Sphincter-preserving surgery for rectal cancer: a population-based study in Taiwan.

BACKGROUND/AIMS: Sphincter-preserving surgery (SPS) has been considered a surrogate for surgical quality for rectal cancer. This study aims to assess its rate for rectal cancer between centers and over time in Taiwan. METHODOLOGY: Data from 1997 to 2006 on patients undergoing sphincter-preserving surgery (anterior resection or AR) and proctectomy with colostomy (abdominoperineal resection or APR) were extracted from a national health insurance database. Hierarchical logistic regression was used to identify independent factors associated with SPS. RESULTS: Data on 19,919 patients were analyzed. Among them, 12,164 (61%) received AR and 7,755 (39%) underwent APR at total of 115 centers. Multifactorial analysis revealed higher SPS rates with female gender (p<0.001) and patients paying higher insurance premiums (p=0.005). Higher APR rates were seen in those receiving surgery at metropolitan hospitals (p=0.001) and hospitals outside higher volume regions (Taipei City and North, p≦0.005). For hospitals with initial low surgical volumes, significant improvement of SPS rate was found (p<0.001) with increasing volume over the study period. CONCLUSIONS: The disparity due to sphincter loss in rectal cancer between hospitals of various regions and levels narrowed in Taiwan. Characteristics of hospital (level, region, volume) and patient (gender, premium level) influenced SPS rate.

Differences between children and adults with otitis media with effusion treated with CO(2) laser myringotomy.

BACKGROUND: The safety and advantages of CO(2) laser myringotomy for otitis media with effusion (OME) are well described. The goal of such treatment is to avoid unnecessary ventilation tube insertion. Comparisons between different age groups treated with this modality are lacking, and prognostic factors for treatment outcomes are not available. METHODS: We conducted a retrospective cohort study that included 130 children (160 ears) and 96 adults (108 ears) with OME persisting after conservative antibiotic treatment. In eligible patients, we performed laser myringotomy in the affected ear. Follow-up was scheduled every week for 1 month and then every month for 6 months. Results for 233 ears were available for analysis; 24 ears were excluded (19 due to cancer, four due to a cleft palate, and one due to Down syndrome) and 10 patients (11 ears) were lost during follow-up. A logistic regression model was used for analysis, with success of therapy as the binary outcome. RESULTS: Adult patients had more unilateral lesions (p < 0.001) and serous fluid effusions (p < 0.001) than did the pediatric patients. However, there was no significant difference in the cure rate (children: 58.1%; adults: 64.7%) and positive culture rate (children: 15.1%; adults: 14.3%) between patient groups. Three factors were found to be associated with a poor prognosis: multiple occurrences in children (p < 0.001), mucoid effusion (p = 0.04), and a history of ventilation tube use in adults (p < 0.001). No other variables predicted treatment outcome. CONCLUSION: Our findings suggest that CO(2) laser myringotomy is a useful treatment modality for OME in children and adults, except for children with multiple occurrences and in adults with mucoid effusions and a history of ventilation tube use.

The effects of continuous combined oral estradiol and norethisterone on pulsatility index in internal carotid and uterine arteries in early postmenopausal Taiwanese women---a preliminary study.

OBJECTIVE: This study analyzed whether continuous combined oral estradiol and norethisterone had any effect on the pulsatility index (PI) of the internal carotid and uterine arteries in Taiwanese early postmenopausal women. MATERIALS AND METHODS: A group of 40 healthy postmenopausal women with no history of hormone therapy (HT) participated in this study and were randomly subdivided into two groups: HT treatment group (n = 20) and placebo group (n = 20). PI was evaluated with color Doppler ultrasound at the beginning of the study and after 4 months of HT (2 mg 17beta-estradiol + 1 mg norethisterone acetate) or placebo. RESULTS: There was no significant change in the PI of the internal carotid and the uterine arteries after 4 months of HT. CONCLUSION: This HT regimen showed no significant negative impact on vascular resistance in Taiwanese early postmenopausal women. Results are compatible with the updated recommendations on HT stating that there is little cardiovascular risk when HT is initiated within a few years of the menopause.

A comparison of binary models dealing with an extraneous effect relating to the main risk factor, but not relating to the outcome variable.

In a binary model relating a response variable Y to a risk factor X, account may need to take of an extraneous effect Z that is related to X, but not Y. This is known as the association pattern Y-X-Z. The extraneous variable Z is commonly included in models as a covariate. This paper concerns binary models, and investigates the use of deviation from the group mean (D-GM) and deviation from the fitted fractional polynomial value (D-FP) for removing the extraneous effect of Z.In a simulation study, D-FP performed excellently, while the performance of D-GM was slightly worse than the traditional method of treating Z as a covariate. In addition, estimators with excessive mean square errors or standard errors cannot occur when D-GM or D-FP is employed, even in small or sparse data sets.The Y-X-Z association pattern studied here often occurs in fetal studies, where the fetal measurement (X) varies with the gestation age (Z), but gestation age does not relate to the outcome variable (Y; e.g. Down's syndrome). D-GM and D-FP perform well with illustrative data from fetal studies, although there is a weak association between X and Z with a lower proportion of case subjects (e.g. 11:1, control to case).It is not necessary to add a new covariate when a model deals with the extraneous effect. The D-FP or D-GM methods perform well with the real data studied here, and moreover, D-FP demonstrated excellent performance in simulations.

Fetal nasal bone length and Down syndrome during the second trimester in a Chinese population.

OBJECTIVE: The purpose of the present study was to build a database of reference ranges of fetal nasal bone length (NBL) in a Chinese population. The accuracy rate of detecting Down syndrome was also analyzed using fetal NBL as a marker. METHODS: The control group of fetuses included 342 normal singleton pregnancies with no chromosomal or congenital anomalies. The present study was a cross-section study and the control group was used to construct percentile values of NBL from 13 to 29 gestational weeks of age. Two-dimensional ultrasonography was used for the nasal bone studies. Measurements of NBL were collected and each fetus contributed a single value to the reference sample. During the study period, 14 fetuses with Down syndrome were examined. Measurement of fetal NBL was made during amniocentesis, with gestational age ranging from 13 to 19 weeks. RESULTS: From 342 normal fetuses with gestational age ranging from 13 to 29 weeks, reference ranges of NBL were constructed. The reference ranges were constructed from the 100(1 - p)% reference range: Y +/- Zp x square root sigma 2, where Y = 25 - exp(3.58 - 0.044 x t + 0.0006 x t2), with Y being the fitted mean of regression model and t being gestational age (weeks). Using fetal NBL, the regression model was Pr(Down syndrome) = exp(W)/ [1 + exp(W)], where W = 0.62-4.80 x NBL (multiples of the median) in predicting Down syndrome. Fetal NBL was found to have a sensitivity and specificity of 0.78 and 0.78, respectively, in predicting Down syndrome in the second trimester of pregnancy. CONCLUSIONS: Fetal NBL measurement can provide a simple and useful algorithm to predict Down syndrome during the second trimester of pregnancy.

Ductus venosus blood flow resistance and congenital heart defects in the second trimester.

PURPOSE: To study the association between fetal cardiac defects and the presence of abnormal blood flow resistance of the ductus venosus during the second trimester of pregnancy. METHODS: This retrospective case-control study included 72 pregnancies with fetal cardiac anomalies and 267 normal pregnancies. In fetuses with cardiac anomalies, Doppler velocimetry resistances of the ductus venosus were serially determined prior to birth. The Doppler velocimetry resistances obtained from fetuses with cardiac anomalies were in turn compared with median values derived from 267 normal pregnancies to compensate for biometric bias due to gestational age. RESULTS: Among the 72 pregnancies with fetal cardiac anomalies, 26 fetuses showed isolated congenital heart disease (CHD) without nonimmune fetal hydrops (NIFH) (group A), 10 fetuses showed isolated CHD with severe heart defects, including atrioventricular valve insufficiency and consecutive cardiogenic NIHF (group B), and 36 fetuses showed chromosomal abnormalities, nonchromosomal extracardiac malformations, noncardiogenic NIHF, and fetal growth restriction summarized as nonisolated CHD (group C). Based on the pulsatility index for the vein of the ductus venosus, the area under the receiver operating characteristic (ROC) curves was 0.71, 0.73, and 0.86 for groups A, B, and C, respectively. CONCLUSION: In the 36 fetuses from group C, increased pulsatility index for vein of the ductus venosus (DVPIV) yielded a significant area under the ROC curve (0.86) with a sensitivity of 0.78 and a specificity of 0.78. Increased DVPIVs during the second trimester of pregnancy are highly correlated with fetal cardiac anomalies associated with chromosomal and extracardiac anomalies.

Combination of fetal Doppler velocimetric resistance values predict acidemic growth-restricted neonates.

OBJECTIVE: This study was undertaken to determine the efficacy of combination Doppler velocimetric resistance values of the umbilical artery and ductus venosus in predicting growth-restricted neonates with acidemia. METHODS: This retrospective case-control study included 61 gravidas complicated by intrauterine growth restriction with acidemia and 65 control pregnancies. The Doppler velocimetric resistance values obtained from the growth-restricted and control fetuses were in turn compared with the median values derived from another 192 normal pregnancies to adjust the biometric bias due to gestational age. RESULTS: Based on the pulsatility index of the umbilical artery and pulsatility index for the vein of the ductus venosus, the areas under the receiver operating characteristic curves were 0.7992 and 0.6749, respectively, for predicting growth-restricted neonates with acidemia. With a combination of the pulsatility indices of the umbilical artery and the pulsatility indices for the vein of the ductus venosus, the predictive accuracy of the growth-restricted neonates with acidemia increased, with sensitivity of 0.79 and specificity of 0.79 and an area under the receiver operating characteristic curve of 0.8441. CONCLUSIONS: Compared with single-vessel assessment, combining the pulsatility indices of the umbilical artery and the pulsatility indices for the vein of the ductus venosus provides the greatest accuracy in predicting growth-restricted neonates with acidemia.

Comparison of two interbody fusion cages for posterior lumbar interbody fusion in a cadaveric model.

Although the Brantigan cage and Bagby and Kuslich (BAK) cage have different geometrical characteristics, clinical observations suggest that they are equally effective in restoring disc height and stability across the involved spinal segments. This study was designed to compare their performance as posterior lumbar interbody fusion devices at two levels in fresh ligamentous cadaver lumbar spines (L2-S1). After mounting in a testing frame, the three-dimensional load-displacement behaviour of each vertebra was quantified using the Selspot II Motion Measurement System for; the intact state, posterior decompression, and stabilisation, using a pair of Brantigan or BAK cages across L4-S1, additional stabilisation using Isola spinal instrumentation across L4-S1, and cyclic loading in flexion/extension. In the "cage-only" state, the Brantigan cage did not restore the stability in right axial rotation, whereas the BAK cage not only restored stability in all six directions but also improved lateral bending. After implanting the posterior instrumentation, both groups exhibited similar stability, and cyclic loading did not alter this. Although the Brantigan cage appears less effective than the BAK cage, implantation of posterior instrumentation significantly improves stability and reduces the differences between them. This underscores the need to use posterior instrumentation to achieve a higher initial stability.

Long-term efficacy and safety of very-low-dose amiodarone treatment for the maintenance of sinus rhythm in patients with chronic atrial fibrillation after successful direct-current cardioversion.

BACKGROUND: Long-term maintenance of sinus rhythm after successful conversion of chronic atrial fibrillation (CAF), often ameliorates patients' symptoms, reduces the risk of ischemic stroke and improves cardiovascular hemodynamics. This prospective study aims to evaluate the long-term efficacy and safety of very low-dose amiodarone (100 mg daily) for the maintenance of sinus rhythm after successful direct-current (DC) cardioversion in patients with CAF and rheumatic heart disease (RHD) post intervention. METHODS: This study was a randomized prospective trial. One day after successful DC cardioversion (remained normal sinus rhythm) in patients with CAF and RHD post intervention for more than six months and adequate anticoagulation, all were randomly administered either amiodarone 200 mg daily in group A or amiodarone 100 mg daily in group B. RESULTS: A total of 76 patients (40 men and 36 women) were examined from February 1998 to December 1999. The mean age of the patients was (66 +/- 10) years, and the mean follow-up was (67 +/- 8) months (range 61 to 84 months). Actuarial rates of the maintenance of sinus rhythm were similar in the two groups after 5 years of follow-up. Four patients (11%) in group A but none in group B experienced significant adverse effects that necessitated withdrawal of amiodarone. No death occurred during the study period. CONCLUSION: A very low dose of amiodarone results in adequate long-term efficacy and is safe for maintaining sinus rhythm in patients with CAF and RHD post intervention after successful DC cardioversion.

Posterior instrumentation reduces differences in spine stability as a result of different cage orientations: an in vitro study.

STUDY DESIGN: A multisegmental cadaveric spine model was used to quantify the load-displacement behavior of intact spine specimens, specimens injured and stabilized using Bagby and Kuslich (BAK) cages as lumbar interbody fusion devices with or without posterior instrumentation across two levels. OBJECTIVES: To compare the stabilities imparted by the cages placed using an oblique and conventional posterior approaches and to determine the effects of supplementary posterior instrumentation. SUMMARY OF BACKGROUND DATA: The BAK cage as posterior lumbar interbody fusion (PLIF) has been used to restore disc height, reduce morbidity, provide immediate stability to the patients, and enhance fusion rates. The obliquely inserted BAK cage has the advantages of reducing exposure and precise implantation. The biomechanical efficacy of this procedure is sparse, especially in comparison to the PLIF with and without posterior instrumentation. METHODS: Nine fresh human ligamentous spines (L2-S1) were affixed within a testing frame for determining their load-displacement behaviors. Load testing in clinically relevant modes was performed sequentially for the intact and the following procedures across the L4-S1 segment: posterior destabilization, stabilization using two parallel BAK cages (CBAK group) or one oblique BAK cage (OBAK group), further stabilization with posterior instrumentation, and finally cyclic loading in flexion-extension. Spatial positions of the LEDs attached to vertebral bodies were recorded using a three-dimensional motion measurement system. RESULTS: When used alone to restore stability, the orientation of the cage affected the outcome. In flexion OBAK orientation and in extension CBAK orientation provided better stability (decrease in motion with respect to intact case), compared with the other orientation. In lateral bending, CBAK orientation was found to be better than OBAK. In axial mode, CBAK orientation was effective in both directions while OBAK was effective only in right axial rotation. With the supplementary posterior fixation, the differences in stability resulting from the orientations were not noticeable at all, both before and after cyclic tests. CONCLUSIONS: Owing to the differences in the surgical approach and the amount of dissection, the stability for the cages when used alone as a function of cage orientation was different. These subtle differences were reduced by the use of posterior fixation device, underscoring the importance of using instrumentation when cages are used as PLIFs. However, the oblique insertion may be more favorable since it requires less exposure, enables precise implantation, and is less expensive, especially when used with supplementary instrumentation.

Nuchal translucence incorporated into a one-stage multifactorial screening model for Down syndrome prediction at second-trimester pregnancy.

The aim of this study was to achieve one-stage screening for trisomy 21 using a combination of nuchal translucency (NuT) measurement and maternal serum alpha-fetoprotein (AFP) and free beta-human chorionic gonadotrophin (hCG) biochemistry levels in the second trimester among a high-risk study population. From January 1998 to June 2001, 45 cases of trisomy 21 were prenatally found and confirmed in the hospital-based cytogenetic diagnosis laboratory. A total of 867 normal singleton pregnancies were enrolled as controls from the antenatal care clinics in the hospital. All study and control subjects between 13 weeks and 18 weeks of gestation with a mean age of 15.2 +/- 1.3 weeks underwent one-stage nuchal translucence measurements and maternal serum biochemical screening for Down syndrome. The final logistic model contained beta-hCG (multiples of the gestational median or MoM), maternal age (matA), nuchal translucence (NuT MoM) and AFP (MoM) as covariates. Also, the estimated coefficients of the regression were highly significant. This model provided the estimated probability of Down syndrome as follows: Pr (Down syndrome) = exp (Z)/ [1 + exp (Z)], where Z = -11.18 + 0.64 x (beta-hCG MoM) + 0.25 x matA + 1.32 x NuT MoM -2.23 x AFP MoM. The logistic regression with estimated coefficients was installed in a Palm digital assistant (PDA) equipped with Excel (Microsoft). The risk probability of Down syndrome could be readily calculated after inputting data for all four predictor variables.