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Pandey et al. Plast Aesthet Res 2021;8:47 https://dx.doi.org/10.20517/2347-9264.2021.61 Page 3 of 12

- not nodes - are the therapeutic components of these flaps [39,40] .

Vascularized lymph vessel transplant - the third surgical alternative
[5]
Vascularized lymph vessel transplant was introduced by Koshima et al. in 2016 when they used first dorsal
metatarsal artery (FDMA)-based lymphadiposal flaps on treating advanced lymphedema in thirteen
patients. It represented a conceptual departure from the accepted belief that nodal tissue transfer is required
to restore of lymphatic drainage. Subsequently, the senior author implemented FDMA-based VLVT with
favorable recipient-site outcomes. However, the location of the donor site precluded the flap’s use in
bilateral lower extremity disease. Additionally, FDMA flap harvest frequently caused devascularization of
the skin over the first metatarsal space, resulting in donor wound breakdown . Nevertheless, the success of
[7]
the procedure drove the senior author to establish alternative lymphatic-rich donor sites: the groin
[superficial circumflex iliac artery perforator (SCIP) flap] and trunk [thoracodorsal artery perforator
[6]
(TDAP) flap] . The SCIP flap’s familiar vascular anatomy and successful use as a thin flap make it an ideal
candidate for VLVT. However, the SCIP flap is not a feasible option in patients with bilateral lower
extremity lymphedema. The TDAP flap’s location makes it suitable for bilateral lower extremity disease and
contralateral upper extremity disease. Our early outcomes show similar efficacy and safety profiles to that of
the SCIP flap. As shown in Figure 1, satisfactory decompression of the lymphedematous limb with minimal
complications is achievable. By selectively harvesting only lymph vessels and completely preserving lymph
nodes, VLVT greatly reduces the risk of donor-site complications while still offering results comparable to
VLNT. As of the writing of this article, the senior author (Chen WF) has completely replaced VLNT with
VLVT in his practice for the treatment of advanced fluid-predominant lymphedema.

Revisiting the indications for LVA
As surgeons’ worldwide developed expertise in supermicrosurgery, the practice of LVA grew in
sophistication. New technology and techniques further enhanced an already efficacious procedure.
[41]
[42]
Indocyanine green (ICG)-lymphographic , infrared , and high-frequency duplex ultrasound [43,44]
guidance facilitates the precise placement of small incisions with high success rates. Different anastomotic
configurations were developed to increase the number of drainage pathways and to successfully complete
LVA even under technically challenging conditions [45,46] . These technical innovations allowed
supermicrosurgeons to successfully treat even advanced lymphedema cases with LVA when these cases were
previously considered only treatable with VLNT. Because VLVT and VLNT have similar indications, with
the expanding scope of LVA, indications for LVA and VLVT/VLVT have started to overlap.

Technical tips: LVA
Vessel mapping and dissection
Incisions for LVA are planned where ICG-mapped lymph vessels and infrared-mapped veins lie in close
proximity, as shown in Figure 2, maximizing the possible number of LVAs created per incision [47-51] . The
anatomy of the superficial lymphatic system closely follows that of the superficial venous system; thus, in
advanced cases with difficult-to-identify lymphatics, careful dissection along main superficial veins can still
reveal suitable lymph vessels , as shown in Figure 3. In these advanced cases, any dermal backflow pattern
[52]
on delayed images of diagnostic ICG lymphography suggests the presence of lymphostatic choke points.
LVAs incisions should ideally be placed anatomically in or just proximal to these dermal backflow patterns.
Injection of isosulfan blue 2 cm distal to skin markings just before each incision enhances identification of
[52]
lymphatic vessels during dissection . We use 20-25x magnification and proceed in a caudo-cephalad
direction . All dissected lymphatics are inspected and graded as healthy, ectatic (mild injury), contracted
[48]
(moderate injury), or sclerotic (severe injury) [16,53] . Although healthy vessels are preferred, ectatic and
contracted vessels can also be used when necessary to achieve a sufficient number of LVAs per case [47,54] .