© www.appliedradiology.com March 2015 A “controversies” session at the 2012 Radiological Society of North America (RSNA) meeting in Chicago gathered some radiology leaders for a frank discussion of the current state of ultrasound (US) in the field and what the future may have in store. Relentless advances in technology have resulted in shifts in practice patterns, some leading to better patient care, some to a more timely diagnosis, and others to conflicts among service providers. Most radiologists are well aware of the proliferation of compact ultrasound systems among their clinical colleagues. In the era of fee-for-service medicine this development is driven by many factor— some noble; some less so. Consequently, some questions come to mind: What might we radiologists expect in the future? How do we react? How should we position ourselves?
The purpose of this study was to review the embryology, classification, imaging features and treatment options of Müllerian duct anomalies. The three embryological phases will be described and the appearance of the seven classes of Müllerian duct anomalies will be illustrated using hysterosalpingography, ultrasound and MRI. This exhibit will also review the treatment options, including interventional therapy. The role of imaging is to help detect, classify and guide surgical management. At this time, MRI is the modality of choice because of its high accuracy in detecting and accurately characterising Müllerian duct anomalies. In conclusion, radiologists should be familiar with the imaging features of the seven classes of Müllerian duct anomalies, as the appropriate course of treatment relies upon the correct diagnosis and categorisation of each anomaly.
We continue with an article that describes the people behind eponyms in radiology. The collection of the biographical details about these people took us on a fascinating search in immigration archives and into contact with family friends and descendants of these people. This search helped to find some previously unpublished data and photographs, which made a fascinating tour to the past exciting and fruitful. We discovered that eponyms sometimes emerged as a result of a single article, which was not necessarily a significant step in the author’s career. Only a few eponyms are used in radiologic practice, unlike in the specialties of neurology or surgery. Lewicki suggested that this fact as well as the end of the eponym era a few decades ago probably paralleled other changes in medicine, with the discipline becoming more scientific and less descriptive. However, eponyms help us to remember that, even today, when our lives are so dominated by technology, advancement of knowledge still depends on people. As mentioned in the first part, we were dedicated to the names behind the exclusive eponyms of radiologic signs.
OBJECTIVE:The purpose of this study was to describe the thoracic radiologic findings of chronic granulomatous disease in adults.MATERIALS AND METHODS:We retrospectively analyzed the chest radiographic and CT findings in four adults with chronic granulomatous disease during five episodes of lower respiratory tract infection.RESULTS:Chest radiographic findings included areas of consolidation (60%), diffuse reticulonodular opacities (40%), pleural effusion (20%), and pulmonary artery enlargement (20%). CT findings included areas of consolidation (60%), pulmonary nodules in a random distribution (60%), centrilobular nodules (60%), tree-in-bud opacities (40%), areas of scarring and traction bronchiectasis (100%), emphysematous changes (75%), areas of decreased attenuation and vascularity associated with air trapping on expiratory CT (50%), mediastinal and/or hilar lymphadenopathy (60%), pulmonary artery enlargement (50%), and pleural effusion (20%). Areas of consolidation and nodules were the most prominent findings and at histologic examination were found to be associated with infection or granulomatous inflammation.CONCLUSION:The pulmonary radiologic findings of chronic granulomatous disease include consolidation, nodules, areas of scarring, traction bronchiectasis, emphysema, air trapping, mediastinal and hilar lymphadenopathy, pulmonary artery enlargement, and pleural effusion.
OBJECTIVE:To evaluate the performance of a computer-aided detection (CAD) system for diagnosis of pulmonary embolism on computed tomography (CT) pulmonary angiography.MATERIALS AND METHODS:One hundred and four pulmonary CT angiograms for pulmonary emboli (PE) were reviewed both by radiologists and a CAD detection system (ImageChecker CT V2.0, R2 Technology Inc, Sunnyvale, CA). CT scans, read and reported by radiologists in a routine daily clinical setting, were later processed by the CAD system. The performance of the CAD system was analyzed.RESULTS:Forty-five PE were identified by the radiologists in 15 patients. The CAD system revealed 123 findings, interpreted by the system as PE. Twenty-six of them, detected in 8 patients, represented true-positive results. Ninety-seven (78.9%) CAD findings were not true PE and were defined as false-positive. Nineteen true PE in 7 patients were missed by the CAD system constituting 42% false-negative rate. Sensitivity of the CAD system was 53.3% and the specificity was 77.5%. The positive predictive value of CAD system was 28.5% and the negative predictive value was 90.7%.CONCLUSIONS:With the evaluated CAD system, it is relatively simple and fast to check all detected findings and decide if they represent true PE. However, high false-negative results demand technologic improvement, to increase the sensitivity of the system. It is anticipated to become a promising supplement to the work and eyes of the radiologist in detecting PE on pulmonary CT angiography.
Uterine fibroids are common benign lesions. Other common benign masses include renal cysts, renal angiomyolipomas, hepatic cysts, hepatic hemangiomas, thyroid cysts, adrenal incidentalomas, pulmonary granulomas and hamartomas, ovarian cysts, and dermoids. All these conditions, especially in asymptomatic patients, almost never have clinical significance. However, it is important to differentiate them from more sinister or even malignant lesions. In general, when a lesion is described as a fibroid, no further evaluation is performed. So if we say that a lesion is a fibroid, we have to be sure. Endometrial fibroids may mimic endometrial polyps or endometrial cancer. Subserous, especially pedunculated fibroids, may need further evaluation to differentiate them from ovarian pathology, colonic pathology, or even müllerian duct anomalies. Pelvic magnetic resonance imaging may be helpful in these cases.
Uterine fibroids are common benign lesions. Other common benign masses include renal cysts, renal angiomyolipomas, hepatic cysts, hepatic hemangiomas, thyroid cysts, adrenal incidentalomas, pulmonary granulomas and hamartomas, ovarian cysts, and dermoids. All these conditions, especially in asymptomatic patients, almost never have clinical significance. However, it is important to differentiate them from more sinister or even malignant lesions. In general, when a lesion is described as a fibroid, no further evaluation is performed. So if we say that a lesion is a fibroid, we have to be sure. Endometrial fibroids may mimic endometrial polyps or endometrial cancer. Subserous, especially pedunculated fibroids, may need further evaluation to differentiate them from ovarian pathology, colonic pathology, or even müllerian duct anomalies. Pelvic magnetic resonance imaging may be helpful in these cases.
Purpose To evaluate the performance of a commercially available computer-aided detection (CAD) system in a series of pathologically proven lung cancers. Materials and Methods Sixty-nine chest computed tomography (CT) scans obtained in 12 subjects (8 females, 4 males, age 51 to 75 y, mean 63 y) with 15 pathologically proven lung cancers were retrospectively selected from 2156 entry and follow-up CT scans from a lung cancer screening program. CT scans were retrospectively analyzed using a commercially available CAD system for detecting lung nodules. Results When first detectable proven lung cancer nodules ranged in maximum diameter from 3 to 38 mm (10.4±9.2 mm) with CAD detection sensitivity stratified by size: 0/2 (0%) ≤3 mm, 5/8 (62.5%) 4 to 10 mm, 2/3 (66.7%) 11 to 15 mm, 0/0 16 to 20 mm, 2/2 (100%) >20 mm, and overall sensitivity 9/15 (60%). The sensitivity for all CT scans (first detectable and follow-up), stratified by nodule size as above, was, respectively, 0/2, 18/25, 24/28, 6/9, 5/5, and overall 53/69 (76.8%). Excluding nodules <4 mm and pure ground-glass nodules, the sensitivity for all CT scans by size was 18/24 (75%) 4 to 10 mm, 21/22 (95.4%) 11 to 15 mm, 6/6 (100%) 16 to 20 mm, 5/5 (100%) >20 mm, and overall 50/57 (87.7%). At resection (13) or biopsy (2) nodules were: adenocarcinoma (10), squamous cell carcinoma (3), and small cell carcinoma (2). Conclusions The CAD system showed good sensitivity for solid and semisolid cancers ≥4 mm (sensitivity 87.7%) and excellent for those ≥11 mm (sensitivity >95.4%).
Purpose: Preoperative imaging of acute appendicitis is widely practised. The aim of this study is to determine the prevalence of preoperative imaging of acute appendicitis in our institution and its effect on the negative appendectomy rate and perforation rates.Methods: We undertook a retrospective review of all patients who underwent appendectomy from January 2000 to December 2004. All available preoperative ultrasound (US), computed tomography (CT), and pathology results were reviewed.Results: A total of 380 appendectomies were performed over this time period for the preoperative diagnosis of acute appendicitis. Fifty-nine patients had histologically normal appendices, giving an overall negative appendectomy rate of 15.5%. Overall, patients who had preoperative imaging showed a lower negative appendectomy rate (11.4%) than did those without imaging (22.2%). Without preoperative imaging, women had a higher negative appendectomy rate (34.3%) than did men (17.4%). Reduction in the negative appendectomy rate was demonstrated with preoperative imaging in both sexes (16.7% and 5.7%, respectively). Also demonstrated is a definite trend toward increased use of preoperative CT and away from US as the sole preoperative imaging modality. This is associated with a reduced negative appendectomy rate.Conclusions: The increased use of preoperative imaging, particularly CT, is associated with a decreased negative appendectomy rate and a decreased perforation rate at our institution.
Purpose: To determine whether local anesthetic injection or gel reduced pain during transrectal ultrasound-guided prostate biopsies and whether there was significant difference between quadrant and apex-only anesthesiaMethods: Between September 2001 and May 2002. 240 male patients with elevated prostate-specific antigen and (or) abnormal digital rectal examination were randomized into 1 of 4 groups 1) transrectal lidocaine gel, 2) quadrant lidocaine injections, 3) apex-only lidocaine injections, or 4) no local anesthetic. Patients scored their pain on a numerical rating scale where 0 indicated no pain and 10 indicated worst pain We analyzed mean and standard deviations of scores, using a 1-way analysis of variance (ANOVA) and post hoc multiple comparisons with Tukey's honestly significant difference (HSD) studentized range test to determine whether there were significant differences across the groupsResults: There was no significant difference between local anesthetic gel (mean 3 1, SD 1 9) and no anesthetic (mean 3 5, SD 1 9) or between quadrant (mean 1 7, SD 1 7) and apex-only (mean 2 0, SD 1 8) local anesthetic injections There was significant difference between quadrant injections (mean 1 7, SD 1 7) and no local anesthetic (mean 3 5, SD 1 9) and between apex-only injections (mean 2 0. SD 1 8) and no local anesthetic (mean 3 5, SD 1 9)Conclusion: There was significant pain reduction with local anesthetic injections but not with gel, and since there was no significant difference in efficacy between quadrant and apex-only injections, we recommend apex-only local anesthetic injections for transrectal ultrasound-guided prostate biopsies because it simplifies the injection procedure
OBJECTIVE Our objective was to evaluate the performance of a computer-aided detection (CAD) system for pulmonary nodule detection using low-dose screening CT images. MATERIALS AND METHODS One hundred fifty consecutive low-dose screening CT examinations were independently evaluated by a radiologist and a CAD pulmonary nodule detection system (R2 Technology) designed to identify nodules larger than 4 mm in maximum long-axis diameter. All discrepancies between the two techniques were reviewed by one of another two radiologists working in consensus with the initial interpreting radiologist, and a "true" nodule count was determined. Detected nodules were classified by size, density, and location. The performance of the initial radiologist and the CAD system were compared. RESULTS The radiologist detected 518 nodules and the CAD system, 934 nodules. Of the 1,106 separate nodules detected using the two techniques, 628 were classified as true nodules on consensus review. Of the true nodules present, the radiologist detected 518 (82%) of 628 nodules and the CAD, 456 (73%) of 628 nodules. All 518 radiologist-detected nodules were true nodules, and 456 (49%) of 934 of CAD-detected nodules were true nodules. The radiologist missed 110 true nodules that were only detected by CAD. In six patients, these were the only nodules detected in the examination, changing the imaging follow-up protocol. CAD identified 478 lesions that on consensus review were false-positive nodules, a rate of 3.19 (478/150) per patient. CONCLUSION CAD detected 72.6% of true nodules and detected nodules in six (4%) patients not identified by radiologists, changing the imaging follow-up protocol of these subjects. In this study, the combined review of low-dose CT scans by both the radiologist and CAD was necessary to identify all nodules.
Image segmentation algorithms derived from spectral clustering analysis rely on the eigenvectors of the Laplacian of a weighted graph obtained from the image. The NCut criterion was previously used for image segmentation in supervised manner. We derive a new strategy for unsupervised image segmentation. This article describes an initial investigation to determine the suitability of such segmentation techniques for ultrasound images. The extension of the NCut technique to the unsupervised clustering is first described. The novel segmentation algorithm is then performed on simulated ultrasound images. Tests are also performed on abdominal and fetal images with the segmentation results compared to manual segmentation. Comparisons with the classical NCut algorithm are also presented. Finally, segmentation results on other types of medical images are shown.
Segmentation of ultrasound images is necessary in a variety of clinical applications, but the development of automatic techniques is still an open problem. Spectral clustering techniques have recently become popular for data and image analysis. In particular, image segmentation has been proposed via the normalized cut (NCut) criterion. This article describes an initial investigation to determine the suitability of such segmentation techniques for ultrasound images. The adaptation of the NCut technique to ultrasound is described first. Segmentation is then performed on simulated ultrasound images. Tests are also performed on abdominal and fetal images with the segmentation results compared to manual segmentation. The success of the segmentation on these test cases warrants further research into NCut-based segmentation of ultrasound images. E-mail: (narchip@bwh.harvard.edu).