Adenoma localization for recurrent or persistent primary hyperparathyroidism using dynamic four-dimensional CT and venous sampling.

PURPOSE: To determine if parathyroid venous sampling (PVS) combined with four-dimensional (4D) computed tomography (CT) improves sensitivity and accuracy of identification of parathyroid adenoma in patients with recurrent or persistent primary hyperparathyroidism (pHPT) and negative technetium-99m methoxyisobutyl isonitrile ((99m)Tc-MIBI) and ultrasound (US) scans. MATERIALS AND METHODS: Both PVS and 4D CT were performed in 28 patients with recurrent or persistent pHPT and negative (99m)Tc-MIBI and US examinations. Localization by 4D CT alone and in combination with PVS and lateralization by PVS alone were retrospectively assessed for correlation with surgical results. Suspected adenomas on 4D CT were said to correlate with PVS if venous drainage identified on CT corresponded to sites of elevated parathyroid hormone concentration on PVS. Lesions difficult to identify on 4D CT were lesions < 1 cm in longest dimension. Results of 4D CT were classified as positive, negative, or equivocal. RESULTS: Surgery was performed in 22 of 28 patients. Surgery identified 23 parathyroid adenomas, 1 carcinoma, and 2 hyperplastic glands in 20 patients. 4D-CT alone localized 11 lesions in 10 patients. PVS helped localize 13 additional lesions in nine more patients and clarified two lesions that were equivocal on 4D CT. Comparing 4D CT alone with 4D CT plus PVS, the sensitivity increased from 50% to 95% (P = .004), and accuracy increased from 55% to 91% (P = .022). PVS lateralization had a sensitivity of 93.3%, positive predictive value of 66.7%, and accuracy of 63.6%. CONCLUSIONS: PVS significantly improves 4D CT localization of parathyroid adenomas in patients undergoing repeat surgery for pHPT with negative (99m)Tc-MIBI and US.

Evaluating the Referring Physician's Clinical History and Indication as a Means for Communicating Chronic Conditions That Are Pertinent at the Point of Radiologic Interpretation.

The clinical history and indication (CHI) provided with a radiological examination are critical components of a quality interpretation by the radiologist. A patient's chronic conditions offer the context in which acute symptoms and findings can be interpreted more accurately. Seven pertinent (potentially diagnosis altering) chronic conditions, which are fairly prevalent at our institution, were selected. We analyze if and how in 140 CHIs there was mention of a patient's previously reported chronic condition and if and how the condition was subsequently described in the radiology report using a four-item scheme (Mention/Specialization, Generalization, Common comorbidity, No mention). In 40.7% of CHIs, the condition was rated Mention/Specialization. Therefore, we reject our first hypothesis that the CHI is a reliable source for obtaining pertinent chronic conditions (≥ 90.0%). Non-oncological conditions were significantly more likely rated No mention in the CHI than oncological conditions (58.7 versus 8.3%, P < 0.0001). Stat cases were significantly more frequently No mention than non-stat cases (60.0 versus 31.3%, P = 0.0134). We accept our second hypothesis that the condition's rating in the CHI is significantly correlated with its rating of the final radiology report (χ(2) test, P < 0.00001). Our study demonstrates an alarming lack of communication of pertinent medical information to the radiologist, which may negatively impact interpretation quality. Presenting automatically aggregated patient information to the radiologist may be a potential avenue for improving interpretation and adding value of the radiology department to the care chain.

Evolving role of MRI in Crohn's disease.

MR enterography is playing an evolving role in the evaluation of small bowel Crohn's disease (CD). Standard MR enterography includes a combination of rapidly acquired T2 sequence, balanced steady-state acquisition, and contrast enhanced T1-weighted gradient echo sequence. The diagnostic performance of these sequences has been shown to be comparable, and in some respects superior, to other small bowel imaging modalities. The findings of CD on MR enterography have been well described in the literature. New and emerging techniques such as diffusion-weighted imaging (DWI), dynamic contrast enhanced MRI (DCE-MRI), cinematography, and magnetization transfer, may lead to improved accuracy in characterizing the disease. These advanced techniques can provide quantitative parameters that may prove to be useful in assessing disease activity, severity, and response to treatment. In the future, MR enterography may play an increasing role in management decisions for patients with small bowel CD; however, larger studies are needed to validate these emerging MRI parameters as imaging biomarkers.

Prognostic value of metabolic tumor burden in lung cancer.

Accurate prognosis in patients with lung cancer is important for clinical decision making and treatment selection. The TNM staging system is currently the main method for establishing prognosis. Using this system, patients are grouped into one of four stages based on primary tumor extent, nodal disease, and distant metastases. However, each stage represents a range of disease extent and may not on its own be the best reflection of individual patient prognosis. (18)F-fluorodeoxyglucose-positron emission tomography ((18)F-FDG-PET) can be used to evaluate the metabolic tumor burden affecting the whole body with measures such as metabolic tumor volume (MTV) and total lesion glycolysis (TLG). MTV and TLG have been shown to be significant prognostic factors in patients with lung cancer, independent of TNM stage. These metabolic tumor burden measures have the potential to make lung cancer staging and prognostication more accurate and quantitative, with the goal of optimizing treatment choices and outcome predictions.

ACR Appropriateness Criteria® Pulsatile Abdominal Mass, Suspected Abdominal Aortic Aneurysm: 2023 Update.

Abdominal aortic aneurysm (AAA) is defined as abnormal dilation of the infrarenal abdominal aortic diameter to 3.0 cm or greater. The natural history of AAA consists of progressive expansion and potential rupture. Although most AAAs are clinically silent, a pulsatile abdominal mass identified on physical examination may indicate the presence of an AAA. When an AAA is suspected, an imaging study is essential to confirm the diagnosis. This document reviews the relative appropriateness of various imaging procedures for the initial evaluation of suspected AAA. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

ACR Appropriateness Criteria® Nontraumatic Aortic Disease.

Nontraumatic aortic disease can be caused by a wide variety of disorders including congenital, inflammatory, infectious, metabolic, neoplastic, and degenerative processes. Imaging examinations such as radiography, ultrasound, echocardiography, catheter-based angiography, CT, MRI, and nuclear medicine examinations are essential for diagnosis, treatment planning, and assessment of therapeutic response. Depending upon the clinical scenario, each of these modalities has strengths and weaknesses. Whenever possible, the selection of a diagnostic imaging examination should be based upon the best available evidence. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment. The purpose of this document is to assist physicians select the most appropriate diagnostic imaging examination for nontraumatic aortic diseases.

ACR Appropriateness Criteria® Thoracic Outlet Syndrome.

Thoracic outlet syndrome (TOS) is the clinical entity that occurs with compression of the brachial plexus, subclavian artery, and/or subclavian vein at the superior thoracic outlet. Compression of each of these structures results in characteristic symptoms divided into three variants: neurogenic TOS, venous TOS, and arterial TOS, each arising from the specific structure that is compressed. The constellation of symptoms in each patient may vary, and patients may have more than one symptom simultaneously. Understanding the various anatomic spaces, causes of narrowing, and resulting neurovascular changes is important in choosing and interpreting radiological imaging performed to help diagnose TOS and plan for intervention. This publication has separated imaging appropriateness based on neurogenic, venous, or arterial symptoms, acknowledging that some patients may present with combined symptoms that may require more than one study to fully resolve. Additionally, in the postoperative setting, new symptoms may arise altering the need for specific imaging as compared to preoperative evaluation. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Recutting prostate needle core biopsies with high grade prostatic intraepithelial neoplasia increases detection of adenocarcinoma.

OBJECTIVES: We sought to evaluate the ability of biopsy core recutting to increase cancer detection in patients with high grade prostatic intraepithelial neoplasia (HGPIN). METHODS: This prospective study encompasses all patients undergoing 12 core TRUS guided prostate biopsy between February 2004 and January 2007. In patients with HGPIN on initial biopsy, the paraffin blocks were resampled for cancer by additional deeper levels per core. Additional analysis was performed in the patients with HGPIN in order to detect whether significant differences in prebiopsy variables were associated with patients subsequently found to have benign versus carcinoma on recutting. Last, the costs associated with this procedure were studied. RESULTS: Forty of 584 (6.8%) patients undergoing prostate biopsy were found to have HGPIN in the absence of prostatic adenocarcinoma on initial histopathology. Following recutting, 12.5% (5/40) of these patients were found to have prostatic adenocarcinoma not previously detected. Of the remaining 35 patients, 18 underwent repeat biopsy. Of these, five patients were found to have adenocarcinoma and three were found to have persistent HGPIN. The PSA, PSA density (PSAD), and PSA velocity (PSAV) prior to initial biopsy were not statistically different when comparing patients found to have benign tissue versus carcinoma on recutting. In patients with HGPIN, at our institution, recutting the biopsy would yield a cost savings of $436/patient as opposed to universal rebiopsy. CONCLUSIONS: Our data suggest that prostate biopsy recutting may increase cancer detection in patients initially found to have HGPIN. Additionally, a significant cost savings is associated with the recutting protocol.

ACR Appropriateness Criteria® Nonatherosclerotic Peripheral Arterial Disease.

A broad range of nonatherosclerotic diseases affect the peripheral arteries. The appropriate initial diagnostic imaging studies vary, depending upon the clinical presentation and suspicion of disease. Accurate vascular imaging relies upon visualization of the vessel lumen, vessel wall, and surrounding soft-tissue structures, with some modalities also offering the ability to characterize blood flow direction and velocity. Furthermore, nonvascular findings are often paramount in supporting a suspected clinical syndrome or guiding surgical management. The scenarios discussed in this document include the initial evaluation of suspected popliteal entrapment syndrome, external iliac artery endofibrosis, lower-extremity inflammatory vasculitides, dissection or connective tissue disease, noninflammatory vascular disease, and vascular trauma. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Abdominal Aortic Aneurysm Follow-up (Without Repair).

Abdominal aortic aneurysm (AAA) is defined as aneurysmal dilation of the abdominal aorta to 3 cm or greater. A high degree of morbidity and mortality is associated with AAA rupture, and imaging surveillance plays an essential role in mitigating the risk of rupture. Aneurysm size and growth rate are factors associated with the risk of rupture, thus surveillance imaging studies must be accurate and reproducible to characterize aneurysm size. Ultrasound, CT angiography, and MR angiography provide an accurate and reproducible assessment of size, while radiographs and aortography provide limited evaluation. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Clinically Suspected Vascular Malformation of the Extremities.

Vascular malformations of the extremities represent a wide spectrum of lesions, broadly divided into high-flow and low-flow categories. High-flow lesions include arteriovenous malformations and arteriovenous fistulas, while the more common low-flow lesions consist of venous and lymphatic malformations. The clinical presentation of vascular malformations is variable and can include extremity pain, discoloration, focal mass, or diffuse extremity enlargement. A vascular murmur can also be present and is more typical of high-flow lesions. While vascular malformations can often be diagnosed or strongly suspected by clinical features alone, imaging is often used to confirm the diagnosis, determine lesion characteristics and extent, and/or plan for treatment. Among the imaging options available, those usually appropriate for initial imaging of suspected vascular malformation are MR angiography without and with intravenous contrast, MRI without and with intravenous contrast, CT angiography with intravenous contrast, or US duplex Doppler. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Epidermal growth factor receptor signaling is up-regulated in human colonic aberrant crypt foci.

Aberrant crypt foci (ACF) are collections of abnormal colonic crypts with heterogeneous molecular and pathologic characteristics. Large and dysplastic ACF are putative precursors of colon cancer with neoplastic risk related to increased proliferation. In this study, we examined the role of epidermal growth factor receptor (EGFR) signaling in regulating ACF proliferation. Using magnification chromoendoscopy, we collected large ACF with endoscopic features of dysplasia and separately biopsied adjacent mucosa. Transcript levels were measured by real-time PCR, proteins were assessed by Western blotting, and levels were expressed as fold changes of adjacent mucosa. K-ras and B-Raf mutations were assessed by PCR and Ras activation by the ratio Ras-GTP / (Ras-GTP + Ras-GDP). At the RNA level, 38% of ACF were hyperproliferative, with proliferating cell nuclear antigen (PCNA) mRNA >/=2-fold of adjacent mucosa. Hyperproliferative ACF had significantly increased mRNA levels of EGFR (6.0 +/- 1.7-fold), transforming growth factor-alpha (14.4 +/- 5.0-fold), heparin-binding EGF-like growth factor (4.5 +/- 1.4-fold), cyclin D1 (4.6 +/- 0.7-fold), and cyclooxygenase-2 (COX-2; 9.3 +/- 4.2-fold; P < 0.05). At the protein level, 46% of ACF were hyperproliferative (PCNA, 3.2 +/- 1.2-fold). In hyperproliferative ACF, 44% possessed significant increases in four EGFR signaling components: EGFR (9.5 +/- 1.3-fold), phosphoactive ErbB2 (2.6 +/- 0.4-fold), phosphoactive extracellular signal-regulated kinase (3.7 +/- 1.1-fold), and cyclin D1 (3.4 +/- 0.8-fold; P < 0.05). Ras was activated in 46% of ACF (3.2 +/- 0.4-fold; P < 0.05), but K-ras mutations were present in only 7% of ACF. In contrast to COX-2 mRNA, the protein was not increased in hyperproliferative ACF. In summary, we have shown that ACF with up-regulated PCNA possess increased EGFR signaling components that likely contribute to the enhanced proliferative state of dysplastic-appearing ACF.

Relative value of three whole-body MR approaches for PET-MR, including gadofosveset-enhanced MR, in comparison to PET-CT.

PURPOSE: Evaluate MR protocol for PET-MR including coronal DWI (cDWI), fat-suppressed T2 (T2w), and gadofosveset-enhanced T1 (CE). MATERIALS AND METHODS: 18 patients underwent same-day PET-CT and PET-MR. Image quality and performance of each sequence, and combination of all three sequences, was evaluated with respect to PET-CT. RESULTS: Lesion conspicuity was best on cDWI, while delineation was best on CE. Considering all three sequences combined, both readers showed good sensitivity and specificity (>80%). Relative sensitivity was highest on CE and lowest on T2w. CONCLUSIONS: Whole-body MR performed well in detecting malignant lesions compared to PET-CT. CE showed overall highest performance.

The impact of computed high b-value images on the diagnostic accuracy of DWI for prostate cancer: A receiver operating characteristics analysis.

To evaluate the performance of computed high b value diffusion-weighted images (DWI) in prostate cancer detection. 97 consecutive patients who had undergone multiparametric MRI of the prostate followed by biopsy were reviewed. Five radiologists independently scored 138 lesions on native high b-value images (b = 1200 s/mm2), apparent diffusion coefficient (ADC) maps, and computed high b-value images (contrast equivalent to b = 2000 s/mm2) to compare their diagnostic accuracy. Receiver operating characteristic (ROC) analysis and McNemar's test were performed to assess the relative performance of computed high b value DWI, native high b-value DWI and ADC maps. No significant difference existed in the area under the curve (AUC) for ROCs comparing B1200 (b = 1200 s/mm2) to computed B2000 (c-B2000) in 5 readers. In 4 of 5 readers c-B2000 had significantly increased sensitivity and/or decreased specificity compared to B1200 (McNemar's p < 0.05), at selected thresholds of interpretation. ADC maps were less accurate than B1200 or c-B2000 for 2 of 5 readers (P < 0.05). This study detected no consistent improvement in overall diagnostic accuracy using c-B2000, compared with B1200 images. Readers detected more cancer with c-B2000 images (increased sensitivity) but also more false positive findings (decreased specificity).

ACR Appropriateness Criteria® Imaging of Mesenteric Ischemia.

Mesenteric ischemia is an uncommon condition resulting from decreased blood flow to the small or large bowel in an acute or chronic setting. Acute ischemia is associated with high rates of morbidity and mortality; however, it is difficult to diagnose clinically. Therefore, a high degree of suspicion and prompt imaging evaluation are necessary. Chronic mesenteric ischemia is less common and typically caused by atherosclerotic occlusion or severe stenosis of at least two of the main mesenteric vessels. While several imaging examination options are available for the initial evaluation of both acute and chronic mesenteric ischemia, CTA of the abdomen and pelvis is overall the most appropriate choice for both conditions. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Lower Extremity Arterial Revascularization-Post-Therapy Imaging.

Peripheral arterial disease (PAD) affects millions across the world and in the United States between 9% to 23% of all patients older than 55 years. The refinement of surgical techniques and evolution of endovascular approaches have improved the success rates of revascularization in patients afflicted by lower extremity PAD. However, restenosis or occlusion of previously treated vessels remains a pervasive issue in the postoperative setting. A variety of different imaging options are available to evaluate patients and are reviewed within the context of asymptomatic and symptomatic patients with PAD who have previously undergone endovascular or surgical revascularization. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Quantitative radiology: automated measurement of polyp volume in computed tomography colonography using Hessian matrix-based shape extraction and volume growing.

BACKGROUND: Current measurement of the single longest dimension of a polyp is subjective and has variations among radiologists. Our purpose was to develop a computerized measurement of polyp volume in computed tomography colonography (CTC). METHODS: We developed a 3D automated scheme for measuring polyp volume at CTC. Our scheme consisted of segmentation of colon wall to confine polyp segmentation to the colon wall, extraction of a highly polyp-like seed region based on the Hessian matrix, a 3D volume growing technique under the minimum surface expansion criterion for segmentation of polyps, and sub-voxel refinement and surface smoothing for obtaining a smooth polyp surface. Our database consisted of 30 polyp views (15 polyps) in CTC scans from 13 patients. Each patient was scanned in the supine and prone positions. Polyp sizes measured in optical colonoscopy (OC) ranged from 6-18 mm with a mean of 10 mm. A radiologist outlined polyps in each slice and calculated volumes by summation of volumes in each slice. The measurement study was repeated 3 times at least 1 week apart for minimizing a memory effect bias. We used the mean volume of the three studies as "gold standard". RESULTS: Our measurement scheme yielded a mean polyp volume of 0.38 cc (range, 0.15-1.24 cc), whereas a mean "gold standard" manual volume was 0.40 cc (range, 0.15-1.08 cc). The "gold-standard" manual and computer volumetric reached excellent agreement (intra-class correlation coefficient =0.80), with no statistically significant difference [P (F≤f) =0.42]. CONCLUSIONS: We developed an automated scheme for measuring polyp volume at CTC based on Hessian matrix-based shape extraction and volume growing. Polyp volumes obtained by our automated scheme agreed excellently with "gold standard" manual volumes. Our fully automated scheme can efficiently provide accurate polyp volumes for radiologists; thus, it would help radiologists improve the accuracy and efficiency of polyp volume measurements in CTC.

Prospective Comparison of 99mTc-MDP Scintigraphy, Combined 18F-NaF and 18F-FDG PET/CT, and Whole-Body MRI in Patients with Breast and Prostate Cancer.

UNLABELLED: We prospectively evaluated the use of combined (18)F-NaF/(18)F-FDG PET/CT in patients with breast and prostate cancer and compared the results with those for (99m)Tc-MDP bone scintigraphy and whole-body MRI. METHODS: Thirty patients (15 women with breast cancer and 15 men with prostate cancer) referred for standard-of-care bone scintigraphy were prospectively enrolled in this study. (18)F-NaF/(18)F-FDG PET/CT and whole-body MRI were performed after bone scintigraphy. The whole-body MRI protocol consisted of both unenhanced and contrast-enhanced sequences. Lesions detected with each test were tabulated, and the results were compared. RESULTS: For extraskeletal lesions, (18)F-NaF/(18)F-FDG PET/CT and whole-body MRI had no statistically significant differences in sensitivity (92.9% vs. 92.9%, P = 1.00), positive predictive value (81.3% vs. 86.7%, P = 0.68), or accuracy (76.5% vs. 82.4%, P = 0.56). However, (18)F-NaF/(18)F-FDG PET/CT showed significantly higher sensitivity and accuracy than whole-body MRI (96.2% vs. 81.4%, P < 0.001, 89.8% vs. 74.7%, P = 0.01) and bone scintigraphy (96.2% vs. 64.6%, P < 0.001, 89.8% vs. 65.9%, P < 0.001) for the detection of skeletal lesions. Overall, (18)F-NaF/(18)F-FDG PET/CT showed higher sensitivity and accuracy than whole-body MRI (95.7% vs. 83.3%, P < 0.002, 87.6% vs. 76.0%, P < 0.02) but not statistically significantly so when compared with a combination of whole-body MRI and bone scintigraphy (95.7% vs. 91.6%, P = 0.17, 87.6% vs. 83.0%, P = 0.53). (18)F-NaF/(18)F-FDG PET/CT showed no significant difference from a combination of (18)F-NaF/(18)F-FDG PET/CT and whole-body MRI. No statistically significant differences in positive predictive value were noted among the 3 examinations. CONCLUSION: (18)F-NaF/(18)F-FDG PET/CT is superior to whole-body MRI and (99m)Tc-MDP scintigraphy for evaluation of skeletal disease extent. Further, (18)F-NaF/(18)F-FDG PET/CT and whole-body MRI detected extraskeletal disease that may change the management of these patients. (18)F-NaF/(18)F-FDG PET/CT provides diagnostic ability similar to that of a combination of whole-body MRI and bone scintigraphy in patients with breast and prostate cancer. Larger cohorts are needed to confirm these preliminary findings, ideally using the newly introduced simultaneous PET/MRI scanners.

Quantification of metabolic tumor activity and burden in patients with non-small-cell lung cancer: Is manual adjustment of semiautomatic gradient-based measurements necessary?

PURPOSE: Metabolic tumor burden (MTB) measurements including metabolic tumor volume and total lesion glycolysis have been shown to have prognostic value in non-small-cell lung cancer (NSCLC). The calculation of MTB typically utilizes software to semiautomatically draw volumes of interest around the tumor, which are subsequently manually adjusted by the radiologist to include the entire tumor. The manual adjustment step can be time-consuming and observer-dependent. We compared the agreement of MTB values obtained using the semiautomatic method with and without manual adjustment in NSCLC patients. METHODS: This IRB-approved prospective study included 134 patients with histologically proven NSCLC who underwent fluorine-18 fluorodeoxyglucose PET/computed tomography. The MTB of the primary tumor was measured with a semiautomatic gradient-based method without manual adjustment (the semiautomatic gradient method) and with manual adjustment (the manually adjusted semiautomatic gradient method) by two radiologists using the MIM PETedge tool. The paired t-test, Wilcoxon signed-rank test, and concordance correlation coefficient (CCC) were calculated to evaluate the agreement between MTB measures obtained with these two methods, as well as agreement between the two radiologists for each method. RESULTS: Maximum standardized uptake value was identical between the two methods. No statistically significant difference was present for peak standardized uptake value, metabolic tumor volume, and total lesion glycolysis values between the two methods (P=0.23, 0.45, and 0.37, respectively). Excellent agreement between the two methods was found in terms of CCC (CCC>0.98 for all measures). Interobserver reliability was excellent for all measures (CCC>0.90). CONCLUSION: The semiautomatic gradient-based tumor-segmentation method can be used without the additional manual adjustment step for MTB quantification of primary NSCLC tumors.

BMI-based radiation dose reduction in CT colonography.

RATIONALE AND OBJECTIVES: There is potential for x-ray dose reduction in computed tomography colonography (CTC) relative to body mass index (BMI). We evaluated the association between BMI and three-dimensional (3D) CTC image quality to assess the potential utility of BMI as the basis for radiation dose reduction in CTC. MATERIALS AND METHODS: Ninety-six consecutive patients underwent CTC and were randomized for scanning at 15 or 30 mAs. Extremely obese patients (BMI > 50) were excluded. Each patient was scanned supine and prone on a multidetector CT scanner. Postprocessing CTC visualization was performed on a dedicated workstation. Three independent observers assessed 3D image quality using a four-point scale. Image noise was measured in both the abdomen and pelvis. The association between BMI and image noise was examined using random-effects linear regression models. Logistic regression was used to examine the relationship between BMI, mAs, and conspicuity scores. RESULTS: Statistically significant differences in image noise were observed between 15 and 30 mAs in both the abdomen and pelvis, and the difference was greater with increasing BMI. A positive relationship was detected between BMI and noise in the abdomen (P < .001) and pelvis (P < .001). Inverse correlation was identified between BMI and conspicuity scores in the abdomen (P = .01) and pelvis (P < .001). Overall conspicuity scores were reduced for both 15 and 30 mAs groups as BMI increased. CONCLUSION: The radiation dose for CTC can be reduced by 40% and 70% below commonly employed doses for overweight and normal BMI patients, respectively, by using a BMI-adjusted dose reduction approach. Conspicuity scores dropped in obese patients with reduced dose suggesting that standard accepted doses should be utilized in that group.