Article Figures & Data
Figures
- Fig 1.
A 77-year-old woman with a ruptured right middle cerebral artery aneurysm who was admitted 5 days after onset. T1WI on admission shows BHSB in the bilateral Sylvian fissure (A, arrows) that matches the blood distribution on the FLAIR image (B, arrows). These findings are typical of subacute SAH with T1-FLAIR-matched SAH that was not associated with rebleeding. Reprinted with permission from Shimoda M. Neuroimaging for headache. Journal of Clinical and Experimental Medicine (IGAKU NO AYUMI) 2012;243:1086–94; Ishiyaku Publishers, Inc.
- Fig 2.
Typical neuroradiologic findings in a patient with minor leak before major SAH attack. Images are from an 80-year-old woman with a ruptured right middle cerebral artery aneurysm. T1WI on admission shows clearly iso- to mildly hyperintense blood obscuring the right Sylvian fissure, in addition to the more conspicuous bright T1 foci (A and B, circles). These findings indicate subacute subarachnoid blood due to a minor leak that occurred before the major attack. FLAIR images on admission show the SAH in the acute phase in the quadrigeminal cistern and left Sylvian fissure (C and D, circles), in addition to the BHSB on T1WI. We defined this as T1-FLAIR mismatch and used it as a neuroradiologic diagnosis of minor leak that occurred before major SAH.
- Fig 3.
Typical neuroradiologic findings in a case with minor leak before a major SAH attack with intra-Sylvian hematoma. Images are from a 66-year-old woman with a ruptured right middle cerebral artery aneurysm. T1WI shows iso- to mildly hyperintense blood obscuring the right Sylvian fissure and suprasellar cistern, in addition to the more conspicuous bright T1 foci including the neighboring area of the ruptured aneurysm. An intra-Sylvian hematoma is depicted as an isointense signal (A circle, B). FLAIR images show the intra-Sylvian hematoma and SAH (right Sylvian fissure, suprasellar and right ambient cistern) as a high-intensity signal, which indicates acute blood (C and D, circles).
Tables
Total T1-FLAIR Mismatch P Value Positive Negative No. of patients 127 43 (33.9) 84 (66.1) Warning sign Positive 14 13 (30.2) 1 (1.2) <.001 Negative 54 2 (4.7) 52 (61.9) Unknown 59 28 (65.1) 31 (36.9) Mean age (yr) 61.5 ± 14.2 66.5 ± 13.2 58.9 ± 14.0 .004 Age range (yr) 21–89 40–85 21–89 Elderly patients Older than 80 years 12 10 (23.3) 2 (2.4) <.001 Female sex 89 32 (74.4) 57 (67.9) .541 Rebleeding after admission 28 19 (44.2) 9 (1.7) <.001 WFNS grade on admission Grades I–II 97 28 (65.1) 69 (82.1) .028 Grades IV–V 28 13 (30.2) 15 (17.9) .120 Fisher group Group 3 85 30 (69.8) 55 (65.5) .550 Intracerebral hemorrhage 25 19 (44.2) 6 (7.1) <.001 Acute hydrocephalus 61 26 (60.5) 35 (41.7) .060 Aneurysm site Anterior communicating artery 41 9 (20.9) 32 (38.1) Anterior cerebral artery 8 4 (9.3) 4 (4.8) Internal carotid artery 38 12 (27.9) 26 (31.0) Middle cerebral artery 31 17 (39.5) 14 (16.7) Posterior circulation 8 0 8 (9.5) .051 Aneurysm size >5 mm 75 31 (72.1) 44 (52.4) .037 >10 mm 8 3 (7.0) 5 (6.0) 1.000 Note:—WFNS indicates World Federation of Neurological Surgeons.
↵a Values are No. (%) unless otherwise stated. The “No. of patients” row shows the percentage of the total number of patients, whereas all other percentages in the “Positive” and “Negative” columns are the percentages of patients with positive and negative findings, respectively.
Total T1-FLAIR Mismatch P Value Positive Negative No. of patients 127 43 (33.9) 84 (66.1) Aneurysm operation Craniotomy 105 36 (83.7) 69 (82.1) 1.000 Coiling 22 7 (16.3) 15 (17.9) Delayed angiographic vasospasm 35 19 (44.2) 16 (19.0) .003 DIND 22 16 (37.2) 6 (7.1) <.001 Infarction due to delayed vasospasm on DWI 30 17 (39.5) 13 (15.5) .003 Chronic hydrocephalusb 54 23 (62.2) 31 (37.8) .029 mRS score at 3 months >3–6 41 28 (65.1) 13 (15.5) <.001 Note:—DIND indicates delayed ischemic neurologic deficits.
↵a The “No. of patients” row shows the percentage of the total number of patients, whereas all other percentages in the “Positive” and “Negative” columns are the percentages of patients with positive and negative findings, respectively.
↵b The incidence of chronic hydrocephalus was calculated for the surviving patients.
- Table 3:
Results of multivariate logistic regression analysis for the presence of a minor leak before admission diagnosed by T1-FLAIR mismatch
Odds Ratio 95% CI P Value Preoperative clinical factors Age older than 80 years 8.475 1.639–43.478 .011 Rebleeding 5.291 2.028–13.889 .001 Associated neuroradiologic findings on admission Intracerebral hemorrhage on CT 7.197 2.457–20.833 <.001 Postoperative factors mRS score 3–6 6.690 2.548–17.564 <.001
