Biomedical subjects

Matthew R Kaufman

Publications and source records attributed to Matthew R Kaufman.

5 recordsLinked to original sources

PubMed2005

The reverse radial forearm flap for soft tissue reconstruction of the wrist and hand.

Soft tissue defects of the upper extremity must be carefully assessed to determine the most appropriate method of coverage. Direct closure and local flaps represent the most basic techniques on the reconstructive ladder; however, they are inadequate for large or complex defects. Split thickness skin grafts are appropriate for granulating wounds with a bed of vascularized tissue; however, if there is an exposed joint or bone devoid of periosteum or tendon devoid of paratenon, there will be insufficient neovascularization, and the graft will inevitably fail. The reconstructive hand surgeon must then pursue more complicated techniques for wound coverage based upon knowledge of the available pedicled and free flaps. The reverse radial forearm flap potentially offers thin, mobile skin with similar characteristics to the skin over the dorsum of the hand. This flap is more versatile than the groin flap and probably more reliable than the posterior interosseous artery flap for coverage of moderate-sized defects of the dorsal or palmar wrist and hand and is specifically indicated for coverage of degloving injuries of the dorsal wrist and hand, after release of thumb-index finger web space, and for coverage of amputations of the thumb in preparation for toe-to-thumb transfer.

Contraindications↗

PubMed2003

Engineering cartilage growth and development.

The invocation of the principles of tissue engineering for the production of cartilage has been clearly defined. Investigators have delineated the protocols for cell harvesting, matrix configuration, and in vivo implantation, resulting in morphologically and histologically mature cartilaginous tissue. Tremendous advances in the science of materials science have increased the availability of synthetic, biocompatible, biodegradable polymers for creation of cell-polymer constructs. It has been well demonstrated that chondrogenesis is possible in nude animal models, through subcutaneous implantation or injectable methods. Assessment of neocartilage weeks to months after development has confirmed that it conforms to predetermined shapes and possesses the biomechanical properties of the tissue from which it is derived. Future studies must address the potential for inflammatory responses in immunocompetent hosts. Long-term biomechanical assessments of tissue engineered cartilage are needed to provide evidence of longevity for application in clinical settings. Although the regeneration of articular, hyaline cartilage has been well demonstrated, further investigation should assess tissue engineering of elastic cartilage, especially for use in facial reconstructive surgery. As refinement of tissue engineered cartilage continues, we approach the era of dramatic advances in facial reconstruction using this potential ideal substance.

Biocompatible Materials↗

PubMed2003

Treatment outcomes in the management of inverted papilloma: an analysis of 160 cases.

OBJECTIVE: The objective of this study is to compare the surgical options for treatment of inverted papilloma to determine the appropriate indications for conservative and aggressive management. STUDY DESIGN AND SETTING: A retrospective review of 160 patients with a diagnosis of inverted papilloma treated by the two senior authors (w.l. and h.f.b.) between 1973 and 2001. RESULTS: The study group consisted of 124 male and 36 female patients with an average age of 56 years. The follow-up period ranged from 10 months to 16 years (mean, 5.2 years). Seventy-eight patients (49%) had undergone prior surgery. Lateral rhinotomy was performed in 112 patients (70%), with a recurrence rate of 18%. Conservative removal was performed in 41 patients (26%), including 30 (19%) endoscopic approaches, with a recurrence rate of 12%. The remaining patients underwent midfacial degloving, osteoplastic approach, or craniofacial resection. The rate of malignant transformation was 7%. CONCLUSION: We present the largest personal series of cases of inverted papilloma to date. Our data suggest that conservative approaches, especially endoscopic removal, can be performed on selected lesions with recurrence rates that are comparable to those of more aggressive techniques. Those inverted papillomas that recur after treatment may represent a subset of lesions with an inherent aggressiveness, for which optimal treatment has yet to be determined.

Adolescent↗

PubMed2002

Sinonasal papillomas: clinicopathologic review of 40 patients with inverted and oncocytic schneiderian papillomas.

OBJECTIVE: To evaluate the pathological features and variations of sinonasal inverted and oncocytic papillomas and correlate the microscopic findings with the clinical behavior. STUDY DESIGN: A retrospective review and pathological assessment. METHODS: A retrospective review and pathological assessment were performed on 40 patients with a diagnosis of inverted papilloma treated by the senior author (w.l.) between 1994 and 2001. RESULTS: Forty cases were identified and reviewed. Seven patients developed recurrences (18%), and four underwent malignant transformations (10%). Pathological assessment revealed 34 (85%) inverted papillomas and 6 (15%) oncocytic schneiderian papillomas. Dysplasia was present in 26 cases (65%), including 9 cases (22%) of high-grade dysplasia (moderate to severe). Metaplasia of the sinonasal mucosa adjacent to inverted papillomas and oncocytic schneiderian papillomas was seen in 18 (45%) cases. Recurrence developed in two patients with oncocytic schneiderian papillomas (33%) and five patients with inverted papillomas (15%). Four cases (10%) of carcinoma ex papilloma were seen; one arose from oncocytic schneiderian papilloma (17%), and three arose from inverted papilloma (9%). Oncocytic schneiderian papilloma was more often mixed with typical inverted papilloma, rather than presenting in its pure form. CONCLUSIONS: Although oncocytic schneiderian papilloma is uncommon relative to inverted papilloma, the results suggest that they have higher rates of both recurrence and malignant transformation. The common admixture of oncocytic schneiderian papilloma with inverted papilloma speaks for a common etiological factor of these two lesions. A larger number of cases for analysis would be necessary to confirm the trend noted in our data. Nonetheless, pathological findings consistent with oncocytic schneiderian papilloma should be explicit in any classification system and justify aggressive treatment and careful postoperative surveillance.

Adult↗

PubMedDate not supplied

Autologous cartilage grafts enhanced by a novel transplant medium using fibrin sealant and fibroblast growth factor.

OBJECTIVE: To introduce and assess a system for the delivery of fibroblast growth factor to autologous cartilage grafts using fibrin sealant and analyze whether this "enhancement" results in reduced rates of cartilage resorption and greater preservation of normal architectural features compared with "unenhanced" cartilage grafts. METHODS: Auricular cartilage segments measuring 1 cm(2) were harvested from 12 New Zealand white rabbits, morselized, and implanted into the subcutaneous dorsum of the upper back for 3 months. The conditions included (1) cartilage alone; (2) cartilage + fibrin sealant; (3/4) cartilage + acidic or basic fibroblast growth factor (aFGF or bFGF); and (5/6) cartilage + fibrin sealant + aFGF or bFGF. Subsequent to graft harvest, gross and microscopic assessments were performed to assess size, structural integrity, and architectural features, with comparisons performed between each of the conditions. RESULTS: The mean areas of the harvested cartilage grafts treated with fibrin sealant + aFGF or bFGF were 1.23 cm(2) and 1.19 cm(2), respectively, while the corresponding value for the untreated (ie, cartilage alone) specimens was 1.03 cm(2). The percentage of decrease in size was 45% for the untreated specimens and 0% for the specimens treated with fibrin sealant + aFGF or fibrin sealant + bFGF. Cartilage treated with fibrin sealant + bFGF had the greatest quantity of elastin fibers of the 6 conditions. Cartilage grafts treated with fibrin sealant alone demonstrated the most intense ground substance staining on a computerized measure of pixel intensity. CONCLUSIONS: Our findings demonstrated significant improvements in graft quality using fibroblast growth factor and fibrin sealant or even fibrin sealant alone. These findings may justify changes in how cartilage grafts are prepared and delivered for facial augmentation procedures to reduce graft resorption and maintain the structural integrity of the cartilage. Further trials will be performed to elucidate the optimal growth factor concentrations for maximum structural and architectural benefits.

Animals↗