The submuscular aponeurotic system (SMAS): a histologic and comparative anatomy evaluation.

The submuscular aponeurotic system (SMAS) has been steeped in controversy. The goal of our anatomic study was to further clarify the existence of the SMAS. With an operating microscope, we performed dissections in 10 fresh cadaver heads (20 hemiheads) exposing the SMAS through a face lift incision. Through the operating microscope we were able to identify the SMAS and its relationship to other anatomic structures. Full-thickness longitudinal sections were obtained for routine histologic studies along various surgically relevant regions of the SMAS. In addition, dissections were accomplished with the operating microscope on 12 rhesus monkey fetuses ranging in age from a few weeks to 8 months. Data obtained from the fresh cadaver microdissections, topographic histology, and comparative anatomy revealed the presence of the SMAS as a distinct fibromuscular layer composed of the platysma muscle, parotid fascia, and fibromuscular layer covering the cheek.

Rigid internal fixation with miniplates and screws: a cost-effective technique for treating mandible fractures?

Traditional methods of fixation for stabilization of mandible fractures primarily center around intermaxillary fixation with or without open reduction. During the past decade, rigid internal fixation with miniplates and screws has attained widespread acceptance in the management of acute traumatic injuries to the mandible. With continuing emphasis on cost containment in health care delivery, plastic surgeons will be expected to justify their therapeutic methods as beneficial as well as cost-effective. This is particularly important when a number of acceptable procedures are readily available. The purpose of our investigation was retrospectively to compare treatment with intermaxillary fixation alone, interosseous wire osteosynthesis, and rigid internal fixation with miniplates and screws. We analyzed the hospital records of three such treatment groups, each consisting of 25 patients. Despite initial purchase costs, increased operating time, and the need to develop the skills required to apply the hardware, our study clearly demonstrated that miniplates and screws remain a cost-effective approach to caring for fractures of the mandible. Associated advantages include a quicker return to a preinjury life-style, decreased weight loss, improved oral hygiene and wound care, and protection of the airway, thereby eliminating monitored intensive care unit admissions.

Use of maxillary miniplates and screw system in the treatment of hand fractures: a preliminary report.

The vast majority of hand fractures can be adequately treated with techniques such as closed reduction and external splinting or with a variety of internal fixation devices. Choice of stabilization methods depends on individual surgical preference, fracture location, and the geometry of the bony injury. Fracture stabilization that allows early mobilization is advantageous in achieving rapid bone healing and restoration of function by minimizing joint and tendon complications. Rigid internal fixation with miniplates and screws permits stabilization and compression of fracture segments, thereby permitting early bone loading and motion. Although the role of rigid internal fixation with miniplates and screws in hand fractures is well documented in the literature, in this article we present our preliminary experience with Howmedica's (Rutherford, NJ) Luhr vitallium miniplate and screw system in treating hand injuries.

A possible serum marker for rejection after small intestine transplantation.

Frequent histologic evaluation of mucosal biopsies remains the most reliable method of monitoring and diagnosing rejection after small intestine transplantation, but lengthy processing time can result in delay in diagnosis. Unfortunately, a serum marker for monitoring small intestine transplantation rejection has not been identified. Hexosaminidase, a lysosomal acid hydrolase, has been shown to increase in serum in association with intestinal ischemia, a finding also associated with acute rejection after small intestine transplantation. We measured N-acetyl hexosaminidase levels after transplantation in three groups of five rats each as follows: Group I, Lewis strain small intestine to Lewis recipients; Group II, Wistar small intestine to Lewis recipients; and Group III, Wistar small intestine to Lewis recipients treated with 25 mg/kg per day of cyclosporine. Serum N-acetyl hexosaminidase levels and mucosal biopsies were obtained on days 0, 2, 4, 6, 8, 10, 12, 14, and 21. Rats in Groups I and III survived without gross evidence of rejection. Three rats in Group II died between 8 and 10 days, and serum N-acetyl hexosaminidase levels increased 24 to 48 hours before death. In the remaining Group II rats, the N-acetyl hexosaminidase levels were significantly higher on days 10, 12, and 14 after transplantation (p less than 0.05). In two of five rats, the histologic changes of rejection occurred later than the increase in N-acetyl hexosaminidase levels. Because measurement of N-acetyl hexosaminidase levels is a rapid and simple serum assay, it may be useful for monitoring rejection after small intestine transplantation.

Morphologic significance of bifid uvula.

Bifid uvula is often regarded as a marker for submucous cleft palate although this relationship has not been fully confirmed. The reason for the tacitly assumed connection between these two anomalies has, in part, been perpetuated by the generally accepted definition of submucous cleft palate as the triad of bifid uvula, notching of the hard palate, and muscular diastasis of the soft palate. Recently, investigations have provided evidence of more subtle manifestations of submucous cleft palate by the use of nasopharyngoscopic examination of the palate and pharynx. It has been determined that submucous cleft palate can occur even when a peroral examination shows an intact uvula. This finding places the "marker" relationship in question. In order to determine the frequency of association between bifid uvula and submucous clefting, a total ascertainment of children with bifid uvula from a suburban pediatric practice was examined nasopharyngoscopically. It was determined that in all but two cases, children with bifid uvula had some or all of the landmarks of submucous cleft palate. Several of the children were found to have velopharyngeal insufficiency and mildly hypernasal speech. This finding prompts caution in the recommendation of adenoidectomy in the presence of bifid uvula.

Sling operation for recurrent stress incontinence using the tendon of the palmaris longus.

A sling procedure is described for recurrent stress incontinence in women who had been previously treated, unsuccessfully, by one or more surgical interventions. The procedure consists of combining a vaginal Kelly urethral plication with a sling prosthesis, using the tendon of the palmaris longus. The former will correct the bladder neck funneling while the latter will restore its position to a high retropubic point, in a hammock suspended from Cooper's ligament. The palmaris longus is one of the superficial groups of flexors. Its advantages are in the tendon's availability, its location for accessibility, its relative ease of removal, and the fact that it is functionally nonessential. Six patients have been treated with this technique with excellent results after one to three years of follow-up.

Post-traumatic facial nerve paralysis: three cases of delayed temporal bone exploration with recovery.

No consensus exists today on the management of immediate-onset post-traumatic facial nerve paralysis. Controversy surrounds the timing of surgical intervention and the role of electrophysiologic testing. Three patients are presented who sustained immediate, complete facial paralysis following closed head trauma. They did not have prompt facial nerve decompression. In each case, electroneurography and electromyography showed complete nerve degeneration and denervated muscle. Despite the results of the electrophysiologic tests, all patients underwent late surgical decompression of the nerve: one at 2 1/2 months, one at 3 months, and one as late as 14 months after injury. They all had good recovery of facial function within 6 months of surgery. Early surgical intervention has been advocated in post-traumatic facial nerve paralysis if any benefit is to be gained. It is thought that late surgical intervention is unlikely to yield further improvement in the facial nerve function. Experience with these cases suggests that surgical exploration of the facial nerve is indicated at anytime, as it may be beneficial even in very old injuries. The prognostic value of electroneurography and electromyography in determining facial nerve recovery and in deciding upon facial nerve surgery is questioned.

The role of lateral pharyngeal wall movement in pharyngeal flap surgery.

A total of 202 patients with pharyngeal flaps were assessed with nasopharyngoscopy and multiview fluoroscopy to determine the role of lateral pharyngeal wall movement postoperatively. Variations in the construction of flaps resulted in three categories: namely, a long narrow flap with a high insertion, a short broad flap with a low insertion, and an intermediate-size flap that is inserted in a position somewhere between the first two. It was found that in all cases where there was no evidence of velopharyngeal insufficiency, the sole determiner of velopharyngeal closure was the medical excursion of the lateral pharyngeal walls to the sides of the flap. In flap failures, the causes for velopharyngeal insufficiency were inappropriate degree, level, and symmetry of the lateral pharyngeal wall motion. The success of pharyngeal flap surgery depends largely on the preoperative assessment of the velopharyngeal mechanism and the choice of a type of pharyngeal flap that will best assist closure of the velopharyngeal port during speech.

Neovascularization of skin flaps: route and timing.

Axial flaps were elevated in a pig and rat model. Selective ligation of the vascular pedicles on days 1 to 7 following elevation of the flap demonstrated total necrosis of all flaps when the pedicles were ligated on the first, second, and third postoperative day in the pig, and up to 6 days inthe rat. Pedicle ligation beyond this time did not produce flap necorsis, indicating the establishment of adequate neovascularization for flap survival. Selective ligation of the artery or vein did not appear to be significant in the pig. In the rat flap, however, survival tended to occur sooner. Adequate neovascularization for flap survival was demonstrated as arising from both the wound edges and the bed, although vascular channels occurring from the bed appeared to be of greater importance. The relatively rapid rate of neovascularization that occurs for adequate flap survival suggests that if some way could be found to maintain flap viability during the first week, the feeding vessels need no longer remain patent and may be ligated or used for other purposes. This interesting observation has already allowed very early successful defatting of clinically transferred flaps.

A comprehensive study of pharyngeal flap surgery: tailor made flaps.

Three methods of pharyngeal flap surgery were analyzed with multiview videofluoroscopy and nasopharyngoscopy at least six months post-operatively. It was found that, by varying the type of insertion of the flap into the palate, post-operative flap width could be "tailored" to the size of the gap in the velopharyngeal sphincter. The value of varying flap width according to gap size was assessed by analyzing speech results in 60 patients specifically assigned for narrow, moderate, or wide flaps. Results show a marked improvement in the effectiveness of pharyngeal flap surgery when operations are prescribed according to the degree of lateral pharyngeal wall motion seen pre-operatively.

Hepatic conversion of bilirubin monoglucuronide to diglucuronide in uridine diphosphate-glucuronyl transferase-deficient man and rat by bilirubin glucuronoside glucuronosyltransferase.

The microsomal enzyme uridine diphosphate (UDP) glucuronate glucuronyltransferase (E.C. 2.4.1.17) catalyzes formation of bilirubin mono-glucuronide from bilirubin and UDPglucuronic acid. Bilirubin glucuronoside glucuronosyltransferase (E.C. 2.4.1.95), an enzyme concentrated in plasma membrane-enriched fractions of rat liver, converts bilirubin monoglucuronide to bilirubin diglucuronide. Bilirubin glucuronoside glucuronosyltransferase activity was studied in homogenates of liver biopsy specimens obtained from patients with the Crigler-Najjar syndrome (Type I) and in subcellular liver fractions of rats homozygous for UDP glucuronate glucuronyltransferase deficiency (Gunn strain). In patients with the Crigler-Najjar syndrome (Type I) and in Gunn rats, hepatic UDPglucuronate glucuronyltransferase activity was not measurable; however, bilirubin glucuronoside glucuronosyltransferase activity was similar to that in normal controls. The subcellular distribution of bilirubin glucuronoside glucuronosyltransferase activity in Gunn rat liver was similar to the distribution observed in normal Wistar rat liver.When bilirubin monoglucuronide was infused intravenously into Gunn rats, 29+/-5% of the conjugated bilirubin excreted in bile was bilirubin diglucuronide. After transplantation of normal Wistar rat kidney, which contained UDPglucuronate glucuronyltransferase activity, in Gunn rats, the serum bilirubin concentration decreased by 80% in 4 days. The major route of bilirubin removal was biliary excretion of conjugated bilirubin, approximately 70% of which was bilirubin diglucuronide. Although patients with the Crigler-Najjar syndrome (Type I) and Gunn rats lack UDP glucuronate glucuronyltransferase, their livers enzymatically convert bilirubin monoglucuronide to diglucuronide in vitro. Conversion in bilirubin monoglucuronide to diglucuronide was demonstrated in Gunn rats in vivo.