Enhancing component on CT to predict malignancy in cystic renal masses and interobserver agreement of different CT features

OBJECTIVE: The objective of our study was to determine the CT features of complex cystic renal masses that are the most predictive of malignancy and to assess interobserver variability when interpreting these features. MATERIALS AND METHODS: Two radiologists blinded to pathology results retrospectively reviewed CT scans of 36 consecutive cystic renal masses in 30 patients (19 men and 11 women; age range, 28-76 years; mean age, 59 +/- 13 years) who had undergone surgery. The study population included only masses with a cystic component on gross pathology and imaging. All patients underwent contrast-enhanced CT. The reviewers recorded the CT features of each cystic mass, including the presence of enhancing components. Accuracy values and odds ratio to predict malignancy were calculated for each CT feature. Weighted kappa was used to measure interobserver agreement. RESULTS: There were 21 cystic renal cell cancers and 11 benign cystic lesions. All cystic renal cell carcinomas showed an enhancing septal or nodular component. The mean sensitivity and specificity of the two reviewers in predicting malignancy for the presence of septal enhancement were 83% (95% confidence interval [CI], 65-93%) and 82% (95% CI, 56-94%); for nodular enhancement, 67% (95% CI, 49-81%) and 96% (95% CI, 75-99%); and for either septal or nodular enhancement, 100% (95% CI, 86-100%) and 86% (95% CI, 67-95%), respectively. The interobserver agreements for septal and nodular enhancement were good (kappa = 0.67) and moderate (kappa = 0.57), respectively. CONCLUSION: The presence of either nodular or septal enhancement shows the highest sensitivity for predicting malignancy with moderate to good interobserver agreement.     

Acute diverticulitis of the cecum and ascending colon: the value of thin-section helical CT findings in excluding colonic carcinoma

OBJECTIVE: The purpose of this study was to assess the value of characteristic thin-section helical CT findings of acute diverticulitis involving the cecum and ascending colon in excluding colonic carcinoma. MATERIALS AND METHODS: Thin-section helical CT scans (5-mm collimation) of 19 consecutive patients with proven diverticulitis and 21 consecutive patients with surgically proven carcinoma involving the cecum and ascending colon were reviewed retrospectively. Two radiologists independently analyzed these parameters: degree of pericolic infiltration, mesenteric fluid, vascular engorgement, arrowhead-shaped wall thickening, air-filled diverticula, inflamed diverticula, and preserved enhancement pattern of involved colonic wall. Inter-observer agreement was assessed with a kappa statistical analysis, and the features that most distinguished diverticulitis from colonic carcinoma were selected with a stepwise logistic-regression analysis. RESULTS: The two CT findings of right-sided colonic diverticulitis that most distinguished it from colonic carcinoma were inflamed diverticula and the preservation of an enhancement pattern of the involved colonic wall. Excellent interobserver agreement (kappa > 0.60) was obtained for both findings. Inflamed diverticula (kappa = 0.80) had a mean sensitivity, specificity, and accuracy for diverticulitis of 86.8%, 92.9%, and 90.0%, respectively, in differentiating right-sided colonic diverticulitis from colonic carcinoma. Preserved wall enhancement pattern (kappa = 0.70) had a mean sensitivity, specificity, and accuracy of 89.5%, 95.3%, and 92.5%, respectively. CONCLUSION: On thin-section helical CT, an inflamed diverticula and a preserved enhancement pattern of the thickened colonic wall were the two most statistically significant CT findings of acute diverticulitis involving the cecum and ascending colon that distinguished diverticulitis from colonic carcinoma.     

Sensitivity and interrater agreement of CT and diffusion-weighted MR imaging in hyperacute stroke

BACKGROUND AND PURPOSE: Previous acute stroke studies found diffusion-weighted (DW) imaging superior to CT for detection of early ischemic signs (EIS). However, these findings were confounded by a large time interval in favor of DW imaging. We compared DW images and CT scans obtained with a short time delay in patients with acute stroke to define the sensitivity and interrater agreement of both imaging techniques. METHODS: CT scans and DW images were obtained within 6 hours of symptom onset in 46 patients with acute stroke. Three neuroradiologists and three neurologists reviewed the images for EIS in five regions of the middle cerebral artery (MCA) territory and estimated the extent of EIS (< or > one-third of the MCA territory). RESULTS: The mean delay between imaging with both modalities was 24.5 minutes (range, 10-41 minutes). Forty-five of 46 patients had an ischemic stroke. EIS were seen on 33 of 45 CT scans (73% sensitivity; 95% confidence interval [CI]: 58-85%) and on 42 of 45 DW images (93% sensitivity; 94% CI: 82-99%). Interrater agreement was moderate (kappa = 0.57) for CT and excellent (kappa = 0.85) for DW imaging. CT studies had a moderate interrater agreement for estimation of EIS greater than one-third of the MCA territory (kappa = 0.40), whereas DW imaging showed good results (kappa = 0.68). Sensitivity for detection of greater than one-third of the MCA territory was equally poor (57%, 95% CI: 29-82%) for both CT and DW imaging. CONCLUSION: DW imaging helped identify EIS with higher sensitivity than that of CT. The interrater variability of the one-third rule was high for CT, and thus the clinical applicability of CT is limited. Our results support the application of stroke MR imaging for the treatment of patients with acute stroke.     

Spiral CT colonography: reader agreement and diagnostic performance with two- and three-dimensional image-display techniques

PURPOSE: To assess the diagnostic performance and reader agreement with two-dimensional (2D) and three-dimensional (3D) display techniques for detecting colorectal polyps with spiral computed tomographic (CT) colonography. MATERIALS AND METHODS: A test set of 30 colonic segments was developed from spiral CT colonographic studies (12 with polyps and 18 without). The 12 segments with polyps contained 22 lesions (11 polyps <10 mm, 11 polyps or cancers >/=10 mm), with all findings verified with colonoscopy. Three specific 2D and 3D image-display techniques were tested. Three experienced abdominal radiologists independently analyzed each test case and were retested 6 weeks later. RESULTS: The results of readings 1 and 2 were similar for all image-display techniques among the readers. Pooled segment results were sensitivity of 89%-92% and specificity of 72%-83%. Pooled polyp size results for sensitivity and positive predictive value were 77%-86% and 74%-86% (all polyps, n = 22), 91%-100% and 85%-100% (polyps or cancers >10 mm, n = 11), and 61%-73% and 61%-80% (polyps 5-9 mm, n = 11), respectively. Overall intraobserver agreement was good for the three display techniques (kappa, 0.60-1.00); however, interobserver agreement for 2D multiplanar reformation was lower (kappa, 0.53-0.80). CONCLUSION: Among experienced abdominal radiologists, similar diagnostic performance in polyp detection was found among 2D multiplanar reformation and 3D display techniques, although individual cases showed improved characterization with 3D display techniques. Evaluation of reader agreement demonstrated good intraobserver agreement, with variable interobserver agreement.     

Comparative assessment of CT and sonographic techniques for appendiceal imaging

OBJECTIVE: We performed a comparative assessment of CT and sonographic techniques used to assess appendicitis. MATERIALS AND METHODS: One hundred patients with clinically suspected acute appendicitis were examined with sonography, unenhanced focused appendiceal CT, complete abdominopelvic CT using IV contrast material, focused appendiceal CT with colonic contrast material, and repeated sonography with colonic contrast material. Each sonogram was videotaped for subsequent interpretation by three radiologists and two sonographers. The mean sensitivity, specificity, positive and negative predictive values, inter- and intraobserver variability, and diagnostic confidence scores of all observers were used for comparative performance assessments. The three CT examinations were filmed and interpreted separately by four radiologists. Patient discomfort was assessed on a 10-point scale for each radiologic study. Diagnoses were confirmed by pathologic evaluation of resected appendixes or clinical follow-up for a minimum of 3 months after presentation. RESULTS: Twenty-four of the 100 patients had positive findings for acute appendicitis. Both sonographic techniques had high specificity (85-89%) and comparable accuracy (73-75%) but low sensitivity (33-35%) and inter- and intraobserver variability (kappa = 0.15-0.20 and 0.39-0.42, respectively). Unenhanced focused appendiceal CT, abdominopelvic CT, and focused appendiceal CT with colonic contrast material all significantly outperformed sonography (p <0.0001), with sensitivities of 78%, 72%, and 80%; specificities of 86%, 91%, and 87%; and accuracies of 84%, 87%, and 85%, respectively. Abdominopelvic CT gave the greatest confidence in cases with negative findings (p = 0.001), and focused appendiceal CT with colonic contrast material gave the greatest confidence for cases with positive findings (p = 0.02). In terms of inter- and intraobserver variability, focused appendiceal CT with colonic contrast material yielded the highest, and unenhanced focused appendiceal CT the lowest, agreement (interobserver kappa = 0.45 vs. 0.36 and intraobserver kappa = 0.85 vs. 0.76, respectively) (p <0.05). Colonic contrast material was unsuccessfully advanced into the cecum in 18% of patients and leaked in another 24%. Patient discomfort was greatest with focused appendiceal CT using colonic contrast material and least with unenhanced focused appendiceal CT (p <0.05). CONCLUSION: A standard abdominopelvic CT scan is recommended as the initial examination for appendicitis in adult patients. However, focused appendiceal CT with colonic contrast material material should be used as a problem-solving technique in difficult cases.     

Interobserver agreement in assessing early CT signs of middle cerebral artery infarction.

PURPOSETo assess the reliability of detecting signs of hemispheric infarction on CT scans obtained within 6 hours of the onset of symptoms.METHODSA neuroradiologist selected 12 normal and 33 abnormal CT studies showing the hyperdense middle cerebral artery sign (HMCAS) (n = 10), brain swelling (n = 22), and parenchymal hypodensity (n = 33) from two series of 750 patients with recent onset of middle cerebral artery stroke. These selections served as the reference source for a nonblinded analysis of the initial and follow-up CT scans. Six neuroradiologists then reviewed the CT scans twice, first blinded then not blinded to clinical symptoms. They assessed the signs of infarction for each hemisphere separately and estimated the volume of abnormal parenchymal hypodensity in increments of 20% within the territory of the middle cerebral artery.RESULTSUnblinding the reviewers did not change interobserver agreement significantly. The chance adjusted agreement was moderate to substantial: kappa = .62 (95% confidence interval [CI], .46 to .78) and kappa = .57 (95% CI, .33 to .81) for the HMCAS of the right and left hemisphere, respectively; kappa = .59 (95% CI, .47 to .71) and kappa = .56 (95% CI, .38 to .74) for focal brain swelling of the right and left hemisphere, respectively; and kappa = .58 (95% CI, .50 to .66) and kappa = .55 (95% CI, .32 to .67) for parenchymal hypodensity of the right and left hemisphere, respectively. Weighted kappa was .65 and .57 for the estimation of the hypodense tissue volume in the right and left hemisphere, respectively. Agreement with the reference source ranged from 73% to 93% for all variables and both hemispheres.CONCLUSIONEven with no clinical information, neuroradiologists can assess subtle CT signs of cerebral infarction within the first 6 hours of symptom onset with moderate to substantial interobserver agreement.     

The role of multidetector CT in local staging and evaluation of retroperitoneal surgical margin involvement in colon cancer

PURPOSE

We aimed to evaluate preoperative T and N staging and retroperitoneal surgical margin (RSM) involvement in colon cancer using multidetector computed tomography (MDCT).

METHODS

In this retrospective study, preoperative MDCTs of 141 patients with colon adenocarcinoma were evaluated in terms of T and N staging and retroperitoneal surgical margin involvement by two observers. Results were compared with histopathology.

RESULTS

In determining extramural invasion, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of MDCT were 81%, 50%, 95%, 26%, and 81% for observer 1 and 87%, 75%, 97%, 27%, and 84% for observer 2, respectively. Moderate interobserver agreement was observed (κ=0.425). In determining T stage of the tumor, accuracy of MDCT was 55% for observer 1 and 51% for observer 2. In the detection of lymph node metastasis, sensitivity, specificity, PPV, NPV, and accuracy of MDCT were 84%, 46%, 60%, 74% and 64% for observer 1 and 84%, 56%, 65%, 78%, and 70% for observer 2, respectively. Interobserver agreement was substantial (κ=0.650). RSM was involved in six cases (4.7%). When only retroperitoneal colon segments were considered, 1.6% of subjects demonstrated RSM involvement. Four of the six RSM-positive tumors were located on sigmoid colon and one tumor was on transverse colon and caecum. Considering all colon tumors, in the detection of RSM involvement, sensitivity and specificity of MDCT were 33% and 81% for observer 1 and 50% and 80% for observer 2. Interobserver agreement was moderate (κ=0.518).

CONCLUSION

MDCT is a promising technique with moderate interobserver agreement in detection of extramural invasion, lymph node metastases, and RSM involvement in colon carcinomas.With the advent of technological improvements, computed tomography (CT) became one of the important diagnostic tools in the evaluation of local characteristics, preoperative staging, and prognostic factors of colon cancers (1). CT is recommended by EURECCA consensus group for staging of colon cancers (2). Extramural invasion (EMI) is an important factor affecting the prognosis in patients with colon cancer (3). Preoperative CT can detect EMI in colon cancers with high sensitivity (4). In addition, CT-based T staging can be used to stratify patients into good and poor prognosis (4, 5).Correlation between local recurrence and circumferential resection margin involvement in rectal cancer suggests the importance of retroperitoneal surgical margin (RSM) involvement in retroperitoneal ascending and descending colon tumors. RSM involvement is defined as less than 1 mm distance between RSM and primary adenocarcinoma or metastatic retroperitoneal lymph node in descending and ascending colon cancers (6). Studies suggest that RSM positivity may be a predictor and an independent prognostic indicator showing local recurrence in colon cancers (7).Classical colon cancer treatment is based on histopathologic prognostic factors in the resected specimen (1). However, at the present time, with the development of more effective chemotherapeutic agents and higher accuracy in preoperative staging, neoadjuvant treatments are preferred in patients with high-risk colon cancer (2, 8). Preoperative radiologic assessment of EMI and RSM positivity can decrease the local recurrence risk through timely recommendation of neoadjuvant chemotherapy which would lead to regression of metastatic lymph nodes, retroperitoneal extension, and tumor burden (6–8). Since severe adverse effects can be observed, neoadjuvant treatment should be administered to patients who would benefit the most from it. The aim of this study was to evaluate preoperative T and N staging and RSM involvement in colon cancer using multidetector CT (MDCT) and compare them with histopathology results.     

Baseline metabolic tumor burden on FDG PET/CT scans predicts outcome in advanced NSCLC patients treated with immune checkpoint inhibitors

We aimed to evaluate if imaging biomarkers on FDG PET are associated with clinical outcomes in patients with advanced non-small cell lung cancer (NSCLC) treated with immune checkpoint inhibitors (ICIs). In this retrospective monocentric study, we included 109 patients with advanced NSCLC who underwent baseline FDG PET/CT before ICI initiation between July 2013 and September 2018. Clinical, biological (including dNLR = neutrophils/[leukocytes minus neutrophils]), pathological and PET parameters (tumor SUVmax, total metabolic tumor volume [TMTV]) were evaluated. A multivariate prediction model was developed using Cox models for progression-free survival (PFS) and overall survival (OS). The association between biomarkers on FDG PET/CT and disease clinical benefit (DCB) was tested using logistic regression. Eighty patients were eligible. Median follow-up was 11.6 months (95%CI 7.7–15.5). Sixty-four and 52 patients experienced progression and death, respectively. DCB was 40%. In multivariate analyses, TMTV > 75 cm3 and dNLR > 3 were associated with shorter OS (HR 2.5, 95%CI 1.3–4.7 and HR 3.3, 95%CI 1.6–6.4) and absence of DCB (OR 0.3, 95%CI 0.1–0.9 and OR 0.4, 95%CI 0.2–0.9). Unlike TMTV, dNLR was a significant prognostic factor for PFS (HR 1.9, 95%CI 1.1–3.3) along with anemia (HR 1.9, 95%CI 1.2–3.8). No association was observed between tumor SUVmax and PFS or OS. Baseline tumor burden (TMTV) on FDG PET/CT scans and inflammatory status (dNLR) were associated with poor OS and absence of DCB for ICI treatment in advanced NSCLC patients, unlike tumor SUVmax, and may be used together to improve the selection of appropriate candidates.     

基于CT平扫纹理分析的影像组学预测肾透明细胞癌WHO/ISUP分级的初步研究

目的:探讨基于肾脏CT平扫图像纹理分析的影像组学模型在预测肾透明细胞癌（ccRCC）WHO/国际泌尿病理学会（ISUP）病理分级中的价值。方法:回顾性分析2016年12月至2019年5月中国科学院大学附属肿瘤医院经手术病理证实且有明确病理分级的90例ccRCC患者,按照7∶3的比例将所有患者随机分为训练组（63例）及测...     

Graded compression ultrasonography and computed tomography in acute colonic diverticulitis: Meta-analysis of test accuracy

The purpose was to investigate the diagnostic accuracy of graded compression ultrasonography (US) and computed tomography (CT) in diagnosing acute colonic diverticulitis (ACD) in suspected patients. We performed a systematic review and meta-analysis of the accuracy of CT and US in diagnosing ACD. Study quality was assessed with the QUADAS tool. Summary estimates of sensitivity and specificity were calculated using a bivariate random effects model. Six US studies evaluated 630 patients, and eight CT studies evaluated 684 patients. Overall, their quality was moderate. We did not identify meaningful sources of heterogeneity in the study results. Summary sensitivity estimates were 92% (95% CI: 80%-97%) for US versus 94% (95%CI: 87%-97%) for CT (p = 0.65). Summary specificity estimates were 90% (95%CI: 82%-95%) for US versus 99% (95%CI: 90%-100%) for CT (p = 0.07). For the identification of alternative diseases sensitivity ranged between 33% and 78% for US and between 50% and 100% for CT. The currently best available evidence shows no statistically significant difference in accuracy of US and CT in diagnosing ACD. Therefore, both US and CT can be used as initial diagnostic tool until new evidence is brought forward. However, CT is more likely to identify alternative diseases. The Dutch Organisation for Health Research and Development, Health Care Efficiency Research programme, funded the study (ZonMw, grant number 945-04-308).     

基于薄层CT的影像组学和形态学特征联合模型在预测磨玻璃样肺腺癌浸润程度的价值

目的 探讨基于薄层CT的影像组学和形态学特征联合模型在预测磨玻璃样肺腺癌中的原位癌(AIS)、微浸润腺癌(MIA)、浸润性腺癌(IAC)的价值.方法 回顾性分析2018年6月至2021月3月经病理证实的327例肺腺癌患者(335个病灶)术前肺部CT检查图像,随机选取201个为训练集,134个为测试集.肺腺癌参照病理金标...     

后循环急性缺血性脑卒中患者经机械取栓完全复流后不良预后的影响因素分析

目的探索后循环急性缺血性脑卒中（PCS）患者经机械取栓并完全恢复前向血流后部分患者临床预后仍然不佳的影响因素。 方法连续纳入2017年1月至2020年9月于我院接受机械取栓治疗的PCS患者并进行回顾性分析。闭塞血管完全恢复前向血流定义为改良脑梗死溶栓血流分级（mTICI）达3级。90 d改良Rankin评分（mRS）> 2分则被定义为预后不良。将患者基线资料、治疗相关指标纳入多因素分析,并采用受试者工作特征曲线（ROC）来确定最佳界值。 结果共纳入39例经机械取栓治疗后完全恢复前向血流（mTICI 3级）的PCS患者。其中,预后不良患者共20例（51.3%）。采用逐步Logistic回归分析显示,入院时美国国立卫生研究院卒中量表（NIHSS）评分较高（OR = 1.21,95%CI = 1.037~1.414,P = 0.016）、后交通动脉（PcomA）未开放（OR = 0.052,95%CI = 0.005~0.557,P = 0.014）为90 d不良预后的独立预测因素。基于ROC曲线分析显示,入院时NIHSS评分曲线下面积为0.762,截断值为20分,敏感度为70.0%,特异度为84.2%。 结论入院时NIHSS评分高、后交通动脉未开放,是后循环急性缺血性脑卒中患者接受机械取栓治疗并完全恢复前向血流后临床预后仍不佳的相关因素。     

Thromboembolic disease: variability of interobserver agreement in the interpretation of CT venography with CT pulmonary angiography

OBJECTIVE: The objective of this study was to determine interobserver agreement in the diagnosis of acute deep venous thrombosis on CT venography performed in addition to CT pulmonary angiography. SUBJECTS AND METHODS: One hundred forty-six CT venograms of 144 patients (mean age, 61.74 years) clinically suspected of having pulmonary embolism were analyzed prospectively and independently by two experienced thoracic and body imaging radiologists and later by consensus of the two radiologists. The CT venography protocol consisted of 5-mm-thick axial images at 20-mm intervals from the popliteal fossa to the renal veins. Images were acquired 3-4 min after the start of 100-150 mL of undiluted contrast medium administration at 4 mL/sec. Thirteen venous segments were analyzed in each patient. There were 1586 analyzable venous segments. RESULTS: Interobserver agreement, with the patient as the unit of analysis, was moderately good (kappa, 0.59; 95% confidence interval [CI], 0.39-0.78). Kappa values were similar for CT venography studies performed with 150 mL of contrast medium and 4-min delay (kappa, 0.62; 95% CI, 0.30-0.88) and with 3-min delay and 100 mL of contrast medium (kappa, 0.56; 95% CI, 0.32-0.80). Interobserver disagreement occurred in 17 (12%) of 146 CT venography studies. Findings of 11 CT venography studies were interpreted as negative, and six were interpreted as positive after consensus interpretation. CONCLUSION: Interobserver agreement for deep venous thrombosis with CT venography is moderately good.     

Quantitative methodology using CT for predicting survival in patients with metastatic colorectal carcinoma: a pilot study

ObjectiveTo develop a methodology which quantifies multiple changing lesion features resulting in an optimized computed tomography (CT) response score (CRS) for prediction of overall survival (OS) in response to treatment for metastatic colorectal carcinoma (MCRC).Subjects and MethodsThis Health Insurance Portability and Accountability Act-compliant, institutional review board-approved retrospective study evaluated multiple changing imaging findings and their correlation with OS with a new methodology comparing the baseline and first post-treatment CT scans in 38 MCRC patients on last-line chemotherapy (cetuximab and irinotecan). Tumor size/enhancement changes and interval development of new lesions were quantified with either Likert-type scales (all parameters) or Response Evaluation Criteria in Solid Tumors (RECIST) (size change only). The most predictive parameters for OS were used to generate the CRS with an overall range of ?3 (complete disappearance) to +2 (definite tumor increase). The Cox Hazard Ratio was used to assess prediction of survival. Reader agreement was evaluated by the kappa statistic.ResultsTumor size was the best predictor of OS using the Likert-type scale or RECIST. The CRS was not improved combining size change with other parameters. Use of the Likert-type scale resulted in predicting OS with a Cox hazard ratio of 1.697 (P=.0004) and good agreement (kappa=0.73, 95% CI=0.41–1.10) between observers with no significant difference using RECIST.ConclusionThe methodology produces a CRS for MCRC predicting OS resulting from therapy which expands standard RECIST guidelines to allow critical evaluation of multiple additional imaging parameters. Size change alone was found to be the best parameter of those considered in terms of maximizing agreement and prediction of OS.     

Multidetector row CT pulmonary angiography and indirect venography for the diagnosis of venous thromboembolic disease in intensive care unit patients

RATIONALE AND OBJECTIVES: To determine the diagnostic quality, performance characteristics and interreader reliability of computed tomography pulmonary angiography (CTPA) and venography (CTV) in intensive care unit (ICU) patients with suspected venous thromboembolism (VTE). MATERIALS AND METHODS: A total of 100 consecutive ICU patient CT examinations performed for clinically suspected VTE on a four-row CT scanner were reviewed. Three readers rated the diagnostic quality of each CTPA and CTV examination as excellent, acceptable, or nondiagnostic. Readers scored the overall determination for pulmonary embolism (PE) and deep venous thrombosis (DVT) using a 5-point scale, and scored the determination for PE by anatomic level. Receiver operator characteristic (ROC) analysis was performed for each reader and the original clinical report, using consensus interpretation as the reference standard. Interobserver variability for PE and DVT was determined using kappa analysis, and was stratified by examination quality. RESULTS: A total of 25% of CTPA examinations were nondiagnostic, most commonly because of motion artifact and poor contrast opacification. A total of 24% of CTV examinations were nondiagnostic, most commonly because of poor contrast opacification and metallic hardware. Using receiver operating characteristic analysis, the areas under the curve (Az) for PE diagnosis were 0.875, 0.923, 0.888, and 0.674 for the three readers and clinical reading, respectively, and for DVT diagnosis were 0.842, 0.859, 0.952 and 0.669. Interobserver agreement for detection of PE was moderate at the supralobar level (kappa = 0.55), very good at the lobar level (kappa = 0.69), and moderate for segmental (kappa = 0.54) and subsegmental arteries (kappa = 0.44). Overall reader agreement was good for excellent/good quality CTPA examinations (kappa = 0.52-0.56), and poor when examination quality was poor (kappa = 0.06). CONCLUSIONS: CTPA and CTV are sufficiently accurate and reliable techniques for evaluating VTE in ICU patients, particularly in light of patient complexity.     

CT angiography for evaluation of living renal donors: comparison of four reconstruction methods

OBJECTIVE: We sought to compare various reconstruction methods for CT angiographic images in evaluating living renal donors. MATERIALS AND METHODS: In 76 patients who underwent donor nephrectomy, vascular phase CT data were obtained using an MDCT scanner (detector array, 1.25 mm x 4; beam pitch, 1.5). Two radiologists independently reconstructed CT angiographic images using thick-slab volume rendering, thick-slab maximum intensity projection (MIP), sliding thin-slab volume rendering, and sliding thin-slab MIP. The radiologists counted the number of renal arteries, early branching arteries, and renal veins. We compared the accuracy rates for the detection of vessels achieved with the four types of reconstructed images, using the surgical findings as the gold standard. Agreement between the two observers and between the surgical and CT angiographic findings was evaluated. RESULTS: The sensitivity for detecting the supernumerary artery was significantly greater with sliding thin-slab volume rendering and sliding thin-slab MIP (97%) than with thick-slab volume rendering (59%) (p = 0.039). No significant difference between the other comparison pairs of reconstruction methods was found. The interobserver agreement for detecting supernumerary and early branching arteries with sliding thin-slab volume rendering and MIP was excellent (kappa = 0.820-0.859) and good for renal veins (kappa = 0.698-0.724), whereas the agreement of thick-slab volume rendering and MIP was good for arteries (kappa = 0.706-0.791) and moderate for veins (kappa = 0.443-0.579). The agreement between CT angiographic reconstructed images and surgical findings for detection of vessels was better with sliding thin-slab volume rendering and MIP (kappa = 0.793-1.000) than in thick-slab volume rendering and MIP (kappa = 0.306-0.613). CONCLUSION: For CT angiographic evaluation of living renal donors, sliding thin-slab reconstruction is superior to thick-slab reconstruction.     

Pulmonary emphysema: subjective visual grading versus objective quantification with macroscopic morphometry and thin-section CT densitometry.

PURPOSE: To compare subjective visual grading of pulmonary emphysema with macroscopic morphometry and computed tomographic (CT) densitometry. MATERIALS AND METHODS: In 62 consecutive patients who underwent thinsection CT before surgical lung resection, emphysema was objectively quantified with computer-assisted macroscopic morphometry and CT densitometry. The percentage of lung macroscopically occupied by emphysema was compared with the percentage occupied on CT scans by pixels with attenuation values lower than a predefined threshold (CT densitometry). Three readers with varying degrees of expertise subjectively graded emphysema with visual assessment at two reading sessions. Data from objective quantification and subjective grading were analyzed with correlation coefficients, and interobserver and intraobserver agreement were calculated. RESULTS: Subjective grading of emphysema showed less agreement with the macroscopic reference standard results (r = 0.439-0.505; P < .05) than with objective CT densitometric results (r = 0.555-0.623; P < .001). The 95% CIs for the intercepts of the linear regression lines were suggestive of systematic subjective overestimation of emphysema by all three readers. Interobserver agreement was moderate (kappa = 0.431-0.589). Intraobserver agreement was good to excellent (kappa = 0.738-0.936). The expertise of individual readers did not substantially influence results. CONCLUSION: Systematic overestimation and moderate interobserver agreement may compromise subjective visual grading of emphysema, which suggests that subjective visual grading should be supplemented with objective methods to achieve precise, reader-independent quantification of emphysema.     

Defining the priority of using 18F-FDG PET for recurrent cervical cancer.

PET with 18F-FDG has shown its potential in cervical cancer. For maximizing the benefits of this new imaging technology, we aimed to define the prognostic features of recurrent cervical cancer patients for selecting appropriate candidates using 18F-FDG PET. METHODS: Patients enrolled were from 2 independent prospective studies investigating the role of 18F-FDG PET in cervical cancer patients after definitive treatment with documented failure (CTRP-018) or unexplained elevated tumor marker serum levels (CTRP-016) and proven relapse after PET. A total of 55 eligible patients received PET and CT or MRI. Lesion status was determined from pathologic results or clinical follow-up. The benefits calculated were based on treatment that was modified because of the PET findings. The Cox proportional hazards ratio (HR) was used to select independent prognostic covariates. RESULTS: Thirty-six (65.5%) patients had treatment that was modified due to PET. Primary radiation (HR = 14.62; 95% confidence interval [CI] = 2.74-77.92), squamous cell carcinoma antigen (SCC-Ag) > or = 4 ng/mL (HR = 5.82; 95% CI = 1.53-22.04), and presence of symptoms (HR = 6.24; 95% CI = 1.99-19.61) at recurrence were significant factors associated with poor survival. A scoring system using these covariates defined 3 distinct prognostic groups: score < or = 1 (HR = 1.00); score = 2 (HR = 6.91; 95% CI = 1.49-32.14); and score = 3 (HR = 60.46; 95% CI = 9.68-378.09) (P < 0.0001). CONCLUSION: Using this risk score, 18F-FDG PET may offer maximal benefits by selecting appropriate recurrent cervical cancer patients for salvage therapy with precise restaging information.     

Mucin-producing adenocarcinoma of the lung: thin-section computed tomography findings in 48 patients and their effect on prognosis

OBJECTIVE: To determine the prognostic value of thin-section computed tomography (CT) findings in patients with mucin-producing adenocarcinoma (MPA) of the lung. METHODS: The study included 48 patients with pathologically proven MPA who had thin-section CT before treatment. The CT findings were correlated with the histopathologic findings and with disease-free survival on follow-up in all patients. RESULTS: Computed tomography findings identified in patients with MPA of the lung included an air bronchogram (n = 37, 77.1%), areas of ground-glass attenuation (n = 36, 75.0%), areas of air-space consolidation (n = 36, 75.0%), interlobular septal thickening (n = 33, 68.8%), bubble-like lucencies (n = 23, 47.9%), centrilobular nodules (n = 22, 45.8%), and mucus filling of airways (n = 19, 39.6%). Twenty-two (45.8%) of the 48 patients had intrapulmonary metastases. Centrilobular nodules (odds ratio [OR] = 6.7, 95% confidence interval: 1.1-41.4; P < 0.05) and mucus filling of airways (OR = 14.4, 95% 95% confidence interval: 2.0-102.7; P < 0.01) on thin-section CT were independently associated with an increased likelihood of intrapulmonary metastases. The 5-year disease-free survival rates were 67.9% and 38.4% for patients without and with intrapulmonary metastases, respectively (P < 0.05). The presence of centrilobular nodules (relative risk = 10.5, 95% confidence interval: 1.8-59.3; P < 0.01) on thin-section CT was an independent predictor of poor prognosis. CONCLUSION: Centrilobular nodules on CT are associated with a higher prevalence of intrapulmonary metastases and a poor prognosis in patients with MPA of the lung.     

Early signs of brain infarction at CT: observer reliability and outcome after thrombolytic treatment--systematic review

PURPOSE: To review systematically all reported early computed tomographic (CT) signs in acute ischemic stroke to determine interobserver agreement and the relationship between early CT signs and patient outcome with or without thrombolysis. MATERIALS AND METHODS: A systematic review of the literature was conducted by using Cochrane Stroke Group methodology to identify studies published between 1990 and 2003 that were performed to assess interobserver agreement about early signs of infarction on CT scans obtained within 6 hours after onset of stroke symptoms and determine the relation of early signs of infarction to clinical outcome, including any interactive effect of thrombolysis. Interobserver agreement was measured with the kappa statistic, sensitivity, and specificity. The relation of early signs to clinical outcome with or without thrombolysis was assessed with calculated odds ratios and 95% confidence intervals. RESULTS: In 15 studies of interobserver agreement (median of 30 CT scans and six raters), the prevalence of all early infarction signs was 61% +/- 21 (standard deviation). Interobserver agreement (kappa statistics) ranged from 0.14 to 0.78 for any early infarction sign. The mean sensitivity and specificity for detection of early infarction signs with CT were 66% (range, 20%-87%) and 87% (range, 56%-100%), respectively. Experience improved detection, but knowledge of symptoms did not. In 15 studies of early infarction signs and outcome (including seven thrombolysis trials) in 3468 patients, any early infarction sign increased the risk of poor outcome (odds ratio, 3.11; 95% confidence interval: 2.77, 3.49). Two studies that sought interaction between early infarction signs and thrombolysis found no evidence that thrombolysis given in the presence of early infarction signs resulted in worse outcome than that due to early signs alone. CONCLUSION: Further work is required to determine which signs are most reliably detected, whether scoring systems help to improve detection, and whether any early infarction sign should influence decisions concerning thrombolysis.