Evan S. Siegelman

University of Pennsylvania, Filadelfia, Pennsylvania, United States

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Publications (187)656.04 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: To determine the diagnostic performance of magnetic resonance imaging (MRI) in the diagnosis of acute appendicitis during pregnancy in a multi-institutional study. In this multicenter retrospective study, pregnant females who underwent MRI evaluation of abdominal or pelvic pain and had clinical suspicion of acute appendicitis between June 1, 2009 and July 31, 2014 were reviewed. All MRI examinations with positive findings for acute appendicitis were confirmed with surgical pathology. Sensitivity, specificity, negative predictive values and positive predictive values were calculated. Receiver operating characteristic curves were generated and area under the curve analysis was performed for each participating institution. 9.3% (66/709) had MRI findings of acute appendicitis. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive values were 96.8%, 99.2%, 99.0%, 92.4%, and 99.7%, respectively. There was no statistically significant difference between centers included in the study (pair-wise p values ranged between 0.12-0.99). MRI imaging is useful and reproducible in the diagnosis of suspected acute appendicitis during pregnancy. Copyright © 2015 Elsevier Inc. All rights reserved.
    American journal of obstetrics and gynecology 07/2015; DOI:10.1016/j.ajog.2015.07.026 · 4.70 Impact Factor
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    ABSTRACT: The purpose of this article is to present a contemporary review of the imaging appearance of diseases which affect the deeper layers of the urinary bladder, including both suburothelial and extrinsic pathologies, using radiologic-pathologic correlation. Compared to the more common urothelial lesions, at cystoscopy, suburothelial and extrinsic diseases of the urinary bladder wall often have a non-specific appearance or may be occult. Cross-sectional imaging, in particular MRI, plays an integral role in diagnosis. Mesenchymal tumors have distinct imaging features on MRI. Leiomyomas are characteristically low signal intensity on T2-weighted (T2W) imaging and progressively enhance. Lipomas and lipomatous hypertrophy are diagnosed by the presence of macroscopic fat. Neurofibromas, hemangiomas, and paragangliomas are hyperintense on T2W sequences and hypervascular. Reactive lesions occur in the setting of chronic inflammation and include: nephrogenic adenoma, cystitis cystica, and cystitis glandularis. Imaging findings are commonly non-specific; however, a mass with internal cystic spaces in association with pelvic lipomatosis is suggestive of cystitis glandularis. Urachal anomalies may be complicated by infection or malignancy. Urachal mucinous adenocarcinoma has a poor prognosis and may present as a T2-hyperintense suburothelial/extrinsic mass centered in the bladder dome. Other diseases may extrinsically involve the urinary bladder by hematogenous and peritoneal spread, including infection, endometriosis, and malignancy. A familiarity with suburothelial and extrinsic pathologies of the urinary bladder is critical for the radiologist, who may be the first to suggest these diagnoses.
    Abdominal Imaging 06/2015; 40(7). DOI:10.1007/s00261-015-0467-z · 1.63 Impact Factor
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    ABSTRACT: Little is known about whether the 2006 Sendai guidelines or 2012 Fukuoka guidelines are being used to determine the level of risk posed by suspected pancreatic mucinous cystic neoplasms (PCN). We evaluated whether the guidelines accurately predicted which patients with suspected PCN, based on cross-sectional imaging findings, would be found to have advanced neoplasia in surgery. We performed a retrospective study of data collected from 194 patients with cystic lesions of the pancreas, assessed by cross-sectional imaging analyses, who underwent surgery for suspected PCN at the Hospital at the University of Pennsylvania from 2000 through 2008. Imaging data were used to classify patients, according to the Sendai guidelines, as high risk (SGHR) or low risk (SGLR), and according to the Fukuoka guidelines as high risk (FGHR), worrisome (FGW), or low risk (FGLR). Pathology analyses of samples collected during surgery were used as the reference. A logistic regression model was created to identify factors associated with advanced neoplasia. The Sendai and Fukuoka guideline criteria were analyzed by univariate and multivariable logistic regression analyses. Advanced neoplasias were found in 36 patients (18.5%; 22 invasive cancers and 14 high-grade dysplasias). The median size of cysts was 33 mm. All patients found to have invasive cancers were accurately assigned to the SGHR or FGHR groups. However, 3 patients in the SGLR and 2 patients in the FGLR groups were found to have high-grade dysplasia. The Sendai guidelines identified patients with advanced neoplasia with 91.7% sensitivity, 21.5% specificity, a 21% positive predictive value, and a 91.9% negative predictive value. A designation of FGHR identified patients with advanced neoplasia with 55.6% sensitivity, 73% specificity, a 32% positive predictive value, and an 87.9% negative predictive value. Overall, there was no statistically significant difference between the guidelines in predicting which patients had advanced neoplasia. On multivariate analysis, the presence of a mural nodule (odds ratio [OR], 2.88; 95% confidence interval [CI], 1.33-6.27; P=.008), dilated MPD > 10 mm (OR, 7.44; 95% CI, 2.36-23.52; P=.001), or enhancing solid component (OR, 2.92; 95% CI, 1.16-7.64; P=.02) were associated with detection of advanced neoplasia in pancreatic cysts. Based on a retrospective analysis, the Sendai and Fukuoka guidelines accurately determine which patients with pancreatic cysts have advanced neoplasia. The guidelines accurately recommended surgical resection for all patients found to have invasive cancer, though some patients with high-grade dysplasia were missed. The updated Fukuoka guidelines are not superior to the Sendai guidelines in identifying neoplasias. Cyst size was not associated with advanced neoplasia. Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights reserved.
    Clinical gastroenterology and hepatology: the official clinical practice journal of the American Gastroenterological Association 03/2015; DOI:10.1016/j.cgh.2015.03.017 · 7.90 Impact Factor
  • Avita K. Pahwa · Evan S. Siegelman · Lily A. Arya
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    ABSTRACT: Pelvic organ prolapse, a herniation of pelvic organs through the vagina, is a common condition in older women. Pelvic organ prolapse distorts vaginal anatomy making pelvic examination difficult. A clinician must accurately identify anatomic landmarks both in women presenting with symptoms of prolapse and in women noted to have coincidental prolapse during routine gynecologic examination. We present a systematic approach to the female pelvic examination including anatomic landmarks of the external genitalia, vagina, and uterus in women with normal support as well as changes that occur with pelvic organ prolapse. Knowledge and awareness of normal anatomic landmarks will improve a clinician's ability to identify defects in pelvic support and allow for better diagnosis and treatment of pelvic organ prolapse. Clin. Anat., 2014. © 2014 Wiley Periodicals, Inc.
    Clinical Anatomy 09/2014; 28(3). DOI:10.1002/ca.22472 · 1.33 Impact Factor
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    ABSTRACT: Objectives: The aim of this study was to determine the accuracy of pelvic magnetic resonance imaging (MRI) diagnoses compared with the final pathology diagnoses for a series of women with indeterminate adnexal masses. Materials and methods: We performed a retrospective cohort study of women who underwent pelvic MRI with a diagnosis of an adnexal mass between June 2009 and 2010 after indeterminate ultrasound at our tertiary care institution. Chart abstraction was performed for demographic information and radiologic interpretations (benign or malignant) and favored a specific histologic subtype on MRI reports. The radiologic diagnoses were compared with the diagnoses by surgical pathology. Results: Data from 237 female patients who underwent pelvic MRI were included, and 41.35% underwent surgical intervention for the adnexal mass. Pelvic MRI (n = 88) was determined to have a sensitivity of 95.0% and specificity of 94.1%. The predicted specific histologic subtype by MRI (n = 84) was accurate in 56 (98.25%) of 57 women with an anticipated benign diagnosis and in 23 (85.19%) of 27 women with an anticipated malignancy. The agreement between a benign diagnosis from MRI and benign final surgical pathology was 0.85 (95% confidence interval, 0.716-0.976). Conclusions: In our tertiary care center, MRI is used to further characterize indeterminate adnexal masses and can accurately differentiate benign versus malignant adnexal masses. The diagnosis on MRI was highly correlative with the final histopathology. The majority of the cohort (59%) were able to be managed expectantly based on reassuring results of the MRI. Magnetic resonance imaging offered diagnostic value, more detailed patient counseling, appropriate subspecialty referral, and surgical planning, as well as reassurance to pursue conservative management of benign masses by MRI.
    International Journal of Gynecological Cancer 09/2014; 24(7):1215-1221. DOI:10.1097/IGC.0000000000000203 · 1.96 Impact Factor
  • Evan S. Siegelman · Anil Chauhan
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    ABSTRACT: Magnetic resonance (MR) can characterize specific tissue subtypes, thus facilitating focal liver lesion diagnosis. Focal liver lesions that are isointense to hyperintense to liver on T1-weighted images are usually hepatocellular in origin. Chemical shift imaging can narrow the differential diagnosis by detecting the presence of lipid or iron. T2 and heavily T2-weigthed fast spin echo imaging can differentiate solid from nonsolid focal liver lesions. The authors illustrate these MR imaging pearls and the uncommon exceptions (pitfalls). The authors hope that you will find this less traditional contribution to the Magnetic Resonance Clinics of North America helpful in clinical practice.
    Magnetic Resonance Imaging Clinics of North America 08/2014; 22(3):295–313. DOI:10.1016/j.mric.2014.04.005 · 0.99 Impact Factor
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    ABSTRACT: Chemical shift (CS) MRI of the adrenal glands exploits the different precessional frequencies of fat and water protons to differentiate the intracytoplasmic lipid-containing adrenal adenoma from other adrenal lesions. The purpose of this review is to illustrate both technical and interpretive pitfalls of adrenal imaging with CS MRI and emphasize the importance of adherence to strict technical specifications and errors that may occur when other imaging features and clinical factors are not incorporated into the diagnosis. When performed properly, the specificity of CS MRI for the diagnosis of adrenal adenoma is over 90%. Sampling the in-phase and opposed-phase echoes in the correct order and during the same breath-hold are essential requirements, and using the first echo pair is preferred, if possible. CS MRI characterizes more adrenal adenomas then unenhanced CT but may be non-diagnostic in a proportion of lipid-poor adenomas; CT washout studies may be able to diagnose these lipid-poor adenomas. Other primary and secondary adrenal tumours and supra-renal disease entities may contain lipid or gross fat and mimic adenoma or myelolipoma. Heterogeneity within an adrenal lesion that contains intracytoplasmic lipid could be due to myelolipoma, lipomatous metaplasia of adenoma, or collision tumour. Correlation with previous imaging, other imaging features, clinical history, and laboratory investigations can minimize interpretive errors.
    Clinical Radiology 07/2014; 69(11). DOI:10.1016/j.crad.2014.06.020 · 1.76 Impact Factor
  • Benjamin L Yam · Evan S Siegelman
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    ABSTRACT: Although ultrasound, computed tomography, and cholescintigraphy play essential roles in the evaluation of suspected biliary abnormalities, magnetic resonance (MR) imaging and MR cholangiopancreatography can be used to evaluate inconclusive findings and provide a comprehensive noninvasive assessment of the biliary tract and gallbladder. This article reviews standard MR and MR cholangiopancreatography techniques, clinical applications, and pitfalls. Normal biliary anatomy and variants are discussed, particularly as they pertain to preoperative planning. A spectrum of benign and malignant biliary processes is reviewed, emphasizing MR findings that aid in characterization.
    Radiologic Clinics of North America 07/2014; 52(4):725-755. DOI:10.1016/j.rcl.2014.02.011 · 1.98 Impact Factor
  • Journal of Obstetrics and Gynaecology 06/2014; 35(1):1-2. DOI:10.3109/01443615.2014.930095 · 0.55 Impact Factor
  • A.F. Haggerty · A.R. Hagemann · C. Chu · E. Siegelman · S.C. Rubin
    Gynecologic Oncology 06/2014; 133:90-91. DOI:10.1016/j.ygyno.2014.03.242 · 3.77 Impact Factor
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    ABSTRACT: Living donor liver transplantation (LDLT) demands a careful assessment of abnormal findings discovered during the evaluation process to determine if there will be any potential risks to the donor or recipient. Varying degrees of elevated hepatic iron levels are not uncommonly seen in otherwise healthy individuals. We questioned whether mild expression of hemosiderin deposition presents a safety concern when considering outcomes of living donation for both the donor and the recipient. We report on three LDLT patients who were found to have low- to moderate-grade hemosiderin deposition on liver biopsy. All other aspects of their evaluation proved satisfactory, and the decision was made to proceed with donation. There were no significant complications in the donors, and all demonstrated complete normalization of liver function postoperatively, with appropriate parenchymal regeneration. The recipients also had unremarkable postoperative recovery. We conclude that these individuals can be considered as potential donors after careful evaluation.
    American Journal of Transplantation 01/2014; 14(1):216-20. DOI:10.1111/ajt.12504 · 5.68 Impact Factor
  • Benjamin L. Yam · Evan S. Siegelman
    Radiologic Clinics of North America 01/2014; · 1.98 Impact Factor
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    ABSTRACT: Radiotherapy (RT) is an integral component in the management of many abdominal and pelvic malignancies. Imaging follow-up in patients who have received RT is performed to assess for treatment response, evaluate for tumour recurrence and to diagnose complications related to treatment. The purpose of this pictorial review is to depict the expected imaging findings and potential complications following RT in the genitourinary (GU) tract using an organ-based approach and to review the diagnosis of locally recurrent tumour in the GU tract following RT. Some GU malignancies, namely cervical and prostatic carcinoma, can be treated with radical RT with intent to cure. More frequently, the GU tract is indirectly treated as a result of RT to adjacent cancers. Expected imaging findings, RT-related complications and the diagnosis of recurrent tumour following RT in the GU tract often necessitate a multi-modality imaging approach, the incorporation of functional imaging techniques and an organ-based approach for diagnosis.
    Insights into Imaging 11/2013; 5(1). DOI:10.1007/s13244-013-0295-z
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    Nicola Schieda · Parvati Ramchandani · Evan S Siegelman
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    ABSTRACT: Radiation nephropathy was first recognized in 1906. The kidney is a radiosensitive organ with a tolerance dose (5% complications in 5 years) of 20 Gray. The imaging findings of acute and chronic radiation induced renal injury are previously described. Radiation-induced adrenal injury, to our knowledge, has not been described in the literature. Unlike the kidneys and other upper abdominal organs, the adrenal glands are traditionally thought to be radio-resistant, protected from radiation-induced injury by proximity to adjacent organs and by the adrenal medulla which reportedly has increased radio-resistance. We present the computed tomographic imaging findings of a patient with acute radiation induced adrenal injury which resulted in adrenal insufficiency following radiotherapy of an adjacent thecal metastasis.
    11/2013; 2(7):2047981613501305. DOI:10.1177/2047981613501305
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    ABSTRACT: This white paper describes adnexal (ovarian and paraovarian) incidental findings found on CT and MRI in nonpregnant postmenarchal patients in whom no adnexal disorder is clinically known or suspected. This represents the first of 4 such papers from the ACR Incidental Findings Committee II, which used a consensus method based on repeated reviews and revisions and a collective review and interpretation of relevant literature. Recommendations for the management of incidental adnexal findings are organized into 4 main categories: benign-appearing cysts, probably benign cysts, adnexal masses with characteristic features, and all other adnexal masses, with pathways on the basis of patient menstrual status or age (when last menstrual period is unknown). A table and flowchart are provided for reference.
    Journal of the American College of Radiology: JACR 09/2013; 10(9):675-81. DOI:10.1016/j.jacr.2013.05.023 · 2.84 Impact Factor
  • Evan S Siegelman
    Academic radiology 04/2013; 20(4):391-2. DOI:10.1016/j.acra.2013.01.001 · 1.75 Impact Factor
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    ABSTRACT: The purpose of this study was to examine early MRI changes in renal cell carcinoma (RCC) treated with the antiangiogenic agent sorafenib and to identify MRI biomarkers of RCC response to sorafenib. Sixteen patients with RCC were evaluated by MRI before and 3-12 weeks after commencing treatment with sorafenib. Two experienced MR radiologists, blinded to treatment status, independently graded tumor appearance on T1-weighted, T2-weighted, and gadolinium-enhanced images. The proportional odds mixed model was used to compare qualitative appearance of tumors before and after therapy. Time-to-progression was correlated with Response Evaluation Criteria in Solid Tumors (RECIST) 1.0 and MR-modified Choi criteria, incorporating changes in both tumor enhancement and size. After sorafenib therapy, there was a significant increase in T1 signal intensity of tumors (p < 0.0001) and a significant decrease in degree of tumor enhancement (p < 0.0001). The sum of unidimensional tumor diameters decreased significantly after therapy (p = 0.005). However, the average decrease in size at early follow-up was 13%, and all patients except one had stable disease by RECIST 1.0. Early responders defined by MR-modified Choi criteria had increased time-to-progression compared with nonresponders, whereas early RECIST evaluation did not predict clinical outcome. Decreased enhancement and T1 shortening of tumors on MRI may be useful biomarkers of RCC response to angiogenesis inhibitors. Response criteria combining early changes in size and enhancement lead to better correlation with clinical outcome compared with size decrease alone.
    American Journal of Roentgenology 01/2013; 200(1):120-6. DOI:10.2214/AJR.12.8536 · 2.73 Impact Factor
  • Evan Spencer Siegelman
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    ABSTRACT: LEARNING OBJECTIVES 1) Understand how MR can characterize tissue and facilitate the detection and staging of neoplasms in the abdomen and pelvis. 2) Appreciate how the audience response system provides immediate feeback, and enhances the learning process.
    Radiological Society of North America 2012 Scientific Assembly and Annual Meeting; 11/2012
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    ABSTRACT: PURPOSE Quantitative assessment of cancer response is a time-consuming activity. We recently developed the open-source electronic Physician Annotation Device (ePAD) to streamline this process by facilitating reader annotations on images, tracking target lesions, and automatically generating RECIST tables. Our objective is to determine the impact of ePAD on reader efficiency in performing RECIST analyses. METHOD AND MATERIALS We chose CT exams of the chest, abdomen, and pelvis from an archive of imaging studies of subjects with metastatic carcinoid tumor from a Phase III therapeutic trial. Exams were selected from 20 subjects who had one baseline and three consecutive follow-up imaging exams. Five body radiologists with between 3 and 21 years of experience were recruited to perform replicate quantitative assessments of these exams using RECIST 1.1 criteria. Exams were read initially with the aid of the ePAD tool (“assisted read”) running on the Osirix imaging viewing workstation. After a thirty-day washout period, the exams were re-read using Osirix but without ePAD (“unassisted read”); in this session, RECIST tables were created by hand (per routine practice) during and after the reader review. The total time for image review and generation of the RECIST summary of measurements was tracked and analyzed with linear mixed model to compare the review time of the two methods, where the reader is treated as the random effect. RESULTS For unassisted reads, the mean review time per patient for each of the five readers was 10.7, 16.2, 8.3, 13.9 and 14.3 minutes (average 12.7 minutes), while for the assisted reads, the mean time required for each of the same five readers was 9.3, 12.0, 4.9, 10.2 and 12.6 minutes (average 9.8 minutes), respectively. On average across the five readers, the use of ePAD produced a savings of 2.9 minutes (95% CI: 1.8 to 4.0 minutes, p=0.007) per patient, representing a net increase in reader efficiency of 23%. CONCLUSION The use of the ePAD software improved reader efficiency for quantitative assessment of CT examinations using RECIST. Further evaluation of this and similar software to assist support of image interpretation and improve radiologist productivity is warranted. CLINICAL RELEVANCE/APPLICATION Tool support for quantitative imaging evaluation of quantitative imaging studies can improve radiologist efficiency, potentially making this suitable for incorporation into routine clinical practice..
    Radiological Society of North America 2012 Scientific Assembly and Annual Meeting; 11/2012
  • Evan S Siegelman · Edward R Oliver
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    ABSTRACT: Endometriosis, which is defined as the presence of ectopic endometrial glands and stroma outside the uterus, is a common cause of pelvic pain and infertility, affecting as many as 10% of premenopausal women. Because its effects may be devastating, radiologists should be familiar with the various imaging manifestations of the disease, especially those that allow its differentiation from other pelvic lesions. The "pearls" offered here are observations culled from the authors' experience with the use of magnetic resonance (MR) imaging for the detection and characterization of pelvic endometriosis. First, the inclusion of T1-weighted fat-suppressed sequences is recommended for all MR examinations of the female pelvis because such sequences facilitate the detection of small endometriomas and aid in their differentiation from mature cystic teratomas. Second, it must be remembered that benign endometriomas, like many pelvic malignancies, may exhibit restricted diffusion. Although women with endometriosis are at risk for developing clear cell and endometrioid epithelial ovarian cancers (ie, endometriosis-associated ovarian cancers), imaging findings such as enhancing mural nodules should be confirmed before a diagnosis of ovarian malignancy is offered. The presence of a dilated fallopian tube, especially one containing hemorrhagic content, is often associated with pelvic endometriosis. Deep (solid infiltrating) endometriosis can involve the pelvic ligaments, anterior rectosigmoid colon, bladder, uterus, and cul-de-sac, as well as surgical scars; the lesions often have poorly defined margins and T2 signal hypointensity as a result of fibrosis. The presence of subcentimeter foci with T2 hyperintensity representing ectopic endometrial glands within these infiltrating fibrotic masses may help establish the diagnosis. © RSNA, 2012.
    Radiographics 10/2012; 32(6):1675-91. DOI:10.1148/rg.326125518 · 2.60 Impact Factor

Publication Stats

4k Citations
656.04 Total Impact Points


  • 1997–2015
    • University of Pennsylvania
      • • Department of Radiology
      • • Department of Medicine
      Filadelfia, Pennsylvania, United States
  • 2008–2014
    • William Penn University
      Filadelfia, Pennsylvania, United States
  • 1996–2014
    • Hospital of the University of Pennsylvania
      • • Department of Radiology
      • • Division of Transplantation
      Philadelphia, Pennsylvania, United States
    • University of North Carolina at Chapel Hill
      • Department of Radiology
      North Carolina, United States
  • 2006
    • The Ohio State University
      Columbus, Ohio, United States
  • 1998
    • Rutgers New Jersey Medical School
      Newark, New Jersey, United States
  • 1991–1997
    • Thomas Jefferson University Hospitals
      • Department of Radiology
      Philadelphia, Pennsylvania, United States