Biomedical subjects
Publications and source records attributed to M Constantinides.
Rejuvenation of the midface is a challenge in facial plastic surgery. To this end, several techniques have been developed to address the changes seen in the midface with aging. Specifically, ptosis of the malar fat pad and deepening of the nasolabial fold contribute to the aesthetic changes that characterize midfacial aging. The history of modern facelifts and deep-plane facelift techniques to correct the nasolabial fold are presented.
BACKGROUND: Expanded polytetrafluoroethylene (ePTFE) is a synthetic porous material that has been used for static suspension in facial paralysis. It is manufactured in thin (1-mm or 2-mm) sheets that can be cut into strips and implanted through keyhole facial incisions. Regional deformities are addressed by multiple suspensions that provide cosmetic and functional therapy. The use of ePTFE eliminates donor site morbidity associated with the traditional harvest of fascia from either the temporal area or fascia lata. However, properties unique to this alloplast contribute to the complications that have occurred after its use in facial reanimation. OBJECTIVE: To describe complications with the use of ePTFE for facial suspension. SETTING: Academic medical center. METHOD: Retrospective chart review and review of literature. RESULTS: Six patients with facial paralysis who were treated with the ePTFE sling procedure had complications. Five slings failed because of stretch despite prestretching at implantation. One patient developed a late wound infection requiring removal of the sling. CONCLUSION: An ePTFE facial sling is an option for static facial suspension that can be therapeutic for patients with seventh nerve damage. There is a high rate of complications leading to revision surgery. Future studies are needed to evaluate alloplastic alternatives to ePTFE.
There is continuing controversy surrounding the most effective treatment of glottic carcinoma involving the anterior commissure (AC). Surgery has been the preferred method of treatment, since studies previously indicated early tumor invasion of the thyroid cartilage at the AC, thereby assuming less curability by radiotherapy (RT). Subsequent laryngeal anatomic studies and refinement of RT techniques have brought into question the ineffectiveness of curative irradiation. A retrospective review of 174 patients with early-stage glottic carcinoma treated with standard fractionation curative RT revealed 34 patients with T1 and T2 lesions involving the AC. Allowing for a follow-up of at least 3 years, we observed only a 12% (4 of 34 patients) local recurrence rate after RT alone, with excellent voice quality and no major complications related to the irradiation. The 4 local recurrences were controlled by total laryngectomy, although 2 patients developed distant metastatic disease. Radiotherapy represents an effective method of treating T1 squamous cell carcinoma of the glottis with AC involvement. The small number of T2 glottic carcinomas in this study prevents a meaningful conclusion concerning treatment of these lesions.
The deep nasolabial fold and other facial furrows and wrinkles have challenged the facial plastic surgeon. A variety of techniques have been used in the past to correct these troublesome defects. Advances in the last five years in new materials and design have created a subcutaneous implant that has excellent properties. This article reviews the development and use of Softform facial implant.
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Rabbit muscle phosphorylase phosphatase has been isolated in different laboratories as an inactive complex of Mr = 70,000, composed of separate catalytic (Mr = 38,000) and regulatory (Mr = 31,000) proteins. The regulatory protein is identical to one of two heatstable inhibitors called inhibitor-2 (I2). Antiserum raised in sheep against I2 by repeated immunization potently blocked inhibitory activity, whereas preimmune serum did not. Immunoglobulins which blocked inhibitory activity were purified by affinity chromatography with I2 as the immobilized ligand. Using a "Western" immunoblotting procedure, as little as 1-5 ng of pure I2, obtained by electroelution of the Mr = 31,000 band of I2 from a polyacrylamide gel segment, were detected. Immunoblotting of the immunogen revealed only a band at Mr = 31,000, indicating the absence of contaminating antigenic proteins. When extracts of skeletal muscle and other rabbit tissues were denatured directly in dodecyl sulfate for immunoblotting the most intensely stained band was present at Mr = 60,000, rather than at Mr = 31,000 as expected. A small amount of I2 and other bands were detected, in particular at Mr = 36,000 and 25,000. Subsequent to heat treatment of the tissue extracts, there was an enrichment of I2 content relative to the Mr = 60,000 band. The results indicate the existence of a Mr = 60,000 protein related to I2. Activation of phosphorylase phosphatase in a muscle extract by treatment with Co2+ plus trypsin exactly coincided with digestion of the Mr = 60,000 immunoreactive protein. Available data indicate that this protein may function as a regulatory subunit of phosphorylase phosphatase.
The molecule N-(2,6-dimethyl-phenyl-carbamoyl-methyl)-iminodiacetic acid (HIDA), capable of chelating reduced 99mTc, was synthesized, characterized, labeled with 99mTc, and studied in experimental animals. The results indicated that the new 99mTc-radiopharmaceutical is rapidly cleared from the blood to the liver, then rapidly removed to the gallbladder and excreted into the duodenum through the common bile duct. A comparative kinetic study of 99mTc-HIDA and 131I-Rose Bengal performed in rabbits demonstrated that both radiopharmaceuticals had a similar blood clearance rate, but cleared at a different rate from liver to gallbladder. 99mTc-HIDA showed a faster accumulation in the gallbladder than 131I-Rose Bengal. These findings, combined with the advantage of the low acute toxicity of HIDA, were promising enough to encourage a further evaluation and clinical investigation of this new Tc-99m hepatobiliary agent.
OBJECTIVE: To review the indications for, surgical techniques of, and results of vertical lobule division (VLD) of the alar cartilages. DESIGN: Prospective study of patients assigned to undergo variations of VLD of the lower lateral cartilages. SETTING: Private facial plastic surgery practice in a major university teaching hospital. PATIENTS: Twenty-four patients who underwent variations of VLD of the lower lateral cartilages with re-creation of an intact strip, including 4 patients undergoing revision. MAIN OUTCOME MEASURES: Postoperative photographs were reviewed for tip projection and rotation, tip symmetry, bossae, knuckles, columellar position and length, and alar retraction. Patients were polled about their overall satisfaction with nasal aesthetics and degree of subjective nasal obstruction preoperatively and postoperatively. RESULTS: Vertical lobule division decreased projection in 22 of 22 patients, increased rotation in 12 of 12 patients, decreased rotation in 1 of 2 patients, corrected tip asymmetry in 3 of 4 patients, and shortened a long infratip lobule in 1 patient. Postoperatively, bossae and knuckling developed in 1 patient, and 2 patients demonstrated alar retraction that did not exist preoperatively. One patient undergoing revision noted worsened nasal obstruction not related to VLD. CONCLUSIONS: Vertical lobule division is a reliable, safe technique with predictable outcomes in tip repositioning. It allows for preservation of a strong tip complex while adding versatility to tip refinement.
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