ComBat Harmonization of Myocardial Radiomic Features Sensitive to Cardiac MRI Acquisition Parameters.

Purpose: To investigate the effect of ComBat harmonization methods on the robustness of cardiac MRI-derived radiomic features to variations in imaging parameters. Materials and Methods: This Health Insurance Portability and Accountability Act-compliant retrospective study used a publicly available data set of 11 healthy controls (mean age, 33 years ± 16 [SD]; six men) and five patients (mean age, 52 years ± 16; four men). A single midventricular short-axis section was acquired with 3-T MRI using cine balanced steady-state free precision, T1-weighted, T2-weighted, T1 mapping, and T2 mapping imaging sequences. Each sequence was acquired using baseline parameters and after variations in flip angle, spatial resolution, section thickness, and parallel imaging. Image registration was performed for all sequences at a per-individual level. Manual myocardial contouring was performed, and 1652 radiomic features per sequence were extracted using baseline and variations in imaging parameters. Radiomic feature stability to change in imaging parameters was assessed using Cohen d sensitivity. The stability of radiomic features was assessed both without and after ComBat harmonization of radiomic features. Three ComBat methods were studied: parametric, nonparametric, and Gaussian mixture model (GMM). Results: For all sequences combined, 51.4% of features were robust to changes in imaging parameters when no ComBat method was applied. ComBat harmonization substantially increased the number of stable features to 95.1% (95% CI: 94.9, 95.3) when parametric ComBat was used and 90.9% (95% CI: 90.6, 91.2) when nonparametric ComBat was used. GMM combat resulted in only 52.6% stable features. Conclusion: ComBat harmonization improved the stability of radiomic features to changes in imaging parameters across all cardiac MRI sequences.Keywords: Cardiac MRI, Radiomics, ComBat, Harmonization Supplemental material is available for this article. © RSNA, 2023.

Subclinical cardiac involvement in student athletes after COVID-19 infection - Evaluation using feature tracking cardiac MRI strain analysis.

OBJECTIVES: To evaluate subclinical cardiac dysfunction in student athletes after COVID-19 infection using feature tracking cardiac MRI strain analysis. METHODS: Student athletes with history of COVID-19 infection underwent cardiac MRI as part of screening before return to competitive play. Subjects were enrolled if they had no or mild symptoms, normal cardiac MRI findings with no imaging evidence of myocarditis. Feature tracking strain analysis was performed using short and long axis cine MRI images of athletes and a separate cohort of healthy controls. Differences between the cardiac strain parameters were statistically analyzed by Mann-Whitney U test. RESULTS: The study cohort included 122 athletes (49 females, mean age 20 years ± 1.5 standard deviations) who had a history of COVID-19, and 35 healthy controls (24 females, mean age 34 years ± 18 standard deviations). COVID-19 positive athletes had normal physiologic cardiac adaptations, including significantly higher left and right ventricle end-diastolic volumes (p = 0.00001) when compared to healthy controls. There was no significant difference between biventricular ejection fraction between athletes and control subjects (p > 0.05). Cardiac MRI parameters, including left ventricle global longitudinal strain (LV-GLS), global circumferential strain (LV-GCS), and global radial strain (LV-GRS) values were normal but slightly lower in athletes compared to controls. LV-GCS and LV-GRS were significantly lower in athletes compared to controls (p = 0.007 and p = 0.005 respectively), but there was no significant difference for LV-GLS (p = 0.088). CONCLUSION: In this study of 122 athletes, there was no evidence of subclinical myocardial alterations following recovery from COVID-19 found on cardiac MRI strain analysis. When compared to healthy controls, the competitive athletes had higher end-diastolic volume indices and reduced, albeit normal, strain values of LV-GLS, LV-GCS, and LV-GRS.

Prevalence and significance of incidental findings on computed tomography pulmonary angiograms: A retrospective cohort study.

OBJECTIVE: The purpose of this study was to analyze the prevalence and significance of incidental findings on computed tomography pulmonary angiography (CTPA) studies and to assess the diagnostic yield of CTPA in identifying an alternate diagnosis to pulmonary embolism (PE) on PE negative exams. METHODS: All patients who had a CTPA exam for PE evaluation between Jan 2016 and Dec 2018 with a negative PE result were included in the study. A total of 2083 patients were identified. We retrospectively queried the electronic medical record and the radiology report and recorded the following: Age, Sex, BMI, Patient location and Incidental findings. The incidental findings were classified into type 1 (Alternate diagnosis other than PE which could explain the patient's symptoms), type 2 (non-emergent findings which needed further work up) and type 3 findings (non-emergent findings which did not need further work up). Logistic regression analysis was performed to determine what factors affected the probability of finding a type 1 incidental (alternate diagnosis) or a type 2 incidental. RESULTS: 74.5% of the patients in our study had at least one incidental finding. Type 1 incidental findings (alternate diagnosis to PE) were found in 864 patients (41.5%). The most common type 1 finding was pneumonia followed by fluid overload. Male sex, increased age and lower BMI were significantly associated with increased odds of a type 1 incidental(p < 0.05). Similarly, all the patient locations had significantly different odds of finding a type-1 incidental, with ICU having the highest odds, followed by inpatient, ED and outpatient locations (p < 0.05). 563 patients (27%) had at least one type 2 incidental findings and the most common type 2 findings were progressive lung malignancy/ metastatic disease and new pulmonary nodule. Increased age was significantly associated with the probability of a type 2 finding (p < 0.05). CONCLUSIONS: CTPA may suggest an alternative diagnosis to pulmonary embolism in approximately 40% of the patients with a negative study. The probability of finding an alternate diagnosis (type 1 incidental) is higher in elderly patients and in patients referred from ICU and inpatient units.

Current update on status of saline infusion sonohysterosalpingography.

The purpose of this article is to elucidate the current role of saline infusion sonohysterosalpingography (SIS) in evaluation of various uterine pathologies. SIS improves visualization of the endometrium and pathologies related to endometrial cavity, as well as it can simultaneously assess tubal patency. SIS provides high-resolution images, and three-dimensional (3D) reformatted images provide excellent orientation for radiologists as well as the clinicians about the underlying pathologies. This article will discuss imaging technique, indications, pearls, and pitfalls in imaging, diverse disease pathologies, and ultimately compare performance of SIS among other different imaging modalities. SIS as an adjunct imaging modality results in a greater diagnostic yield for diverse uterine pathologies.

Dual Energy CT Physics-A Primer for the Emergency Radiologist.

Dual energy CT (DECT) refers to the acquisition of CT images at two energy spectra and can provide information about tissue composition beyond that obtainable by conventional CT. The attenuation of a photon beam varies depends on the atomic number and density of the attenuating material and the energy of the incoming photon beam. This differential attenuation of the beam at varying energy levels forms the basis of DECT imaging and enables separation of materials with different atomic numbers but similar CT attenuation. DECT can be used to detect and quantify materials like iodine, calcium, or uric acid. Several post-processing techniques are available to generate virtual non-contrast images, iodine maps, virtual mono-chromatic images, Mixed or weighted images and material specific images. Although initially the concept of dual energy CT was introduced in 1970, it is only over the past two decades that it has been extensively used in clinical practice owing to advances in CT hardware and post-processing capabilities. There are numerous applications of DECT in Emergency radiology including stroke imaging to differentiate intracranial hemorrhage and contrast staining, diagnosis of pulmonary embolism, characterization of incidentally detected renal and adrenal lesions, to reduce beam and metal hardening artifacts, in identification of uric acid renal stones and in the diagnosis of gout. This review article aims to provide the emergency radiologist with an overview of the physics and basic principles of dual energy CT. In addition, we discuss the types of DECT acquisition and post processing techniques including newer advances such as photon-counting CT followed by a brief discussion on the applications of DECT in Emergency radiology.

The Renal Vasculature: What the Radiologist Needs to Know.

The physiologic role of the kidneys is dependent on the normal structure and functioning of the renal vasculature. Knowledge and understanding of the embryologic basis of the renal vasculature are necessary for the radiologist. Common anatomic variants involving the renal artery (supernumerary arteries and prehilar branching) and renal vein (supernumerary veins, delayed venous confluence, retroaortic or circumaortic vein) may affect procedures like renal transplantation, percutaneous biopsy, and aortic aneurysm repair. Venous compression syndromes (anterior and posterior nutcracker syndrome) can be symptomatic and can be diagnosed with a combination of radiologic features. Renal artery stenosis is commonly atherosclerotic and is diagnosed with Doppler US, CT angiography, or MR angiography. Fibromuscular dysplasia, the second most common cause of renal artery narrowing, has a characteristic string-of-beads appearance resulting from multifocal stenoses and dilatations. Manifestations of renal vasculitis differ depending on whether the affected vessels are large, medium, or small. Renal vascular injury is graded according to the American Association for the Surgery of Trauma (AAST) renal injury scale, which defines vascular injury and active bleeding in renal injuries. Both renal arteries and veins are affected by primary neoplasms or secondarily by neoplasms from adjacent structures. Differentiation between bland thrombus and tumor thrombus and the extent of involvement dictate management in malignancies, especially renal cell carcinoma. Aneurysms, pseudoaneurysms, arteriovenous malformations, and arteriovenous fistulas can affect renal vessels and can be diagnosed with specific imaging features. The radiologist has a critical role in identification of specific imaging characteristics and establishing the diagnosis in the varied pathologic conditions affecting the renal vasculature, which is critical for directing management. Thus, the renal vasculature should be an integral part of radiologists' checklist. ©RSNA, 2021.

Factors Affecting Radiation Dose in Computed Tomography Angiograms for Pulmonary Embolism: A Retrospective Cohort Study.

OBJECTIVES: Computed tomography pulmonary angiogram (CTPA) is one of the most commonly ordered and frequently overused tests. The purpose of this study was to evaluate the mean radiation dose to patients getting CTPA and to identify factors that are associated with higher dose. MATERIAL AND METHODS: This institutionally approved retrospective study included all patients who had a CTPA to rule out acute pulmonary embolism between 2016 and 2018 in a tertiary care center. Patient data (age, sex, body mass index [BMI], and patient location), CT scanner type, image reconstruction methodology, and radiation dose parameters (dose-length product [DLP]) were recorded. Effective dose estimates were obtained by multiplying DLP by conversion coefficient (0.014 mSv•mGy-1•cm-1). Multivariate logistic regression analysis was performed to determine the factors affecting the radiation dose. RESULTS: There were 2342 patients (1099 men and 1243 women) with a mean age of 58.1 years (range 0.2-104.4 years) and BMI of 31.3 kg/m2 (range 12-91.5 kg/m2). The mean effective radiation dose was 5.512 mSv (median - 4.27 mSv; range 0.1-43.0 mSv). Patient factors, including BMI >25 kg/m2, male sex, age >18 years, and intensive care unit (ICU) location, were associated with significantly higher dose (P < 0.05). CT scanning using third generation dual-source scanner with model-based iterative reconstruction (IR) had significantly lower dose (mean: 4.90 mSv) versus single-source (64-slice) scanner with filtered back projection (mean: 9.29 mSv, P < 0.001). CONCLUSION: Patients with high BMI and ICU referrals are associated with high CT radiation dose. They are most likely to benefit by scanning on newer generation scanner using advance model-based IR techniques.

Imaging of COVID-19 pneumonia: Patterns, pathogenesis, and advances.

COVID-19 pneumonia is a newly recognized lung infection. Initially, CT imaging was demonstrated to be one of the most sensitive tests for the detection of infection. Currently, with broader availability of polymerase chain reaction for disease diagnosis, CT is mainly used for the identification of complications and other defined clinical indications in hospitalized patients. Nonetheless, radiologists are interpreting lung imaging in unsuspected patients as well as in suspected patients with imaging obtained to rule out other relevant clinical indications. The knowledge of pathological findings is also crucial for imagers to better interpret various imaging findings. Identification of the imaging findings that are commonly seen with the disease is important to diagnose and suggest confirmatory testing in unsuspected cases. Proper precautionary measures will be important in such unsuspected patients to prevent further spread. In addition to understanding the imaging findings for the diagnosis of the disease, it is important to understand the growing set of tools provided by artificial intelligence. The goal of this review is to highlight common imaging findings using illustrative examples, describe the evolution of disease over time, discuss differences in imaging appearance of adult and pediatric patients and review the available literature on quantitative CT for COVID-19. We briefly address the known pathological findings of the COVID-19 lung disease that may help better understand the imaging appearance, and we provide a demonstration of novel display methodologies and artificial intelligence applications serving to support clinical observations.

Dynamic Contrast-Enhanced MRI-Upgraded Prostate Imaging Reporting and Data System Version 2 Category 3 Peripheral Zone Observations Stratified by a Size Threshold of 15 mm.

OBJECTIVE. The purpose of this study is to evaluate dynamic contrast-enhanced (DCE) MRI (DCE-MRI)-upgraded Prostate Imaging Reporting and Data System version 2 (PI-RADSv2) peripheral zone (PZ) observations stratified by a size threshold of 15 mm. MATERIALS AND METHODS. Two blinded radiologists independently assessed 301 patients with 326 clinically significant tumors (Gleason score [GS] ≥ 7) using multiparametric MRI performed before radical prostatectomy (RP) between 2012 and 2017 and then assigned PI-RADSv2 scores for the tumors. PI-RADSv2 category 3 PZ observations upgraded on the basis of abnormal DCE-MRI findings were tabulated, agreement was calculated, and discrepancies were resolved by consensus. The rate of detection of clinically significant cancer among upgraded observations was calculated. Size was measured at consensus review and was compared with pathologic outcomes on the basis of the PI-RADSv2 size threshold of 15 mm or more, with the use of chi-square tests. RESULTS. Reader 1 identified 5.2% (17/326) of DCE-MRI-upgraded PZ observations, and reader 2 identified 8.3% (27/326) of such observations. Interobserver agreement for PI-RADSv2 scoring was moderate (κ = 0.42) overall, but it was fair (κ = 0.23) when only DCE-MRI-upgraded observations were considered. Of the upgraded observations, which had a mean (± SD) size of 14 ± 6 mm (range, 6-29 mm), 10.4% (34/326) were agreed on after consensus review. Size smaller than 15 mm was noted for 61.8% (21/34) of observations. Among DCE-MRI-upgraded PZ observations, true- and false-positive detection rates for significant cancer were 91.2% (31/34) and 8.8% (3/34), respectively. Observations 15 mm or larger had no false-positive diagnoses and higher rates of extraprostatic extension (84.6% [11/13] vs 38.1% [8/21]; p = 0.016); however, there was no difference in GS (p = 0.354) compared with observations less than 15 mm in size. CONCLUSION. PZ observations upgraded on the basis of abnormal DCE-MRI findings have a high likelihood of being clinically significant cancer; however, agreement between readers was low. DCE-MRI-upgraded tumors of 15 mm or larger had no false-positive diagnoses and higher rates of extraprostatic extension, suggesting that they could be assigned to PI-RADSv2 assessment category 5.

Evaluation of a free-breathing respiratory-triggered (Navigator) 3-D T1-weighted (T1W) gradient recalled echo sequence (LAVA) for detection of enhancement in cystic and solid renal masses.

OBJECTIVES: To evaluate free-breathing Navigator-triggered 3-D T1-weighted MRI (NAV-LAVA) compared to breath-hold (BH)-LAVA among cystic and solid renal masses. MATERIALS AND METHODS: With an IRB waiver, 44 patients with 105 renal masses (71 non-enhancing cysts and 14 cystic and 20 solid renal masses) underwent MRI between 2016 and 2017 where BH-LAVA and NAV-LAVA were performed. Subtraction images were generated for BH-LAVA and NAV-LAVA using pre- and 3-min post-gadolinium-enhanced images and were evaluated by two blinded radiologists for overall image quality, image sharpness, motion artifact, and quality of subtraction (using 5-point Likert scales) and presence/absence of enhancement. Percentage signal intensity change (Δ%SI) = ([SI.post-gadolinium-SI.pre-gadolinium]/SI.pre-gadolinium)*100, was measured on BH-LAVA and NAV-LAVA. Likert scores were compared using Wilcoxon's sign-rank test and accuracy for detection of enhancement compared using receiver operator characteristic (ROC) analysis. RESULTS: Overall image quality (p = 0.002-0.141), image sharpness (p = 0.002-0.031), and motion artifact were better (p = 0.002) comparing BH-LAVA to NAV-LAVA for both radiologists; however, quality of image subtraction did not differ between groups (p = 0.09-0.14). Sensitivity/specificity/area under ROC curve for enhancement in cystic and solid renal masses using subtraction and %SIΔ were (1) BH-LAVA: 64.7%/98.6%/0.82 (radiologist 1), 61.8%/95.8%/0.79 (radiologist 2), and 70.6%/81.7%/0.76 (%SIΔ) versus 2) NAV-LAVA: 58.8%/95.8%/0.79 (radiologist 1, p = 0.16), 58.8%/88.7%/0.73 (radiologist 2, p = 0.37), and 73.5%/76.1%/0.75 (%SIΔ, p = 0.74). CONCLUSIONS: NAV-LAVA showed similar quality of subtraction and ability to detect enhancement compared to BH-LAVA in renal masses albeit with lower image quality, image sharpness, and increased motion artifact. NAV-LAVA may be considered in renal MRI for patients where BH is suboptimal. KEY POINTS: • Free-breathing Navigator (NAV) 3-D subtraction MRI is comparable to breath-hold (BH) images. • Accuracy for subjective and quantitative diagnosis of enhancement in renal masses on NAV 3-D T1W is comparable to BH MRI. • NAV 3-D T1W renal MRI is useful in patients who may not be able to adequately BH.

Encapsulating Peritoneal Sclerosis: The Abdominal Cocoon.

Encapsulating peritoneal sclerosis (EPS) is a rare but serious condition that results in (a) encapsulation of bowel within a thickened fibrocollagenous peritoneal membrane and (b) recurrent episodes of bowel obstruction. Although described by various names in the literature, the preferred term is encapsulating peritoneal sclerosis because it best describes the morphologic and histologic changes in this disorder. The etiology of EPS is multifactorial, with a wide variety of implicated predisposing factors that disrupt the normal physiologic function of the peritoneal membrane-prime among these factors being long-term peritoneal dialysis and bacterial peritoneal infections, especially tuberculosis. The clinical features of EPS are usually nonspecific, and knowledge of the radiologic features is necessary to make a specific diagnosis. The findings on radiographs are usually normal. Images from small-bowel follow-through studies show the bowel loops conglomerated in a concertina-like fashion with a serpentine arrangement in a fixed U-shaped configuration. US demonstrates a "cauliflower" appearance of bowel with a narrow base, as well as a "trilaminar" appearance depicted especially with use of high-resolution US probes. CT is the imaging modality of choice and allows identification of the thickened contrast material-enhanced abnormal peritoneal membrane and the encapsulated clumped bowel loops. In addition, CT can potentially help identify the cause of EPS (omental granuloma in tuberculosis), as well as the complications of EPS (bowel obstruction). Conservative medical treatment and surgical therapy early in the course of EPS have been used for management of the condition. The purpose of this article is to review the nomenclature and etiopathogenesis of EPS, describe the multimodality imaging appearances of EPS, including differentiating its features from those of other conditions mimicking EPS, and give an overview of management options. Online DICOM image stacks are available for this article. ©RSNA, 2018.

Diagnostic Accuracy of MRI for Detecting Inferior Vena Cava Wall Invasion in Renal Cell Carcinoma Tumor Thrombus Using Quantitative and Subjective Analysis.

OBJECTIVE: The purpose of this study is to evaluate MRI in inferior vena cava (IVC) renal cell carcinoma (RCC) tumor thrombus for the diagnosis of caval wall invasion. MATERIALS AND METHODS: This retrospective case-control study evaluated 24 consecutive patients who underwent thrombectomy for RCC IVC tumor thrombus (11 [45.8%] with invasion) seen at preoperative MRI. A blinded radiologist segmented tumor thrombus on apparent diffusion coefficient (ADC) maps and T2-weighted images for texture analysis, measured the diameter of the renal vein and IVC at the level of the renal vein ostium, and measured the craniocaudal extent and volume of the tumor thrombus. Two blinded radiologists independently evaluated the margin of the tumor thrombus (smooth vs irregular), thinning or thickening and abnormal T2-weighted signal or enhancement of the IVC wall, and overall impression of invasion. Comparisons were performed using logistic regression models and chi-square with accuracy calculated using ROC. RESULTS: Subjective features were associated with invasion (p = 0.001-0.045) with moderate-to-substantial agreement (κ = 0.49-0.66). The overall impression of invasion had a sensitivity of 63.6% (95% CI, 30.8-89.1%) and a specificity of 92.3% (95% CI, 64.0-99.8%) with perfect agreement (κ = 1.0). Tumor thrombus with invasion had larger diameters of renal vein (28 ± 8 vs 15 ± 6 mm; p = 0.031) and IVC (41 ± 9 vs 19 ± 6 mm; p = 0.003), greater craniocaudal extent (87 ± 34 vs 51 ± 31 mm; p = 0.0239), and greater volume (77.4 ± 57.6 vs 17.7 ± 17.4 cm3; p = 0.003) than did thrombi without invasion. The ROC AUC ranged from 0.78 to 0.83. ADC and texture parameters were not significantly different between groups (p = 0.208-0.503); however, larger entropy in invasive tumor thrombus trended toward significance (p = 0.061). A model combining volume, entropy, and overall impression achieved an AUC of 0.91 (95% CI, 0.77-1.0). CONCLUSION: The combination of tumor thrombus volume with entropy and subjective overall impression of IVC wall invasion achieved the highest accuracy for diagnosis.

Diagnostic Accuracy of MRI for Diagnosis of Internal Hernia in Pregnant Women With Prior Roux-en-Y Gastric Bypass.

OBJECTIVE: The purpose of this study was to evaluate the accuracy of MRI for the diagnosis of internal hernia (IH) in pregnant women who have undergone Roux-en-Y gastric bypass (RYGB). MATERIALS AND METHODS: Fifteen consecutively registered pregnant women (eight with surgically proven IH, seven without IH) who had previously undergone RYGB underwent MRI to rule out IH between July 2011 and July 2016. Two blinded radiologists retrospectively evaluated MRI examinations for the presence or absence of 13 established CT findings of IH. The final diagnosis of IH was evaluated subjectively and with two previously validated CT models (model 1, mesenteric swirl or small-bowel obstruction; model 2, beaking of the superior mesenteric vein or small-bowel obstruction). Diagnostic odds ratio (DOR) and interobserver agreement were calculated for each feature, and the subjective and model-based diagnoses of IH were compared by chi-square test. RESULTS: There were no statistically significant differences in patient age (p = 0.68), gestational age (p = 0.35), or time since RYGB (p = 0.55) between patients with and those without IH. The findings with best DOR and interobserver agreement were beaking of the superior mesenteric vein (reader 1 DOR, 39; reader 2 DOR, 39; κ = 1.00), mesenteric swirl (reader 1 DOR, 11; reader 2 DOR, 39; κ = 0.86), engorgement of mesenteric vessels (reader 1 DOR, 24; reader 2 DOR, 15; κ = 0.84), and mesenteric edema (reader 1 DOR, 11; reader 2 DOR, 3; κ = 0.73). The other findings had either low accuracy, poor interobserver agreement, or both. The overall sensitivity and specificity of the diagnosis of IH ranged from 75% to 88% and 86% to 100% for the two readers. There was no difference in diagnostic accuracy between the three methods (p = 0.93). CONCLUSION: MRI is useful in the diagnosis of IH in pregnant women who have undergone RYGB. The specificity is comparable to that of CT, and the sensitivity approaches that of CT.

Intraventricular migration of an isolated fourth ventricular cysticercus following cerebrospinal fluid shunting.

BACKGROUND: Isolated intraventricular neurocysticercosis (NCC) is less frequently seen and can be missed on plain magnetic resonance imaging (MRI). Three-dimensional constructive interference in steady state (CISS) sequence is an extremely helpful sequence in identifying the lesion but is rarely used routinely. CASE DESCRIPTION: Here, we report a case of young male adult who presented with diminution of vision and headache. MRI of the brain revealed hydrocephalus, and on using CISS sequence only, the lesion could be identified in the fourth ventricle. He was treated with medical management, and ventriculoperitoneal shunting of cerebrospinal fluid was done to relieve the hydrocephalus. It resulted in immediate relief with aggravation of headache few days later. Repeat MRI revealed intraventricular migration into the left foramen of monro leading to left lateral ventricle dilatation necessitating endoscopic removal of the lesion. CONCLUSION: CISS sequence is definitely the sequence of choice in identifying intraventricular NCC. Ventriculoperitoneal shunting can result in the intraventricular migration of the cyst due to sudden decompression necessitating repeat surgery. Endoscopic removal of NCC has a high success rate with limited complications.

Coexistent borderline serous cystadenoma with multifocal hydatidosis in a young female: lessons learnt.

Hydatid disease (HD) is a commonly occurring zoonotic disease caused by tapeworms of the genus Echinococcus. It is endemic in many parts of the world and can involve almost any organ of the body. Although HD of the liver and lungs is quite common, ovarian involvement is rare. We present a case of a 24-year-old female patient who was diagnosed with multifocal hydatidosis involving the liver and bilateral ovaries on imaging. Postoperative histopathology confirmed the hydatid disease in the liver and one ovary. However, the cystic lesion in the other ovary turned out to be a borderline serous cystadenoma. This case highlights the limitation of imaging in differentiating between simple hydatid cysts and serous cystadenomas of the ovaries. Another point we learnt is that even in the presence of multifocal hydatidosis in endemic regions, serous cystadenoma needs to be considered in imaging differential diagnosis.