Kenan Atabay

Effect of Platelet-Rich Plasma on Peripheral Nerve Regeneration

Activated platelets release various growth factors, some of which are recognized to improve nerve regeneration. This study evaluated the effect of platelet-rich plasma (PRP) in end-to-end neurorrhaphy. A total of 45 Wistar rats were used, with the initial five used for PRP preparation. The right hind limbs were used as experimental, with the left as control. The animals were treated in five groups. Group A (n = 4): The right sciatic nerve was dissected only from the sciatic notch to the bifurcation. In all other groups, the nerve was sharply transected and repaired with: group B (n = 8): two sutures; group C (n = 8): six sutures; group D (n = 10): two sutures and PRP; and group E (n = 10): six sutures and PRP. Groups D and E were compared with groups B and C, respectively. Group E had a shorter latency time in electromyography ( P < 0.01) and a thicker myelin layer in the histological evaluation ( P < 0.003) in comparison with group C. These positive effects of PRP were not detected in the nerves were repaired with two sutures. In this animal model, the application of PRP to the repair site helped to improve remyelinization of the sciatic nerve in rats when the epineural repair was done with six sutures.

Reconstruction of Traumatic Orbital Floor Fractures With Resorbable Mesh Plate

Various materials such as autogenous bone, cartilage and alloplastic implants have been used to reconstruct orbital floor fractures. A new material is needed because of disadvantages of nonresorbable alloplastic materials and difficulties in harvesting autogenous tissues. In this study safety and value of the use of resorbable mesh plate in the treatment of orbital floor fractures are discussed. Between 2002 and 2004 a total of 17 maxillofacial trauma patients complicated with orbital floor fractures were treated with resorbable mesh plate through subciliary or transconjunctival incisions. Pure blow-out fractures were determined in 6 patients and 11 patients had accompanying maxillofacial fractures. Resorbable plate was easily shaped to fit to the orbital floor by cutting with scissors. Patients were evaluated clinically and with computed tomography scans preoperatively and at 3-, 6- and 12-month intervals postoperatively. Twelve patients had preoperative enophthalmos. Two patients had diplopia that was corrected postoperatively. In all 17 cases there was no evidence of infection, diplopia and gaze restriction postoperatively. Scleral show appeared in three patients by the second postoperative week but resolved totally within 3 to 6 weeks except one patient. In this patient anterior displacement of mesh was evident which caused ectropion and enophthalmos and required re-operation. No any other mesh related problems were seen at 15 months mean follow-up time. The advantage of the resorbable mesh system in orbital floor fracture is the maintenance of orbital contents against herniation forces during the initial phase of healing and then complete resorption through natural processes after its support is no longer needed. Our experience represents that resorbable mesh is a safe and effective material for reconstruction of the selected, non-extensive orbital floor fractures.

Surgical treatment of urethral fistulas following hypospadias repair.

&NA; Development of urethral fistulas is one of the most common late complications of hypospadias surgery. A total of 161 male patients who had 186 urethrocutaneous fistulas were first classified according to the fistula classification of Horton and colleagues and then treated with three types of procedures: simple closure, local rotation flaps, or tube graft reconstruction. With initial surgical intervention, 156 of 186 fistulas were treated successfully. The remaining 30 fistulas (16.1%) recurred during the follow‐up period. In the recurrent cases, immediate closure was not preferred, and an average of 6 months was waited before considering any additional surgical attempt. Distal cases had a higher failure rate, and the simple closure technique failed to show a success rate as high as local flap or tube graft repair. The high recurrence of distal cases was attributed mainly to the lack of adequate soft tissue adjacent to the fistula, which is vital for safe closure. In addition, the traction effect of erection on the skin and urethra, which is more prominent distally than proximally, is also believed to play an additive role. To increase success, the selection of appropriate treatment modality and customization of techniques for each patient cannot be overemphasized. However, the authors conclude that careful presurgical assessment of the patient, a 6‐month delay before any secondary surgical attempt, inversion of the urethral mucosa, avoidance of any overlapping suture lines, urinary diversion proximal to the repair site for 5 to 11 days, and usage of thin, absorbable suture materials are the main criteria that should be met for a satisfactory hypospadias fistula repair. Latifoğlu O, Yavuzer R, Ünal Ŝ, Çavuşoğlu T, Atabay K. Surgical treatment of urethral fistulas following hypospadias repair. Ann Plast Surg 2000;44: 381‐386

Delayed effect of denervation on wound contraction in rat skin.

&NA; Neuronal supply in soft tissues may be an important part of cutaneous wound healing. In order to observe the effect of denervation on wound contraction, rectangular full‐thickness skin defects were created on the dorsum of two groups of Wistar rats. In the experimental group (n = 20), spinal nerves corresponding to the area of the open wound (T11 to L2) were isolated and divided bilaterally. In the control group (n = 20), the same pairs of spinal nerves were dissected but left intact. Limits of denervation were verified by the pinprick test. Wound healing, which is primarily in the form of wound contraction in this model, was evaluated by tracing wound margins onto millimetric paper weekly. Wound contraction was delayed significantly in the experimental group (p < 0.05) at all follow‐up periods when compared with the controls. Loss of neuropeptide secretion from the nerve endings in denervated tissues may be responsible for the retarded wound contraction, since neuropeptides are thought to exert trophic effects on skin wound healing.

The treatment of burn scar hypopigmentation and surface irregularity by dermabrasion and thin skin grafting.

Scar tissue and leukoderma-type discoloration of the skin due to deep burns are treated by dermabrasion and thin split-thickness skin-graft application. This method was applied to 18 patients on whom the treated lesion sites were located as follows: 8 in the facial area, 9 on the extremities, and 1 on the neck. Adequate repigmentation and flat surfaces were obtained in all patients at the end of 6 months, and results persist at the end of a considerable follow-up period (1 to 4 years). The technique, advantages, disadvantages, and results are discussed.

The effect of gradually increased blood flow on ischemia-reperfusion injury.

Even with excellent operative techniques, prolonged ischemic periods may cause unwanted results because of a complex mechanism called reperfusion injury. Various pharmacological and immunological agents have been used to prevent this type of injury. Another known way to diminish reperfusion injury is the gradual reperfusion of the ischemic tissues. In this study, the effect of a gradual increase in blood flow on ischemia-reperfusion injury of the skeletal muscle was investigated. The right hind limbs of 15 rats were partially amputated, leaving the femoral vessels intact. Preischemic femoral arterial blood flow was measured by using a transonic small-animal blood flowmeter (T106) in all animals. The rats were divided into three groups: Group I consisted of control rats; no ischemia was induced. Group II was the conventional clamp release group. Clamps were applied to the femoral vessels to induce 150 minutes of ischemia. The clamps were then released immediately and postischemic blood flow was measured. Group III was the gradual clamp release group. After 150 minutes of ischemia, clamps were released gradually at a rate so that the blood flow velocity would reach one fourth the mean preischemic value at 30 seconds, one half at 60 seconds, three fourths at 90 seconds, and would reach its preischemic value at 120 seconds. Total clamp release was allowed when blood flow was less than 1.5 fold of the preischemic values. Postoperatively the soleus muscles were evaluated histopathologically, and malonyldialdehyde and myeloperoxidase levels were measured. The mean preischemic blood flow was 13.6 ± 2.24 ml per kilogram per minute in all groups. In the conventional release group, postischemic flow reached four to five fold its preischemic values (61.06 ml per kilogram per minute). Histopathology revealed more tissue damage in the conventional release group. Malondialdehyde and myeloperoxidase levels were also significantly lower in the gradual release group. Depending on histological and biochemical findings, a gradual increase in blood flow was demonstrated to reduce the intensity of ischemia-reperfusion injury in the soleus muscle of this animal model.Ünal Ş, Özmen S, Demİr Y, et al. The effect of gradually increased blood flow on ischemia-reperfusion injury. Ann Plast Surg 2001;47:412–416

Sociological aspects of rhinoplasty.

Although the psychological aspect of the rhinoplasty operation has been a subject of interest for a long time, with the exception of a few studies, sociological factors have been almost totally ignored. In this prospective study the personality characteristics and socioeconomic backgrounds of 216 rhinoplasty patients were evaluated. Between 1994 and 2000, a questionnaire and the Minnesota Multiphasic Personality Inventory (MMPI) were given preoperatively to 157 females and 59 males. The MMPI was also given to age-matched people as a control. Six months after surgery, patients were called on the telephone and asked to rate their satisfaction. According to questionnaire, a great majority of the rhinoplasty patients were young, unmarried women with high education levels. In the rhinoplasty group, one or more scales of the inventory were not in the normal ranges in 45% of the patients, whereas this proportion in the control group was 28% (p < 0.01). When MMPI results are considered, female patients of this study could be described as egocentric, childish, highly active, impulsive, competitive, reactive, perfectionistic about themselves, talkative, and emotionally superficial. Male patients could be described as rigid, stubborn, over-sensitive, suspicious, perfectionistic, pessimistic, over-reactive, and having somatizations. Tension and anxiety with feelings of inferiority were found to be characteristics of the male patients. The satisfaction rate after six months was reported as 72%. There was no significant correlation between MMPI results and demographic variables, nor satisfaction rate. In conclusion, the rhinoplasty patients in our study are young people at the very beginning of their careers. It could be that their personalities and socioeconomic backgrounds combine to make aesthetic surgery rewarding enough, both socially and personally, to encourage them to follow through.

Effect of platelet-rich plasma and fibrin glue on healing of critical-size calvarial bone defects.

Despite the insufficient number of experimental studies, platelet-rich plasma (PRP) including high amounts of growth factors is introduced to clinical use rapidly. The aim of this study was to compare the effects of PRP and platelet-poor plasma (PPP) on healing of critical-size bone defects. Bilateral full-thickness, critical-size bone defects were created in the parietal bones of 32 rabbits, which had been studied in 4 groups. Saline, thrombin solution, PPP, and PRP were applied to the created defects before closure. Radiologic defect area measurement results at 0, 4, and 16 weeks were compared between the groups. In addition, densities of the newly formed bones at 16th week were studied. Histologic parameters (primary and secondary bone trabecula, neovascularization, and bone marrow and connective tissue formation) were compared between 4- and 16-week groups. More rapid decrease in defect size was observed in groups 3 and 4 than in groups 1 and 2, both in the 4th and 16th weeks. Newly formed bone densities were also found to be higher in these 2 groups. New bone formation was detected to be more rapid considering histologic parameters, in groups 3 and 4 at 4th and 16th weeks. Study demonstrates that PRP and PPP might have favorable effects on bone healing. Although we cannot reveal any statistical difference between these 2 substances considering osteoinductive potential, PRP group has demonstrated superior results compared with fibrin glue group. Higher platelet concentrations may expose beneficial effects of PRP.

Facial resurfacing in Xeroderma pigmentosum with monoblock full-thickness skin graft

A case of xeroderma pigmentosum with multiple skin tumors on the face that was treated with total excision and replacement of face skin except the eyelids with a monoblock full-thickness abdominal skin graft is reported. The quality and tumor-free features of the monoblock full-thickness skin graft in xeroderma pigmentosum are indicated. Despite the increased morbidity of the donor region, the radical surgical approach advocated here has improved the prognosis in the case reported.

Upper lateral cartilage fold-in flap: a combined spreader and/or splay graft effect without cartilage grafts.

Dorsal hump reduction almost always breaks the internal nasal valve and nasal obstruction is likely to occur postoperatively, unless reconstructed. One hundred eighty patients were operated using both open and closed rhinoplasty approaches. Upper lateral cartilages were meticulously separated from their junction with septum. Following bony and septal cartilaginous hump removal, upper lateral cartilages were folded inward. Either transcartilaginous horizontal mattress/simple sutures or perichondrial sutures were used depending of the desired width of the middle vault and the necessity for a splay-graft effect. In 7 patients unilateral, and in 1 patient bilateral, nasal synechia occurred and they were all treated under local anesthesia. All patients but 9 stated significantly improved nasal breathing. There was no inverted-V deformity or middle-vault narrowing observed. This technique is simple and physiologic, might be applicable for almost all primary rhinoplasty patients. Although it is possible with closed rhinoplasty approaches, it is easier with an open approach.