAH. Based on these preliminary data, the presence of an intracranial aneurysm is not a strict contraindication to aspirin use.
Asunto(s)
Aspirina/efectos adversos , Inhibidores de Agregación Plaquetaria/efectos adversos , Hemorragia Subaracnoidea/tratamiento farmacológico , Vasoespasmo Intracraneal/tratamiento farmacológico , Adulto , Anciano , Aspirina/administración & dosificación , Femenino , Humanos , Incidencia , Masculino , Registros Médicos , Persona de Mediana Edad , Inhibidores de Agregación Plaquetaria/administración & dosificación , Recurrencia , Factores de Riesgo , Hemorragia Subaracnoidea/epidemiología , Resultado del Tratamiento , Vasoespasmo Intracraneal/epidemiologíaRESUMEN
Radiation-induced neoplasms are extremely rare after stereotactic radiosurgery. To date, only 3 cases meet Cahan's criteria in the world literature. We present a fourth case of a radiation-induced neoplasm arising after radiosurgery. The patient is a 43-year-old woman who presented with a right cerebellar anaplastic astrocytoma 64 months after radiosurgery for metastatic melanoma. Initially, 3 brain metastases involving the inferior right temporal (2 tumors) and right frontal regions were treated. Following radiosurgery, the patient underwent whole brain radiotherapy (37.5 Gy). Twenty-two months later, a second radiosurgical procedure was performed for a recurrent right temporal lobe metastasis. The area of cerebellum where the glioma developed received a maximum dose of 7.7 and 1.5 Gy during the 2 procedures, respectively. Support that radiosurgery contributed to the development of this glioma are the tumor's location and the rarity of adult cerebellar astrocytomas. The risk of radiation-induced tumors after radiosurgery is unknown. To better define the incidence of radiation-induced neoplasms after radiosurgery, all potential cases should be presented and discussed in an open, candid fashion.
Asunto(s)
Astrocitoma/etiología , Neoplasias Cerebelosas/etiología , Irradiación Craneana/efectos adversos , Neoplasias Inducidas por Radiación/etiología , Radiocirugia/efectos adversos , Adulto , Astrocitoma/patología , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundario , Neoplasias Cerebelosas/patología , Terapia Combinada , Femenino , Humanos , Imagen por Resonancia Magnética , Melanoma/radioterapia , Melanoma/secundario , Recurrencia Local de Neoplasia/radioterapia , Neoplasias Inducidas por Radiación/patología , Dosis de Radiación , Resultado del TratamientoRESUMEN
INTRODUCTION: Recent evidence suggests that magnesium may be neuroprotective in the setting of cerebral ischemia, and therapeutic magnesium infusion has been proposed for prophylaxis and treatment of delayed ischemic neurological deficit (DIND) resulting from vasospasm in patients with aneurysmal subarachnoid hemorrhage (SAH). We studied the association between serum magnesium levels, the development of DIND, and the outcomes of patients with SAH. METHODS: We studied 128 consecutive patients with aneurysmal SAH treated at our institution between 1990 and 1997 who had a serum magnesium level measured at least once during the acute phase of their hospitalization. Delayed ischemic neurological deficit was defined as severe (major focal deficit or coma), moderate (incomplete focal deficit or decreased sensorium without coma), or none. RESULTS: There was no significant difference in mean, minimum, or maximum serum magnesium levels between patients with and without DIND (1.93, 1.83, 2.02 versus 1.91, 1.84, 1.97 mg/dL, respectively). Similarly, no difference was found in mean serum magnesium levels among patients with severe (1.94 mg/dL), moderate (1.92 mg/dL), or no DIND (1.91 mg/dL). Analyses of serum magnesium levels before (0-4 days following SAH), during (4-14 days following SAH), and after (greater than 14 days following SAH) the period of highest risk for vasospasm revealed no association with the development or severity of DIND. Permanent deficit or death resulting from vasospasm and Glasgow Outcome Scale score at longest follow-up were similarly unaffected by serum magnesium levels overall or during any time interval. Forty (31.5%) patients were hypomagnesemic (less than 1.7 mg/dL) during hospitalization, but no difference in outcome (p = 0.185) or development of DIND (p = 0.785) was found when compared to patients with normal (1.7-2.1 mg/dL) or high (greater than 2.1 mg/dL) magnesium serum levels. CONCLUSION: We identified no relationship between serum magnesium levels and the development of DIND or outcome following aneurysmal SAH. Based on these data, magnesium supplementation to normal or high-normal physiological ranges seems unlikely to be beneficial for DIND resulting from vasospasm. However, no inference can be made regarding the value of therapeutic infusion of magnesium to supraphysiological levels.
Asunto(s)
Aneurisma Intracraneal/complicaciones , Magnesio/sangre , Hemorragia Subaracnoidea/sangre , Hemorragia Subaracnoidea/complicaciones , Vasoespasmo Intracraneal/sangre , Vasoespasmo Intracraneal/etiología , Adulto , Anciano , Encéfalo/irrigación sanguínea , Isquemia Encefálica/sangre , Isquemia Encefálica/complicaciones , Circulación Cerebrovascular/fisiología , Femenino , Escala de Coma de Glasgow , Humanos , Masculino , Persona de Mediana Edad , Hemorragia Subaracnoidea/diagnósticoRESUMEN
OBJECTIVE: We report an unusual case of an extraventricular choroid plexus papilloma (CPP) occupying the right ventral foramen magnum and lower right cerebellopontine angle (CPA), occurring together with a petro-tentorial meningioma. The clinical presentation, preoperative imaging, differential diagnosis, surgical treatment and histologic features of the two tumors are discussed. CASE DESCRIPTION: The patient presented with a 2-month history of headache, altered facial sensation, dysphagia, and gait unsteadiness. Neurologic examination confirmed a wide-based, unsteady gait, hoarse voice, anisocoria, and partial right vocal cord paralysis. Diagnostic imaging demonstrated right petro-tentorial and right ventral foramen magnum lesions, both hyperintense on contrasted images and suggestive of meningiomas. A right suboccipital craniotomy and far lateral approach was used to resect both tumors. The petro-tentorial tumor was a histologically confirmed meningioma, but the ventral foramen magnum tumor was an extraventricular CPP. CONCLUSIONS: This is a rare occurrence of concomitant meningioma and CPP. There is no known link between these two tumors. An exophytic 4th ventricular CPP must be considered in the differential diagnosis of a CPA or foramen magnum tumor.
Asunto(s)
Neoplasias del Plexo Coroideo , Glioma , Neoplasias Infratentoriales , Neoplasias Meníngeas , Meningioma , Neoplasias Primarias Múltiples , Neoplasias del Plexo Coroideo/diagnóstico , Neoplasias del Plexo Coroideo/cirugía , Femenino , Foramen Magno , Glioma/diagnóstico , Glioma/cirugía , Humanos , Neoplasias Infratentoriales/diagnóstico , Neoplasias Infratentoriales/cirugía , Imagen por Resonancia Magnética/métodos , Neoplasias Meníngeas/diagnóstico , Neoplasias Meníngeas/cirugía , Meningioma/diagnóstico , Meningioma/cirugía , Persona de Mediana Edad , Neoplasias Primarias Múltiples/diagnóstico , Neoplasias Primarias Múltiples/cirugíaRESUMEN
OBJECTIVE: Pulmonary complications challenge the medical management of patients who have sustained aneurysmal subarachnoid hemorrhage (SAH). We assessed the frequency and types of pulmonary complications after aneurysmal SAH and analyzed the impact of pulmonary complications on patient outcome. METHODS: We reviewed the records of all patients with acute SAH treated at our institution between 1990 and 1997. Three hundred five consecutive patients with an aneurysmal hemorrhage source documented by angiography and treated within 7 days of ictus were analyzed. Outcomes at longest follow-up (mean, 16 mo) were measured by use of the Glasgow Outcome Scale. RESULTS: Pulmonary complications were documented in 66 patients (22%). The pulmonary complications were nosocomial pneumonia in 26 patients (9%), congestive heart failure in 23 (8%), aspiration pneumonia in 17 (6%), neurogenic pulmonary edema in 5 (2%), pulmonary embolus in 2 (<1%), and other pulmonary disorders in 4 (1%); 11 patients had two pulmonary complications. The incidence of symptomatic vasospasm was greater in patients with pulmonary complications (63%) than in patients without pulmonary complications (31%) (P = 0.001), and this association was independent of age and clinical grade at admission (odds ratio, 3.68; P < 0.001). Overall clinical outcomes were worse in patients with pulmonary complications (mean Glasgow Outcome Scale score, 3.3) than in patients without pulmonary complications (mean Glasgow Outcome Scale score, 4.0; P = 0.0001), but pulmonary complications were not an independent predictor of worse outcome when adjusted for age and clinical grade at admission (odds ratio, 1.38; P = 0.315). CONCLUSION: Patients who experience pulmonary complications after aneurysmal SAH have a higher incidence of symptomatic vasospasm than do patients without pulmonary complications. This most likely reflects both the failure to maintain aggressive hypervolemic and hyperdynamic therapy in patients with pulmonary compromise and the possible precipitation of congestive heart failure by hypervolemic therapy in patients with preexisting delayed ischemic neurological deficit. Although patients with pulmonary complications have worse overall clinical outcomes than do patients without pulmonary complications, this is attributable to older age and worse clinical grades at admission.
Asunto(s)
Enfermedades Pulmonares/etiología , Hemorragia Subaracnoidea/complicaciones , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Angiografía Cerebral , Femenino , Estudios de Seguimiento , Escala de Consecuencias de Glasgow , Humanos , Enfermedades Pulmonares/diagnóstico por imagen , Enfermedades Pulmonares/terapia , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Hemorragia Subaracnoidea/diagnóstico por imagen , Hemorragia Subaracnoidea/terapia , Factores de TiempoRESUMEN
BACKGROUND AND PURPOSE: We retrospectively analyzed our results with Guglielmi detachable coils (GDCs) for the endovascular occlusion of acutely ruptured saccular cerebral aneurysms over 10 years. METHODS: Between 1991-2000, 83 patients (mean age, 56.1 years) with aneurysmal subarachnoid hemorrhage were treated with endovascular GDCs. Patients with aneurysms due to trauma or dissection and those with mycotic or fusiform aneurysms were excluded. Mean follow-up in survivors was 19.1 months, and the mean Hunt-Hess grade at admission was 2.2. Angiographic follow-up was performed in 93% of surviving patients (mean interval, 11.6 months). The basilar caput (34 patients) and anterior communicating artery complex (19 patients) were most commonly treated. RESULTS: Sixty-four patients (77%) had a Glasgow Outcome Scale score (GOS) of 4 or 5, nine (11%) had a score of 2 or 3, and 10 (12%) died. At follow-up, 24 patients (35%) had complete aneurysm occlusion, 18 (26%) had a dog-ear remnant, 24 (35%) had a residual neck, and two (3%) had residual aneurysm filling. No treated aneurysm rebled. Three patients required surgical repair after incomplete endovascular treatment. Two or more GDC occlusion procedures were required in 28 patients (34%). Major procedural complications occurred in two patients (2%), resulting in serious neurologic disability or death. CONCLUSION: Endovascular treatment of ruptured cerebral aneurysms with GDCs has low morbidity, and it facilitates good overall outcomes in patients after subarachnoid hemorrhage. The short-term effectiveness of GDC occlusion in preventing aneurysmal rebleeding was excellent. Durability of the treatment in preventing long-term rebleeding as compared with direct surgical clipping warrants further study. Advances in device technology and technique may improve future outcomes.
Asunto(s)
Aneurisma Roto/terapia , Embolización Terapéutica , Aneurisma Intracraneal/terapia , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Aneurisma Roto/diagnóstico por imagen , Aneurisma Roto/mortalidad , Daño Encefálico Crónico/diagnóstico por imagen , Daño Encefálico Crónico/mortalidad , Causas de Muerte , Angiografía Cerebral , Evaluación de la Discapacidad , Femenino , Estudios de Seguimiento , Escala de Consecuencias de Glasgow , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Hemorragia Subaracnoidea/diagnóstico por imagen , Hemorragia Subaracnoidea/mortalidad , Hemorragia Subaracnoidea/terapia , Tasa de SupervivenciaRESUMEN
OBJECT: The authors studied patients with aneurysmal subarachnoid hemorrhage (SAH) to determine whether the incidence of symptomatic vasospasm or overall clinical outcomes differed between patients treated with craniotomy and clip application and those treated by endovascular coil occlusion. METHODS: The authors reviewed 415 consecutive patients with aneurysmal SAH who had been treated with either craniotomy and clip application or endovascular coil occlusion at a single institution between 1990 and 2000. Three hundred thirty-nine patients underwent surgical clip application procedures, whereas 76 patients underwent endovascular coil occlusion. Symptomatic vasospasm occurred in 39% of patients treated with clip application, 30% of patients treated with endovascular coil occlusion, and 37% of patients overall. Compared with patients treated with clip application, patients treated with endovascular coil occlusion were more likely to suffer acute hydrocephalus (50 compared with 34%, p = 0.008) and were more likely to harbor aneurysms in the posterior circulation (53 compared with 20%, p < 0.001). Logistic regression models controlling for patient age, admission World Federation of Neurosurgical Societies (WFNS) grade, acute hydrocephalus, aneurysm location, and day of treatment revealed that, among patients with an admission WFNS grade of I to III, endovascular coil occlusion carried a lower risk of symptomatic vasospasm (odds ratio [OR] 0.34, 95% confidence interval [CI] 0.14-0.8) and death or permanent neurological deficit due to vasospasm (OR 0.28, 95% CI 0.08-1) compared with craniotomy and clip application. Similar models revealed no difference in the likelihood of a Glasgow Outcome Scale score of 3 or less at the longest follow-up review (median 6 months) between treatment groups (OR 0.58, 95% CI 0.28-1.21). CONCLUSIONS: Patients with better clinical grades (WFNS Grades I-III) at hospital admission were less likely to suffer symptomatic vasospasm when treated by endovascular coil occlusion, compared with craniotomy and clip application. Nevertheless, there was no significant difference in overall outcome at the longest follow-up examination between the two treatment groups.
Asunto(s)
Craneotomía , Embolización Terapéutica , Evaluación de Resultado en la Atención de Salud , Hemorragia Subaracnoidea/complicaciones , Hemorragia Subaracnoidea/cirugía , Vasoespasmo Intracraneal/etiología , Vasoespasmo Intracraneal/prevención & control , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Escala de Coma de Glasgow , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de TiempoRESUMEN
OBJECTIVE AND IMPORTANCE: Cyst formation within the brain parenchyma after endovascular coil occlusion of an intracranial aneurysm is a previously undescribed occurrence. We describe a 70-year-old woman who presented with a symptomatic pontine cyst 1 year after uncomplicated stenting and Guglielmi detachable coil occlusion of an unruptured basilar artery trunk aneurysm. CLINICAL PRESENTATION: A 70-year-old woman presented with an episode of transient dysequilibrium and gait difficulty. Magnetic resonance imaging and cerebral angiography demonstrated a 15-mm distal basilar artery trunk aneurysm. Endovascular stenting and coil occlusion of the aneurysm were performed without technical complications. One year after the initial treatment, the patient developed progressive dysarthria, dysphagia, diplopia, and left hemiparesis. A large pontomesencephalic cyst adjacent to the coiled basilar aneurysm was identified on magnetic resonance imaging scans. INTERVENTION: A subtemporal craniotomy and decompression of the pontomesencephalic cyst were performed. The patient's symptoms of brainstem dysfunction improved temporarily but recurred within 2 months, necessitating reoperation for cyst drainage and placement of a cyst-peritoneal shunt. CONCLUSION: Intra-axial cyst formation after stenting and endovascular occlusion of an intracranial aneurysm is an unusual occurrence and should be considered in the differential diagnosis of new neurological deficits after endovascular treatment. The pathophysiological mechanism of cyst formation in this case is not known.
Asunto(s)
Oclusión con Balón/efectos adversos , Implantación de Prótesis Vascular/efectos adversos , Encefalopatías/diagnóstico por imagen , Encefalopatías/etiología , Tronco Encefálico/diagnóstico por imagen , Tronco Encefálico/patología , Quistes/diagnóstico por imagen , Quistes/etiología , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/terapia , Anciano , Encefalopatías/patología , Angiografía Cerebral , Quistes/patología , Femenino , Humanos , Aneurisma Intracraneal/patología , Imagen por Resonancia MagnéticaRESUMEN
OBJECT: Despite the widespread use of ventriculostomy in the treatment of acute hydrocephalus after aneurysmal subarachnoid hemorrhage (SAH), there is no consensus regarding the risk of rebleeding associated with ventriculostomy before aneurysm repair. This present study was conducted to assess the risk of rebleeding after preoperative ventriculostomy in patients with aneurysmal SAH. METHODS: The authors reviewed the records of all patients with acute SAH who were treated at a single institution between 1990 and 1997. Thus, the records of 304 consecutive patients in whom an aneurysmal SAH source was documented on angiographic studies and who had presented to the authors' institution within 7 days of ictus were analyzed. Re-bleeding was confirmed by evidence of recurrent hemorrhage on computerized tomography scans in all cases. Forty-five patients underwent ventriculostomy for acute hydrocephalus after aneurysmal SAH at least 24 hours before aneurysm repair. Ventriculostomy was performed within 24 hours of SAH in 38 patients, within 24 to 48 hours in three patients, and more than 48 hours after SAH in four patients. The mean time interval between SAH and surgery in patients who did not undergo ventriculostomy was no different from the mean interval between ventriculostomy and surgery in patients who underwent preoperative ventriculostomy (3.6 compared with 3.8 days, p = 0.81). Fourteen (5.4%) of the 259 patients who did not undergo ventriculostomy suffered preoperative aneurysm rebleeding, whereas two (4.4%) of the 45 patients who underwent preoperative ventriculostomy had aneurysm rebleeding. CONCLUSIONS: No evidence was found that preoperative ventriculostomy performed after aneurysmal SAH is associated with an increased risk of aneurysm rebleeding when early aneurysm surgery is performed.
Asunto(s)
Hidrocefalia/etiología , Hidrocefalia/cirugía , Aneurisma Intracraneal/complicaciones , Cuidados Preoperatorios , Hemorragia Subaracnoidea/etiología , Ventriculostomía , Enfermedad Aguda , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Aneurisma Intracraneal/cirugía , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Medición de Riesgo , Prevención Secundaria , Factores de Tiempo , Ventriculostomía/efectos adversosRESUMEN
OBJECT: Predicting which patients with aneurysmal subarachnoid hemorrhage (SAH) will develop delayed ischemic neurological deficit (DIND) due to vasospasm remains subjective and unreliable. The authors analyzed the utility of a novel software-based technique to quantify hemorrhage volume in patients with Fisher Grade 3 aneurysmal SAH. METHODS: Patients with aneurysmal SAH in whom a computerized tomography (CT) scan was performed within 72 hours of ictus and demonstrated Fisher Grade 3 SAH were analyzed. Severe DIND was defined as new onset complete focal deficit or coma. Moderate DIND was defined as new onset partial focal deficit or impaired consciousness without coma. Fifteen consecutive patients with severe DIND, 13 consecutive patients with moderate DIND, and 12 consecutive patients without DIND were analyzed. Software-based volumetric quantification was performed on digitized admission CT scans by a single examiner blinded to clinical information. There was no significant difference in age, sex, admission Hunt and Hess grade, or time to admission CT scan among the three groups (none, moderate, or severe DIND). Patients with severe DIND had a significantly higher cisternal volume of hemorrhage (median 30.5 cm3) than patients with moderate DIND (median 12.4 cm3) and patients without DIND (median 10.3 cm3; p < 0.001). Intraparenchymal hemorrhage and intraventricular hemorrhage were not associated with DIND. All 13 patients with cisternal volumes greater than 20 cm3 developed DIND, compared with 15 of 27 patients with volumes less than 20 cm3 (p = 0.004). CONCLUSIONS: The authors developed a simple and potentially widely applicable method to quantify SAH on CT scans. A greater volume of cisternal hemorrhage on an admission CT scan in patients with Fisher Grade 3 aneurysmal SAH is highly associated with DIND. A threshold of cisternal hemorrhage volume (> 20 cm3) may exist above which patients are very likely to develop DIND. Prospective application of software-based volumetric quantification of cisternal SAH may predict which patients will develop DIND.