The aim of this study was to prove the hypothesis that intraoperative fluorescence-angiography
using indocyanine-green (ICGFA) can be used to predict the occurrence of perfusion-associated
complications following microvascular reconstruction. Consecutively perioperative
data of patients who received microvascular reconstruction of the head and neck region
and underwent ICGFA immediately after anastomosis was established were analyzed. The
flow parameters analyzed in the investigation were (1) the baseline (Int(max)) and
(2) peak intensity (Int(m)(ax)) of fluorescence, (3) the quotient of the two aforementioned
parameters (F-max/min) as an expression of the relative total increase, (4) the absolute
difference in the two parameters (Diff(int)) in terms of amplitude, (5) the duration
of the intensity increase (T-R(ise)) until the peak, and (6) the percent intensity
increase per second (Rise/sec(rel)). Within the first 2 weeks postoperatively, every
flap complication was documented. Subsequently, statistical analysis of the flap outcome
was performed based on the flow parameters obtained intraoperatively. Data of 67 patients
(male/female: 41/26) with an average age of 64 years (range 29-84 years) were analyzed.
In 10 of these patients, postoperative perfusion-associated complications were observed
(arterial/venous/microcirculatory: 4/3/3; p = 0.12). The analysis of the intraoperatively
obtained flow parameters showed a significant difference in the ratio of maximum and
minimum intensity in arterial pedicle perfusion (F-max/min) of patients with and without
complications (with vs. without complications: 2.3 +/- 1.0 vs. 5.0 +/- 4.9; p < 0.01)
and strong correlation of the mentioned parameter with the occurrence of perfusion-associated
complications (odds ratio = 0.27; p = 0.01). The ratio of maximum and minimum intensity
(F-max/min) is a predictor for postoperative venous stasis, arterial hypoperfusion
and impaired microcirculation of a microvascular flap. Anastomoses with F-max/min
<2.85 should be revised. However, a high technique sensitivity has to be considered,
due to which sufficient hemostasis and reduction of motion artefacts have to be taken
into account in order to obtain useable data. (C) 2021 European Association for Cranio-Maxillo-Facial
Surgery. Published by Elsevier Ltd. All rights reserved.
