Fig 1.
Intra-operative conventional digital subtraction angiography (cDSA) (A, C–F) and cone-beam computed tomography (B) images illustrating the procedure of urinary bladder embolization in a rabbit model.
(A) Aortic angiogram depicting the right common (Rt. CIA), external (EIA), and internal (IIA) iliac arteries. (B) Three-dimensional volume rendering technique image: the umbilical artery (UA) originates from the ventromedial aspect of the CIA. (C) Roadmap image: advancing the microcatheter and microwire into the UA. (D) Umbilical angiogram revealing the cranial vesical artery (CVA) and deferential artery (DA) branches. The ventral branch of the DA (VB) courses caudally toward the testis. (E, F) Angiograms at the level of the CIA pre- (E) and post-embolization (F), respectively. The post-embolization image demonstrates an absence of blood flow through the UA to the urinary bladder.
Fig 2.
Experiment schedule for embolization, angiography, and euthanization.
Table 1.
Angiographic findings scoring.
Table 2.
Histopathologic findings scoring.
Table 3.
Hematological and serum biochemical parameters of the rabbits on day 0 and euthanization days.
Table 4.
Angiographic scoring analysis.
Fig 3.
Representative angiographic images at day 0 (A, pre-embolization), 3 days post-embolization (DPE) (B), 7 DPE (C), and 14 DPE (D).
(A) The cranial vesical artery (CVA) and normal microvasculature supplying the bladder wall are clearly visualized with normal urinary bladder (UB) blush (blue dotted line). (B) 3 DPE: recanalization of the cranial vesical artery is observed; however, the microvascularization of the bladder wall is reduced compared with that on day 0. (C) 7 DPE: the bladder lumen appears collapsed, and marked enlargement of the cranial vesical artery with distinct hypervascularization of the bladder wall is visible. (D) 14 DPE: the degree of hypervascularization is mildly reduced compared with 7 DPE.
Fig 4.
In-situ images of the urinary bladder at necropsy from all rabbits at each time-point. (A – C) Day 0: No gross abnormal lesion in the urinary bladder. (D -F) DPE 3: Cranial vesical artery and vein are dilated (white arrows) with reddish moderate to severe erythema of the urinary bladder wall. (G – I) DPE 7: Cranial vesical vessels are distinctly enlarged, and the bladder wall is thickened and collapsed. (G and I, yellow arrow heads) Focal yellow necrotic lesions. (J – L) DPE 14: Cranial vesical vessels remain dilated (black arrows); however, the bladder wall exhibits recovery with mild erythema.
Table 5.
Semi-quantitative scoring analysis of histopathologic findings.
Fig 5.
Representative images of tissue sections at various time-points post-embolization.
(A) Tissue collected immediately post-embolization (day 0). Injected embolic materials (blank arrowheads) are noted. Bar = 200 µm (B) Tissue collected 3 DPE. Transitional cell degeneration and desquamation (arrow), necrosis of submucosa (arrowhead), and lymphoid cell infiltration (asterisk) are noted. Bar = 400 µm (C) Tissue collected 7 DPE. Regenerated transitional cells (red arrow), lymphoid cell infiltration (asterisk) and neovascularization (red arrowheads) are noted. Bar = 400 µm (D) Tissue collected 14 DPE. Transitional cells are fully regenerated with neovascularization (red arrowheads). Bar = 300 µm. These samples illustrate the temporal progression of histopathological changes post-embolization.