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Biomedical subjects

Abdullah Keçik

Publications and source records attributed to Abdullah Keçik.

13 recordsLinked to original sources
PubMed2006

Neuromuscular and neuromusculocutaneous flaps in the rat.

Since the introduction of flaps based on the vascular structures of the cutaneous nerves, these have gained increasing popularity in reconstructive surgery. The purpose of this study is to describe a new concept in which the flap is supplied solely by the intrinsic vasculature of a motor nerve. A total of 94 Wistar rats weighing 200-250 g were used in this experiment, which was divided into three sections. In section I, the neural anatomy of the posterior thigh region was investigated. In section II, the flap study using experimental and control groups, was performed. In the experimental group neuromuscular and neuromusculocutaneous flaps were created. The biceps femoris muscle was harvested based solely on its motor nerve as a neuromuscular flap, and together with its overlying skin it was similarly raised as a neuromusculocutaneous flap. In the control group, conventional muscle and musculocutaneous flaps were harvested based on the caudal femoral-popliteal artery vascular axis, and a graft subgroup was created ligating both the constant vascular structure and the motor nerve. In section III, with the intention of augmenting the survival areas of neuromuscular and neuroumusculocutaneous flaps, a surgical delay procedure was applied. On postoperative day 7, the viability of all flaps was evaluated using direct observation, microangiography, and tetrazolium blue stain techniques. The results of the anatomic studies demonstrated a consistent motor nerve arising from the sciatic nerve to the biceps femoris muscle with evident perineural vasculature. Average muscle viability levels of neuromuscular, neuromusculocutaneous, delayed neuromuscular, delayed neuromusculocutaneous, conventional muscle and musculocutaneous flaps were 20.6 +/-7.58, 22.4 +/- 4.21, 86.4 +/- 6.14, 85 +/- 4.21, 89.6 +/- 4.48, and 88.0 +/- 5.51%, respectively. Survival levels of the skin paddles of the neuromusculocutaneous, delayed neuromusculocutaneous, and conventional musculocutaneous flaps were calculated as 13 +/- 17.51, 67 +/- 30.29, and 97+/-4.21%, respectively. In the graft subgroup the viability of muscle and skin paddle was almost nil. In conclusion, our new flap model in a favored laboratory animal is of benefit to researchers in providing a means for future various types of investigations into this new concept. The technique might be considered in further experimental research studies and appropriate clinical situations.

Animals↗
PubMed2004

A new epineural nerve repair technique with external metallic circle.

BACKGROUND: Despite the existence of various nerve coaptation techniques, functional results of nerve repair are still inadequate. Potential benefits of developing modified coaptation techniques cannot be disregarded. METHODS: The authors report a new coaptation technique in which the epineural sutures were performed with an external metallic circle to increase the coaptation surface. The sciatic nerves of 30 male Wistar albino rats were used in the study. RESULTS: The mean Sciatic Function Index values in external metallic circle repair (n:11) and conventional epineural repair (n:10) groups were -42.35 +/- 22.95 and -69.34 +/- 17.96, respectively (p = 0.020). Electrophysiological studies revealed that the duration of compound muscle action potentials (CMAP) was (p = 0,012) shorter in conventional nerve repair group than it was in external metallic nerve repair. When external metallic circle repair and conventional epineural repair groups were examined for distal nerve segments, there were significant findings for the diameter of axons (p = 0.005), diameter of nerves (p = 0.000), and for G ratios (p = 0.000). The mean intraepineural cross sectional areas of external metallic circle repair and conventional epineural repair groups were 3.57 +/- 0.21 and 2.92 +/- 0.23 mm(2), respectively (p = 0.000). CONCLUSION: The external metallic circle repair technique enhances nerve regeneration by enabling a larger sprouting and contact area for nerve fibers.

Animals↗
PubMed2004

A new flap design: neural-island flap.

This report introduces the "neural-island flap" concept, which represents a consistent and reliable skin flap design supplied only by the intrinsic vasculature of a cutaneous nerve. In this study, the lateral femoral cutaneous nerve was selected as the pedicle of the neural-island flap, and a standard skin flap, which is the territory of the accompanying vessels (i.e., iliac branches of the iliolumbar artery and vein), was elevated on the lower dorsal region of the rats. In a total of 92 Wistar rats, three experiments were performed. In part I (n = 24), the vascular anatomy of the lateral femoral cutaneous nerve was established by the methods of dissection, microangiography, nerve mapping, perfusion with colored latex and India ink, and histologic analysis. In part II (n = 46), the role of the cutaneous nerve in supporting an acutely elevated skin flap was explored by creating five flap groups as follows: group 1, conventional flap (artery, vein, and nerve intact); group 2, neural island flap (only the nerve intact); group 3, neurocutaneous flap (vein and nerve intact); group 4, denervated flap (artery and vein intact); and group 5, skin graft. In part III (n = 22), the role of a preliminary surgical delay procedure to augment the survival of the neural island flap was investigated. Results of the anatomic studies indicated a consistent perineural vasculature by the accompanying iliolumbar artery. Skin flaps survived totally in groups where the artery and vein were intact, whereas mean survival rates for the neural island flap and the neurocutaneous flap were 38.2 +/- 3.1 percent and 44.5 +/- 3.8 percent, respectively (p > 0.05). Results of part III of the experiment demonstrated a significantly higher survival for the delayed neural island flap (94.5 +/- 5.5 percent) compared with the acutely elevated neural island flap (p < 0.05). The perineural and intraneural vessels were found to be greatly dilated after a delay procedure, demonstrated by direct observation, microangiography, histologic analysis, dye injection study, and scanning electron microscopy. On the basis of this promising series of experiments, a clinical technique was developed using the sural neural-island flap. The flap was used to reconstruct lower extremity defects in four cases. A delay procedure was accomplished in the first stage by elevating a fasciocutaneous flap from the midcalf region based on a posterior skin bridge and the sural nerve. After a 2-week delay period, a sural neural-island flap was created based on the nerve and transposed to the defect. Flap survival was complete in all cases, with a satisfactory result. The authors conclude that this report proves for the first time that a robust and reliable skin flap can be created pedicled only by the intrinsic vasculature of a cutaneous nerve, after a proper surgical delay. The so-created neural-island flap design offers two novel advantages: (1) a very narrow pedicle and (2) a pedicle without any restriction to a specific pivot point, in addition to the previously described unique advantages of preservation of a major artery and avoidance of microvascular anastomoses.

Adult↗
PubMed2004

Microsurgical revascularization of almost totally amputated alar wing of the nose.

A case of nearly complete amputation of the alar wing is presented whereby a successful arterial revascularization was accomplished using an arterial rerouting technique. Venous stasis was overcome by means of stab-wound wiping. An excellent result was obtained following complete survival of the revascularized segment. The authors conclude that microvascular revascularization should always be attempted whenever possible, even if a skin bridge is preserved in nearly complete amputations of the nose.

Adult↗
PubMed2003

Oblique radial forearm reverse-flow flap.

A modifed design for the distally-based radial forearm flap is presented, in an oblique direction rather than longitudinally, based on the existence of skin laxity in the proximal forearm region. The skin paddle of the flap is designed in an oblique fashion pedicled on one of the proximal-row septocutaneous perforators, and elevated in the usual manner supplied by the distal radial artery. The oblique radial forearm flap thus created was successfully utilized for reconstruction of seven dorsal hand defects. Results showed that all the flaps could easily be transposed to the defect through a wide arc of rotation and all survived totally, with direct closure of the donor site in five cases, and significant reduction in size in the remaining two cases. It was concluded that the oblique design for the skin island of the reverse radial forearm flap could allow creation of a flap that has a smaller donor defect and yet presents a longer pedicle length, with a wider arc of rotation and better adaptation to a dorsal hand defect, than a conventional longitudinal-design radial forearm flap.

Adult↗
PubMed2003

Easy method of capturing microscopical images by using a consumer-type digital camera.

Taking pictures of microstructures is difficult, requiring sophisticated cameras coupled by the microscopes. Furthermore, it may not be feasible to find an operating microscope paired with a camera, especially in laboratory conditions. Considering the difficulty of obtaining microscopic photographs in clinical and laboratory settings, this report describes a practical method of digital photography of microstructures using a consumer-type digital camera. The technique can be summarized simply as placing the lens of a consumer-type digital camera over the eyepieces of a surgical microscope, whereby the anatomic structure of interest is focused. The image thus obtained is transferred to the computer, using easily available software programs. The authors conclude that this method is an inexpensive and practical way of capturing photographs of microstructures, obviating the need for using microscopes coupled by the cameras.

Humans↗
PubMed2002

A simplified atraumatic technique for tunneling a nerve graft in a cross-face nerve-grafting procedure.

This report describes a simple and reliable method of tunneling a nerve graft in a cross-face nerve grafting procedure. In this technique, a subcutaneous tunnel is developed in two passes by means of a long hemostat that advances an 18F sterile tube from one side of the face to the other. The nerve graft is then attached to a heavy (1-0) polypropylene suture with a stitch that, by its inherent firmness, is easily threaded through the tube, dragging the nerve graft behind. Thus, the nerve graft can easily be delivered through the tube without any trauma. This technique has been used for seven patients without any complication. This is a simple and atraumatic technique for tunneling a nerve graft in a cross-face nerve grafting procedure.

Esthetics↗
PubMed2002

Ring avulsion replantation by extended debridement of the avulsed digital artery and interposition with long venous grafts.

Ring avulsion replantation is a technically challenging procedure with a very low success rate. Because the zone of arterial injury is more extensive than what it appears to be in such avulsion amputations, a technique was developed to debride the avulsed digital artery for a long distance, extending well into the digital pulp, thereby creating healthy arterial ends to be bridged by one or two segments of long venous grafts. Using this technical approach, 7 patients with complete amputations of ring avulsion injury (Urbaniak's class III) were operated. In all amputations the bone was disrupted at the distal interphalangeal level (except in 1 patient) and the soft tissues at the proximal phalanx level, with the proximal interphalangeal joint and the flexor digitorum superficialis tendons being intact. Results indicated that replantation was successful in all patients. However, 2 patients presented with unusually late arterial failure 28 and 30 days after surgery respectively. Although one of these cases was salvaged by reoperation, the other case (followed by conservative management) demonstrated partial distal necrosis. Therefore, the ultimate success rate in this series was 85% in the long term. At follow-up, sensibility was protective in all patients, with an average static two-point discrimination of 7.8 mm (range, 6-14 mm). The total active motion of the replanted digits was 194 deg on average (range, 155-205 deg) without loss of function of the proximal interphalangeal joint except in 2 patients who had late vascular problems. The authors conclude that microsurgical replantation of completely amputated ring avulsion injuries with an intact proximal interphalangeal joint and flexor digitorum superficialis tendon, is a worthwhile procedure that results in good functional and aesthetic results. Furthermore, using an aggressive approach for debridement of the avulsed digital artery, as described in this article, an experienced microsurgeon can replant successfully nearly all cases. However, one should be cautious in the follow-up of such patients, because late arterial failure may be encountered, as was observed in 2 patients in this series. The authors suggest immediate reoperation in such unusual circumstances.

Adult↗
PubMed2002

Free flap transfer to the dorsum of the rat: a new technique to avoid autocannibalization in free flap studies.

In this report the authors describe a new method that avoids autocannibalization by free transfer of a flap to the dorsum of the rat by means of a simple exposure technique. A total of 22 Wistar rats of both sexes (weight, 200-290 g) were used in this experiment. An anatomic study performed in 12 rats revealed that a wide exposure could be created in the axillary fossa by retracting the inferior tip of the scapular bone superiorly (after severing its attachments with the deep extrinsic back muscles), the latissimus dorsi muscle laterally, and the serratus anterior muscle medially. Furthermore, after obtaining vessel diameter measurements, it was ascertained that the subscapular and the lateral thoracic vessels could serve as the recipient vessels. Based on the anatomic study, a total of 10 conventional groin cutaneous flaps, measuring 2 x 3 cm in size, were harvested based on the femoral vessels and transferred to the dorsum of the same animal by the exposure method as just described, with microvascular anastomoses performed between the femoral vessels of the flap and either the subscapular artery and the lateral thoracic vein (N = 5) or the lateral thoracic artery and vein (N = 5). Results showed that 9 of the 10 transplanted flaps were totally viable on postoperative day 7, giving a success rate of 90%, with one failing flap belonging to the latter group. The authors conclude that by this simple method of recipient vessel exposure in the axillary fossa, free flap transfer to the dorsum of the rat is a simple and reproducible technique by microvascular anastomoses performed between the pedicle vessels of a flap and the subscapular artery and the lateral thoracic vein. This model offers the unique advantage of a dorsally located flap that is protected by autocannibalization. Moreover, daily observation and monitoring of the flap are easy and practical without the need to have the animal wear protective material such as vest.

Animals↗
PubMed2002

Dorsal penile vein as a new training model for microvenous anastomosis in rats.

The authors present a new model for microsurgical training of venous anastomosis-namely, the dorsal penile vein of the rat. In 12 male Wistar rats weighing 220 to 290 g, the anatomy of the dorsal penile vein was studied by dissection and histology. Anatomic dissection studies revealed that the dorsal penile vein has an average diameter of 1.4 mm (range, 1.2-1.6 mm) without tendency to collapse. The vein could be dissected for an average segment of 25 mm without any branches, allowing easy dissection and approximator clamp placement. Comparison of its cross-section with that of the femoral vein histologically by light microscopy and scanning electron microscopy revealed a larger diameter and much thicker vessel wall with a prominent tunica media and adventitia. Based on the findings of the anatomic study, the dorsal penile vein anastomotic model was created in the rat. In 20 animals, the vein was divided sharply in its midsection and was anastomosed end-to-end using standard microsurgical technique. Results indicated a 100% patency rate immediately after the anastomosis and a 90% patency rate (18 of 20) 1 week after the procedure. This model offers the advantages of easy dissection without ligation of any side branches and a thick vessel wall without a tendency to collapse. Moreover, a major limb vein is not sacrificed. It is concluded that this new model may better simulate the clinical procedure of microvenous anastomosis because it presents similarities to human veins.

Anastomosis, Surgical↗
PubMed2002

Technique to re-establish continuity of the recipient artery after end-to-end anastomoses in cross-leg free flap procedure.

In this report, a simple technique is described to restore the continuity of the recipient artery in cross-leg free flap procedure after end-to-end anastomoses. In the first stage, the latissimus dorsi flap was revascularized by end-to-end anastomosis between the posterior tibial artery of the noninjured leg and the thoracodorsal artery of the flap. After 4 weeks of neovascularization period, in the second stage when the pedicle was to be divided, the thoracodorsal artery was dissected until its bifurcation in the muscle, transected, and rerouted to the distal ligated end of the posterior tibial artery, accomplishing a simple end-to-end anastomosis between these two vessel ends. Thus, the continuity of the recipient artery was re-accomplished by replacing the normally discarded segment of the flap's arterial pedicle as an arterial graft, the patency of which was demonstrated clinically and by Doppler examination. The authors believe that this technique provides further benefit to the patient by accomplishing vascular flow through a major lower limb artery when the reconstructive pathway involves an end-to-end anastomosis in a cross-leg free flap procedure.

Anastomosis, Surgical↗