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Roland D Eavey

Publications and source records attributed to Roland D Eavey.

9 recordsLinked to original sources

Pediatric cholesteatoma: canal wall window alternative to canal wall down mastoidectomy.

OBJECTIVE: A previous pilot series described a hybrid mastoidectomy technique, canal wall window (CWW), which substituted for the canal wall down (CWD) procedure and involved slitting the posterior canal wall. The current, larger series compares the results of the CWW procedure with conventional surgical techniques. STUDY DESIGN: Retrospective analysis of 78 pediatric ears. SETTING: Academic tertiary referral center. PATIENTS: The mean patient age was 13.5 years. MAIN OUTCOME MEASURE(S): The data analyzed included ears later requiring conversion from CWW to CWD, dry/moist ear results, recidivation determined by two separate methods, and audiometric data statistically analyzed using independent-samples analysis (unpaired, two-tailed Student's t test). RESULTS: First, of 42 CWW ear procedures, 6 (14%) later required conversion to CWD. Second, dry ear results were as follows: for CWW, 94%; for CWD, 92%; and for CWU (canal wall up), 90%. Third, recidivation determined at 1 year (standard rate) was, for CWW, 19.5%; for CWD, 0%; and for CWU, 7.7%; the at-risk calculation rate was, for CWW, 27%; for CWD, 0%; and for CWU, 8.3%. The 6-year recidivation rate for all three surgical techniques was 0%. 4). The mean preoperative-to-postoperative four-tone air-bone gap change was, for CWW, from 29.7 to 26.4 dB; for CWD, from 32.9 to 39.0 dB; and for CWU, from 21.0 to 25.2 dB (postoperative CWW to CWD, p < 0.005). A postoperative air-bone gap result of 0 to 20 dB was achieved as follows: with CWW, in 13 of 36 ears; with CWD, in 2 of 14 ears; and with CWU, in 9 of 22 ears. CONCLUSION: Frequently, a CWW procedure can be substituted for a traditional CWD procedure. In the extended series, the CWW technique continued to provide hearing results similar to CWU rather than to CWD procedures in a young population who will bear the surgical outcome for many decades.

Adolescent↗

Sylvan Stool.

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History, 20th Century↗

Evaluation of noise-induced hearing loss in young people using a web-based survey technique.

OBJECTIVE: Many adolescents and young adults consciously expose themselves to loud music for entertainment. We hypothesized that these individuals might not be aware that exposure to loud music could result in hearing loss. Furthermore, we wished to assess the feasibility of a web-based survey to collect health information from this group. METHODS: A 28-question survey was designed to target adolescents and young adults. The survey contained questions about views toward general health issues, including hearing loss, and was presented to random visitors at the MTV web site. RESULTS: In 3 days, 9693 web surveys were completed. Hearing loss was defined on a Likert scale as "a very big problem" by 8% of respondents compared with other health issues: sexually transmitted diseases, 50%; alcohol/drug use, 47%; depression, 44%; smoking, 45%; nutrition and weight issues, 31%; and acne, 18%. Notably, most respondents had experienced tinnitus or hearing impairment attending concerts (61%) and clubs (43%). Only 14% of respondents had used earplugs; however, many could be motivated to try ear protection if they were aware of the potential for permanent hearing loss (66%) or were advised by a medical professional (59%). CONCLUSIONS: A majority of young adults have experienced tinnitus and hearing impairment after exposure to loud music. Fortunately, many of these individuals could be motivated to wear ear protection. This novel web-based survey technique rapidly generated a large database and is a feasible method to obtain health data from this group.

Adolescent↗

Tissue-engineered cartilage as a graft source for laryngotracheal reconstruction: a pig model.

OBJECTIVE: To evaluate the feasibility of using tissue-engineered cartilage for laryngotracheal reconstruction in the pig model. DESIGN: Auricular cartilage was harvested from 3 young swine. The cartilage was digested, processed, and suspended and a cell culture was obtained. The cells were then suspended in 3 mL of a 30% solution of a biodegradable polymer (Pluronic F-127) (polyethylene oxide/polypropylene oxide copolymer) at a cellular concentration of 50 x 10(6) cells/mL. This suspension was then implanted subcutaneously into each pig's dorsum. Eight weeks after implantation, the cartilage was harvested with the surrounding perichondrial capsule. An anterior cartilage graft laryngotracheal reconstruction was performed. Bronchoscopy was performed at 3 postoperative weeks to demonstrate airway patency. The animals were killed at 3 months, and specimens were obtained for histological analysis. SETTING: An animal research facility. SUBJECTS: Three young Yorkshire swine. RESULTS: All 3 pigs survived to the 3-month postoperative interval with no evidence of stridor or airway distress. Interval bronchoscopy revealed a normal patent airway with a mucosalized graft. Histopathologic analysis revealed incorporation of the tissue-engineered cartilage graft in the cricoid area, which correlated with results of bronchoscopic evaluation. CONCLUSION: Tissue-engineered auricular cartilage served as a viable graft in the pig model and might be an alternative cartilage source for laryngotracheal reconstruction.

Animals↗

Microtia chondrocytes as a donor source for tissue-engineered cartilage.

OBJECTIVES/HYPOTHESIS: Current surgical techniques for the correction of microtia are challenging. Research in the field of tissue engineering is providing insight into chondrocyte behavior for a possible future treatment of microtia. The authors wished to evaluate the biological potential of chondrocytes isolated from microtia cartilage as compared with normal auricular cartilage as a source of tissue-engineered cartilage. STUDY DESIGN: A comparative research design to study the potential of microtia cartilage chondrocytes with normal auricular chondrocytes as a source of tissue-engineered cartilage. METHODS: Cartilage specimens from 12 pediatric patients (six normal auricular specimens and six auricular specimens with microtia) were obtained. The chondrocytes were isolated and cultured in vitro; chondrocyte number was increased by passaging. Each type of cell was implanted in nude mice to generate tissue-engineered cartilage. Eight weeks after implantation the specimens were dissected and removed. Results were compared between the normal auricular and microtia specimens in regard to cell number expansion in vitro and generation of tissue-engineered cartilage in vivo. RESULTS: An initial mean cell number of 150,000 cells in each group (normal and microtia) increased to an average cell number of 120 million cells/mL in the normal and 130 million cells in the microtia subgroups, respectively, at the end of the second passage. Histologically, both types of chondrocytes generated normal elastic cartilage. CONCLUSION: The study demonstrated the potential of cells isolated from microtia cartilage to generate tissue-engineered cartilage. Microtia cartilage represents an important additional donor source for the possible generation of a human tissue-engineered auricle.

Case-Control Studies↗

Normal features of tissue-engineered auricular cartilage by flow cytometry and histology: patient safety.

BACKGROUND: Cytokinetic abnormalities in DNA content, such as aneuploidy, haploidy, and tetraploidy, have been found to occur in human cartilaginous tumors. The high number of chondrocytes needed for tissue-engineered cartilaginous implants requires the cells to be passaged repeatedly. The theoretical risk of changes in the normal diploid state of these cells during their growth in vitro and after generation of tissue-engineered cartilage in vivo is not known. Materials and methods Auricular chondrocytes were obtained from 6 patients and cultured in vitro. Chondrocyte number was increased by repeated passaging. The passaged cells were implanted in nude mice for 8 weeks to generate tissue-engineered cartilage. Fresh control chondrocytes along with the passaged cells and cells obtained from the tissue-engineered constructs were collected and compared for DNA content by flow cytometry. RESULTS: Flow cytometry demonstrated 100% diploidy with no evidence of aneuploidy, haploidy, or tetraploidy in all groups of cells. Histology of the tissue-engineered cartilage also showed no evidence of cellular atypia. CONCLUSION: The number of human auricular chondrocytes can be increased by repeated passaging and passaged chondrocytes can be safely used for implantation to generate tissue-engineered constructs without a change in the normal diploid state of the cells. Histology of the cartilage generated showed normal features without atypia.

Aneuploidy↗

In vitro tissue engineering to generate a human-sized auricle and nasal tip.

OBJECTIVES/HYPOTHESIS: Tissue engineering has successfully generated cartilage in a xenograft and an autograft model. However, challenges remain with both of these in vivo techniques before clinical application can be realized. We hypothesized that a human-sized cartilaginous structure could be generated completely in vitro as a complementary or an alternative technique. METHODS: Scaffolds were created in the shape of five full-sized human auricles and five nasal tip cartilaginous skeletons. Bovine shoulder chondrocytes at a concentration of 50 million cells/mL were seeded onto the scaffolds and were grown for 12 weeks in vitro. Two of the auricular scaffolds had internal support provided by soft acrylic sheets and were later implanted into nude rats. RESULTS: All of the scaffolds maintained shape and size through 12 weeks of in vitro culture. On gross examination the scaffolds were progressively replaced by cartilage, which was confirmed by histological and biochemical analysis. The auricular scaffolds with the acrylic internal support had the most natural rigidity, which was observed by gentle palpation. The nasal scaffolds maintained excellent definition even without internal support. CONCLUSION: An adult human-sized auricle and nasal tip cartilaginous structure can be grown entirely in vitro using principles of tissue engineering.

Animals↗

Laser therapy for refractory myringitis in children.

OBJECTIVE: We present the application and initial results of a CO(2) laser technique for the treatment of medically refractory chronic granular myringitis (CGM). STUDY DESIGN AND SETTING: Retrospective case series of 15 treated ears in 13 consecutive patients between the ages of 6 and 14 years (median age, 9.0 years) cared for in a tertiary care specialty hospital. RESULTS: Eleven of 15 treated ears had total resolution of CGM and associated symptoms; median follow-up time was 10 months. Three ears were improved, and 1 ear remained unchanged. Three of 5 preoperative tympanic membrane perforations healed after laser treatment; 1 patient developed a postoperative, dry perforation. Hearing was not impaired in any patient tested. CONCLUSION: Preliminary results suggest that CGM, when refractory to medical treatment, can often be treated effectively by a single laser treatment.

Adolescent↗

Role for interleukin 1alpha in the inhibition of chondrogenesis in autologous implants using polyglycolic acid-polylactic acid scaffolds.

Significant challenges remain in generating tissue-engineered cartilage in immunocompetent animals. Scaffold materials such as polyglycolic acid lead to significant inflammatory reactions, inhibiting homogeneous matrix synthesis. This study examined the generation of tissue-engineered cartilage, using a polyglycolic acid-polylactic acid copolymer (Ethisorb; Ethicon, Norderstedt, Germany) in an autologous immunocompetent pig model. The goals of this study were to determine the role of interleukin 1alpha (IL-1alpha) in this system and to assess the effect of serum treatment on tissue generation. Porcine auricular chondrocytes were seeded onto Ethisorb disks cultured for 1 week in medium supplemented with either fetal bovine serum or serum-free insulin-transferrin-selenium supplement. Specimens were implanted autogenously in pigs with unseeded scaffolds as controls. After 1, 4, or 8 weeks, six specimens from each group were explanted and analyzed histologically (hematoxylin and eosin, safranin O, trichrome, and Verhoeff's staining) and biochemically (glycosaminoglycan content). The presence and distribution of IL-1alpha were assessed by immunohistochemistry. Histology revealed acute inflammation surrounding degrading scaffold. Cartilage formation was observed as early as 1 week after implantation and continued to increase with time; however, homogeneous matrix synthesis was not present in any of the specimens. Strong IL-1alpha expression was detected in chondrocytes at the implant periphery and in cells in the vicinity of degrading polymer. Histologically there was no significant difference between the experimental groups with respect to the amount of matrix synthesis or inflammatory infiltration. The glycosaminoglycan content was significantly higher in the serum-free group. These results suggest that inflammatory reactions against scaffold materials and serum components lead to the production of cytokines such as IL-1alpha that may inhibit cartilage tissue formation in autologous transplant models.

Absorbable Implants↗