Role of Indocyanine Green Videoangiography in Identification of Donor and Recipient Arteries in Cerebral Bypass Surgery.

The identification and preparation of a very good quality donor artery is a crucial step in every superficial temporal artery to middle cerebral artery (STA-MCA) bypass.For flow-preservation bypass performed for trapping of complex MCA aneurysms, the key element is the correct target of the recipient artery. When a cortical recipient artery (M4 segment of the MCA) is selected, this vessel must be a terminal branch of the artery whose sacrifice is necessary for definitive aneurysmal treatment.In this chapter we report on two techniques for (1) intraoperative mapping and preparation of good quality STA branch as the donor artery for STA-MCA bypass (mostly in the case the frontal branch of the STA needs to be used) and (2) selective identification of the correct superficial (M4 cortical) "recipient" artery in flow-preservation STA-MCA bypass performed for managing complex MCA aneurysms.Both techniques are based on the use of microscope-integrated indocyanine green videoangiography (ICG-VA), an intraoperative tool allowing observation and real-time assessment of blood flow in large and small vessels, with distinct evaluation of arterial, capillary, and venous phases.The two techniques contribute, respectively, to (1) reduce the risk of erroneous identification or injury of the donor artery in STA-MCA bypass procedures and (2) eliminate the risk of erroneous revascularization of a non-involved arterial territory in flow-preservation bypass surgery for managing complex MCA aneurysms.

Temporary Steno-occlusive Change in the Donor Artery During Mouth Opening (Big Bite Ischemic Phenomenon) After Superficial Temporal Artery to Middle Cerebral Artery Bypass in Adult Patients with Moyamoya Disease and Atherosclerosis.

BACKGROUND: Superficial temporal artery (STA) to middle cerebral artery (MCA) bypass is one of the most common surgical procedures performed for direct extracranial (EC) to intracranial (IC) bypasses. We describe a temporary steno-occlusive change in the STA that was caused by mouth opening after the STA-MCA bypass (so-called big bite ischemic phenomenon) in an adult patient with moyamoya disease. The aim of this study was to assess the incidence of this phenomenon in patients with atherosclerosis. METHODS: Adult patients with ischemic cerebrovascular disease who underwent STA-MCA anastomosis were included in this study. Ultrasound examinations were postoperatively performed on 62 sides to determine whether mouth opening affected the blood flow of the donor STA and resulted in any ischemic symptoms within 1 min. Computed tomography angiography was performed during both mouth opening and closing when blood flow changes were recognized in the donor STA. RESULTS: During wide mouth opening, steno-occlusion of the donor STA occurred in 8 of the 62 affected sides (12.9 %), which included 3 of the 47 sides (6.4 %) in patients with atherosclerosis and 5 of the 15 sides (33.3 %) in patients with moyamoya disease. CONCLUSION: Steno-occlusion of the donor STA occurred during wide mouth opening in 12.9 % of the sides of adult patients who had undergone STA-MCA anastomosis. This phenomenon was more common in patients with moyamoya disease than in patients with atherosclerosis.

Indocyanine green videoangiography for the identification of superficial temporal artery branches in EC-IC bypass surgery.

BACKGROUND: Superficial temporal artery-to-middle cerebral artery (STA-MCA) bypass remains an essential tool for managing complex cerebrovascular conditions. A crucial surgical step is the identification and safe dissection of the bypass donor artery. If the frontal branch of the STA is used, a curvilinear fronto-temporal scalp flap generally allows for a clean dissection from the underside of the scalp flap. This dissection is sometimes tedious, since the frontal branch is not always easily visible and due to variability of its anatomy. With this article, we report on the feasibility and effectiveness of a simple indocyanine green videoangiography (ICG-VA)-assisted technique for the identification of the STA branches from the underside of a fronto-temporal scalp flap in bypass surgery. METHODS: The technique is based on the analysis of the difference in timing of filling of scalp vessels illuminated via ICG-VA from the underside of a scalp flap. Three illustrative cases are reported. RESULTS: ICG-VA permitted the correct identification and safe dissection of the donor vessels (STA branches) in all three patients. There were no complications due to the ICG-VA. CONCLUSIONS: This technique allows reliable visualization of the STA and its branches at once before microsurgical dissection. The information provided by ICG-VA enables precise mapping and preparation of the STA. The simplicity and safety of this technique make it an effective tool for intraoperative identification of the STA and its branches.

The effect of single or multiple arteries in the donor kidney on renal transplant surgical outcomes.

BACKGROUND: As the number of end-stage renal disease (ESRD) patients is increasing, but there are not enough living donors, it is necessary to broaden the criteria for candidates who can undergo donor nephrectomy. Thanks to surgeons' increasing experience with laparoscopic donor nephrectomy (LND), multiple renal artery grafts, previously considered a relative contraindication to donor nephrectomy, have become candidates for LDN. We aimed to compare the outcomes of donors and recipients with single artery and with multiple arteries in LDN. METHODS: A total of 214 patients were included in the study. Patients were divided into two groups according to the number of donor arteries: donors with one artery (group 1) and donors with multiple arteries (group 2). The number of donor arteries, operative time, warm ischemia time (WIT), cold ischemia time (CIT), arterial anastomosis time, venous anastomosis time, the extent of bleeding, and preoperative complications were recorded to evaluate the preoperative data. RESULTS: The mean operation time in group 1 was 90.3 ± 11.8 min, while in group 2, it was 102.1 ± 5.5 min (p = 0.000). WIT group 1 was 90.9 ± 4.3 s and group 2 100.6 ± 2.1 s (p = 0.000). Arterial anastomosis time was 12.25 ± 3.8 in group 1 and 22.5 ± 4.5 in group 2 (p = 0.000). No statistically significant difference was found between the two groups in other parameters. CONLUSION: Increasing the number of donor arteries in renal transplantation (RT) operations prolonged the operation time on both the donor and recipient sides. Still, it had no negative impact on complications or graft function in the postoperative period.

Automatic assessment of collaterals physiology in chronic total occlusions by means of artificial intelligence.

BACKGROUND: Assessment of collaterals physiology in chronic total occlusions (CTO) currently requires dedicated devices, adds complexity, and increases the cost of the intervention. This study sought to derive collaterals physiology from flow velocity changes (ΔV) in donor arteries, calculated with artificial intelligence- aided angiography. METHODS: Angiographies with successful percutaneous coronary intervention (PCI) in 2 centers were retro- spectively analyzed. CTO collaterals were angiographically evaluated according to Rentrop and collateral connections (CC) classifications. Flow velocities in the primary and secondary collateral donor arteries (PCDA, SCDA) were automatically computed pre and post PCI, based on a novel deep-learning model to extract the length/time curve of the coronary filling in angiography. Parameters of collaterals physiology, Δcollateral-flow (Δfcoll) and Δcollateral-flow-index (ΔCFI), were derived from the ΔV pre-post. RESULTS: The analysis was feasible in 105 out of 130 patients. Flow velocity in the PCDA significantly decreased after CTO-PCI, proportionally to the angiographic collateral grading (Rentrop 1: 0.02 ± 0.01 m/s; Rentrop 2: 0.04 ± 0.01 m/s; Rentrop 3: 0.07 ± 0.02 m/s; p < 0.001; CC0: 0.01 ± 0.01 m/s; CC1: 0.04 ± ± 0.02 m/s; CC2: 0.06 ± 0.02 m/s; p < 0.001). Δfcoll and ΔCFI paralleled ΔV. SCDA also showed a greater reduction in flow velocity if its collateral channels were CC1 vs. CC0 (0.03 ± 0.01 vs. 0.01 ± 0.01 m/s; p < 0.001). For each individual patient, ΔV was more pronounced in the PCDA than in the SCDA. CONCLUSIONS: Automatic assessment of collaterals physiology in CTO is feasible, based on a deeplearning model analyzing the filling of the donor vessels in angiography. The changes in collateral flow with this novel method are quantitatively proportional to the angiographic grading of the collaterals.

Bipolar Cutting Method: Another Technique for Harvesting Donor Artery With Histological Investigation.

BACKGROUND: Safe and appropriate harvesting of the donor scalp vessel is the first key procedure in any type of bypass surgery. OBJECTIVE: To use the so-called bipolar cutting method to harvest donor arteries, in which the donor arteries are skeletonized with bipolar cautery. The surgical procedure and the preparation of the equipment of the bipolar cutting method are described. The surgical results and histological assessment are presented. METHODS: The bipolar generator was set at 50 Malis units in the coagulation mode. Under the surgical microscope, the surrounding tissue of the donor artery was divided and coagulated with the bipolar forceps. The donor artery was completely skeletonized to provide adequate length. After the recipient artery was chosen and the anastomosis site was decided, the distal end of the donor artery was cut to the appropriate length. The remnant fragment of the donor artery was histologically investigated for any damage to the arterial wall. The specimen was cut longitudinally to observe the entire length of the arterial wall and stained with hematoxylin and eosin and elastica van Gieson. RESULTS: A total of 30 bypass surgeries were performed and 38 histological specimens were obtained between February 2015 and June 2016. The success rate of the bypass was 96%. No arterial wall damage such as thermal injury or dissection of the wall was recognized in any of the specimens. CONCLUSION: The bipolar cutting method is a useful and safe method for harvesting donor scalp artery.

Impact of the origin of the collateral feeding donor artery on short-term mortality in ST-elevation myocardial infarction with comorbid chronic total occlusion.

BACKGROUND: Patients with ST-elevation myocardial infarction (STEMI) and multi-vessel disease (MVD) have higher mortality, especially with comorbid chronic total occlusion (CTO). The origin of collateral flow to the CTO segment has not been studied in regard to short-term mortality. This study examined the impact of collateral feeding donor arteries from an infarct-related artery (IRA) or non-IRA to the comorbid CTO segment in regard to STEMI short-term mortality. METHODS: Data from 760 consecutive STEMI patients who underwent primary percutaneous coronary intervention were obtained retrospectively from medical records. The number of vessels involved and origin of the collateral feeding donor artery were evaluated using angiograms from the primary percutaneous coronary intervention. The study population was divided into patients with: single-vessel disease (SVD) (n=483), MVD without CTO (n=208), and MVD with CTO (n=64). All CTO segments had collateral flow from an IRA (n=23) or non-IRA (n=46). All-cause mortality (30-day) was analyzed. RESULTS: Compared to SVD and MVD without CTO, MVD with comorbid CTO had a higher mortality (5.4% vs. 15.9% vs. 24.6%, P<0.0001, respectively). Of patients with CTO, those with collateral flow from the IRA had significantly higher mortality than the non-IRA group (52.2% vs. 10.9%, P<0.0001). Collateral flow from the IRA was extracted as an independent predictor associated with 30-day all-cause mortality using a multivariate Cox proportional hazards model (hazard ratio 4.71, 95% confidence interval 1.60-14.2, P=0.0005). CONCLUSIONS: The origin of the collateral donor artery from the IRA had an impact on short-term mortality in STEMI patients with comorbid CTO lesions.