Prefabrication and prelamination applications in current aesthetic facial reconstruction

The Role of Microsurgery in Burn Surgery

Acute burn reconstruction involves intricate strategies such as skin grafting and innovative technologies, addressing challenges in coverage and minimizing donor site morbidity. Despite being rarely used, flap reconstruction becomes necessary when critical structures are exposed, offering robust coverage and reducing complications. However, free flaps in acute burns face challenges, including a higher failure rate attributed to hyperinflammatory states and hypercoagulability. Surgical optimization strategies involve careful timing, patient preparation, and meticulous postoperative care. In delayed burn reconstruction, free flaps proved effective in functional and aesthetic restoration, with low flap loss rates and minimal contracture recurrence. Prefabricated and prelaminated flaps emerged as a solution for complex cases, ensuring the best functional and aesthetic possible outcomes in challenging facial burn reconstructions.

Augmentation of Perforator Flap Blood Supply with Vascular Supercharge or Flap Prefabrication: Evaluation in a Rat Model

BACKGROUND

Vascular supercharge and flap prefabrication are two surgical maneuvers to improve flap blood supply. Although these techniques have been studied intensively, few studies have focused on the differences between supercharge and prefabricated flaps regarding their flap survival areas, vasculatures, and hemodynamics.

METHODS

In this study, 21 male Sprague-Dawley rats were divided into three groups as follows: group A, single perforator flap; group B, supercharge flap; and group C, prefabricated flap. Flap survival was measured 1 week after flap elevation. Indocyanine green angiography was applied to visualize flap vascularity and to analyze flap hemodynamics. Von Willebrand factor immunohistochemical staining was applied to assess the number of microvessels in the choke zone of the abdominal wall.

RESULTS

The flap survival areas were expanded significantly in the arteriovenous supercharge group and the vascular bundle prefabricated group compared with that in the single-perforator group (81.34 ± 8.12 percent and 75.51 ± 8.08 percent versus 46.27 ± 10.01 percent, respectively; p < 0.05). Hemodynamic analysis suggested that although a significant increase in arterial infusion could be achieved with flap prefabrication, the venous effusion of the prefabricated flap was the worst among the three groups, indicating greater susceptibility to compromised venous return. Active neovascularization was confirmed by an increased number of microvessels in group C. Specifically, the dilatation of choke vessels and the newly formed vessels of the prefabricated pedicle could be appreciated by indocyanine green angiographic mapping.

CONCLUSIONS

Both vascular supercharge and flap prefabrication can augment the blood supply of the perforator flap but by means of different mechanisms. Because a supercharge flap is less susceptible to venous compromise, it is suggested to first consider the use of vascular supercharging when feasible.

Total Nasal Reconstruction With Prefabricated and Prelaminated Free Flap

Nasal reconstruction is a complex staged procedure. When optimal donor areas are unavailable, flap prefabrication and prelamination techniques can be used for total nasal reconstruction. A technique of total nasal reconstruction using neovascularization of the supraclavicular skin from a skin free flap used for internal lining, along with prelamination of the cartilage framework and surgical delays, is described in 2 patients with adverse anatomical conditions.

Augmentation of Perforator Flap Blood Supply with Sole or Combined Vascular Supercharge and Flap Prefabrication for Difficult Head and Neck Reconstruction

Importance: The strategic option between vascular supercharge and flap prefabrication in the fabrication of multipedicle flaps for difficult head and neck reconstruction has not been reported. Objectives: To summarize our 13-year experience in the design of multipedicle pre-expanded perforator flaps for extensive head and neck defect reconstruction, with vascular supercharge and flap prefabrication, either solely or in combination. To discuss the strategy for judicious selection between these techniques in the design of multipedicle flaps at different donor sites. Design, Setting, and Participants: A retrospective study was performed in patients with severe head and neck deformities and treated with multipedicle pre-expanded perforator flaps between May 2005 and May 2018. Intraoperative indocyanine green angiography was utilized for visualization of flap perfusion and analysis of the hemodynamics of pre-existing perforator and prefabricated vessels. Main Outcomes and Measures: The main outcomes measured were (1) features of deformities, (2) multipedicle flap designs, and (3) postoperative complications and long-term functional and aesthetic outcomes. Results: Seventy-five multipedicle pre-expanded perforator flaps were harvested, including 44 supercharged, 26 prefabricated, and 5 tripedicle, combining both techniques, with sizes ranging from 22 × 12 to 45 × 27 cm². Hemodynamic analysis demonstrated slower arterial inflow (0.60 ± 0.29 U/s vs. 2.65 ± 1.29 U/s, p < 0.05) and venous outflow (0.10 U/s vs. 0.23 ± 0.11 U/s) in prefabricated vessels, compared to the pre-existing perforator, namely the internal mammary arterial perforator. Partial necroses were observed in three patients with only one requiring skin grafting. The aesthetic and functional outcomes were satisfying after reconstruction. Conclusions and Relevance: Multipedicle pre-expanded perforator flaps fabricated by vascular supercharge and flap prefabrication, either solely or in combination in various donor sites, are powerful reconstructive tools for extensive head and neck defects. For a more reliable design, vascular supercharging should be considered a priority strategy, and flap prefabrication an alternative when suitable supercharging vessels are unavailable.

Medial femoral condyle free flap in combination with paramedian forehead flap for total/subtotal nasal reconstruction: Level of evidence: IV (therapeutic studies): Level of evidence: IV (therapeutic studies)

BACKGROUND

The nose is a functionally complex organ with also a critical role in aesthetics. For reconstruction of full thickness nasal defects, multiple stages are needed and there is risk for resorption resulting in residual deformity. The aim of this report was to develop and evaluate a new method for full thickness total/subtotal nose reconstruction using the medial femoral condyle free flap (MFCFF) in combination with a paramedian forehead flap.

METHODS

Between November 2015 and January 2018, eight patients (four males, four females) mean age 52 years (range 40-73 years) undergoing a total/subtotal nasal excision and subsequential reconstruction with MFCFF plus paramedian forehead flap were enrolled. Six cases were squamous cell carcinomas while two were basal cell carcinomas. The MFCFF was stabilized, with the periosteum as inner layer, with plates and a paramedian forehead flap was used as external skin coverage. All patients were evaluated for with postoperative nasal endoscopy and CT scan. A postoperative questionnaire was given 6 months after surgery.

RESULTS

The mean MFCFF size was 2-3.8 cm × 2.25-2.5 cm with a mean pedicle length of 6.3 cm (range 4.1-9.4 cm). The postoperative period was uneventful. The mean follow-up was 16 months, no bone displacement or resorption was observed at the CT scan, no evidence of nasal stenosis occurred. All patients had a satisfying aesthetic evaluation and a good subjective nasal function.

CONCLUSIONS

In this series, the MFCFF in combination with the paramedian forehead flap appeared to provide a valid subtotal nose reconstruction, allowing for the recreation of all the three nasal layers and maintaining the nose projection and airway patency in the long term.

Prelaminated extended temporoparietal fascia flap without tissue expansion for hemifacial reconstruction

BACKGROUND

Disfigurement of the face caused by postburn scars, resected congenital nevi and vascular malformations has both functional and psychological consequences. Ideal reconstruction of the facial components requires producing not only function but also the better appearance of the face. The skin of the neck, supraclavicular or cervicothoracic regions are the most commonly used and the most likely source of skin for facial reconstruction in those techniques which prefabrications with tissue expansion are used. This retrospective cohort study describes the two staged prelaminated temporoparietal fascia flap which eliminates the usage of tissue expansion by using skin graft harvested from the neck and occipital region and the application of this flap for the lower three-fourths of the face.

METHOD

5 patients received prelaminated temporoparietal fascia flap without tissue expansion for facial resurfacing. The mean age at surgery was 39, 2 years (range, 17-60 years). The average follow up was 21.6 months (range, 10-48 months).

RESULT

The size of the raised prelaminated temporoparietal fascia flaps ranged from 9 × 8 cm to 14 × 10 cm. All flaps survived after second stage. Varied degrees of venous congestion were observed after flap insets in all cases but none required any further treatment for the congestion. The entire lesion could not be resected due to the large size of the lesion in all patients.

CONCLUSION

Two stage prelaminated temporoparietal fascia flap with skin graft is an effective technique for the reconstruction of partial facial defects in selected patients. It is simple, quick, safe and reliable, and requires no expansion of skin or no microsurgery.

Esthetic Craniofacial Bony and Skull Base Reconstruction Using Flap Wrapping Technique

For a safe and esthetic skull base reconstruction combined with repair of craniofacial bone defects, the authors introduce the flap wrapping technique in this study. This technique consists of skull base reconstruction using the vastus lateralis muscle of an anterolateral thigh (ALT) free flap, and structural craniofacial bony reconstruction using an autologous calvarial bone graft. The key to this technique is that all of the grafted autologous bone is wrapped with the vascularized fascia of the ALT free flap to protect the grafted bone from infection and exposure. Two anterior skull base tumors combined with craniofacial bony defects were included in this study. The subjects were a man and a woman, aged 18 and 64. Both patients had preoperative proton beam therapy. First, the skull base defect was filled with vastus lateralis muscle, and then structural reconstruction was performed with an autologous bone graft and a fabricated inner layer of calvarial bone, and then the grafted bone was completely wrapped in the vascularized fascia of the ALT free flap. By applying this technique, there was no intracranial infection or grafted bone exposure in these 2 patients postoperatively, even though both patients had preoperative proton beam therapy. Additionally, the vascularized fascia wrapped bone graft could provide a natural contour and prevent collapse of the craniofacial region, and this gives patients a better facial appearance even though they have had skull base surgery.

Prefabricated bone flap: an experimental study comparing deep-frozen and lyophilized-demineralized allogenic bones and tissue expression of transforming growth factor β

BACKGROUND

Extensive bone defects are still a challenge for reconstructive surgery. Allogenic bones can be an alternative with no donor area morbidity and unlimited amount of tissue. Better results can be achieved after allogenic bone preparation and adding a vascular supply, which can be done along with flap prefabrication. The purpose of this study was to evaluate demineralized/lyophilized and deep-frozen allogenic bones used for flap prefabrication and the tissue expression of transforming growth factor β (TGF-β) in these bone fragments.

METHODS

Fifty-six Wistar rat bone diaphyses were prepared and distributed in 4 groups: demineralized/lyophilized (experimental group 1 and control group 2) and deep freezing (experimental group 3 and control group 4). Two bone segments (one of each group) were implanted in rats to prefabricate flaps using superficial epigastric vessels (experimental groups) or only transferred as grafts (control groups). These fragments remained in their respective inguinal regions until the death that occurred at 2, 4, and 6 weeks after the operation. Semiquantitative histologic (tetracycline marking, cortical resorption, number of giant cells, and vascularization) and histomorphometrical quantitative (osteoid thickness, cortical thickness, and fibrosis thickness) analyses were performed. Transforming growth factor β immunohistochemistry staining was also performed.

RESULTS

Group 1 fragments presented an osteoid matrix on their external surface in all periods. Cartilage formation and mineralization areas were also noticed. These findings were not observed in group 3 fragments. Group 1 had more mineralization and double tetracycline marks, which were almost not seen in group 3. Cortical resorption and the number of giant cells were greater in group 3 in all periods. Vascularization and fibrosis thickness were similar in both experimental groups. Group 1 had more intense TGF-β staining within 2 weeks of study. Nevertheless, from 4 weeks onward, group 3 presented statistically significant stronger staining.

CONCLUSIONS

Although there are some differences between the preparation methods of allogenic bone, it is possible to prefabricate flaps with demineralized/lyophilized and deep-frozen bones.

Prelaminated fascia lata free flap for large nasal septal defect reconstruction

Nasal septal defects can be challenging to repair, given their location, size, and the unique, tri-layered structure of the septum, which includes a thin piece of cartilage positioned between mucosal layers. The report herein presents a case of a 47 year-old woman with a large symptomatic nasal septal perforation, despite saline irrigations and ointment. Placement of a septal button or a traditional surgical approach was not considered because of the extremely large nature of the perforation. We describe the use of a tri-layered fascia lata flap prelaminated with buccal mucosa grafts to successfully repair this complicated defect. Subsequent follow-up visits showed complete repair of the defect and patent nasal passages, without the need for any debulking procedures. Based on these results, we conclude that a prelaminated fascia lata flap is a good reconstructive option for large, complex nasal septal defects, bringing thin, healthy mucosalized tissue to the defect and minimizing future surgical procedures.

Evolution and limitations of conventional autologous reconstruction of the head and neck

Conventional reconstruction in the head and neck has undergone a revolution as microsurgery has evolved and expanded our ability to reconstruct the most difficult defects. Vascularized composite allotransplantation (VCA) has provided a new paradigm of options to restore in 1 stage what in the past has been performed in multiple stages with multiple combinations of free flaps and local flap options. This review demonstrates an evolving perspective of head and neck reconstructive surgery incorporating the indications and advantages gained over a career that has developed in parallel with microsurgery, prefabrication, prelamination, and face transplant. All current conventional reconstructions for the most severe defects often involve multistage procedures, using every rung of the reconstructive ladder, and the end results can still be lacking despite our best efforts. Despite all the tailoring and planning of these multiple flap and multiple-stage reconstructions, in our experience, these interventions never quite exactly recapitulate the face and fall short of full restoration. The early experience with VCA has been very promising and yields results that are superior to those achieved using conventional methods of reconstruction. However, it will be synergistic efforts in both VCA and conventional reconstruction to take us to the next level of full face restoration.

Strategies for vascularization of polymer scaffolds

Biocompatible, degradable polymer scaffolds combined with cells or biological signals are being investigated as alternatives to traditional options for tissue reconstruction and transplantation. These approaches are already in clinical use as engineered tissues that enhance wound healing and skin regeneration. The continued enhancement of these material strategies is highly dependent on the ability to promote rapid and stable neovascularization (new blood vessel formation) within the scaffold. Whereas neovascularization therapies have shown some promise for the treatment of ischemic tissues, vascularization of polymer scaffolds in tissue engineering strategies provides a unique challenge owing to the volume and the complexity of the tissues targeted. In this article, we examine recent advances in research focused on promoting neovascularization in polymer scaffolds for tissue engineering applications. These approaches include the use of growth factors, cells, and novel surgical approaches to both enhance and control the nature of the vascular networks formed. The continued development of these approaches may lead to new tissue engineering strategies for the generation of skin and other tissues or organs.

Where do perforator flaps fit in our armamentarium?

This article reviews historical aspects of flap development, leading up to the exciting recognition of perforator flaps. The role and use of perforator-type flaps in the reconstructive armamentarium is reviewed as it pertains to different regions of the body.