Biomedical subjects

M Ninković

Publications and source records attributed to M Ninković.

At least 19 recordsLinked to original sources

PubMed2006

Oxidative stress in the rats brain capillaries in sepsis--the influence of 7-nitroindazole.

As a part of blood-brain barrier, brain capillaries participate in pathophysiological events during systemic inflammation. We investigated the effects of 7-nitroindazole (7-NI), selective neuronal nitric oxide synthase (NOS) inhibitor, to oxidative status (OS) of brain capillaries. Adult Wistar rats were randomized at groups: control group (CG) (sham operated), sepsis group (GS) (cecal ligation and perforation with inoculation of Escherichia coli (ATCC 25922), 7-NI group (G7-NI), (30 mg/kg b/w i.p.) and 7-NI + sepsis group (G7-NIS), (7-NI was applied 30 minutes before operation). Lipid peroxidation index (LPI), nitrite concentration, superoxide dismutase (SOD) activity and superoxide anion (O2*-) content were determined 3, 6, 24 and 48 hour in each group. Cerebral capillaries were separated from non-vascular brain tissue using sucrose gradient. Compared to controls, LPI, nitrite and O2*- increased at SG. In the G7-NIS, LPI reached control values at the 24th and 48th hour, while nitrite were decreased at the 3rd and 24th hour, compared to controls. In the same group, O2*- decreased at the 3rd, 6th and 24th hour, although SOD showed variable activity. The systematic nNOS inhibition with 7-NI forces OS on early terms of sepsis, but lately it contributes to the normalization of OS in cerebral capillaries.

Animals↗

PubMed2002

Thoracodorsal artery perforator (TAP) flap: report of our experience and review of the literature.

We report our experience with the thoracodorsal artery perforator flap. Its use and pitfalls are critically highlighted, especially in terms of its application as an island flap. Publications on this recently described flap are scarce, possibly because it is rarely used as a result of the high level of skill needed in its preparation. In our hospital, we have used this flap twice as an island flap, both of which failed, and ten times as a free flap, one of which failed. Transfer as a free flap is a delicate procedure involving transmuscular vessel preparation; transposition as an island flap is limited by range. Based on our limited experience, we recommend this flap only in very selected cases. This procedure has to be performed by experienced microsurgeons, after training on cadavers, and after preoperative colour Doppler imaging to determine the precise location of the main perforators. Use of this perforator flap is indicated in cases where a long vascular pedicle for an appropriate free tissue transfer is necessary, and where aesthetic appearance and minimising donor-site morbidity are more important than a potentially high risk of failure.

Adolescent↗

PubMed2002

[Bilateral hand transplantation].

In March 2000 we performed a bilateral hand transplantation on a 47-year-old policeman who had lost both hands in a bomb accident. Although he was fitted with myoelectric prostheses, he kept investigating the possibility of hand transplantation. The ethical, surgical, medical, legal and human aspects of this special kind of reconstruction was discussed in a symposium in Vienna, and it was decided to go ahead with it if a suitable candidate presented. The operation was successful, the immunosuppressive regimen well-planned and carried out, the post-operative course without any remarkable events. Under intensive physical therapy, the patient gradually but steadily regained sensory and motor functions in his hands. Now, two years after the operation, the patient is practically independent in the activities of daily living and is able to work at his job.

Activities of Daily Living↗

PubMed2002

[Free microvascular transplantation of parts of the great toe for thumb reconstruction].

PURPOSE/BACKGROUND: A reconstructed thumb has to fulfil the function of opposition, pinch-grip, stability, sufficient length, sufficient sensibility, and painlessness. Next to pollicisation, these requirements can only be met satisfactory by the microvascular free great toe-to-hand transplantation. The goal of a thumb reconstruction is a compromise between an optimal functional and aesthetic outcome and a minimal morbidity of the donor site. METHOD AND CLINICAL MATERIAL: Depending on the extent of the traumatic thumb defect, not only the fibular part of the ipsilateral great toe but also its adjacent soft tissue and the first web space may be integrated into the vascularized transplant. The distal phalanx is reduced in width on its tibial side to integrate the second digital nerve to the transplant. The rest of the great toe is covered with the remaining sensible tibial flap. RESULTS: From 1993 to 1998, five male patients have been operated with the described method of partial great toe transfer and an additional deepening of the first web space. All reconstructions passed without complications. All patients present with a protective sensibility and a dynamic two-point discrimination between 8 and 15 mm. The average strength of the reconstructed thumb was 79 %, the strength of pinch-grip 90 % of the healthy thumb. CONCLUSION: Thumb reconstruction after traumatic amputation distal to the metacarpophalangeal joint can in our hands optimally be managed with free microvascular anastomosed parts of the great toe and its adjacent soft tissues.

Adult↗

PubMed2002

[The thoracodorsal artery perforator flap].

This report presents our experience with the thoracodorsal artery perforator flap. Its use and pitfalls are critically highlighted, especially the application of this flap as an island flap. Only few publications on this recently described flap are available, possibly because of the high level of skill needed in its preparation. In our hospital, this flap was twice used as an island flap, both of which failed, and ten times as a free flap one of which was a failure. Harvesting of this flap is a delicate procedure involving transmuscular vessel preparation, additionally transposition as an island flap is limited in range. Based on our limited experience, we can recommend use of this flap only in carefully selected cases. This procedure has to be performed by experienced microsurgeons, after training on cadavers, and after preoperative color Doppler imaging for determining the precise location of the main perforators. Only in cases, where a long vascular pedicle for an appropriate free tissue transfer is necessary, and where aesthetic appearance as well as minimizing donor-site morbidity are more important than a potentially higher failure rate, utilizing this perforator flap is justified.

Amputation Stumps↗

PubMed2001

[Viability monitor of free flaps in hypopharynx reconstruction].

Single-stage microvascular reconstruction of neck defects with jejunum or other free flaps are well established methods. However, these flaps usually are buried subcutaneously and viability surveillance is difficult. Alternatively to technical monitoring devices, we present a simple method using a "sentinel" part of the free jejunum flap transposed outside to the skin surface or sutured into the skin when using fasciocutaneous or myocutaneous flaps. Although this method is not new, it is rarely used. Compared to pure technical monitoring devices, it is easily performed and monitoring of buried free flaps especially in the neck region is reliable.

Esophageal Neoplasms↗

PubMed2001

Bladder reconstruction using a prevascularized capsular tissue seeded with urothelial cells.

PURPOSE: Recent advances in cell biology and tissue engineering have involved various avascular or acellular scaffolds with or without seeded cells. These techniques are frequently complicated by tissue necrosis, contracture and resorption. We used a vascularized matrix prelaminated with autologous cultured urothelial cells to reconstruct bladder wall defects. MATERIALS AND METHODS: A silicone block inserted into the right groin of 50 male Wistar rats directly superficial to the inferior epigastric vessels was used to induce capsule pouch formation. Urothelial cells harvested simultaneously and cultured were then suspended in fibrin glue and seeded into the newly formed capsule after removing the silicone block. After 1 week the prelaminated flap was transposed into a surgically created bladder wall defect. Experimental groups included rats with a urothelial cell seeded capsule pouch sacrificed at 1 and 4 weeks, respectively, after bladder reconstruction. In control rats scaffolds were treated only with fibrin glue or saline before transposition. RESULTS: Hematoxylin and eosin and immunohistochemical staining showed a continuous multilayered urothelial lining along the transposed prelaminated capsule flap in the experimental groups with better survival compared to controls treated only with fibrin glue (80% mortality) or saline (100% mortality). The surviving 3 control animals did not have a urothelial lining. CONCLUSIONS: Vascularized prefabricated flaps lined with culture derived urothelial cells were successfully used for bladder reconstruction in a rat model. The technique of prefabricating a vascularized scaffold lined with autologous urothelial cells may provide a method for future reconstruction of the genitourinary systems.

Animals↗

PubMed1999

One-stage reconstruction of defects in the hypopharyngeal region with free flaps.

Despite the almost universal poor prognosis, the reconstruction of combined cervical skin and hypopharyngeal defects after extensive resection of tumour should maintain optimal quality of life. From 1992 to 1996 we treated 10 patients with combined skin and hypopharyngeal defects with five fasciocutaneous free flaps, three myocutaneous latissimus dorsi free flaps, one myocutaneous VRAM (vertical rectus abdominis muscle) free flap and one free radial forearm flap. None of our flaps failed. The complications that required revision (one arterial bleeding, one arterial thrombosis, two fistula formations, one superficial wound dehiscence, one haematoma) occurred mainly in those patients having secondary reconstructions. After primary extensive oncological resection of these tumours reconstruction should be done in one stage. The primary reconstruction should provide sufficient pharyngeal lining, a satisfactory covering of cervical soft-tissue, and adequate functional rehabilitation. We have reviewed our experience and conclusions about the advantages, disadvantages, and current indications for different free flaps in the reconstruction of combined hypopharyngeal, cervico-oesophageal, and cervical skin defects.

Adult↗

PubMed1999

Free flap reconstruction of the foot.

Free flap reconstruction of the foot has been widely performed in the last 20 years, but choice of a free transferred substitute for the soft tissue of the particular defect remains controversial. The authors present a series of 77 free flaps to the foot performed in 68 patients during October 1976 and September 1997. Long-term follow-up ranged from 12 months to 18 years (median, 44.4 months). Seventy-three flaps were transferred successfully (95%). The indications for a specific flap depended on the localization and extension of the foot defect. In weight-bearing areas the authors favored the use of a muscle flap covered with a split-thickness skin graft; the latissimus dorsi muscle was used primarily. This study shows a lower ulceration rate in muscle flaps covered with split-thickness skin grafts than in fasciocutaneous flaps in weight-bearing areas (27% vs. 60%). In nonweight-bearing areas, fasciocutaneous flaps were the best choice. In this series, the lateral arm flap was applied most often. The authors recommend free fascial flaps (serratus fascial flap or radial forearm fascial flap) covered by split- or full-thickness skin grafts for coverage of the malleolar region as well as coverage of exposed tendons of nonweight-bearing regions. Proper tailoring of the flap and postoperative care are very important to maintain a result without ulceration, as is avoiding having the suture line cross a weight-bearing area. Tactile sensation does not seem to be essential.

Adolescent↗

PubMed1998

Flap salvage in a "flow-through" flap by manual thrombectomy plus thrombolytic therapy.

A delay in identifying incipient flap failure may inevitably lead to complete pedicle thrombosis and the no-reflow phenomenon. The authors report a clinical case of a lateral arm free flap that suffered complete pedicle thrombosis. They successfully salvaged this flap, a type C fasciocutaneous "flow-through" flap, by manually moving the thrombus from proximal to distal in the main flap artery. This freed the septofasciocutaneous upward-perforating branches, by smoothing and applying firm pressure to the vessel, combined with thrombolytic therapy. Their technique is offered as an alternative procedure for salvaging a failing flow-through flap.

Adult↗

PubMed1998

The lateral arm flap: review of 72 cases and technical refinements.

Between 1985 and 1995, 72 free lateral arm flaps (LAFs) were transferred in 68 patients. The main purpose of the reported study was to demonstrate a comprehensive follow-up and essential technical refinements: extension of the flap, shaping of a custom-designed flap, the "emergency" free flap, and sensible nerve coaptation. The effect of nerve coaptation vs. no nerve coaptation was investigated by measuring objective and subjective grades of sensibility at the recipient site. The outcomes of sensory flap reinnervation showed no significant advantages of one over the other technique. The second intention was to clarify discrepant anatomic descriptions concerning the nomenclature of the supplying blood vessels. Current anatomic investigations revealed that the main blood supply derives from the posterior radial collateral artery (anastomosing with the interosseous recurrent artery); blood supply via the anterior radial recurrent artery (anastomosing with the radial recurrent artery) has a secondary importance.

Adolescent↗

PubMed1998

Closure of complex defects in the chest wall with muscle flaps.

Aggressive treatment of thoracic malignancy may be complicated by complex defects in the chest wall. These may be associated with serious complications such as chronic infection, respiratory or cardiac failure, or major haemorrhage. Closure of the defect and restoration of the integrity of the chest wall is important for both functional and cosmetic reasons. Local flaps are often used, but may be inadequate or unavailable. Reconstruction with free flaps is better in these cases, as this provides as much abundant well-vascularised tissue as is required. We present 12 patients treated successfully for complex chest wall defects using various forms of local and free flap reconstruction. There were five complications, three healed spontaneously and two required secondary procedures before they healed.

Adult↗

PubMed1998

Reconstruction of a complex hypopharyngeal cervical defect with a single latissimus dorsi free flap.

Large, complex hypopharyngeal defects that include mucosa and cervical skin, and that result from debridement of orocutaneous fistulas secondary to failed repairs of laryngectomy defects, are difficult to treat, especially when previous irradiation has damaged adjacent tissues. We have found that such defects can be repaired sufficiently in one stage using a latissimus dorsi musculocutaneous free flap. The wound is debrided until only healthy tissue remains. The skin paddle of the free flap is then used to reconstruct the hypopharyngeal mucosal defect, whereas the muscular portion serves to cover any cervical tissue that remains exposed. A split-thickness skin graft is then placed over the muscle to complete the repair. The resulting reconstruction is free of excess bulk, has no radiation damage, is well vascularized, and has an acceptable appearance.

Adult↗

PubMed1998

Free innervated latissimus dorsi muscle flap for reconstruction of full-thickness abdominal wall defects.

Full-thickness abdominal wall defects continue to be a challenge for the reconstructive surgeon. The most frequently used reconstructive techniques are transfer of a pedicled, local abdominal flap or a distant flap from the thigh region. The purpose of this paper is to present a new approach to full-thickness abdominal wall reconstruction using an innervated free latissimus dorsi musculocutaneous flap. Four patients with large full-thickness abdominal wall defects underwent reconstruction with a free innervated latissimus dorsi muscle flap. In two patients, staged abdominal wall reconstruction was performed. Primary closure was first obtained with a skin graft. During the subsequent definitive reconstruction (with an innervated free latissimus dorsi muscle flap), this skin graft was not excised. Instead, deep dermabrasion of the skin graft was performed, leaving a residual dermal layer. This layer was then covered with a free innervated latissimus dorsi muscle flap. In these two cases, there was no need for the use of a prosthetic mesh. A single stage reconstruction was performed in the other two cases. After abdominal wall sarcoma resection, Prolene mesh was placed and subsequently covered with a free innervated latissimus dorsi muscle flap. There were no free flap failures. The average time of surgery was 4 hours, 50 minutes. The average hospital stay was 14 days. No significant complications occurred except for one donor site seroma. No hernias have occurred postoperatively. The mean follow-up was 21 months. Postoperatively, electromyographic testing was performed regularly in all patients to document reinnervation of the latissimus dorsi muscle flap. With reinnervation and intensive muscle training, the transplanted latissimus dorsi muscle offers enough contractile capacity and strength to adequately replace the function of the missing abdominal wall muscles. In complicated staged reconstructions, dermabrasion of the temporary skin graft allows for the use of a residual dermal layer as a fascia-like substitute to aid in the restoration of structural integrity. The combination of the dermal layer with an innervated free latissimus dorsi muscle provides a strong, vascularized fascial repair as well as an overlying vascularized soft-tissue coverage. In conclusion, adequate functional dynamic reconstruction of full-thickness abdominal wall defects is possible using an innervated free latissimus dorsi muscle flap. The reinnervated latissimus dorsi muscle is suitable for reconstitution of the missing functional and anatomic components of complex abdominal wall defects.

Abdominal Muscles↗

PubMed1998

New technique for scarless umbilical reinsertion in abdominoplasty procedures.

The most visible scar in the conventional abdominoplasty procedure or TRAM flap donor site closure is the scar around the reinserted umbilicus. In an attempt to increase the aesthetic outcome, the authors have introduced a new technique of umbilical reconstruction and reinsertion during abdominoplasty avoiding any paraumbilical scar, which results in a more natural appearance in that area. This new technique, potential pitfalls, and long-term results are reported.

Abdomen↗

PubMed1998

[Use of the internal mammary artery in reconstructive microsurgery in the thoracic region: anatomical-radiologic study].

In this study, the topographic anatomy and the diameter of the internal mammary (thoracic) vessels was investigated in regard to their potential as a recipient vessel in reconstructive microsurgery in the ventral thoracic region. Particularly for reconstruction of large thoracic wall defects as well as for female breast reconstruction with free tissue transplantation, these vessels seem to be suitable due to their location. We performed an anatomical study on 86 cadavers and a radiological investigation on 50 female patients and volunteers. We found a mean diameter on 50 female patients and volunteers. We found a mean diameter of 1.8 mm of the artery and 2.1 mm of the commitant vein at the level of the fourth rib, one to two centimeters parasternally. We conclude that the internal mammary vessels can serve as recipient vessels in reconstructive microsurgery in the ventral thoracic region at the level of the fourth rib or cranially. Hypothetically, free muscle flaps for the treatment of sternal osteitis, free fasciocutaneous flaps to replace presternal burn scars or appropriate flaps to fill up a funnel chest cavity subcutaneously may be anastomosed to the internal mammary vessels.

Adult↗

PubMed1997

[Infection prophylaxis in complex limb trauma through immediate definitive reconstruction via a free tissue transfer].

The concept of emergency free tissue transfer for severe extremity injuries represents a cutting-edge technology. We discuss our very positive results with this technique. The conceptual reasons for these favorable results, compared with conventional approaches, are also discussed. An initial, radical debridement is the most important part of the operation. This is then followed by osteosynthesis. The correct type of free tissue transfer is chosen according to the requirements of the soft tissue defect. Qualitatively better results with earlier definitive rehabilitation were achieved with free tissue transfer performed during the acute stage of limb wound treatment. The follow-up period ranged from 3 months to 8 years. We experienced neither flap loss, osteomyelitis, nor severe wound infection. Using the modern concept of emergency free tissue transfer, we reduced the rate of flap loss and associated morbidity while achieving a functionally improved reconstruction.

Adolescent↗

PubMed1997

Seroma as a common donor site morbidity after harvesting the latissimus dorsi flap: observations on cause and prevention.

This prospective study reveals that the incidence of seroma formation after harvesting the latissimus dorsi muscle by scalpel is reasonably moderate. This incidence is lower when the resulting skin flaps are tacked to the underlying structures with resorbable sutures. In contrast, electrocautery dissection shows a significantly much higher rate of seroma formation, probably because of thermal injury of the wide fascial wound layers or the subcutaneous fat tissue. Fifty-eight patients were distributed among three groups. Within each group a specific way of latissimus dorsi muscle harvesting and donor site treatment was accomplished. The group of scalpel dissection and skin flap fixation to the underlying layers with additional tacking sutures shows the lowest rate of seroma formation (9.1%, N = 2) due to the avoidance of shearing effects. A clearly higher incidence is present in the group of scalpel dissection without tacking sutures (38.1%, N = 8), whereas seromas most frequently result after electrocautery dissection without skin flap fixation (80.0%, N = 12).

Cysts↗