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Romed Meirer

Publications and source records attributed to Romed Meirer.

At least 19 recordsLinked to original sources
PubMed2005

Gene therapy with adenovirus-mediated VEGF enhances skin flap prefabrication.

We investigated the feasibility in rats of enhancing skin-flap prefabrication with subdermal injections of adenovirus-encoding vascular endothelial growth factor (Ad-VEGF). The left saphenous vascular pedicle was used as a source for vascular induction. A peninsular abdominal flap (8 x 8 cm) was elevated as distally based, keeping the epigastric vessels intact on both sides. After the vascular pedicle was tacked underneath the abdominal flap, 34 rats were randomly divided into three groups according to treatment protocol. The implantation site around the pedicle was injected with Ad-VEGF in group I (n = 10), with adenovirus-encoding green fluorescent protein (Ad-GFP) in control group I (n = 14), and with saline in control group II (n = 10). All injections were given subdermally at four points around the implanted vessel by an individual blinded to the treatment protocol. The peninsular flap was sutured in its place, and 4 weeks later, an abdominal island flap based solely on the implanted vessels was elevated. The prefabricated island flap was sutured back, and flap viability was evaluated on day 7. Skin specimens were stained with hematoxylin and eosin for histological evaluation. In two rats from each group, microangiography was performed to visualize the vascularity of the prefabricated flaps. There was a significant increase in survival of prefabricated flaps in the Ad-VEGF group compared to the control groups: Ad-VEGF, 88.9 +/- 6.1% vs. Ad-GFP, 65.6 +/- 9.4% (P < 0.05) and saline, 56.0 +/- 3.4% (P < 0.05). Sections from four prefabricated flaps treated with Ad-GFP revealed multiple sites of shiny deposits of green fluorescent protein around the area of local administration 1 day and 3 weeks after gene therapy. Histological examination done under high-power magnification (x400) with a light microscope revealed increased vascularity and mild inflammation surrounding the implanted vessel in all groups. However, we were unable to demonstrate any significant quantitative difference with respect to vascularity and inflammatory infiltrates in prefabricated flaps treated with Ad-VEGF compared with controls. Microangiographic studies showed increased vascularity around the implanted pedicle, which was similar in all groups. However, vascularization was distributed in a larger area in the prefabricated flaps treated with Ad-VEGF. In this study, the authors demonstrated that adenovirus-mediated VEGF gene therapy increased the survival of prefabricated flaps, suggesting that it may allow prefabrication of larger flaps and have the potential to reduce the time required for flap maturation.

Adenoviridae↗
PubMed2005

Sciatic nerve enlargement in the Klippel-Trenaunay-Weber syndrome.

The case of a 35-year-old woman with Klippel-Trenaunay-Weber syndrome (KTWS) showing clinical symptoms of a peroneal nerve lesion is presented. An immense nerve enlargement along most of the sciatic, peroneal and tibial nerve was found to be due to a lipoma arising from the epi- and perineurium. Treatment consisted of extensive microsurgical neurolysis and excision of the tumor resulting in decompression of the affected nerves. Although rare, a perineural lipoma should be kept in mind in patients with KTWS showing neurological abnormalities.

Adult↗
PubMed2005

Peroneal nerve palsy associated with knee luxation: evaluation by sonography--initial experiences.

OBJECTIVE: Traumatic knee dislocation needs immediate surgical repair to restore joint function. A concomitant traction injury of the peroneal nerve is reported to exist in up to 25% of cases and is often overlooked initially. In patients with major nerve lesions, immediate surgical nerve repair might be necessary to avoid irreversible loss of neural function. In the present study, we tried to evaluate whether sonography is a valuable tool for identification of nerve pathology that warrants surgical intervention. SUBJECTS AND METHODS: In this prospective study, both peroneal nerves in nine patients with one-sided peroneal nerve palsy after closed knee luxation and the peroneal nerves of 11 healthy volunteers were investigated with sonography. Using statistical analysis, we tried to define the comparability and significance of the findings. RESULTS: The mean cross-sectional area of healthy peroneal nerves in the genicular region was 0.18 cm2 (SD, 0.07 cm2). Impaired nerves were significantly discerned because of their increased cross-sectional area at the level of the injury (mean cross-sectional area, 0.7 cm2; SD, 0.46 cm2; p < 0.05). Identification of caliber changes and depiction of at least one nerve stump were found to be the most specific criteria for the definition of a major neural lesion. The ability of sonography to provide additional information about surrounding soft-tissue impairment (scar tissue and hematoma formation) proved helpful. CONCLUSION: Sonography allows radiologists to visualize neural and extraneural pathology and to define the exact level and extent of lesions. Thus, it may be a valuable adjunct in the decision of whether surgical intervention is necessary.

Adolescent↗
PubMed2004

Adenovirus-mediated transforming growth factor-beta ameliorates ischemic necrosis of epigastric skin flaps in a rat model.

BACKGROUND: Gene therapy has been recently introduced as a novel approach to treat ischemic tissues by using the angiogenic potential of certain growth factors. We investigated the effect of adenovirus-mediated gene therapy with transforming growth factor-beta (TGF-beta) delivered into the subdermal space to treat ischemically challenged epigastric skin flaps in a rat model. MATERIAL AND METHODS: A pilot study was conducted in a group of 5 animals pretreated with Ad-GFP and expression of green fluorescent protein in the skin flap sections was demonstrated under fluorescence microscopy at 2, 4, and 7 days after the treatment, indicating a successful transfection of the skin flaps following subdermal gene therapy. Next, 30 male Sprague Dawley rats were divided into 3 groups of 10 rats each. An epigastric skin flap model, based solely on the right inferior epigastric vessels, was used as the model in this study. Rats received subdermal injections of adenovirus encoding TGF-beta (Ad-TGF-beta) or green fluorescent protein (Ad-GFP) as treatment control. The third group (n = 10) received saline and served as a control group. A flap measuring 8 x 8 cm was outlined on the abdominal skin extending from the xiphoid process proximally and the pubic region distally, to the anterior axillary lines bilaterally. Just prior to flap elevation, the injections were given subdermally in the left upper corner of the flap. The flap was then sutured back to its bed. Flap viability was evaluated seven days after the initial operation. Digital images of the epigastric flaps were taken and areas of necrotic zones relative to total flap surface area were measured and expressed as percentages by using a software program. RESULTS: There was a significant increase in mean percent surviving area between the Ad-TGF-beta group and the two other control groups (P < 0.05). (Ad-TGF-beta: 90.3 +/- 4.0% versus Ad-GFP: 82.2 +/- 8.7% and saline group: 82.6 +/- 4.3%.) CONCLUSIONS: In this study, the authors were able to demonstrate that adenovirus-mediated gene therapy using TGF-beta ameliorated ischemic necrosis in an epigastric skin flap model, as confirmed by significant reduction in the necrotic zones of the flap. The results of this study raise the possibility of using adenovirus-mediated TGF-beta gene therapy to promote perfusion in random portion of skin flaps, especially in high-risk patients.

Adenoviridae↗
PubMed2004

The single-fascicle method of nerve grafting.

In this study a single-fascicle technique for neural deficits repair was evaluated using a rat sciatic nerve model. Twenty-four Lewis rats were divided into 4 groups: group 1, 1.5-cm deficit without repair; group 2, conventional autograft; group 3, large-fascicle autograft; and group 4, small-fascicle autograft. Nerve regeneration was evaluated by pin-prick and toe-spread tests. Nerve samples were estimated by histomorphometry. Group 1 presented no recovery. Groups 3 and 4 demonstrated significantly better pin-prick results compared with those from conventional repair. Histology revealed a significantly higher number of axons and myelin thickness in the small-fascicle (2.8 +/- 0.4 x 10(3) axons, 4.22 +/- 0.41 microm) and large-fascicle (5.1 +/- 1.7 x 10(3) axons, 4.62 +/- 0.28 microm) groups compared with the conventional autograft group (2.1 +/- 0.3 x 10(3) axons, 2.93 +/- 0.20 microm). The small-fascicle group had a significantly greater mean axon area (58.59 +/- 15.81 microm2) than the large-fascicle group (29.66 +/- 12.67 microm2) and the conventional group (25.35 +/- 7.52 microm2). In this study, peripheral nerve repair using a single-fascicle graft resulted in faster functional recovery and better morphometric outcome compared with conventional nerve repair.

Animals↗
PubMed2003

Morphology and topography of intraosseous ganglion cysts in the carpus: an anatomic, histopathologic, and magnetic resonance imaging correlation study.

PURPOSE: To assess the morphology, topography, frequency, and etiology of intraosseous carpal ganglions. METHOD: Two hundred and eighty formalin fixed cadaveric wrists (mean age 80.3 +/- 9.7 years, range 40 to 101 years) were radiographed. Fifty specimens suspicious for cyst-like bone lesions underwent magnetic resonance imaging (T1w and proton density-fat-saturated images, 1.5T). Dissection, articular surface assessment, and histological examination were performed. Cystic lesions with adjacent destruction of the hyaline cartilage were classified as degenerative and were excluded. RESULTS: In 27 of the 50 specimens, 48 ganglion cysts (GC) were found. Prevalence of GC was 9.6%. Of 48 intraosseous carpal GC, 41 (85%) were in a peripheral location; 27/48 (56%) were located at the palmar carpus. GC had a macroscopic and microscopic relationship to the insertion of degenerated ligaments. They developed near longitudinally orientated bone surfaces, which serve as insertion for ligaments and are exposed to tension loading. CONCLUSIONS: Unlike degenerative cysts, ganglion cysts do not erode the hyaline articular cartilage and almost always have a continuity with the capsular ligaments. Intraosseous carpal ganglion cysts are probably the result of mucoid degeneration of adjacent ligaments.

Adult↗
PubMed2003

Gracilis muscle split into two free flaps.

A case is presented in which the gracilis muscle was transversely split into two free flaps for coverage of two separate defects in a patient with a multi-segment fracture of the metatarsal bones and the ankle joint.

Adult↗
PubMed2003

Microsurgical management of the diabetic foot.

Allthough there has been dramatic progress in limb salvage in recent decades, management of nonhealing wounds in diabetic patients continues to present a dilemma for the reconstructive surgeon. However, the acceptance of free-flap resurfacing of diabetic foot ulcers has increased in recent years. This study reviews 10 microvascular free muscle flaps in nine patients over a mean follow-up period of 44 months. Five patients had evidence of peripheral vascular disease. There was one flap loss, and nine flaps were transferred successfully. No perioperative mortality was encountered. The operations required a long, costly hospitalization (average hospital stay was 40 days). Seven of eight patients whose flaps survived had complications related to the free-flap recipient site. These seven patients underwent 20 secondary surgical procedures due to arterial and venous thrombosis, partial necrosis of the skin grafts, minor local infections, and gangrene or necrosis of the remaining toes. In three patients, progressive ischemic necrosis of the remaining toes, with total survival of the flap, was attributed to a microvascular steal phenomenon. However, all eight patients whose flaps survived subsequently ambulated on their flaps. The study demonstrates that microvascular surgery may result in functional lower-extremity salvage in diabetic patients with foot wounds that are not treatable by local flaps or skin grafts, and are destined for amputation.

Adult↗
PubMed2003

A novel technique for peripheral nerve repair.

OBJECTIVE: To evaluate a novel technique for the repair of neural deficits using a single fascicle to bridge an injury in the rat sciatic nerve. STUDY DESIGN: Twenty-four male Lewis rats were divided into four groups as follows: group 1 (control group), 1.5-cm deficit without repair; group 2, conventional epineural repair with autografts (100% diameter); group 3, nerve repair with large single autograft fascicle (50% diameter); and group 4, nerve repair with small single autograft fascicle (25% diameter). METHODS: Nerve regeneration was evaluated at 3, 6, and 12 weeks by somatosensory evoked potential (SSEP) evaluation and standardized pin-prick and toe-spread tests. Nerve samples were harvested at 12 weeks and stained with toluidine blue to assess the total number of myelinated axons, axon area, and myelin sheath thickness. RESULTS: In group I, the pin-prick and toe-spread tests showed no response at 3, 6, and 12 weeks. Rats in groups 3 and 4 demonstrated significantly better pin-prick test results and a trend toward better toe-spread test responses compared with conventional-repair animals. The SSEP evaluations displayed nondiagnostic waves in rats in group 1 rats. There was no evidence that the other surgery groups differed significantly in median SSEP latencies. Histological evaluation revealed fibrosis in rats in group 1 rats and a significantly higher median number of axons and myelin thickness in the small single fascicle (1296 axons and 4.22 microm, respectively) and large fascicle (2682 axons and 4.62 microm, respectively) groups compared with the conventional autograft group (630 axons and 2.93 microm, respectively). The small fascicle group had a significantly greater mean axon area (58.59 micro m2) than the large fascicle (29.66 micro m2) and conventional autograft (25.35 micro m2) groups. CONCLUSIONS: Peripheral nerve repair using a single fascicle graft resulted in better functional recovery and morphometric outcome without a significant difference in electrophysiological status compared with conventional nerve repair. This technique may provide expanded sources of nerve autografts and alleviate the morbidity of harvesting peripheral nerves from multiple sites for individuals with extensive peripheral nerve injuries.

Animals↗
PubMed2003

Breast deformity in adolescence as a result of pneumothorax drainage during neonatal intensive care.

OBJECTIVE: During intensive care of newborns, a number of invasive techniques may be necessary for resuscitation. The margin of safety between effective treatment and iatrogenic damage is narrow. The objective of this study was to identify and discuss iatrogenic damage in females resulting from treatment of pneumothorax and to give neonatologists anatomically based advice for prevention. PATIENTS AND METHODS: We report 2 female patients (aged 13 and 16 years) born prematurely in whom breast deformity occurred caused by drainage of multiple pneumothoraces during intensive care. In an additional anatomic study, both hemithoraces of 5 newborn female cadavers (n = 10) were dissected to measure the extension of the breast tissue. RESULTS: The anatomic investigations in newborns demonstrate that breast tissue extends vertically from the second or third rib to the sixth rib and from close to the sternal edge medially, almost to the anterior axillary line laterally. CONCLUSION: Psychological distress and corrective surgery because of deformed breasts in adolescent girls who have undergone drainage of pneumothoraces as newborns can be avoided by placing the skin incision in the anterior axillary line, maintaining a distance of 4 to 5 cm inferior to the nipple, and by inserting the chest drain through the fifth or sixth intercostal space during neonatal treatment.

Adolescent↗
PubMed2002

Direct coaptation of extensive facial nerve defects after removal of the superficial part of the parotid gland: an anatomic study.

BACKGROUND: In the surgical repair of facial nerve paralysis, a tension-free end-to-end coaptation of the trunk or its branches with or without rerouting is functionally superior to grafting. Assuming that a lengthening of all branches of the parotid plexus can be attained by removal of the superficial part of the parotid gland and mobilization of the branches, we performed an anatomic study. METHODS: The parotid regions of 10 cadavers were dissected to investigate the length gained for the branches of the parotid plexus by this technique. Every branch at the upper and ventral border of the gland was marked by a surgical suture. After removing the superficial part of the parotid gland, the branches were cut at the suture, and the proximal stump was drawn toward the distal stump. The distance of the overlapping stumps was measured by means of an electronic gliding caliper. In addition, in five specimens only the trunk of the facial nerve was dissected by the same method, and the distance of the overlapping stumps was measured. RESULTS AND CONCLUSIONS: The results demonstrate that removing the superficial part of the parotid gland may be sufficient to enable direct coaptation without nerve grafting. Cut temporal or zygomatic branches with a gap of up to 15 mm and cut buccal or marginal mandibular branches with a gap of up to 23 mm can be bridged by mobilization of just the proximal stumps. This technique may also be used to bridge a 17-mm gap of the trunk of the facial nerve.

Aged↗
PubMed2002

Effect of chronic cyclosporine administration on peripheral nerve regeneration: a dose-response study.

An experimental study was conducted to investigate the effect of chronic cyclosporine A (CsA) administration with different doses on peripheral nerve regeneration. Forty adult male Lewis rats weighing 150 to 200 g were used. The right sciatic nerve was transected 1 cm distal to the sciatic notch, and a conventional end-to-end nerve coaptation was performed. According to the daily dose of subcutaneous CsA injections, animals were randomized into one control group and four experimental groups of 8 animals each (group I, control with no treatment; group II, 2 mg per kilogram CsA; group III, 4 mg per kilogram CsA; group IV, 8 mg per kilogram CsA; and group V, 16 mg per kilogram CsA). Daily injections of CsA were administered for 12 weeks by an investigator blinded to the different treatment groups. At 3, 6, and 12 weeks after nerve repair, motor recovery was evaluated by the toe spread test, and sensory recovery was measured using the pin-prick test and somatosensory evoked potentials (SEPs). Evaluations were performed by an investigator who was blinded to the treatment groups. At 12 weeks, sciatic nerve samples were harvested for histomorphometric analysis. Motor recovery was retarded regardless of CsA dose at each time point of evaluation. Sensory recovery was only delayed in the 16-mg-per-kilogram CsA treatment group at the 3 week follow-up. SEP results revealed significantly prolonged N2 and P1 latencies in all CsA treatments regardless of dose and time frame of evaluation compared with the control group (p < 0.05). Histomorphometric analysis demonstrated significantly reduced numbers of myelinated axons, reduced myelin sheath thickness, and reduced diameters in all CsA treatment groups compared with the control group (p < 0.05). Based on these findings in this experimental model of sciatic nerve, the authors conclude that CsA overall had direct deleterious effects on peripheral nerve regeneration as demonstrated by SEP, pin-prick test, toe spread test, and histomorphometric nerve analysis. These adverse effects seemed to be dose related for sensory recovery only at 3 and 6 weeks of CsA exposure after nerve repair. Motor recovery was affected negatively by short- and long-term CsA administration regardless of dose.

Animals↗
PubMed2002

Medial thigh lift free flap for autologous breast augmentation after bariatric surgery.

BACKGROUND: Massive weight loss following bariatric surgery frequently results in body contour deformities like ptotic and hypoplastic breasts, redundant abdominal tissue and loose skin especially in the medial thigh area. This redundant tissue can be used for breast augmentation in the case of hypertrophic ptotic breasts. METHOD: In 3 patients who underwent a vertical banded gastroplasty and consecutively lost more than 60% of their body weight, a breast augmentation with a transverse gracilis myocutaneous free flap was performed. RESULTS: Bilateral myocutaneous gracilis free flap breast augmentation resulted in an esthetic, pleasing result, with additional correction of the redundant skin from the medial thigh region. CONCLUSION: Autologous breast augmentation with a simultaneous medial thigh lift can be performed safely, after successful weight loss following bariatric surgery.

Adipose Tissue↗