Changing the paradigm in medial canthal reconstruction: the bridge principle and the croissant-like keystone island perforator flap as an alternative for medium size soft tissue defects in internal canthus reconstruction. J Craniofac Surg. 2018;29:e455-e459. [PMID: 29521766 DOI: 10.1097/scs.0000000000004472]

The Bridged Digital Artery Perforator Flap as an Alternative Reconstructive Option for Dorsal Digital or Toe Soft Tissue Defects

BACKGROUND

Dorsal digital soft tissue defects are considered among the most challenging to reconstruct. Numerous treatment options are proposed, including advancement flaps, antegrade, retrograde flow flaps, adipofascial flaps, and digital artery perforator flaps. However, the optimal treatment remains controversial. The concept of the "bridge principle," consisting of the indirect transfer of the flap to the defect area through a muscular bridge, has recently introduced by authors for medial canthal reconstruction. The aim of the study was to examine the feasibility of its application in digital reconstruction for dorsal defects and the development of a new flap. The utilization of the dorsal subcutaneous adipofascial digital or toe tissue as a "bridge" led to description and development of bridged digital artery perforator flaps as an alternative treatment of such defects.

METHODS

From November 2017 to September 2019, a series of 14 patients (mean age of 57.1 years) suffered from dorsal digital or toe soft tissue defects of different dimensions and sustained reconstruction with this new technique.

RESULTS

Twelve digits and 2 toes have been concerned. The mean size of the defects was 1.3 × 1.1 cm. All flaps survived without a sign of venous congestion. No functional digital or toe problems were observed during the follow-up period (mean of 11.6 months). Minor wound dehiscence presented in 2 cases (2 of 14 [14.3%]) and a transient skin swelling around the flap in 1.

CONCLUSIONS

A new concept was introduced to resolve a challenging problem. Initial outcomes are very encouraging. These flaps could be a valuable and reliable reconstructive option.

Outcomes of the Keystone Island Perforator Flap: A Systematic Review

BACKGROUND

 The Keystone Design Perforator Island Flap (KDPIF), first described by Behan in 2003, has been demonstrated as a versatile, safe, and straightforward reconstructive option for various soft tissue defects. The purpose of this systematic review is to evaluate the indications, variations, and overall complication profile of the keystone flap in reconstructive surgery.

METHODS

 A literature review was conducted in accordance with PRISMA guidelines using MeSH term "surgical flaps" with the keyword "keystone flap." Empirical studies with at least 15 patients who underwent keystone flap reconstruction were assessed for quantitative analysis. Outcomes of interest included patient demographics, indications, anatomic location, flap design, and complications.

RESULTS

 Database search produced 135 articles, of which 25 were selected for full-text review. Out of 23 studies selected qualitative analysis and 22 met criteria for quantitative analysis. Overall success rate of this flap was 98%. Wound complications were highest in extremity flaps. Several modifications of this flap were described.

CONCLUSION

 Keystone reconstruction demonstrates excellent success rates and versatility. However, further studies with more standard reporting are needed to determine guidelines for patient specific surgical planning.

Keystone Flaps: Physiology, Types, and Clinical Applications

The keystone perforator flap (KPF) was first introduced in 2003 by Behan et al for use in reconstruction after skin cancer excision. Since its initial description, KPF use has been expanded to complex defects of various etiologies and disorders throughout the body. At its most basic, the KPF is a perforator-type flap designed with a 1:1 flap-to-defect width ratio. Keystone perforator flaps are specifically raised on pedicles arising from musculocutaneous or fasciocutaneous perforator vessels. Major advantages of the KPF derive from the maintenance of perforator vascular territories, perforosomes, permitting increased flap viability. In turn, this allows for more aggressive undermining in sites away from perforators when greater skin mobilization is necessary. Furthermore, the KPF is relatively easy to perform leading to shorter operative times and no postoperative monitoring period. There are basically 4 different types of keystone flaps in order of increasing undermining and disturbance of underlying fascia. These different classifications of KPFs may be used in different anatomical locations over the entire body based on skin laxity and defect size/depth. Numerous advancements and modifications have been documented adapting the KPF to specific conditions, including myelomeningoceles, and scrotal and lower eyelid defects. The purpose of this article is to provide an organized review of the KPF with emphasis on different classifications, applications, and limitations as well as an overview of the surgical technique. We have additionally included a discussion on KPF physiology and review of current literature.

Keystone design perforator island flap in facial defect reconstruction

Facial defect coverage is a common subject in the field of reconstructive surgery. There are many methods for facial defect reconstruction, and reconstructive surgeons should choose the most appropriate method on a case-by-case basis to achieve both functional and aesthetic improvement. Among various options for facial reconstruction, the local flap technique is considered the best reconstructive modality to provide good tissue matches of color and texture, which is consistent with the ideal goal of reconstruction (replacement of like-with-like). Keystone design perforator island flap (KDPIF), devised by Behan in 2003, has been applied to various fields of reconstructive surgery in the past decade due to its design simplicity, robust vascular supply, and reproducibility. Several studies have reported KDPIF reconstruction of facial defects, such as large parotid defects, small-to-moderate nasal defects, and eyelid defects. However, KDPIF has been used relatively less in facial defects than in other body regions, such as the trunk and extremities. The purpose of this review is to provide an organized overview of facial KDPIF reconstruction including the classification of KDPIF, modifications, physiology, mechanism of flap movement, consideration of facial relaxed skin tension lines and aesthetics, surgical techniques, clinical applications, and precautions for successful execution of KDPIF reconstruction.