Skin-fold advancement flaps for closing large proximal limb and trunk defects in dogs and cats

OBJECTIVE: To describe the use of skin-fold advancement flaps for covering large skin defects in dogs and cats. STUDY DESIGN: Clinical study. ANIMALS: Eight client-owned animals: 6 dogs and 2 cats. METHODS: Six dogs and 2 cats underwent reconstruction of soft-tissue wounds resulting from traumatic, neoplastic, or infectious lesions. Skin-fold flaps were created by division of the medial and lateral attachment to the proximal limb or the dorsal and ventral attachment to the trunk, enabling closure of adjacent defects on the trunk or proximal limb, respectively. RESULTS: Skin-fold flaps proved effective for closing defects in all animals. Necrosis of a portion of the flap occurred in 2 dogs due to technical errors, but the resultant defects remained amenable to primary closure. All wounds ultimately healed primarily, without major complications. CONCLUSION AND CLINICAL RELEVANCE: The skin-fold advancement flap is a versatile technique that lends itself to use in a variety of locations, depending on which attachments are divided. The clinical results are comparable with those reported for axial pattern and subdermal plexus flaps.     

Investigation and clinical application of a novel axial pattern flap for nasal and facial reconstruction in the dog

OBJECTIVE: To describe the vascular supply to a facial skin flap based at the commissure of the lip in the dog and report on its use in four dogs. STUDY DESIGN: Experimental and prospective clinical study. Animals Five canine cadavers and four client-owned dogs. METHODS: In the cadavers, the ventral aspect of the zygomatic arch, the ventral margin of the caudal mandible and the wing of the atlas were marked as anatomical boundaries of a skin flap that was elevated from the subcutaneous tissues to the level of the medial canthus of the eye. Methylene blue dye and barium sulphate solution were independently infused through a common carotid (three dogs) or facial artery (two dogs) catheter. Distribution of dye throughout the harvested skin was assessed subjectively. After contrast infusion the flap was excised and radiographed. The technique was used to reconstruct large facial or nasal defects in four dogs after tumour or skin lesion excision. RESULTS: Cadaver dissections and contrast studies clearly demonstrated three direct cutaneous arteries, the superior and inferior labial arteries and the angularis oris artery, arborising within the base of the flap. A separate direct cutaneous branch of the angularis oris artery was identified. An arterial plexus was identified within the distal flap, within which this artery communicates with the transverse facial artery and a cutaneous branch of the masseteric artery. Dye infusion caused discolouration of the elevated skin and vasculature within the flap. The flap survived in all clinical cases with marginal distal necrosis in one dog. CONCLUSIONS: The complex facial flap described is perfused by three direct cutaneous arteries and functions reliably in clinical cases.     

Axial pattern flap based on the lateral caudal arteries of the tail in the dog: an experimental study

OBJECTIVE: To determine applicability and size limits of an axial pattern flap based on the lateral caudal arteries in dogs to reconstruct caudodorsal trunk skin defects. STUDY DESIGN: Experimental study. ANIMALS: Ten mature, mixed breed dogs. METHODS: The lateral caudal vessels of the tail were incorporated in the flaps of the treatment group (n=5) and were ligated in the control group (n=5). Flaps were rotated and placed into experimentally created caudodorsal skin defects on the trunk. The length and area of tissue that remained viable in each flap were determined. RESULTS: Mean (+/-SD) survival area (222.8+/-32.9 cm2) and length (25.1+/-4.5 cm) of vascularized flaps were significantly greater (P<.05) compared with control flaps (94.9+/-13.4 cm2 and 14.61+/-4.7 cm). Necrosis occurred in all control flaps, resulting in lower percentage flap area (48.8%) and length (47.1%) survival compared with vascularized flaps (78.1%, 77.5%). CONCLUSIONS: Axial pattern flap based on lateral caudal arteries of the tail was successfully elevated and transferred in a single procedure, with 78% survival for closure of large experimentally created caudodorsal trunk defects in dogs. CLINICAL RELEVANCE: Large cutaneous defects of the caudodorsal trunk area in dog could be reconstructed with tail axial pattern flap. Limitations in terms of size and changes in animal appearance have to be considered before flap elevation.     

Use of the scrotum as a transposition flap for closure of surgical wounds in three dogs

OBJECTIVE: To describe use of the scrotum as a pedicle flap to cover defects created by tumor excision in the perineum or caudal and medial aspect of the thigh. STUDY DESIGN: Clinical study. ANIMALS: Three dogs. METHODS: After tumor excision and prescrotal castration, an incision was made around the base of the scrotum, leaving a pedicle on the side opposite the skin defect. After removal of the tunica dartos and abdominal fascia, the scrotal skin was stretched and shaped to the defect, then sutured in position with a simple interrupted pattern. Bandages that were changed every 48 hours compressed the flaps, and healing was observed until sutures were removed. RESULTS: Two dogs had first intention healing in 15 days, whereas 1 dog developed necrosis of 10% of the flap, and this area healed by second intention. CONCLUSION: In male dogs, the scrotal skin can be used as a pedicle flap for reconstructive surgery of wounds in the perineum and the proximomedial and caudal aspect of the thigh. CLINICAL RELEVANCE: The perineal region remains a surgical challenge because of the lack of the available skin for reconstruction of surgical wounds. The scrotal skin should be considered for use as a transposition flap to cover skin defects in this region.     

A Comparison of the Cutaneous Trunci Myocutaneous Flap and Latissimus Dorsi Myocutaneous Flap in the Dog

Latissimus dorsi and cutaneous trunci myocutaneous flaps of equal dimension and location were randomly elevated on opposite sides of the thorax in 10 dogs (group 1) and resutured to their respective bed. The procedure was repeated in four additional dogs (group 2); however, the short perforating branches of the thoracodorsal artery and vein were divided at the base of each cutaneous trunci myocutaneous flap, whereas the cutaneous pedicle and underlying cutaneous trunci muscle were divided in the latissimus dorsi myocutaneous flaps to determine subsequent skin survivability and the major source of circulation of each myocutaneous flap. There was little difference in the percentage of skin survival between the latissimus dorsi and cutaneous trunci myocutaneous flaps in group 1 dogs. Circulation to the "skin island" of group 2 latissimus dorsi myocutaneous flaps originated from intramuscular anastomotic connections between the major branch of the thoracodorsal artery entering the latissimus dorsi muscle and the proximal lateral intercostal arteries perforating the muscle. Ligation of the short perforating branches of the thoracodorsal artery resulted in partial skin necrosis in all group 2 cutaneous trunci myocutaneous flaps. Results from this study indicate that it is unnecessary to elevate the latissimus dorsi muscle for major skin flap elevation and survival. The thicker latissimus dorsi myocutaneous flap is more difficult to develop surgically and appears to have no clinical major advantage over the more mobile cutaneous trunci myocutaneous flap or the adjacent thoracodorsal axial pattern flap for closure of large skin defects within the radius of flap rotation.     

Assessment of a caudal external thoracic artery axial pattern flap for treatment of sternal cutaneous wounds in birds

OBJECTIVE: To assess the use of a caudal external thoracic artery axial pattern flap to treat sternal cutaneous wounds in birds. ANIMALS: 16 adult Japanese quail. PROCEDURE: A cutaneous defect in the region of the mid-sternum was surgically created in all quail. In 6 quail (group I), an axial pattern flap was created from the skin of the lateral aspect of the thorax and advanced over the sternal defect. In 8 quail (group II), a flap was similarly created and advanced but the flap vasculature was ligated. All quail were euthanatized at 14 days after surgery and had necropsies performed. Sections of the flap and the surrounding tissue were examined histologically to assess flap viability. RESULTS: All axial pattern flaps in group-I quail had 100% survival. In group II, mean percentage area of flap survival was 62.5%; mean area of necrosis and dermal fibrosis of flaps were significantly greater than that detected in group I. In flaps of group-II quail, neovascularization in the deep dermis and profound necrosis of the vascular plexus in the superficial dermis were observed. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that the caudal external thoracic artery axial pattern flap could be used successfully in the treatment of surgically created sternal cutaneous defects in quail with no signs of tissue necrosis or adverse effects overall. Use of this technique to treat self-mutilation syndromes or application after surgical debulking of tumors or other masses might be beneficial in many avian species.     

Bilateral skin fold rotation-advancement flaps for the closure of large lumbosacral wounds in three dogs

Three dogs were presented for the management of disease processes resulting in large skin defects over the dorsal lumbosacral region. One had severe dog bite wounds, one had a large burn sustained from a heating pad and one had a large myxosarcoma in the region. In each case, the extent and location of the resulting skin defect were assessed as factors likely to prevent reconstruction using simple tension-relieving techniques alone or in combination with established reconstructive techniques, such as axial pattern flaps or skin stretching devices. Bilateral skin fold rotation-advancement flaps (SFRAFs) based on the flank folds were mobilised dorsally and allowed complete wound closure in two dogs and subtotal closure in the other dog. All wounds healed without major complications and an acceptable cosmetic outcome was achieved in each case. Minor flap debridement was required in two dogs. The use of bilateral SFRAFs is a useful technique alone or in combination with other reconstructive techniques for the closure of large dorsal lumbosacral skin defects when existing techniques are not sufficient. Small flank folds, such as those of obese dogs, may yield unexpectedly large SFRAFs.     

Clinical evaluation of axial pattern skin flaps in dogs and cats: 19 cases (1981-1990).

Nineteen axial pattern skin flaps were used in 16 dogs and cats to provide skin for repair of extensive cutaneous defects. Retrospective evaluation of medical records was used to determine percentage flap survival, postoperative complications, and long-term outcome of axial pattern skin flaps. The most common indication for use of axial pattern flaps was to augment wound closure following tumor resection (n = 7). Other indications included trauma (n = 5), chronic nonhealing wounds (n = 4), urine-induced cellulitis (n = 1), idiopathic dermal necrosis (n = 1), and chronic lymphoplasmocytic dermatitis (n = 1). Mean flap survival (+/- SD) was 96% (+/- 8). Postoperative complications included wound drainage (n = 15), partial dehiscence of the sutured flap (n = 7), distal flap necrosis (n = 6), infection (n = 3), edema (n = 3), and seroma formation (n = 2). After a median follow-up time of 5 months, evaluation of animals indicated that surgery provided successful wound reconstruction with good cosmetic results. Reconstruction of large cutaneous defects is facilitated by axial pattern flap application regardless of cause of wound. Postoperative complications are common but amenable to standard wound management techniques such as drain placement and surgical debridement of devitalized distal flap skin.     

Axial Pattern Flap Based on the Genicular Branch of the Saphenous Artery in the Dog

Axial pattern flaps based upon the genicular branch of the saphenous artery and medial saphenous vein were developed in eight dogs. On one hind limb of each dog, the experimental flap was raised and immediately transferred to a cutaneous defect created over the lateral aspect of the lower limb distal to the stifle. A control flap was elevated and transferred on the opposite hind limb with the genicular branches of the saphenous artery and vein ligated and divided at the base of the flap. Eighty-nine per cent of the length of the flap survived in those flaps in which the genicular vessels were left intact, whereas only 54% of the flap's length survived in the control flaps. Postoperatively, all dogs were bearing weight on the limbs normally. The genicular axial pattern flap may have special clinical application in cases of cutaneous defects involving the lateral aspect of the tibia.     

Angularis oris axial pattern buccal flap for reconstruction of recurrent fistulae of the palate

OBJECTIVE: To describe the use of an axial pattern flap based on the angularis oris artery and vein for reconstruction of palate defects. STUDY DESIGN: Clinical case report ANIMALS: Two dogs with recurrent oronasal fistulae. METHODS: Oronasal fistulae previously treated by buccal mucosal random pattern flaps that subsequently dehisced were repaired using an angularis oris-based buccal tissue axial pattern flap. This flap was developed by full thickness incision of the cheek tissue, excluding the skin, about the angularis oris vascular pedicle resulting in a vascularized flap covered by oral mucosa on one side. RESULTS: In one dog, the repair was intact and healed 6 months after surgery. In the second dog with a fistula that resulted because of radiation necrosis, approximately 95% of the defect healed with a small (<1.0 cm(2)) area of dehiscence. Repair of this persistent fistula with a random pattern buccal flap failed and this small fistula remained with minimal clinical signs. CONCLUSION: An axial pattern flap based on the angularis oris artery and vein can be used to repair difficult or recurrent palate defects. CLINICAL RELEVANCE: Angularis oris axial pattern flaps provide an additional effective option for repair of defects in the hard and soft palate to the distal gingival margin of the canine tooth or beyond, depending on skull conformation. Advantages of this flap include its highly vascular and robust character, high degree of mobility and a surface of tough buccal mucosa.     

Axial Pattern Flap Based on the Cutaneous Branch of the Superficial Temporal Artery in Dogs: An Experimental Study and Case Report

OBJECTIVE: To determine the anatomic guidelines and viability of an axial pattern flap based on the cutaneous branch of the superficial temporal artery (STA) in dogs. Application of the flap in a clinical patient is reported. STUDY DESIGN: Flap viability in control and experimental groups was determined 7 days postoperatively. ANIMALS: A total of 14 mature, mesaticephalic dogs; 1 clinical patient. METHODS: The cutaneous branch of the STA and vein were incorporated in the flaps of the experimental groups (group A, n = 5; group B, n = 4) and were ligated in the control group (n = 5). Flap length was extended in experimental group B. Seven days postoperatively, the length and area of tissue that remained viable in each flap was determined and compared with similar measurements performed intraoperatively. Cutaneous fluorescence was also used postoperatively to assess flap perfusion. The flap used in the clinical patient had the same dimensions as flaps developed in group A. RESULTS: Mean survival length (+/- SD) of STA flaps [group A, 9.1 (0.8) cm], was significantly increased (P < .05) compared with control flaps [7.0 (0.6) cm]. Percentage flap length survival (+/- SD) of STA flaps [group A, 91.8 (8.9)%], was significantly increased (P < .05) compared with control flaps [71.6 (7.0)%]. Mean percentage area of survival (+/- SD) of STA flaps [group A, 93.1 (7.5)%], was significantly increased (P < .05) compared with control flaps [73.5 (7.4)%]. Group B flaps had a mean survival length of 10.4 (1.1) cm, percentage flap length survival of 69.5 (4.8)%, and mean percentage area of survival of 69.1 (6.5)%. There was no positive correlation between the area of flap fluorescence at days 0, 1, and 3, and the area of flap survival. Application of the flap in a clinical patient allowed primary wound reconstruction with 100% survival. CONCLUSION: A flap based on the cutaneous branch of the STA may be a source of skin for reconstructive procedures of the maxillofacial region in dogs. CLINICAL RELEVANCE: Knowledge of the anatomic landmarks and expected viability of a STA axial pattern flap is essential before consideration of its use as a reconstructive surgical technique.     

Evaluation of surgical margins required for complete excision of cutaneous mast cell tumors in dogs

OBJECTIVE: To determine whether neoplastic mast cells extended into tissue 1, 2, or 3 cm laterally or deeper than 1 fascial plane from the visible edge of cutaneous mast cell tumors (MCTs) in dogs. DESIGN: Prospective study. ANIMALS: 21 client-owned dogs with > or = 1 cutaneous MCT PROCEDURES: After preparation for surgery, each dog's skin was marked 1, 2, and 3 cm from the tumor edge at 0 degrees, 90 degrees, 180 degrees, and 270 degrees. At each 3-cm mark, deep fascia was exposed and sutured to the skin; the tumor was excised in routine fashion and fixed in formalin. Tumors were graded; margins were examined histologically for neoplastic mast cells. RESULTS: 23 cutaneous MCTs in 21 dogs were included in this study. Fifteen (65%) tumors were located on the trunk, 5 (22%) on the hind limbs, and 3 (13%) on the head and neck. There were 3 (13%) grade-I and 20 (87%) grade-II tumors. All grade-I tumors were completely excised at all margins. Seventy-five percent of the grade-II tumors were completely excised at the 1-cm margin, and 100% were completely excised at the 2-cm margin. Two grade-II MCTs located on the hind limbs of dogs were excised with a complete but close (within 1 mm) deep margin. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that a 2-cm lateral margin and a deep margin of 1 fascial plane appear to be adequate for complete excision of grade-I and -II MCTs in dogs.     

Complications and outcome after thoracodorsal axial pattern flap reconstruction of forelimb skin defects in 10 dogs, 1989-2001

OBJECTIVE: To determine (1) the frequency and extent of complications associated with thoracodorsal axial pattern flap reconstruction of forelimb skin defects in dogs and (2) outcome after treatment of such complications. STUDY DESIGN: Retrospective clinical study. SAMPLE POPULATION: Ten dogs. METHODS: Medical records for 10 dogs that had a thoracodorsal axial pattern skin flap reconstruction of a forelimb skin defect were reviewed. RESULTS: Three dogs had complete flap survival. Partial necrosis of the distal flap, ranging from an estimated 2% to 53% (mean, 21%) of the flap surface area, occurred in 7 dogs. Six dogs required surgical management of the skin necrosis, resulting in successful resolution in 5 dogs, whereas, in 2 dogs, the wound healed by second intention. Positive bacterial cultures were obtained from 3 dogs with distal flap necrosis. Seroma formation was noted in 2 dogs; the entire flap survived in 1 dog, whereas the second dog developed distal flap necrosis. Edema and bruising of the distal portion of the flap were noted in 8 dogs; distal flap necrosis subsequently developed in 7 dogs. Partial incisional dehiscence, which healed by second intention, occurred in 2 dogs. Of 6 owners available for follow-up, all were satisfied with the functional outcome, but 1 owner was not satisfied with the cosmetic appearance. CONCLUSIONS: Partial flap necrosis was a frequent complication of thoracodorsal axial pattern flap reconstruction of forelimb skin defects and required additional wound care or surgical intervention to achieve healing. CLINICAL RELEVANCE: Thoracodorsal axial pattern flaps can provide full-thickness skin coverage of extensive skin defects of the forelimb, but owners should be aware of the likelihood of local wound complications.     

Use of a latissimus dorsi myocutaneous flap for one-stage reconstruction of the thoracic wall after en bloc resection of primary rib chondrosarcoma in five dogs

Objective— To describe a thoracic wall reconstructive technique using a latissimus dorsi myocutaneous flap after en bloc resection of primary rib chondrosarcoma and report outcome in 5 dogs.
Study Design— Retrospective study.
Animals— Dogs (n=5) with primary rib chondrosarcoma.
Methods— Medical records (2003–2005) were reviewed for signalment, staging investigations, surgical findings, complications, and outcomes. Owners and veterinary surgeons were contacted for outcome information.
Results— A latissimus dorsi myocutaneous flap provided an air-tight thoracic wall closure after chondrosarcoma resection. Paradoxical respiratory movement of the flap occurred; however, from physical examination and blood gas analysis (2 dogs), ventilation was adequate. All flaps survived, 1 had superficial skin necrosis distally and 2 had minor wound dehiscence. One dog without tumor-free margins died of tumor-related disease 56 days after surgery. Tumor recurrence did not occur in 4 dogs with tumor-free margins. One dog was euthanatized 10 months after surgery for unrelated disease; 3 dogs were alive at writing (median follow-up: 20 months; range, 18–27 months) and all had a satisfactory functional and cosmetic outcome.
Conclusions— Reconstruction of ventral thoracic wall defects using a latissimus dorsi myocutaneous flap yields a functional, cosmetic outcome.
Clinical Relevance— A latissimus dorsi myocutaneous flap can be used as a successful 1-stage reconstructive technique for ventral thoracic wall defects.     

Misapplication of Subcutaneous Pedicle Flaps in the Dog

Subcutaneous pedicle flaps were created in 21 dogs, 1) with an intact underlying panniculus muscle, 2) with a severed panniculus muscle, and 3) devoid of an underlying panniculus muscle. The survival rates of the resultant grafts were evaluated over a minimum of ten days. All 19 subcutaneous pedicle flaps survived when the underlying panniculus muscle was intact. Nineteen of 23 flaps with a severed panniculus muscle, however, developed necrosis. The survival rates between these two groups were significantly different (p < 0.01). Eight of 14 flaps developed without an underlying panniculus muscle underwent necrosis. Their survival rate was significantly different from flaps with an intact panniculus muscle (p < 0.01) but not significantly different from flaps without an intact panniculus muscle (p < 0.1). Four of 23 subcutaneous pedicle flaps with severed panniculus muscles and six of 14 flaps without an underlying panniculus muscle survived, despite apparent vascular compromise. Six of these grafts survived by accidental incorporation of a direct cutaneous artery and vein beneath the graft. Results from this experiment indicate that subcutaneous pedicle flap development in the dog has a high incidence of necrosis unless a panniculus pedicle to the overlying skin is preserved. As such, they have no advantage in the dog over safer and simpler closure techniques, which preserve the cutaneous circulation.     

Transfer of Free Vascular Cutaneous Flaps by Microvascular Anastomosis Results in Six Dogs

Skin defects on the distal extremities of six dogs were reconstructed with free vascular cutaneous transfers by microvascular anastomosis. The donor flaps were based on the superficial cervical artery and vein. In five of the dogs, bone was exposed and skin was lost from half of the circumference of the limb. Two had infected fractures with sequestra and three had acute shearing injuries. The sixth dog had sensory denervation of the left antebrachium and a carpal acral lick granuloma. Before surgery, the patency of potential recipient vessels was confirmed with arteriography in five dogs and an ultrasonic doppler in one dog. Microvascular technique was used to reestablish circulation to the flaps after they were transferred to the recipient site. Total ischemic time of the flaps averaged 100 minutes. All flaps survived. Successful reconstruction of the cutaneous defects was achieved in these six cases.     

Standard and modified glabellar flap for medial canthus reconstruction following mass removal in three dogs and two cats

Purpose

To describe the surgical technique and clinical outcomes of the glabellar flap and its modification for the reconstruction of the medial canthus following resection of tumors in three dogs and two cats.

Methods

Three dogs (7-, 7-, and 12.5-year-old mixed breeds) and two cats (10- and 14-year-old Domestic shorthair) presented with a 7–13 mm tumor affecting the eyelid and/or conjunctiva in the medial canthal region. Following en bloc mass excision, an inverted V-shaped skin incision was made in the glabellar region (i.e., the area between the eyebrows in humans). The apex of the inverted V-shaped flap was rotated in three cases, whereas a horizontal sliding movement was performed in the other two cases to better cover the surgical wound. The surgical flap was then trimmed to fit the surgical wound and sutured in place in two layers (subcutaneous and cutaneous).

Results

Tumors were diagnosed as mast cell tumors (n = 3), amelanotic conjunctival melanoma (n = 1), and apocrine ductal adenoma (n = 1). No recurrence was noted in a follow-up time of 146 ± 84 days. Satisfactory cosmetic outcome with normal eyelids closure was achieved in all cases. Mild trichiasis was present in all patients and mild epiphora was noted in 2/5 patients, but there were no associated clinical signs such as discomfort or keratitis.

Conclusions

The glabellar flap was easy to perform and provided a good outcome in terms of cosmetic, eyelid function, and corneal health. Postoperative complications from trichiasis appear to be minimized by the presence of the third eyelid in this region.     

Evaluation of primary critical ischemia time for the deep circumflex iliac cutaneous flap in cats

OBJECTIVE: To evaluate the primary critical ischemia time for the deep circumflex iliac (DCI) cutaneous flap in cats. STUDY DESIGN: In vivo model. ANIMALS: Thirteen young adult female cats. METHODS: An island skin flap was created on the right side of each cat based on the angiosome of the ventral branches of the DCI vessels. The cats were randomly assigned to a flap ischemia time ranging from 1 to 3 hours in 10-minute intervals. Microvascular clamps were used to occlude the artery and vein for the designated time. Flaps were sutured into position after the ischemic period. On day 3, fluorescein dye was administered and the flaps were evaluated under ultraviolet light to assess percent area of perfusion. On days 7 and 14, the percent area of survival was determined for each flap based on cutaneous morphometry. RESULTS: All flaps had 100 percent area of survival throughout the study. On day 3, all flaps fluoresced uniformly compared with the surrounding skin. On days 7 and 14, all flaps were uniformly viable as confirmed by skin color, consistency, bleeding, and hair re-growth. CONCLUSION: The DCI cutaneous flap in cats can withstand up to 3 hours of ischemia with predictable survival. CLINICAL RELEVANCE: In a clinical setting, high success rates can be expected with microvascular transfer of the DCI cutaneous flap in cats when the ischemia time is <3 hours and precise surgical technique is used.     

Deep circumflex iliac cutaneous free flap in cats

OBJECTIVE: To develop and assess the survival of a microvascular cutaneous free flap based on the ventral branch of the deep circumflex iliac (DCI) artery and vein in cats. STUDY DESIGN: Experimental study. ANIMALS: Phase 1: 6 feline cadavers; Phase 2: 2 adult cats; Phase 3: 10 adult cats. METHODS: Phase 1: Selective angiographic study of the deep circumflex iliac artery was completed in 6 feline cadavers. After injection of the DCI artery with barium, high-detail radiographs were made of skin flaps harvested from the lateral flank and thigh region. The extent of the cutaneous angiosome was mapped with regard to the underlying anatomical landmarks. Phase 2: An island flap based on anatomic boundaries of the DCI angiosome derived from phase 1 of the study was elevated in 2 cats. Flaps were observed for 3 weeks for survival. Phase 3: Free skin flaps based on the DCI vessels were harvested in 10 cats and transferred to the dorsal interscapular region. Flaps were evaluated for 2 weeks for survival. Tissue samples were collected for histopathology, and angiograms of the flaps were completed. RESULTS: Phase 1: Angiograms revealed a large primary cutaneous angiosome of the DCI artery located over the lateral femoral region, which extended from the iliac crest to the level of the patella. Phase 2: All island flaps survived for 3 weeks. Phase 3: Six free flaps survived for 2 weeks, and 4 flaps failed completely. Failure of 1 flap occurred because of avulsion of the venous and arterial anastomosis postoperatively. Another cat had intraoperative hemorrhage, which resulted in anemia and hypovolemia and likely caused the flap to fail. The other 2 flaps that failed had poor perfusion intraoperatively and had the longest ischemia times. CONCLUSIONS: The cutaneous DCI free flap in cats may be clinically useful in reconstruction of large cutaneous wounds. The length of ischemia time for successful cutaneous free flap transfer in the cat may be shorter than in other species. CLINICAL RELEVANCE: Large wounds created by trauma or oncologic ablative surgery in cats could be reconstructed with cutaneous microvascular free flap. Additional studies assessing the critical ischemia time of cutaneous flaps in cats and evaluating the use of this flap clinically are needed.     

Direct cutaneous arterial supply to the tail in dogs.

Cutaneous arterial blood supply to the tail was evaluated in 12 dogs. Subtraction radiography of internal iliac artery and distal aorta angiography in 3 of these dogs was used to determine arterial blood supply to the tail from the median sacral and lateral caudal arteries. Dissection of the tail in 8 canine cadavers revealed bilateral subcutaneous location of lateral caudal arteries following tail amputation. An axial pattern flap based on the lateral caudal arteries contributed to the reconstruction of a large caudodorsal cutaneous defect in a dog. An axial pattern flap based on the lateral caudal arteries following tail amputation may be indicated to aid reconstruction of large caudodorsal cutaneous defects of the trunk in dogs.