Angiogram-negative Subarachnoid Hemorrhage Research Articles

The risk assessment of antiplatelet medications in angiogram-negative subarachnoid hemorrhage

Objective The influence of antiplatelet medications on prognosis after non-aneurysmal subarachnoid hemorrhage(SAH) is unknown.This study aimed to evaluate the risk of antiplatelet mdications in developing SAH. Methods 420 patients who underwent catheter cerebral angiography after presenting with nontraumatic SAH were included.Outcomes were assessed by using the modified Rankin scale. Results A total of 420 patients underwent catheter angiography for evaluation of SAH.Of these, 63 cases (15%) were angiogram-negative.The fraction of patients presenting with angiogram-negative SAH as well as the frequency of antiplatelet use among these patients significantly increased during the study period.Antiplatelet use was more commonly associated with angiogram-negative SAH(18/63, 28.6%) than with angiogram-positive SAH(39/357, 11%; P=0.001). At 14 days after presentation, poor outcome was significantly more frequent among patients who took antiplatelet agents(20/63, 31.7%) than among those who did not(12/63, 20%; P=0.017). Conclusion Antiplatelet medication use is associated with poor early, but not late, outcomes after angiogram-negative SAH.More studies are needed to confirm this association. Key words: Platelet aggregation inhibitors; Negative reactions; Cerebral angiography; Subarachnoid hemorrhage

Analysis of Hemorrhage Volumes After Angiogram-Negative Subarachnoid Hemorrhage

Antiplatelet medication use is associated with worsened outcome after angiogram-negative subarachnoid hemorrhage (SAH). It has been hypothesized that these worsened outcomes may be the result of an association between antiplatelet medication use and increased hemorrhage volumes after angiogram-negative SAH. To test this hypothesis, we performed volumetric analysis of computed tomography (CT)-defined hemorrhage after angiogram-negative SAH. This was a retrospective analysis of patients presenting with nontraumatic, angiogram-negative SAH in the Columbia University Subarachnoid Hemorrhage Outcomes database between 2000 and 2013. SAH volumes on admission head CT scans were measured using the MIPAV software package, version 7.20 in a semiautomated fashion. A total of 108 presenting CT scans from patients with angiogram-negative SAH were analyzed. The mean hemorrhage volume was 14.3 mL in the patients with a history of antiplatelet medication use, compared with 6.8 mL in those with no history of antiplatelet use. This difference was found to be significant (P= 0.0029). Antiplatelet medication use is associated with increased SAH volumes in patients with angiogram-negative SAH. Increased hemorrhage volumes may contribute to poor outcomes in this patient population. Prospective studies are warranted to confirm this association.

Angiogram Negative Subarachnoid Hemorrhage: Outcomes and the Necessity of Repeated Angiogram

Objectives: This retrospective case-control study was conducted to ascertain the clinical course and outcomes of the patients with angiogram-negative SAH, and to evaluate the necessity of repeat DSA in subgroups of patients with SAH with negative initial DSA. Patients and Methods: Retrospective analysis of clinical records and imaging of all patients presenting to our institution with nontraumatic SAH. Results were analyzed for presenting grades, blood distribution, outcomes, repeat DSA and findings. Bleeding pattern was determined from computed tomography (CT) and was categorized as perimesencephalic (PMN), diffuse, cortical. The criteria for bleeding pattern categorization were adapted from previous studies. PMN group included those with hemorrhage limited in one or more basal cisterns. Diffuse group included those with hemorrhage extending to the sylvian fissure, peripheral sulci, or intraventricular space. Cortical hemorrhage is defined as isolated blood in the peripheral sulci without hemorrhage in the basal cisterns. Results: 37 patients with proven nontraumatic SAH of which 9 (24.3%) had no vascular cause identified on their initial angiogram were identified. The blood distribution was perimesencephalic in 2, diffuse in 6, and cortical in 1. 7 patients (16%) underwent repeat cranial DSA. 2 of the repeat angiograms showed an underlying etiology for the SAH. Overall, the false-negative rate of the initial DSA was 28.57% (2/7 patients). 2 patient with SAH underwent 3rd DSA and no aneurysms were found. Patients with angiogramnegative SAH have better admitting consciousness (p=0.040306), different blood distribution pattern (p=0.023), better outcomes (p=0.004402). We also performed a review of the literature and meta-analysis of the data therein. We compared outcome between PMN subgroup and the diffuse subgroup and false negative rates on repeated DSA in the PMN subgroup and the diffuse subgroup. The meta-analysis revealed better outcome in PMN subgroup and significant lower false negative rate of detection aneurysm after repeated DSA in the patients with PMN. Conclusion: In the line with the results of the current study, angiogram negative subarachnoid hemorrhage has generally more benign course than SAH of known cause. We should be highly suspicious of patients with initial angiogram negative SAH, especially those with a diffuse SAH pattern. Repeat DSA is necessary for angiogram negative SAH

Sexual activity as a trigger for intracranial hemorrhage.

Intracranial hemorrhage (ICH) has been reported in association with sexual activity. A case-series of patients with ICH following sexual activity is presented to further elucidate the role of the physiologic sexual response as a trigger of ICH. A retrospective review of the medical record was performed, identifying patients presenting with ICH temporally related to sexual activity. Clinical and radiographic data were collected and reported. Sixteen patients presented with non-traumatic ICH temporally related to sexual activity. Eight (50%) patients presented with aneurysmal subarachnoid hemorrhage, four (25%) with angiogram-negative subarachnoid hemorrhage, two (12.5%) with a ruptured arteriovenous malformation, and two (12.5%) with an intracerebral basal ganglia hemorrhage. Overall average age was 49.9 (range, 28-74) years. Sexual activity involved male-female intercourse in 14 (87.5%) patients and masturbation in 2 (12.5%) patients. Sexual-activity-related ICH is rare and includes various etiologies. The human sexual response in associated with dramatic increases in arterial blood pressure, which likely underlies the association.

Cerebral Angiography for Evaluation of Patients with CT Angiogram-Negative Subarachnoid Hemorrhage: An 11-Year Experience.

CT angiography is increasingly used to evaluate patients with nontraumatic subarachnoid hemorrhage given its high sensitivity for aneurysms. We investigated the yield of digital subtraction angiography among patients with SAH or intraventricular hemorrhage and a negative CTA. An 11-year, single-center retrospective review of all consecutive patients with CTA-negative SAH was performed. Noncontrast head CT, CTA, DSA, and MR imaging studies were reviewed by 2 experienced interventional neuroradiologists and 1 neuroradiologist. Two hundred thirty patients (mean age, 54 years; 51% male) with CTA-negative SAH were identified. The pattern of SAH was diffuse (40%), perimesencephalic (31%), sulcal (31%), isolated IVH (6%), or identified by xanthochromia (7%). Initial DSA yield was 13%, including vasculitis/vasculopathy (7%), aneurysm (5%), arteriovenous malformation (0.5%), and dural arteriovenous fistula (0.5%). An additional 6 aneurysms/pseudoaneurysms (4%) were identified by follow-up DSA, and a single cavernous malformation (0.4%) was identified by MRI. No cause of hemorrhage was identified in any patient presenting with isolated intraventricular hemorrhage or xanthochromia. Diffuse SAH was due to aneurysm rupture (17%); perimesencephalic SAH was due to aneurysm rupture (3%) or vasculitis/vasculopathy (1.5%); and sulcal SAH was due to vasculitis/vasculopathy (32%), arteriovenous malformation (3%), or dural arteriovenous fistula (3%). DSA identifies vascular pathology in 13% of patients with CTA-negative SAH. Aneurysms or pseudoaneurysms are identified in an additional 4% of patients by repeat DSA following an initially negative DSA. All patients with CT-negative SAH should be considered for DSA. The pattern of SAH may suggest the cause of hemorrhage, and aneurysms should specifically be sought with diffuse or perimesencephalic SAH.

O-034 cerebral angiography for evaluation of patients with ct angiogram negative subarachnoid hemorrhage: an 11-year experience

Background and purpose CT Angiography (CTA) is increasingly used to evaluate non-traumatic subarachnoid hemorrhage (SAH) given its excellent sensitivity for intracranial aneurysms. We determined the yield of Digital Subtraction Angiography (DSA) among patients presenting with SAH or intraventricular hemorrhage (IVH) and a negative CTA. Methods A 11-year, single-center retrospective review of all consecutive patients with CTA-negative SAH was performed. Non-contrast head CT, CTA, DSA, and MRI studies were reviewed by three experienced neuroradiologists and interventional neuroradiologists. Results 230 patients (mean age 54 years, 51% male) who presented with CTA-negative SAH were identified. The pattern of SAH on presentation was diffuse (40%), perimesencaphlic (31%), sulcal (31%), isolated IVH (6%), or identified by xanthochromia (7%). Initial DSA yield was 13%, including vasculitis/vasculopathy (7%), aneurysm (5%), arteriovenous malformation (0.5%), and dural arteriovenous fistula (0.5%). An additional 6 aneurysms/pseudoaneurysms (3%) were identified by follow-up DSA, and a single cavernous malformation (0.4%) was identified by MRI. No cause of hemorrhage was identified in patients presenting with isolated IVH or xanthochromia. Diffuse SAH was due to aneurysm rupture (17%); perimesencephalic SAH was due to aneurysm rupture (3%) or vasculitis/vasculopathy (1.5%); and sulcal SAH was due to vasculitis/vasculopathy (32%), arteriovenous malformation (3%), or dural arteriovenous fistulae (3%). Conclusions DSA identifies vascular pathology in 13% of patients with CTA-negative SAH. Aneurysms or pseudoaneurysms are identified in an additional 3% of patients by follow-up DSA following an initially negative DSA. The pattern of SAH may suggest the cause of hemorrhage, and aneurysms should be sought in patients with diffuse or perimesencephalic SAH. Disclosures J. Heit: None. G. Pastena: None. R. Nogueira: None. A. Yoo: None. T. Leslie-Mazwi: None. J. Hirsch: None. J. Rabinov: None.

Glioblastoma and intracranial aneurysms: Case report and review of literature

Background:There is a paucity of data on the association of glioblastoma multiforme (GBM) with intracranial aneurysms. It is an important clinical entity for physicians to be aware of and its presence illustrates several critical features of the pathophysiology of malignant glioma. In this article we present a case of a middle cerebral artery (MCA) pseudoaneurysm that occurred in a patient with recurrent GBM as well discuss the current literature relating to this unique combination of pathologies.Case Description:The authors present a case of a MCA pseudoaneurysm that developed in a patient with recurrent GBM and discuss the current literature. The authors identified 19 reports describing 23 patients harboring both GBM and an intracranial aneurysm.Conclusion:Several theories stand to explain the coincidental occurrence of intracranial aneurysms and GBM. The treating physician should be aware of this association when patients with intraaxial tumors present with unusual manifestation such as an intratumoral hemorrhage or angiogram negative subarachnoid hemorrhage. No guidelines exist to assist in the management of such patients; therefore, authors have attempted to address this issue using a classification and treatment algorithm.

The role of antiplatelet medications in angiogram-negative subarachnoid hemorrhage.

The use of antiplatelet medications has greatly expanded and this has been associated with an increased rate of complications after aneurysmal subarachnoid hemorrhage (SAH). The influence of antiplatelet medications on outcomes after non-aneurysmal SAH is unknown. To analyze the frequency and impact on outcome of antiplatelet medication use among patients with angiogram-negative SAH. An analysis of patients within the Columbia University SAH Outcomes Project database was performed. All patients who underwent catheter cerebral angiography after presenting with nontraumatic SAH between 1996 and 2013 were included. Outcomes were assessed by using the modified Rankin Scale. A total of 1351 patients underwent catheter angiography for evaluation of SAH. Of these, 173 (13%) were designated angiogram-negative. The fraction of patients presenting with angiogram-negative SAH as well as the frequency of antiplatelet use among these patients significantly increased during the study period. Antiplatelet use was more commonly associated with angiogram-negative SAH than with angiogram-positive SAH (27% vs 14%, P = .001). At 14 days after presentation, poor outcome was significantly more frequent among patients who took antiplatelet agents than among those who did not (38% vs 20%, P = .017). This effect was also seen after multivariate analysis (odds ratio, 2.58; P = .034), although no difference was observed by 12 months (P > .05). Antiplatelet medication use is associated with poor early, but not late, outcomes after angiogram-negative SAH. Corresponding increased rates of antiplatelet medication use and angiogram-negative SAH may be related. Additional studies are needed to confirm this association.

Value of delayed MRI in angiogram-negative subarachnoid haemorrhage

To assess the efficacy of delayed magnetic resonance imaging (MRI) in identifying a structural cause for angiogram-negative subarachnoid haemorrhage. All patients presenting with spontaneous subarachnoid haemorrhage who had negative computed tomography (CT) angiography and catheter angiography between 2006 and 2012 were reviewed. During the 6 year period, 1023 angiograms were performed for a new presentation of subarachnoid haemorrhage. Of these, 242 (23.7%) did not show a cause for the haemorrhage. A second catheter angiogram was performed in 48 patients, and aneurysms were identified in two patients. Of the remaining 240 patients, 131 underwent a subsequent MRI brain. One hundred and five (80.2%) MRI examinations were performed 4 or more weeks after angiography. In two patients, cavernomas were identified as the likely bleeding source. In both patients, the pattern of subarachnoid haemorrhage surrounding a small intraparenchymal haemorrhage on the initial CT suggested the diagnosis. Thirty-nine patients underwent MRI of the cervical spine, none of which identified a cause for the haemorrhage. None of the patients re-presented to our centre during the 6 year study period. Delayed MRI following angiogram-negative subarachnoid haemorrhage has a low (1.5%) yield and is not routinely necessary. MRI may be useful to characterize the diagnosis in patients with clinical or radiological features of an underlying abnormality such as a cavernoma.

Angiogram-negative subarachnoid hemorrhage: is it a correct definition?

Angiogram-negative subarachnoid hemorrhage: is it a correct definition?

Angiogram negative subarachnoid haemorrhage: Outcomes and the role of repeat angiography

Angiogram negative sub-arachnoid haemorrhage (SAH) is generally considered to have a more benign course than SAH of known cause. There is also variability from centre to centre as to what proportion of angiogram negative SAH patients undergo repeat Digital Subtraction Angiography (DSA). We performed a retrospective study looking at the last four years' of SAH patients at our institution in order to ascertain the clinical course, the nature and results of repeat imaging. Retrospective analysis of clinical records and imaging of all patients presenting to our institution with non-traumatic SAH between April 2008 and February 2012 was performed. Results were analysed for presenting grades, blood distribution, complications, outcomes, repeat imaging modalities and findings. 459 patients with proven non-traumatic SAH of which 50 (11%) had no vascular cause identified on their initial angiogram were identified. The blood distribution was perimesencephalic in 17, non-perimesencephalic in 23, and 10 patients were computed tomography (CT) Negative with a positive lumbar puncture. Eight (16%) patients were complicated by hydrocephalus and 2 (4%) were complicated by vasospasm. Eight patients (16%) underwent repeat cranial DSA with a high suspicion in a multi-disciplinary team setting. None of the repeat angiograms showed an underlying aetiology for the SAH. 76% of patients had a Glasgow Outcome Score of 5 at 6 months. There were no rebleeds. While generally more benign, angiogram negative subarachnoid haemorrhage can have a complicated clinical course. In our experience repeat DSA should be reserved for cases in which there is significant suspicion of occult vascular lesion. However, evidence-based guidelines are needed to aid the development of management protocols for angiogram-negative SAH and ensuring optimal patient outcomes.

Angiogram-Negative Subarachnoid Hemorrhage: Outcomes Data and Review of the Literature

Spontaneous subarachnoid hemorrhage (SAH) is most commonly caused by rupture of a saccular aneurysm or other structural pathologies. Occasionally, no structural cause for the hemorrhage can be identified by radiographic imaging. These hemorrhages, termed angiogram-negative SAH, are generally considered to have a better prognosis than aneurysmal SAH. Angiogram-negative SAH subgroups include benign perimesencephalic SAH (PMH) and aneurysmal-type SAH. Outcome data for these subgroups differ from those for the group as a whole. We report data for 31 patients who presented to our institution from 2006 to the present. We performed a retrospective chart review, and report outcome data that include rates of rehemorrhage, hydrocephalus, vasospasm, permanent ischemic deficits, headaches, and outcomes based on modified Rankin Scale scores. We also performed a review of the literature and meta-analysis of the data therein. We compared rates of complications in the PMH subgroup and the diffuse-type hemorrhage subgroup. The chart review revealed no poor outcomes and no rehemorrhages in the patients with PMH. In the diffuse hemorrhage subgroup, 1 patient had a rehemorrhage and 2 patients had a poor outcome. Our literature review found an OR of 6.23 for a good outcome for PMH versus diffuse-type hemorrhage, and an OR of 2.78 for rehemorrhage in PMH versus diffuse-type hemorrhage. Angiogram-negative SAH is not a benign entity. Complications are present but are significantly reduced, and outcomes are improved, compared with aneurysmal SAH.

Angiogram-Negative Subarachnoid Hemorrhage: Relationship Between Bleeding Pattern and Clinical Outcome

Angiogram-negative subarachnoid hemorrhage (anSAH) accounts for 15% of spontaneous SAH. Recent studies suggest the outcome and diagnostic yield in anSAH differ based on initial bleeding pattern. We present a single-center experience in managing patients with SAH and negative initial digital-subtracted angiogram (DSA). Records of all patients with anSAH were reviewed. Bleeding pattern was determined from computed tomography (CT) and was categorized as perimesencephalic (PMN), diffuse, cortical, or xanthochromia (blood not detectable by CT). Diagnostic yield, in-hospital complications, and outcome parameters were analyzed. Of 352 patients admitted with spontaneous SAH from 2003 to 2008, 68 (19.3%) had negative initial DSA. Mean age was 59.5 ± 14, and 33 were female. By CT, 27 (39.7%) patients exhibited PMN SAH, 33 (48.5%) diffuse SAH, 6 (8.8%) cortical SAH, and 2 (2.9%) xanthochromia only. Sixty-one patients had good Hunt and Hess (H/H) grades (I-III) and seven had poor grades (IV-V). Additional diagnostic studies included repeat angiogram (54), brain and C-spine magnetic resonance imaging (20), and repeat CTA (15). A structural bleeding cause was determined in six (8.8%) patients, 4 of which had diffuse SAH and 2 cortical SAH. Among these, two aneurysms (2.9%) were detected and surgically clipped, and both had diffuse SAH. Twenty-nine patients (42.6%) experienced medical complications, with infection (18), cardiovascular problems (12), and vasospasm (10) being the most frequent events. Additional surgeries included 13 ventriculoperitoneal shunts, 4 tracheostomies, and 9 gastric tube placements. Favorable outcome (mRS = 0-2) was recorded in 49 (72.1%) patients and unfavorable (3-6) in 19 (17.49%), with 1 (1.2%) in-hospital death. Multivariable logistic regression revealed older age and diffuse bleeding pattern were significant predictors of unfavorable outcome. The overall incidence of true aneurysms in patients with angiogram-negative SAH is low (2.9%). Initial bleeding pattern strongly correlates with diagnostic yield and clinical outcome. Diffuse bleeding pattern is associated with significantly higher diagnostic yield, more in-hospital complications, and worse clinical outcome. Patients with initial imaging characteristics other than diffuse pattern SAH developed few disease related complications, with the majority of in-hospital adverse events treatment related.

Subarachnoid hemorrhage and negative angiography: clinical course and long-term follow-up

The aim of this study was to investigate the long-term natural history of nontraumatic angiogram-negative subarachnoid hemorrhage with typical pretruncal (P-SAH) and diffuse (D-SAH) pattern of hemorrhage. A retrospective review of 102 patients who experienced angiographically negative SAH at our institution was undertaken (11.6% of 882 spontaneous SAH). Follow-ups were obtained at 7.9 to 16 years. In the D-SAH group, 11 patients (13.9%) out of 79 had an aneurysm, and four (5.1%) had rebleeding episodes. In the P-SAH group, the second angiography was negative in all of the 23 cases, and no rebleeding episodes were recorded. The long-term follow-up confirms that P-SAH is a benign disease. A second angiography could not be necessary. D-SAH is probably due to an aneurysm that thrombose early after the bleeding. At short-term follow-up, the sack could frequently recanalize and rebleed, whereas a late follow-up shows that rebleeding is very rare.

Low Diagnostic Yield of Non-Invasive Imaging In Angiogram-Negative Subarachnoid Hemorrhage

Objectives: We describe the application of fundamental quality improvement methods to medical handoffs in order to improve resident learning and clinical training.Methods: We retrospectively reviewed 226 non-traumatic SAH patients admitted to our institution from January 1, 2007 to June 1, 2009. Imaging data were abstracted from medical charts.Results: Of the 226 SAH patients, 45 (19.9%) had no aneurysm on initial angiography. Of these angiogram-negative SAH patients, 12 (26.7%) were perimesencephalic SAH and 33 (73.3%) were NPAN-SAH. An average of 3.2 non-invasive studies was performed on each patient. In these 142 additional non-invasive studies, there was no additional diagnostic yield in finding the source of SAH.Conclusions: Though non-perimesencephalic angiogram-negative SAH had a worse prognosis compared to perimesencephalic SAH, additional non-invasive neuroimaging provided no diagnostic yield in either patient population.

Clinical course of nontraumatic, nonaneurysmal subarachnoid hemorrhage: a single-institution experience

Angiogram-negative subarachnoid hemorrhage (SAH) accounts for 15% of nontraumatic SAH and has been reported with low morbidity and mortality rates. We report on a large series of patients with angiogram-negative SAH who experienced an atypical nonbenign clinical course. Between December 2001 and November 2006, 95 patients with spontaneous nonaneurysmal SAH and negative initial angiographic evaluation were treated at the University of Florida. The authors retrospectively reviewed the patients' medical records and radiological images to determine associated morbidity and mortality. Aneurysms were found in 6 of the 95 patients on follow-up imaging after an initial negative angiogram (6.3% false negative rate); these patients were excluded leaving 89 patients as the study group. Hydrocephalus necessitating temporary CSF diversion developed in 22 of these patients (25%); 12 (13%) ultimately required permanent CSF diversion. Clinically significant vasospasm developed in 4 patients (4%), and 2 (2%) had cerebral infarctions. Three patients (3%) died. The authors' experience with a large series of angiogram-negative SAH patients who had an atypical nonbenign clinical course associated with hydrocephalus, vasospasm, stroke, and mortality differs significantly from previously published case series of angiogram-negative SAH.

Low Diagnostic Yield of Non-Invasive Imaging In Angiogram-Negative Subarachnoid Hemorrhage

Objectives: We describe the application of fundamental quality improvement methods to medical handoffs in order to improve resident learning and clinical training.Methods: We retrospectively reviewed 226 non-traumatic SAH patients admitted to our institution from January 1, 2007 to June 1, 2009. Imaging data were abstracted from medical charts.Results: Of the 226 SAH patients, 45 (19.9%) had no aneurysm on initial angiography. Of these angiogram-negative SAH patients, 12 (26.7%) were perimesencephalic SAH and 33 (73.3%) were NPAN-SAH. An average of 3.2 non-invasive studies was performed on each patient. In these 142 additional non-invasive studies, there was no additional diagnostic yield in finding the source of SAH.Conclusions: Though non-perimesencephalic angiogram-negative SAH had a worse prognosis compared to perimesencephalic SAH, additional non-invasive neuroimaging provided no diagnostic yield in either patient population.

Distal aneurysms of basilar perforating and circumferential arteries

Distal aneurysms of basilar perforating and circumferential arteries are exceedingly rare. The authors encountered one patient with a distal basilar perforating artery aneurysm and two with aneurysms arising from circumferential branches of the basilar artery (BA). The diagnostic features, microsurgical treatment, and outcomes in these three patients are described. The first patient, a 27-year-old man, presented with an angiogram-negative subarachnoid hemorrhage (SAH), and subsequent readmission for a new hemorrhage revealed a centrally thrombosed aneurysm arising from a basilar apex perforating artery. The second patient, a 68-year-old man, presented for follow-up evaluation 2 months after an angiogram-negative SAH, and an aneurysm was identified on a circumferential artery originating from the BA trunk. The third patient, a 2-year-old boy, presented with blunt head trauma and a pseudoaneurysm arising from a basilar apex circumferential artery. All three aneurysms were managed microsurgically with aneurysm trapping, via either an orbitozygomatic or an extended retrosigmoid approach. Occlusion of the distal perforating or circumferential artery was well tolerated in all cases, with no neurological sequelae resulting from surgery. Features common to all three aneurysms were dolichoectatic morphology, intraluminal thrombus, and SAH. These aneurysms may be difficult to diagnose given their small size and delayed filling on angiographic studies. Consequently, their presence in cases of angiogram-negative SAH may be underestimated. These aneurysms are not amenable to endovascular treatment, but excellent results can be obtained with microsurgical exposure and trapping.

Spontaneous subarachnoid haemorrhage with negative initial angiography: A review of 143 cases

The need for repeat angiography in patients with subarachnoid haemorrhage (SAH) who initially present with a negative angiogram is still debated. The aim of this study was to provide a management protocol for ‘angiogram-negative SAH’. From January 1986 to June 2004, 143 patients with SAH were admitted to our institution with negative initial angiograms. We classified the 143 patients into three groups: group I, with no SAH on CT scan, but confirmed by cerebrospinal fluid analysis; group II, with a perimesencephalic pattern of SAH; and group III, with a non-perimesencephalic pattern of SAH. Out of the 143 patients, 103 underwent repeat angiography, and 18 were found to have ruptured aneurysms that were not detected on the initial angiogram (false negative rate: 17.5% overall, 0% in group I, 1.5% in group II, and 45.9% in group III). Repeat angiography should be performed, particularly in patients who have a non-perimesencephalic SAH pattern, for detection of initially unrecognised ruptured aneurysms.

Midbrain Stroke With Angiogram-Negative Subarachnoid Hemorrhage Mimicking a Perimesencephalic Bleed

Angiogram-negative atraumatic subarachnoid hemorrhage (SAH) in a perimesencephalic pattern on computed tomography (CT) is associated with an almost invariably favorable prognosis with few rebleeds. We report a patient who exhibited a perimesencephalic hemorrhage pattern on CT and negative serial angiograms and who presented with severe neurologic disability from a concurrent midbrain stroke. We contend that both the acute infarction and hemorrhage arose from obliteration of a penetrating end artery. Possible etiologies of angiogram-negative SAH, including perimesencephalic hemorrhage, are discussed.