Class II antigenicity of human cartilage: relevance to the use of homologous cartilage graft for reconstructive surgery

The presence and distribution of class II transplantation antigens was studied on fresh and Merthiolate-preserved human nasal, tracheal, auricular, and rib cartilage using monoclonal antibodies in an indirect immunoperoxidase method. Substantial class II antigen expression was found on cells of the superficial area of the perichondrium of the nasal, auricle, and tracheal cartilages. In contrast, cartilage tissue lacked cells with detectable class II antigens. Our results indicate that the host response to fresh cartilage graft is induced by class II antigens presented in the perichondrium. A complete disappearance of this class II antigenicity of perichondrium can be achieved by means of an adequate Merthiolate preservation.     

The role of graft material in aortic reconstructive surgery.

Graft replacement of an aneurysmal abdominal aorta and bypass grafting for aorto-iliac occlusive disease has proven effective since synthetic materials were introduced three decades ago. During the period 1978-1981, 584 patients underwent aortic reconstruction for aneurysmal or aorto-iliac occlusive disease. Two hundred fifty-four patients (43%) were operated for aneurysms while 330 (57%) patients had symptomatic aorto-iliac occlusive diseases. There were 508 (87%) men and 76 (13%) women. Associated disease was common, with 245 patients (42%) having arteriosclerotic heart disease, 291 (50%) hypertensive, 128 (22%) having manifestations of extracranial occlusive disease, and 50 (8.6%) having diabetes mellitus. Sixty-four (10%) patients in this series had coronary revascularization prior to their aortic graft. One hundred five (17.9%) carotid endarterectomies had been performed previously or immediately prior to aortic grafting. Distal reconstructive operations had been performed in 106 patients (18%). Renal or mesenteric revascularizations were performed concomitantly in 87 and eight patients, respectively. One hundred two femoral reconstructions or distal bypasses were also performed to assure adequate outflow. Thirteen (2.27%) deaths occurred during the first 30 days. Cardiac problems accounted for eight of these deaths. Graft occlusion occurred in the immediate postoperative period in four (0.4%) limbs. During the follow-up, an additional seven limbs (1.04%) have occluded. There have been no other complications associated with the grafts during the follow-up period. Results in this series affirm the authors' strong commitment to direct aortic reconstruction.     

The arterial anatomy of the eyelid: importance for reconstructive and aesthetic surgery.

PURPOSE: The aim of the study was to investigate the arterial distribution of the eyelids. METHODS: The location, course, length and diameter of eyelid arteries were determined in 19 preserved and latex injected adult male cadaver heads. RESULTS: The diameter of the medial palpebral artery was found to be 1.50+/-0.28mm on the right, and 0.70+/-0.12mm on the left. The diameter of the lateral palpebral artery was measured as 0.62+/-0.10mm on the right, and 0.59+/-0.12mm on the left. The medial palpebral arteries travelling in the medial part of the eyelids usually arose as separate branches for the upper and lower lids, as superior and inferior medial palpebrals. In all cases, four arterial arcades, the marginal, peripheral, superficial orbital, and the deep orbital arcades, were revealed in the upper palpebra. These arterial arcades gave off small perforating branches. The perforating branches were identified on both sides of the tarsal plate and the orbicularis muscle. In four cases (11%) visible arterial variation was found near the inferolateral end of the levator palpebrae. Although many differences in the arterial features of the eyelid have been noted, there may not be a significant difference in the basic vasculature of the palpebra among races. A better understanding of the palpebral vascularity should allow modification of reconstructive techniques and reduce postoperative complications after eyelid surgery.     

Precision carving of costal cartilage graft for contour fill in aesthetic and reconstructive rhinoplasty

Background:

Autogenous costal cartilage is a good option for large volume requirements in rhinoplasty, when septal or conchal cartilages do not suffice. Reluctance to use costal cartilage is due to apprehension of warping. However, warping can be avoided if we follow the principle of balanced section as advocated by Gibson and Davis. “Warping” can also be utilized to change the curvature of the graft.

Materials and Methods:

We have used 69 costal cartilage grafts as a solid piece for contour fill in rhinoplasty in 31 patients over the last 10 years. Principle of balanced section as advocated by Gibson and Davis was adhered to while carving the grafts, however some grafts were allowed to warp to get different sizes and shapes.

Results:

All the procedures were uneventful. Aesthetic appearance of all patients was satisfactory and acceptable to all the patients. In two cases, the dorsal graft minimally shifted to one side, but remained straight. In one patient, there was late appearance of distortion.

Conclusion:

The mode of cartilage warping is predictable and it can be used to advantage. Apprehension to use costal cartilage graft is unjustified, as with precision carving a desired shape can be obtained.KEY WORDS: Autogenous cartilage, balanced section, costal cartilage graft, rhinoplasty, warping     

Use of bone graft substitutes in lower extremity reconstructive surgery

Autologous iliac crest graft has been a standard source of supplementary bone for treating bony defects, fractures and arthrodeses. Bone graft substitutes have recently become widely available. This paper reports on the use of bone graft substitute in 28 patients that otherwise would have required an iliac crest graft. Twenty-four of the 28 operations were successful in the primary procedure with four patients requiring a second procedure that was then successful.     

Rehabilitation of the paralysed or lax lower eyelid using a graft of conchal cartilage.

Excessive laxity of the tarso-ligamentous sling of the lower eyelid may be caused by inadequate muscular support (resulting from injury to the muscle, facial palsy or senile degeneration) or prolonged mechanical distension (exophthalmia). Numerous techniques have been devised for functional reconstruction of the distended lower eyelid, based upon the principle that restoring the lower eyelid to its anatomical position will improve lacrimal transit andre-establish its natural protective function. We now use an autologous conchal cartilage graft to treat the distended or atonic lower eyelid. We review our results in a retrospective study of 20 patients, and aim to identify the indications for this procedure and to evaluate its advantages and disadvantages relative to other existing methods. All of our patients reported functional improvement after the operation in terms of decreased dry-eye symptoms, less epiphora and a decline in keratitis and conjunctivitis. All patients also reported a visible cosmetic improvement postoperatively. The major drawback of this operation is the partial loss of the visual field when looking down, due to the limited lowering of the lower eyelid. The stability of our results compares favourably with that achieved using other currently available techniques. We conclude that autologous conchal cartilage grafting is an effective procedure for improving both the function and the appearance of the atonic lower eyelid.     

Free flaps in reconstructive surgery.

Advances in technique, training and instrumentation have improved the patency rates for small vessel anastomosis. This, together with the introduction of more reliable donor sites for free tissue transfer, have resulted in success rates in excess of 90%. The technique is not associated with an increase in mortality or morbidity; on the contrary there is the advantage of primary reconstruction with a wide choice of donor sites offering the correct amount and type of tissue required. Single-stage, effective reconstruction, aimed at primary wound healing remains the aim of the reconstructive surgeon and free tissue transfer offers the most versatile and reliable method currently available.     

Cosmetic eyelid surgery and the problem eyelid.

The human eyelid is an amazingly complex structure that is responsible for protecting, moisturizing, and reconstituting the external surface of the eye. Compromise of any of the tarsoligamentous supporting structures of the eyelids can result in eyelid malposition, corneal compromise, and even blindness. Failure to recognize these abnormalities in patients seeking cosmetic eyelid surgery can lead to disastrous results. The most common structural eyelid abnormalities encountered in patients seeking cosmetic eyelid surgery and prophylactic and reconstructive surgical techniques to deal with these difficult problems are discussed.     

Anaesthesia for reconstructive surgery

Skin or tissue defects that cannot be closed primarily with simple suturing may need skin grafts, tissue expanders or flaps to maintain skin integrity and prevent infection. Flaps may be local, pedicled or free and may involve skin, muscle, bone, bowel or a combination. Local and pedicled flaps keep their primary vascular supply while free flaps have their circulation detached and reanastomosed distantly. Free flaps are therefore particularly vulnerable to ischaemia. Primary ischaemia occurs during the clamping of the vascular supply until anastomosis is completed and reperfusion achieved. Secondary ischaemia refers to any subsequent hypoperfusion and can be prevented by good anaesthetic technique and active fluid therapy. The guiding principle of anaesthesia for free flap surgery is the maintenance of optimum blood flow as summarized by the Hagen-Poiseuille equation. Thus, the goals of anaesthesia for free flap surgery are vasodilatation, good perfusion pressure and low viscosity. Balanced general anaesthesia, good analgesia and normothermia provide vasodilatation. Optimal perfusion pressure and low blood viscosity is achieved by modest hypervolaemic haemodilution guided by the CVP and haematocrit. In addition to basic monitoring, these patients require invasive blood pressure monitoring, CVP, temperature and urine output measurement. Active warming is started before induction of anaesthesia and continued into the post-operative period. A regional anaesthetic technique is preferred to cover the free flap recipient site. Careful positioning of the patient and prophylaxis against deep venous thrombosis is imperative for such a long operation.     

Anaesthesia for reconstructive surgery

Reconstructive surgery is aimed at the restoration of shape and function following tissue loss due to trauma, oncological surgery, burns and infection. Techniques range from simple primary wound closure at the bottom to complex microvascular free tissue transfer at the top rung of the reconstructive ladder.Free flap surgery involves separation of the flap from its original vascular supply and microvascular reanastomosis at a distant site and is associated with substantial transient ischaemia of the transferred tissue. Anaesthetic management plays an important role in successful free flap surgery.All factors promoting vasoconstriction need to be eliminated in order to facilitate blood flow through the transferred tissue.In this respect, maintenance of an adequate arterial blood pressure, normothermia and normocarbia, institution of moderate hypervolaemic haemodilution and effective pain management are the main principles.In spite of studies describing the effects of particular drugs on the microcirculation no single ideal anaesthetic agent has yet been identified for this type of surgery.Free flap failure occurs mainly during the first 48 hours postoperatively with venous thrombosis being more common than arterial occlusion. Prompt surgical revision is the mainstay of flap salvage. The overall success rate of microvascular free tissue transfer in high volume centres exceeds 90%.     

Technique for experimental surgery: Simple cautery for experimental microvascular surgery

A simple and safe method of themocoagulation of small vessels, particularly useful in an experimental microsurgical laboratory, is described. This thermocautery can be readily prepared, and the vessels can be cauterized as close as 0.5 mm from the origin.     

Is hysterectomy or the use of graft necessary for the reconstructive surgery for uterine prolapse?

The aim of this study was to evaluate whether hysterectomy or the use of graft is necessary for the reconstructive surgery for uterine prolapse. One hundred sixty-eight patients were categorized into the 3 groups: group I, abdominosacral colpopexy with mesh and hysterectomy (n = 63); group II, abdominosacral uteropexy with mesh (n = 35); group III, abdominal uterosacrocardinal colpopexy and hysterectomy (n = 70). Perioperative and postoperative complications, functional outcomes, and anatomical recurrences were assessed. The median follow-up was 36 months in all surgery groups. In the complication rates and functional outcomes, no difference was noted, except for operation time (longer in group I, p = 0.001) and hemoglobin loss (greater in group II, p = 0.002). There was a significant difference in the cumulative anatomical cure rates (p < 0.0001). The risk of recurrence in group III was 6.2 times higher than in group I. In conclusion, the use of graft, rather than hysterectomy, might be necessary for the reconstructive surgery for uterine prolapse.     

Precultivation of engineered human nasal cartilage enhances the mechanical properties relevant for use in facial reconstructive surgery

OBJECTIVE: To investigate if precultivation of human engineered nasal cartilage grafts of clinically relevant size would increase the suture retention strength at implantation and the tensile and bending stiffness 2 weeks after implantation. SUMMARY BACKGROUND INFORMATION: To be used for reconstruction of nasal cartilage defects, engineered grafts need to be reliably sutured at implantation and resist to bending/tension forces about 2 weeks after surgery, when fixation is typically removed. METHODS: Nasal septum chondrocytes from 4 donors were expanded for 2 passages and statically loaded on 15 x 5 x 2-mm size nonwoven meshes of esterified hyaluronan (Hyaff-11). Constructs were implanted for 2 weeks in nude mice between muscle fascia and subcutaneous tissue either directly after cell seeding or after 2 or 4 weeks of preculture in chondrogenic medium. Engineered tissues and native nasal cartilage were assessed histologically, biochemically, and biomechanically. RESULTS: Engineered constructs reproducibly developed with culture time into cartilaginous tissues with increasing content of glycosaminoglycans and collagen type II. Suture retention strength was significantly higher (3.6 +/- 2.2-fold) in 2-week precultured constructs than in freshly seeded meshes. Following in vivo implantation, tissues further developed and maintained the original scaffold size and shape. The bending stiffness was significantly higher (1.8 +/- 0.8-fold) if constructs were precultured for 2 weeks than if they were directly implanted, whereas tensile stiffness was close to native cartilage in all groups. CONCLUSION: In our experimental setup, preculture for 2 weeks was necessary to engineer nasal cartilage grafts with enhanced mechanical properties relevant for clinical use in facial reconstructive surgery.