Biomedical subjects

P Shaman

Publications and source records attributed to P Shaman.

10 recordsLinked to original sources

PubMed1995

Tibial nonunion treated with direct current, capacitive coupling, or bone graft.

Two hundred seventy-one tibial nonunions of average duration of 23.5 months (range, 9-69 months) were treated with direct current (167 patients), capacitive coupled electrical stimulation (56 patients), or bone graft surgery (48 patients). Logistic regression analysis was used to compare heal rates among the 3 treatment methods, to identify risk factors adversely affecting the heal rate, and to predict the probability of successful healing of a nonunion of any given risk profile treated with each of the 3 forms of therapy. Seven risk factors were identified: duration of nonunion, prior bone graft surgery, prior electrical treatment, open fracture, osteomyelitis, comminuted or oblique fracture, and atrophic nonunion. When no risk factors were present, there were no significant differences among the 3 treatment methods. As progressively more risk factors were present, the predicted heal rates decreased significantly regardless of the treatment method. Some differences among the treatment groups did appear in the heal rates: bone graft surgery yielded a worse heal rate when there was a previous bone graft failure, and capacitive coupling had a worse heal rate in the presence of an atrophic nonunion.

Adult↗

PubMed1994

Complications of ethmoidectomy: a survey of fellows of the American Academy of Otolaryngology-Head and Neck Surgery.

A survey regarding complications of sinus surgery was mailed to 6969 otolaryngologists; 3933 responses (56.44%) were obtained, and 3043 of these physicians (77.37%) reported that they performed ethmoidectomy. Completed questionnaires were available for review from 42.21% of all Academy fellows (2942 physicians). Responses were tabulated and summarized question by question. Physicians generally did not rate their residency training in ethmoidectomy highly. The survey confirmed that there has been a marked rise in the frequency of ethmoidectomy and in the amount of training in ethmoidectomy since 1985. Empirical complication rates were calculated for different procedures and time periods. Poisson regression models were then constructed to describe the rate of complications under varying conditions such as the type of surgery performed, time period, experience and training of the surgeon, and type of complication encountered. The models permitted determination of the statistical significance of variables in relation to incidence or complications. The study did not demonstrate a clear and consistent statistical relationship between the incidence of complications, the type of surgery performed, and the quality of training. Moreover, physicians who provided data from record review tended to report higher rates than those who estimated responses. The majority of physicians discussed specific potential complications with their patients before surgery and routinely performed preoperative computed tomography. The study demonstrated that physicians who experienced complications at higher rates were more likely to discuss these complications with patients before surgery.

Ethmoid Sinus↗

PubMed1993

Chorioretinal folds. A comparison of unilateral and bilateral cases.

We retrospectively reviewed the records, photographs, and fluorescein angiograms of patients with chorioretinal folds to compare features of unilateral and bilateral involvement. We studied 78 eyes of 54 patients and found that 30 (56%) of these patients had unilateral folds and 24 (44%) had bilateral folds. No significant difference was found in comparing visual acuity, refractive error, age, or race in the unilateral vs the bilateral cases. There were significantly more women in the bilateral group (P = .043). The frequency of causes of unilateral cases differed from bilateral cases, but this could not be statistically proven owing to our small sample size. This analysis contains the largest number of chorioretinal folds reported in the literature, and is the first attempt to compare unilateral and bilateral cases.

Adolescent↗

PubMed1991

Smell and taste disorders, a study of 750 patients from the University of Pennsylvania Smell and Taste Center.

Smell and taste disorders are common in the general population, yet little is known about their nature or cause. This article describes a study of 750 patients with complaints of abnormal smell or taste perception from the University of Pennsylvania Smell and Taste Center, Philadelphia. Major findings suggest that: chemosensory dysfunction influences quality of life; complaints of taste loss usually reflect loss of smell function; upper respiratory infection, head trauma, and chronic nasal and paranasal sinus disease are the most common causes of the diminution of the sense of smell, with head trauma having the greatest loss; depression frequently accompanies chemosensory distortion; low body weight accompanies burning mouth syndrome; estrogens protect against loss of the sense of smell in postmenopausal women; zinc therapy may provide no benefit to patients with chemosensory dysfunction; and thyroid hormone function is associated with oral sensory distortion. The findings are discussed in relation to management of patients with chemosensory disturbances.

Burning Mouth Syndrome↗

PubMed1991

Photochemical effects of laser irradiation on neuritic outgrowth of olfactory neuroepithelial explants.

The photochemical effect of low-intensity laser irradiation (LILI) on the maturation and regeneration of olfactory-immature estrus day 15 (E15) and olfactory-mature estrus day 22 (E22) rat fetuses was studied. Neuritic outgrowths of olfactory bipolar receptor cells were quantified in olfactory neuroepithelial explants. Explants in the experimental groups were irradiated with a helium-neon laser using different incident energy densities (IEDs). Explants in another group were exposed to fluorescent light. Control explants did not receive laser or fluorescent light irradiation. Neuritic outgrowths were analyzed on a regular basis for 12 days. Analysis of variance was used to evaluate the data. The parameters of neuritic outgrowth in E15 fetuses showed a significant increase of 30% to 50% vs. the control with a single laser irradiation of 0.5 J/cm2 IED. The rate of neuritic outgrowth observed in the E22 fetuses was less than in the E15 fetuses. The parameters of neuritic outgrowth in E22 fetuses showed a significant and substantially greater percentage increase than in the E15 fetuses with daily laser irradiations of 0.05 and 0.5 J/cm2 IED when compared to the control. The magnitude of these increases appears to be of biological significance as well as statistical significance.

Analysis of Variance↗

PubMed1984

Smell identification ability: changes with age.

Smell identification ability was measured in 1955 persons ranging in age from 5 to 99 years. On the average, women outperformed men at all ages, and nonsmokers outperformed smokers. Peak performance occurred in the third through fifth decades and declined markedly after the seventh. More than half of those 65 to 80 years old evidenced major olfactory impairment. After 80 years, more than three-quarters evidenced major impairment. Given these findings, it is not surprising that many elderly persons complain that food lacks flavor and that the elderly account for a disproportionate number of accidental gas poisoning cases each year.

Adolescent↗

PubMed1984

Topographic coding of odorant quality is maintained at different concentrations in the salamander olfactory epithelium.

In a recent study in the tiger salamander, Ambystoma tigrinum, were demonstrated topographic patterns of responsivity across the olfactory epithelium which were characteristic for each odorant. The present study was initiated to investigate whether these patterns remain constant when odorant concentration is varied. Odorant-induced electro- olfactograms were recorded from at least 12 sites on each epithelium. The odorants used were pinene, amyl acetate and propanol. Each epithelium was tested with one odorant, delivered at 3 concentrations. For comparison between animals, the epithelia were divided into 3 regions with at least 4 recording sites per region. An analysis of variance model was used to study odorants, concentrations, regions and animals. Odorant-induced regional patterns in responsivity were similar across all concentrations. In particular, the region of highest responsivity at one concentration was the region of highest responsivity at all concentrations. It is concluded that topographic patterns of receptor cell responses may reflect an underlying genetic component in the distribution of receptor cells. This distribution is related to two aspects of receptor cell responses: responsivity to particular odorants (Fig. 4) and general responsivity to all odorants (Fig. 5).

Ambystoma↗

PubMed1984

Development of the University of Pennsylvania Smell Identification Test: a standardized microencapsulated test of olfactory function.

The development of the first standardized "scratch 'n sniff" olfactory test is described. Over 1600 subjects participated in five experiments. In Experiment 1, 50 microencapsulated odorants were rated as to their intensity, pleasantness, irritation, coolness, and familiarity, and two procedures for releasing them were compared. In Experiment 2, the results of the first experiment and other data were used in the development of the test, which was administered to a large number of subjects. Using multiple regression analysis, scores on this test were shown to be significantly related to the subjects' gender, ethnic background, and smoking behavior. Average test scores decreased as a function of age, with the greatest decline occurring between the sixth and tenth decades of life. These age-related changes were not correlated with scores on the Wechsler Memory Scale. Women performed better than men within all age categories. In Experiment 3, the test was shown to differentiate between subjects with known olfactory disorders (e.g., Kallmann's syndrome; Korsakoff's syndrome) and normal controls, and to reliably detect persons instructed to feign total anosmia. In Experiment 4, the test-retest reliability was established (6-month interval; r = 0.918, p less than 0.001), and in Experiment 5 the test was shown to correlate thresholds with odor detection (r = -0.794, p less than 0.001). This self-administratered test now makes it possible to rapidly and accurately assess general olfactory function in the laboratory, clinic, or through the mail without complex equipment or space-consuming stores of chemicals.

Adolescent↗

PubMed1984

University of Pennsylvania Smell Identification Test: a rapid quantitative olfactory function test for the clinic.

Despite the fact that clinical otolaryngologists are often presented with complaints of olfactory dysfunction, they have limited means to diagnose these problems. A major reason has been the lack of a clinically-useful and reliable quantitative test of olfactory function. Recent work at our Clinical Research Center has resulted in the development of such a test. This test--the University of Pennsylvania Smell Identification Test (UPSIT)--can be self-administered and uses microencapsulated odorants which are released by scratching standardized odor-impregnated test booklets. As indicated in this paper, studies have demonstrated that the UPSIT can identify most malingerers and is sensitive to age, gender, smoking habits, and a wide variety of olfactory disorders. A description of this new test, along with some of its applications, is presented.

Humans↗

PubMed1982

Topographic coding of olfactory quality: odorant-specific patterns of epithelial responsivity in the salamander.

1. Electrophysiological recordings were made on the ventral olfactory epithelium of the salamander Ambystoma tigrinum in order to investigate whether individual odorants can elicit unique patterns of receptor neuron responses. 2. Slow transepithelial voltage transients, Veog(-), were recorded from 30 sites on each epithelium. For each odorant a topographic pattern was derived from the Veog(-) amplitudes across the 30 recording sites. 3. Nine odorants were tested, each in seven animals, and topographic patterns of Veog(-) amplitudes were drawn for each animal. Due to the morphological variability among animals, the electrode sites for each animal were assigned to six epithelial regions for which responses were then compared by analysis of variance. 4. Odorant-specific regional differences in responsivity were observed. The odorants can be grouped according to the similarity of the topographic distributions of responses elicited by them. We observed that no two odorants elicited exactly the same response patterns. This suggests that olfactory receptor neurons with similar responses are grouped together in the same region of the epithelium. 5. Dramatic differences in responsivity among the various epithelial regions, irrespective of the test odorant, were also noted. This observation may be due to regional differences in receptor neuron density or overall sensitivity. 6. It is concluded that differences between the topographic distributions of receptor cell responses, elicited by the nine test odorants, permits these responses to be discriminated as unique patterns of information at the olfactory bulb.

Ambystoma↗