The value of repeat cerebral angiography in subarachnoid haemorrhage

The diagnostic yield of repeat computed tomography angiography in cases of spontaneous subarachnoid haemorrhage after negative initial digital subtraction angiography

Purpose

It is currently unclear how useful repeat computed tomography angiography (CTA) is in spontaneous subarachnoid haemorrhage (SAH) patients after negative initial digital subtraction angiography (DSA). The purpose of this study is to assess the yield of repeat CTA for the detection of causative vascular lesions in patients with SAH in whom there has been a negative initial DSA.

Material and methods

This observational retrospective study was carried out from January 2013 to July 2022 at a single institution. Analysis of the SAH pattern on unenhanced CT showed that patients were divided into perimesencephalic SAH and diffuse SAH groups. A repeat CTA was performed on all spontaneous SAH patients who had a nega-tive initial CTA and DSA within a 2-week period. An interventional neuroradiologist and a diagnostic radiologist examined all images to search for causative vascular abnormalities.

Results

Forty-seven patients were included in our study, with a median age of 55 years and a range of 28-81 years. Thirty-seven had diffuse SAH (66%), and 16 had perimesencephalic SAH (34%). The repeat CTA revealed 2 causa-tive vascular lesions (a right PICA aneurysm and a mycotic aneurysm) in 2 separate patients (yield of 4.3%), both of whom had diffuse SAH (yield of 6.5%). In retrospect, none of these vascular lesions were evident in the initial CTA and DSA. No evidence of re-bleeding was observed in the follow-up period.

Conclusions

It is beneficial to repeat CTA when evaluating patients with diffuse SAH who initially present with nega-tive initial DSA. For occult aneurysms, the diagnostic yield of the follow-up CTA is 6.5%.

Midterm Follow-Up of 20 Consecutive Patients with Nonaneurysmal Subarachnoid Hemorrhage of Unknown Origin in a Single-Center: Two Cases of De Novo Development of Dural Arteriovenous Fistula

BACKGROUND AND PURPOSE

The mechanisms and prognosis of underlying subarachnoid hemorrhage of unknown origin remain unclear. Previous investigators have suggested a relationship between nonaneurysmal perimesencephalic subarachnoid hemorrhage and venous abnormalities like a primitive venous drainage of the basal vein of Rosenthal. We report the outcome of a midterm follow-up of 20 consecutive patients with nonaneurysmal subarachnoid hemorrhage of unknown origin, and 2 patients in whom the development of new dural arteriovenous fistulas after subarachnoid hemorrhage of unknown origin were detected during follow-up.

METHODS

All patients who were admitted to our hospital for nontraumatic subarachnoid hemorrhage between April 2008 and March 2016 were retrospectively analyzed.

RESULTS

Of 705 patients included in the study, 20 (2.8%) were diagnosed with nontraumatic subarachnoid hemorrhage of unknown origin. During the follow-up periods, there was no rebleeding. Although 18 patients did not show any vascular abnormalities, the other 2 patients were diagnosed with dural arteriovenous fistula. Both fistulas were successfully treated with endovascular embolization.

CONCLUSIONS

Subarachnoid hemorrhage of unknown origin had a low incidence rate, and its clinical course was excellent without rebleeding. Although no vascular abnormalities were observed during the patients' initial admission, venous lesions might have been involved in both subarachnoid hemorrhages and delayed dural arteriovenous fistulas. Here, the possible pathogenesis is discussed with a review of the literature.

Subarachnoid hemorrhage with negative initial catheter angiography: a review of 254 cases evaluating patient clinical outcome and efficacy of short- and long-term repeat angiography

BACKGROUND

Subarachnoid hemorrhage (SAH) is found to have no vascular origin by initial catheter angiography in approximately 15% of cases. The most appropriate course for the type and frequency of additional diagnostic workup remains controversial.

OBJECTIVE

To retrospectively assess the diagnostic yield of short-term and long-term repeat catheter angiography in the era of advanced imaging.

METHODS

Between 2003 and 2011, 254 consecutive patients diagnosed with SAH had negative initial angiography. SAH was perimesencephalic (PM) in 46.5% and nonperimesencephalic (NPM) in 53.5%. Angiography was repeated at 1-week (short-term) and 6-week (long-term) intervals from the initial negative angiogram.

RESULTS

Ten of 254 patients had a vascular source of hemorrhage on short-term follow-up angiography with a diagnostic yield of 3.9%. One hundred seventy-four patients with negative findings on the first 2 angiograms received a third angiogram, and 7 of these patients were found to have a vascular abnormality. The estimated yield of this third angiogram was 4.0%. The overall diagnostic yield of repeat angiography was 0% in the PM group and 12.5% in the NPM group. The diagnostic yield of short-term and long-term follow-up angiography in patients with NPM SAH was 7.3% and 7.8%, respectively. NPM patients were more likely to experience vasospasm and hydrocephalus requiring external ventricular drainage or cerebrospinal fluid diversion than PM patients.

CONCLUSION

Our results support a protocol of short-term and long-term angiographic follow-up in patients with NPM SAH and negative initial angiography. Aggressive protocols of follow-up angiography may not be necessary in patients with PM SAH.

Diagnostic yield of catheter angiography in patients with subarachnoid hemorrhage and negative initial noninvasive neurovascular examinations

BACKGROUND AND PURPOSE

The yield of DSA in patients with SAH and negative initial noninvasive neurovascular examinations (CTA or MRA) is not well-understood. This study aimed to determine the yield of DSA for the detection of causative vascular lesions in this clinical scenario.

MATERIALS AND METHODS

We examined the yield of DSA for the detection of causative vascular lesions in a cohort of patients presenting to our institution with SAH and negative initial noninvasive neurovascular examinations during a 5-year period. Two experienced neuroradiologists independently evaluated the NCCT to determine the SAH pattern (diffuse, perimesencephalic, or peripheral sulcal) and the catheter angiograms to assess the presence of a causative vascular lesion.

RESULTS

Fifty-five patients were included in the study, with a mean age of 58.2 years (median, 58 years; range, 25-88 years). Twenty-eight patients were men (50.9%), and 27 were women (49.1%). The initial noninvasive examination was a CTA in 47 patients (85.5%) and an MRA in 8 patients (14.5%). Thirty-three patients had diffuse SAH (60%); 11, perimesencephalic SAH (20%); and 11, peripheral sulcal SAH (20%). DSA demonstrated a causative vascular lesion in 6 patients (10.9%), 5 of whom had diffuse SAH (yield of 15.2%) and 1 of whom had peripheral sulcal SAH (yield of 9.1%). No causative vascular lesions were found in patients with perimesencephalic SAH.

CONCLUSIONS

DSA is a valuable tool in the evaluation of patients with diffuse and peripheral sulcal SAH who have negative initial noninvasive neurovascular examinations, demonstrating a causative vascular lesion in 15.2% and 9.1% of patients, respectively.

Diagnostic yield of computed tomography angiography and magnetic resonance angiography in patients with catheter angiography-negative subarachnoid hemorrhage

OBJECT

The yield of CT angiography (CTA) and MR angiography (MRA) in patients with subarachnoid hemorrhage (SAH) who have a negative initial catheter angiogram is currently not well understood. This study aims to determine the yield of CTA and MRA in a prospective cohort of patients with SAH and a negative initial catheter angiogram.

METHODS

From January 1, 2005, until September 1, 2010, the authors instituted a prospective protocol in which patients with SAH-as documented by noncontrast CT or CSF xanthochromia and a negative initial catheter angiogram- were evaluated using CTA and MRA to assess for causative cerebral aneurysms. Two neuroradiologists independently evaluated the noncontrast CT scans to determine the SAH pattern (perimesencephalic or not) and the CT and MR angiograms to assess for causative cerebral aneurysms.

RESULTS

Seventy-seven patients were included, with a mean age of 52.8 years (median 54 years, range 19-88 years). Fifty patients were female (64.9%) and 27 male (35.1%). Forty-three patients had nonperimesencephalic SAH (55.8%), 29 patients had perimesencephalic SAH (37.7%), and 5 patients had CSF xanthochromia (6.5%). Computed tomography angiography demonstrated a causative cerebral aneurysm in 4 patients (5.2% yield), all of whom had nonperimesencephalic SAH (9.3% yield). Mean aneurysm size was 2.6 mm (range 2.1-3.3 mm). Magnetic resonance angiography demonstrated only 1 of these aneurysms. No causative cerebral aneurysms were found in patients with perimesencephalic SAH or CSF xanthochromia.

CONCLUSIONS

Computed tomography angiography is a valuable adjunct in the evaluation of patients with nonperimesencephalic SAH who have a negative initial catheter angiogram, demonstrating a causative cerebral aneurysm in 9.3% of patients.

Diagnostic yield of repeat catheter angiography in patients with catheter and computed tomography angiography negative subarachnoid hemorrhage

BACKGROUND

The yield of repeat catheter angiography in patients with subarachnoid hemorrhage (SAH) who have negative initial catheter and computed tomography (CT) angiograms is not well understood.

OBJECTIVE

To determine the yield of repeat catheter angiography in a prospective cohort of patients with SAH and negative initial catheter and CT angiograms.

METHODS

From January 1, 2005, until September 1, 2010, we instituted a prospective protocol in which patients with SAH documented by noncontrast CT (NCCT) or cerebrospinal fluid (CSF) xanthochromia and negative initial catheter and CT angiograms were evaluated with repeat catheter angiography 7 days and 3 months after presentation to assess for causative vascular abnormalities.

RESULTS

Seventy-two patients were included, with a mean age of 53.1 years (median, 53.5 years; range, 19-88 years). Forty-six patients were female (63.9%) and 26 male (36.1%). Thirty-nine patients had nonperimesencephalic SAH (54.2%), 29 patients had perimesencephalic SAH (40.3%), and 4 patients had CSF xanthochromia (5.5%). The first repeat catheter angiogram performed 7 days after presentation demonstrated a causative vascular abnormality in 3 patients (yield of 4.2%), 2 of which had nonperimesencephalic SAH (yield of 5.1%), and 1 had perimesencephalic SAH (yield of 3.4%). The second repeat catheter angiogram performed in 43 patients (59.7%) did not demonstrate any causative vascular abnormalities. No causative abnormalities were found in patients with CSF xanthochromia.

CONCLUSION

Repeat catheter angiography performed 7 days after presentation is valuable in the evaluation of patients with SAH who have negative initial catheter and CT angiograms, demonstrating a causative vascular abnormality in 4.2% of patients.

CT angiography with three-dimensional techniques for the early diagnosis of intracranial aneurysms. Comparison with intra-arterial DSA and the surgical findings

INTRODUCTION

Cerebral CT angiography (CTA) is an established method applied to both the detection and treatment planning of intracranial aneurysms. The aim of our study was to compare CTA and digital subtraction angiography (DSA) findings with the surgical results mainly in patients with acute SAH and to evaluate the clinical usefulness of CTA.

MATERIALS AND METHODS

During the last 2 years, 82 consecutive patients were admitted under clinical symptoms and signs suggestive of harboring an intracranial aneurysm. CT angiography performed immediately afterwards the plain CT, while DSA was performed within the first 48 h of admission. All aneurysms detected were confirmed during surgery or endovascular embolization. Repeat DSA was performed in all patients having both the initial CTA and the DSA 15 days after the onset of symptoms negative. CT angiograms and conventional angiographies were studied by a consensus of two radiologists for each technique, who performed aneurysm detection, morphological features characterization and evaluation of the technique.

RESULTS

Surgical or/and endovascular treatment was performed in 45 patients and 53 aneurysms were confirmed. Using 3D-CT angiography, we detected 47 aneurysms in 42 patients. Conventional angiography depicted 43 aneurysms in 39 patients. The sensitivity of CTA for the detection of all aneurysms versus surgery was 88.7%, the specificity 100%, the positive predictive value (PPV) 100%, the negative predictive value (NPV) 80.7% and the accuracy 92.3%. Accordingly, the sensitivity of DSA was 87.8%, the specificity 98%, the PPV 97.7%, the NPV 89.1% and the accuracy 92.9%. Considering aneurysms > or =3 mm, CTA showed a sensitivity ranging from 93.3 to 100%, equal to that of DSA.

CONCLUSION

Cerebral CT angiography has an equal sensitivity to DSA in the detection of intracranial aneurysms >3 mm. It has also 100% detection rate in AcoA and MCA bifurcation aneurysms, while some locations, like posterior communicating artery aneurysms, remain problematic. The delineating features of each aneurysm are better depicted with CTA due to 3D visualization. The use of digital subtraction angiography as a diagnostic tool can be limited in equivocal cases.

Diagnosis of perimesencephalic nonaneurysmal subarachnoid hemorrhage with computed tomography

OBJECTIVE

In 4% to 31% of patients with acute subarachnoid hemorrhage (SAH), no underlying cause is identified. Blood is restricted to the perimesencephalic cisterns in about two thirds of these patients. These patients are identified as having perimesencephalic nonaneurysmal subarachnoid hemorrhage (PNSAH), a syndrome based on the interpretation of computed tomography (CT) findings on admission, with an excellent prognosis, far better than other patients with SAH with or without an aneurysm. However, the diagnosis is subject to interrater variability, and differentiation between PNSAH and ruptured supratentorial aneurysm by means of CT has not been investigated. Therefore we investigated the validity of prediction of PNSAH with CT scan.

METHODS

A total of 303 consecutive patients, admitted within 72 hours after the initial bleeding with symptoms and signs of spontaneous SAH, which was confirmed by CT or spectrophotometric analysis of the cerebrospinal fluid (CSF) in whom either a selective 4-vessel angiogram (n = 293) or postmortem examination (n = 10) was performed, were studied.

RESULTS

We found an interrater agreement for the diagnosis perimesencephalic nonaneurysmal subarachnoid hemorrhage of 93% and a kappa value of 0.65. Sensitivity was 30% for observer 1 and 46% for observer 2. The positive predictive value was 73% for observer 1 and 76% for observer 2. Among those diagnosed as having PNSAH, we found vertebrobasilar artery aneurysms in 19% (both raters) and internal carotid artery aneurysms in 5% (observer 1) and 8% (observer 2).

CONCLUSION

We conclude that PNSAH can be distinguished on CT in the majority of patients; however, the angiographical management in PNSAH should not differ from other SAHs.

Preoperative evaluation of intracranial aneurysms: usefulness of intraarterial 3D CT angiography and conventional angiography with a combined unit--initial experience

PURPOSE

To assess the usefulness of intraarterial computed tomographic (CT) angiography in conjunction with digital subtraction angiography (DSA) by using a combined CT and angiographic unit in the preoperative evaluation of intracranial aneurysms.

MATERIALS AND METHODS

Prospectively, 22 patients with or without subarachnoid hemorrhage underwent CT angiography in conjunction with DSA. Two radiologists independently evaluated DSA and CT angiographic images. Referring neurosurgeons were questioned as to how the additional information provided by CT angiography changed patient treatment.

RESULTS

Intraarterial CT angiography was superior to DSA for use in aneurysm detection in three (12%) of 26 aneurysms and for delineation of aneurysm shape, neck, and location in more than half. In 14 (64%) of 22 patients, CT angiography demonstrated 18 additional findings: a very small aneurysm (n = 2), aneurysm shape and neck (n = 6), relationship of the aneurysm to adjacent arteries or bone structure (n = 8), and branches deriving from the aneurysm (n = 2). In four (27%) of 15 patients who underwent surgery or embolization, additional information obtained at CT angiography affected the treatment. CT angiography failed to clearly demonstrate an aneurysm adjacent to bone structures and small perforators, which were derived from the parent artery.

CONCLUSION

Intraarterial CT angiography is useful for preoperative evaluation of intracranial aneurysms as a supplement to DSA.

Perimesencephalic nonaneurysmal subarachnoid hemorrhage: review of the literature

OBJECTIVE

A critical review of the literature on the incidence, presentation, diagnosis, and prognosis of perimesencephalic nonaneurysmal subarachnoid hemorrhage.

METHODS

Review of the relevant literature.

CONCLUSION

The importance of early computed tomography (< 3 d), anatomy of the perimesencephalic and neighboring cisterns, and adequate four-vessel angiography are discussed. Treatment strategies, including the avoidance of repeated angiographic studies and surgical exploration, are presented.