TABLE 1:

Patient characteristics, angiographic findings, and results of acetazolamide-challenged single photon emission CT

Patient Characteristics				Angiographic Findings					ACZ-Challenged SPECT
Patient Characteristics				Occlusive		Maximum rACCT (s)	rACCT (s)	rACCT Ratio	ACZ-Challenged SPECT
Patient No.	Sex	Age (yr)	Diagnosis	Artery	Grade (%)	Occlusive Side [Flow Pattern]	Normal Side	rACCT Ratio	Qualitative Estimation	Baseline AI	ACZ AI	rRI
1	M	61	TIA	R MCA	80	5.9 [lept(A)]	2.9	2.03	Poor	1.03	0.90	0.87
2	F	65	TIA	R MCA	99	5.4 [lept(P)]	2.6	2.08	Poor	1.01	0.89	0.88
3	M	55	ATI	R ICA	Occlusion	3.4 [lept(P)]	2.5	1.36	Normal	1.00	0.96	0.96
4	M	68	ATI	R ICA	Occlusion	2.6 [Willis]	2.6	1.00	Normal	1.05	1.08	1.03
5	M	74	ATI	R ICA	99	7.9 [physiol]	4.2	1.88	Poor	0.86	0.65	0.76
6	M	75	TIA	R MCA	Occlusion	4.9 [lept(A)]	4.7	1.04	Normal	1.03	1.01	0.98
7	M	72	TIA	R ICA	Occlusion	3.5 [lept(P)]	3.0	1.17	Normal	0.95	0.95	1.00
8	M	63	ATI	R ICA	Occlusion	8.8 [lept(P)]	3.9	2.26	Poor	0.78	0.55	0.71
9	M	70	TIA	R ICA	70	3.7 [physiol]	3.1	1.19	Normal	0.96	0.98	1.02
10	M	73	Lacuna	L MCA	70	3.9 [physiol]	3.4	1.15	Normal	0.93	0.95	1.02
11	M	71	ATI	R ICA	99	5.7 [lept(P)]	2.4	2.38	Poor	0.69	0.52	0.75
12	F	70	ATI	L ICA	70	6.8 [physiol]	3.4	2.00	Poor	0.97	0.87	0.90
13	M	71	ATI	L MCA	Occlusion	7.3 [lept(P)]	3.2	2.28	Poor	1.00	0.89	0.89
14	M	62	ATI	R MCA	70	2.5 [physiol]	2.4	1.04	Normal	0.95	1.00	1.05
15	M	65	Lacuna	L ICA	75	5.1 [physiol]	3.5	1.46	Poor	0.88	0.83	0.94
16	M	64	TIA	R ICA	80	3.2 [Willis]	2.7	1.19	Normal	1.02	1.00	0.98
17	M	47	TIA	L MCA	Occlusion	4.7 [lept(A)]	2.1	2.24	Poor	0.91	0.79	0.87
18	M	60	TIA	R ICA	99	6.3 [physiol]	3.7	1.70	Poor	0.86	0.77	0.9
19	M	53	TIA	R ICA	Occlusion	5.8 [lept(A)]	3.0	1.93	Poor	0.89	0.80	0.90
20	M	83	TIA	L ICA	80	5.9 [lept(A)]	3.1	1.90	Poor	0.97	0.80	0.82
21	F	71	TIA	R ICA	100	5.7 [lept(P)]	3.5	1.63	Poor	1.03	0.76	0.74
22	M	52	TIA	R MCA	100	7.0 [lept(P)]	2.7	2.59	Poor	0.96	0.67	0.70
23	M	79	TIA	R ICA	70	5.3 [lept(P)]	3.7	1.43	Normal	1.04	0.97	0.93
24	M	69	TIA	R ICA	90	6.8 [lept(P)]	3.5	1.94	Poor	0.99	0.88	0.89
25	F	67	TIA	R ICA	100	4.7 [lept(P)]	2.6	1.81	Poor	1.02	0.87	0.85
26	M	77	ATI	R ICA	100	6.7 [EC-IC]	3.2	2.09	Poor	0.94	0.75	0.80
27	M	69	TIA	L ICA	100	6.7 [Willis]	4.3	1.56	Poor	0.93	0.80	0.86
28	M	68	Lacuna	R ICA	70	3.3 [physiol]	2.7	1.22	Normal	1.04	1.03	0.99

Note.—ACZ indicates acetazolamide; SPECT, single photon emission CT; rACCT, regional arteriocapillary circulation time; AI, asymmetry index; rRI, regional reactivity index; M, male; F, female; TIA, transient ischemic attack; ATI, atherothrombotic infarction; Lacuna, lacuna infarction; R, right; L, left; MCA, middle cerebral artery; ICA, internal carotid artery; lept(A), leptomeningeal collateral via anterior cerebral artery; lept(P), leptomeningeal collateral via posterior cerebral artery; Willis, circle of Willis collateral; physiol, physiological flow pattern; EC-IC, external to internal carotid collateral.