Article Figures & Data
Figures
- Fig 1.
Illustration of the Modified Raymond-Roy classification and additional definitions of the type of recanalization used in the present study. Class I: complete obliteration; class II: residual neck; class IIIa: residual aneurysm with contrast within the coil interstices; class IIIb: residual aneurysm with contrast along the aneurysm wall. The appearance of new blebs was distinguished from an increase in the diameter of the coiled aneurysm. Except for the appearance of new blebs, an increase in the diameter of the coiled aneurysm was termed “aneurysm growth.”
- Fig 2.
DSA findings for ruptured recanalized aneurysms in the unruptured group. Case 1-pre: preprocedural basilar artery–bifurcation aneurysm; case 1-post: class II aneurysm occlusion immediately after the procedure; case 1–6m: class IIIb recanalization at 6 months after the procedure; case 1–8m: ruptured recanalized aneurysm at 8 months after the procedure; case 2-pre: preprocedural ICA–posterior communicating artery aneurysm; case 2-post: class IIIb aneurysm occlusion immediately after the procedure; case 2–6m: progression of the class IIIb recanalization at 6 months after the procedure; case 2–76m: ruptured recanalized aneurysm with a new bleb at 76 months after the procedure; case 3-pre: preprocedural paraclinoid-ICA aneurysm; case 3-post: class IIIb aneurysm occlusion immediately after the procedure; case 3–2m: ruptured recanalized aneurysm with a new bleb at 2 months after the procedure; case 4-pre: preprocedural basilar artery–bifurcation aneurysm; case 4-post: class IIIb aneurysm occlusion immediately after the procedure; case 4–6m: no change at 6 months after the procedure; case 4–24m: MRA shows the ruptured recanalized aneurysm with a new bleb at 24 months after the procedure.
- Fig 3.
DSA findings for ruptured recanalized aneurysms in the ruptured group. Case 1-pre: preprocedural anterior communicating artery aneurysm; case 1-post: class II aneurysm occlusion immediately after the procedure; case 1–1w: class IIIb recanalization at 1 week after the procedure; case 1–1m: ruptured recanalized aneurysm with a new bleb at 1 month after the procedure; case 2-pre: preprocedural anterior communicating artery aneurysm; case 2-post: class II aneurysm occlusion immediately after the procedure; case 2–1w: class IIIb recanalization at 1 week after the procedure; case 2–1m: ruptured recanalized aneurysm with a new bleb at 1 month after the procedure; case 3-pre: preprocedural ICA–posterior communicating artery aneurysm; case 3-post: class IIIb aneurysm occlusion immediately after the procedure; case 3–6m: progression of the class IIIb recanalization at 6 months after the procedure; case 3–29m: ruptured recanalized aneurysm at 29 months after the procedure; case 4-pre: preprocedural ICA–posterior communicating artery aneurysm; case 4-post: class IIIb aneurysm occlusion immediately after the procedure; case 4–6m: progression of the class IIIb recanalization at 6 months after the procedure; case 4–7m: ruptured recanalized aneurysm at 7 months after the procedure.
Tables
- Table 1:
Patient and aneurysm characteristics, volume embolization ratio, use of stents, and follow-up terma
Unruptured Group Ruptured Group All Aneurysms (n = 426) Recanalized Aneurysms (n = 38) All Aneurysms (n = 169) Recanalized Aneurysms (n = 37) Patient characteristic Age (yr) 63.0 (52.0–70.0) 65.0 (49.8–71.3) 66.0 (52.0–77.5) 59.0 (44.5–76.5) Male sex 105 (24.6%) 6 (15.8%) 56 (33.1%) 10 (27.0%) Aneurysm location ICA-cavernous 12 (2.8%) 2 (5.3%) 0 (0.0%) 0 (0.0%) ICA-paraclinoid 188 (44.1%) 9 (23.7%) 5 (3.0%) 2 (5.4%) ICA-PcomA 49 (11.5%) 9 (23.7%) 55 (32.5%) 16 (43.2%) ICA-AchoA 10 (2.3%) 0 (0.0%) 13 (7.7%) 4 (10.8%) ICA-bifurcation 11 (2.6%) 2 (5.3%) 3 (1.8%) 0 (0.0%) MCA 6 (1.4%) 0 (0.0%) 4 (2.4%) 0 (0.0%) AcomA 66 (15.5%) 1 (2.6%) 57 (33.7%) 11 (29.7%) VA 15 (3.5%) 4 (10.5%) 8 (4.7%) 1 (2.7%) BA-SCA 16 (3.8%) 2 (5.3%) 2 (1.2%) 1 (2.7%) BA-bifurcation 41 (9.6%) 9 (23.7%) 12 (7.1%) 2 (5.4%) Others 12 (2.8%) 0 (0.0%) 10 (5.9%) 0 (0.0%) Aneurysm size Dome 6.2 (4.9–8.4) 10.1 (7.0–14.1) 6.5 (5.0–9.3) 7.7 (5.4–13.0) Neck 3.8 (2.9–5.1) 5.9 (4.7–7.7) 3.2 (2.4–4.2) 4.0 (2.7–5.9) Endovascular procedures VER 26.9 (21.9–32.8) 23.0 (18.0–29.2) 25.8 (19.8–33.2) 23.7 (18.9–29.5) Without stent 240 (56.3%) 19 (50.0%) 169 (100.0%) 37 (100.0%) With stent 186 (43.7%) 19 (50.0%) 0 (0.0%) 0 (0.0%) Follow-up Duration (mo) 58.5 (24.0–86.0) 74.0 (30.5–96.3) 18.0 (3.0–48.0) 28.0 (10.0–56.0) Note:—AchoA indicates anterior choroidal artery; VA, vertebral artery; BA, basilar artery; SCA, superior cerebellar artery; VER, volume embolization ratio.
↵a Unruptured group indicates unruptured aneurysms that underwent coil embolization; ruptured group, ruptured aneurysms that underwent coil embolization. Data are Unruptured Group (n = 426): Recanalization after coil embolization occurred in 38 of 426 unruptured aneurysms. Ruptured Group (n = 169): Recanalization after coil embolization occurred in 37 of 169 ruptured aneurysms.
Unruptured Groupa Ruptured Groupa Type of recanalization on final DSA Class II 3 (7.9%) 7 (18.9%) Class IIIa 12 (31.6%) 7 (18.9%) Class IIIb 23 (60.5%) 23 (62.2%) Aneurysm growth 12 (31.6%) 3 (8.1%) Appearance of bleb 2 (5.3%) 1 (2.7%) Retreatment 18 (47.4%) 16 (43.2%) Rupture 4 (10.5%) 4 (10.8%) Rupture risk (/aneurysm) 0.94% 2.37% Rupture risk (/yr) 0.20% 0.97% Final mRS score without ruptured recanalized aneurysmb 0–2 31 (91.2%) 21/33 (63.6%) 3–4 1 (2.9%) 6/33 (18.2%) 5–6 2 (5.9%) 6/33 (18.2%) Final mRS score with ruptured recanalized aneurysmc 0–2 2 (50.0%) 1 (25.0%) 3–4 0 (0.0%) 2 (50.0%) 5–6 2 (50.0%) 1 (25.0%) - Table 3:
Type of aneurysm occlusion and recanalization on follow-up DSA, the timing of retreatment and rupture, and the type of recanalization immediately before retreatment and rupture in the unruptured groupa
Initial (n = 38) (n = 38) 6 Months (n = 36) (n = 38) 1 Year (n = 16) (n = 37) 2 Years (n = 3) (n = 35) 3 Years (n = 0) (n = 26) 4 Years (n = 0) (n = 26) 5 Years (n = 1) (n = 23) 6 Years (n = 1) (n = 22) 7 Years (n = 0) (n = 16) 8 Years (n = 1) (n = 13) Type of aneurysm occlusion and recanalization I 5 2 0 0 0 0 0 0 0 0 II 10 4 1 0 0 0 0 0 0 0 IIIa 12 13 9 1 0 0 0 1 0 0 IIIb 11 17 6 2 0 0 1 0 0 1 Type of recanalization of retreated recanalized aneurysms IIIa 0 1 3 0 0 0 0 1 0 0 IIIb 0 8 2 1 0 0 1 0 0 1 Type of recanalization of ruptured recanalized aneurysms IIIa 0 0 0 0 0 0 0 0 0 0 IIIb 1 1 1 0 0 0 0 1 0 0 ↵a The first row of numbers in parentheses indicates the number of cases that underwent follow-up DSA at that time; the second row of numbers in parentheses, the number of cases that underwent follow-up MRA at that time.
- Table 4:
Type of aneurysm occlusion and recanalization on follow-up DSA, the timing of retreatment and rupture, and the type of recanalization immediately before retreatment and rupture in the ruptured groupa
Initial (n = 37) (n = 37) 1 Week (n = 37) (n = 37) 1 Month (n = 34) (n = 37) 6 Months (n = 19) (n = 29) 1 Year (n = 12) (n = 28) 2 Years (n = 0) (n = 22) 3 Years (n = 0) (n = 18) 4 Years (n = 0) (n = 13) 5 Years (n = 0) (n = 9) 6 Years (n = 0) (n = 6) Type of aneurysm occlusion and recanalization I 14 9 3 0 0 0 0 0 0 0 II 17 19 13 5 2 0 0 0 0 0 IIIa 2 2 3 5 3 0 0 0 0 0 IIIb 4 7 15 9 7 0 0 0 0 0 Type of recanalization of retreated recanalized aneurysms IIIa 0 0 0 2 1 0 0 0 0 0 IIIb 0 0 11 1 1 0 0 0 0 0 Type of recanalization of ruptured recanalized aneurysms IIIa – – 0 0 0 0 0 0 0 0 IIIb – – 2 1 0 1 0 0 0 0 Note:— – indicates not available.
↵a Aneurysms that reruptured in the acute phase (<1 month after the initial rupture) were excluded. The first-row of number in parentheses indicates the number of cases that underwent follow-up DSA at that time. The second-row of number in parentheses indicates the number of cases that underwent follow-up MRA at that time.
- Table 5:
Factors associated with rupture after coil embolization in untreated recanalized aneurysms in the unruptured groupa
Untreated Recanalized Aneurysms (n = 20) Unruptured (n = 16) Ruptured (n = 4) P Value Age (yr) 67.0 (60.3–72.8) 63.0 (55.8–70.3) .570 Sex Male 1 (6.3%) 1 (25.0%) .264 Female 15 (93.7%) 3 (75.0%) Location ICA 5 (31.2%) 1 (25.0%) .937 ICA-PcomA 4 (25.0%) 1 (25.0%) AcomA 1 (6.3%) 0 (0.0%) Posterior 6 (37.5%) 2 (50.0%) Dome 9.2 (7.6–13.4) 9.9 (6.6–11.1) .813 Neck 5.5 (4.4–7.0) 4.5 (3.2–8.8) .741 VER 22.1 (13.9–26.1) 25.1 (18.5–37.3) .321 Use of stent No 9 (56.3%) 2 (50.0%) .822 Yes 7 (43.7%) 2 (50.0%) Type of recanalization on final DSA II + IIIa 10 (62.5%) 0 (0.0%) .025b IIIb 6 (37.5%) 4 (100.0%) Aneurysm growth No 13 (81.3%) 3 (75.0%) .780 Yes 3 (18.7%) 1 (25.0%) Note:—ICA indicates ICA other than ICA-PcomA; VA, vertebral artery; BA, basilar artery; SCA, superior cerebellar artery; VER, volume embolization ratio; Posterior, posterior circulation including the VA, BA-SCA, and BA-bifurcation.
↵a Data are recanalized aneurysms in the unruptured group (n = 38): Twenty of 38 recanalized aneurysms were untreated. Among 20 untreated recanalized aneurysms, 16 aneurysms unruptured and 4 aneurysms ruptured.
↵b Statistical significance.
- Table 6:
Factors associated with rupture after coil embolization in untreated recanalized aneurysms in the ruptured groupa
Untreated Recanalized Aneurysms (n = 21) Unruptured (n = 17) Ruptured (n = 4) P Value Age (yr) 62.0 (44.5–78.0) 55.5 (47.5–75.5) .929 Sex Male 6 (35.3%) 1 (25.0%) .694 Female 11 (64.7%) 3 (75.0%) Location ICA 3 (17.7%) 0 (0.0%) .628 ICA-PcomA 9 (52.9%) 2 (50.0%) AcomA 4 (23.5%) 2 (50.0%) Posterior 1 (5.9%) 0 (0.0%) Dome 6.2 (5.2–8.7) 9.4 (5.3–14.4) .347 Neck 3.2 (2.5–4.6) 5.2 (3.6–9.1) .066 VER 24.9 (21.3–29.5) 25.5 (16.7–28.5) .741 Use of stent No 17 (100.0%) 4 (100.0%) – Yes 0 (0.0%) 0 (0.0%) Type of recanalization on final DSA II+IIIa 11 (64.7%) 0 (0.0%) .020b IIIb 6 (35.3%) 4 (100.0%) Aneurysm growth No 16 (94.1%) 4 (100.0%) .619 Yes 1 (5.9%) 0 (0.0%)
