Fluorescein Indocyanine Green Angiography Research Articles

Use of Indocyanine Green Fluorescence During Total Thyroidectomy to Identify Parathyroid Glands and Prevent Hypoparathyroidism.

Total thyroidectomy is associated with a high rate of transient or permanent hypoparathyroidism. During surgery, indocyanine green (ICG) fluorescein angiography can be used to detect and preserve well-vascularized parathyroid glands. This technique has been introduced as an intraoperative support to prevent postoperative hypoparathyroidism. One-hundred consecutive patients who had undergone total thyroidectomy were included in this study. Autofluoroscopy was used on the first dominant side of thyroidectomy and to identify the contralateral parathyroid glands. An intravenous bolus of 5 mg ICG (VERDYE, Diagnostic Green GmbH, Aschheim-Dornacht, Germany) was administered once. ICG fluorescein angiography was used as a "bridge" at the end of the first dominant hemithyroidectomy and after exposure of the parathyroid glands on the second side. This allowed us to (i) determine the vascularization of the first two parathyroid glands and (ii) define the blood vessels and thus the line of dissection of the parathyroid glands of the second resection side. Finally, autofluoroscopy was then applied outside the surgical area on the surgical specimen to assess forgotten parathyroid glands, which should therefore be re-implanted. Autofluoroscopy and ICG fluorescein angiography were evaluated in real time using the same technology, i.e., FLUOBEAM® LX (EUROPE - Fluoptics Grenoble, France; USA - Fluoptics Imaging Inc., Cambridge, MA, USA). The study was approved by the local ethics committee. Autofluorescence and ICG fluorescein angiography were performed without any problems in all cases. A total of 370 parathyroid glands were detected in this series. ICG changed the surgical strategy for the first-side parathyroid glands in 5% of cases, i.e,. they were not well-vascularized and were re-implanted. The rate of transient hypoparathyroidism was 19%. The percentage of parathyroids in the surgical specimen was 3.5% and all were re-implanted during the same surgery. There was no case of postoperative definitive hypoparathyroidism when at least one parathyroid gland with a high fluorescence intensity was preserved on the first side of resection. Use of ICG fluorescein angiography may contribute to predicting and thus preventing postoperative definitive hypoparathyroidism after total thyroidectomy. The results of this case series confirm recent studies. Caution is advised when weakly perfused parathyroid glands are discovered.

Evaluation of tissue perfusion by indocyanine green fluorescein angiography in patients with neuroischemic diabetic foot syndrome after endovascular treatment

To evaluate the fluorescence angiography (FA) parameters with Indocyanine green (ICG) and their dynamics in diabetic foot patients after endovascular treatment. A single-center prospective non-blinded study was conducted with the inclusion of 47 diabetic foot patients with Chronic limb-threatening ischemia (CLTI). TcPO2 and FA-ICG were done before and after angioplasty. Zones of interest were selected for FA-ICG: the area of minimum and maximum fluorescence, the area of of the largest part of the foot. Also presented are the parameters of FA ICG: Tstart (sec) - the time of occurrence of min fluorescence (Istart, unit) in the zone of interest after the introduction of ICG; Tmax (sec) - the time to achieve max fluorescence (Imax, unit) after the introduction of ICG; Tmax -Tstart (sec) - the difference in the time of reaching Imax and Istart. The median TcPO2 values indicated the presence of CLTI before revascularization. Technical success of revascularization was achieved in 45 patients. In the postoperative period, statistically significant changes in TcPO2 and Tstart, Tmax, Tmax-Tstar were obtained. A reduction in the time to reach the ICZ to the zones of interest was noted. FA-ICG evaluate the visual and quantitative characteristics of perfusion of soft tissues of the foot. Reducing the time to reach the fluorescent substance in the areas of interest makes it possible to assume the restoration of the main blood flow to the foot. Further investigations are warranted to determine threshold values to predict wound healing and indications for revascularization.

Application of micro-mirror in microsurgical clipping to the intracranial aneurysm

Objective To explore the value and disadvantage of micro-mirror in the intracranial aneurysm surgery. Methods Micro-mirror was used to assist microsurgical clipping to 36 intracranial aneurysms in 31 cases, of which 3 were carotid-ophthalmic artery aneurysms, 3 anterior choroidal artery aneurysm, 11 were posterior communicating artery aneurysms, 7 were middle cerebral artery aneurysms, 10 anterior communicating artery or anterior cerebral artery aneurysms, and the others were a posterior cerebral artery aneurysm and a posterior inferior cerebellar artery aneurysm. The micro-mirror was used before and after clipping to observe the anatomic features of necks hidden behind and medial to aneurysms, to visualize surrounding neurovascular structures, and to verify the optimal clipping position. Intraoperative indocyanine green fluorescein angiography confirmed the success of sufficient clipping. Results All aneurysms were clipped successfully. The parent arteries were occluded temporarily in 26 cases, and 9 aneurysms ruptured during the operation. Postoperative follow-up lasted from 2 weeks to 1 year. After operations digital subtraction angiography (DSA) were repeated in 10 cases, computed tomography angiography(CTA) in 21 cases, and no insufficient clipping or occlusion of parent arteries were revealed. Conclusions Micro-mirror assisting microsurgical clipping to the intracranial aneurysm is conducive to accurate clipping, and is a convenient and practical operation. Key words: Intracranial aneurysm; Microsurgery; Surgical instruments

Application of Multimodal Navigation together with Fluorescein Angiography in Microsurgical Treatment of Cerebral Arteriovenous Malformations

This study aimed to explore the clinical applications of multimodal navigation combined with indocyanine green (ICG) fluorescein angiography in microsurgical treatment of cerebral arteriovenous malformations (AVMs). We retrospectively collected 52 patients with AVMs. Assisted by anatomic image, we reestablished three-dimensional structure using preoperative functional magnetic resonance imaging (fMRI) and Diffusion tensor imaging (DTI). The operation for lesion resection was finished under the assistance of neuro-navigation. ICG fluorescein angiography was performed for 16 of the study subjects, meanwhile, FLOW800 was used to rebuild blood vessel color visual image. Brain angiography was performed 1 week after the operation to check residual malformations. The patients’ status was estimated by Modified Rankin Scale score. Of the AVMs, 92.3% (48/52) were totally removed, without severe side events. Among the patients, fluorescein angiography was carried out up to 58 times for 16 cases. All of these 16 cases were confirmed with malformations and 14 of them had draining vein. The total resection rate of these 16 cases reached 100%, and the occurrence rate of postoperative complications was not significantly increased. During the operation of lesion resection, the application of multimodal navigation could effectively protect functional cortex and conduction pathway.