A torsional strength comparison of vascularized and nonvascularized bone grafts

Comparisons of torsional strength are made on the ulnae from the forelegs of short haired hounds where a nonvascularized graft was performed on one leg and a vascularized graft performed on the other. By using the forelegs of a dog as the experimental model and microsurgical techniques, a vascularized bone segment was used to graft a five centimeter nonunion in one leg and at the same time a conventional bone graft was performed on a similar nonunion in the other leg. Similar segments of rib bone were used for each graft. Torsional strength data are shown for nine experimental animals. A successful method for mounting the bones for testing of torsional strength in a torsion machine is given. In each case for which the bones healed properly, the vascularized bone graft proved to be significantly stronger in torsion.     

Bronchoalveolar lavage in lung transplant patients.

Over a four-month period (November 1991-February 1991), six patients underwent lung transplantation for end-stage pulmonary disease. Twenty-four transbronchial biopsies with concurrent bronchoalveolar lavage were performed at regular intervals to evaluate acute graft rejection and/or infection. A study was performed to evaluate the role of lavage in the cytodiagnosis of acute pulmonary graft rejection. Histologic features of acute rejection were present in 11/24 biopsies (46%), consisting of perivascular and/or peribronchial lymphoid aggregates. Concurrent lavage findings were hyperplastic alveolar lining cells (one specimen, 9%), atypical lymphocytes (one specimen, 9%), and acute and chronic inflammation (nine specimen, 82%). Among the 13 lavages without concurrent histologic evidence of acute graft rejection (54%), atypical lymphocytes were present in one specimen (8%). The majority of the specimens (54%) showed a relative lack of inflammation. Two of the 24 lavages (8%) contained either Candida or cytomegalovirus (CMV), which were not present on the concurrent biopsy, and one biopsy contained CMV, which was absent on the lavage smear. Although a higher percentage of lavages with histologic evidence of acute graft rejection contained acute and chronic inflammatory cells as compared to lavages without concurrent histologic evidence of rejection, the cytodiagnosis of acute graft rejection on bronchoalveolar lavage is indeterminate.     

Roentgen stereophotogrammetric analysis methods for determining ten causes of lengthening of a soft-tissue anterior cruciate ligament graft construct

There are many causes of lengthening of an anterior cruciate ligament soft-tissue graft construct (i.e., graft+fixation devices+bone), which can lead to an increase in anterior laxity. These causes can be due to plastic deformation andor an increase in elastic deformation. The purposes of this in vitro study were (1) to develop the methods to quantify eight causes (four elastic and four plastic) associated with the tibial and femoral fixations using Roentgen stereophotogrammetric analysis (RSA) and to demonstrate the usefulness of these methods, (2) to assess how well an empirical relationship between an increase in length of the graft construct and an increase in anterior laxity predicts two causes (one elastic and one plastic) associated with the graft midsubstance, and (3) to determine the increase in anterior tare laxity (i.e., laxity under the application of a 30 N anterior tare force) before the graft force reaches zero. Markers were injected into the tibia, femur, and graft in six cadaveric legs whose knees were reconstructed with single-loop tibialis grafts. To satisfy the first objective, legs were subjected to 1500 cycles at 14 Hz of 150 N anterior force transmitted at the knee. Based on marker 3D coordinates, equations were developed for determining eight causes associated with the fixations. After 1500 load cycles, plastic deformation between the graft and WasherLoc tibial fixation was the greatest cause with an average of 0.8+/-0.5 mm followed by plastic deformation between the graft and cross-pin-type femoral fixation with an average of 0.5+/-0.1 mm. The elastic deformations between the graft and tibial fixation and between the graft and femoral fixation decreased averages of 0.3+/-0.3 mm and 0.2+/-0.1 mm, respectively. The remaining four causes associated with the fixations were close to 0. To satisfy the remaining two objectives, after cyclic loading, the graft was lengthened incrementally while the 30 N anterior tare laxity, 150 N anterior laxity, and graft tension were measured. The one plastic cause and one elastic cause associated with the graft midsubstance were predicted by the empirical relationships with random errors (i.e., precision) of 0.9 mm and 0.5 mm, respectively. The minimum increase in 30 N anterior tare laxity before the graft force reached zero was 5 mm. Hence, each of the eight causes of an increase in the 150 N anterior laxity associated with the fixations can be determined with RSA as long as the overall increase in the 30 N anterior tare laxity does not exceed 5 mm. However, predicting the two causes associated with the graft using empirical relationships is prone to large errors.     

Supernumerary regeneration in the large milkweed bug Oncopeltus fasciatus.

As an approach to the problem of pattern formation in the insect appendage, various graft combinations were studied in the legs of the large milkweed bug Oncopeltus fasciatus. Metathoracic legs of fourth instar larvae were amputated through the tibia within 24 hr after ecdysis and grafted back onto the stumps. The orientation of the graft was altered by rotation through 90 or 180° and/or by exchanging right and left stumps and grafts, yielding seven possible orientations in addition to the control. Many of these grafts resulted in the production of one or two supernumerary regenerates of the distal segments, which appeared at the graft junction after the second postoperative ecdysis. When two supernumerary regenerates resulted, one appeared to be produced from the stump and the other from the graft. When one regenerate was present, it appeared to be a composite of material produced from both the stump and the graft. In contrast to the results obtained in cockroaches, the external face of the leg appeared to be the only one capable of giving rise to a supernumerary regenerate.     

Surgical and Antimicrobial Treatment of Prosthetic Vascular Graft Infections at Different Surgical Sites: A Retrospective Study of Treatment Outcomes

Objective

Little is known about optimal management of prosthetic vascular graft infections, which are a rare but serious complication associated with graft implants. The goal of this study was to compare and characterize these infections with respect to the location of the graft and to identify factors associated with outcome.

Methods

This was a retrospective study over more than a decade at a tertiary care university hospital that has an established multidisciplinary approach to treating graft infections. Cases of possible prosthetic vascular graft infection were identified from the hospital''s infectious diseases database and evaluated against strict diagnostic criteria. Patients were divided into groups according to the locations of their grafts: thoracic-aortic, abdominal-aortic, or peripheral-arterial. Statistical analyses included evaluation of patient and infection characteristics, time to treatment failure, and factors associated specifically with cure rates in aortic graft infections. The primary endpoint was cure at one year after diagnosis of the infection.

Results

Characterization of graft infections according to the graft location did show that these infections differ in terms of their characteristics and that the prognosis for treatment seems to be influenced by the location of the infection. Cure rate and all-cause mortality at one year were 87.5% and 12.5% in 24 patients with thoracic-aortic graft infections, 37.0% and 55.6% in 27 patients with abdominal-aortic graft infections, and 70.0% and 30.0% in 10 patients with peripheral-arterial graft infections. In uni- and multivariate analysis, the type of surgical intervention used in managing infections (graft retention versus graft replacement) did not affect primary outcome, whereas a rifampicin-based antimicrobial regimen was associated with a higher cure rate.

Conclusions

We recommend that future prospective studies differentiate prosthetic vascular graft infections according to the location of the grafts and that rifampicin-based antimicrobial regimens be evaluated in clinical trials involving vascular graft infections caused by staphylococci.     

Complications of vascularized fibula graft for reconstruction of long bones

The clinical results and complications of the vascularized fibular graft for the reconstruction of various long bone defects were reviewed in 60 cases. Bony reconstruction was achieved in 57 of the 60 cases; however, various postoperative complications occurred in 54 percent of the cases. One case of arterial thrombosis of an anastomosed vessel and nine cases of venous congestion of the monitoring flap occurred in the early postoperative periods. The authors managed the nine cases of venous congestion of the flap conservatively, and all flaps survived. Partial necrosis of the flap was noted in eight of these nine cases, but additional surgical intervention was required in only four cases. Treatment included a gastrocnemius musculocutaneous flap in one case and a full-thickness skin graft in three cases. The vascularized fibula survived and bony fusion was achieved in all of these cases. The one case of arterial thrombosis resulted in graft failure due to a delay in the decision to perform a thrombectomy. Graft fracture occurred in 13 cases as the mechanical stress to the graft increased. In two cases of femoral reconstruction, graft fracture occurred during dynamization of the graft, despite the use of an Ilizarov external fixator. Correct alignment between the recipient bone and the external fixator is a prerequisite to preventing graft fracture. Vascularized fibular grafting offers the patient a great deal of benefit; however, this graft has a concomitant high risk of complications. Great attention to detail must be paid to prevent postoperative complications.     

The free tongue graft for correction of secondary deformities of the vermilion in patients with cleft lip

From January of 1985 to January of 1990, 31 patients with repaired cleft lip and secondary vermilion defects underwent 45 revisional procedures. A free tongue graft was utilized seven times in six patients (19 percent). Indications for its use were a V-shaped vermilion deficit or a "whistling" deformity associated with a sagittal vermilion deficiency and normal or insufficient lateral vermilion bulk. Of the seven free tongue grafts, none was lost. Three patients have required revisions, including repeat free tongue graft in one. Proper positioning of the graft along the free vermilion border has made color and texture match satisfactory. The free tongue graft is a simple and reliable means of transferring both vermilion bulk and surface mucosa. Introduction of the free tongue graft has eliminated the need for more cumbersome procedures, such as the Abbé flap or the tongue flap, in properly selected patients.     

Hook nail deformity repaired using a composite toe graft.

The hook nail deformity is caused by loss of fingertip bone and soft tissue. Healing can result in a volarly displaced distal nailbed and a tight tip with inadequate padding and a poor cosmetic appearance. A composite graft from the second toe placed beneath the released nailbed gives good support and improved pulp substance. The technique of the composite toe graft has been performed in nine patients. All grafts were 100 percent viable, but one patient required a second graft for additional tip bulk. There has been no donor-site morbidity in the follow-up of 1 month to 2 years.     

Migration of radio-opaque markers injected into tendon grafts: a study using roentgen stereophotogrammetric analysis (RSA)

An increase in anterior laxity following reconstruction of the anterior cruciate ligament (ACL) can result from lengthening of the graft construct either at the sites of fixation and/or between the sites of fixation (i.e., graft substance). Roentgen stereophotogrammetric analysis (RSA), which requires that radio-opaque markers be attached to the graft, has been shown to be a useful technique in determining lengthening in these regions. Previous methods have been used for attaching radio-opaque markers to the graft, but they all have limitations particularly for single-loop grafts. Therefore, the objective of this study was to evaluate injecting markers directly into the substance of a tendon as a viable method for measuring lengthening of single-loop graft constructs by determining the maximum amount of migration after cyclic loading. Tantalum spheres of 0.8 mm diameter were used as tendon markers. Ten single-loop tendon grafts were passed through tibial tunnels drilled in calf tibias and fixed with a tibial fixation device. Two tendon markers were inserted in one tendon bundle of each graft and the grafts were cyclically loaded for 225,000 cycles from 20 N to 170 N. At specified intervals, simultaneous radiographs were obtained of the tendon markers. Marker migration was computed as the change in distance between the two tendon markers parallel to the axis of the tibial tunnel. Marker migration had a root mean square (RMS) value of less than 0.1 mm. Because the RMS value indicates the error introduced into measurements of lengthening and because this error is negligible, the method described for attaching markers to single-loop ACL grafts has the potential to be useful for determining lengthening of single-loop ACL graft constructs in in vivo studies in humans.     

Crushed bone grafts and a collagen membrane are not suitable for enhancing cartilage quality in the regeneration of osteochondral defects--an in vivo study in sheep

Hyaline joint cartilage has only a limited potential for self-repair. Some of the published techniques for osteochondral defect therapy try to improve that potential. In this study, it was hypothesised that one of those surgical techniques, the crushed transplanted bone graft together with a collagen membrane, accelerates significantly the reconstruction of the subchondral bone plate and improves the mechanical and histological quality of repaired cartilage in osteochondral defects compared to an empty control defect. In order to test this hypothesis, defects were created in the left knee of 12 sheep and filled either with autologous crushed bone graft or left empty. The animals were sacrificed after 3 (n = 6) and 6 (n = 6) months. No differences were found either macroscopically or histomorphometrically between the bone graft and empty control defects. The biomechanical as well as the histological results of the bone graft defects were inferior to the control defects with inflammatory processes caused either by bone graft or membrane remnants. Based on the results in this sheep model, the filling of subchondral bone defects with compacted cancellous bone should be carefully reconsidered.     

Effects of monoclonal anti-H-2Ld and anti-H-2Dd alloantibodies in the immunological enhancement of skin grafts and neonatal heart grafts in the mouse

Three anti-H-2Ld and two anti-H-2Dd monoclonal alloantibodies were analyzed for their capacity to enhance skin graft and neonatal heart graft survival. Of two anti-H-2Ld antibodies with the same specificity but with different isotypes, IgG2a antibody 30-5-7S prolonged graft survival in a skin graft combination with an Ld difference, whereas IgM antibodies did not. A second IgG2a antibody, but with a specificity different from 30-5-7S, was ineffective on its own. However, when mixed with 30-5-7S, skin graft survival was augmented as compared with the prolongation by 30-5-7S alone. Enhancement by anti-H-2Ld antibodies was dependent on the extent of the H-2 graft barrier. It was abrogated on extension of the graft barrier to a D-end H-2 difference by using the B10.A----B10.BR combination. Also, anti-Dd antibodies, either alone or in combination with anti-Ld, were ineffective in this skin graft combination. By using the same graft combination but the less immunogenic neonatal heart graft model, anti-Ld antibodies were still ineffective, but both anti-Dd antibodies were able to enhance graft survival from 15 to 22 days. When mixed with anti-Ld antibody 30-5-7S, graft survival was augmented further to 30 days. These results indicate that two kinds of enhancing alloantibodies may be distinguished. One category interacts with immunodominant epitopes on H-2 molecules, but their effectiveness may be limited to a particular H-2 difference, because immunodominance may vary from one graft barrier to another. In the second category, antibodies are ineffective on their own but they are able to potentiate the effects of antibodies of the first kind. These allocations are relative, however, because they are dependent on the type of graft examined.     

How cyclic loading affects the migration of radio-opaque markers attached to tendon grafts using a new method: a study using roentgen stereophotogrammetric analysis (RSA)

An increase in anterior laxity following reconstruction of the anterior cruciate ligament (ACL) can result from lengthening of the graft construct in either the regions of fixation and/or the region of the graft substance between the fixations. RSA could be a useful technique to determine lengthening in these regions if a method can be devised for attaching radio-opaque markers to soft tissue grafts so that marker migration from repeated loading of the graft is limited. Therefore, the objectives of this study were 1) to develop a method for attaching radio-opaque markers to an ACL graft that limits marker migration within the graft, 2) to characterize the error of an RSA system used to study migration, and 3) to determine the maximum amount of migration and the time when it occurs during cyclic loading of ACL grafts. Tendon markers were constructed from a 0.8-mm tantalum ball and a stainless steel suture. Ten double-looped tendon grafts were passed through tibial tunnels drilled in bovine tibias and fixed with a tibial fixation device. Two tendon markers were sewn to one tendon bundle of each graft and the grafts were cyclically loaded for 225,000 cycles from 20 N to 170 N. At specified intervals, simultaneous radiographs were obtained of the tendon markers and a radiographic standard of known length. The bias and imprecision in measuring the length of the radiographic standard were 0.0 and 0.046 mm respectively. Marker migration was computed as the change in distance between the two tendon markers along the axis of the tibial tunnel. Marker migration was greatest after 225,000 cycles with a root mean square (RMS) value of less than 0.2 mm. Because the RMS value indicates the error introduced into measurements of lengthening and because this error is small, the method described for attaching markers to an ACL graft has the potential to be useful for determining lengthening of ACL graft constructs in in vivo studies in humans.     

The clopidogrel after surgery for coronary artery disease (CASCADE) randomized controlled trial: clopidogrel and aspirin versus aspirin alone after coronary bypass surgery [NCT00228423]

Background

Saphenous vein graft disease remains a major limitation of coronary artery bypass graft surgery. The process of saphenous vein intimal hyperplasia begins just days after surgical revascularization, setting the stage for graft atherosclerotic disease and its sequalae. Clopidogrel improves outcomes in patients with atherosclerotic disease, and is effective at reducing intimal hyperplasia in animal models of thrombosis. Therefore, the goal of this study will be to evaluate the efficacy of clopidogrel and aspirin therapy versus aspirin alone in the prevention of saphenous vein graft intimal hyperplasia following coronary artery bypass surgery.

Methods

Patients undergoing multi-vessel coronary artery bypass grafting and in whom at least two saphenous vein grafts will be used are eligible for the study. Patients will be randomized to receive daily clopidogrel 75 mg or placebo, in addition to daily aspirin 162 mg, for a one year duration starting on the day of surgery (as soon as postoperative bleeding has been excluded). At the end of one year, all patients will undergo coronary angiography and intravascular ultrasound assessment of one saphenous vein graft as selected by randomization. The trial will be powered to test the hypothesis that clopidogrel and aspirin will reduce vein graft intimal hyperplasia by 20% compared to aspirin alone at one year following bypass surgery.

Discussion

This trial is the first prospective human study that will address the question of whether clopidogrel therapy improves outcomes and reduces saphenous vein graft intimal hyperplasia following cardiac surgery. Should the combination of clopidogrel and aspirin reduce the process of vein graft intimal hyperplasia, the results of this study will help redefine modern antiplatelet management of coronary artery bypass patients.     

Metabonomics study of the acute graft rejection in rat renal transplantation using reversed-phase liquid chromatography and hydrophilic interaction chromatography coupled with mass spectrometry

Acute graft rejection is one of the most common and serious post complications in renal transplantation, noninvasive diagnosis of acute graft rejection is essential for reducing risk of surgery and timely treatment. In this study, a non-targeted metabonomics approach based on ultra performance liquid chromatography (UPLC) coupled with quadrupole time-of-flight mass spectrometry (MS) is used to investigate the effect of acute graft rejection in rat renal transplantation on metabolism. To collect more metabolite information both hydrophilic interaction chromatography and reversed-phase liquid chromatography were used. Using the partial least squares-discriminant analysis, we found that the change of metabonome in a sham-operated group and a non-graft rejection group had a similar trend, while that of the acute graft rejection group was clearly different. Several discriminating metabolites of the acute graft rejection were identified, including creatinine, phosphatidyl-cholines, lyso-phosphatidylcholines, carnitine C16:0, free fatty acids and indoxyl sulfate etc. These discriminating metabolites suggested that acute graft rejection in renal transplantation can lead to the accumulation of creatinine in the body, and also the abnormal metabolism of phospholipids. These findings are useful to understand the mechanisms of the rejection, it also means that a UPLC-MS metabonomic approach is a suitable tool to investigate the metabolic abnormality in the acute graft rejection in renal transplantation.     

Further evidence that epidermal growth factor enhances the intestinal adaptation following small bowel transplantation

Recent reports indicate that epidermal growth factor (EGF) plays a crucial role for graft adaptation in rat model of small bowel transplantation (SBT). The administration of EGF enhances intestinal cell proliferating rate and the recovery of mucosal structure. However, the effect of EGF on biological functions including glucose absorption in intestinal graft remains to be elucidated. SBT was performed in the two-step procedure. On the first step, intestinal graft (30-cm jejunum) from Brown Norway rats was exteriorized through abdominal wall as a Thiry-Vella loop in recipient Lewis rats for one week. On the second surgery (POD 7), recipient jejunum was replaced orthotopically by the graft, and transplanted rats were treated intraperitoneally with EGF or its vehicle for 3 days. Analyses of histology and biological functions in the graft were done at POD 14. EGF increased both levels of villus height and crypt depth in the graft of transplanted groups. EGF enhanced the glucose absorption as well as the induction of sodium glucose cotransporter 2- to 3-fold in transplanted groups. Further, EGF stimulated the activities of disaccharidase (maltase and sucrase) and the induction of dipeptide cotransporter. These results demonstrate that EGF enhances the structural and functional adaptation of intestinal grafts after SBT. EGF may be useful therapy for patients following intestinal transplantation.     

Effects of rhBMP-2 and osteopromotive membranes on experimental bone grafting.

A problem with using autogeneic bone for onlay grafting is its degree of incorporation and volumetric persistence. This study explored whether improved graft volumetric maintenance can be achieved by recombinant human bone morphogenetic protein-2 (rhBMP-2) and whether a combination of rhBMP-2 and osteopromotive membranes is advantageous in this respect. Unicortico-cancellous bone grafts were positioned below the temporal muscle bilaterally in 48 adult Lewis rats. The recipient bone was ground, and the grafted area was randomly treated according to one of eight different alternatives. Two doses of rhBMP-2 (4 microg/80 microl or 32 microg/80 microl buffer) in a collagenous carrier were tested, with or without coverage with expanded polytetrafluoroethylene membranes. As controls, membrane and carrier, alone or in combination, and onlay grafts only were used. The results were evaluated after 4 and 20 weeks by routine histologic examination and immunohistochemical labeling for various bone and cartilage matrix proteins. After 4 weeks, rhBMP-2-treated grafts showed complete integration, whereas for controls, only the membrane-alone group attained incorporation after 20 weeks. The combined treatment with high-dose rhBMP-2 and membrane demonstrated, as compared with the remaining rhBMP-2 groups, pronounced bone formation and less graft resorption, resulting in maintained or increased graft size. This was observed after 4 weeks, and the result remained at 20 weeks. Treatment with high-dose rhBMP-2 without membrane placement, in contrast, resulted in extensive resorption and graft size reduction at 20 weeks. Control groups showed less success in graft size persistence. It was concluded that a combination of high-dose rhBMP-2 and osteopromotive membranes had a synergistic effect, leading to rapid, complete graft integration and size maintenance. In the absence of a membrane, the protein seemed to accelerate the remodeling of the graft.     

Shear stress and pressure modulate saphenous vein remodeling ex vivo

Vein graft failure remains an important clinical challenge, but factors contributing to vein graft failure have not clearly been defined. We investigated the role of the mechanical environment in vein remodeling in an ex vivo perfusion system. Porcine saphenous veins were subjected to five different ex vivo hemodynamic environments, including one mimicking an arterial bypass graft, for one week in order to independently assess the effects of shear stress and pressure on vein remodeling. The extent of intimal hyperplasia decreased with culture under increasing shear stress, with veins cultured under the lowest levels of shear stress exhibiting the greatest ratio of intimal/medial area, 0.15+/-0.03, which was greater than that of fresh veins (0.06+/-0.01, p<0.05). All perfused veins displayed characteristics of both medial hypertrophy and eutrophic remodeling, with those veins cultured under elevated pressures showing greater increases in mass and area than those cultured under venous pressures. Medial area correlated with the average pressure under which veins were cultured (R2=0.95, p<0.001), with veins cultured under bypass graft conditions, which were exposed to the greatest pressure during the one week culture, exhibiting the largest medial area (1.69+/-0.15 mm2), which was significantly greater than that of fresh veins (1.08+/-0.05 mm2, p<0.05). However, pulsatility was not a necessary stimulus for medial growth, as increases in medial area were observed in culture conditions in which steady flow and pressure were present. Our results suggest that pressure and shear stress act independently to regulate vein remodeling, influencing changes in vessel size as well as the nature of the remodeling.     

Salvage of chronically exposed Gore-Tex vascular access grafts in the hemodialysis patient

Exposure and infection of a Gore-Tex vascular access graft often results in removal of the graft. Salvage of the graft is possible, however, with the use of well-vascularized muscle flaps. In 1982, Hodgkinson was the first to use a sublimis muscle flap to cover an exposed vascular access graft. We used the flexor carpi ulnaris and flexor digitorum superficialis to cover exposed Gore-Tex grafts in nine patients. The sublimis was used to cover distal graft exposures, and the longer flexor carpi ulnaris muscle was used to cover more proximal sites. Multiple exposures required both flaps or combinations of muscle flaps and local rotation flaps. Eight of nine chronically exposed grafts were salvaged using these techniques; a graft was removed from one patient because of diffuse unrecognized graft bed infection. Disability is minimized by using only part of the sublimis, and loss of the flexor carpi ulnaris is compensated by local muscles with similar actions. Vascular puncture can be continued during healing.     

Endovascular Repair of Arterial Iliac Vessel Wall Lesions with a Self-Expandable Nitinol Stent Graft System

Objective

To assess the therapeutic outcome after endovascular repair of iliac arterial lesions (IALs) using a self-expandable Nitinol stent graft system.

Methods

Between July 2006 and March 2013, 16 patients (13 males, mean age: 68 years) with a self-expandable Nitinol stent graft. A total of 19 lesions were treated: nine true aneurysms, two anastomotic aneurysms, two dissections, one arteriovenous fistula, two type 1B endoleaks after endovascular aneurysm repair, one pseudoaneurysm, and two perforations after angioplasty. Pre-, intra-, and postinterventional imaging studies and the medical records were analyzed for technical and clinical success and postinterventional complications.

Results

The primary technical and clinical success rate was 81.3% (13/16 patients) and 75.0% (12/16), respectively. Two patients had technical failure due to persistent type 1A endoleak and another patient due to acute stent graft thrombosis. One patient showed severe stent graft kinking on the first postinterventional day. In two patients, a second intervention was performed. The secondary technical and clinical success rate was 87.5% (14/16) and 93.8% (15/16). The minor complication rate was 6.3% (patient with painful hematoma at the access site). The major complication rate was 6.3% (patient with ipsilateral deep vein thrombosis). During median follow-up of 22.4 months, an infection of the aneurysm sac in one patient and a stent graft thrombosis in another patient were observed.

Conclusion

Endovascular repair of various IALs with a self-expandable Nitinol stent graft is safe and effective.     

Unpredictable growth pattern of costochondral graft.

Costochondral grafts have gained increasing popularity in reconstruction of the temporomandibular joint and condyle in children. This is a report on the long-term follow-up of eight adolescent patients who underwent reconstruction of the temporomandibular joint and ramus for correction of hemifacial microsomia or trauma-related temporomandibular joint ankylosis during varying periods of growth. Six patients had hemifacial microsomia, and two suffered from posttraumatic temporomandibular joint ankylosis. Average follow-up was 80.4 months. Four patients had excessive growth of the graft, one patient had suboptimal growth, and three patients had no growth. In addition, one patient had undergone four procedures for significant graft overgrowth. Based on this study and review of the literature, we have concluded that the growth pattern of the costochondral graft is extremely unpredictable, ankylosis is a common problem following a temporomandibular joint reconstruction with costochondral graft, and mandibular overgrowth on the grafted site can actually be more troublesome than the lack of growth. Furthermore, maxillary growth is proportionately influenced by vertical mandibular growth of the graft, while the horizontal maxillary growth is not altered. Ankylosis is a result of ossification of the cartilaginous portion and the three-dimensional graft overgrowth, aggressively extending beyond the cartilage graft boundary. Based on this study, we recommend that this procedure be performed only on severe deficiencies. Adequate amounts of soft tissue should be retained between the skull base and the graft, and we further recommend harvesting the graft from the fourth or fifth rib, which may reduce the potential for overgrowth.(ABSTRACT TRUNCATED AT 250 WORDS)