Ratio Cut-off Point Research Articles

The catheter to vein ratio and rates of symptomatic venous thromboembolism in patients with a peripherally inserted central catheter (PICC): A prospective cohort study

BackgroundPeripherally inserted central catheters (PICCs) are a common vascular access device used in clinical practice. Their use may be complicated by adverse events such as venous thromboembolism (VTE). The size of the vein used for PICC insertion and thus the catheter to vein ratio is thought to be a controllable factor in the reduction of VTE rates in patients who have a PICC. However, an optimal catheter to vein ratio for PICC insertion has not previously been investigated to inform clinical practice. ObjectivesTo determine the effect of the catheter to vein ratio (proportion of the vein measured at the insertion point taken up by the catheter) on rates of symptomatic VTE in patients with a PICC and identify the optimal ratio cut-off point to reduce rates of this adverse event. MethodAdult patients waiting for PICC insertion at a large metropolitan teaching hospital were recruited between May and December 2013. Vein diameter at the PICC insertion site was measured using ultrasound with in-built callipers. Participants were followed up at eight weeks to determine if they developed symptomatic VTE. ResultsData were available for 136 patients (50% cancer; 44% infection; 6% other indication for PICC). Mean age was 57 years with 54% males. There were four cases of confirmed symptomatic VTE (two involving the deep veins, one peripheral vein and one pulmonary embolism). Receiver operator characteristic (ROC) analysis determined that a 45% catheter to vein ratio was the ideal cut off point to maximise sensitivity and specificity (AUC 0.761; 95% CI 0.681–0.830). When a ratio of 46% or above was compared to one that was less than or equal to 45% using a log binomial generalised linear model it was found that participants with a catheter to vein ratio >45% were 13 times more likely to suffer VTE (relative risk 13, p=0.022; CI 1.445–122.788). ConclusionIt was found that a 45% catheter to vein ratio was the optimal cut off with high sensitivity and specificity to reduce the risk of VTE. However, further research is needed to confirm these results as although adequately powered; the number of cases of VTE was comparatively small, resulting in wide confidence intervals.

CSF biomarkers and neuropsychological profiles in patients with cerebral small-vessel disease.

Despite existing criteria, differential diagnosis of Vascular Dementia (VD) and Alzheimer's disease (AD) remains difficult. The aim of this study is to figure out cognitive and biomarker profiles that may help to distinguish between VD, AD and AD + Cerebral Small Vessel Disease (CSVD). We examined a cohort of patients with CSVD (n = 92). After stratification of cognitive impaired patients (n = 59) using the standard CSF beta-amyloid 42/40 ratio cut-off point of 0.975, we obtained two groups which differed with respect to several features: 32 patients with normal beta-amyloid 42/40 ratio (>0.975) showed markedly impaired blood-brain-barrier function as indicated by an elevated albumin ratio (median 8.35). They also differed in cognitive profiles when compared to 27 patients with AD typical beta-amyloid ratio and normal albumin ratio. We also enrolled an additional group of patients with AD (no significant CSVD on MRI, n = 27) which showed no impairment of the blood-brain-barrier. We showed a negative correlation between the albumin ratio and executive cognitive function (p = 0.016) and a negative correlation between memory function and typical AD markers like Tau (p = 0.004) and p181-Tau (p = 0.023) in our cohort. We suppose that the group of patients with normal beta-amyloid ratio represents VD while patients in the other groups represent AD+CSVD and pure AD. Our results support the idea that a dysfunction of the blood-brain-barrier might be contributing factor in the development of cognitive decline in CSVD as it seems to be of more importance than the severity of white matter lesions.

Comparison of Timed Urine Collection to Protein–Creatinine Ratio for the Diagnosis of Preeclampsia

INTRODUCTION: Timely and accurate diagnosis of preeclampsia helps avoid significant maternal and fetal morbidity and mortality. There is no widely accepted cutoff for diagnosis of preeclampsia when a urine protein-to-creatinine ratio is collected. Our primary objective was to determine optimal protein-to-creatinine ratio point for the diagnosis of preeclampsia. METHODS: We retrospectively identified pregnant patients evaluated for preeclampsia between 2001 and 2011 who had both 24-hour timed urine collection and protein-to-creatinine ratio collected within 30 hours. Using 300 mg urine protein as diagnostic for preeclampsia, protein-to-creatinine ratios were analyzed by testing individual cutoff points. A receiver operating characteristic curve was constructed to determine maximum sensitivity and specificity and the area under the curve. The optimal cutoff point was determined based on receiver operating characteristic curve results. RESULTS: One hundred eighty-eight patients met inclusion criteria and were analyzed. Mean age was 28.5 years (standard deviation 5.9). Demographics included 55.9% African American and 38.8% white. Maximum sensitivity (83.32%) and specificity (83.33%) was found at a protein-to-creatinine ratio cutoff point of 0.24. Using a protein-to-creatinine ratio of 0.24, area under the curve was 0.88 (95% confidence interval 0.82–0.93). By increasing the protein-to-creatinine ratio cutoff to 0.30, sensitivity decreases (75.53%) and specificity increases (91.67%) resulting in a 50% reduction in the false-positive rate when compared with our optimal cutoff (16.67–8.33%). CONCLUSION: Protein-to-creatinine ratio of greater than or equal to 0.24 optimizes sensitivity and specificity within our population. A protein-to-creatinine ratio of greater than or equal to 0.30 may serve as better “rule in” cutoff where no reflex timed urine is necessary. We suggest 0.24–0.30 as a range for immediate reflex timed urine protein collection.

The diagnostic role of (18)F-FDG PET for primary central nervous system lymphoma.

(18)F-FDG PET has become one of the most important methods for studying malignant lymphoma, but its diagnostic role for primary central nervous system lymphoma (PCNSL) has not been established. The aim of this study was to determine the appropriate cut-off values of FDG uptake and to investigate how corticosteroid administration influences PCNSL. We retrospectively reviewed 82 patients with contrast-enhanced brain tumors who underwent an FDG PET scan at onset, including 19 PCNSLs. FDG uptake of the lesion was assessed by the maximum standardized uptake value (SUVmax) and the ratio of tumor to normal contralateral cortex activity (T/N ratio). Receiver operating characteristic (ROC) curves were generated from the SUVmax and T/N ratios. To investigate the influence of corticosteroid application before a FDG PET scan, we evaluated the association between the FDG uptake of the lesion and the cumulative dose of corticosteroid administration on 13 PCNSL patients who had received steroid treatment before an FDG PET examination. The mean FDG SUVmax and T/N ratio of PCNSLs were 22.6 and 2.79, respectively, and these values were significantly higher than those of the other malignant brain tumors. ROC analysis indicated that the evaluation of FDG uptake using the T/N ratio was more reliable than the SUVmax with respect to the differential diagnosis. When PCNSL patients went without steroid application before FDG PET, the accuracy of the T/N ratio with a cut-off point of 2.0 was 91.1%, the sensitivity was 94.7%, and the specificity was 87.3%. Although there are no significant differences in the FDG T/N ratio for PCNSL patients with or without steroid treatment, a negative correlation was found between the T/N ratio and cumulative dose of corticosteroid before PET study (r = -0.71, p = 0.032). We concluded that the T/N ratio was superior to SUVmax for FDG uptake assessment as for distinguishing PCNSLs from other malignant brain tumors; the appropriate T/N ratio cut-off point was 2.0. In addition, FDG uptake could be influenced by cumulative doses of corticosteroid before a PET scan, and thus this fact should be taken into consideration when evaluating FDG PET for PCNSL diagnosis.

Neutrophil-lymphocyte ratio in patients with familial Mediterranean fever.

Blood neutrophil-to-lymphocyte (N/L) ratio is an indicator of the overall inflammatory status of the body, and an alteration in N/L ratio may be found in patients with familial Mediterranean fever (FMF). The aim of this study was to investigate the interrelationship between N/L ratio and FMF. One hundred and fifteen patients and controls were enrolled in the study. The cases in the study were categorized as FMF with attack, FMF with attack-free period, and controls. The neutrophil and lymphocyte counts were recorded, and the N/L ratio was calculated from these parameters. All patients were diagnosed according to Tel Hashomer criteria. A total of 79 FMF patients were included in the study and all subjects were receiving colchicine treatment at the time. The serum N/L ratios of active patients were significantly higher than those of attack-free FMF patients and controls (P < 0.001). The optimum N/L ratio cut-off point for active FMF was 2.63 with sensitivity, specificity, positive predictive value, and negative predictive value of 0.62 (0.41-0.80), 0.85 (0.72-0.93), 0.67 (0.44-0.85), and 0.82 (0.69-0.91), respectively. The overall accuracy of the N/L ratio in determination of FMF patients during attack was 71%. Our results demonstrate that N/L ratio is higher in patients with active FMF compared with FMF patients in remission and controls, and a cut-off value of 2.63 can be used to identify patients with active FMF.

Neutrophil–Lymphocyte Ratio and Carotid–Intima Media Thickness in Patients With Behçet Disease Without Cardiovascular Involvement

Behçet disease (BD) is associated with endothelial dysfunction and chronic inflammation. The neutrophil-lymphocyte (N/L) ratio and carotid intima-media thickness (cIMT) are markers of inflammation and vascular risk, respectively. We assessed the relationship between cIMT values and N/L ratio in BD (65 patients and 62 control participants). There were statistically significant differences in N/L ratios and cIMT values between the patients with BD and control group (P < .001). There were moderate positive correlations between cIMT value, C-reactive protein, and N/L ratio in patients with BD. Receiver-operating characteristic curve analysis suggested that the optimum N/L ratio cutoff point for patients with BD was 1.29, with a sensitivity, specificity, negative predictive value, and positive predictive value of 97, 77, 96, and 75%, respectively (area under curve: 0.691, 95% confidence interval = 0.600-0.782, P < .001). The N/L ratio may be a useful index of BD activity.

Spot urine protein–creatinine ratio and 24-h urine protein excretion: Diagnostic accuracy in women with pre-eclampsia

To compare the efficacy of spot urinary protein/creatinine ratio with 24h urinary protein excretion in women with pre-eclampsia. A total of 85 women with hypertensive disorders during pregnancy were prospectively studied. Urine protein/creatinine ratio in spot urine sample was compared with 24h urinary protein. Sensitivity and specificity for urinary spot P/C (protein/creatinine) ratio was assessed, and receiver operating curve was used to determine the value against the gold standard of >300mg proteinuria in 24h urinary sample. Of 85 women, complete data were available for 81 women. There was a strong correlation between spot urinary P/C ratio and 24h urine protein excretion (r=0.81, P value <0.000). The optimal spot P/C ratio cut-off point was 0.14 for 300mg/24h of protein excretion (preeclampsia) with a sensitivity of 82% and specificity of 79%. We found a strong correlation between spot urinary P/C and 24h urinary protein. Spot urinary protein/creatinine ratio is a good predictor of proteinuria for pre-eclampsia.

Validation and Initial Application of a Semiautomatic Aneurysm Measurement Software: A Tool for Assessing Volumetric Packing Attenuation

Precise aneurysm measurements and volume embolization ratios are essential for long-term durability of endovascular coil embolization. We evaluated the accuracy of newly developed semiautomatic cerebral aneurysm measurement software, NeuroVision, and explored the value of volume embolization ratio in the prediction of re-treatment. We compared software-derived volume measurements of 4 silicone aneurysm models with those calculated with an approximation formula and ground truth values (validation study). We used NeuroVision to retrospectively evaluate outcomes of 100 unruptured aneurysms (97 patients) treated with embolization (clinical study). Aneurysm size (height, width, and neck), volume, and volume embolization ratios were calculated for 3 groups (stable, recanalization, and re-treatment) and were compared. This validation study illustrated higher accuracy of NeuroVision in computing aneurysm volume compared with an approximation formula: percentage absolute errors were 4.50% ± 3.18% and 23.07% ± 17.60%, with maximal percentage absolute errors of 8.99% and 45.63%, respectively. Of 100 unruptured aneurysms, 20 recanalized and 12 were re-treated. Average volume embolization ratios of stable and re-treated aneurysms were 24.88% ± 5.91% and 20.50% ± 4.06%, respectively (P ≤ .01). The optimal volume embolization ratio cutoff point for re-treatment was < 19.15%, at which the Youden index was 0.50 (sensitivity, 58.33%; specificity, 87.50%; area under the receiver operating characteristic curve, 0.74). The NeuroVision software provided accurate aneurysm volume measurements and may be a useful standardized tool to measure aneurysm size and volume, especially for multicenter clinical studies. Volume embolization ratio may be a valuable predictor of aneurysm occlusion changes.

Cardiometabolic and behavioural risk factors in young overweight women identified with simple anthropometric measures

This study aimed to (1) investigate cardiometabolic risk markers in young women (18-30 years) with overweight/obesity, and (2) establish whether the measures of waist circumference and body mass index possess similar associations of cardiometabolic risk. Cross-sectional. Cardiometabolic risk factors including, anthropometric, metabolic syndrome markers, biochemical, and other health/fitness indicators were assessed in women when classified as overweight/obese by waist circumference [waist circumference 91.9 ± 10.1 cm, age 22.3 ± 3.5 years, n = 38] versus control [n = 30, waist circumference 71.4 ± 3.5 cm, age 20.1 ± 0.9 years], and when classified by body mass index [n=35, body mass index 32.2 ± 5.2 kg m(2), age 22.5 ± 3.6 years] versus control [body mass index 21.7 ± 1.9 kg m(2), age 20.1 ± 0.9 years, n=33]. Compared with controls, women with overweight/obesity (classified by waist circumference or body mass index) displayed elevated body mass, systolic blood pressure and homeostasis model assessment of insulin resistance, and reduced estimated [Formula: see text] and weekly physical activity, with no differences in self-reported energy intake. The unadjusted odds ratio of being classified with overweight/obesity and an elevated homeostasis model assessment of insulin resistance and/or less than recommended physical activity ranged between 5.1 and 10.0. Receiver operator characteristic curves indicated waist circumference, body mass index and waist-to-height ratio cut-off points of ≥ 84.2 cm, ≥ 30.6 kg m(-2) and ≥ 0.5, respectively, for homeostasis model assessment of insulin resistance, and ≥ 80.6 cm, ≥ 25.2 kg m(-2) and ≥ 0.46, respectively, for less than recommended physical activity. Waist circumference and body mass index have similar associations with cardiometabolic risk, with greater homeostasis model assessment of insulin resistance and lower physical activity, rather than differences in traditional metabolic syndrome markers, observed in young women with overweight/obesity.

Agreement Between Fixed-Ratio and Lower Limit of Normal Spirometry Interpretation Protocols Decreases With Age

To assess concordance between the fixed 70% ratio cutoff point with the fixed percent predicted values (Fixed-ratio) and the lower limit of normal (LLN) algorithms in interpreting spirometry results in an older population. Spirometries were interpreted using Third National Health and Nutrition Examination Survey reference equations for 2319 workers. The Fixed-ratio algorithm characterized 34.5% (n = 801) results as abnormal, compared with 29.7% (n = 689) by the LLN. There were almost twice as many obstructive and mixed airways spirometries identified under the Fixed-ratio compared to LLN. Rates of restrictive pattern physiology were virtually the same under each algorithm. Overall agreement between the algorithms decreased with age from "almost perfect" for those younger than 60 years to "substantial" for those older than 80 years. This study found age-related discordance between two algorithms possibly related to the lack of reference equations and standards for individuals older than 80 years.

The relation between lymph node status and survival in Stage I–III colon cancer: results from a prospective nationwide cohort study

This study involved a large nationwide Danish cohort to evaluate the hypothesis that a high lymph node harvest has a positive effect on survival in curative resected Stage I-III colon cancer and a low lymph node ratio has a positive effect on survival in Stage III colon cancer. Analysis of overall survival was conducted using a nationwide Danish cohort of patients treated with curative resection of Stage I-III colon cancer. All 8901 patients in Denmark diagnosed with adenocarcinoma of the colon and treated with curative resection in the period 2003-2008 were identified from the Danish Colorectal Cancer Group (DCCG). The impact of lymph node count and lymph node ratio was analysed. Overall 5-year survival was 56.8 and 66.6%, (P<0.0001) for lymph node counts of fewer than 12 and 12 or more, respectively. The percentages of lymph node positive patients in the two groups were 29.8 and 40.3% (P<0.0001), respectively. When putting the Stage III patients into four subgroups according to the lymph node ratio (cut-off points 1/12, 1/4 and 1/2) we found an overall 5-year survival rate of 68.1, 57.2, 49.3 and 32.4% (P<0.0001). Lymph node count and lymph node ratio were independent prognostic factors in multivariate analysis. High lymph node count was associated with improved overall survival in colon cancer. Lymph node ratio was superior to N-stage in differentiating overall survival in Stage III colon cancer. Stage migration was observed.

COPD prognosis in relation to diagnostic criteria for airflow obstruction in smokers

The aim of this study was to establish which cut-off point for the forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) ratio (i.e. fixed 0.70 or lower limit of normal (LLN) cut-off point) best predicts accelerated lung function decline and exacerbations in middle-aged smokers. We performed secondary analyses on the Lung Health Study dataset. 4045 smokers aged 35-60 years with mild-to-moderate obstructive pulmonary disease were subdivided into categories based on presence or absence of obstruction according to both FEV1/FVC cut-off points. Post-bronchodilator FEV1 decline served as the primary outcome to compare subjects between the categories. 583 (14.4%) subjects were nonobstructed and 3230 (79.8%) subjects were obstructed according to both FEV1/FVC cut-off points. 173 (4.3%) subjects were obstructed according to the fixed cut-off point, but not according to the LLN cut-off point ("discordant" subjects). Mean±SE post-bronchodilator FEV1 decline was 41.8±2.0 mL·year(-1) in nonobstructed subjects, 43.8±3.8 mL·year(-1) in discordant subjects and 53.5±0.9 mL·year(-1) in obstructed subjects (p<0.001). Our study showed that FEV1 decline in subjects deemed obstructed according to a fixed criterion (FEV1/FVC <0.70), but non-obstructed by a sex- and age-specific criterion (LLN) closely resembles FEV1 decline in subjects designated as non-obstructed by both criteria. Sex and age should be taken into account when assessing airflow obstruction in middle-aged smokers.

Random urine protein/creatinine ratio readily predicts proteinuria in preeclampsia

ObjectiveTo assess the diagnostic accuracy of random urine protein-creatinine (P/C) ratio for prediction of significant proteinuria in preeclampsia as an alternative to the time-consuming 24-hour urine protein collection.MethodsRetrospective record analysis was performed on 140 pregnant women who were admitted with suspicion for preeclampsia from January 2006 to June 2011. Random urine protein and/or 24-hour urine protein levels were assessed and their correlation to random urine P/C ratio and 24-hour urine protein excretion was evaluated.ResultsOut of 140 patients, random urine P/C ratio or/and 24-hour urine protein was performed in 79 patients to evaluate significant proteinuria. Of 79 patients, 46 (58%) underwent both tests whereas in 33 women (42%) 24-hour urine collection was not available due to urgent delivery. In 39 cases (85%), significant proteinuria (≥300 mg/24 hr) was detected with 6 cases (13%) having values over 5,000 mg/24 hr, corresponding to the diagnosis of severe preeclampsia. Random urine P/C ratio highly correlated with 24-hour urine protein excretion (r=0.823, P<0.01). The optimal random urine P/C ratio cutoff points were 0.63 and 4.68 for 300 mg/24 hr and 5,000 mg/24 hr of protein excretion, respectively. with each sensitivity, specificity, and positive and negative predictive values of 87.1%, 100%, 100%, and 58.3%; and 100%, 85%, 50%, and 100%, for significant and severe preeclampsia, respectively.ConclusionRandom urine P/C ratio is a reliable indicator of significant proteinuria in preeclampsia and may be better at providing earlier diagnostic information than the 24-hour urine protein excretion with more accuracy than the urinary dipstick test.

Can the ratio of metastatic to examined lymph nodes (N ratio) be used as an independent prognostic factor in patients with gastric cancer? Is the hypothetical TRM (tumor-ratio-metastasis) staging system an alternative to the TNM (tumor-node-metastasis) staging system?

ENWEndNote BIBJabRef, Mendeley RISPapers, Reference Manager, RefWorks, Zotero AMA Ilhan E, Zengel B, Simsek H, Canpolat S, Yildirim M. Can the ratio of metastatic to examined lymph nodes (N ratio) be used as an independent prognostic factor in patients with gastric cancer? Is the hypothetical TRM (tumor-ratio-metastasis) staging system an alternative to the TNM (tumor-node-metastasis) staging system?. Gastroenterology Review/Przegląd Gastroenterologiczny. 2013;8(4):247-256. doi:10.5114/pg.2013.37488. APA Ilhan, E., Zengel, B., Simsek, H., Canpolat, S., & Yildirim, M. (2013). Can the ratio of metastatic to examined lymph nodes (N ratio) be used as an independent prognostic factor in patients with gastric cancer? Is the hypothetical TRM (tumor-ratio-metastasis) staging system an alternative to the TNM (tumor-node-metastasis) staging system?. Gastroenterology Review/Przegląd Gastroenterologiczny, 8(4), 247-256. https://doi.org/10.5114/pg.2013.37488 Chicago Ilhan, Enver, Baha Zengel, Hatice Simsek, Selin Canpolat, and Mehmet Yildirim. 2013. "Can the ratio of metastatic to examined lymph nodes (N ratio) be used as an independent prognostic factor in patients with gastric cancer? Is the hypothetical TRM (tumor-ratio-metastasis) staging system an alternative to the TNM (tumor-node-metastasis) staging system?". Gastroenterology Review/Przegląd Gastroenterologiczny 8 (4): 247-256. doi:10.5114/pg.2013.37488. Harvard Ilhan, E., Zengel, B., Simsek, H., Canpolat, S., and Yildirim, M. (2013). Can the ratio of metastatic to examined lymph nodes (N ratio) be used as an independent prognostic factor in patients with gastric cancer? Is the hypothetical TRM (tumor-ratio-metastasis) staging system an alternative to the TNM (tumor-node-metastasis) staging system?. Gastroenterology Review/Przegląd Gastroenterologiczny, 8(4), pp.247-256. https://doi.org/10.5114/pg.2013.37488 MLA Ilhan, Enver et al. "Can the ratio of metastatic to examined lymph nodes (N ratio) be used as an independent prognostic factor in patients with gastric cancer? Is the hypothetical TRM (tumor-ratio-metastasis) staging system an alternative to the TNM (tumor-node-metastasis) staging system?." Gastroenterology Review/Przegląd Gastroenterologiczny, vol. 8, no. 4, 2013, pp. 247-256. doi:10.5114/pg.2013.37488. Vancouver Ilhan E, Zengel B, Simsek H, Canpolat S, Yildirim M. Can the ratio of metastatic to examined lymph nodes (N ratio) be used as an independent prognostic factor in patients with gastric cancer? Is the hypothetical TRM (tumor-ratio-metastasis) staging system an alternative to the TNM (tumor-node-metastasis) staging system?. Gastroenterology Review/Przegląd Gastroenterologiczny. 2013;8(4):247-256. doi:10.5114/pg.2013.37488.

Neutrophil–Lymphocyte Ratio as a Predictor of Disease Severity in Ulcerative Colitis

Blood neutrophil-to-lymphocyte (N/L) ratio is an indicator of the overall inflammatory status of the body, and an alteration in N/L ratio may be found in ulcerative colitis (UC) patients. The aims of this study were to investigate the utility of N/L ratio as a simple and readily available predictor for clinical disease activity in UC. Twenty-six patients and 28 healthy controls were enrolled in the study. The neutrophil and lymphocyte counts were recorded, and the N/L ratio was calculated from these parameters. The extent of disease classified according to the Montreal classification, clinical disease activity was evaluated using a modified Truelove-Witts severity index, and endoscopic disease activities were classified according to Schroder et al. The serum N/L ratios of active patients were significantly higher than those of inactive UC and controls (P < 0.001). The optimum N/L ratio cut-off point for active UC was 2.47. There was no significant difference between inflammation parameters, disease extension, and disease activity. Our results demonstrate that N/L ratio is higher in patients with active UC compared with controls and UC patients in remission and a cut-off value of 2.47 can be used to identify patients with active ulcerative colitis.

Breast Sonographic Elastography Using an Advanced Breast Tissue‐Specific Imaging Preset

The purpose of this study was to evaluate the interpretation criteria, such as the size ratio, stain ratio, and elasticity score, and to assess the diagnostic performance of sonographic elastography by using an advanced breast tissue-specific imaging preset compared with that of conventional sonography for the differentiation of benign and malignant breast masses. Conventional sonography and sonographic elastography with the tissue-specific imaging preset were performed in 104 patients (age range, 17-76 years; mean age, 47.7 years) with 110 breast lesions (67 benign and 43 malignant; mean size, 1.69 cm). The data from the interpretation criteria of sonographic elastography were obtained. The pathologic results from surgical excision or vacuum-assisted removal were used as a reference standard. The values for the area under the receiver operating characteristic curve were 0.959 (95% confidence interval [CI], 0.902-0.987) for conventional sonography and 0.901 (95% CI, 0.829-0.949), 0.796 (95% CI, 0.708-0.866), and 0.787 (95% CI, 0.699-0.859) for the strain ratio, size ratio, and elasticity score, respectively. When a strain ratio cutoff point of 4.215 was used, the sensitivity and specificity were 86.0% and 85.1%. With a best cutoff point for conventional sonography between Breast Imaging Reporting and Data System categories 4A and 4B, the sensitivity and specificity were 93.0% and 83.6%. The strain ratio showed the best diagnostic performance among the interpretation criteria for sonographic elastography with the tissue-specific imaging preset. The diagnostic performance was slightly higher for Breast Imaging Reporting and Data System categories than for the strain ratio. However, there was no statistical significance (P = .052).

Defining Glaucomatous Optic Neuropathy from a Continuous Measure of Optic Nerve Damage – The Optimal Cut-off Point for Risk-factor Analysis in Population-based Epidemiology

Purpose: Diseases characterized by a continuous trait can be defined by setting a cut-off point for the disease measure in question, accepting some misclassification. The 97.5th percentile is commonly used as a cut-off point. However, it is unclear whether this percentile is the optimal cut-off point from the point of view of risk-factor analysis. The optimal cut-off point for risk-factor analysis can be found with a statistical method that minimizes the effect of misclassification. We applied this method to glaucomatous optic neuropathy. Here, the continuous trait is the cup-disc ratio. The aim of this study was to determine the optimal cup-disc ratio cut-off point for risk-factor analysis in population-based epidemiology.Methods: All participants in the population-based Rotterdam Study underwent intraocular pressure (IOP) measurements, assessment of the cup-disc ratio with the Heidelberg Retina Tomograph (HRT) and visual field testing. In the statistical method, the cup-disc ratio (the continuous trait) and the IOP (a major risk factor) were independent variables and glaucomatous visual field loss (the true glaucoma endpoint) the dependent variable in a logistic regression model. The optimal cup-disc ratio cut-off point was found by minimizing the influence of IOP in this model. Variability of the approach was assessed by using a bootstrap resampling technique.Results: Of 2444 included participants, 93 had glaucomatous visual field loss. The median optimal cup-disc ratio cut-off point was the 97.0th percentile with a 95% central range from 95.5 to 98.5.Conclusion: The optimal cup-disc ratio cut-off point for risk-factor analysis is close to the commonly used 97.5th percentile.

Role of Sonographic Elastography in the Differential Diagnosis of Axillary Lymph Nodes in Breast Cancer

The purpose of this study was to evaluate the diagnostic utility of sonographic elastography in differentiating reactive and metastatic axillary lymph nodes in breast cancer. A total of 64 lymph nodes (reactive, n = 33; metastatic, n = 31) from 62 patients with breast cancer were examined by both B-mode sonography and elastography from April to July 2009. Two experienced radiologists retrospectively assessed B-mode sonograms by the sum of scores for 4 criteria: short diameter, shape, hilum, and cortical thickening. Elastographic images were given scores of 1 to 4 according to the percentage of high-elasticity areas in the lymph nodes. We compared the diagnostic performance of B-mode sonography, elastography, and combined examinations. We also calculated the strain ratio of the lymph node and subcutaneous fat tissue. The elasticity score for malignant lymph nodes (mean, 3.1) was higher than the score for benign lymph nodes (mean, 2.2; P < .0001). With a cutoff between elasticity scores of 2 and 3, elastography showed 80.7% sensitivity, 66.7% specificity, and 73.4% accuracy. With a cutoff between B-mode sonographic scores of 1 and 2, B-mode sonography showed 74.2% sensitivity and 78.8% specificity. Combined B-mode and elastographic sonography showed higher sensitivity (87.1%) than B-mode sonography alone. With a strain ratio cutoff point of 2.3, sensitivity was 82.8%, and specificity was 56.3%. Sonographic elastography may increase the sensitivity of B-mode sonography in the detection of metastatic axillary lymph nodes.

The value of computed tomographic obstruction index in the identification of massive pulmonary thromboembolism

In this study, the pulmonary arterial computed tomography obstruction index ratio, which indicates the degree and extent of thrombotic arterial occlusion, was calculated in cases with pulmonary thromboembolism. Our objectives were to investigate the value of this index for the identification of cases with massive pulmonary thromboembolism and to search for correlations between this index and clinical parameters. Data from 68 patients were evaluated retrospectively. For the clinical evaluation, the Wells scoring system was used. Pulmonary computed tomographic angiography examinations were acquired using an eight-channel multidetector computed tomography. The presence of arterial filling defects was recorded, and the clot burden was quantified based on the degree and extent of thrombotic arterial occlusion. According to the Wells scoring system, the patients were assigned to low (n = 14), moderate (n = 34), and high clinical (n = 20) possibility groups, and the difference among the mean pulmonary arterial computed tomography obstruction index ratios of the three groups was significant (P = 0.001). A positive correlation was observed between the pulmonary arterial computed tomography obstruction index ratio and the Wells score (r = 0.470, P < 0.001). The pulmonary arterial computed tomography obstruction index ratio cut-off point was determined to be 40% for the discrimination of massive and nonmassive cases (sensitivity, 72.7%; specificity, 91.4%). We found that in cases where the pulmonary arterial computed tomography obstruction index ratio was above 40%, a diagnosis of massive pulmonary thromboembolism was demonstrated. Furthermore, a positive correlation between the obstruction index and the Wells score suggested the use of a clinical evaluation as a means of developing a recommendation regarding the thrombotic load.

Optimal waist:height ratio cut-off point for cardiometabolic risk factors in Turkish adults

To identify the optimal waist:height ratio (WHtR) cut-off point that discriminates cardiometabolic risk factors in Turkish adults. Cross-sectional study. Hypertension, dyslipidaemia, diabetes, metabolic syndrome score >or=2 (presence of two or more metabolic syndrome components except for waist circumference) and at least one risk factor (diabetes, hypertension or dyslipidaemia) were categorical outcome variables. Receiver-operating characteristic (ROC) curves were prepared by plotting 1 - specificity on the x-axis and sensitivity on the y-axis. The WHtR value that had the highest Youden index was selected as the optimal cut-off point for each cardiometabolic risk factor (Youden index = sensitivity + specificity - 1). Turkey, 2003. Adults (1121 women and 571 men) aged 18 years and over were examined. Analysis of ROC coordinate tables showed that the optimal cut-off value ranged between 0.55 and 0.60 and was almost equal between men and women. The sensitivities of the identified cut-offs were between 0.63 and 0.81, the specificities were between 0.42 and 0.71 and the accuracies were between 0.65 and 0.73, for men and women. The cut-off point of 0.59 was the most frequently identified value for discrimination of the studied cardiometabolic risk factors. Subjects classified as having WHtR >or= 0.59 had significantly higher age and sociodemographic multivariable-adjusted odds ratios for cardiometabolic risk factors than subjects with WHtR < 0.59, except for diabetes in men. We show that the optimal WHtR cut-off point to discriminate cardiometabolic risk factors is 0.59 in Turkish adults.