Clinical utility and cost-effectiveness of CT-angiography in the diagnosis of nontraumatic subarachnoid hemorrhage

The role of computed tomography angiogram in intracranial hemorrhage. Do the benefits justify the known risks in everyday practice?

BACKGROUND

Intracranial hemorrhage is a commonly encountered medical problem frequently evaluated by computed tomography angiography (CTA). In CTA, there is radiation exposure and possible adverse effects of intravenous contrast administration. Therefore, the yield of this diagnostic tool needs to be explored in a heterogeneous group of daily encountered patients to provide insight into the risks and benefits of CTA.

OBJECTIVE

To evaluate the role of cerebral CTA in patients with CT-confirmed or clinically suspected intracranial hemorrhage.

METHODS

This retrospective study included all patients who underwent cerebral CTA for evaluation of intracranial hemorrhage that was diagnosed by a plain CT scan or suspected clinically from January 1, 2010, to May 30, 2018. All the scans were evaluated for abnormalities of the cerebral arteries in the CTA.

RESULTS

One hundred twenty patients were included, 74 % were males, and the mean age was 46 years. Approximately 18 % were trauma patients. Overall, CTA was abnormal in 52 % of cases, aneurysms were found in 27 %, and arteriovenous malformation (AVM) in 8 %. Among 82 patients who had a hemorrhage on the plain CT scans, 54 % had normal CTA, 28 % showed aneurysm, and 11 % showed AVM. In trauma patients, the most common CTA finding was normality (48 %), followed by aneurysms (19 %) and dissection (14 %). In non-trauma patients, the most common CTA finding was normality (49 %), followed by aneurysms (28 %) and AVM (10 %).

CONCLUSIONS

CTA is a valuable diagnostic tool for intracranial hemorrhage because it detected abnormalities related to the hemorrhage in 42 % of patients. However, because more than half (58 %) of the patients had normal CTAs or showed CTA findings that were not relevant to the hemorrhage, clinical judgment should be exhausted before exposing them to radiation and intravenous contrast risks.

Digital Subtraction Angiography for CT Angiogram Negative Haemorrhages

BACKGROUND

In patients with subarachnoid haemorrhage (SAH) and a negative finding on CT angiography (CTA), further imaging with digital subtraction angiography (DSA) is commonly performed to identify the source of bleeding. The purpose of this study was to investigate whether negative findings on CTA can reliably exclude aneurysms in patients with acute SAH.

METHODS

This retrospective study identified all DSAs performed between August 2010 and July 2014 within our institution. CT angiography was performed with a 64-section multidetector row CT scanner. Only DSAs from patients with confirmed SAH and a negative CTA result were included in the final analyses. A fellowship-trained neuroradiologist reviewed the imaging results.

RESULTS

Of the 857 DSAs, 50 (5.83%) were performed in 35 patients with CTA-negative SAH. Of the 35 patients, three (8.57%) had positive findings on the DSA. In one patient, suspicious dissection of the extra- and intra-cranial segment of the right vertebral artery could not be confirmed even in retrospect. In the second patient, the suspicious finding of tiny protuberance from the left paraclinoid internal carotid artery (ICA) on DSA did not change on follow-up and did not change patient's management. The third patient had a posterior inferior cerebellar artery aneurysm, which was not seen on the initial CTA owing to the incomplete coverage of the head on the CTA.

CONCLUSION

In patients with SAH, negative findings on a technically sound CTA are reliable in ruling out aneurysms in any pattern of SAH or no blood on CT. Our observations need to be confirmed with larger prospective studies.

Intracerebral Hematoma Due to Aneurysm Rupture: Are There Risk Factors Beyond Aneurysm Location?

BACKGROUND

Along with subarachnoid hemorrhage (SAH), a ruptured aneurysm may also cause an intracerebral hematoma (ICH), which negatively impacts the functional outcome of SAH.

OBJECTIVE

To identify independent risk factors of aneurysmal ICH.

METHODS

Six hundred thirty-two consecutive patients with aneurysmal SAH treated at our institution from January 2005 to December 2012 were eligible for this study. Demographic parameters and preexisting comorbidities of patients, as well as various clinical and radiographic characteristics of SAH were correlated with the incidence and volume of aneurysmal ICH.

RESULTS

One hundred fifty-five patients (25%) had ICH on initial computed tomography with a mean volume of 26.7 mL (±26.8 mL). Occurrence and volume of ICH were associated with the location (distal anterior or middle cerebral artery >proximal anterior cerebral or internal carotid artery >posterior circulation, P < .001/P < .001) and size (>12 mm, P = .026/P < .001) of the ruptured aneurysm. Vascular risk factors independently increased the risk of ICH as well (arterial hypertension: odds ratio [OR] = 1.62, P = .032; diabetes mellitus: OR = 3.06, P = .009), while the use of aspirin (P = .037) correlated with the volume of ICH. The predictors of ICH were included into a risk score (0-9 points) that strongly predicted the occurrence of ICH (P = .01). Poor functional outcome after SAH was independently associated with the occurrence of ICH (P = .003, OR = 2.77) and its volume (P = .001, OR = 1.07 per-mL-increase).

CONCLUSION

Aneurysmal ICH is strongly associated with poorer functional outcome and seems to be predictable even before the bleeding event. The proposed risk factors for aneurysmal ICH require further validation and may be considered for treatment decisions regarding unruptured intracranial aneurysms.

ABBREVIATIONS

ACA, anterior cerebral arteryDHC, decompressive hemicraniectomyEVD, external ventricular drainageICA, internal carotid arteryICH, intracerebral hematomaMCA, middle cerebral arterymRS, modified Rankin scalePC, posterior circulationSAH, subarachnoid hemorrhageSIRS, systemic inflammatory response syndromeTCD, transcranial Doppler sonography.

Early identification of individuals at high risk for cerebral infarction after aneurysmal subarachnoid hemorrhage: the BEHAVIOR score

Cerebral infarction (CI) is a crucial complication of aneurysmal subarachnoid hemorrhage (SAH) associated with poor clinical outcome. We aimed at developing an early risk score for CI based on clinical characteristics available at the onset of SAH. Out of a database containing 632 consecutive patients with SAH admitted to our institution from January 2005 to December 2012, computed tomography (CT) scans up to day 42 after ictus were evaluated for CIs. Different parameters from admission up to aneurysm treatment were collected with subsequent construction of a risk score. Seven clinical characteristics were independently associated with CI and included in the Risk score (BEHAVIOR Score, 0 to 11 points): Blood on CT scan according to Fisher grade ⩾3 (1 point), Elderly patients (age ⩾55 years, 1 point), Hunt&Hess grade ⩾4 (1 point), Acute hydrocephalus requiring external liquor drainage (1 point), Vasospasm on initial angiogram (3 points), Intracranial pressure elevation >20 mm Hg (3 points), and treatment of multiple aneurysms ('Overtreatment', 1 point). The BEHAVIOR score showed high diagnostic accuracy with respect to the absolute risk for CI (area under curve=0.806, P<0.0001) and prediction of poor clinical outcome at discharge (P<0.0001) and after 6 months (P=0.0002). Further validation in other SAH cohorts is recommended.