Diagnostic yield of computed tomography angiography and magnetic resonance angiography in patients with catheter angiography-negative subarachnoid hemorrhage.
OBJECTIVE
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.
Division of Neuroradiology, Mallinckrodt Institute of Radiology, Washington University Schoolof Medicine, Saint Louis, Missouri, USA. josser.delgado@crlmed.com
Josser E
JE
Delgado Almandoz
Bharathi D
BD
Jagadeesan
Daniel
D
Refai
Christopher J
CJ
Moran
DeWitte T
DT
Cross
Michael R
MR
Chicoine
Keith M
KM
Rich
Michael N
MN
Diringer
Ralph G
RG
Dacey
Colin P
CP
Derdeyn
Gregory J
GJ
Zipfel
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002404:Catheterization / Q000379:methods*; D002533:Cerebral Angiography / Q000379:methods*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000175:diagnosis; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008636:Mesencephalon; D008875:Middle Aged; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013345:Subarachnoid Hemorrhage / Q000175:diagnosis*; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult