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Dive into the research topics where Jelena Djokić Kovač is active.

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Featured researches published by Jelena Djokić Kovač.


European Journal of Radiology | 2012

Diffusion-weighted MRI versus transient elastography in quantification of liver fibrosis in patients with chronic cholestatic liver diseases

Jelena Djokić Kovač; Marko Daković; Dejana Stanisavljevic; Tamara Alempijevic; Rada Jesic; Petar Seferovic; Ružica Maksimović

PURPOSE To evaluate the diagnostic value of diffusion-weighted magnetic resonance imaging (DWMRI) and transient elastography (TE) in quantification of liver fibrosis in patients with chronic cholestatic liver diseases. MATERIALS AND METHODS Forty-five patients underwent DWMRI, TE, and liver biopsy for staging of liver fibrosis. Apparent diffusion coefficient (ADC) was calculated for six locations in the liver for combination of five diffusion sensitivity values b=0, 50, 200, 400 and 800 s/mm(2). A receiver operating characteristic (ROC) analysis was performed to determine the diagnostic performance of DWMRI and TE. Segmental ADC variations were evaluated by means of coefficient of variation. RESULTS The mean ADCs (× 10(-3)mm(2)/s; b=0-800 s/mm(2)) were significantly different at stage F1 versus F ≥ 2 (p<0.05) and F2 versus F4. However, no significant difference was found between F2 and F3. For prediction of F ≥ 2 and F ≥ 3 areas under the ROC curves were 0.868 and 0.906 for DWMRI, and 0.966 and 0.960 for TE, respectively. The sensitivity and specificity were 90.9% and 89.3% for F ≥ 2 (ADC ≤ 1.65), and 92.3% and 92.1% for F ≥ 3 (ADC ≤ 1.63). Segmental ADC variation was lowest for F4 (CV=9.54 ± 6.3%). CONCLUSION DWMRI and TE could be used for assessment of liver fibrosis with TE having higher diagnostic accuracy and DWMRI providing insight into liver fibrosis distribution.


Medical Science Monitor | 2014

Intracranial arterial variations: A comprehensive evaluation using CT angiography

Jelena Djokić Kovač; Ana Stanković; Danilo Stanković; Bojan Kovač; Djordjije Saranovic

Background Intracranial arterial variations are a frequent finding in the general population. Knowledge of these vascular variations has significant clinical impact because some of them predispose patients to development of an aneurysm or cerebrovascular ischemic disease. The purpose of this study was to evaluate the frequency of intracranial vascular variations and associated vascular lesions on computed tomography angiography (CTA) examinations. Material/Methods CTA examinations performed by 16-detector computed tomography were prospectively reviewed in 455 patients for the presence of fenestrations, duplications, hypoplasia, aplasia, aneurysms, and other vascular lesions. Results Arterial fenestrations were found in 2.4% of patients, with the vertebrobasilar system as the most common location. The remaining fenestrations were located on the middle cerebral artery M1 segment (0.2%), anterior communicating artery (0.4%), and anterior cerebral artery A1 segment (0.6%). No associated aneurysms were noted in these patients. The prevalence of an azygos anterior cerebral artery was 1.5%. Bihemispheric anterior cerebral artery was found in 0.9%, hypoplastic A1 segment in 17.6%, and congenital absence of A1 segment in 0.4% of patients. Fetal origin of the posterior cerebral artery was found in 37% of cases. Hypoplastic vertebral artery terminating as posterior inferior cerebellar artery was observed in 9 patients, while transversal anastomosis between vertebral arteries was seen in only 1 patient. Conclusions CTA precisely demonstrates the diversity of intracranial arterial variations, whose overall frequency in this study is similar to previous radiological reports. Furthermore, our results do not show significant association between the frequency of aneurysms and cerebral arterial anomalies.


Acta Radiologica | 2013

MR imaging of primary sclerosing cholangitis: additional value of diffusion-weighted imaging and ADC measurement.

Jelena Djokić Kovač; Rada Jesic; Dejana Stanisavljevic; Bojan Kovač; Ružica Maksimović

Background Primary sclerosing cholangitis (PSC) is a cholestatic liver disease with chronic inflammation and progressive destruction of biliary tree. Magnetic resonance (MR) examination with diffusion-weighted imaging (DWI) allows analysis of morphological liver parenchymal changes and non-invasive assessment of liver fibrosis. Moreover, MR cholangiopancreatography (MRCP), as a part of standard MR protocol, provides insight into bile duct irregularities. Purpose To evaluate MR and MRCP findings in patients with primary sclerosing cholangitis and to determine the value of DWI in the assessment of liver fibrosis. Material and Methods The following MR findings were reviewed in 38 patients: abnormalities in liver parenchyma signal intensity, changes in liver morphology, lymphadenopathy, signs of portal hypertension, and irregularities of intra- and extrahepatic bile ducts. Apparent diffusion coefficient (ADC) was calculated for six locations in the liver for b = 800 s/mm2. Results T2-weighted hyperintensity was seen as peripheral wedge-shaped areas in 42.1% and as periportal edema in 28.9% of patients. Increased enhancement of liver parenchyma on arterial-phase imaging was observed in six (15.8%) patients. Caudate lobe hypertrophy was present in 10 (26.3%), while spherical liver shape was noted in 7.9% of patients. Liver cirrhosis was seen in 34.2% of patients; the most common pattern was micronodular cirrhosis (61.5%). Other findings included lymphadenopathy (28.9%), signs of portal hypertension (36.7%), and bile duct irregularities (78.9%). The mean ADCs (×10-3mm2/s) were significantly different at stage I vs. stages III and IV, and stage II vs. stage IV. No significant difference was found between stages II and III. For prediction of stage ≥II and stage ≥III, areas under receiver-operating characteristic curves were 0.891 and 0.887, respectively. Conclusion MR with MRCP is a necessary diagnostic procedure for diagnosis of PSC and evaluation of disease severity. Moreover, DWI could be used in continuation with standard MR sequences for the evaluation of liver fibrosis stage and distribution.


Journal of Breast Cancer | 2011

Invasive Lobular Breast Cancer Presenting an Unusual Metastatic Pattern in the Form of Peritoneal and Rectal Metastases: A Case Report

Djordjije Saranovic; Jelena Djokić Kovač; Srbislav Knezevic; Snezana Susnjar; Aleksandra Stefanović; Dragana Sobic Saranovic; Vera Artiko; Vladimir Obradovic; D. Masulovic; Marjan Micev; Pesko P

Gastrointestinal metastases from invasive lobular breast cancer are uncommon with the stomach and small intestines being the most common metastatic sites. Peritoneal and rectal metastases are very rare and only rarely occur as the first manifestation of disease. We herein report the case of a 47-year-old woman who presented with abdominal carcinomatosis as a first sign of invasive lobular breast carcinoma (ILC). Identifying the most important immunohistochemical markers for ILC: gross cystic disease fluid protein 15, estrogen and progesterone receptors enabled a correct diagnosis. After a six year disease-free period, relapse occurred with severe obstruction due to rectal metastasis from lobular breast carcinoma. Since there was no widespread metastatic disease, surgery with concomitant hormonal therapy was performed.


Auris Nasus Larynx | 2014

MRI in evaluation of neoplastic invasion into preepiglottic and paraglottic space

Bojan Banko; Vojko Djukic; Jovica Milovanovic; Jelena Djokić Kovač; Zorica Novakovic; Ruzica Maksimovic

OBJECTIVE The purpose of this study was to evaluate whether magnetic resonance (MR) imaging can accurately predict invasion of the preepiglottic and paraglottic space in patients with laryngeal carcinoma. Identification of these fat filling spaces is important for surgical treatment and prognosis. MATERIALS AND METHODS The study was based on the prospective analysis of MRI images in a series of 40 patients (90% males), overall average age 60.1 ± 7.3 years, (49-70 years), with histopathologically diagnosed laryngeal squamous cell carcinoma. Unenhanced T2w, T2w FS, T1w, and contrast-enhanced T1w FS scans were analyzed for the presence of preepiglottic and paraglottic neoplastic invasion and were compared to postoperative histopathologic analysis. RESULTS In 28 patients (70%) the tumor was glottic and in 12 patients (30%) supraglottic. No statistical difference was found in the number of patients with positive MRI findings in comparison to postsurgical patohistology for infiltration of the preepiglottic space (23% vs 20%, respectively). Sensitivity for infiltration of preepiglottic space was 89% and specificity was 97%. However, infiltration of the paraglottic spaces was observed more frequently on MRI than on postsurgical patohistology analysis (60% vs 40%, respectively; p<0.05), with a sensitivity of 67% and a specificity 50%. According to MRI findings, 26 (65%) patients were classified as T3, 14 (35%) patients as T2 while according to histopathologic analysis of specimens after surgery, 19 patients were classified as T3 (48%) and 21 as T2 (52%). CONCLUSION MRI has been shown to be a reliable method for assessment of preepiglottic space while the diagnostic accuracy in patients with infiltration of the paraglottic space is limited.


Acta Radiologica | 2016

Endometrioid adenocarcinoma of the ovary: MRI findings with emphasis on diffusion-weighted imaging for the differentiation of ovarian tumors

Jelena Djokić Kovač; Milan Terzic; Milan Mirković; Bojan Banko; Aleksandra Đikić-Rom; Ružica Maksimović

Background Preoperative differentiation of ovarian malignant tumors still remains a challenge. Diffusion-weighted imaging (DWI) provides information about cellularity of the lesion and might facilitate discrimination between different malignant ovarian lesions. Purpose To evaluate magnetic resonance imaging (MRI) findings of endometrioid adenocarcinoma of the ovary and to determine the value of DWI in the differential diagnosis of malignant and benign adnexal tumors. Material and Methods The following MRI findings were reviewed in 162 patients (21 endometrioid adenocarcinoma, 103 other malignant tumors, 38 benign tumors): lesion size, morphological appearance, T2-weighted (T2W) signal intensity, T1-weighted (T1W) signal intensity, contrast-enhancement pattern, DWI signals with apparent diffusion coefficient (ADC) calculated for b = 800 s/mm2 in solid tumor components. Results The most common morphological appearance was predominantly cystic lesion, found in 90.3% of patients with endometriod adenocarcinoma. The solid parts were slightly hyperintense on T2W images in 19 patients with marked enhancement after contrast administration. No significant difference (P = 0.13) in conventional MRI features was found between endometrioid adenocarcinoma and other malignant ovarian tumors. Hyperintensity on DWI was more frequently observed in malignant tumors than in benign lesions (P < 0.001). ADC values were significantly lower in endometrioid adenocarcinoma than other malignant tumors (0.79 ± 0.21 vs. 0.90 ± 0.19; P = 0.04) and in all malignant lesions compared with benign tumors (0.88 ± 0.31 vs. 1.33 ± 0.17; P < 0.001). Conclusion DWI with ADC measurement could indicate the presence of endometrioid adenocarcinomas due to a slightly but significantly lower ADC values compared to other malignant ovarian lesions. Thus, DWI is beneficial and should be part of a standard protocol for the evaluation of indeterminate adnexal lesions.


Japanese Journal of Radiology | 2012

Magnetic resonance imaging features of multiple duodenal lipomas: a rare cause of intestinal obstruction

Jelena Djokić Kovač; Marija Kratovac Dunjić; Milos Bjelovic; Bojan Banko; Gordana Lilić; Radovan Milenković; Marjan Micev; Ruzica Maksimovic

A 65-year-old man was evaluated because of vomiting and epigastric pain. The patient underwent upper gastrointestinal endoscopy and endoscopic ultrasound examination and was found to have multiple polypoid lesions in the D1 and D2 portions of the duodenum, causing almost complete obstruction of the duodenal lumen. The lesions were hyperintense on T1-weighted and intermediately intense on T2-weighted images, with a drop in signal on T1- and T2-weighted fat-suppressed images, consistent with a diagnosis of duodenal lipomas. Pathohistological examination confirmed the diagnosis of duodenal lipomas.


Cancer management and research | 2018

Preoperative neutrophil-to-lymphocyte ratio as a prognostic predictor after curative-intent surgery for hepatocellular carcinoma: experience from a developing country

Danijel Galun; Aleksandar Bogdanovic; Jelena Djokić Kovač; Predrag Bulajic; Zlatibor Loncar; Marinko Zuvela

Purpose The aim of the study was to evaluate a prognostic value of preoperative neutrophil-to-lymphocyte ratio (NLR) on long-term survival of cirrhotic and noncirrhotic hepatocellular cancer (HCC) patients managed by a curative-intent liver surgery in a developing country. Patients and methods During the study period between November 1, 2001, and December 31, 2012, 109 patients underwent potentially curative hepatectomy for HCC. Data were retrospectively reviewed from the prospectively collected database. The median follow-up was 25 months. NLR was estimated by dividing an absolute neutrophil count by an absolute lymphocyte count from the differential blood count. Receiver operating characteristic curve was constructed to assess the ability of NLR to predict long-term outcomes and to determine an optimal cutoff value for all patients group, the subgroup with cirrhosis, and the subgroup without cirrhosis. The optimal cutoff values were 1.28, 1.28, and 2.09, respectively. Results The overall 3- and 5-year survival rates were 49% and 45%, respectively, for low NLR group and 38% and 26%, respectively, for high NLR group. The difference was statistically significant (p=0.015). Overall survival was similar between low and high NLR groups in patients with cirrhosis; no difference was found between the groups (p=0.124). In patients without cirrhosis, low NLR group had longer overall survival compared with high NLR group (p=0.015). Univariate analysis identified four factors as significant predictors of long-term survival: cirrhosis, Child-Pugh score, platelet count, and NLR. On multivariate analysis, only platelet count and NLR were independent prognostic factors of long-term survival. Conclusion Prognostic value of NLR was confirmed in noncirrhotic HCC patients who underwent curative-intent liver surgery. In HCC patients with cirrhosis, the prognostic role of NLR was not confirmed.


Academic Radiology | 2018

The Time to and Type of Pancreatic Cancer Recurrence after Surgical Resection: Is Prediction Possible?

Jelena Djokić Kovač; Philipp Mayer; Thilo Hackert; Miriam Klauss

RATIONALE AND OBJECTIVES To evaluate factors predicting pancreatic cancer recurrence, and to determine the most common appearance of tumor relapse. MATERIALS AND METHODS Ninety patients with recurrent pancreatic cancer were retrospectively included in the study. 74.4% had pancreatic head tumors (group 1) and 25.6% pancreatic body and/or tail tumor (group 2). The tumor localization, operative technique, TNM stage, the R-status, tumor grade, lymphovascular, and perineural invasion were recorded. Location of local tumor recurrence, lymph node recurrence, or organ metastases were analyzed on the basis of follow-up CT imaging. RESULTS Mean recurrence time was 17.4 ± 13.2 months. The most common recurrence type was local recurrence (84.4%), followed by lymph node (15.5%), liver (14.4%), and lung metastasis (6.7%). The predominant site of local recurrence in pancreatic head tumors was close to superior mesenteric artery, common hepatic artery, and/or celiac artery (57.4%), followed by area defined by portal vein, inferior vena cava, CA or superior mesenteric artery (31.2%). Patients with pancreatic body and/or tail carcinoma had higher incidence (p = 0.003) of metastatic disease comparing to pancreatic head tumors, while resection margin was the most common type of local tumor recurrence, seen in 46.7% cases versus 8.2% of patients with pancreatic head tumors (p < 0.001). CONCLUSION The most common recurrence type in patients with resected pancreatic carcinoma was local recurrence along cardinal arteries. The localization of primary tumor influences the type of tumor relapse and site of local recurrence.


Acta Radiologica | 2017

Intrahepatic mass-forming cholangiocarcinoma and solitary hypovascular liver metastases: is the differential diagnosis using diffusion-weighted MRI possible?

Jelena Djokić Kovač; Danijel Galun; Aleksandra Đurić-Stefanović; Gordana Lilić; Dragan Vasin; Ljubica Lazić; D. Masulovic; Đorđije Šaranović

Background Intrahepatic mass-forming cholangiocellular carcinoma (IMC) is the second most common primary liver tumor. The differentiation between IMC and solitary hypovascular liver metastases (SHLM) represents a diagnostic challenge due to many overlapping magnetic resonance imaging (MRI) features. Purpose To determine the value of diffusion-weighted imaging (DWI) in addition to conventional MRI for the distinction between intrahepatic mass-forming cholangiocarcinoma and solitary hypovascular liver metastases. Material and Methods Fifty-three patients with pathologically proven IMC (n = 31) and SHLM (n = 22) who had undergone MRI and DWI before surgery or percutaneous biopsy were enrolled in this study. The following MRI features were analyzed: the size and shape of the lesion, presence of capsular retraction and segmental biliary dilatation, T2-weighted (T2W) signal intensity, the presence of target sign on DWI and enhancement pattern. Apparent diffusion coefficient (ADC) values were calculated for each lesion (b = 800 s/mm2). Univariate and multivariate logistic regression analyses were used to identify significant differentiating features between IMCs and SHLMs. Results Univariate analysis revealed that following parameters favor diagnosis of IMCs over SHLMs: lobulating shape, heterogeneous T2W signal intensity, capsular retraction, segmental biliary dilatation, target sign on DWI and rim-like enhancement on arterial phase followed by progressive enhancement in delayed phases. ADC values measured in the periphery of the lesion were significantly lower in IMCs in comparison to SHLMs. Multivariate analysis revealed that target sign on DWI was the most significant predictor of IMCs. Conclusion Qualitative DWI analysis with target sign significantly improves diagnostic accuracy for differentiation among IMC and SHLM lesions.

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Bojan Banko

University of Belgrade

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Bojan Kovač

Military Medical Academy

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Rada Jesic

University of Belgrade

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