A Comparison of Single Dimension and Volume Measurements in the Risk Stratification of Pancreatic Cystic Lesions.

The incidence of pancreatic cystic lesions (PCLs) has been rising due to improvements in imaging. Of these, intraductal papillary mucinous neoplasms (IPMNs) are the most common and are thought to contribute to almost 20% of pancreatic adenocarcinomas. All major society guidelines for the management of IPMNs use size defined by maximum diameter as the primary determinant of whether surveillance or surgical resection is recommended. However, there is no consensus on how these measurements should be obtained or whether a single imaging modality is superior. Furthermore, the largest diameter may fail to capture the complexity of PCLs, as most are not perfectly spherical. This article reviews current PCL measurement techniques in CT, MRI, and EUS and posits volume as a possible alternative to the largest diameter.

Predictive value of serum interleukin-6 to determine surgical drainage of deep neck space infection in adults.

PURPOSE: The aim of this study was to determine whether interleukin-6 (IL-6) could be used as a predictor for surgical drainage in deep neck space infection (DNSI). METHODS: A retrospective study was conducted to analyze 69 adult patients newly diagnosed as DNSI from January 2017 to December 2021 at a single center. The patients were treated with either surgical drainage or not. The following clinical data including age, gender, maximum diameter of abscess (MDA), laboratory data, therapeutic modalities, comorbidities, duration of hospitalization and complications were collected and evaluated. RESULTS: Patients in drained group had significantly elevated MDA, IL-6, procalcitonin, C-reactive protein and neutrophil to lymphocyte ratio compared to patients in non-drained group (all P < 0.01). Significant predictors for surgical drainage were IL-6 and MDA as independent factors, with the optimum cutoff values of 52.5 pg/mL and 14.4 mm, respectively. Moreover, the IL-6 had a wider area under the curve than MDA for prediction of surgical drainage in DNSI. CONCLUSIONS: IL-6 as a promising predictor of the need for surgical drainage can be effectively used for routine assessment in the early stage of DNSI to determine the optimal treatments.

The effect of time delay for magnetic resonance contrast-enhanced scan on imaging for small-volume brain metastases.

PURPOSE: To study the effect of different enhancement timings of magnetic resonance (MR) on small-volume brain metastases (BM) visualisation and provide a basis for the contour of tumour targets. METHOD: We prospectively enrolled 101 patients with BM who received radiotherapy. All patients underwent computed tomography (CT) and MR simulations. Contrast-enhanced MR scans at 1, 3, 5, 10, 18, and 20 min after injection of contrast medium were performed. The tumour target was determined on MR images at different enhancement times, and the differences of tumour target volume, maximum diameter, and MR signal intensity were compared. RESULTS: (1) Of the 453 metastatic lesions, 24 (5.2 %) were not detected at 1 min and 8 (1.8 %) were not detected at 3 min; however, all metastases were detected after 5 min. The volume and maximum diameter of the 28 (6.2 %) metastases were stable at any time. (2) The average volume of metastatic lesions at 1, 3, 5, 10, 18, and 20 min was 0.09 cm3, 0.10 cm3, 0.12 cm3, 0.12 cm3, 0.13 cm3, and 0.13 cm3, respectively. Compared to 1 min, BM volume at other times increased by 13.1 %, 21.5 %, 31.6 %, 39.6 %, and 41.7 %, and the difference between the maximum and minimum volumes was statistically significant (p < 0.05). (3) The distribution of the maximum ratio of tumours to white matter mean signal intensity at different times were 39.6 %, 20 %, 14.6 %, 8.0 %, 10.4 %, and 10 %, respectively. CONCLUSION: The visualisation of small-volume BM was significantly different at different enhancement times. Our results suggest that multi-timing enhancement scans for small-volume BM should be implemented and that scanning at >10 min is essential.

Influential factors of stereotactic radiotherapy for primary liver cancer / 中国基层医药

Objective:To investigate the factors affecting the therapeutic effects of stereotactic radiotherapy on primary liver cancer.Methods:The clinical data of 116 patients with primary liver cancer who received stereotactic radiotherapy in Binzhou Central Hospital from February 2018 to April 2020 were retrospectively analyzed. The factors that affect the therapeutic effects of stereotactic radiotherapy on primary liver cancer were analyzed.Results:Stereotactic radiotherapy was effective in 85 patients, with an overall response rate of 73.28%. There were no significant differences in maximum tumor diameter, arteriovenous fistula, portal vein tumor thrombus, distant metastasis, pseudocapsule, liver function Child-Pugh grade, Barcelona clinic liver cancer staging, and the number of stereotactic radiotherapies between different patients ( χ2 = 14.71, 12.76, 19.16, 8.54, 7.30, 7.71, 9.41, 4.08, P < 0.05 or < 0.01). Maximum tumor diameter, portal vein tumor thrombus, pseudocapsule, liver function Child-Pugh grade, Barcelona clinic liver cancer staging, and the number of stereotactic radiotherapies were the independent risk factors that affect the therapeutic effects of stereotactic radiotherapy on primary liver cancer (Wald χ2 = 3.13, 3.75, 4.16, 5.20, 3.90, 3.40, all P < 0.05). Conclusion:Many factors affect the therapeutic effects of stereotactic radiotherapy on primary liver cancer. Early identification of the high-risk factors for primary liver cancer is conducive to minimizing the risk of stereotactic radiotherapy, improving the therapeutic effects of stereotactic radiotherapy, and improving the prognosis. This study is highly innovative and scientific.

Pulmonary perfusion defect index, pulmonary artery obstruction index and right heart function parameters for evaluating the severity of pulmonary embolism / 中国基层医药

Objective:To investigate the value of pulmonary perfusion defect index (PPDI), pulmonary artery obstruction index (PAOI) and right heart function parameters in the evaluation of severity of pulmonary embolism.Methods:The clinical data of 108 patients with pulmonary embolism who received treatment in The Second Hospital of Jiaxing from January 2019 to June 2021 were retrospectively analyzed. These patients were divided into high-risk ( n = 25), moderate-risk ( n = 32), and low-risk ( n = 51) groups according to the severity of pulmonary embolism. PAOI, PPDI, right ventricular short axis maximum diameter (RV), left ventricular short axis maximum diameter (LV), ratio of right/left right ventricular short axis maximum diameter (RV/LV) were determined in each group. PPDI, PAOI and right ventricular function parameters were correlated with the severity of pulmonary embolism. The area under the receiver operating characteristic curve, specificity and severity of PPDI, PAOI, RV, LV, RV/LV used alone and in combination to predict the severity of pulmonary embolism were analyzed. Results:PPDI, PAOI, RV, and RV/LV in the high-risk group were (32.52 ± 10.85)%, (45.01 ± 15.02)%, (50.32 ± 12.32) mm, (1.42 ± 0.45), respectively, which were significantly lower than (5.32 ± 1.85)%, (12.52 ± 3.25)%, (37.25 ± 8.52) mm, (0.96 ± 0.21) in the low-risk group, and LV was significantly lower in the high-risk group than that in the low-risk group [(35.14 ± 10.52) mm vs. (44.02 ± 15.21) mm, t = 13.95, 11.91, 2.62, 6.09, 5.44, all P < 0.05]. PPDI, PAOI, RV, and RV/LV in the moderate-risk group were (18.62 ± 6.02)%, (28.65 ± 8.65)%, (45.85 ± 10.02) mm, and (1.20 ± 0.32), respectively, which were significantly higher than those in the low-risk group ( t = 14.75, 12.06, 4.18, 4.13, all P < 0.05). There was no significant difference in LV between moderate-risk and low-risk groups ( t = 1.51, P > 0.05). Spearman correlation analysis showed that PPDI, PAOI, RV, RV/LV were positively correlated with the severity of pulmonary embolism ( r = 0.87, 0.84, 0.45, 0.41, all P < 0.001). LV was negatively correlated with the severity of pulmonary embolism ( r = -0.27, P < 0.001). The receiver operating characteristic curve (ROC curve) showed that the areas under the receiver operating characteristic curve of PPDI, PAOI, RV, LV, RV/LV used alone or in combination to predict the severity of pulmonary embolism were 0.941, 0.911, 0.721, 0.693, 0.726, and 0.951, respectively (all P < 0.001). Conclusion:PPDI, PAOI and right heart function parameters can be used as effective indexes to dynamically monitor the severity of pulmonary embolism.

Análisis volumétrico e influencia del trombo intraluminal tras la reparaciónendoluminal del aneurisma de aorta abdominal / Volumetric analysis and influence of intraluminal thrombus after endoluminal repair of abdominal aortic aneurysm

Objetivo: la precisión de la predicción del riesgo de rotura mediante control ultrasonográfico y angiotomografía computarizada está todavía lejos del método de diagnóstico óptimo para el aneurisma de aorta abdominal (AAA). El objetivo de este estudio es realizar un análisis volumétrico del saco aneurismático, comparar sus modificaciones con las del diámetro máximo, estudiar la evolución del volumen del trombo intraluminal (ILT) después de la reparación endovascular del AAA. Métodos: se analizaron un total de 144 AAA reparados por la EVAR electiva. Se realizó una angiotomografía en el periodo preoperatorio, 6-12 meses después de la intervención quirúrgica. Se calculó el diámetro máximo, el volumen del saco aneurismático y el volumen de la ILT en los tres momentos. Se determinó la modificación del diámetro, el volumen total y el volumen del trombo intraluminal (%). Se comparó la modificación del diámetro máximo con el volumen total de los aneurismas y entre el volumen total del aneurisma y el volumen del trombo intraluminal. Resultados: la media de los cambios en el diámetro máximo del AAA y el volumen después de la EVAR fue de -2,16 ± 8,20 mm y 84,4 ± 23,32 cc, respectivamente. Hubo un aumento en el volumen de AAA de 92,22 % y 57,34 % a los 6 y 12 meses en pacientes con endofugas (22.03 ± 19.03 cc a los 12 meses del periodo posoperatorio). La modificación media del ITL y del saco aneurismático fue de 0,59 ± 0,17 y 0,52 ± 1,8 para los pacientes con AAA presurizados y no presurizados, respectivamente (p = 0,308). Conclusión: el análisis volumétrico de los AAA reparados mediante tratamiento endovascular es una medida más preciso que la medición del diámetro máximo para determinar la expansión del saco aneurismático.(AU)

Purpose: the accuracy of risk prediction by ultrasonic control and computerized angiotomography is still far from the optimal diagnostic method for abdominal aortic aneurysm (AAA). The objective of this study is to perform a volumetric analysis of the AAA sac to detect alterations and to follow-up the evolution of the volume of the intraluminal thrombus (ILT) and its influence on the overall evolution after the EVAR. Methods: a total of 144 AAAs repaired by elective EVAR were analyzed. An angiotomography was carried out in the preoperative period, 6-12 months after the operation. The maximum-diameter, aneurysmal sac volume, and ILT volume were calculated each time. We determined the modification of the diameter, total-volume and intraluminal-thrombus volume (%). We made a comparison between the modification of the maximum-diameter and the total-volume of the aneurysms and between the total-volume of the aneurysm and the volume of ILT. Results: the average changes in the maximum diameter of AAA and the volume after EVAR was -2.16 ± 8.20 mm and 84.4 ± 23.32 cc, respectively. There was an increase in AAA-volume of 92.22 % and 57.34 % at 6 and 12 months in patients with endoleaks (22.03 ± 19.03 cc at 12 months of postoperative-period). The means of the ILT and AAA sac ratios were respectively 0.59 ± 0.17 and 0.52 ± 1.8 in AAA in sac growth and in stable or contracted AAA sac groups (p = 0.308). Conclusion: volumetric analysis of AAA repaired by EVAR is a more sensitive measure to determine the expansion of the aneurysm sac than the measurement of the maximum diameter of the aneurysm.(AU)

Splenic Vein Diameter is a Risk Factor for the Portal Venous System Thrombosis After Partial Splenic Artery Embolization.

PURPOSE: Portal venous system thrombosis is a complication of partial splenic artery embolization, and pre-treatment risk assessment is thus important. The purpose of this study was to identify the risk factors for portal venous system thrombosis after partial splenic artery embolization. MATERIALS AND METHODS: We retrospectively analyzed 67 consecutive patients who underwent contrast-enhanced computed tomography before and after first partial splenic artery embolization between July 2007 and October 2018. As risk factors, we investigated age, sex, hematological data, liver function, steroid use, heparin use, and findings from pre- and post-treatment computed tomography. Uni- and multivariate analyses were performed to evaluate the relationship between thrombus appearance or growth and these factors. Values of p < 0.05 were considered significant. RESULTS: Partial splenic artery embolization was technically successful in all 67 patients. Nine patients showed appearance or growth of thrombus. Univariate analysis showed maximum diameter of the splenic vein before treatment (p = 0.0076), percentage of infarcted spleen (p = 0.017), and volume of infarcted spleen (p = 0.022) as significant risk factors. Multivariate analysis showed significant differences in maximum diameter of the splenic vein before treatment (p = 0.041) and percentage of infarcted spleen (p = 0.023). According to receiver operating characteristic analysis, cutoffs for maximum diameter of the splenic vein and percentage of infarcted spleen for distinguishing the appearance or growth of thrombus were 17 mm and 58.2%. CONCLUSION: Large maximum diameter of the splenic vein before partial splenic artery embolization and high percentage of infarcted spleen after partial splenic artery embolization were identified as risk factors for portal venous system thrombosis. LEVEL OF EVIDENCE: Level 4, Case Series.

Effect of Pulse Energy, Pulse Frequency, and Tip Diameter on Intracanal Vaporized Bubble Kinetics and Apical Pressure During Laser-Activated Irrigation Using Er:YAG Laser.

Objective: Er:YAG laser-activated irrigation (LAI) is an effective method of root canal cleaning, but irrigant extrusion from the apical foramen has been a concern. We aimed to analyze the effects of pulse energy, pulse frequency, and laser tip diameter on intracanal vapor bubble kinetics and periapical pressure generation during LAI with Er:YAG laser. Background: Irrigant vapor bubble kinetics are one of indices of root canal cleaning efficacy. However, few studies have compared laser pulse conditions to vapor bubble kinetics, in relation to periapical pressure. Methods: A plastic root canal model (apical diameter 0.50 mm, 6% taper, 20 mm long) was filled with distilled water, and LAI with Er:YAG laser (Erwin AdvErl Unit; 30, 50, or 70 mJ; 10, or 20 pulses per second; laser tip R200T or R600T) was performed with the end of the tip fixed at 15 mm from the root apex. The number, maximum diameter, and velocity of vapor bubbles were analyzed by high-speed video imaging. Pressure generated outside the apical foramen was measured with a pressure sensor. Results: Vapor bubble count and maximum diameter increased significantly with pulse energy, pulse frequency, and tip diameter. Vapor bubble velocity increased significantly with pulse frequency, but not with pulse energy or tip diameter. Periapical pressure increased significantly with pulse energy, pulse frequency, and tip diameter. Conclusions: The pulse frequency was the single factor that significantly affected all the examined parameters (the number, diameter, and velocity) of vapor bubble kinetics together with the periapical pressure.

Value of imaging findings in predicting post-operative recurrence of desmoid-type fibromatosis.

Desmoid-type fibromatosis is a rare type of soft-tissue tumor originating from connective tissue of the fascia or aponeurosis, which exhibits aggressive growth, high likelihood of relapse and less frequent distant metastasis. The present study aimed to predict the recurrence rate and time by retrospectively analyzing the clinical data (sex, age and recurrence time), imaging findings [tumor location, maximum diameter, border, computed tomography (CT) enhancement ratio, magnetic resonance enhancement ratio and T2 signal ratio] and pathological features (Ki-67 and microscopic margin) in a total of 102 cases of pathologically confirmed desmoid-type fibromatosis. The risk ratio of each factor was calculated using the Cox proportional hazards regression model and the cumulative recurrence-free survival rate was determined using the Kaplan-Meier method and the log-rank test. The cohort comprised of 73 females and 29 males, with mean age of 32.86±12.64 years (range, 6-78 years). The 1-year and 2-year recurrence rate was 31 and 54%, respectively. The median age at recurrence was 29 years. Univariate analysis indicated that sex, maximum tumor diameter, CT enhancement ratio and Ki-67 had a significant effect on the recurrence time. Furthermore, multivariate analysis revealed that sex, maximum tumor diameter, Ki-67 and T2 signal ratio were independently associated with the time of recurrence, and the risk ratios were 0.424, 1.100, 1.084 and 1.268, respectively. Therefore, in male patients with a larger maximum tumor diameter, positivity for Ki-67 and a higher T2 signal ratio, desmoid-type fibromatosis was more likely to recur after surgery.

Clinical validation of three-dimensional ultrasound for abdominal aortic aneurysm.

OBJECTIVE: Three-dimensional ultrasound (3D-US) examination is a relatively new modality that can be used for abdominal aortic aneurysm (AAA) surveillance, and may offer improved reproducibility over conventional two-dimensional ultrasound (2D-US) examination. The aim of this study was to evaluate the interoperator reproducibility of maximum anterior-to-posterior diameter by nonphysician ultrasound technicians in a typical vascular laboratory setting, on patients with infrarenal AAAs using 3D-US and 2D-US examination. METHODS: A total of 134 consecutive patients with asymptomatic infrarenal AAAs were screened. Of the 134 patients, 28 (21%) were screen failures. From the remaining 106 patients, 3 (2.8%) had missing data and 13 (12.3%) had technically unacceptable image quality. As a result, 90 patients were included for final analysis. Ultrasound image acquisitions were performed during the single visit. The 2D-US images were evaluated at the time of examination by the respective ultrasound technicians who acquired them. All 3D-US images were evaluated offline by both ultrasound technicians after a wash-out period of at least 6 weeks. RESULTS: Excellent interoperator reproducibility was observed for measuring maximum diameter using 3D-US (intraclass correlation coefficient, 0.97), and good agreement among ultrasound technicians (mean difference, -0.08 mm; limits of agreement, -3.17; 3.00 mm). When using 3D-US examination, 74 of the 90 patients (82%) were estimated within 2 mm of interoperator variability. Of 90 patients, 52 (58%) were estimated to be within the same variability by 2D-US examination. Estimating AAA diameter using 3D-US was superior to 2D-US with respect to interoperator reproducibility. CONCLUSIONS: Both 3D-US and 2D-US examination demonstrated good reproducibility among two vascular ultrasound technicians with superior agreement from 3D-US examination. The present results support the broader use of 3D-US in standard AAA surveillance programs.

The maximum diameter of cervical lymph node was not a prognostic factor for local-regional advanced nasopharyngeal carcinoma treated with intensity modified radiotherapy.

BACKGROUND: Cervical lymph node metastasis was an important prognostic factor. However, the prognosis of the maximum diameter of cervical lymph nodes before treatment has always been controversial. The aim of this study was to analyze the relationship between treatment outcomes and the maximum diameter of lymph nodes (Dmax) in loco-regional advanced nasopharyngeal carcinoma (NPC) after intensity modified radiotherapy. METHODS: From Jan. 2012 to Dec. 2017, 163 patients with locally advanced NPC treated with intensity modified radiotherapy were retrospectively analyzed. The T-stage distribution was 6.7% in T1, 23.3% in T2, 38.7% in T3, and 31.3% in T4. The N-classifications were 6.1% in N0, 23.3% in N1, 47.9% in N2, and 22.7% in N3. TNM stages were III 51.5% and IVa 48.5%. All patients received intensity modified radiotherapy to the nasopharynx and neck. The dose was 66-70.4 Gy, 2-2.2 Gy per fraction over 6-7 weeks to the primary tumor and lymph nodes and 54-60 Gy to clinical target volumes (CTVs). One hundred fifty patients were received induction chemotherapy and/or concurrent chemotherapy. The maximum diameter of the lymph node is measured on the axial or coronal MRI image. RESULTS: The median follow-up time was 31 months (range, 6.1-79.3 months). Six cases developed neck recurrence and 9 cases developed nasopharynx recurrence. The lymph nodes diameter was 0-12 cm, median 2.9 cm. Three-year overall survival (OS) rate was 77.8%. Three-year local failure-free rate (L-FFR), distant failure-free rate (D-FFR) and disease-free survival (DFS) rate were 88.1%, 77.6% and 63.9% respectively. Multivariate analysis showed Dmax was not a prognostic factor for OS, L-FFR, D-FFR, DFS. Both uni- and multivariate analyses demonstrated that N-classification and age is the significant prognostic factor for predicting OS while the maximum diameter of lymph nodes, T-classification, N-classification and AJCC-classification are the significant prognostic factor for predicting OS in univariate analyses in local-regional advanced NPC. CONCLUSIONS: The maximum diameter of the lymph nodes was not a prognostic factor for local-regional advanced NPC treated with intensity modulated radiotherapy.

Serial Follow-Up Evaluation With Computed Tomography After Conservative Medical Treatment in Patients With Symptomatic Spontaneous Isolated Superior Mesenteric Artery Dissection.

OBJECTIVE: There is no detailed information available about trend in the morphological change after conservative medical treatment in patients with symptomatic spontaneous isolated superior mesenteric artery dissection (SISMAD). METHODS: We enrolled 27 consecutive patients with symptomatic SISMAD who underwent conservative medical treatment between 2006 and 2015. The long-term prognosis, natural history, and serial follow-up computed tomography (CT) findings of risk factors of rupture such as arterial diameter and false lumen enhancement were retrospectively assessed. RESULTS: Spontaneous isolated superior mesenteric artery dissection usually developed in middle-aged men around 50 years old who had a history of smoking. Follow-up CT was performed at 1 to 6 months, 7 to 12 months, and after 12 months. Superior mesenteric artery (SMA) maximum diameter was 10.3 mm (quartile 9.5-11.3) on initial CT and expanded in 47.1% patients during 1- to 6-month follow-up, which decreased over time ( P < .001 at 7- to 12-month follow-up, P = .001 after 12-month follow-up). On the other hand, false lumen enhancements were revealed in 9 (33.3%) patients on initial CT. The size of false lumen enhancement was expanded in the longest diameter in 35.3% patients and in shortest diameter in 29.4% during 1- to 6-month follow-up. However, the size of false lumen decreased in all patients after 12-month follow-up. All patients were alive without arterial aneurysm rupture and hospital readmission during the median of 523 days (170-799) study period. CONCLUSION: We demonstrated that both SMA maximum diameter and false lumen enhancement were transiently expanded in some patients during 6-month follow-up, but no longer expanded after 12-month follow-up. Patients with symptomatic SISMAD could be treated medically with scheduled careful follow-up CT evaluations.

Continuous measurement of aortic dimensions in Turner syndrome: a cardiovascular magnetic resonance study.

BACKGROUND: Severity of thoracic aortic disease in Turner syndrome (TS) patients is currently described through measures of aorta size and geometry at discrete locations. The objective of this study is to develop an improved measurement tool that quantifies changes in size and geometry over time, continuously along the length of the thoracic aorta. METHODS: Cardiovascular magnetic resonance (CMR) scans for 15 TS patients [41 ± 9 years (mean age ± standard deviation (SD))] were acquired over a 10-year period and compared with ten healthy gender and age-matched controls. Three-dimensional aortic geometries were reconstructed, smoothed and clipped, which was followed by identification of centerlines and planes normal to the centerlines. Geometric variables, including maximum diameter and cross-sectional area, were evaluated continuously along the thoracic aorta. Distance maps were computed for TS and compared to the corresponding maps for controls, to highlight any asymmetry and dimensional differences between diseased and normal aortae. Furthermore, a registration scheme was proposed to estimate localized changes in aorta geometry between visits. The estimated maximum diameter from the continuous method was then compared with corresponding manual measurements at 7 discrete locations for each visit and for changes between visits. RESULTS: Manual measures at the seven positions and the corresponding continuous measurements of maximum diameter for all visits considered, correlated highly (R-value = 0.77, P < 0.01). There was good agreement between manual and continuous measurement methods for visit-to-visit changes in maximum diameter. The continuous method was less sensitive to inter-user variability [0.2 ± 2.3 mm (mean difference in diameters ± SD)] and choice of smoothing software [0.3 ± 1.3 mm]. Aortic diameters were larger in TS than controls in the ascending [TS: 13.4 ± 2.1 mm (mean distance ± SD), Controls: 12.6 ± 1 mm] and descending [TS: 10.2 ± 1.3 mm (mean distance ± SD), Controls: 9.5 ± 0.9 mm] thoracic aorta as observed from the distance maps. CONCLUSIONS: An automated methodology is presented that enables rapid and precise three-dimensional measurement of thoracic aortic geometry, which can serve as an improved tool to define disease severity and monitor disease progression. TRIAL REGISTRATION: ClinicalTrials.gov Identifier - NCT01678274 . Registered - 08.30.2012.

Reliability of the Size Evaluation Method for Meningiomas: Maximum Diameter, ABC/2 Formula, and Planimetry Method.

BACKGROUND: To evaluate the accuracy of tumor size by maximum diameter, ABC/2 formula, and planimetry method using thick-slice and thin-slice magnetic resonance imaging (MRI). METHODS: Maximum diameter and tumor volume calculated using ABC/2 formula (V1) and planimetry method with thick-slice MRI (V2) and thin-slice MRI (V3) were examined in 83 meningiomas. Form factor (FF) analysis was performed to assess irregularity of the tumor. V3 values were considered as real tumor volumes. The accuracy of V1 and V2 was evaluated using ratio and difference from V3. Meningiomas were categorized by tumor locations: skull base (anterior, middle, and posterior) and non-skull base (calvaria and other sites). RESULTS: Correlation between maximum diameter and V3 was statistically significant (r = 0.91), but the error was significant in tumors with longer maximum diameters. Correlation between V1 and V3 was significant (r = 0.97). However, V1 tended to be larger in middle skull base meningiomas or in tumors with low FF values (R2 = 0.21). V2 represented relatively accurate volumes in both groups except in the case of small meningiomas. When tumors were demonstrated within 3 fractions on thick-slice MRI, the ratio of V2 to V3 showed significant variability. CONCLUSIONS: Using the ABC/2 formula, the volume of meningiomas in the middle skull base or meningiomas with low FF value might be calculated larger than the real tumor volume. The planimetry method with thick-slice MRI demonstrated relatively accurate volumes if the tumor was fractionated in >4 slices.

Advances in determining abdominal aortic aneurysm size and growth.

Abdominal aortic aneurysm is a common pathology in the aging population of the developed world which carries a significant mortality in excess of 80% in case of rupture. Aneurysmal disease probably represents the only surgical condition in which size is such a critical determinant of the need for intervention and therefore the ability to accurately and reproducibly record aneurysm size and growth over time is of outmost importance. In the same time that imaging techniques may be limited by intra- and inter-observer variability and there may be inconsistencies due to different modalities [ultrasound, computed tomography (CT)], rapid technologic advancement have taken aortic imaging to the next level. Digital imaging, multi-detector scanners, thin slice CT and most- importantly the ability to perform 3-dimensional reconstruction and image post-processing have currently become widely available rendering most of the imaging modalities used in the past out of date. The aim of the current article is to report on various imaging methods and current state of the art techniques used to record aneurysm size and growth. Moreover we aim to emphasize on the future research directions and report on techniques which probably will be widely used and incorporated in clinical practice in the near future.

Assessment of image-derived risk factors for natural course of unruptured cerebral aneurysms.

OBJECTIVE: The goal of this prospective longitudinal study was to test whether image-derived metrics can differentiate unruptured aneurysms that will become unstable (grow and/or rupture) from those that will remain stable. METHODS: One hundred seventy-eight patients harboring 198 unruptured cerebral aneurysms for whom clinical observation and follow-up with imaging surveillance was recommended at 4 clinical centers were prospectively recruited into this study. Imaging data (predominantly CT angiography) at initial presentation was recorded. Computational geometry was used to estimate numerous metrics of aneurysm morphology that described the size and shape of the aneurysm. The nonlinear, finite element method was used to estimate uniform pressure-induced peak wall tension. Computational fluid dynamics was used to estimate blood flow metrics. The median follow-up period was 645 days. Longitudinal outcome data on these aneurysm patients-whether their aneurysms grew or ruptured (the unstable group) or remained unchanged (the stable group)-was documented based on follow-up at 4 years after the beginning of recruitment. RESULTS: Twenty aneurysms (10.1%) grew, but none ruptured. One hundred forty-nine aneurysms (75.3%) remained stable and 29 (14.6%) were lost to follow-up. None of the metrics-including aneurysm size, nonsphericity index, peak wall tension, and low shear stress area-differentiated the stable from unstable groups with statistical significance. CONCLUSIONS: The findings in this highly selected group do not support the hypothesis that image-derived metrics can predict aneurysm growth in patients who have been selected for observation and imaging surveillance. If aneurysm shape is a significant determinant of invasive versus expectant management, selection bias is a key limitation of this study.

Left atrial function and maximum volume as determined by MDCT are independently associated with atrial fibrillation.

RATIONALE AND OBJECTIVES: To assess whether left atrial (LA) volume, function, and diameter as determined by multidetector computed tomography (MDCT) are associated with the presence and chronicity of atrial fibrillation (AF). MATERIALS AND METHODS: A total of 232 subjects, 156 with AF (43 with chronic and 113 with paroxysmal) and 76 normal subjects, formed the study population. AF subjects underwent MDCT of the pulmonary veins and LA, and normal subjects underwent coronary computed tomography (CT), on which LA volume, function, and diameter were measured. Associations between each MDCT LA parameter and presence and chronicity of AF were assessed using logistic regression analysis. RESULTS: The indexed LA maximum volume (odds ratio [OR]=2.42; 95% confidence interval [CI], 1.43-4.08; P=.0009) was significantly associated with chronicity and presence of AF (OR=1.06; 95% CI, 1.03-1.10; P=.0003) after adjustment for traditional risk factors. The LA function was associated with presence of AF (OR=0.93; 95% CI, 0.89-0.97; P=.0005), but not with AF chronicity (OR=1.12; 95% CI, 0.93-1.33; P=.21). CONCLUSIONS: Decreased LA function is associated with presence of AF, and increased LA maximum volume is associated with presence and chronicity of AF, independent of traditional risk factors.

Prognostic value of maximum diameter in axial plane of primary tumor on MRI in nasopharyngeal carcinoma / 中华放射肿瘤学杂志

Objective To investigate the prognostic value of maximum diameter in axial plane of primary tumor (MDAPPT) on MRI in nasopharyngeal carcinoma (NPC).Methods From 2005 to 2007,333 patients with newly diagnosed and biopsy-proven NPC without distant metastasis,who underwent MRI scans of the nasopharynx and neck,were included in our study.MDAPPT was measured on MRI.The univariate analysis with the log-rank test and multivariate analysis with the Cox proportional hazards model were used to analyze the relationship between MDAPPT and prognosis.Results The median values of MDAPPT in patients with T1,T2,T3,and T4 NPC were 21.2,30.0,38.0,and 52.3 mm,respectively.For all patients with a MDAPPT of ≤30 mm,＞ 30-50 mm,and ＞ 50 mm,the 5-year overall survival (OS) rates were 81.3％,70.1％,and 51.5％,respectively (P =0.000) ; the 5-year progression-free survival (PFS) rates were 81.3％,70.0％,and 48.9％,respectively (P =0.000) ;the 5-year distant metastasisfree survival (DMFS) rates were 85.5 ％,86.5 ％,and 67.2 ％,respectively (P =0.000) ; the 5-year local relapse-free survival (LRFS) rates were 97.7％,91.5％,and 83.3％,respectively (P =0.013).The multivariate analysis showed that MDAPPT was a prognostic factor for PFS and DMFS.For the T3-T4 patients with a MDAPPT of ≤50 mm and ＞50 mm,the 5-year OS rates were 69.4％ and 52.2％ (P =0.004),the 5-year PFS rates were 68.0％ and 49.6％ (P =0.001),and the 5-year DMFS rates were 84.0％ and 66.8％ (P=0.001).In the patients with a MDAPPT ≤30 mm,the 5-year LRFS rates for those with T1,T2,T3,and T4 NPC were 10 0 ％,9 5.8 ％,9 6.3 ％,and 10 0 ％,respectively (P =0.6 4 3).Conclusions MDAPPT is a prognostic factor for PFS and DMFS in NPC,and it is an important prognostic factor in patients with T3-T4 NPC.In the NPC patients with a small MDAPPT,local control rate varies little in different T stages.

Comparison of two- and three-dimensional transthoracic echocardiography for measurement of aortic annulus diameter in children.

BACKGROUND: Accurate evaluation of aortic root geometry is necessary in congenital aortic valve lesions in children, to guide surgical or angiographical intervention. AIM: To compare aortic annulus diameters measured by two- and three-dimensional transthoracic echocardiography (2D- and 3D-TTE), to determine the feasibility and reproducibility of 3D imaging and assess the dynamic changes during the cardiac cycle. METHODS: Thirty children without heart disease were prospectively included. Two orthogonal aortic annulus diameters were measured offline using multiplanar reconstruction in diastole and in systole and were compared with the measurement of the aortic annulus diameter by 2D-TTE. RESULTS: Mean age was 11±3.6 years. Feasibility of 3D imaging was 100%. The coefficients of intra- and interobserver variability were 3.5% and 6%, respectively. The 2D mean diameter was significantly smaller than the 3D maximum diameter in systole (1.94 vs. 2.01mm; p=0.005). 2D and 3D measurements were well correlated (p<0.0001). The maximum and minimum diameters in 3D were significantly different both in systole and in diastole (p<0.001) underlining an aortic annulus eccentricity. The mean aortic annulus diameters were not significantly different between systole and diastole, with important individual variability during the cardiac cycle. CONCLUSION: This study demonstrated the feasibility and reproducibility of 3D-TTE for the assessment of the aortic annulus diameter in a normal paediatric population. Because of an underestimation of the maximum diameter by 2D-TTE and the asymmetry of the aortic annulus, 3D measurements could be important before percutaneous aortic valvuloplasty or surgical replacement.

Método para determinar o diâmetro máximo de corte em florestas tropicais utilizando-se o gráfico "Uplot-Dap"

This research presents a method for determination of the maximum diameter of cut in tropical forests being used the denominated graphic construction of "Uplot-Dap". The main objective consisted on detecting the existence and location of a possible maximum diameter in function of the biological balance of the species in a climax forest. To test the graphic method they were used 28320 DBH (cm) outside bark coming from 15 blocks of 96 hectares is of the National Forest of Tapajós, Belterra, Pará, Brazil. The method that uses technique of visual analysis of data as a way of interpretation of the dispersion of the diameters, was shown quite flexible and essentially practical. The graphs were built considering a width of diameter class of 10 cm adopted as reference value. Through this method it was possible to fasten the DBH=95 cm as an indicator of the maximum diameter of exploitability to be adopted in the 1st intervention as reference value in the cut operations for this forest type. Mean while this point can vary from forest to forest and its clearness depends on the forest type and its structural condition. The largest contribution of the graphic method consisted on respecting the properties of the diameter classes in natural forests that for biological reasons or sucessional estate, express its diameter distribution as a function of rare, null or probabilistics events. The efficiency of the method bases on its capacity of controlling the variation of the data so that the analysis are more consistent with the physical and biological factors that characterize the dynamics of natural forests.

A presente pesquisa apresenta um método de determinação do diâmetro máximo de corte para florestas tropicais utilizando-se a construção gráfica denominada de "Uplot-Dap". O objetivo da pesquisa foi detectar a existência e locação de um possível diâmetro máximo em função do equilíbrio biológico das espécies em uma floresta clímax, utilizando-se o método gráfico "Uplot-Dap". Para testar o método gráfico foram utilizados 28320 DAP com casca de árvores procedentes de 15 blocos de 96 ha da Floresta Nacional do Tapajós, Belterra, Pará. Os gráficos foram construídos considerando uma amplitude de classe diamétrica de 10 cm adotada como valor de referência. O método "Uplot-Dap" que utiliza técnica de análise visual de dados como forma de interpretação da dispersão dos diâmetros, mostrou-se bastante flexível e essencialmente prático. Através do método foi possível fixar o DAP=95 cm como um indicador do diâmetro máximo de explorabilidade a ser adotado na primeira intervenção como valor de referência nas operações de corte para esse tipo de floresta. Todavia, esse ponto pode variar de floresta para floresta e sua nitidez depende do tipo de floresta e suas condições estruturais. A maior contribuição do método gráfico consistiu em respeitar as propriedades das classes diamétricas em florestas naturais que por razões biológicas ou estágio sucessional, expressem a sua distribuição diamétrica como uma função de eventos raros, nulos ou probabilísticos. A eficiência do método baseia-se na sua capacidade de controlar a variação dos dados de modo que as análises sejam mais consistentes com os fatores físicos e biológicos que caracterizam a dinâmica de florestas naturais.