Posterior Graft Research Articles

Correlation between radiological and clinical findings after anterior cruciate ligament reconstruction

In the last two decades, the gold standard for anterior cruciate ligament reconstruction is the bone-patellar tendon-bone graft procedure. Correct position of the bone-patellar tendon-bone graft significantly affects the postoperative knee stability. The aim of this study was to establish if and how clinically measured knee stability is associated with radiographic position of bone-patellar tendon-bone graft in the femoral and tibial bones. The prospective study included 39 patients, 30 men and 9 women. We analyzed and compared results of clinical and radiographic examinations prior to and 2 years following surgery. The mean arthrometric difference between the anterior tibial movement prior to surgery was 11.2 mm and 2.4 mm (p < 0.05) after surgery. The preoperative Tegner and Lysholm score was 1.49, and postoperative 8.23 (p < 0.05). The preoperative Lysholm-Gillquist scale was 51.56 and postoperative 97.74 (p < 0.05). The International Knee Documentation Committee (IKDC) scores were as follows: grade A in 32 patients (84.6%), grade B in 5 patients (12.8%), and grade C in 1 patient (2.6%). By comparison of IKDC scores and radiographic parameters (M1-M10) of anterior-posterior and profile views, a statistical significance was found only between IKDC and M9 index (sagittal femoral index OR'/RR' x 100). By using bone-patellar tendon-bone grafts, it is not possible to entirely achieve anatomical positions. Correct graft position within the bone tunnels is of great significance concerning knee stability after anterior cruciate ligament reconstruction. Correlation between radiological and clinical findings after anterior cruciate ligament reconstruction in our 39 patients shows that only the position of the graft affects the clinical outcome. Posterior graft location provides better clinical outcome and knee stability. On the other hand, anterior location is associated with worse postoperative IKDC scores, unstable knee and worse clinical outcome.

Effects of Irradiation on Nerve Graft Vasculature

Increasing doses of therapeutic irradiation are known to impair nerve regeneration after grafting. One possible factor is the effect of irradiation on the endoneurial vasculature. This study investigates the effects of postoperative irradiation on the size, number, and cross-sectional area of endoneurial vessels in the rat posterior tibial nerve graft model. Sixty-five Sprague-Dawley rats underwent 1.5-cm interposition grafts to the tibial nerve. Postoperatively, they were assigned to one of five groups. The animals in Group 1 were unirradiated controls. Groups 2 to 5 received postoperative irradiation in the amounts of 46, 66, 86, and 106 Gy, respectively. One hundred and twenty days after grafting, sections of the proximal, grafted, and distal nerve were harvested and analyzed with digital morphometry. Statistical analysis of the average vessel area, number of vessels, and total vascular area was performed. The grafted segments of Groups 4 and 5 and the distal segments of all irradiated groups showed a statistically significant decrease in the number of vessels, compared to controls. The average size of the vessel was smaller in the proximal segment of the irradiated groups, compared to controls. There was no difference in size in either the grafted or distal segments of the irradiated groups, compared to controls. The observed changes in the endoneurial vasculature resulted from both the action of regeneration and the effects of irradiation. The irradiation effects appear to be dose-dependent.

Surgical Treatment of Neck Hyperextension in Myopathies

Neck hyperextension occurs in relation to several myopathies. It is a progressive increase of lordosis associated with a limitation in flexion of the cervical spine, forcing the patient to assume awkward compensatory postures to maintain balance and level vision. We evaluated operative complications, degree of correction, achievement of a solid arthrodesis, maintenance of the correction, and clinical assessment of seven patients. All had surgery in which the interspinous processes between C2-C7 were opened in a posterior approach and bone graft wedges driven into them to maintain the correction. The mean age of patients at the time of surgical intervention was 16.5 years (range, 10-28 years). The average followup was 10.4 years (range, 2.4-16.5 years). No major surgical complications occurred. After surgery, the average angle between C2-C7 in neutral position had decreased from 50.7 degrees (range, 40 degrees -70 degrees ) to 21.4 (range, 2 degrees -50 degrees ). The range of motion in the C1-C2 joint remained unaffected, whereas it decreased in C2-C7 from 33.5 degrees (range, 15 degrees -64 degrees ) to 1.8 degrees (range, 0 degrees -8 degrees ). A solid arthrodesis was achieved in all patients The followup showed significant clinical improvement of posture in all patients. The operating technique used proved to be safe and effective.

Posterior mini-incision technique for hamstring anterior cruciate ligament reconstruction graft harvest

This study presents a new approach to hamstring graft harvest. The hypothesis tested was that this approach, the posterior mini-incision technique, would result in (1) consistent semitendinosus (ST) and gracilis (Gr) tendon identification, (2) consistent identification and sectioning of the accessory semitendinosus tendon, (3) virtual elimination of the risk of cutting hamstring grafts short, (4) excellent safety, and (5) a small anterior incision with excellent cosmesis. Surgical technique. Two-hundred three consecutive primary hamstring anterior cruciate ligament reconstructions were performed in skeletally mature patients using this technique. Of these, 185 were located and 175 were clinically evaluated. Follow-up was 24 to 113 months. Ninety patients completed a brief cosmesis questionnaire. Seven fresh-frozen knees were dissected. The locations of the ST and Gr tendons were identified in the popliteal fossa along a medial-to-lateral axis for purposes of incision placement. The location of the accessory ST was documented and the distance from the posterior incision to the popliteal artery was measured. There were no complications referable to graft harvest. No tendon was cut short. The posterior graft harvest mini-incision and the anterior tibial fixation/tibial tunnel mini-incisions were each usually about 1 inch in length. Cosmesis evaluation showed that 80% of patients thought their incisions looked better than the incisions of others they had seen who had had anterior cruciate ligament reconstruction. None thought them worse. Cosmesis was important to a majority of patients. The posterior mini-incision technique facilitated safe, rapid hamstring graft harvest and virtually eliminated the risk of cutting tendons short. Cosmesis was excellent, and was important to patients. Level V.

A Biomechanical Study of Unilateral Posterior Atlantoaxial Transarticular Screw Fixation

The purpose of this study was to investigate the fixation of C1-C2 instability with the use of a unilateral screw. Transarticular screw placement across C1-C2 may be contra-indicated in up to 20% of specimens on at least one side because of anatomic variations or other pathological processes. Hence the current study looks into unilateral screw fixation of C1- C2 instability. Eight cervical spine specimens, C1 through C5, were harvested from fresh human cadavers (4 male and 4 female) of average age 67 years (54-80). C1 and C2-C5 vertebrae were potted to allow motion only at the C1-C2 articulation. Cutting the transverse ligament on both sides of the odontoid and the tectorial membrane destabilized the specimens. Transarticular screw fixation of C1-C2 was performed in a manner similar to the technique described by Magerl. The stability was tested after fixation with one transarticular screw together with a posterior graft and wire. Placement of the screw was randomized, resulting in half the specimens receiving screws on the right side and the remaining half on the left side. The stiffness of the C1-C2 articulation was tested in rotation, lateral bending, flexion, and anterior translation in random order. The rotational stiffness was 1.44 +/- 0.44 N-m/deg, while lateral bending stiffness values were 2.33 +/- 1.14 N-m/mm (right bending) and 2.81 +/- 1.36 N-m/mm (left bending). The stiffness value in flexion was 0.813 +/- 0.189 N-m/mm and in translation 67.1 +/- 25.1 N/m. It was found that stability after unilateral transarticular screw fixation was less than that previously reported after bilateral transarticular screw fixation, but similar to that found with modified Brooks posterior wiring, which has been shown to provide better stability than other posterior wiring methods, and fusion rates of 96% have been reported. We concluded that C1-C2 unilateral posterior transarticular screw fixation with supplemental posterior graft and wiring would confer adequate stability in cases where bilateral screw placement is contraindicated.

The use of posterior cricoid grafting in managing isolated posterior glottic stenosis in children.

To review our experience using posterior cricoid grafts to manage pediatric patients with isolated posterior glottic stenosis (PGS). Retrospective review over a 12-year period. Tertiary care pediatric hospital. All patients with isolated PGS treated between 1990 and 2002, in whom PGS was the dominant airway lesion and laryngotracheoplasty was required. Patients with concomitant vocal cord paralysis, a history of posterior laryngeal clefting, a Bogdasarian type I stenosis, or subglottic stenosis worse than grade I were excluded. Cause, operative intervention, decannulation rate, failure rate, and requirement for secondary procedures. A total of 29 patients ranging in age from 2 to 8 years were treated (21 with a history of prolonged intubation and 8 with a history of laryngeal trauma). Twenty patients had tracheotomies in place at the time of airway reconstruction and the remainder had stridor. Costal cartilage was the preferred graft material and was used in 27 patients. Six patients were referred with a diagnosis of bilateral vocal cord paralysis, but on evaluation were found to have PGS and mobile vocal cords. In 12 patients, repair was accomplished in a single-stage procedure; a suprastomal stent was placed in 17 patients. Overall decannulation rate was 97%, though a second procedure was required in 4 patients. One patient remained tracheotomy dependent; 4 had poor voice, including 2 with a history of laryngeal fracture; and 2 had late arytenoid prolapse. Isolated PGS in children is effectively managed with costal cartilage grafting of the posterior cricoid. This series has seen an evolution in management, with shorter stenting periods, placement of flanged posterior grafts without sutures, and graft placement without complete laryngofissure.

Revision single-stage laryngotracheal reconstruction in children.

In this report, we discuss indications, technique, outcome, and complications of revision single-stage laryngotracheal reconstruction (SSLTR), formulate guidelines to avoid or prevent procedure failure, and establish a protocol for the management of procedure failure. We retrospectively reviewed the charts of 122 patients between the ages of 8 months and 9 years who underwent SSLTR between January 1992 and September 2001 in 2 tertiary care children's medical centers in different cities and assessed the outcomes of patients who underwent revision SSLTR. A total of 122 patients underwent SSLTR, of whom 48 patients underwent anterior and posterior grafting. Of the 122 patients, 13 had revision SSLTR; 8 of these 13 underwent the initial laryngotracheal reconstruction at another institution. Five patients had anterior grafting laryngotracheal reconstruction without stenting, 7 had anterior and posterior grafting with 1 to 21 days of endotracheal intubation, and I had cricotracheal resection and anastomosis. Of the 13 patients, 5 had anterior wall or graft collapse (grade IV stenosis), 4 had subglottic stenosis (grade IV), 2 had circumferential subglottic stenosis (grade III), and 2 had subglottic and glottic stenosis (grade IV). The overall success rate for all patients was 86% (105 of 122). The success rates for the 122 patients were as follows: anterior grafting, 100%; anterior and posterior grafting, 83% (40 of 48); and revision cases, 70% (9 of 13). We conclude that laryngotracheal reconstruction with a costal cartilage rib graft should be considered the procedure of choice for the management of subglottic stenosis. We believe that patients in whom the first procedure fails should have a high chance of success with revision SSLTR if strict guidelines and protocols are followed.

Repair of chronic subglottic stenosis with autogenous thyroid cartilage.

Chronic subglottic stenosis continues to be a difficult management problem. Conservative management with bougienage, laser therapy, mitomycin-C, and/or steroid injections frequently fails. Definitive resection of the subglottis with thyrotracheal anastomosis has increased in popularity, but carries significant operative risks and postoperative complications. In the past 9 years, we have used a modification of a technique to successfully widen the subglottis, which we previously published 20 years ago. By a laryngocricotracheofissure approach, the cricoid cartilage is split vertically, both anteriorly and posteriorly. Cartilage grafts, obtained from the upper thyroid laminae anteriorly, are inserted in these splits. The posterior graft is fixed in place with specially designed pins, which improves graft fixation by adding rigidity and shortens the procedure. The repair is held in place for 3 to 4 weeks with either a silicone T tube or a conforming laryngeal stent. The charts of 21 consecutive patients treated with open repair of chronic subglottic stenosis were reviewed. The overall decannulation rate was 95%. We conclude that autogenous grafting is a useful tool in the treatment of chronic subglottic stenosis. Posterior cartilage graft fixation with our pin technique offers a significant advantage over suture fixation by improving graft stability and decreasing operative time, and has a high rate of decannulation.

Nonmechanical posterior lamellar keratoplasty using the femtosecond laser (femto-plak) for corneal endothelial decompensation

Purpose To assess the potential of a short pulsed laser to cut a posterior graft and bed for posterior lamellar keratoplasty (PLAK). Design Experimental study. Methods Using the laser FEMTEC (20/10 Perfect Vision, Heidelberg, Germany), posterior lamellar dissections (wave length approximately 1 μm, pulse energy < 10 μJ, spot size <10 μm, repetition rate 12.5 kHz, 6-mm–7 mm diameter, 31 s and 90 s) were performed in 18 freshly enucleated porcine eyes and 10 human donor corneas starting from the anterior chamber and ending with the lamellar bed. Results Before removal, 50-μm to 500-μm-thick flaps were delineated by partly confluent gas bubbles (maximum 2-mm long) with minute tissue bridges (typically 5- to 10-μm) in between. Scanning electron microscopy displayed smooth cut surfaces and rectangular corners with minor remaining tissue bridges (approximately 5 μm). By transmission electron microscopy, the cut edges were lined by a delicate, electron-dense layer (5 nm–10 nm in width) and essentially normal adjacent collagen fibers. Conclusions Femtosecond laser technology seems to offer a promising approach to minimally invasive posterior lamellar keratoplasty (femto-PLAK) through small tunnel incisions in corneal endothelial diseases.

Posterior cartilage graft in single-stage laryngotracheal reconstruction

Purpose Single-stage laryngotracheal reconstruction (LTR) has gained popularity during the past decade, but few reports discuss posterior grafting. We assessed the indications, treatment, complications, and outcomes for patients who underwent this procedure. Methods We reviewed the charts of 120 pediatric patients who underwent LTR at LeBonheur Children’s Medical Center or the University of Mississippi Medical Center between January 1992 and September 2000. We identified and evaluated those who had undergone single-stage anterior plus posterior cartilage rib graft reconstruction during this period. Results Of 120 patients, 56 had anterior graft procedures, and 46 had anterior plus posterior cartilage rib graft reconstruction. The 46 patients included 26 boys and 20 girls (age range, 18 months to 9 years; follow-up periods, 3 months to 6 years). Twenty-one of 46 had circumferential grade III stenosis, 14 had grade IV stenosis, 4 had bilateral vocal cord paralysis, 4 had posterior glottic and subglottic stenosis, and 3 had laryngeal cleft. Eleven of 46 patients had previous procedures and required revision LTR. All 46 patients underwent single-stage reconstruction with temporary stenting using an endotracheal tube for 10 to 24 days; 4 failed required replacement of the tracheotomy tube, and 8 required reintubation after the first extubation. The overall decannulation success rate was 83% (38 of 46). Conclusions LTR is the procedure of choice for the surgical management of subglottic stenosis. Although use of a posterior rib graft is technically demanding and requires extensive experience, good results can be obtained when the guidelines are followed.

Failure of cyclosporin a to rescue peripheral nerve allografts in acute rejection.

Prevention and control of graft rejection remain essential in the investigation of peripheral nerve allotransplantation. Although use of cyclosporin A (CsA) has been shown to suppress successfully the rejection of nerve allografts, limited information exists concerning use of this drug to arrest rejection in progress, and thereby effect salvage of these grafts. The aim of this study was to determine the efficacy of CsA in the treatment of ongoing acute rejection of peripheral nerve allografts. Buffalo rats received posterior tibial nerve grafts from either Lewis or Buffalo donor animals and were divided into five groups: group 1 received isografts and no CsA treatment (n = 8), group 2 received allografts with continuous CsA therapy (n = 10), group 3 received allografts with no treatment (n = 7), group 4 received allografts with initiation of CsA therapy delayed until 3 weeks after the procedure (n = 11), and group 5 received allografts with an interrupted course of CsA (n = 15). All grafts were harvested at 10 weeks. Histomorphometric analysis demonstrated comparable nerve regeneration in groups 1 and 2 and good regeneration in group 3 animals, despite cellular infiltrate suggestive of rejection. At 3 weeks after surgery, group 4 animals showed early rejection and significantly less neuroregeneration than positive controls at 10 weeks after delayed initiation of CsA therapy. Finally, group 5 animals showed early regeneration at 3 weeks but significantly lesser regeneration by 10 weeks after interruption of therapy. In this experimental protocol, CsA was ineffective in rescuing histologically proven rejection in progress.

Laryngeal electromyography in the management of vocal cord mobility problems in children.

To evaluate the efficacy and clinical usefulness of laryngeal electromyography (EMG) in the evaluation and management of vocal cord mobility problems in children; and to determine the ability of laryngeal EMG to differentiate vocal fold fixation versus paralysis. Case-series review of 8 children with vocal cord immobility who underwent laryngeal EMG. Eight children with bilateral vocal fold immobility underwent microlaryngoscopy and electromyography. Bipolar concentric needle electrodes were used and implanted separately into both posterior cricoarytenoid (PCA) and both thyroarytenoid (TA) muscles. EMG activity was recorded during spontaneous ventilation under a light plane of anesthesia with propofol. EMG activity was correlated with the phases of the respiratory cycle. Three patients had evidence of normal EMG activity with PCA activity peaking during early inspiration. Maximal TA activity occurred expiration. These patients were assumed to have vocal fold fixation. Two of these 3 patients underwent laryngotracheoplasty (LTP) with posterior glottic expansion with costal cartilage. One is being considered for LTP in the future. Five patients had abnormal EMG activity and remain tracheotomy-dependent. Four patients exhibited synkinetic activity with peak PCA activity during expiration and peak TA activity during expiration. Two patients had both fixation and unilateral vocal cord paralysis. One was successfully decannulated after posterior graft LTP and the other is planned for the future. Electromyography, which differentiates paralysis from fixation, is a useful diagnostic tool in the evaluation of children with vocal cord immobility.

A Biomechanical Comparison of Modern Anterior and Posterior Plate Fixation of the Cervical Spine

A biomechanical study was designed to assess relative rigidity provided by anterior, posterior, or combined cervical fixation using cadaveric cervical spine models for flexion-distraction injury and burst fracture. To compare the construct stability provided by anterior plating with locked fixation screws, posterior plating with lateral mass screws, and combined anterior-posterior fixation in clinically simulated 3-column injury or corpectomy models. Anterior plating with locked fixation screws is the most recent design and is found to provide better stability than the conventional unlocked anterior plating. However, there are few data on the direct comparison of biomechanical stability provided by anterior plating with locked fixation screws versus posterior plating with lateral mass screws. Biomechanical advantages of using combined anterior-posterior fixation compared with that of using either anterior or posterior fixation alone also have not been well investigated yet. Biomechanical flexibility tests were performed using cervical spines (C2-T1) obtained from 10 fresh human cadavers. In group I (5 specimens), one-level, 3-column injury was created at C4-C5 by removing the ligamentum flavum and bilateral facet capsules, the posterior longitudinal ligament, and the posterior half of the intervertebral disc. In group II (5 specimens), complete corpectomy of C5 was performed to simulate burst injury. In each specimen, the intact spine underwent flexibility tests, and the following constructs were tested: (1) posterior lateral mass screw fixation (Axis plate) after injury; (2) polymethylmethacrylate anterior fusion block plus posterior fixation; (3) polymethylmethacrylate block plus anterior (Orion plate) and posterior plate fixation; and (4) polymethylmethacrylate block plus anterior fixation. Rotational angles of the C4-C5 (or C4-C6) segment were measured and normalized by the corresponding angles of the intact specimen to study the overall stabilizing effects. Posterior plating with an interbody graft showed effective stabilization of the unstable cervical segments in all loading modes in all cases. There was no significant stability improvement by the use of combined fixation compared with the posterior fixation with interbody grafting, although combined anterior-posterior fixation tended to provide greater stability than both anterior and posterior fixation alone. Anterior fixation alone was found to fail in stabilizing the cervical spine, particularly in the flexion-distraction injury model in which no contribution of posterior ligaments is available. Anterior plating fixation provided much greater fixation in the corpectomy model than in the flexion-distraction injury model. This finding suggests that preservation of the posterior ligaments may be an important factor in anterior plating fixation. This study showed that the posterior plating with interbody grafting is biomechanically superior to anterior plating with locked fixation screws for stabilizing the one-level flexion-distraction injury or burst injury. More rigid postoperative external orthoses should be considered if the anterior plating is used alone for the treatment of unstable cervical injuries. It was also found that combined anterior and posterior fixation may not improve the stability significantly as compared with posterior grafting with lateral mass screws and interbody grafting.

Single-stage laryngotracheal reconstruction in children: A review of 200 cases

Objective: We reviewed our experience with pediatric single-stage laryngotracheal reconstruction (SSLTR) to identify factors that affect postoperative outcomes, including the need for reintubation and tracheostomy. Study Design: Retrospective chart review was done. Results: In total, 190 children underwent 200 SSLTRs; 29% were reintubated, and 15% required postoperative tracheostomy. Currently, 96% are decannulated. The use of anterior and posterior costal cartilage grafting, age less than 4 years, sedation for more than 48 hours, a leak pressure around the endotracheal tube at greater than 20 cm H 2O, and moderate/severe tracheomalacia significantly increased the rate of reintubation. The duration of stenting did not affect outcomes. Children with anterior and posterior grafts and those with moderate or severe tracheomalacia were more likely to need a postoperative tracheostomy. Conclusion: SSLTR can be effective for the treatment of pediatric laryngotracheal stenosis. Diligent preoperative assessment of the patient and the patient's airway and close postoperative care are important to the success of this operation. (Otolaryngol Head Neck Surg 2000;123:430-4.)

Enzimas miocárdicas na cirurgia de revascularização sem circulação extracorpórea

INTRODUÇÃO: A cirurgia cardíaca com o coração batendo está sendo cada vez mais utilizada para minimizar danos cerebrais, renais e outros. Porém, a incidência de infarto nos períodos per e pós-operatório e seu efeito a longo prazo, especialmente quando esta técnica é comparada às tradicionais, ainda não foi totalmente esclarecida. CASUÍSTICA E MÉTODOS: Um estudo retrospectivo de 303 pacientes (122 sem CEC, 181 com CEC) foi realizado de fevereiro/97 a fevereiro/99. Dosagens de CK-MB e eletrocardiogramas foram avaliados nos períodos per e pós-operatório, troponina T (TnT) foi medida no período pós-operatório. Os dois grupos foram comparáveis quanto a idade (65 ± 10 anos vs. 65 ± 9 anos), classificações CCS e NYHA. RESULTADOS: O número médio de enxertos com CEC foi de 3,10 vs. 2,26 sem CE. Infarto peri-operatório, assim como morbidade e mortalidade (7/181 vs. 6/122) foram comparáveis. Apesar de mais elevados no grupo com CEC, os níveis pós-operatórios de CK-MB e troponina T não atingiram diferença estatística, tendo sido observados 21 infartos agudos por critérios bioquímicos que se distribuíram igualmente entre os grupos. Uma correlação inversa entre o número de enxertos e a liberação de troponina foi observada na fase inicial da nossa experiência sem CEC. Não houve relação entre a localização do enxerto e a incidência de infarto ou liberação de troponina. CONCLUSÃO: A proteção miocárdica, morbidade e mortalidade obtidas com as duas técnicas de revascularização estudadas foram semelhantes. Considerando os efeitos adversos da CEC, já documentados na literatura, particularmente sobre os sistemas neurológico, respiratório e renal sugerimos esta técnica como uma alternativa segura para a revascularização miocárdica.

Modifications of airway reconstruction in children.

We review our treatment experience of subglottic stenosis in 66 children. Sixty-one of these children required some form of airway expansion using cartilage grafts. Eight children had grade I (Cotton classification), 15 grade II, 28 grade III, and 15 grade IV stenosis. All patients with grade I and II lesions were decannulated. Ninety-three percent of grade III patients and 67% of grade IV patients were also ultimately decannulated. Laryngotracheal reconstruction with costal cartilage grafting has become widely accepted for treatment of severe laryngotracheal stenosis. Several modifications of this technique have been employed to treat our patients. Recently, we have used a modified single-stage technique with an endotracheal tube stent, externally secured for 1 week, to avoid postoperative intensive care unit admission for sedation and/or paralysis, and its related complications. Posterior graft design and placement without sutures was also performed in 20 cases. A two-surgeon technique that involves a simultaneous endoscopic control of incision of the stenotic area was employed. These modifications will be described in detail.

Eyelid reconstruction with tarsomarginal transplant

In the past 3 years, 85 basal cell carcinomas were treated in our clinic using eyelid reconstruction. During the same period, 54 lids were reconstructed after other diseases, mostly after chemical burns. In one of the 54 patients, the upper lid was reconstructed using a tarso-marginal graft after congenital coloboma. In 31 of the 85 patients with basal-well carcinoma (36%), so much tarsus was lost that a transplantation of tarsus was necessary. Fifteen of the 31 patients were treated with a Hughes-plasty and 16 using a tarsomarginal graft, two in the upper lid. In eight of the remaining 16 cases, the defect was less than one half of length, so that the graft was taken from the second lower lid. In the remaining eight patients, the defect was two thirds of length or longer. In six cases, a 7 mm-graft was taken from the upper lid. As the tarsus from the upper lid measures 10 mm and is thus twice as big as the lower lid tarsus, it was divided into two grafts, resulting in two grafts measuring 7 x 5 mm. They were placed in the lower lid ("double tarsomarginal graft"). The former lower part with lashes was placed in the middle of the lower lid, the former upper part peripherally. In two patients, the defect was healed with three tarsomarginal grafts. A pedicle skin flap was transposed to cover the posterior grafts. Remaining defects were closed with free skin transplants. The tarsomarginal graft permits a short operation time and early rehabilitation of the patients. The disadvantage of the double tarsomarginal graft is that the more valuable upper lid tarsus is used to reconstruct the less valuable lower lid tarsus.

The Influence of Bony Architecture on Fixed Membranous Bone Graft Survival

The aim of this study was to examine the influence of membranous bone graft architecture on graft survival. Eighteen adult New Zealand rabbits underwent full-thickness harvesting of their zygoma, which was then divided into two parts, resulting in a wider, thicker anterior graft and a tapered posterior graft. The grafts were then rigidly fixed, one to each nasal bone, using titanium lag screws. On postgrafting days 15 and 45, 3 animals each were killed. The remaining 12 animals were killed on day 90. The graft, graft-host interface, and contralateral zygoma were assessed volumetrically, histologically (nondecalcified), and stereologically. Volumetrically, the anterior (thicker, wider) grafts demonstrated 100% survival while the posterior (thinner, more narrow) grafts demonstrated 80% survival (p = 0.004). Histologically, the anterior grafts demonstrated less resorption and porosity and greater labeling activity. At the graft-host interface, the anterior grafts exhibited a 2.5-fold increase in full incorporation of the grafts, and the posterior grafts had almost twice the incidence of nonincorporation. Stereological measurements, including interlabel width (20.3 microns anteriorly, 18.9 microns posteriorly), confirmed the enhanced survival of the anterior grafts. Using multiple forms of analyses, this study demonstrates that membranous bone graft architecture influences graft survival. To assist in understanding these differences, we also analyzed the normal contralateral zygoma. While the anterior and posterior halves had a relatively constant amount of bicortical bone, the thicker grafts had a proportionally greater trabecular component (i.e., increased diploë-to-cortical ratio). In the rabbit model, differences in membranous bone thickness imply differences in the cancellous portion of the graft, thereby influencing ultimate graft survival.

Complex abdominal and thoracoabdominal aortic aneurysm reconstruction

Complex reconstructions of the abdominal aorta are required for aneurysms that require visceral or splanchnic revascularization, when the aorta is inflammatory or infected, when a fistula to the vena cava or bowel is present, and when the aneurysm involves the juxtarenal, pararenal segments, or the full length of the abdominal aorta. The technique for full-length abdominal and thoracoabdominal aortic reconstructions has been modified to separate the visceral and spinal cord revascularization from the body of the main graft. The visceral, renal, and intercostal arteries are not directly reimplanted into the aortic graft but rather into sidearm grafts using a patch inclusion technique. The reconstruction commences distally by anastomosing the main graft to the aortic bifurcation or to the iliac arteries as appropriate. The main graft is then anastomosed to the proximal aorta after which the aortic clamps are released to perfuse the lower limbs. The intercostal arteries are reimplanted into a posterior sidearm graft followed by visceral and renal artery reimplantation into an anterior sidearm graft. This technique reimplantation into an anterior sidearm graft. This technique reduces the period of left ventricular strain to the time taken to complete the upper aortic anastomosis. It also allows separate control of the visceral and intercostal implantations should bleeding occur, without the necessity to reclamp the main body of the graft.

Experience with one-stage laryngotracheal reconstruction

Eight patients (ages 10 months to 5 years) underwent laryngotracheal reconstruction (LTR) without intraluminal stenting or tracheostomy. All patients had moderate to severe acquired or congenital subglottic stenosis. Six patients were tracheostomy-dependent prior to reconstruction. The other two children were intubated and would have required tracheostomy for airway control. LTR and decannulation/extubation were accomplished as a one-stage procedure. Autologous rib cartilage was used (anterior graft only — 6 patients, anterior and posterior graft — 3 patients) and patients were intubated for 7–10 days. Pulmonary complications from the week-long intubation and intensive care unit stay were common, but easily managed. Seven of eight patients were successfully decannulated/extubated.