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Endovascular brachytherapy: effect on acute inflammatory response after percutaneous femoropopliteal arterial interventions.

PURPOSE: To investigate whether endovascular brachytherapy diminishes vascular inflammation in response to femoropopliteal percutaneous transluminal angioplasty (PTA) or stent implantation in two double-blind randomized-controlled trials. MATERIALS AND METHODS: Forty-seven consecutive patients from two double-blind randomized-controlled trials were studied. Patients either underwent femoropopliteal PTA with endovascular gamma irradiation (n = 8) or placebo irradiation (n = 7) or underwent PTA and stent implantation with brachytherapy (n = 15) or placebo irradiation (n = 17). High-sensitivity C-reactive protein (CRP), serum amyloid A (SAA), and fibrinogen levels were measured at baseline and 8, 24, and 48 hours after the intervention. The change of acute phase parameters from baseline to 48 hours after intervention indicated the extent of the inflammatory response and was compared between patients undergoing brachytherapy and those undergoing placebo irradiation. Fisher exact test was used for comparison of categorical data, and nonparametric statistical methods were applied for analysis of continuous data (Mann-Whitney U tests for unpaired data and Friedman analysis for repetitive measurements). RESULTS: Median patient age was 70 years (interquartile range, 56-74 years); 33 (70%) patients were men and 14 (30%) were women. Clinical characteristics and baseline values of acute phase parameters were similar between groups. A statistically significant increase in CRP, SAA, and fibrinogen values was observed after PTA and stent implantation, both in the patients who underwent brachytherapy and in those who underwent placebo irradiation. Compared with placebo irradiation, however, brachytherapy did not significantly reduce any acute phase parameter from baseline to 8, 24, or 48 hours after the intervention (P >.05 for all comparisons). CONCLUSION: Endovascular brachytherapy did not diminish early vascular inflammation in response to PTA or stent implantation and even induced a trend toward an increased inflammatory response.

Acute-Phase Reaction↗

Multi-detector row CT angiography of pulmonary circulation with gadolinium-based contrast agents: prospective evaluation in 60 patients.

PURPOSE: To prospectively evaluate gadolinium dose safety and effectiveness for 16-detector pulmonary computed tomographic (CT) angiography. MATERIALS AND METHODS: Ethics committee approval and informed consent were obtained. Sixty patients with contraindications to iodine underwent CT of the pulmonary circulation with 0.5 mmol/L gadolinium chelate given at either 0.3 (n = 29, group A) or 0.4 (n = 31, group B) mmol/kg; clinical and biologic tolerances were evaluated. Enhancement of central and segmental pulmonary arteries was measured (poor enhancement, <100 HU; good, 100-150 HU; excellent, >150 HU). Subsegmental artery enhancement was assessed as similar or inferior to that of segmental arteries. Confidence in analysis of the pulmonary arterial bed was graded according to arterial enhancement: Grades 1-3, diagnostic images; grade 4, nondiagnostic. The main effectiveness parameter for comparison between groups A and B was diagnostic value of CT angiograms. Nonparametric statistics were used to analyze results. RESULTS: The mean (+/- standard deviation) contrast material volume was 50.09 mL +/- 8.45 (all patients: range, 30-64 mL; group A: 46.54 mL +/- 8.59; group B: 53.42 mL +/- 6.92). Diagnostic images were obtained in 55 (92%) patients, and confident analysis of pulmonary arteries to the subsegmental level was achieved in 26 (grade 1, 44%) and to the segmental level, in 21 (grade 2, 35%). Mean attenuation was higher in group B than in group A in central (180.61 HU +/- 53.85 vs 148.14 HU +/- 52.61; P = .04) and segmental (201.59 HU +/- 54.70 vs 164.73 HU +/- 59.26; P = .03) arteries. Number of diagnostic CT angiograms was higher (P = .02) in group B (n = 31 [100%]) than in group A (n = 24 [83%]). In both groups, mean enhancement of pulmonary arteries was significantly higher at 80 or 100 kV than at 120 kV. Renal function was impaired in two group A patients. CONCLUSION: Gadolinium chelates may be used as an alternative CT contrast agent in patients who cannot receive iodine.

Adult↗

Variability in microleakage observed in a total-etch wet-bonding technique under different handling conditions.

Using a stereoscopic clearing protocol and scanning electron microscopy, we investigated the extent and nature of microleakage in a total-etch, current-generation dentin adhesive by a wet-bonding technique under different handling conditions. The hypotheses were that inadequate light curing of the primer or incomplete drying of the primer solvent might adversely affect the sealing ability of an acetone-containing adhesive system. The study consisted of three experimental groups: (I) a control group with an adequate light source and with the primer solvent completely dried; (II) an "inadequate-light" group; and (III) an "incomplete evaporation of primer solvent" group. The extent of microleakage after silver staining and clearing of the specimens was scored based on a modified five-point scale. Nonparametric statistical analysis (Kruskal-Wallis ANOVA) followed by a multiple comparison test (Dunn test) indicated significant differences among the three groups (p < 0.05). SEM examination of the restorative interface revealed that microleakage appeared to be initiated from the bonding resin-hybrid layer interface in all three groups, representing the weak link in the adhesive system. In addition, microleakage was characterized by 5 zones, each delineating a stage in a continuous array of progressively deleterious microleakage patterns variously distributed among the three groups. It was suggested that, while the bonding resin-hybrid layer interface represented the intrinsic weakness in an already much improved dentin adhesive, extrinsic factors such as the adequacy of the curing light and, more importantly, complete removal of the primer solvents can and should be avoided to preserve the structural integrity of the marginal seal.

Acid Etching, Dental↗

Whole blood heparin concentrations do not correlate with plasma antifactor Xa heparin concentrations in pediatric patients undergoing cardiopulmonary bypass.

This study was designed to test the validity of whole blood heparin concentration (WHBC) measurements using an on-site protamine titration assay with the Hepcon instrument (Medtronic Blood Management, Parker, CO, USA) in pediatric patients less than 1 year old undergoing cardiopulmonary bypass (CPB). The validity of the Hepcon measurements was examined via a test of correlation with the gold standard plasma antifactor Xa activity (anti-Xa) assay. Fifty-one patients (23 females and 28 males) under 1 year old (mean age 5.3 months) were studied prospectively. Blood samples were taken at 5 min into CPB and at the end of CPB for the WBHC, plasma anti-Xa activity, and hematocrit (Hct). The WBHC was converted to plasma heparin level using a formula taking into account the collection of blood into citrate solution and the effect of the citrate on the hematocrit. While a nonparametric statistical analysis revealed that the mean corrected values from the Hepcon instrument were not significantly different from the mean anti-Xa values (p = 0.070 at 5 min on CPB, p = 0.518 at the end of CPB), there was no significant correlation between these values at either 5 min into CPB (r = 0.113, p = 0.429) or at the end of CPB (r = -0.247, p = 0.080). The lack of correlation between the two assays may be related to the extreme hemodilution observed during CPB in small children, which leads to very low concentrations of coagulation proteins. Due to this discrepancy, whole blood heparin monitors should be further evaluated in children undergoing CPB.

Anticoagulants↗

A data review and re-assessment of ovarian cancer serum proteomic profiling.

BACKGROUND: The early detection of ovarian cancer has the potential to dramatically reduce mortality. Recently, the use of mass spectrometry to develop profiles of patient serum proteins, combined with advanced data mining algorithms has been reported as a promising method to achieve this goal. In this report, we analyze the Ovarian Dataset 8-7-02 downloaded from the Clinical Proteomics Program Databank website, using nonparametric statistics and stepwise discriminant analysis to develop rules to diagnose patients, as well as to understand general patterns in the data that may guide future research. RESULTS: The mass spectrometry serum profiles derived from cancer and controls exhibited numerous statistical differences. For example, use of the Wilcoxon test in comparing the intensity at each of the 15,154 mass to charge (M/Z) values between the cancer and controls, resulted in the detection of 3,591 M/Z values whose intensities differed by a p-value of 10-6 or less. The region containing the M/Z values of greatest statistical difference between cancer and controls occurred at M/Z values less than 500. For example the M/Z values of 2.7921478 and 245.53704 could be used to significantly separate the cancer from control groups. Three other sets of M/Z values were developed using a training set that could distinguish between cancer and control subjects in a test set with 100% sensitivity and specificity. CONCLUSION: The ability to discriminate between cancer and control subjects based on the M/Z values of 2.7921478 and 245.53704 reveals the existence of a significant non-biologic experimental bias between these two groups. This bias may invalidate attempts to use this dataset to find patterns of reproducible diagnostic value. To minimize false discovery, results using mass spectrometry and data mining algorithms should be carefully reviewed and benchmarked with routine statistical methods.

Artificial Intelligence↗

Endothelial selectins in acute mountain sickness and high-altitude pulmonary edema.

STUDY OBJECTIVES: Mechanical or inflammatory injury to pulmonary endothelial cells may cause impaired pulmonary gas exchange in acute mountain sickness (AMS) and noncardiogenic pulmonary edema in high-altitude pulmonary edema (HAPE). This study was designed to determine whether markers of endothelial cell activation or injury, plasma E- and P-selectin, were increased after ascent to high altitude, in AMS or in HAPE. DESIGN: We collected clinical data and plasma specimens in control subjects at sea level and after ascent to 4,200 m, and in climbers with AMS or HAPE at 4,200 m. Data analysis was performed using standard nonparametric statistical methods, and results reported as mean+/-SD. SETTING: National Park Service medical camp at 4,200 m on Mt. McKinley (Denali), Alaska. PATIENTS: Blood samples and clinical data were collected from 17 healthy climbers at sea level and again after ascent to 4,200 m, and from a different group of 13 climbers with AMS and 8 climbers with HAPE at 4,200 m. Climbers with AMS were divided into normoxic (n=7) and hypoxemic (n=6) groups. MEASUREMENTS AND RESULTS: Using an enzyme immunoassay technique, plasma E-selectin concentrations were found to be increased in the 17 control subjects after ascent to 4,200 m (17.2+/-8.2 ng/mL) as compared to sea level (12.9+/-8.2 ng/mL) (p=0.001). Plasma E-selectin concentrations were also increased in subjects with hypoxemic AMS (30.6+/-13.4 ng/mL) and HAPE (23.3+/-9.1 ng/mL) compared to control subjects at sea level (p=0.009). Increased plasma E-selectin concentration significantly correlated with hypoxemia (p=0.006). Plasma P-selectin concentrations were unchanged after ascent to 4,200 m and in subjects with AMS and HAPE. CONCLUSION: Because E-selectin is produced only by endothelial cells, increased plasma E-selectin after ascent to high altitude and in hypoxemic climbers with AMS and HAPE provides evidence that endothelial cell activation or injury is a component of hypoxic altitude illness.

Acute Disease↗

Dimensional personality profiles of borderline personality disorder in comparison with other personality disorders and healthy controls.

The present study examined the sensitivity and clinical specificity of dimensional personality profiles associated with borderline personality disorder (BPD) by comparing three groups of patients: (a) patients with BPD according to DSM-IV criteria (n = 31); (b) patients with other DSM-IV PD (n = 31); and (c) general population controls (n = 31). All three samples were matched for age and gender and the two patient samples were matched for chronicity and depressive symptoms. All patients were given the Six-Factor Test measuring the five-factor model of personality (FFM), the Temperament and Character Inventory (TCI), and the Dimensional Assessment of Personality Pathology (DAPP). Nonparametric statistics were applied to analyze the data (Mann-Whitney-U-tests for group comparisons; Spearman's coefficients for correlational analyses). Neuroticism (FFM), Self-Directedness (TCI), and Emotional Dysregulation (DAPP) were identified as general markers of personality pathology, which were significantly interrelated in all three samples. BPD patients also showed a specific profile compared with other PD patients with lower scores on Agreeableness (FFM), higher scores on Novelty Seeking and Self-Transcendence (TCI), and higher scores on the DAPP higher-order dimensions of Emotional Dysregulation, Dissocial Behavior, and Inhibitedness. Results support the assumption that BPD can be characterized by dimensional approaches with sufficient sensitivity in comparison with healthy controls and specificity in comparison with other PD patients.

Adult↗

Image quality in digital radiographic systems.

The aim of the present study was to evaluate the image quality of four direct digital radiographic systems. Radiographs were made of the maxillary central incisor and mandibular left molar regions of a dry skull, and an aluminum step-wedge. The X-ray generator operated at 10 mA. 60 and 70 kVp, and images were acquired with 3, 5, 8, 12, 24 and 48 exposure pulses. Six well-trained observers classified the images by means of scores from 1 to 3. Collected data were submitted to nonparametric statistical analysis using Fisher's exact test. Statistical analysis showed significant differences (p < 0.01) in image quality with the four systems. Based on the results, it was possible to conclude that: 1) all of the digital systems presented good performance in producing acceptable images for diagnosis, if the exposures of the step-wedge and the maxillary central incisor region were made at 5 pulses, as well as at 8 pulses for the mandibular left molar region, selecting 60 or 70kVp; 2) higher percentages of acceptable images were obtained with the administration of lower radiation doses in CCD-sensors (charge-coupled device); 3) the Storage Phosphor systems produced acceptable images at a large range of exposure settings, that included low, intermediate and high radiation doses.

Humans↗

Serum beta2-microglobulin values among healthy Brazilians using a DPC IMMULITE assay.

PURPOSE: The present study was designed to determine the normal range of serum beta 2-microglobulin (Sb2M) levels among healthy volunteers in Brazil. Levels of Sb2M are elevated in human immunodeficiency virus (HIV)-infected patients and have been shown to be the best predictor of HIV infection status and of some malignant disorders, especially multiple myeloma. In order to achieve its optimal use in Brazilian clinical diagnosis, an adequate reference interval study was performed for Sb2M IMMULITE assay, based on the fact that its reference range limits were evaluated among European populations. METHODS: Ninety-six healthy blood donors were evaluated, and Sb2M levels were measured by chemiluminescent enzyme immunoassay using the IMMULITE automated analyzer. RESULTS: A normal range of Sb2M values, established by a nonparametric statistical method, was 1.05 to 3.9 mg/mL, with the upper limit being higher than that reported elsewhere. CONCLUSIONS: This study presented new data indicating that there is a significant difference between the current reference limits for Sb2M IMMULITE assay and those found in Brazil, providing evidence that significant differences in range of normal values may occur among different populations, and that these new values should be considered for Brazilian individuals.

Adult↗

Kangaroo mother care during phototherapy: effect on bilirubin profile.

PURPOSE: To determine the safety and efficacy of allowing kangaroo mother care (KMC) one hour per day during the course of phototherapy using a fiberoptic phototherapy panel. SAMPLE: Thirty premature infants, 30-35 weeks gestation, <2,500 gm, who required phototherapy. Infants were randomized into three groups: (1) infants who received traditional bank or spotlight phototherapy 24 hours per day, (2) infants who received traditional phototherapy 23 hours per day and for the 24th hour lay prone on a fiberoptic phototherapy panel, and (3) infants who received traditional phototherapy 23 hours per day and for the 24th hour were given KMC with a fiberoptic phototherapy panel held against their back. OUTCOME VARIABLES: Nonparametric statistics were used for between-group comparisons on number of days of phototherapy, daily bilirubin decrement, and bilirubin profiles over the course of phototherapy. RESULTS: Groups did not differ in the number of days of phototherapy or in daily mean bilirubin decrement. The bilirubin profile for the KMC group showed a more shallow descent than did the profiles for the other groups, but a significant difference in decline was present only on day 4 of treatment (p = .05). CONCLUSION: This pilot work suggests that KMC using a fiberoptic panel during phototherapy may be safe, but further study is needed.

Bilirubin↗

Differences regarding job satisfaction and job involvement of psychologists with different dominant career anchors.

In order to contribute to higher levels of job satisfaction, job involvement and productivity, a match or fit should be established between the dominant career anchor associated with a specific occupation and that of the employee. A career anchor is an individual's set of self-perceived talents, abilities, motives, needs and values that form the nucleus of one's occupational self-concept. Psychologists have always been part of the service orientated careers and therefore one would expect that it is likely that their dominant career anchor would be service orientation. If this is the case, psychologists with service as their dominant career anchor are supposed to have greater job satisfaction and job involvement compared to those with different career anchors. However, according to literature, this assumption is not necessarily correct. The primary goals of the current study were to determine whether in fact service is the dominant career anchor of psychologists in the Free State and whether there are significant differences regarding job satisfaction and job involvement between psychologists with and without service as their dominant career anchor. A third goal was to determine whether psychologists with different dominant career anchors differ significantly from one another regarding job satisfaction and job involvement. Questionnaires measuring career orientations, job satisfaction and job involvement were sent to 165 of the 171 registered psychologists in the Free State region. Only 75 psychologists (45,5%) responded which exceeded the traditional return rate of 20 to 30%. Due to the small sample of respondents, a nonparametric statistical test, namely the Mann Whitney U test was conducted to determine possible differences. An analysis of the data showed that 21 respondents had entrepreneurship as their dominant career orientation while 12 fell in the technical/functional, 12 in the challenging, 9 in the service and 8 in the autonomy categories of dominant career anchors. No significant differences regarding job satisfaction between psychologists with and without service as dominant career orientation could be determined. Both groups experienced a fairly high degree of job satisfaction and a higher level of intrinsic job satisfaction occurred compared to extrinsic job satisfaction. A significant difference between the two groups in terms of job involvement occurred. Psychologists with service as dominant career orientation showed a higher level of job involvement, although the degree of job involvement for both groups was fairly low. No significant differences regarding job satisfaction and job involvement among psychologists with different career orientations could be found.

Adult↗

Occupational therapists' use and perceptions of written client education materials.

OBJECTIVE: The purpose of this study was to examine occupational therapists' use and perceptions of written education materials for clients and the factors that therapists consider before distributing written materials to clients. This study also aimed to determine whether use and perceptions of these materials differed for older clients. METHOD: A random sample of 50 occupational therapists from Queensland, Australia, working in adult physical disabilities settings was surveyed with a structured questionnaire. Data were analyzed descriptively and with nonparametric statistics. RESULTS: Of 49 participants who used written materials, 54% had given them to more than half of their last 10 clients, regardless of the clients' age. Written materials, most often information sheets developed by the participants themselves; handwritten notes; and pamphlets were principally used to reinforce verbal information. Clients' cognitive abilities, primary language, communication skills, vision, and level of education most often were considered before distributing written materials. Although participants generally were positive about the content and effectiveness of materials, ratings were significantly less positive related to older clients. CONCLUSION: Client education was a core treatment modality for participants in this study, with written media most commonly being used to supplement verbal education. Because participants were least positive about the effectiveness of written materials for older clients, further development of materials for this audience may be indicated.

Adult↗

Exposure-response of asphalt fumes with changes in pulmonary function and symptoms.

OBJECTIVES: This study examines possible associations between asphalt fumes and workshift changes in lung function and symptoms among 170 workers exposed to asphalt fumes. METHODS: The workers were from 5 segments of the asphalt industry, and most of them participated for 2 consecutive workdays. The primary response variables were changes in lung function (measured at the beginning and end of the shift) and incidence of symptoms (measured before, 3 times during, and at the end of the shift). Exposure was estimated from breathing-zone samples of total particulate (TP), respirable particulate (RP), the benzene-soluble fraction of the TP (BSF), volatile hydrocarbons collected on a charcoal tube (VHC), nitrogen dioxide, sulfur dioxide, formaldehyde, carbon monoxide, and hydrogen sulfide. Ozone and wet bulb/dry bulb temperature, as a measure of heat stress, were measured as area samples. In addition, daily cigarette smoking was determined by questionnaire. The exposure-response associations were assessed by both parametric and nonparametric statistical techniques. RESULTS: Overall, no consistent association was observed between an acute reduction in lung function or the incidence of symptoms and exposure to asphalt fumes. Concentrations in the neighborhood of the maximum levels constitute no-observed adverse effect levels: TP (<1.5 mg/m3 to maximum 6.2 mg/m3), RP (<0.6 mg/m3 to maximum 1.4 mg/m3), BSF (<0.6 mg/m3 to maximum 1.3 mg/m3), VHC (<8 mg/m3 to maximum 19.8 mg/m3). There were no exposure-response trends with ozone, heat stress, cigarettes smoked, or length of workday.

Adolescent↗

Oral conditions in children with cerebral palsy.

PURPOSE: Cerebral palsy (CP) is a major severe childhood disability and its prevalence is increasing, particularly among premature low-weight newborns. The oral conditions observed demonstrate the need for home and professional care for these individuals. This study aimed to investigate dental caries, plaque index, time of eruption, malocclusion, bruxism and motor oral skills in a group of 62 CP children (study group). METHODS: The results were compared to those obtained for a control group with 67 normal children. Nonparametric statistical tests including the Mann-Whitney test, Fisher's Exact test (P), Chi-square test (chi2), and Cochran's Q test were used according to the nature of the variables studied, with the level of significance set at P<.05. RESULTS: The results showed a significantly higher DMFS index for CP children with permanent dentition of both sexes when compared to normal children. A significantly higher plaque index was also observed in the study group. A high tendency to delayed eruption of permanent molars and significantly higher percentages of malocclusion and bruxism were observed in the study group with permanent dentition. Residual food and mouth breathing have been frequently found in CP children. CONCLUSIONS: Earlier preventive measures for CP patients are required because they are a high-risk group for dental caries.

Adolescent↗

Research in pediatric dental postgraduate programs and residencies: results of a survey.

PURPOSE: The purpose of this study was to determine various aspects of the research experiences in postgraduate and residency training programs in pediatric dentistry. METHODS: A survey was developed and sent to all directors of postgraduate and residency training programs in pediatric dentistry. The survey consisted of 21 items on various topics related to research experiences of the postgraduate students and residents. The items varied in structure, but most contained response sets deemed appropriate for the intent of the question. The directors were asked to complete the survey and return the questionnaire in a self-addressed stamped envelope within a 3-week period. If a program did not respond within 6 weeks, a follow-up survey was sent. The response sets were collated and analyzed with descriptive and nonparametric statistics. RESULTS: Forty of 55 programs responded with usable data sets. All reporting programs indicated that research experiences occur for residents and all have access to statistical assistance. Eighty-seven percent devote clinical hours to student research and 50% of the students share data or protocols. Only a minority (7%) of programs has not published student research in the last 5 years. Interference with revenue-generating clinic times (45%), lack of faculty understanding/interest in research (40%), and lack of financial resources (32%) were the 3 major obstacles for postgraduate research. CONCLUSIONS: Despite research being accomplished in postgraduate programs in pediatric dentistry, variability in key factors (eg, devoted research time) is common among programs. The impact of this variability on the profession and its advancement of scientific endeavors are unknown.

Attitude of Health Personnel↗

SEM analysis of internal adaptation of adhesive restorations after contamination with saliva.

PURPOSE: This study tested the null hypothesis that different treatments of saliva-contaminated substrate would not affect microgap formation at the dentin walls of bonded restorations. MATERIALS AND METHODS: Forty freshly extracted human molars received standardized Class V preparations on buccal and lingual surfaces. The specimens were assigned to four experimental groups (n = 20): [G1] no contamination (control group), [G2] saliva contamination (10 s) after etching followed by 5 s air stream; [G3] saliva contamination after etching and rinsed for 10 s; and [G4] re-etching for 10 s after saliva contamination. All specimens were restored with a one-bottle adhesive (Single Bond, 3M ESPE) and microhybrid composite resin (Filtek Z250, 3M ESPE) according to the manufacturer's instructions. The specimens were thermocycled, sectioned through the center of the restoration, and then processed for SEM. Microgaps were measured at the axial wall at 1500X magnification. The data were submitted to Kruskal-Wallis nonparametric statistical analysis at p < 0.05. RESULTS: The data revealed that different groups resulted in a statistically significant difference (p < 0.01) in gap formation. Air drying [G2] and rinsing [G3] the saliva-contaminated dentin resulted in similar microgap values (p > 0.05). However, re-etching the dentin after saliva contamination [G4] increased microgap formation (p < 0.05) when compared with the groups G1 and G2. Although air drying and rinsing produced results comparable to noncontaminated dentin, the presence of microgaps was not completely eliminated. CONCLUSION: Contaminated saliva did not prevent hybrid layer formation; however, it did reduce the adaptation of the restorative material to bonded surfaces.

Acid Etching, Dental↗

Blink reflexes in patients with atypical odontalgia.

AIMS: To use the human blink reflex (BR) to explore possible neuropathic pain mechanisms in patients with atypical odontalgia (AO). METHODS: In 13 AO patients, the BR was elicited using a concentric electrode and recorded bilaterally with surface electromyographic (EMG) electrodes on both orbicularis oculi muscles. Electrical stimuli were applied to the skin above branches of the V1, V2, and V3 nerves and to the V branch contralateral to the painful branch. Sensory and pain thresholds were determined. The BR examination of the painful V branch was repeated during a capsaicin pain-provocation test. The data were analyzed with nonparametric statistics. RESULTS: The BR responses (R2 and R3) evoked by stimulation of V3 were significantly smaller than the BR responses evoked by stimulation of V1 and V2 (P < .004). There were no differences in BR (R2 or R3) between the painful and nonpainful sides (P > .569), and the BR (R2 and R3) was not significantly modulated by experimental pain (P > .080). The sensory thresholds were significantly lower on the painful side compared to the nonpainful side (P = .014). The pain thresholds were not different between sides (P > .910). CONCLUSION: No major differences between the V nociceptive pathways on the right and left sides were found in a relatively small group of AO patients. Future studies that compare BRs in AO patients and healthy volunteers are needed to provide further knowledge on the pain mechanisms in AO.

Adult↗