
==== Front
Plast Reconstr Surg Glob Open
Plast Reconstr Surg Glob Open
GOX
Plastic and Reconstructive Surgery Global Open
2169-7574
Lippincott Williams & Wilkins Hagerstown, MD

GOX-D-24-00774
00017
10.1097/01.GOX.0001063876.67271.f6
3
PSTM Abstract Supplement
PSTM Top Abstracts/Posters 2024
Effects of Hypoxia and Lymphangiosclerosis Due to Damage to the Vasa Vasorum of the Collecting Lymph Vessels in Lymphedema
Matsui Chihiro MD 1
Tsukuura Reiko MD 1
Sakai Hayahito MD 1
Miyazaki Toko 1
Mortada Hatan MD 1
Deguchi Ayaka N. MD 1
Mizuno Hiroshi MD 1
Yamamoto Takumi MD 1
Department of Plastic and Reconstructive Surgery, National Center for Global Health and Medicine, Tokyo, Japan, Department of Plastic and Reconstructive Surgery, Juntendo University School of Medicine, Tokyo, Japan
9 2024
18 9 2024
12 Suppl 12-13Copyright © 2024 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of The American Society of Plastic Surgeons. All rights reserved.
2024
https://creativecommons.org/licenses/by-nc-nd/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.

OPEN-ACCESSTRUE
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pmcOBJECTIVE: Smooth muscle cells are found along pre-collecting and collecting lymphatic vessels, and their function depends on adequate blood supply. The structure of the vasa vasorum of the collecting lymph vessels (VVCL) has been studied, but their physiological role is not well understood. This research aims to examine the relationship between VVCL morphology and blood circulation in limbs with lymphedema, as well as validate ischemic conditions affecting lymphatic vessels.

METHODS: The medical records of patients with lower extremity lymphedema who underwent video capillaroscopy during supermicrosurgical lymphaticovenous anastomosis (LVA) surgery were reviewed. The collecting lymph vessels, which were dissected for LVA, were examined using video capillaroscopy (GOKO Bscan-ZD, GOKO Imaging Devices Co., Japan) at 175x and 620x magnification. Software (GOKO-VIP ver. 1.0.0.4, GOKO Imaging Devices Co.) calculated the blood flow velocity of the vasa vasorum of the collecting lymph vessels (VVCL) by measuring red blood cell movement. Based on the video capillaroscopy findings, the VVCL were categorized by morphology, and the morphology types and blood flow velocity of VVCL were compared with the severity grade of lymphosclerosis. Additionally, to investigate the pure effects of hypoxia on lymph endothelial cells, a migration assay of human dermal lymphatic endothelial cells (HDLECs) was performed in hypoxic culture to determine the migration rate of the cells.

RESULTS: The medical records of 20 patients with lower limb lymphedema who had lymphaticovenous anastomosis (LVA) surgery were examined. A total of 67 lymph vessels were evaluated, with varying degrees of lymphosclerosis severity graded as s0 to s3. Video capillaroscopy was used to visualize the vasa vasorum of the collecting lymph vessels (VVCL). The VVCL were categorized into 4 morphology types based on the video images. Blood flow velocity in the VVCL ranged from 0 to 189.3 mm/sec, with an average of 26.40 mm/sec. Statistically significant differences were found in both VVCL morphology and blood flow velocity according to lymphedema severity grade. The diameters of the main VVCL and branches were measured, ranging from 0 to 0.096 mm and 0 to 0.053 mm respectively. Additionally, a migration assay was performed on human lymphatic endothelial cells. The migration rate was 6.344% under normal oxygen conditions and 2.172% under hypoxic conditions after 6 hours, demonstrating hypoxia significantly reduced migration (P=0.00057).

CONCLUSION: This study found the vasa vasorum of collecting lymph vessels can be categorized into four types, each with distinct features. Changes in the morphology and physiology of the vasa vasorum of collecting lymph vessels (VVCL) are linked to sclerotic changes caused by ischemia affecting these vessels. Additionally, the hypoxic conditions in lymphatic vessels resulting from VVCL damage directly impairs the migratory ability of lymphatic endothelial cells. This may be responsible for worsening of lymphedema.
