Supermicrosurgery: History, Applications, Training and the Future

Robot-Assisted Microsurgery-what does the learning curve look like?

Background

The introduction of robotic assistance in surgical practice has led to advancements such as the MUSA-2 robotic system that was designed for microsurgical procedures. Advantages of this system include tremor filtration and motion scaling. Initial studies showed promising results in skill acquisition for robot-assisted microsurgery. This study evaluated the learning curve for microsurgical anastomosis with and without robotic assistance among surgeons of varying experience levels.

Methods

Fifteen surgeons were divided into 3 groups (novice, intermediate, and expert) based on their microsurgical experience. They performed 10 anastomoses by hand and 10 with robotic assistance on synthetic polyvinyl alcohol vessels (diameter of 2 mm) in a laboratory setting. Participants were timed and mistakes such as backwall and leakage were assessed and recorded. Demographic information was collected.

Results

Statistical differences were found in manual anastomosis times between the intermediate and novice groups compared to the experts (p < 0.01). However, no statistical difference was found in the mean time between groups for the robot-assisted anastomoses. Novice doctors had the steepest learning curve for hand-sewn anastomosis. Experts had the fastest completion time at the end of the 10th robotic session, finishing at 14 min, compared to 33 min at the 2nd session. All groups reduced their mean time in half through their 10 robotic sessions.

Conclusion

This study indicated similarities in the learning curves for robot-assisted anastomosis among surgeons with varied experience levels. Experts excelled technically in manual anastomoses, but robot-assistance enabled novice and intermediate surgeons to perform comparably to the experts. Robotic assistance may aid more novice learners in performing microsurgical anastomosis safely at earlier points in their education.

Learning curve of robotic assisted microsurgery in surgeons with different skill levels: a prospective preclinical study

Achieving precision in microsurgery requires skill, adequate instruments and magnification, as well as extensive training. Dedicated surgical robotic systems have enhanced and expanded the application of (super-)microsurgical techniques by introducing motion scaling and providing improved surgeon ergonomics. In this prospective preclinical trial, we analyzed the learning curve in robotic assisted microsurgery in 13 participants including medical students, residents, and attending physicians. Data on demographics as well as prior experience in surgery, microsurgery, and gaming were collected. In three study sessions, the participants performed nine microsurgical anastomoses each on 2 mm vessel models using the Symani® Surgical System in combination the VITOM 3D exoscope. A senior expert microsurgeon reviewed the de-identified and blinded videos and scored all anastomoses using a modified "Structured Assessment of Microsurgical Skills" (SARMS) score. All participants significantly reduced their time needed per anastomosis and their overall SARMS score, as well as individual scores for motion and speed throughout the trial. We saw a significant correlation of prior years of practice in surgery with the overall mean time and mean SARMS score. In a separate analysis of the three sessions, this influence could no longer be seen in the last session. Furthermore, we found no significant effect of gender, age, hand dominance, or gaming experience on speed and quality of the anastomoses. In this study of 117 robotic assisted anastomoses, a rapid improvement of performance of all participants with different surgical skills levels could be shown, serving as encouraging evidence for further research in the implementation of microsurgical robotic systems.

Microvascular Ear Replantation: A Multicenter Study of 22 Patients with Complete Ear Amputation

Background: We aimed to report our experience in treating ear amputations with microvascular replantation, with the largest sample to date. Methods: Twenty-two patients with complete ear amputation underwent microvascular ear replantation at three medical centers between May 2003 and May 2020. Arterial anastomoses, venous anastomoses, or vein graft were performed depending on different situations. Re-exploration was performed in four patients due to venous congestion (n = 3) or arterial compromise (n = 1). Results: Eleven patients had vascular complications (venous congestion: 10, arterial compromise: 1) and four of them required re-exploration. Three ears were completely salvaged (75%) and one case failed. Eighteen (81.8%) replanted ears survived completely, with 15 repaired ears demonstrating a good contour and 3 ears showing atrophy. Three replanted ears sustained partial loss, and one sustained total loss. Three extraordinary cases with the longest ischemic time, smallest tissue size, and youngest age reported thus far all survived and had cosmetically satisfactory appearances. Statistical analysis indicated no significant correlation between replanted ear survival and potentially influential factors, including ischemic time, number of arterial and venous anastomoses, presence of vein graft, and re-exploration. Conclusions: Microvascular replantation for ear amputations achieved excellent results. It may be considered the primary choice for surgeons with microsurgical skill.

Lymphaticovenous Anastomosis and Vascularized Lymph Node Transfer for the Treatment of Lymphedema-A Canadian Case Series

Introduction: Lymphedema is a chronic and debilitating condition. This study aims to assess the efficacy and safety of lymphaticovenous anastomosis (LVA) and vascularized lymph node transfers (VLNT) for the treatment of patients suffering from lymphedema, mainly by comparing pre- and postoperative daily compression use, limb volumes, and occurrence of cellulitis. Methods: We performed a retrospective analysis of patients who were treated by a single surgeon for lymphedema with LVA and/or VLNT between March 2018 and February 2020. Eighteen limbs met the inclusion criteria. The severity of lymphatic dysfunction was assessed by indocyanine green lymphangiography. Patients with patent vessels were offered LVA, whereas those without were offered VLNT. Pre- and postoperative circumferential limb measurements, use of compression garments, and postoperative complications were compared. Results: Nine limbs underwent LVA, 8 underwent VLNT, and one both. The minimum follow-up was 12 months. Postoperatively, all but 3 patients (83%) were able to cease daily compression. When considering excess limb volumes, the average reduction was 58%. This reduction was achieved despite compression weaning. Forty-four percent of patients (8) reported episodes of recurrent cellulitis preoperatively, while postoperatively, only 3 of those patients (17%) experienced cellulitis, which was statistically significant (P  =  .018). No surgical complications occurred. Conclusions: Patients with lymphedema can benefit from LVA and VLNT surgery. An important effect of surgery is decreased dependence on daily compression garments to maintain a stable and reasonable limb volume. The reduction of limb circumference after 1 year was similar to LVA and VLNT. Episodes of cellulitis were significantly lower after the intervention.

Investigation of air bubble behaviour after gas embolism events induced in a microfluidic network mimicking microvasculature

Gas embolism is a medical condition that occurs when gas bubbles are present in veins or arteries, decreasing blood flow and potentially reducing oxygen delivery to vital organs, such as the brain. Although usually reported as rare, gas embolism can lead to severe neurological damage or death. However, presently, only limited understanding exists regarding the microscale processes leading to the formation, persistence, movement, and resolution of gas emboli, as modulated by microvasculature geometrical features and blood properties. Because gas embolism is initially a physico-chemical-only process, with biological responses starting later, the opportunity exists to fully study the genesis and evolution of gas emboli using in vitro microfluidic networks mimicking small regions of microvasculature. The microfluidics networks used in this study, which aim to mimic microvasculature geometry, comprise linear channels with T-, or Y-junction air inlets, with 20, 40, and 60 μm widths (arterial or venous), and a 30 μm width honeycombed network (arterial) with three bifurcation angles (30°, 60°, and 90°). Synthetic blood, equivalent to 46% haematocrit concentrations, and water were used to study the modulation of gas embolism-like events by liquid viscosity. Our study shows that (i) longer bubbles with lower velocity occur in narrower channels, e.g., with 20 μm width; (ii) the resistance of air bubbles to the flow increases with the higher haematocrit concentration; and lastly (iii) the propensity of gas embolism-like events in honeycomb architectures increases for more acute, e.g., 30°, bifurcation angles. A dimensionless analysis using Euler, Weber, and capillary numbers demarcated the conditions conducive to gas embolism. This work suggests that in vitro experimentation using microfluidic devices with microvascular tissue-like structures could assist medical guidelines and management in preventing and mitigating the effects of gas embolism.

The N-LVA Study: effectiveness and cost-effectiveness of lymphaticovenous anastomosis (LVA) for patients with cancer who suffer from chronic peripheral lymphoedema - study protocol of a multicentre, randomised sham-controlled trial

INTRODUCTION

Cancer-related lymphoedema is one of the most debilitating side-effects of cancer treatment with an overall incidence of 15.5%. Patients may suffer from a variety of symptoms, possibly resulting in a diminished health-related quality of life (HRQoL). A microsurgical technique known as lymphaticovenous anastomosis (LVA) might be a promising treatment option. The objective of this study is to evaluate whether LVA is effective and cost-effective compared with sham surgery in improving the HRQoL.

METHODS AND ANALYSIS

A multicentre, double-blind, randomised sham-controlled trial conducted in three university hospitals in the Netherlands. The study population comprises 110 patients over the age of 18 years with unilateral, peripheral cancer-related lymphoedema, including 70 patients with upper limb lymphoedema and 40 patients with lower limb lymphoedema. A total of 55 patients will undergo the LVA operation, while the remaining 55 will undergo sham surgery. The follow-up will be at least 24 months. Patients are encouraged to complete the follow-up by explaining the importance of the study. Furthermore, patients may benefit from regular monitoring moments for their lymphoedema. The primary outcome is the HRQoL. The secondary outcomes are the limb circumference, excess limb volume, changes in conservative therapy, postoperative complications, patency of the LVA and incremental cost-effectiveness.

ETHICS AND DISSEMINATION

The study was approved by the Medical Ethical Committee of Maastricht University Medical Center on 20 September 2023 (NL84169.068.23). The results will be presented at scientific conferences and published in peer-reviewed medical journals.

TRIAL REGISTRATION NUMBER

NCT06082349.

Use of supermicrosurgery in craniofacial and head and neck soft tissue reconstruction: a systematic review of the literature and meta-analysis

Supermicrosurgery is an evolving approach in the reconstruction of head and neck (HN) and craniofacial (CF) defects. This systematic review aims to evaluate the use of supermicrosurgery for arterial or combined arterial and venous anastomoses in the reconstruction of HN and CF soft tissue defects, and the associated success, total complication, and reoperation rates. A literature search was conducted on PubMed, Dynamed, DARE, EMBASE, Cochrane, and British Medical Journal (BMJ) electronic databases (PROSPERO ID: CRD42023476825). Nine studies fulfilled the inclusion criteria with 35 patients who underwent soft tissue reconstructive procedures using supermicrosurgery. Twenty-one flaps were performed on 20 patients (57.1%) with the remaining 15 patients (42.9%) undergoing supermicrosurgical replantation. The most common pathology requiring reconstruction was HN trauma (n = 16, 45.7%) followed by malignancy (n = 15, 42.9%). The pooled success rate for supermicrosurgery was 98% (95% CI 90 to 100, p = 1.00; I2 = 0%). The cumulative complication rate across all the studies was 46% (95% CI 13 to 80, p < 0.01; I2 = 0%), and the pooled rate of reoperation was 1% (95% CI 0 to 8, p = 0.23; I2 = 24%). The use of supermicrosurgery for HN and CF soft tissue reconstruction has an overall success rate of 98%, which is commensurate with traditional microsurgery for HN reconstruction. Complication and reoperation rates are comparable to previous literature. This study confirms the feasibility of supermicrosurgery as a safe and reliable reconstructive option for HN and CF defects.

Supermicrosurgery with perforator-to-perforator anastomoses for lower limb reconstructions - A systematic review and meta-analysis

BACKGROUND

Supermicrosurgical flaps based on perforator-to-perforator microanastomoses have been described for lower limb reconstruction. This approach offers the benefit of raising short pedicles while sparing axial vessels, which effectively enables complex reconstructive techniques in comorbid patients at high risk of reconstructive failure. The aim of our study is to assess the surgical outcomes of perforator-to-perforator based flaps in comparison to conventional free flaps for reconstructions of the lower limb district, through a systematic review of literature and meta-analysis.

METHODS

A search on PubMed, Embase, Cohrane, and Web of Science was performed between March-July 2022. No restrictions were placed on study date. Only English manuscripts were assessed. Reviews, short communications, letters, correspondence were excluded after reviewing their references for potentially relevant studies. A Bayesian approach was used to conduct the meta-analysis comparing flap-related outcomes.

RESULTS

From 483 starting citations, 16 manuscripts were included for full-text analysis in the review, and three were included in the meta-analysis. Out of 1556 patients, 1047 received a perforator-to-perforator flap. Complications were reported in 119 flaps (11.4%), which included total flap failure in 71 cases (6.8%), partial flap failure in 47 cases (4.5%). Overall flap complications had a HR of 1.41 (0.94-2.11; 95% C.I.). Supermicrosurgical and conventional microsurgical reconstructions were not associated with statistically significant differences (p = .89).

CONCLUSION

Our evidence supports the safety of surgical outcomes, with acceptable flap complication rates. Nevertheless, these findings are limited by poor overall quality which must be addressed and used to encourage higher-level evidence in the field.

Robotics in Screening, Diagnosis and Treatment of Breast Cancer: A Perspective View

This perspective article aims to summarize and provide an outlook for developments around the use of robotics in the screening, diagnosis and treatment of breast cancer. We searched existing literature on the design and development of new systems and the current use of pre-existing surgical robotic systems. Robotic interventions for breast palpation and biopsy under ultrasound and MRI guidance are being developed and tested on simulated breast phantoms. Results are comparable to those achieved by clinicians; however, there are yet to be any human trials. Existing robotic surgical systems have been evaluated in human trials to perform nipple-sparing mastectomy and harvesting of autologous tissue for breast reconstruction. Results are comparable to traditional NSM and demonstrate positive short-term outcomes for patients. Robotic devices could revolutionize the clinical workflow around breast cancer through less invasive surgery, greater accuracy in biopsies and microsurgery and a potential reduction in clinicians' workload. However, more research into the practical deployment of these devices and concrete scientific evidence of better patient outcomes is needed.

Supermicrosurgery: past, present and future

Supermicrosurgery was popularised in 1997 and is defined as a technique of microvascular anastomosis for single nerve fascicles and vessels 0.3-0.8 mm in diameter. It requires the use of powerful microscopes, ultradelicate microsurgical instruments and specialist dyes. The development of supermicrosurgery has vastly improved the ability of microsurgeons to create true perforator flaps with minimal donor site morbidity for reconstructive surgery and improved the precision of additional microsurgical techniques. This review outlines the origins and history of supermicrosurgery, its current applications in reconstructive surgery (including fingertip reconstructions, true perforator flap surgery, nerve flaps and lymphoedema surgery), supermicrosurgery training and future directions for the field.

Successful replantation of amputated facial tissues by supermicrosurgery

BACKGROUND

Although replantation of amputated facial segments remains challenging in reconstructive surgery, it offers excellent aesthetic and functional outcomes.

METHODS

From May 2004 to October 2019, 12 patients underwent replantation of amputated facial tissues by supermicrosurgery. The case details, such as the rationale for replantation, the operation method, and postoperative therapy, are described. Four cases are discussed to demonstrate the replantation of different facial parts.

RESULTS

Facial tissue replantation was successful in all 12 patients without secondary surgery. The cases included the nose (1 patient), ears (8 patients), lips (2 patients), and one of the soft tissue segments surrounding the lower jaw. Venous congestion occurred in three patients who received a solitary arterial repair and were treated with bloodletting. All patients expressed satisfaction with the cosmetic and functional results at the final follow-up.

CONCLUSIONS

Supermicrosurgical facial tissue replantation is a promising and effective procedure for providing patients with the best aesthetic and functional outcomes.

Robotics in Microsurgery and Supermicrosurgery

Microsurgery has changed the ability to perform highly precise and technical surgeries through the utilization of high-powered microscopes and specialized instruments to manipulate and repair anatomical structures as small as a few millimeters. Since the first human trials of robotic-assisted microsurgery in 2006, the expansion of microsurgery to supermicrosurgery (luminal diameter less than 1 mm) has enabled successful repair of previously inaccessible structures. Surgical robotic systems can offer two distinct operative advantages: (1) minimal access surgery-by entering body cavities through ports, flap harvest can be redesigned to affect a minimally invasive approach for flaps such as the rectus abdominis muscle, the latissimus flap, and the deep inferior epigastric perforator flap; and (2) precision-by eliminating physiologic tremor, improving ergonomics, increasing accessibility to difficult spaces, and providing motion scaling, precision is significantly enhanced. Robotic-assisted microsurgery is a promising application of robotics for the plastic surgeon and has played an important role in flap harvest, head and neck reconstruction, nerve reconstruction, gender-affirming surgery, and lymphatic reconstruction-all the while minimizing surgical morbidity. This article aims to review the history, technology, and application of microsurgery and supermicrosurgery in plastic surgery.

Use of the superficial inferior epigastric vein in breast reconstruction with a deep inferior epigastric artery perforator flap

Background

Autologous breast reconstruction is highly regarded in reconstructive surgery after mastectomy. DIEP flap reconstruction represents the gold standard for autologous breast reconstruction. The major advantages of DIEP flap reconstruction are its adequate volume, large vascular caliber and pedicle length. Despite reliable anatomy, there are procedures where the plastic surgeon's creativity is required, not only to shape the new breast, but also to overcome microsurgical challenges. An important tool in these cases is the superficial epigastric vein (SIEV).

Methods

150 DIEP flap procedures performed between 2018 and 2021 were retrospectively evaluated for SIEV use. Intraoperative and postoperative data were analyzed. Rate of anastomosis revision, total and partial flap loss, fat necrosis and donor site complications were evaluated.

Results

In a total of 150 breast reconstructions with a DIEP flap performed in our clinic, the SIEV was used in 5 cases. The indication for using the SIEV was to improve the venous drainage of the flap or as a graft to reconstruct the main artery perforator. Among the 5 cases, no flap loss occurred.

Conclusions

Use of the SIEV is an excellent method to expand the microsurgical options in breast reconstruction with DIEP flap surgery. It provides a safe and reliable procedure to improve venous outflow in cases of inadequate outflow from the deep venous system. The SIEV could also provide a very good option for fast and reliable application as an interposition device in case of arterial complications.

The use of the chimeric conjoint flap technique for complex defects reconstruction throughout the body: Clinical experience with 28 cases

BACKGROUND

Large soft tissue defects reconstruction represents a frequent and complex challenge in plastic surgery. A critical point regards the equilibrium between the need of large amount of tissue, while minimizing donor site morbidity. This is a common issue that plastic surgeons face in their clinical practice. In this context, the chimeric conjoint flap technique can be a valuable option, allowing to better exploit many well-known procedures. The purpose of the present work is to show the reconstructive efficacy and reliability of this technique resorting to many different well-known flaps. No such a comprehensive collection of cases is available so far dealing with this procedure.

PATIENTS AND METHODS

Twenty-eight patients presenting large defects throughout the body were treated by means of different flaps, designed according to the chimeric conjoint flap concept. Patients' mean age was 61.9 years old (range 18-82 years), 20 were males and 8 females. The size of the defects ranged from 7 cm × 6 cm to 25 cm × 18 and presented shapes or localizations that were complex to be covered with a regular flap. The defects were located in 11 cases in the lower limbs, in 9 cases in the head and neck region, in 5 cases in the groin, and in 2 cases in the thorax. Cause of the defect was tumor resection in 20 cases, trauma-induced necrosis in 5 cases, Fournier's gangrene in 2 cases, and a chronic ulcer in 1 case. Fourteen flaps were free flaps while 14 were pedicled flaps. The chimeric conjoint flap technique consists in splitting the skin paddle a flap into two smaller island that can be rearranged in order to match the particular requirements of the recipient site. Different flaps were employed: the anterolateral thigh (ALT) flap was used in 19 cases, latissimus dorsi (LD) musculocutaneous flap in 4 cases, deep inferior epigastric (DIEP) in 3 cases, medial sural artery perforator (MSAP) in 1 case, free radial forearm flap (RFFF) in 1 case.

RESULTS

All the 28 patients were successfully treated. In 6 cases minor complications were encountered, 5 at recipient site and 1 at donor site, who were all managed conservatively. No second procedures were required. The mean follow-up period was 8.4 months (range 3-12 months). At the last follow-up evaluation all the patients reached an acceptable cosmetic result and, when limbs were affected, complete range of motion restoration.

CONCLUSIONS

The present case series provide promising evidence regarding the reliability and versatility of the chimeric conjoint flap technique for large and delicate defect reconstructions throughout the body.

[Comparative analysis of the groin and SCIP flap in reconstructive microsurgery of soft tissues of the maxillofacial area and oral cavity]

Most of the articles on the groin flap were published in the period from 1975 to 2010, from 2015 to 2022, the SCIP flap surpassed the groin flap in the number of publications. According to the results of a literature search in PubMed and RINC, 30 articles were found and selected, including 288 flaps from the iliac region. The length of the vascular pedicle, the diameter of the vessels, the complications, the prevalence of the flap in the reconstruction of the head and neck, the thickness and the size of the flap were evaluated. Both of these flaps have the same nutrition, but different levels of dissection. In comparison with the groin flap, the SCIP flap has a longer vascular pedicle, which can be enlarged due to new techniques, which also allows it to be used as an ultra-thin flap, and it reduces the need for secondary procedures for defatting and reduces the risks of the complications in the donor area. The thickness of the SCIP flap is less than the groin one, which, according to the author, increases the aesthetic level of operations in the facial area in the case of the texture and color of the flap. Vascular anatomy of the SCIP flap is variable, therefore, the use of preoperative planning is necessary. Despite this, complications in the donor or recipient area during reconstruction with a SCIP flap are minimal. It has been proved that the SCIP flap is versatile and safe in all aspects of reconstruction. It can be concluded that the SCIP flap should be considered as a «workhorse» in reconstructive microsurgery of soft tissues of the throat and oral cavity.

Neuroenhancement of surgeons during robotic suturing

BACKGROUND

The initial phases of robotic surgical skills acquisition are associated with poor technical performance, such as low knot-tensile strength (KTS). Transcranial direct-current stimulation (tDCS) can improve force and accuracy in motor tasks but research in surgery is limited to open and laparoscopic tasks in students. More recently, robotic surgery has gained traction and is now the most common approach for certain procedures (e.g. prostatectomy). Early-phase robotic suturing performance is dependent on prefrontal cortex (PFC) activation, and this study aimed to determine whether performance can be improved with prefrontal tDCS.

METHODS

Fifteen surgical residents were randomized to either active then sham tDCS or sham then active tDCS, in two counterbalanced sessions in a double-blind crossover study. Within each session, participants performed a robotic suturing task repeated in three blocks: pre-, intra- and post-tDCS. During the intra-tDCS block, participants were randomized to either active tDCS (2 mA for 15 min) to the PFC or sham tDCS. Primary outcome measures of technical quality included KTS and error scores.

RESULTS

Significantly faster completion times were observed longitudinally, regardless of active (p < 0.001) or sham stimulation (p < 0.001). KTS was greater following active compared to sham stimulation (median: active = 44.35 N vs. sham = 27.12 N, p < 0.001). A significant reduction in error scores from "pre-" to "post-" (p = 0.029) were only observed in the active group.

CONCLUSION

tDCS could reduce error and enhance KTS during robotic suturing and warrants further exploration as an adjunct to robotic surgical training.

Versatility of perforator flaps for lower extremity defect coverage: Technical highlights and single center experience with 87 consecutive cases

BACKGROUND

Lower extremity defects have been and remain one of the greatest challenges in reconstructive surgery. Perforator flaps have been accepted as a valid procedure to cover such a defect. Different techniques have been described and nowadays many options are available. However, there were not studies that comprehensively review the most modern techniques and clinical application of the use of perforator flaps in the lower extremity reconstruction. In the present report, we gathered most of them, presenting an updated and large case series where different pedicled and free perforators flaps were employed in simple and complex scenarios in a large series of cases.

PATIENTS AND METHODS

Eighty-seven patients presenting soft tissue defects of the lower extremities were treated by means of different perforator-based flaps, in either free or pedicled fashion. The flaps were based on different perforator vessels, namely deep lateral circumflex femoral artery, profunda femoris artery, superficial femoral artery, medial sural artery, peroneal artery, posterior tibial artery, anterior tibial artery, and medial plantar artery. Patients' mean age was 61.9 years old (range 21-87 years old), 58 were males and 29 females. The 12 patients received sequential flaps and 9 received double free flaps, for a total sum of 106 flaps. The causes of the defects were trauma in 41 patients and tumors in 46 patients, located throughout the lower limbs. Size of the defect ranged from 3 cm × 4 cm to 25 cm × 9 cm.

RESULTS

The dimensions of the flap skin paddles ranged from 3 cm × 4 cm to 16 cm × 5 cm for the pedicled flaps (42 cases) and from 6 cm × 4 cm to 25 cm × 8 cm for the free ones (45 cases). Mean flap's size was 48 cm² (range 12-80 cm² ) for the pedicle flaps and 104 cm² (range 24-200 cm² ) for free flaps. In two pedicled cases, a distal congestion was encountered, requiring a second surgery. Debulking procedures were performed in 2 patients. All the patients were successfully treated and no flaps were lost. Mean follow-up period was 8.4 months (range 3-12 months). No range of motion impairment was encountered after surgery and all the patients were able to return to habitual life.

CONCLUSIONS

The present case series highlights the reliability and versatility of perforator flaps for lower extremity defect coverage. Following careful consideration of the etiology, dimensions, location, patient comorbidities, and presence of adequate perforators, a pedicled or free perforator flap can be potentially successful in the most disparate circumstances.

The History and Innovations of Blood Vessel Anastomosis

Surgical technique and technology frequently coevolve. The brief history of blood vessel anastomosis is full of famous names. While the techniques pioneered by these surgeons have been well described, the technology that facilitated their advancements and their inventors deserve recognition. The mass production of laboratory microscopes in the mid-1800s allowed for an explosion of interest in tissue histology. This improved understanding of vascular physiology and thrombosis laid the groundwork for Carrel and Guthrie to report some of the first successful vascular anastomoses. In 1916, McLean discovered heparin. Twenty-four years later, Gordon Murray found that it could prevent thrombosis when performing end-to-end anastomosis. These discoveries paved the way for the first-in-human kidney transplantations. Otolaryngologists Nylen and Holmgren were the first to bring the laboratory microscope into the operating room, but Jacobson was the first to apply these techniques to microvascular anastomosis. His first successful attempt in 1960 and the subsequent development of microsurgical tools allowed for an explosion of interest in microsurgery, and several decades of innovation followed. Today, new advancements promise to make microvascular and vascular surgery faster, cheaper, and safer for patients. The future of surgery will always be inextricably tied to the creativity and vision of its innovators.

Supermicrosurgical treatment for lymphedema: a systematic review and network meta-analysis protocol

BACKGROUND

Lymphedema is a condition that affects up to 130 million subjects worldwide. Since it is related to several complications and a significant reduction in terms of quality of life, it is a heavy burden not only to the patients but also for the healthcare system worldwide. Despite the development of supermicrosurgery, such as vascularized lymph node transfer (VLNT) and lymphovenous anastomosis LVA, the indications and outcomes of these complex groups of interventions remain a controversial topic in the field of reconstructive plastic surgery.

METHODS

This systematic review and network meta-analysis aims to assess the evidence of outcomes of LVA and VLNT in patients with lymphedema. Secondary aims of the project are to determine if for any outcomes, LVA or VLNT is superior to conservative therapy alone, and whether the available evidence favors any kind of supermicrosurgical interventions for lymphedema patients. This study will include original studies of patients with lymphedema on the extremities indexed in PubMed, EMBASE, CENTRAL, PASCAL, FRANCIS, ISTEX, LILACS, CNKI, and IndMED that reported microsurgery (supermicrosurgery) of all techniques aiming the re-functionalization of the lymphatic system. As comparators, mere observation, conservative treatment of any kind, and the other subgroups of supermicrosurgery are planned. The primary outcome of this systematic review and network meta-analysis is the difference of the limb volume, while the secondary outcomes of interest will be erysipelas rates, major and minor complications, postoperative necessity of continuous compression garments, and patient satisfaction, measured by already published and validated scores for quality of life.

DISCUSSION

We will provide an overview and evidence grade analysis of the scientific literature available on the effectiveness of the subcategories of supermicrosurgical interventions for lymphedema.

Are Perforators Reliable as Recipient Arteries in Lower Extremity Reconstruction? Analysis of 423 Free Perforator Flaps

BACKGROUND

Perforator flaps have revolutionized lower limb reconstruction by offering single-stage thin, pliable coverage with an excellent aesthetic match. Although anastomosis of the flap to a major artery remains the gold standard, perforator-to-perforator anastomosis has several advantages, including expedient recipient dissection and increased recipient options in vessel-depleted extremities. The aim of this study was to compare flap survival when a perforator or major artery was used as a recipient vessel.

METHODS

A retrospective cohort of free perforator flaps for lower limb reconstruction was reviewed. Demographics, comorbidities, vascular status, defect characteristics, operative details, and complications were recorded. Outcomes for perforator and major artery recipients were compared.

RESULTS

Four hundred twenty-three flaps were performed for various reasons using perforator flaps. The total limb salvage rate was 98.8 percent. Total and partial flap failure rates were 6.1 percent and 9.0 percent, respectively. Comparing perforator recipients [n = 109 (25.8 percent)] to major artery recipients [n = 314 (74.2 percent)], there was no significant difference in total (p = 0.746) or partial flap failure (p = 0.212). Significant factors between the groups included larger flap size with major artery recipients (p = 0.001) and shorter operative time when using a perforator recipient (p = 0.012).

CONCLUSIONS

Perforator-to-perforator anastomosis is a reliable option that affords equivalent rates of flap success compared to major artery anastomosis in lower extremity reconstruction. The authors advocate using a major artery recipient in defects where the axial vessels are easily accessible. A perforator recipient is a viable alternative in defects where access to the axial vessels is inconvenient and in patients with limited recipient options.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Recent Advances in Ultrasound Technology: Ultra-High Frequency Ultrasound for Reconstructive Supermicrosurgery

BACKGROUND

 Currently, microsurgeons are in the era of supermicrosurgery and perforator flap reconstruction. As these reconstructions frequently utilize vessels that are smaller than a single millimeter, understanding of location of lymphatic vessels and perforator anatomy preoperatively is essential. To change with the times, the role of ultrasound has changed from just an adjunct to primary imaging of the choice in reconstructive supermicrosurgery. Recently, a novel ultrasonographic technique involving the use of ultra-high frequency ultrasound (UHFUS) frequencies has entered the scene, and appears a promising tool in surgical planning.

METHODS

 The literatures on the applications of UHFUS in reconstructive supermicrosurgery were retrieved and reviewed from more than 60 literatures have been published on the surgical applications of UHFUS.

RESULTS

 Nine studies were retrieved from the literature on the applications of UHFUS in reconstructive supermicrosurgery. The articles report both application for lymphatic surgery and perforator flaps.

CONCLUSIONS

 UHFUS application involves an increasing number of reconstructive supermicrosurgery field. UHFUS is a valuable and powerful tool for any reconstructive surgeons who are interested in performing supermicrosurgery.

Supermicrosurgical lymphovenous anastomosis for the treatment of recurrent cellulitis-associated lymphedema in the lower limb

Recurrent leg cellulitis can damage the lymphatic system and result in chronic lymphedema. Antibiotic therapy is administered to prevent cellulitis; however, antibiotic-resistant bacteria frequently occur. Supermicrosurgical lymphovenous anastomosis (LVA) can play a role in stopping the vicious circle by improving lymph circulation. In the present report, we have described the case of a 40-year-old male patient with frequent cellulitis and subsequent left leg edema. Based on the lymphoscintigraphy findings, LVA was performed on the left leg (six anastomoses). One year later, the lymphedema had subsided without further cellulitis. Lymphoscintigraphy revealed no dermal backflow. Thus, LVA is a treatment option for recurrent cellulitis-associated lymphedema.

Posterior auricular artery helix root free flap-part II: clinical application

The surgical repair of full-thickness defects involving the alae nasi is complex. Pedicle flaps such as frontal and nasolabial flaps can be used, but require several interventions with different techniques. In contrast, free flaps from the foot of the ear helix allow the three layers of the nasal wings to be reconstructed in a single operation. Nevertheless, in the classical approach, the vascular pedicle is short. Although some authors have proposed raising the flap in a retrograde manner, this still yields a relatively short pedicle with narrow vessels. In the companion paper, we demonstrated that a posterior auricular artery helix root free flap (PAAHF) can be harvested from the posterior auricular vessels, thus increasing the useful pedicle length. The case of a patient with basal cell carcinoma of the left ala is presented here. A right helix root free flap was anastomosed with the facial vessels at the left mandibular notch. This new flap overcomes the main limitation of the classical helix root flap, namely the length of the pedicle. It has all of the morphological qualities of the classical flap, but with simpler vascular assembly, since autologous venous grafts and complex anastomoses are not required.

Neovascularization of engineered tissues for clinical translation: Where we are, where we should be?

One of the key challenges in engineering three-dimensional tissue constructs is the development of a mature microvascular network capable of supplying sufficient oxygen and nutrients to the tissue. Recent angiogenic therapeutic strategies have focused on vascularization of the constructed tissue, and its integration in vitro; these strategies typically combine regenerative cells, growth factors (GFs) with custom-designed biomaterials. However, the field needs to progress in the clinical translation of tissue engineering strategies. The article first presents a detailed description of the steps in neovascularization and the roles of extracellular matrix elements such as GFs in angiogenesis. It then delves into decellularization, cell, and GF-based strategies employed thus far for therapeutic angiogenesis, with a particularly detailed examination of different methods by which GFs are delivered in biomaterial scaffolds. Finally, interdisciplinary approaches involving advancement in biomaterials science and current state of technological development in fabrication techniques are critically evaluated, and a list of remaining challenges is presented that need to be solved for successful translation to the clinics.

Femoral artery-nourished anteromedial thigh flap: A new perspective in oral and maxillofacial defect reconstruction

OBJECTIVES

The aim of this study was to evaluate the feasibility and efficacy of the femoral artery (FA)-nourished anteromedial thigh (AMT) flap for reconstructing oral and maxillofacial defects.

PATIENTS AND METHODS

The authors analyzed a retrospective case series of 13 patients who underwent the reconstruction of oral and maxillofacial defects with the FA-nourished AMT flap. The flap design and the methods for defect reconstruction are described, and the reconstructive efficacy is reported.

RESULTS

Of the 13 patients, 12 were men, and 1 was woman, with an average age of 52.2 years. Of these FA-supplied AMT flaps, 7 were singly used, 5 were combined with the anterolateral thigh (ALT) flap or its chimeric flaps, and 1 was separately used with the ALT flap. Postoperatively, all flaps survived completely, without vascular compromise or major wound complications.

CONCLUSIONS

The FA-nourished AMT flap can also be used to reconstruct some common oral and maxillofacial defects, especially as a new alternative to the ALT flap. In addition, this flap can be combined with the ALT flap or its chimeric flaps or separately used with the ALT flap for the reconstruction of complex defects.

Application of the "Open-Y" technique in recipient perforator vessels: A comparison study between "Open-Y" and conventional end-to-end anastomosis in terms of postoperative complications

BACKGROUND

Over the last few years, the increasing employment of perforators as both donor and recipient vessels for free flap tissue transfer lead the surgeons to perform increasingly smaller anastomosis. Size discrepancy is a common problem that might affect the patency rate. This has many implications in the outcome of the procedure and the "Open-Y" technique might be useful to perform an easier anastomosis by using a bifurcation area.

PATIENTS AND METHODS

Between April 2018 and April 2020 a total of 98 patients who received a free tissue transfer reconstruction throughout the body were retrospectively recruited. The "Open-Y" technique of anastomosis was used in the recipient artery of 40 perforator-based flaps, while in 58 cases a conventional anastomosis with nonperforator vessel was performed. The size discrepancy rate and the arterial anastomotic site-related complications were evaluated and compared.

RESULTS

The flap success rate was 100% (40/40) in the "Open-Y" group, slightly better than the conventional group (96.5%; 56/58) despite a higher size discrepancy rate in the "Open-Y" group (27.5%; 11/40) compared to the conventional one (12%; 7/58) (p value, .053). The rate of complications was different, too. Better results were obtained in the "Open-Y" group with 4/40 (10%) complications compared to the 18/58 (31%) of the conventional group (p value, .013).

CONCLUSIONS

The "Open-Y" technique is a simple and interesting procedure to increase the vessels' diameter thus reducing size discrepancy and increasing the reliability of the anastomosis. This is extremely valuable in the perforator-to-perforator free tissue transfer setting where surgeons are often forced to work in a supermicrosurgical field. Every time a suitable bifurcation is encountered this might be a useful procedure to increase the end-surface available for the anastomosis or to reduce vessels size discrepancy.

Supermicrosurgery in Lower Extremity Reconstruction

Supermicrosurgery is defined as microsurgery working on vessels less than 0.8 mm, allowing applications in smaller-dimension microsurgery, such as lymphedema, minimal invasive reconstruction, small parts replantation, and application of perforator as recipient. To accommodate this technique, developments and use of finer instruments, smaller sutures, new diagnostic tools, and higher-magnification microscopes have been made. Although supermicrosurgery has evolved naturally from microsurgery, it has developed into a unique field based on different thinking and tools to solve problems that once were difficult to solve.

Advancements in Reconstructive Surgery Broaden Opportunities for Salvage of the Injured Lower Extremity

Advancements in microsurgery have made lower extremity reconstruction possible even after major soft tissue loss or tibial nerve disruption. There is an ongoing paradigm shift in the indications for amputation versus salvage and in flap selection protocols for different areas of the lower extremity. Initial evaluation, patient selection, triage, and timing of reconstruction are essential factors that can influence functional and aesthetic outcomes. The emergence of perforator flaps and the application of new concepts such as free-style flaps, propeller perforator flaps, thinning of free flaps, and supermicrosurgery have provided reconstructive surgeons with many techniques to decrease donor-site morbidity and improve outcomes. This includes options for reconstruction on extremities with single or no adequate runoff vessels. We present a review of the major advancements in reconstructive surgery for salvage of the traumatic lower extremity.

Characteristics of the Superficial Circumflex Iliac Artery Perforator Flap in a Western Population and a Practice Approach for Free Flap Reconstruction

BACKGROUND

 There has been increasing interest in the superficial circumflex iliac artery perforator (SCIP) flap as a source of thin, pliable soft tissue combined with a favorable donor site. Despite several clinical series from Asia, barriers to adoption include reluctance to perform submillimeter "supermicrosurgery" and the effect of body habitus on flap feasibility. The purpose of this study is to distinguish vascular anatomic characteristics of the SCIP flap in a North American population.

METHODS

 Computed tomography angiography was examined in 84 flaps in healthy prospective renal donor patients from a radiographic database. Descriptive statistics as well as linear regression comparing variables to body mass index (BMI) were performed.

RESULTS

 Mean BMI was 27.1 ± 3.5 kg/m², while the mean patient age was 47.8 ± 11.4 years. The superficial circumflex iliac artery (SCIA) originated from the common femoral artery in 92% cases, with remainder originating from the profunda femoris. The mean vessel diameter was 1.85 mm at source vessel origin. Distance from skin to source vessel averaged 30.7 mm. Suprascarpal subcutaneous thickness averaged 16.5 mm. The mean distance from Scarpa's fascia to vessel origin was 14.1 mm. Direct three-dimensional distance from vessel origin to pubic tubercle was 50.2 mm. A medial and lateral perforator split off of the SCIA was observed in 38 cases (45%). Significant differences were shown when comparing BMI to skin to source vessel distance (p < 0.001), suprascarpal subcutaneous fat thickness (p < 0.001), and fascial distance to vessel origin (p < 0.001). BMI did not significantly affect vessel diameter.

CONCLUSION

 Despite a significantly higher BMI than many previously published cohorts, the SCIP remains an excellent source of thin and pliable tissue. When dissected closer to the source vessel, a vessel caliber of nearly 2 mm can be achieved, which may obviate the need for "supermicrosurgery" in this population.

The Application of a Jigsaw Puzzle Flap Based on a Freestyle Perforator and an Aesthetic Unit for Large Facial Defects

BACKGROUND

The single-stage reconstruction of large facial defects remains a conundrum due to the balance between function and aesthetics after skin cancer radical resection.

OBJECTIVE

The goal of this study was to explore a novel surgical procedure for large facial defects that not only resurfaces the large defect in single stage but also improves aesthetic outcomes for both defects and donor sites.

METHODS

The reconstructions were performed using local flaps in the form of a "jigsaw puzzle" flap based on a freestyle perforator and facial aesthetic unit. This procedure starts with a Doppler signal of the perforator and proceeds sequentially in conjunction with adjacent flaps, similar to fitting puzzle pieces, to create a new, large, jigsaw puzzle-like flap that complies with the concept of a facial aesthetic unit. All defects achieved tensionless primary closure with suturing in a concealed area.

RESULTS

Procedures were performed for 40 patients; the average size of the defects was 37 cm (range, 6-51 cm). The patients were followed up for a range of 6 months to 2 years, and reconstruction without flap loss was 100% successful.

CONCLUSION

Via a jigsaw puzzle flap based on a freestyle perforator and an aesthetic unit, we can take advantage of a greater freedom of flap selection and have a more versatile aesthetic design. The jigsaw puzzle flap concept represents a safe and favorable approach to the reconstruction of large facial defects.

Microscopic Thyroidectomy: A Prudent Option

Microscopic Thyroidectomy is not a new surgical technique but it is not explored much. The routine use of microscope in thyroid surgery can reduce the rate of nerve palsy and hypocalcemia. Nine cases were done exclusively with the microscope only and postoperative nerve palsy and hypocalcemia were noted. We have also discussed about optimum working distances and magnification for critical structures during thyroid surgery. No patient has any nerve palsy while one patient reported transient hypocalcemia. Recurrent laryngeal nerve could be identified at 2 × but optimal magnification for dissection of nerve should be 4 ×. We find this technique easy to adopt and critical structures can be identified and preserved easily with microscopic thyroidectomy then conventional and loupe technique. It is better to have standardized and optimum working distance and magnification during different steps of surgery. It is great teaching tool in view of its better illumination and magnification.

Penile Reinnervation Surgery: A Comprehensive Review of the Literature

BACKGROUND

Modern approaches to erectile dysfunction (ED) often entail the use of multimodal medical therapy and surgery; however, with recent advances in microsurgery, new options may exist for patients suffering from ED. This comprehensive review of the literature serves to reevaluate anatomical and physiological principles that mediate erection to improve understanding for reconstructive surgeons hoping to offer new interventions.

METHODS

A search strategy for this review was agreed upon by all authors. Articles were divided into 2 categories - primary and secondary. Primary articles were defined as those in which the anatomy of the pelvis and/or perineum was the primary focus of the article, whereas secondary did not directly focus on anatomic considerations. Select historical texts and textbook chapters were also included to provide well established and critical anatomical evidence for this review.

RESULTS

Several approaches may be used to restore nerve function to treat neurogenic and vasculogenic ED. Somatic sensory loss can be treated by either direct neurorrhaphy or neuroplasty in the location of disruption. Microvascular techniques also exist to improve flow or to repair small vessels injured in the pelvis. Classical approaches to impotence include vein stripping to reduce venous outflow or direct vascularization to improve inflow.

CONCLUSIONS

Postradical prostatectomy ED has been demonstrated to improve with microsurgical interventions. In the coming years, innovation will continue and collaboration between plastic surgeons and urologists will allow us to tackle this common and difficult problem.

Can Smartphones Be Used to Perform Video-Assisted Microanastomosis? An Experimental Study

BACKGROUND

Smartphone cameras are continuously improving. The present study aimed to evaluate the possibility of using smartphones' magnification system to perform microanastomosis in rats.

METHODS

Fifteen rats were randomly divided into 3 groups, according to the magnification system used: Microscope, iPhone 7 smartphone, and Galaxy S7 smartphone. In the microscope group, a DFVasconcelos microsurgery microscope was used. In both smartphone groups, the magnifications systems were connected to a 55-inch television through the mirror function. Animals in both groups underwent femoral artery anastomosis in the right forepaw and femoral nerve neurorrhaphy in the left hindleg. The body weight, arterial and nerve caliber, and anastomosis time and patency were immediately analyzed.

RESULTS

No significant differences were observed between the groups regarding body weight, arterial, or nerve caliber. The smartphones did not provide a sufficient quality of image for an adequate identification of the arterial walls. Therefore, neither arterial anastomosis nor neurorrhaphy could be completed, even after 3 hours of surgery. The first steps toward anastomosis or raffia were performed with difficulty.

CONCLUSION

The current video resolution and lack of stereoscopic image of available smartphones is not sufficient to perform video-assisted anastomosis of femoral arteries or nerves.

Phalloplasty Following Penectomy for Fournier's Gangrene at a Tertiary Care Center

Treatment of Fournier's gangrene often requires extensive surgical debridements that can ultimately necessitate penile amputation. Reconstruction can be challenging as these patients tend to have medical comorbidities deeming them poor microsurgical candidates. Fournier's gangrene resulting in penectomy is an infrequent occurrence, and treatment with phalloplasty is rarely described in the literature. Herein, we present a case of a 60-year-old male with poorly controlled diabetes mellitus who developed Fournier's gangrene in July 2017. His treatment course included multiple surgical debridements without resolution, eventually necessitating a penectomy. The patient elected for surgical reconstruction and underwent a phalloplasty procedure utilizing a radial forearm free flap. This case demonstrates a rare case of Fournier's gangrene resulting in penectomy with a unique reconstruction utilizing a radial forearm free flap in a poor microsurgical candidate.

WITHDRAWN: The use of integrated indocyanine green fluorescence microscope camera for intraoperative lymphography of supermicrosurgery

Ahead of Print article withdrawn by publisher.

Introducing the subdermal free flap: Preserving the ultrathin-free skin flap option in morbidly obese patients

In the morbidly obese population (BMI > 35), distal extremity defects are difficult to reconstruct. Traditional skin flaps are several centimeters in thickness in obese patients; however, a new plane superficial to the scarpal plane has demonstrated success in these patients. In this report, we present a 62-year-old female (BMI = 44.81) with a chronic lower extremity wound. A suprascarpal thin flap (approximately 1 cm in thickness) was harvested from the thigh and transferred successfully with no wound-healing issues.