SEARCH · PubMed Health

Results for “Multivariate response regression”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 793 records · Page 44Linked to original sources

PubMed2005

Low back pain and pelvic pain during pregnancy: prevalence and risk factors.

STUDY DESIGN: Cross-sectional study. Women giving birth at one of two hospitals of northern Sweden from 1 January 2002 until 30 April 2002 were invited to fill in a questionnaire on their obstetric and gynecological history, actual pregnancy, and delivery. OBJECTIVE: The aim of this study was to investigate prevalence and risk factors for low back pain and pelvic pain (LBPP) during pregnancy. SUMMARY OF BACKGROUND DATA: Although low back pain and pelvic pain during pregnancy is a most common complication of pregnancy, its etiology is unknown and the pathophysiology is poorly understood. METHODS: The sample was analyzed by calculating the prevalence of LBPP during pregnancy. Univariate and multivariate logistic regression was performed to calculate odds ratio (OR) and its 95% confidence intervals (CI) where applicable. Parametric and nonparametric testing was used to establish differences between groups. RESULTS: The response rate was 83.2% (N = 891). The prevalence of LBPP during pregnancy was 72%. Most cases reported both anterior and posterior pain. Increasing parity, history of hypermobility, and reported periods of amenorrhea were risk factors for LBPP. Women with LBPP had significantly higher prepregnancy weight, end-pregnancy weight, and prepregnancy and end-pregnancy body mass index. Age at menarche and use of oral contraceptives were not associated with LBPP. Nonrespondents were of the same age and parity as respondents. CONCLUSIONS: A majority of pregnant women report LBPP. Parity, LBPP during a previous pregnancy, body mass index, a history of hypermobility, and amenorrhea are factors influencing the risk of developing LBPP during pregnancy.

Adult↗

PubMed2002

Iron plus folate is more effective than iron alone in the treatment of iron deficiency anaemia in pregnancy: a randomised, double blind clinical trial.

OBJECTIVE: To evaluate whether folate supplementation to iron is able to accelerate solving of iron deficiency anaemia in pregnancy. DESIGN: Multicentre, double blind, randomised clinical trial. SETTING: Nine hospital gynaecologic units located in Mexico. POPULATION: Three hundred seventy-one women with iron deficiency anaemia between 14 and 27 weeks of pregnancy. METHODS: Random allocation of the study population to receive 80 mg iron proteinsuccinylate, with or without 0.370 mg folinic acid daily for 60 days. MAIN OUTCOME MEASURE: Haemoglobin concentration increase. RESULTS: Combined iron and folate therapy showed a better therapeutic response: the increase in haemoglobin levels from baseline was 1.42 (0.14) g/dL for women treated with both compounds vs 0.80 (0.125) g/dL for those given iron only (P < 0.001). A multivariable regression analysis showed that this effect was independent of basal levels of blood iron, ferritine and serum folate and was more evident in women with more severe anaemia. In the 64 women belonging to the subgroup defined by the per-protocol (PP) population and the lowest quartile of baseline haemoglobin values (mean 8.96, range 5.9-9.8 g/dL), the increase at day 60 was estimated 2.3 (0.53) g/dL for the combined therapy vs 0.5 (0.5) g/dL for iron only (P = 0.07). No significant differences in tolerability were observed between the two groups. CONCLUSION: Folate supplementation is recommendedin pregnant women with iron deficiency anaemia irrespective of the serum levels of folate.

Adult↗

PubMedDate not supplied

Once-daily use of ofloxacin for prophylaxis in breast cancer surgery.

The 150 consecutive patients who were hospitalized for breast cancer at our department between September 1992 and November 1995 were enrolled in this open study after having given their informed consent. Patients were assigned randomly to receive ofloxacin in daily doses of 200 mg to be taken in a single dose or a total dose of 600 mg divided into three doses postoperatively for 5 days. Ten patients (8 found to be without malignancies) were excluded from evaluation. Wound infections developed in 8 (12%) of the 69 patients in the 200-mg group and 12 (17%) of the 71 patients in the 600-mg group. Postoperative wound care lasted a median of 19 days (25th and 75th percentiles, 15 and 29 days) for patients given 200 mg and 16 days (13 and 25 days) for those given 600 mg; the difference was not statistically significant (Wilcoxon's U test). Signs or symptoms suggesting ofloxacin toxicity were not observed, and several significant differences were found in laboratory test results between the two groups both before and after treatment. Abnormal changes after treatment were found in many individuals, but the rate of occurrence was similar in the two groups (U test). When ofloxacin is used for prophylaxis after breast surgery, we recommend a once-daily administration of 200 mg orally for financial reasons and increased patient compliance.

Adult↗

PubMed2002

[Acute hepatitis C].

OBJECTIVE: The aim of the study was both to evaluate the natural outcome of acute hepatitis C (AHC), in this factors influencing chronicity of HCV, and to assess results of antiviral therapy in acute phase of disease. PATIENTS AND METHODS: Seventy-seven pts with diagnosis of AHC (all HCVRNA-positive, in this 44 anti-HCV-positive at entry) were seen. Sixty-four of them (F/M: 33/31; mean age: 45.4y +/- 16.0) were non-treated (NT pts) with IFN during 6-months follow-up and thirteen patients (F/M: 5/8; mean age: 36.6ys +/- 11.9) were treated (T pts) with IFN. Antiviral therapy was started within 2 to 18 (median 10) weeks after the onset of AHC including seven pts with IFN alpha-2b at 5MU thrice weekly (TIW) and one pt with IFN-alpha-2a at 6MU TIW for 24 weeks, three pts with combined (Rebetron) therapy according to HCV genotype (1F/3a for 24 weeks and 2M/1b for 48 weeks) and two pts with PEG-Intron for one month followed by Intron at 3MU TIW for 20 weeks. RESULTS: 64.1% of NT pts developed chronic hepatitis. In multivariate logistic regression analysis age > 40y, nonicteric course and medical procedures as route of infection were independently and significantly associated with chronicity. Ten of the thirteen (77%) treated pts presented sustained response (SR) at the end of follow-up. Only one seronegative pt no responded to the therapy. The others 12 pts (all seropositive) presented rapid normalisation of ALT levels. However, 3 of them developed breakthrough between 12 and 20 week of therapy and ribavirin was added with beneficial effect. At the end of treatment point, all seropositive patients showed biochemical and virological response but two (with breakthrough history) of them relapsed. CONCLUSIONS: Seropositive, nonicteric patients with acute hepatitis C should be treated as soon as possible and pegylated-IFN for 24 weeks seems to be currently the best choice. Combination therapy with PEG and ribavirin could be proposed to the patients who failed to monotherapy. The beneficial effect of AHC therapy is indicative for necessity of creating conditions for diagnosed AHC more frequent than hitherto.

Acute Disease↗

PubMedDate not supplied

International survey of peritoneal dialysis training programs.

OBJECTIVE: To survey nurses around the world about current practices for peritoneal dialysis (PD) home training programs. DESIGN: Random sampling of nurses to complete a written survey from the International Society for Peritoneal Dialysis Nursing Liaison Committee. SETTINGS: United States, Canada, South America (Brazil, Columbia), The Netherlands, Hong Kong. METHODS: Surveys and responses were sent by fax whenever possible, or by regular mail, or hand carried, or conducted by telephone. Results were stratified by geographic areas as well as by cumulative responses and were expressed as medians with ranges. Kruskal-Wallis was used to evaluate differences in responses. Associations between variables were tested with Pearson correlation. Univariate regression analysis was used to evaluate the impact of variables on peritonitis rates. Variables with p < 0.10 were included in a multivariate analysis. RESULTS: A total of 317 nurses responded: 88 in the United States, 46 in Canada, 58 in South America, 58 in Hong Kong, and 67 in The Netherlands. This represented 37% of all surveys distributed. Respondents had a median of 12 years' experience in nephrology (range 1-35 years), but only 31% had a formal background in adult education. Nearly half received their guidance to patient training from a nurse colleague, 11% were guided by a corporate colleague, and 8% were simply self-taught. Clinics responding had a median of 30 PD patients (range 1-400) and reported they trained a median of 8 patients per year (range 0-86). Reported peritonitis rates were a median 0.46 per year or 1 episode every 26 months. Peritonitis rates, however, were not known by 53% of respondents. Total training time per patient had a very wide range of hours, from 6 to 96. There was no correlation between training time and peritonitis rates among the study respondents (p = 0.38), nor with any other variables. CONCLUSIONS: There is wide variation in practices for PD patient training programs within countries and around the world. Training time did not appear to be related to peritonitis rates. Randomized trials of training practices are needed to determine which approaches produce the best outcomes for patients.

Hemodialysis, Home↗

PubMed1988

Low-density lipoprotein subclass patterns and risk of myocardial infarction.

The association of low-density lipoprotein (LDL) subclass patterns with coronary heart disease was investigated in a case-control study of nonfatal myocardial infarction. Subclasses of LDL were analyzed by gradient gel electrophoresis of plasma samples from 109 cases and 121 controls. The LDL subclass pattern characterized by a preponderance of small, dense LDL particles was significantly associated with a threefold increased risk of myocardial infarction, independent of age, sex, and relative weight. Plasma levels of high-density lipoprotein cholesterol were decreased, and levels of triglyceride, very low-density lipoproteins, and intermediate-density lipoproteins were increased in subjects with this LDL subclass pattern. Multivariate logistic regression analyses showed that both high-density lipoprotein cholesterol and triglyceride levels contributed to the risk associated with the small, dense LDL subclass pattern. Thus, the metabolic trait responsible for this LDL subclass pattern results in a set of interrelated lipoprotein changes that lead to increased risk of coronary heart disease.

Aged↗

PubMed2006

Antimüllerian hormone predicts ovarian responsiveness, but not embryo quality or pregnancy, after in vitro fertilization or intracyoplasmic sperm injection.

Antimüllerian hormone (AMH) and other markers of ovarian reserve were assessed to determine their predictive value with respect to treatment outcome. In a multivariate regression analysis, AMH was found to be predictive of the number of oocytes and the number of embryos, but not of embryo quality or the chance of a pregnancy, after IVF/ICSI.

Adult↗

PubMed2005

Association between quality of life scores and short-term outcome after surgery for cancer of the oesophagus or gastric cardia.

BACKGROUND: Evidence suggests that baseline quality of life (QOL) scores are independently prognostic for survival in patients with cancer, but the role of QOL data in predicting short-term outcome after surgery is uncertain. This study assessed the association between QOL scores and short-term outcomes after surgery for oesophageal and gastric cancer. METHODS: Consecutive patients selected for oesophagectomy or total gastrectomy between November 2000 and May 2003 completed the European Organization for Research and Treatment of Cancer's quality of life questionnaire, QLQ-C30. Multivariable regression models, adjusting for known clinical risk factors, were used to investigate relationships between QOL scores, major morbidity, hospital stay and survival status at 6 months. RESULTS: Of 130 patients, 121 completed the questionnaire (response rate 93.1 per cent). There were 29 major complications (24.0 per cent) and 22 patients (18.2 per cent) died within 6 months of operation. QOL scores were not associated with major morbidity but were significantly related to survival status at 6 months after adjusting for known clinical risk factors. A worse fatigue score of 10 points (scale 0-100) corresponded to an increase in the odds of death within 6 months of surgery of 37.4 (95 per cent confidence interval (c.i.) 12.4 to 67.8) per cent (P = 0.002). Pretreatment social function scores were moderately associated with hospital stay (P = 0.021); a reduction in social function by 10 points corresponded to an increase in hospital stay of 0.93 (95 per cent c.i. 0.12 to 1.74) days. CONCLUSION: QOL scores supplement standard staging procedures for oesophageal and gastric cancer by providing prognostic information, but they do not contribute to perioperative risk assessment.

Adult↗

PubMed1999

A comparison of exposure groups in the EuroSIDA study: starting highly active antiretroviral therapy (HAART), response to HAART, and survival.

BACKGROUND: Concerns have been raised that intravenous drug users may be less likely to start highly active antiretroviral therapy (HAART) and that adherence to therapy may be poor among this group of patients. Given the decreased mortality and incidence of AIDS-defining illnesses among patients with HIV who start HAART, this may lead to a poorer prognosis among intravenous drug users. PURPOSE: To compare homosexual men, intravenous drug users, and heterosexuals in EuroSIDA, a prospective European cohort of 7331 patients with HIV in terms of starting a HAART treatment regimen, immunologic and virologic response to therapy, and survival. METHODS: 6645 patients were included in this analysis. Logistic regression and Cox proportional hazards models were used to investigate the factors associated with use of HAART regimens and survival following recruitment to the EuroSIDA study. RESULTS: In a multivariate logistic regression model, intravenous drug users were significantly less likely to be receiving HAART at recruitment to EuroSIDA (odds ratio [OR], 0.48; 95% confidence interval [CI], 0.37-0.62; p<.0001) when compared with homosexual men. Similarly, during follow-up, intravenous drug users were at a 27% reduced risk of starting HAART, after adjustment for other factors related to starting HAART (relative hazard [RH], 0.73; 95% CI, 0.64-0.82; p<.0001). There were no differences between heterosexual and homosexual patients, and similar results were found within regions of Europe (South, Central and Northern). Among those patients who started HAART, there were no significant differences between exposure groups in CD4 lymphocyte count response to HAART or virologic response to HAART. After adjustment for factors related to survival, intravenous drug users were at a small, but nonsignificant increased risk of death compared with homosexuals (RH 1.16; 95% CI, 0.99-1.38; p = .074). CONCLUSIONS: Intravenous drug users were significantly less likely to start HAART, but among those who did, response to therapy was similar to that of other exposure groups. There were no differences in risk of death. If intravenous drug users continue to use HAART less commonly than other exposure groups, it may result in a poorer prognosis, a different spectrum of AIDS-defining illnesses, and differential long-term clinical needs.

Adult↗

PubMed2002

Genetic polymorphisms of the interleukin-4 receptor alpha gene are associated with an increasing risk and a poor prognosis of sporadic renal cell carcinoma in a Japanese population.

PURPOSE: It has been suggested that the immune system of the host may be capable of modulating the clinical course of renal cell carcinoma (RCC) patients. In fact, the amount of Th2 cytokines such as interleukin (IL)-4 and IL-10 in the serum of patients has been found to be an important predictor of poor prognosis. Recently, it was reported that genetic polymorphisms of the IL-4 receptor alpha (IL-4Ralpha) gene affect the strength of signaling through the receptor. In addition, these same polymorphisms were found to be associated with an increased risk of atopy by causing Th2-dominated responses of the host. The significance of the polymorphisms on the incidence and prognosis in sporadic RCC patients were examined to clarify the role of IL-4 as well as that of the Th1/Th2 immune system in this disease. EXPERIMENTAL DESIGN: A case-control study was performed with 143 sporadic RCCs in a Japanese population and 205 Japanese controls. Logistic regression models were also used to assess the genetic effects on prognosis. RESULTS: The frequencies of variant alleles that enhance signaling of IL-4 were significantly related to an increased risk of RCC. Furthermore, multivariate regression analysis showed that the genotype of the IL-4R gene was an independent prognostic factor for cause-specific survival (P = 0.018) together with M classification (P = 0.0002) and histopathological grade (P = 0.044). CONCLUSIONS: The present findings show that the preferential Th2-type response to tumors was associated with a poorer prognosis and suggest that polymorphisms of the IL-4Ralpha gene may serve as useful genetic markers for assessing the risk of the development and progression of RCC.

Adult↗

PubMed2002

Exact multivariate tests for brain imaging data.

In positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) data sets, the number of variables is larger than the number of observations. This fact makes application of multivariate linear model analysis difficult, except if a reduction of the data matrix dimension is performed prior to the analysis. The reduced data set, however, will in general not be normally distributed and therefore, the usual multivariate tests will not be necessarily applicable. This problem has not been adequately discussed in the literature concerning multivariate linear analysis of brain imaging data. No theoretical foundation has been given to support that the null distributions of the tests are as claimed. Our study addresses this issue by introducing a method of constructing test statistics that follow the same distributions as when the data matrix is normally distributed. The method is based on the invariance of certain tests over a large class of distributions of the data matrix. This implies that the method is very general and can be applied for different reductions of the data matrix. As an illustration we apply a test statistic constructed by the method now presented to test a multivariate hypothesis on a PET data set. The test rejects the null hypothesis of no significant differences in measured brain activity between two conditions. The effect responsible for the rejection of the hypothesis is characterized using canonical variate analysis (CVA) and compared with the result obtained by using univariate regression analysis for each voxel and statistical inference based on size of activations. The results obtained from CVA and the univariate method are similar.

Algorithms↗

PubMed2002

A hospital-level analysis of the work environment and workforce health indicators for registered nurses in Ontario's acute-care hospitals.

The purpose of this study was to explore the relationship between hospital-level indicators of the work environment and aggregated indicators of health and well-being amongst registered nurses working in acute-care hospitals in Ontario, Canada. This ecological analysis used data from a self-reported survey instrument randomly allocated to nurses using a stratified sampling approach. Multivariable linear regression models were used to examine hospital-level associations for burnout, musculoskeletal pain, self-rated general health, and absence due to illness. The unit of analysis was the hospital (n = 160), with individual nurse responses (n = 6,609) aggregated within hospitals. After controlling for basic differences in nurse workforces, including mean age and education, higher (better) work-environment scores were found to be generally associated with higher health-indicator scores, while a larger proportion of full-time than part-time nurses was found to be associated with lower (poorer) health scores. This study may provide direction for policy-makers in coping with the recruitment and retention of nursing staff in light of the current nursing shortage.

Health Facility Environment↗

PubMed2001

Umbilical cord serum ionized magnesium level and total pediatric mortality.

OBJECTIVE: To estimate whether higher magnesium levels in umbilical cord blood at delivery are associated with increased total pediatric (fetal + neonatal + postneonatal) mortality. METHODS: During the Magnesium and Neurologic Endpoints Trial, in addition to randomizing mothers having preterm labor into arms containing magnesium sulfate, other tocolytic agents, or saline controls, we obtained biologic specimens at delivery, including umbilical cord venous blood on which was determined the serum ionized magnesium level using the AVL 988-4 analyzer (Graz, Austria). Laboratory results were then matched with the pediatric mortalities. The study power was based on the anticipated reductions in neonatal intraventricular hemorrhage related to magnesium usage from 18.9% to 4.4%. For alpha =.05, 1-beta (power)=80%, two tailed, the total number of infants needed would be 140. RESULTS: Of 149 mothers who gave permission for randomization, ionized magnesium levels were available for 82 children. Seven deaths occurred (one immediately before delivery, three as neonates, and three in the postneonatal period). The median level of ionized magnesium among the seven dead children was 0.76 mmol/L; among the 75 survivors, the median level of ionized magnesium was 0.55 mmol/L (Mann-Whitney U test, P =.03). Using multivariable logistic regression analysis, the association remained statistically significant when controlling for possible confounding factors (adjusted odds ratio 7.7, 95% confidence interval 1.2, 47.6, P =.03). CONCLUSION: These findings of a dose response between serum ionized magnesium and deaths in children increase our concern about the improper use of tocolytic magnesium.

Adult↗

PubMed2004

Dental treatment need among 20 to 25-year-old Swedes: discrepancy between subjective and objective need.

Our aim was to analyze variables from a questionnaire sent to 20 to 25-year-old Swedes to determine how they perceive their oral treatment need, and to determine which variables affect this perception. The questionnaire was sent to 650 individuals randomly selected from the database of the National Social Insurance Board of Sweden. The response rate was 78%. Another questionnaire was sent to the dentists of these young adults in order to collect clinical information. The response rate was 66%. The respondent's answer to the question 'How do you rate your dental treatment need today?' was dichotomized and used as a dependent variable in a multivariate logistic regression model. Each increase in number of decayed-filled teeth led to a 13% increased treatment need, bad oral hygiene a 2.24-fold increase, and no periodontal disease an 80% reduction in treatment need. A higher education beyond comprehensive school increased the perceived treatment need 7.16 times; a poorer dental health than one's contemporaries led to a 14.47-fold increase. When dentist and patient assessments were combined, variables related to the patients' self-assessments were the only significant contributors to the statistical model. A lack of concordance between patients' and dentists' assessments of treatment need was found which highlighted the differences between patients' and dentists' views on treatment need. This study shows the importance of communication between dentist and patient.

Adult↗

PubMed2001

Injury proneness and personality.

The aim of this research was to investigate some personality factors among groups of 43 physically injured inpatients and 43 non-injured hospital-based controls. The participants completed the Eysenck Personality Questionnaire (EPQ) and the Coping Styles Questionnaire (CSQ). Logistic regression was used to compare the two groups on six psychological risk factors. The univariate regression models suggested three possible risk factors: extraversion, sensitization, and avoidance coping style. The multivariate regression model supported only extraversion and sensitization of emotion. Next, patients in the experimental group were questioned about whether they had considered preventive measures before the accident and whether they felt responsible for their injuries. Correlation analysis showed that introverted subjects felt more responsible for the sustained injuries than their extraverted counterparts. Sensitizers and subjects who scored high on psychoticism, neuroticism, and emotional coping had not considered preventive measures as often as others. Finally, the principal component analysis of risk factors was used to extract two correlates of injury-prone behaviour: extraversion and sensitized avoidance. It was concluded that psychological factors play an important role in predicting injury that is significant enough to require inpatient treatment. Two potential mechanisms of psychological impact have been suggested, notably distraction in extraverted subjects and overestimation in sensitizing avoiders.

Accident Prevention↗

PubMed2026

Multi-omics dynamic profiling reveals predictive biomarkers for first-line immunochemotherapy in extensive-stage small-cell lung cancer.

BACKGROUND: Extensive-stage small-cell lung cancer (ES-SCLC) is associated with a poor prognosis. Although first-line immunochemotherapy improves clinical outcomes, robust prognostic biomarkers for this treatment modality remain unavailable. The aim of this study was to identify non-invasive, easily accessible, and dynamically monitored biomarkers of ES-SCLC by machine learning integrating serum metabolomics, lipidomics, and proteomics at multiple time points. METHODS: A total of 816 serum samples were collected from ES-SCLC patients receiving first-line immunotherapy combined with chemotherapy or first-line chemotherapy for metabolomics, lipidomics, and proteomics analysis. The immunochemotherapy cohort was randomly divided into training and validation subsets at a 6:4 ratio. Biomarkers were identified using machine learning algorithms, and their prognostic significance was evaluated through receiver operating characteristic (ROC) analysis, Kaplan–Meier survival analysis, and multivariate Cox regression. Potential metabolic pathways and mechanisms were further explored via integrated multi-omic analysis. RESULTS: The immunochemotherapy exhibited a prolonged median progression-free survival (PFS) and higher objective response rate (ORR) compared to the chemotherapy group. A total of 5 serum metabolites (uric acid, L-aspartate-semialdehyde, dimethisterone, xanthine, L-cysteine), 6 lipids (Cer d18:1/26:0, Cer d18:2/25:0, SM d18:1/20:1, SM d17:1/25:1, DG O-18:1_16:0, PS 18:0_24:0), and 3 proteins (ACIN1, ACSL4, PHGDH) were identified and constructed into independent prognostic models. Among patients receiving immunochemotherapy, those categorized as low-risk based on the model demonstrated significantly longer PFS compared with those in the high-risk group. These prognostic signatures also retained predictive value in patients who underwent second-line treatment with anlotinib plus immunochemotherapy. Integrated analysis revealed that glycine, serine, and threonine metabolism was the commonly enriched pathway across all three omics layers. Notably, PHGDH (protein), L-aspartate-semialdehyde and L-cysteine (metabolites), and PS (18:0_24:0) (lipid), key elements in this pathway, were all incorporated in the predictive model. In addition, models of the composition of these substances after one cycle of treatment can still predict the prognosis of patients. CONCLUSION: In this study, we constructed and validated a set of non-invasive, dynamically monitorable prognostic models (containing 5 metabolites, 6 lipids, and 3 proteins) using machine learning by integrating multiple time point data from the serum metabolome, lipid panel, and proteome to accurately distinguish the prognostic risk of patients with ES-SCLC receiving immunochemotherapy. PFS was significantly prolonged in patients in the low-risk group, and this model remains predictive in the subsequent second-line treatment with anlotinib in combination with immunochemotherapy. Glycine-serine-threonine metabolic pathway may be the key mechanism, of which PHGDH, L-aspartate semialdehyde, L-cysteine and PS (18:0_24:0) are the core predictors. This study provides the first multi-omics dynamic prognostic tool for ES-SCLC immunochemotherapy and reveals potential therapeutic targets.

Humans↗

PubMed2004

Infantile hepatic hemangiomas: clinical and imaging findings and their correlation with therapy.

OBJECTIVE: This study was undertaken to determine different imaging patterns in infantile hepatic hemangiomas and to explore the relationship between clinical presentations, imaging findings, and response to therapy. MATERIALS AND METHODS: The imaging studies and clinical records of all patients with infantile hepatic hemangiomas from two tertiary children's hospitals were reviewed. Univariate and multivariate stepwise logistic regression techniques were used to determine whether clinical presentation and imaging variables differentiated the type of treatment required. RESULTS: Typical hemangiomas appeared as focal or multifocal T2-hyperintense spheres with centripetal contrast enhancement and dilated feeding and draining vessels. Three atypical patterns included focal mass lesions with central varix with or without direct shunts, focal mass with central necrosis or thrombosis, and massive hemangiomatous involvement of the liver with abdominal vascular compression. In general, patients with focal lesions without high flow needed no treatment, and those with central varix and direct shunts developed severe high-output cardiac failure that responded quickly to embolization. The pattern of massive replacement of liver was associated with hypothyroidism, abdominal compartment syndrome, and a high mortality rate. Multivariate analysis of 55 patients indicated that congestive heart failure was the only independent predictor of treatment (p = 0.005). The presence of a shunt was the only independent factor associated with embolization or surgery (p = 0.002). CONCLUSION: Although the imaging features of infantile hepatic hemangiomas vary to some extent, MRI features are typical in most patients and certain imaging findings are predictive of the clinical course. MRI is the technique of choice in diagnosing infantile hepatic masses.

Chi-Square Distribution↗

PubMed2005

A comprehensive portrait of teleradiology in radiology practices: results from the American College of Radiology's 1999 Survey.

OBJECTIVE: This article presents a comprehensive portrait of the characteristics of teleradiology systems of radiology practices as of 1999. Our purposes are to help profile a rapidly evolving area of radiology that has been underexamined to date and to provide a baseline with which future findings can be compared. MATERIALS AND METHODS: In 1999, the American College of Radiology surveyed 970 practices by mail. A response rate of 66% was achieved. Responses were weighted to represent all radiology practices in the United States. Data from nine questions specifically designed to profile the use of teleradiology were analyzed using descriptive statistical methods and multivariate regression analyses. RESULTS: Seventy-one percent of multiradiologist practices had teleradiology systems in place, using them to interpret 5% of their studies. For solo practices, corresponding statistics were 30% and 14%. Ninety-two percent of multiradiologist practices with teleradiology systems used them for preliminary on-call interpretation. Other major uses included consultation with other radiologists (20%) and primary interpretation of studies (18%). Ninety-five percent of multiradiologist practices with teleradiology systems used them to interpret CT, 84% used them for sonography, 69% for nuclear medicine, 47% for MRI, and 43% for conventional radiographs. CONCLUSION: Teleradiology had already become a fixture in most practices by 1999, though it was used for only a small fraction of image interpretations. Its widespread presence positioned teleradiology to become a key element of radiology practice nationwide.

Diagnostic Imaging↗