The effects of two different delay phenomena in flow-through venous flaps

The purpose of this study was to investigate the effects of two different types of pedicle manipulation two weeks prior to harvesting of flow-through venous flaps (FTVF). The dorsal aspect of the ear of New Zealand white rabbits was used in the investigation. Two different delay procedures (manipulation of pedicle) were performed and compared to the single stage harvesting of FTVF. In the first delay (arterial ligation group), the central artery was ligated at the proximal and distal edge of the flap, and the flap was harvested after two weeks. In the second delay (arteriovenous shunt group), the central artery was anastomosed to the lateral caudal vein at the proximal part of the ear to create an arteriovenous shunt and to increase blood flow in the venous system. The FTVF was again harvested two weeks after the creation of the arteriovenous shunt. The survival rates and the superficial flap necrosis rates of the two different delay groups were compared to the nondelayed group.The mean survival of the arterial ligation group (82%) and the arteriovenous shunt group (80%) show significantly increased survival when compared to the nondelayed group (44%). The superficial flap necrosis rates in the two delay groups were also decreased when compared to the non delayed group.     

Effects of methylprednisolone on the viability of experimental flow-through venous flaps

In this study, the effects of a corticosteroid, methylprednisolone, on the survival of flow-through venous flaps were investigated in rabbits. Flow-through venous flaps, sized 3.0 x 4.5 cm, were raised in the rabbit-ear model. Animals were randomly distributed into three groups, and 30 flaps were raised as follows: Group 1 (n=10): control flow-through venous flaps (intramuscular saline injection 2 ml/d); Group 2 (n=10): flow-through venous flaps with daily intramuscular methylprednisolone injection (30 mg/kg/d); and Group 3 (n=10): negative control composite grafts with the flow-through vein ligated at both edges of the flap. All injections were done 24 hr and 1 hr preoperatively, and for 5 days postoperatively. Observations included gross and histologic examination, and percentage of survival of the flaps on the tenth day. Venous flaps of the animals receiving daily methylprednisolone injections (Group 2) were noted to have statistically significantly improved flap survival ( p<0.05), compared to the control group (Group 1). Flaps in Groups 1 and 2 demonstrated significantly higher survival rates, compared to the composite grafts ( p<0.01). Histologic examination of methylprednisolone-treated animals showed normal stratified squamous epithelium, while complete necrosis was noted in the composite grafts. Untreated flow-through venous flaps demonstrated patchy epidermal sloughing, crusting, and partial necrosis. These results suggest that the survival of potentially ischemic flow-through venous flaps can be enhanced in rabbits by daily methylprednisolone treatment in the perioperative period. Increased tolerance to ischemia and modulation of venous flap microcirculation might be possible mechanisms for this salutary effect.     

Pedicled free flaps: indications in complex reconstruction

Pedicled free flaps are indicated when distant composite tissue is required for wound coverage and adjacent recipient vasculature is unsuitable for microvascular anastomosis. Carrier vessels from a noninjured extremity temporarily nourish the flap while neovascularization between the wound bed and the flap occurs. This process is augmented by intermittent occlusion of the vascular pedicle to prepare the flap for pedicle division. Rigid immobilization must be maintained to prevent avulsion of the flap. Laser Doppler monitoring of the flap during the ischemic training period permits division of the pedicle with confidence. This technique permits transfer of large flaps to compromised wounds with the advantage that the microvascular anastomoses can be performed safely away from the zone of injury. Provided immobilization can be maintained, flaps based on either a lower extremity or wrist carrier can reach virtually any area of the body.     

Subcutaneous tissue flaps: theoretical principles and clinical applications

The paper examines the anatomical principles and clinical applications of subcutaneous tissue flaps. This tissue, located between the dermis and muscular aponeurosis, is an anatomical entity supplied by a well-developed vascular network. Two examples of the application of the principles of the de-epithelialized ”turn-over” flaps in the hand and leg are presented. The reasons for their use and their advantages are briefly discussed. Received: 29 September 1998 / Accepted: 7 September 1999     

Microcirculation study of rabbit ear arterial and venous flow-through flaps using a window chamber model

Venous flaps are used widely for finger reconstruction because they provide thin tissue, and the flap harvest is associated with less donor-site morbidity. The viability of the venous flap, however, is not as good as that of the ordinary perfused skin flap, and its microcirculation is questionable according to various indirect observations and hypotheses in the literature. Using a window chamber model in a rabbit ear, both arterial and venous flow-through flaps were studied. Factors evaluated were flap viability, flap weight, flap circulation as assessed by laser Doppler flowmetry, and direct observation of the microcirculation. Statistical analysis was performed using the two-sample t test. There was no statistically significant difference in viability between arterial and venous flow-through flaps (p = 0.661). The arterial flow-through flap had better perfusion than thevenous flow-through flap, as measured by laser Doppler perfusion studies (10.40 perfusion units [PU] vs 4.50 PU). However, no statistically significant difference was noted (p = 0.0717). Flap weight assesseed 1 week after surgery and oxygen saturation measured immediately after surgery showed significant differences between the arterial and venous flow-through flaps (p = 0.0001 and 0.0279). These datasuggest that the arterial flow-through flap is subjected to more congestion becauseof the abnormal flow pattern seen, andpossibly because of a superior inflow or nutritional status found in these flaps. Using vital microscopy, direct evaluation of the microcirculation was performed. A to-and-fro phenomenon was noted in both arterial and venous flow-through flaps,which was followed by a reversed direction of flow in part of the microvasculature. With both types of flaps, the blood was directed eventually from the postcapillary venules to the capillaries, through the terminal arterioles, and then to the arterioles. These findings may be explained partially by the normal physiologic pressure gradients present in the microvasculature of these flaps. In this study, direct observation of the microcirculation was used as well as other objective measures to determine the flow patterns and clinical behaviors found in these types of flaps. A model in a rabbit ear for the study of venous and arterial flow-through flaps is described, and clinical correlations are discussed.     

Effect of topical nitroglycerine on the survival of ischemic flow-through venous flaps in rabbits

The purpose of this study was to investigate the effect of transdermal nitroglycerin on the survival of an ischemic one-vein flow-through venous flap (FTVF) model in the rabbit ear. Fifteen New Zealand white male rabbits were randomly divided into three groups: Group 1 (n = 5, 10 flaps)- no dressing on the operative wound; Group 2 (n = 5, 10 flaps)-occlusive film dressing group [polyurethane semipermeable membrane (Op-Site)]; and Group 3 (n = 5, 10 flaps)- transdermal nitroglycerine pad (Novartis-Nitroderm TTS 5 mg) on the wound. Nitroderm TTS and the occlusive film dressing were changed daily postoperatively for 3 days. The percentage of the surviving area and the mean extent of the surviving area to the axial vein were calculated on the postoperative 14 (th) day. Necrotic and surviving areas of flaps were consistent with histopathologic findings. Group 3 (83 percent +/-10.46, 17.4 +/- 3.0 mm) had larger flap surviving areas and longer distances to the axial vein than Group 1 (60 percent +/-15.29, 11.8 +/- 4.3 mm) and Group 2 (58 percent +/-10.25, 12.8 +/- 2.8 mm). The difference was statistically significant ( p < 0.05). This study demonstrated that postoperatively applied transdermal nitroglycerine significantly increased the ischemic FTVF survival area and the survival width to the axial vein.     

Arterialized venous flow-through flaps in the reconstruction of digital defects: case series and review of the literature

BackgroundArterialized venous flow-through (AVFT) flaps are useful in reconstructing small soft tissue defects. Currently, no guidelines exist for the use of AVFT flaps for reconstructing soft tissue defects in the digits of the hand. We retrospectively reviewed our experience with AVFT flaps and developed a selection process for vascular anastomoses.MethodsWe reviewed the use of AVFT flaps in a series of ten consecutive patients requiring reconstruction of small soft tissue defects of the fingers.ResultsBetween 2006 and 2012, ten consecutive digital reconstructions were performed using AVFT flaps. Flap sizes ranged from 5 to 13.5 cm². Initial congestion was seen in all flaps and resolved within 3–7 days. Leeches were utilized in two cases. All cases achieved good functional results. Three illustrative cases from our series of ten are presented, each demonstrating key decision-making factors in selecting recipient and flap vessels for anastomosis.ConclusionsAVFT flaps appear congested post-operatively, resolving in days to weeks, and resulting in healthy coverage of digital soft tissue defects with good functionality. We suggest a selection process for the use of AVFT flaps in digital soft tissue reconstruction, based on dorsal vs. volar and proximal vs. distal defect location, and the flap’s inherent venous architecture.     

上斜方肌、肩胛冈骨肌皮瓣的解剖研究与临床应用

目的：进一步探讨以颈横血管为蒂的上斜方肌肌皮瓣及肩胛冈骨肌皮瓣的应用解剖学基础,及其在口腔颌面缺损修复中的应用。方法：解剖观测32例上斜方肌、肩胛冈的形态和血供,并应用5例该组织瓣修复口腔颌面部缺损。结果：①上斜方肌近似于梯形,平均高度上、下、内、外四缘分别为174．63、157．18、86．98和80．95mm,面积126．78cm^2;肩钾冈全长131．21mm。②颈横动脉干、颈浅动脉干及其升支、肩胛冈支长度分别为42．50、27．80、43．12和28．75mm。升支发出0．5mm以上肌皮穿支3－6支;回流静脉与相应动脉伴行。③临床应用5例,均获成功。结论：以颈横血管为蒂的上斜方肌肌皮瓣及肩胛冈骨肌皮瓣血管蒂长、手术易操作,且可带肩胛冈修复,适合于修复口腔颌面部缺损。     

Clinical applications of venous flaps in the reconstruction of hands and fingers

In recent years, the venous flap has been highly regarded in microsurgical and reconstructive surgeries, especially in the reconstruction of hand and digit injuries. It is easily designed and harvested with good quality. It is thin and pliable, without the need of sacrificing a major artery at the donor site, and has no limitation on the donor site. It can be transferred not only as a pure skin flap, but also as a composite flap including tendons and nerves as well as vein grafts. All these advantages make it an optimal candidate for hand and digit reconstruction when conventional flaps are limited or unavailable. In this article, we review its classifications and the selection of donor sites, update its clinical applications, and summarize its indications for all types of venous flaps in hand and digit reconstruction.     

Propeller perforator flaps in distal lower leg: evolution and clinical applications

Simple or complex defects in the lower leg, and especially in its distal third, continue to be a challenging task for reconstructive surgeons. A variety of flaps were used in the attempt to achieve excellence in form and function. After a long evolution of the reconstructive methods, including random pattern flaps, axial pattern flaps, musculocutaneous flaps and fasciocutaneous flaps, the reappraisal of the works of Manchot and Salmon by Taylor and Palmer opened the era of perforator flaps. This era began in 1989, when Koshima and Soeda, and separately Kroll and Rosenfield described the first applications of such flaps. Perforator flaps, whether free or pedicled, gained a high popularity due to their main advantages: decreasing donor-site morbidity and improving aesthetic outcome. The use as local perforator flaps in lower leg was possible due to a better understanding of the cutaneous circulation, leg vascular anatomy, angiosome and perforasome concepts, as well as innovations in flaps design. This review will describe the evolution, anatomy, flap design, and technique of the main distally pedicled propeller perforator flaps used in the reconstruction of defects in the distal third of the lower leg and foot.     

The Doppler probe for planning flaps: anatomical study and clinical applications

The Doppler probe was used to identify the dominant cutaneous perforating arteries in a series of 10 patients. The results were compared with our previous total body fresh cadaver anatomical studies and a close correlation was found. The instrument was used in a series of patients to plan the base, the axis and the dimensions of skin flaps for local, distant and free transfer. A dominant perforator was located at the base of the flap, the surrounding skin was scanned to identify the next dominant perforator in each direction and the appropriate axis was chosen by drawing a line between two nominated perforators. Often the flap was based distally or its axis departed from the main course of the supplying vessel. The technique proved to be simple and reliable and in many cases flaps of unusual dimensions and directions were transferred successfully. The instrument provides a useful link between the anatomical dissecting room and the operating theatre.     

Pedicled perforator flaps in breast reconstruction: a new concept.

INTRODUCTION: Pedicled perforator flaps have not been widely described for the breast. The aim of this study is to report our clinical experience with pedicled perforator flaps in breast reconstruction. MATERIAL AND METHODS: Between May 2000 and May 2003, pedicled perforator flaps were used in 31 patients. The indications were immediate partial breast reconstruction and thoracic reconstruction for carcinomatous mastitis or tumour recurrence. Perforators were identified by Doppler preoperatively. The Doppler-located thoracodorsal artery perforator (TDAP) or another perforator such as the intercostal artery perforator (ICAP) was looked for. If the perforators had good calibers, the flaps were then based solely on these perforators. If the perforators were tiny but pulsating, the TDAP flap was harvested as a muscle-sparing latissimus dorsi type I (MS-LD I) with a small piece of muscle (4x2 cm) included to protect the perforators. If the perforators were not-pulsating, a larger segment of the LD muscle was incorporated to include the maximum of perforators (MS-LD II flap). The nerve that innervates the rest of the LD muscle was always spared. If most of the LD was included in the flap, the flap was then classified as MS-LD III. RESULTS: The mean flap dimensions were 20x8 cm. Using this algorithm, the TDAP flap was harvested in 18 cases and the ICAP flap in three cases. In addition, there were 10 MS-LD flaps with a variable amount of muscle. In addition, one parascapular flap was dissected. A successful flap transfer was achieved in all but three patients, in whom limited partial necrosis occurred. Seroma was not encountered at the donor sites of the perforator flaps (0%) compared to four (40%) after a MS-LD flap. CONCLUSION: Our results show that pedicled perforator flaps are additional options for breast surgery and that they may be used whenever an adequate perforator can be found. This technique is safe and reliable if the algorithm described is used when choosing a flap.     

Four types of venous flaps for wound coverage: a clinical appraisal

Venous flaps were used for coverage of hand wounds over exposed bones, joints, and tendons in 28 patients. Four types of operations were performed. Among them type IV was the best. It included the advantages of perfusion in types I and III, but excluded their disadvantages. The viability of venous flaps was confirmed. Clinical observation showed that a venous flap is not merely a composite graft. The presence of a vascular network in the flap helps to ensure initial survival before the establishment of neovascularization between the venous flap and the recipient site. Partial loss of a flap was observed in two cases and complete failure was seen in one case. Viability versus flap size and modality of perfusion are analyzed. With total venous perfusion, small venous flaps usually survive better than large ones. For large venous flaps, arterialized venous perfusion is better than total venous perfusion. Venous flaps are useful for wound coverage of fingers and hand, but they do not replace cross-finger flaps or other conventional flaps when these simpler flaps are available.     

Pedicled flaps in the treatment of nonhealing perineal wounds

INTRODUCTION: A persistent sinus is an annoying complication following proctectomy. We examined the experience of a single colorectal surgeon in treating this condition using pedicled flaps. METHODS: Case note review of all patients undergoing gracilis muscle transposition, Rectus abdominis muscle flap or omental flap for persistent perineal sinus. RESULTS: Seventeen patients were identified: seven had gracilis muscle transposition, eight had omental transposition and two had a rectus abdominis flap. 13/17 patients who underwent a flap had a persistent sinus following proctectomy for Inflammatory bowel disease. Four patients who had a gracilis muscle transposition achieved healing. Seven out of eight patients had good results with omental transposition. One patient did well after a rectus abdominis flap. CONCLUSIONS: A gracilis transposition is a relatively simple operation with minimal morbidity useful for superficial sinuses not requiring a muscle bulk. A rectus abdominis flap is a more complex specialized procedure with better results especially in dealing with larger cavities but it may compromise future stoma sites. Omentoplasty has excellent results, but is only available in some patients.     

Reactive oxygen species in experimental ischemic flow-through venous flaps and effects of antioxidants on reactive oxygen species and flap survival

We made an experimental study on rabbit ears using an ischemic flow-through venous flap model to determine the changes in levels of reactive oxygen species (ROS) in venous flaps and effects of exogenous antioxidants on endogenous antioxidant superoxide dismutase (SOD) and ROS indicator malonyldialdehyde (MDA) levels and on flap survival. Mean SOD level significantly decreased and the MDA level significantly increased after the flap elevation according to basal levels of untreated flaps. The mean flap survival rates in the exogenous SOD or glutathione (GSH)-treated groups were significantly increased with respect to the untreated group. The SOD level was increased significantly and the MDA level was decreased significantly in the SOD- or GSH-treated groups relative to the control group after the flap elevation. These results have suggested that ROS may have an important role in ischemic flow-through venous flap pathogenesis and additionally, antioxidants could enhance the rate of flap survival.