Biomedical subjects

Karen H Calhoun

Publications and source records attributed to Karen H Calhoun.

7 recordsLinked to original sources

PubMed2004

Patterns of mold sensitivity in the subtropical Gulf Coast.

OBJECTIVES: We sought to determine the patterns of mold- and nonmold positive skin tests in a subtropical Gulf Coast climate and to determine whether any particular positive skin tests predict "allergic versus nonallergic" status as shown on the full panel of skin testing. STUDY DESIGN AND SETTING: We conducted a retrospective evaluation of serial endpoint allergy skin test results in 75 consecutive patients from a tertiary referral medical center. RESULTS: Of the 67 evaluable patients, 58 (86.6%) had a positive skin test to at least 1 antigen. The most common positive skin tests were in response to cockroach, Dermatophygoides farinae, Bermuda grass, false ragweed, mesquite, Stemphylium, Curvularia, short ragweed, and Timothy grass. There were no identifiable groups of antigens that tended to occur together. Screening with a panel of 6 antigens (cockroach, dust mite, cat, rough marsh elder, Timothy grass, and Stemphylium) would have correctly predicted whether the patient would react to any or none of the full panel of antigens. CONCLUSION: Cockroach, dust mite, and a grass were the most common positive skin tests among our patients, with many patients also having positive skin tests to molds. Although there is evidence that cross-reactivity exists among different mold species, we were unable to identify any clusters of mold reacting together in individual patients. In our patient population, a 6-allergen screening panel (cockroach, dust mite, cat, rough marsh elder, Timothy grass, and Stemphylium) would have accurately distinguished "allergic" from "nonallergic" patients, as demonstrated on the full panel of skin testing. SIGNIFICANCE: A small (6-antigen) screening panel accurately predicted "allergic" versus "nonallergic" as shown by our full panel of skin testing. This is useful clinically when an "allergic versus nonallergic" etiology of sinonasal symptoms affects treatment choices.

Adult↗

PubMed2004

Smoking in chronic rhinosinusitis: a predictor of poor long-term outcome after endoscopic sinus surgery.

OBJECTIVE: This study was designed to determine whether smoking patients have poorer outcomes after endoscopic sinus surgery (ESS) based on a reliable validated rhinosinusitis-specific quality-of-life outcomes test. STUDY DESIGN: Retrospective chart and computed tomography (CT) review with telephone and letter questionnaire. METHODS: Charts of 230 adult patients undergoing ESS for chronic rhinosinusitis between January 1995 and December 1998 were reviewed. Each participating patient completed a detailed questionnaire, including the Sino-Nasal Outcome Test-16 (SNOT-16), at an average of 52 months after surgery. Preoperative CT scans were reviewed and the findings used to stage the patients' conditions. Multivariate analysis was used to assess these data. RESULTS: Eighty-two patients completed the questionnaire, with 26 who smoked at the time of surgery and continued to smoke at the time of answering the questionnaire (Smokers). Average SNOT-16 score in Smokers was 27.5, versus 18.2 in those who did not smoke at the time of surgery (Non-Smokers). There was a statistically significant correlation between elevated SNOT-16 scores and smoking (P <.001) and antibiotic use within the past year (P <.001). There was an association between high SNOT-16 scores and both prior smoking and passive smoke exposure that did not reach statistical significance (P =.055 and P =.267, respectively). CT staging scores and prior ESS were not statistically correlated with SNOT-16 scores. CONCLUSIONS: Smoking is associated with statistically worse outcomes after ESS based on average SNOT-16 scores. Although no investigator has proved that the effects of smoking on sinonasal health are reversible, we counsel smoking patients considering ESS about the desirability of smoking cessation (for this and many health reasons), and the possibility of a poorer postsurgery outcome should they continue smoking.

Chronic Disease↗

PubMed2003

Treatment and outcome of human bites in the head and neck.

OBJECTIVE: Our goal was to review head and neck human bite injuries for demographic, treatment, and outcome data to identify factors influencing infection. Study design Retrospective chart review of all human bite injuries (adult and pediatric) over 10 years. SETTING: Tertiary referral medical center. RESULTS: We reviewed 40 human bites (average follow-up, 139 days). Young males were the most common victims, altercation was the most common etiology, and auricular avulsion was the most common injury. Six wounds closed primarily became infected (40%) versus no wound infection with delayed closure. Primary wound closure (P <.01), exposed cartilage (P <.07), and less than 48 hours of intravenous antibiotics (P <.06) were associated with postoperative infection (P <.01). CONCLUSION: Human bites to the head and neck, especially those with exposed cartilage, are best treated with at least 48 hours of intravenous antibiotics and delayed surgical closure (>24 hours postinjury) to prevent infection. SIGNIFICANCE: This information enables the clinician who sees these bite wounds infrequently to understand the treatment associated with avoiding infection.

Adult↗

PubMed2003

Bone that best matches the properties of the mandible.

OBJECTIVE: The main advantage of primary oromandibular reconstruction using free vascularized bone-containing flaps is improved oral function from (1) the maintenance of mandibular and soft tissue architecture and (2) dental rehabilitation through osseointegrated implants. Bone dimensions, volume, quality, and the ability of the bone to withstand masticatory forces are important factors in achieving successful osseointegration. Previous studies have objectively examined the dimensions of bones used in oromandibular reconstruction, but few have addressed their biomechanical properties. The purpose of this study was to compare the dimensional and biomechanical properties of the bones commonly used in oromandibular reconstruction with those of the mandible. METHODS: Eleven formalin-fixed cadavers were used. The mandibles, fibulae, iliac crests, scapulae, clavicles, second metatarsals, radii, and anterior ribs were harvested. Measurements of the dimensions of the bones were made with calipers at multiple sites. Three-point break strength and screw pulling force tests were then performed on all of the bones. RESULTS: The fibulae, iliac crests, and clavicles had dimensions that best matched those of the mandible. The three-point break strength and screw pulling force tests were consistently the highest for the mandibles and fibulae, followed by the clavicles, scapulae, iliac crests, metatarsals, radii, and ribs, in that order. CONCLUSIONS: The fibula is the bone that best matches the properties of the mandible.

Aged↗

PubMed2002

Digital image archiving.

The digital camera has become a valuable component of the clinical practice for many otolaryngologist head and neck surgeons. Because several technical details distinguish digital cameras from their standard 35-mm counterparts, having some knowledge of these features is crucial for integrating digital imaging successfully into a practice. This chapter discusses these cameras and digital output, with an emphasis on their use in a medical practice. The author also explores current and future applications and gives a summary of limitations and benefits.

Computer Storage Devices↗

PubMedDate not supplied

The effect of tension on patency of rat femoral artery anastomoses.

OBJECTIVE: To determine experimentally the role of tension in the failure of microarterial anastomoses. METHODS: Sixteen microarterial anastomoses were performed in femoral arteries from adult Sprague-Dawley male rats after resecting 0, 1, 2, or 3 mm. The percentage of vessel excised was calculated. The vessel was then examined in approximately 1 week for patency. Next, 5 femoral arteries were excised and length-tension curves generated. RESULTS: All vessels were patent in which less than 20% of the length was resected. Clinically, only vessels under extreme tension failed. Length-tension curves suggested 2 zones of vessel extensibility with a breakpoint between them. Extension of the vessel beyond this breakpoint required extreme tension. CONCLUSIONS: Moderate tension at a microarterial anastomosis does not lead to anastomotic failure. Failure occurs after the elastic reserve of the vessel is exceeded.

Anastomosis, Surgical↗

PubMedDate not supplied

Optimal design of O-to-Z flaps for closure of facial skin defects.

OBJECTIVE: To determine the optimal design of an O-to-Z flap for closure of facial skin defects. METHODS: Prospective cadaver study. Multiple 2-cm-diameter circular skin defects were created in fresh cadavers. Three types of O-to-Z flaps were designed, varying the angle of a curved line about concentric radii of the defect: acute, intermediate, or wide angle flap. The tension of closure of each was measured and compared at different lengths of incision and extents of undermining. RESULTS: The acute angle flap had a significantly lower closing tension at all lengths of incision and extents of undermining than the intermediate and wide angle flaps. Increasing the amount of undermining alone without incising the flap did not significantly decrease the closing tension. Incising the acute angle flap to 4 radii created a nearly tension-free closure. CONCLUSIONS: The optimal design for reducing tension of the O-to Z flap is an acute angle flap. The optimal length of incision and undermining necessary to minimize closing tension is discussed.

Cadaver↗