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PubMed2004

Association between the TPH gene A218C polymorphism and suicidal behavior: a meta-analysis.

Genes encoding proteins involved in serotonergic metabolism are major candidates in association studies of suicidal behavior. The tryptophan hydroxylase (TPH) gene, which codes for the rate-limiting enzyme of serotonin biosynthesis, is a major candidate gene and has been extensively studied in association studies of suicidal behavior, providing conflicting results. It is difficult to interpret these conflicting results due to lack of power, ethnic heterogeneity, and variations in the sampling strategies (in particular for controls) and in the polymorphism of the TPH gene studied. Meta-analyses can improve the statistical power for the analysis of the effects of candidate vulnerability factors. The analysis of the sources of heterogeneity that contribute to these conflicting results is an important step in the interpretation of these conflicting association results and in the interpretation of the results of a meta-analysis. We selected all of the published association studies between the TPH gene polymorphism and suicidal behavior. Nine association studies between the A218C TPH polymorphism and suicidal behavior fulfilled the inclusion criteria. A significant association was observed between the A218C polymorphism and suicidal behavior using the fixed effect method (odds ratio (OR) = 1.62; 95% confidence interval (CI) = [1.26; 2.07]) and the random effect method (OR = 1.61; 95% CI = [1.11; 2.35]). The analysis of the sources of heterogeneity showed that two studies (one positive and one negative) significantly deviated from the calculated global effect. The meta-analysis performed after removing those two studies also revealed a significant association between the TPH A218C polymorphism and suicidal behavior. Both analyses suggested that the A allele has a dose-dependent effect on the risk of suicidal behavior.

Alleles↗
PubMed2006

Gender difference analysis of cortical thickness in healthy young adults with surface-based methods.

We have examined gender differences of cortical thickness using a 3-D surface-based method that enables more accurate measurement in deep sulci and localized regional mapping compared to volumetric analyses. Cortical thickness was measured using a direct method for calculating the distance between corresponding vertices from inner and outer cortical surfaces. We normalized cortical surfaces using 2-D surface registration and performed diffusion smoothing to reduce the variability of folding patterns and to increase the power of the statistical analysis. In stereotaxic space, significant localized cortical thickening in women was found extensively in frontal, parietal and occipital lobes, including the superior frontal gyrus (SFG), superior parietal gyrus (SPG), inferior frontal gyrus (IFG) and postcentral gyrus (PoCG) in the left hemisphere and mostly in the parietal lobe, including the SPG in the right hemisphere. In the temporal lobe, small regions of the left and right caudal superior temporal gyrus (STG) and the left temporal pole showed significantly greater cortical thickness in women. The temporal lobe shows relatively less significant thickening than other lobes in both hemispheres. In native space, significantly greater cortical thickness in women was detected in left parietal region, including SPG and PoCG. No significant local increases of cortical thickness were observed in men in both spaces. These findings suggest statistically significant cortical thickening in women in localized anatomical regions, which is consistent with several previous studies and may support a hypothesis of sexual dimorphism.

Adolescent↗
PubMedDate not supplied

Chorioamnionitis does not affect fetal urine production in patients with premature rupture of membranes.

The objective of this study was to evaluate fetal urine production rate in patients with premature rupture of membranes in the presence or absence of chorioamnionitis and to determine its clinical usefulness. Fetal urine production was evaluated in 30 women between 24 and 39 weeks' gestational age with ruptured membranes. Fetal bladder measurements were determined every 3-5 min for 30-90 min. Chorioamnionitis was defined by both clinical criteria and histological examination of the placenta. The last determination of fetal urine production rate prior to delivery was compared in patients with and without histologic and/or clinical chorioamnionitis. Fetal urine production rate was corrected for gestational age using birth weight prior to analysis. A total of 96 assessments of fetal urine production were performed (range 1-16 per patient). Twelve subjects (40%) had no evidence of chorioamnionitis (group 1), 10 (33%) had histologic chorioamnionitis alone (group 2), and eight (27%) had both clinical and histologic chorioamnionitis (group 3). The mean (+/- SD) urine production rates in these groups were 9.43 +/- 3.15 ml/kg/hr, 10.65 +/- 3.43 ml/kg/hr, and 9.97 +/- 2.81 ml/kg/hr, respectively. The difference in fetal urine production rate between the three groups was not statistically significant. A power analysis revealed that individual group sizes were adequate to document a 50% increase in fetal urine production rate with a type II error of < 10%. There were no documented cases of fetal infection based on neonatal cultures. The presence of histologic or clinical chorioamnionitis does not significantly affect fetal urine production in patients with premature rupture of membranes. The prospective assessment of fetal urine production rate does not appear to be clinically useful as an early indicator of chorioamnionitis.

Chorioamnionitis↗
PubMedDate not supplied

Evaluation of an educational program in preventive cardiology.

In 1979, an educational program in preventive cardiology (PC), supported by the National Heart, Lung, and Blood Institute (NHLBI) was introduced into the medical school at the University of Tennessee, Memphis (UTM). This report evaluates that program from 1979 to 1984 in terms of student health behaviors, student attitudes toward PC, student knowledge of PC, and the impact of the program on continuing development of educational programs in PC. In 1981, using a 30% random sample, freshmen students in medicine and dentistry at UTM and medical students at a nearby state medical school similar to UTM were surveyed concerning health behaviors, attitudes, and knowledge. The surveys were repeated three years later. Analysis of the data from these pre- and postsurveys showed that UTM medical students improved (P less than .05) their attitudes about the preventability of heart disease and that their PC knowledge scores increased (P less than .0001). Personal health habits and health parameters were generally good and remained so. Although control medical students improved their PC knowledge, this change was not as great as in UTM medical students (P less than .05). The improved attitude toward PC in UTM medical students was not statistically different from changes in control students. Unfortunately, the statistical power of this analysis was low (less than 20%), and important differences between UTM medical students and controls were likely to have been missed. In addition to changes in students, considerable institutional change occurred at UTM as a direct result of this project, leading to the expansion of emphasis on PC (and prevention in general) in the five years since the completion of this NHLBI-funded program.

Cardiology↗
PubMed1984

Evidence for the superiority of immunosuppressive drugs and prednisone over prednisone alone in lupus nephritis. Results of a pooled analysis.

In an effort to clarify the role of immunosuppressive drugs in the management of lupus nephritis, we pooled data from all published clinical trials in which patients had been randomly assigned to receive either prednisone alone or prednisone plus cyclophosphamide or azathioprine. The pooled analysis showed that patients receiving immunosuppressive drugs had less renal deterioration (P = 0.006), were less likely to have end-stage renal disease (P = 0.023), and were less likely to die from kidney disease (P = 0.024) than patients receiving steroids alone. There were no significant differences with respect to deaths from nonrenal causes or overall mortality. When cyclophosphamide and azathioprine were considered separately, both were associated with a 40 per cent reduction in the rates of adverse renal outcomes, although because the treatment groups were smaller, many of these differences were not statistically significant. A power analysis showed that a study of 100 high-risk patients (development of renal insufficiency in 50 per cent) would be needed to prove that an immunosuppressive agent is 50 per cent superior to steroids alone in preventing renal deterioration. We conclude that immunosuppressive drugs and steroids together are more effective than steroids alone in treating lupus nephritis and that published trials have reached false negative conclusions because of small sample sizes.

Azathioprine↗
PubMed2006

A meta-analytic comparison of preoperative stress echocardiography and nuclear scintigraphy imaging.

In this meta-analysis we compared thallium imaging (TI) and stress echocardiography (SE) in patients at risk for myocardial infarction (MI) scheduled for elective noncardiac surgery. Two searches of published articles were used to identify relevant articles. We included all studies that stated the criteria for a positive test and detailed the frequency of postoperative MI and in-hospital death. Data were abstracted by two authors and captured preoperative patient characteristics, study design, blinding, and outcome adjudication. We defined a positive test as a test with a reversible defect and, where possible, quantified the size of the defects in each study. MI and/or death were the only postoperative outcomes of interest. We calculated the sensitivity, specificity, and likelihood ratio (LR) and, where possible, the Receiver Operating Characteristic (ROC) curve of a cardiac event in each study. The LR and ROC were combined by meta-analyses using the random effects model. Heterogeneity was assessed using the I2 test. The search revealed 68 studies of 10,049 patients. There were 25 SE studies and 50 TI studies. There were 7 studies with a direct comparison of the two methodologies. The quality of studies differed; routine screening for MI was used more frequently in SE studies (47.8% versus 21.2%; P = 0.008) and screening dictated treatment more often after TI (72.1%) than after SE (46.3%) (P = 0.027). The LR for SE was more indicative of a postoperative cardiac event than TI (LR, 4.09; 95% CI, 3.21-6.56 versus 1.83; 1.59-2.10; P = 0.001). This difference was attributable to fewer false-negative SEs. There was no difference in the cumulative ROC curves from qualitative studies (SE, 0.80; 95% CI, 0.76-.84 versus TI, 0.75; 95% CI, 0.70-081). Again, the LR for a negative SE was less (0.23; 95% CI, 0.17-0.32 versus 0.44; 95% CI, 0.36-0.54). A moderate-to-large defect, seen in 14% of patients, by either method predicts a postoperative cardiac event (LR, 8.35; 95% CI, 5.6-12.45). This meta-analysis possesses the statistical power to demonstrate that SE has better negative predicative characteristics than TI. A moderate-to-large perfusion defect by either SE or TI predicts postoperative MI and death. We conclude the SE is superior to TI in predicting postoperative cardiac events.

Confidence Intervals↗
PubMed2000

A clinical trial investigating the possible effect of the supine cervical rotatory manipulation and the supine lateral break manipulation in the treatment of mechanical neck pain: a pilot study.

OBJECTIVE: To evaluate the possible effect of the supine cervical rotary manipulation and the supine lateral break manipulation in the treatment of mechanical neck pain, according to subjective and objective clinical findings. BACKGROUND: Delivering a supine lateral break manipulation to the ipsilateral side of an inflamed facet joint(s) that exhibits a lateral flexion fixation may result in pain and/or discomfort to the patient. Thus the proposed alternative is a supine cervical rotary manipulation delivered on the ipsilateral side or a supine lateral break manipulation delivered on the contralateral side of the relevant joint(s). DESIGN: Randomized, comparative clinical trial. SUBJECTS: Two groups of 15 subjects diagnosed with mechanical neck pain. INTERVENTION: The diagnosis of mechanical neck pain and the identification of lateral flexion fixations in the cervical spine were made with conventional clinical evaluation, including motion palpation. Group A received a cervical rotary manipulation(s) on the ipsilateral side of the lateral flexion fixation(s), while group B received a supine lateral break manipulation(s) on the contralateral side of the lateral flexion fixation(s). Subjects received a maximum of 10 treatments over a 4-week treatment period. OUTCOME MEASURES: Both treatment groups were assessed with subjective (Numerical Pain Rating Scale 101, McGill Short-Form Pain Questionnaire and the Canadian Memorial Chiropractic College Neck Disability Index) and objective (cervical range of motion goniometer and algometer) measurement parameters at the initial consultation (before any treatment), the final consultation, and at a 1-month follow-up consultation. Statistical analysis was conducted at a 95% confidence level (alpha =.05) with the non-parametric 2-tailed Wilcoxon signed ranks test, the Mann-Whitney U test, and descriptive statistics. Two-tailed power analysis was conducted after the fact, where a confidence level of 80% (beta =.20) was considered satisfactory. RESULTS: Intragroup analysis indicated a significant difference between the initial consultation data and the final consultation data for the subjective data, indicating an effect. Analysis of the objective data did not reveal any significant difference. Intergroup analysis did not reveal any significant difference between the 2 groups when comparing the data of the initial consultation and the final consultation, indicating that both treatments had a similar or equal effect. Power analysis was not satisfactory for most data, indicating the possibility of many Type II errors. CONCLUSION AND RECOMMENDATIONS: Statistically, the results suggested that both treatments had an effect but that neither group showed a benefit over the other. However, because of the unsatisfactory power of the study, conclusions are to be drawn with caution. Clinical significance supported the statistical outcomes where it was suggested that both treatments had an effect and that neither treatment had a greater effect. A larger sample size and the inclusion of a placebo group is recommended to reveal true treatment outcomes and trends.

Adolescent↗
PubMed2004

Relationship between pressure fluctuations and generation of organic pollutants with different particle size distributions in a fluidized bed incinerator.

The hydrodynamic behaviors of fluidization perhaps significantly influence the uniformity of fluidization in fluidized bed incinerator. Good uniformity of fluidization expressed the air across uniformly through the bed and the particles being distributed well in the fluid stream. The aggregates, flocs and channels of particles do not happen during fluidization. The Good uniformity will maintain high heat and mass distribution to improve reaction efficiency. These parameters include the height of static bed, gas velocity, mixing and distribution of bed particle, which have rarely been studied in previous investigations. Consequently, this study examines how the hydrodynamic parameters affect the generation of organic pollutants (BTEXs and PAHs) during incineration. The statistical and power spectral analysis of the measured pressure fluctuation during incineration are used to elucidate the relationship between behaviors of fluidization and generation of pollutants during incineration. Experimental results show the organic concentration does not increase with uniformity of fluidization decreasing. The reason may be the explosion of the gas and the consequent thermal shock destroy the coalescent bubbles to form small bubbles again and enhance the efficiency of transfer of oxygen to increase combustion efficiency. Additionally, the mean amplitude and fluidized index of pressure fluctuation similarly vary with the concentration of organic pollutants. These two indices can be used to assess the efficiency of combustion. The four particle size distributions could be divided into two groups by statistical analysis. The Gaussian and narrow distributions belong to one group and the binary and flat the other. The organic concentration of the Gaussian and narrow distributions are lower than that of the other distributions. Consequently, the bed materials should maintain narrow or Gaussian distributions to maintain a good combustion efficiency during incineration.

Benzene Derivatives↗
PubMed2000

Susceptibility-induced loss of signal: comparing PET and fMRI on a semantic task.

Functional magnetic resonance imaging (fMRI) has become a popular tool for investigations into the neural correlates of cognitive activity. One limitation of fMRI, however, is that it has difficulty imaging regions near tissue interfaces due to distortions from macroscopic susceptibility effects which become more severe at higher magnetic field strengths. This difficulty can be particularly problematic for language tasks that engage regions of the temporal lobes near the air-filled sinuses. This paper investigates susceptibility-induced signal loss in the temporal lobes and proposes that by defining a priori regions of interest and using the small-volume statistical correction of K. J. Worsley, S. Marrett, P. Neelin, A. C. Vandal, K. J. Friston, and A. C. Evans (1996, Hum. Brain Mapp. 4: 58-83), activations in these areas can sometimes be detected by increasing the statistical power of the analysis. We conducted two experiments, one with PET and the other with fMRI, using almost identical semantic categorization paradigms and comparable methods of analysis. There were areas of overlap as well as differences between the PET and fMRI results. One anticipated difference was a lack of activation in two regions in the temporal lobe on initial analyses in the fMRI data set. With a specific region of interest, however, activation in one of the regions was detected. These experiments demonstrate three points: first, even for almost identical cognitive tasks such as those in this study, PET and fMRI may not produce identical results; second, differences between the two methods due to macroscopic susceptibility artifacts in fMRI can be overcome with appropriate statistical corrections, but only partially; and third, new data acquisition paradigms are necessary to fully deal with susceptibility-induced signal loss if the sensitivity of the fMRI experiment to temporal lobe activations is to be enhanced.

Adult↗
PubMed1999

Angiogenesis during mandibular distraction osteogenesis.

Recruitment of a blood supply is critical for successful bone induction and fracture healing. Despite the clinical success of distraction osteogenesis (DO), an analysis of angiogenesis during membranous bone DO has not been performed. The purpose of this study was to evaluate the temporal and spatial pattern of angiogenesis during mandibular DO. The right hemimandible of adult male rats was osteotomized, and a customized distraction device was applied. Following a 3-day latency period, distraction was begun at a rate of 0.25 mm twice daily for 6 days (3.0 mm total; 12% increase in mandibular length). Three animals each were sacrificed on days 2, 4, and 6 of distraction (D1, D2, and D3 respectively), or after 1, 2, or 4 weeks of consolidation (C1, C2, and C3 respectively). Two experienced pathologists reviewed the regenerate histology, and angiogenesis was assessed by counting the number of blood vessels per intermediate-power field (IPF). Statistical analysis was performed using analysis of variance, with p < or = 0.05 considered significant. Results demonstrate that mandibular DO was associated with an intense vascular response during the early stages of distraction (D1). On average, 31.5+/-7.9 vessels were noted in each IPF examined during this time point. The number of blood vessels in the distraction regenerate decreased significantly during the later distraction time points, with approximately 14.0+/-2.0 and 14.7+/-3.5 blood vessels per IPF in sections obtained after days 4 and 6 of distraction (D2, D3) respectively. However, blood vessels at these time points took on a more mature histological pattern. During the consolidation period, the number of blood vessels noted in the regenerate decreased with 8.0+/-2.6, 9.3+/-2.1, and 4.0+/-2.0 vessels per IPF in sections obtained after 1, 2, or 4 weeks of consolidation (C1, C2, C3) respectively (p < 0.05 compared with vessel counts during the earliest distraction time point). This study demonstrates for the first time that an intense vascular response associated with mandibular DO occurs primarily during the early stages of distraction. The authors hypothesize that as distraction continues, newly formed vessels likely undergo consolidation, thus forming more mature vessels capable of withstanding distraction forces. Future studies will assess the effects of therapeutic interventions designed to increase angiogenesis during DO on bony regenerate formation.

Animals↗
PubMed1999

Bioequivalence review for drug interchangeability.

To monitor the performance of the approved generic copies of a brand-name drug, we propose some methods in assessing bioequivalence among generic copies and the brand-name drug, and among generic copies themselves, using data from several bioequivalence studies adopting the standard 2 x 2 crossover design without carryover effects. We propose a meta-analysis method that increases statistical power when the between-subject variability is not large. A nonmeta-analysis is also considered. A numerical example of applying both methods is presented for illustration.

Area Under Curve↗
PubMed2000

Steroids for multiple sclerosis and optic neuritis: a meta-analysis of randomized controlled clinical trials.

We conducted a meta-analysis of randomized controlled clinical trials on steroid treatment for multiple sclerosis and optic neuritis. Of the 25 trials comparing steroids and controls without steroid treatment that we identified 12 were selected for this review. A meta-analysis was conducted to calculate the overall odds ratio across the studies for the numbers of patients without functional improvement and with new relapses. The trials included a total of 1714 patients: 998 with multiple sclerosis and 716 with optic neuritis. Any type of corticosteroids or adrenocorticotropic hormone (ACTH) treatment was considered, as was any dosage, route of administration, and length of treatment. Main outcome measures were: (a) number of multiple sclerosis patients who did not improve by at least one point on the EDSS or equivalent scale, or number of optic neuritis patients without complete recovery of visual acuity at 8 or 30 days and at longer follow-up; (b) number of multiple sclerosis patients with at least one new relapse, or number of optic neuritis patients in whom definite multiple sclerosis was diagnosed at longer follow-up. We found that corticosteroids or ACTH produced a significant improvement in disability or visual acuity at 30 days (odds ratio 0.49; 95% CI 0.37-0.64). The improvement was not statistically significant at longer follow-up (0.85; 95% CI 0.67-1.09). The treatment did not significantly reduce the number of patients with relapses (0.74; 95% CI 0.54-1.01). Both low and high doses were effective for 30-day improvement, but only high-dose and short-term therapy were factors that identified subgroups with some reduction in the risk of new relapse. However, the power of the statistical analysis to detect a reliable difference in the subgroups was low. Steroid treatment is therefore effective in accelerating short-term recovery in patients with multiple sclerosis or optic neuritis. Whether steroids are also effective in reducing the risk of relapse, and the optimal dose and length of treatment must still be determined.

Disability Evaluation↗
PubMed2004

Identification of candidate antigens for serologic detection of Helicobacter pylori-infected patients with gastric carcinoma.

Helicobacter pylori colonizes the stomach of almost half the world population and is a causative agent of gastric carcinomas and duodenal ulcers. Only a small fraction of infected people will develop these severe illnesses and a predictive test to identify people at high risk would greatly benefit disease management. Our study aimed to identify conserved bacterial antigens that may be useful for the development of such a diagnostic test. High-resolution immunoproteomics by 2-dimensional electrophoresis of H. pylori 26695 proteins was carried out with sera from infected patients with either duodenal ulcer (n=30) or gastric carcinoma (n=30), 2 clinically divergent conditions. According to their antigen recognition patterns clear groups of patients were identified. Although this classification did not correspond to the clinical status, it may be correlated to other bacterial or host factors that influence the outcome of infection. In general antigen recognition patterns were found to be highly variable, however by utilizing powerful image analysis and statistical tests the recognition of 14 antigenic protein species was found to differ significantly (p<0.01) between both diseases. Particular protein species of GroEL, HyuA, GroES and AtpA appear to be useful surrogate markers for gastric carcinoma detection and consequently should be considered for further prospective studies to assess their predictive value. For one protein species of AtpA, evidence was found that different post-translational modifications may confer different immunogenicities.

Adenocarcinoma↗
PubMed1991

Response of the electric activity in the human stomach to water and a solid meal.

The gastric electric activity paces the contractions of the stomach and can be measured noninvasively using surface electrodes placed on the abdomen. In this paper, response of the gastric electric activity to water and a solid meal was investigated using surface electrodes. Applying an improved recording technique, power spectral analysis and statistical analysis methods, the gastric electric activity in preprandial, postwater and postprandial states was measured and analysed from ten healthy volunteers. To more convincingly show the effect of water and the solid meal on the gastric slow wave and gastric motility, simultaneous recordings of the cutaneous EGG and manometric activities in the stomach were performed in three gastroparetic patients. It was found that water does not induce contractions of the stomach, but the gastric slow wave amplitude increases (p less than 0.05) and frequency decreases (p less than 0.05). The solid meal results in an increase in both the amplitude (p less than 0.01) and the frequency (p less than 0.02) of the gastric slow wave. It appears that the postprandial EGG amplitude increases because of a combination of stomach contractions and gastric distension bringing the stomach closer to the recording electrodes. The slow wave frequency, however, correlates well with stomach contractions.

Adult↗
PubMed1997

[Combined breast-preserving surgery, chemotherapy and radiotherapy in the treatment of breast carcinoma. Effect of the interval between surgery and the beginning of radiotherapy].

BACKGROUND: The timing of breast conserving surgery, chemotherapy, and radiotherapy in breast cancer treatment has become the subject of increasing interest over the last years. PATIENTS AND METHOD: Seventy-four patients who underwent postoperative radiotherapy at our institution between 1985 and 1992 form the basis of this study. Median follow-up time was 5 years. Seventy-three percent of patients were pre- or perimenopausal. Almost all patients (91%) were UICC-stage II. Axillary lymph nodes were positive in 95% of cases. Complete gross resection was achieved in all patients, and in 65% final pathological margins were free of invasive or intraductal carcinoma. Postoperatively, 70% of patients received 6 cycles of polychemotherapy (predominantly CMF) before onset of irradiation. The radiation dose was in almost all cases 60 Gy including 10 Gy boost. RESULTS: Five years after start of treatment overall survival, disease-free survival, and local recurrence rates were 86% (95%-confidence limits, 76 to 93%), 73% (61 to 83%), and 8% (3 to 16%), respectively. For disease-free survival, the only significant prognostic factor was the number of involved lymph nodes: 0 to 3 = 86%, > or = 4 = 40% (p < 0.0001). The interval between surgery and radiation (< or = versus > 20 weeks) had no significant influence on disease-free survival or local tumor control. In contrast, there was a trend of increased regional and distant failure with shortening of the interval due to the delivery of less than 6 cycles chemotherapy before the onset of radiotherapy. CONCLUSIONS: In our experience, there was no negative impact of a delay of radiotherapy in order to deliver full course chemotherapy before initiation of radiotherapy. However, the low statistical power of this analysis due to the small number of patients must be considered. it appears possible that a less intense chemotherapy before starting radiation treatment correlates with enhanced distant failure and subsequently decreased disease-free survival rates. Therefore, for patients at increased risk for distant metastasis, we prefer to give 6 cycles polychemotherapy before irradiation.

Adult↗
PubMed1992

Beta irradiation of recurrent ptergia: results and complications.

Although postoperative beta irradiation for prevention of pterygium recurrence is widely used, its complication rate has not been widely appreciated. Thirty-six patients underwent pterygium excision followed by irradiation with 90Sr to between 1600 and 5300 cGy (median 2400) in two to four fractions over 7 to 27 days. A median of three fields were used in each treatment course (range two to 10). Most patients had undergone previous treatment for their pterygia, including surgery alone (25 patients), or both surgery and irradiation (5 patients). Overall, recurrences developed in 10 eyes (28%). Recurrence occurred in one eye after re-irradiation (20%), compared to 9 of 31 (29%) previously non-irradiated eyes (p greater than 0.1). There was no association with number of excisions and recurrences, although all but 6 patients had undergone more than one excision. Thirteen patients (36%) developed complications including: epithelial defect or corneal thinning (3), symblepharon (5), cataract (4) and corneal ulceration (1). Complications developed in 4 of the 5 (80%) re-irradiated eyes compared to 9 of 31 (29%) previously non-irradiated eyes (p less than 0.05). The power of the statistical analysis was limited by sample size, but no significant association was observed between the development of complications or recurrences and total dose, number of abutting fields, number of previous surgical excisions or patient age, even when re-irradiated patients were excluded. Recently described calibration uncertainties with the 90Sr applicator may explain in part these complications. Alternatively, technical factors such as the number of fields or volume treated may play a role. Excessive complications and recurrences with the use of postoperative beta irradiation in this series emphasize the danger of re-treatment and the need for alternative safe and effective therapies.

Adolescent↗
PubMed2004

Retrocapsular lens fragments after uneventful phacoemulsification cataract surgery.

PURPOSE: To analyze the factors influencing the risk for lens fragments in the retrocapsular space after uneventful phacoemulsification cataract surgery. SETTING: Norfolk and Norwich University Hospital, Norwich, United Kingdom. METHODS: Five hundred six consecutive patients who had uneventful phacoemulsification cataract surgery were examined intraoperatively for lens fragments in the retrocapsular space. Data collected for each patient included site of corneal incision, axial length, cataract nuclear density, phaco power and duration, and equivalent phaco time (EPT, calculated as a product of phaco power and duration). Statistical analysis was performed to determine the effect of each factor on the risk for developing retrocapsular lens fragments. RESULTS: Retrocapsular lens fragments were present in 16.6% of patients. Univariate analysis showed that the duration of phacoemulsification and EPT were significantly longer in patients with retrocapsular lens fragments than in those without. Logistic regression showed that EPT was the only factor statistically significantly associated with the fragments. However, the effect of EPT on the odds ratio of developing fragments was small. CONCLUSIONS: Lens fragments in the retrocapsular space occurred relatively frequently after uneventful phacoemulsification surgery. There was a small but statistically significant relationship between EPT and the risk for lens fragments.

Humans↗
PubMedDate not supplied

Arthroscopic rotator cuff repair with and without arthroscopic subacromial decompression: a prospective, randomized study of one-year outcomes.

We performed a prospective, randomized study to determine whether arthroscopic subacromial decompression changes the outcome of rotator cuff repair. We performed a power analysis to ensure statistical validity. Patients scheduled for arthroscopic rotator cuff repair were randomized to cuff repair with arthroscopic subacromial decompression (group 1) or without it (group 2). All other aspects of the surgical and postsurgical treatment were identical. We included patients with full-thickness tears limited to the supraspinatus tendon and a type 2 acromion. We excluded patients with prior surgery, those with larger tears involving two or more tendons, those with a type 1 or 3 acromion, those with workers' compensation claims, and those who had concomitant procedures (labral repair, acromioclavicular joint resection) There were 47 patients in group 1 and 46 in group 2. Minimum follow-up was 1 year (mean, 15.6 +/- 3.3 months). We recorded the American Shoulder and Elbow Surgeons (ASES) shoulder scores preoperatively and postoperatively. There was no statistical difference in postoperative ASES scores between group 1 (91.5 +/- 10.3) and group 2 (89.2 +/- 15.1) (P =.392). The change in ASES score over time did not differ between the two groups (61.1 vs 60.2, P =.363). In conclusion, within the parameters described above, arthroscopic subacromial decompression does not appear to change the functional outcome after arthroscopic repair of the rotator cuff.

Adult↗