Diffusion weighted MRI in evaluation of transplanted kidney: Preliminary clinical experience

Purpose: To evaluate the diagnostic performance ofDiffusion Weighted (DW) magnetic resonance(MR) imaging in evaluation of transplantedkidneys.Patients and methods: One hundred twelve patientswith transplanted kidney from live kidney donorswere evaluated with coronal T2w and DW MRI ofthe kidney. There was 86 males and 26 females andthe mean age was 26.911.5ys (range 10-55).Apparent diffusion coefficient (ADC) wascalculated and the kidneys studied for any areasdiffusion restriction. Our patients classified into 2groups: Group 1 included 81 patients with stablekidney function and normal serum creatinine andthe second group included 31 patients with alteredkidney function, it includes 18 patients with chronicnephropathies and 13 patients with acute cellularrejection.Results: The mean ADC values for group 1 was2.70.26 x 10-3 mm2 /sec (range 1.93-3.6). In casesof chronic nephropathies, the mean ADC valueswas 2.30.22mm2/sec (range 2.05-2.77) while incases of acute cellular rejection it was1.80.2mm2/sec (range 1.7-2.2). When we use the2.4mm2/sec as a low cutoff ADC value fordiagnosis of normal kidney function, the sensitivity,specificity and overall accuracy for DWI MRI was80%, 96% and 93.5% respectively.When we used the ADC value of 2mm2/sec as acutoff value between acute cellular rejection andchronic nephropathies, the sensitivity, specificityand overall accuracy of DWI MRI was 90%, 98%and 90% respectively.Conclusion: In this relatively large study includingstable and abnormal function in transplantedkidneys, we can conclude that DW MRI isrelatively a new technique that allows diagnosis oftransplanted kidney with normal and alteredfunction

Adrenal Hemangioma: Findings at Multidetector CT with Short Review of the Literature

We present the computed tomography (CT) imaging findings of a 44-year-old male with incidentally discovered right adrenal hemangioma displaying imaging pattern of nonadenomatous pattern, associated with multiple hepatic hemangiomata using 64-slice multidetector scanner with reviewing published CT imaging findings with short review of the literature

Primary Adenocarcinoma in a Seminal Vesicular Cyst: A Case Report

Introduction: Primary adenocarcinoma of the seminal vesicle (SVC) is very rare. Presentation to the case: Herein, we reported a case of SVA of SV cyst arising in a 51-year-old deaf mute male patient. Laboratory parameters including serum prostate specific antigen (PSA) level were normal. Contrast-enhanced magnetic resonance imaging demonstrated large reterovesical cystic lesion with mural nodules. The patient was managed by radical prostatectomy and seminovesiculolectomy.  Microscopic examination revealed well-differentiated primary mucinous adenocarcinoma of left seminal vesicle cyst.   Conclusion: To the best of our knowledge, this was the first case of SVA of SV cyst arising in deaf mute patient

Static T2w MRU in Noncalcular Urinary Obstruction: Comparison of Its Two Techniques

The purpose of this study was to compare the diagnostic accuracy of T2-weighted (T2w) MR urography (MRU) techniques — the standard MRU using fast spin echo (FSE) and postprocessing maximum intensity projection (MIP) and the single-shot MRU — in the diagnosis of ureteric obstruction in patients with noncalcular urinary obstruction. The study included 150 patients admitted to our center between January 2005 and December 2006. There were 203 renal units with noncalcular obstruction; 53 patients had bilateral obstruction. Patients with calcular obstruction were excluded. There were 85 males and 65 females with a mean age of 50 (range: 5–83) years. All patients were examined with static MRU using both single-shot (thick slab) and multisection MRU. Using single-shot MRU, we obtained images at the direct coronal and oblique coronal, as well as sagittal, planes for each renal unit. Postprocessing MIP for the standard coronal heavy T2 source images to obtain coronal and oblique images was done. Among the obstructed 203 units, the intrinsic causes were present in 157 units (151 were stricture and six were ureteric tumors), while the extrinsic causes were present in 46 units (35 bladder tumor, four ureterocele, five retroperitoneal fibrosis, one prostatic tumor, and one local pelvic recurrence after radical cystectomy for bladder cancer). The overall accuracy of single-shot MRU was 89% and was 93% for the multisection MRU in cases of intrinsic ureteric obstruction, while in cases of extrinsic obstruction, it was 20% for single-shot MRU and 96% for multisection MRU. T2w static MRU is a very useful technique in diagnosing noncalcular ureteric obstruction. Multisection MRU has a high diagnostic accuracy and reliability over that of the single-shot technique. The single-section technique is very rapid and useful in diagnosing ureteric stricture so it could be used as a localizer, while multisection images with postprocessing MIP is mandatory, especially in cases of suspected ureteric tumors or extraureteric causes

Primary Mucinous Carcinoma of Cowper' gland: A Case Report of a Rare Variant

Introduction: Primary carcinomas of the bulbourethral glands (Cowper’s glands) are extremely rare.Presentation of case: Herein, a 57-year-old man was presented by perineal mass for seven years. Physical examination revealed a nontender stony hard perineal mass without signs of inflammation. A urethrogram showed compression of the anterior part of the bulbous urethra. MRI of the mass revealed large perineal multilocular and marginal enhancement. The patient was managed by excision of the mass with safety margin. Histopathological examination of the mass showed remnants of malignant acini floating in pools of mucin which formed about 80% of tumor tissue Immunohistochemical analysis revealed positive reactions of the tumour cells with cytokeratin 20 but negative reactions for PSA, β-catenin and cytokeratin 7.Conclusion: We reported the first case of primary mucinous carcinoma arising in the Cowper’s glands and the 22nd in the literature of Cowper’s gland carcinoma

Automatic Detection of 2D and 3D Lung Nodules in Chest Spiral CT Scans

Automatic detection of lung nodules is an important problem in computer analysis of chest radiographs. In this paper, we propose a novel algorithm for isolating lung abnormalities (nodules) from spiral chest low-dose CT (LDCT) scans. The proposed algorithm consists of three main steps. The first step isolates the lung nodules, arteries, veins, bronchi, and bronchioles from the surrounding anatomical structures. The second step detects lung nodules using deformable 3D and 2D templates describing typical geometry and gray-level distribution within the nodules of the same type. The detection combines the normalized cross-correlation template matching and a genetic optimization algorithm. The final step eliminates the false positive nodules (FPNs) using three features that robustly define the true lung nodules. Experiments with 200 CT data sets show that the proposed approach provided comparable results with respect to the experts

Early Assessment of Acute Renal Rejection Post-transplantation: A Combined Imaging and Clinical Biomarkers Protocol

© 2018 IEEE. Non-invasive evaluation of renal transplant function is crucial. Hence, a computer-assisted diagnostic (CAD) system is introduced in this paper to evaluate kidney function post-transplantation. The developed CAD system integrates clinical-based with diffusion weighted (DW) MR image-based biomarkers. The latter are derived from 3D DW-MRIs at multiple strengths and duration of the magnetic field (i.e. b-values). These DW-MRI scans were acquired at multiple geographical areas (Egypt and USA) using different scanner types (GE and Philips). The developed CAD system first segments kidneys using level-sets method and then estimates the DW-MRI image-markers, known as apparent diffusion coefficients (ADCs), from the segmented kidney. Then, the clinical biomarkers (serum creatinine and creatinine clearance) are integrated with the DW-MR image-markers (ADCs) resulted in new integrated markers known as integrated ADCs (IADCs). These IADCs are then used to construct cumulative distribution functions (CDFs) at multiple b-values. Finally, these markers (i.e. CDFs of the IADCs) are used to assess renal transplant status using different classifiers. Our CAD system demonstrates an almost consistent accuracy of 93%, sensitivity of 93%, and specificity of 92% in distinguishing acute rejection (AR) from non-rejection (NR) renal transplants, making the proposed diagnostic platform independent from the geographical area, scanner type, and classifier. These promising preliminary results are of high diagnostic accuracy and suggest that the developed CAD system might be noninvasively able to diagnose renal allograft status

DWI-MRI: Single, Informative, and Noninvasive Technique for Prostate Cancer Diagnosis

Aim. To evaluate diffusion weighted image-MRI (DWI) as a single diagnostic noninvasive MRI technique for prostate cancer (PCa) diagnosis. Material and Methods. A prospective study was conducted between July 2008 and July 2009. Candidates patients were equal or more than 40 years old, with suspicious digital rectal examination (more than clinical T2) or PSA >4 ng/mL. Informed consent was signed. DWI-MRI was performed at 1.5 T with a body coil combined with a spine coil in consecutive 100 cases. The histopathology of biopsies has been used as reference standard. Two examiners were evaluating MRI and TRUS, both of them were blinded regarding pathological findings. Accuracy, specificity, and sensitivity were statistically analyzed. Results. Based on pathological diagnosis: group A (cancerous); 75 cases and group B (non-cancerous); 25 cases. Mean age was 65.3 and 62.8 years in groups A and B, respectively. Mean PSA was 30.7 and 9.2 ng/mL in groups A and B, respectively. Sensitivity of DWI was 58.3% while specificity was 83.8%. Accuracy of lesion detection was 52.4–77.8% (P < 0.05). Moreover, DWI at ADC value 1.2 × 10−3 mL/sec could determine 82.4% of true positive cases (P < 0.05). ADC values were lower with Gleason score ≥7 (P < 0.05). Conclusion. DWI could represent a non invasive single diagnostic tool not only in detection and localization but also in prediction of Gleason score whenever DWI is used prior to invasive TRUS biopsy. Furthermore, targeted single biopsy could be planned after DWI to minimize patient morbidity by invasive techniques

Computer-Aided Diagnostic System for Early Detection of Acute Renal Transplant Rejection Using Diffusion-Weighted MRI

© 1964-2012 IEEE. Objective: Early diagnosis of acute renal transplant rejection (ARTR) is critical for accurate treatment. Although the current gold standard, diagnostic technique is renal biopsy, it is not preferred due to its invasiveness, long recovery time (1-2 weeks), and potential for complications, e.g., bleeding and/or infection. Methods: This paper presents a computer-aided diagnostic (CAD) system for early ARTR detection using (3D + b-value) diffusion-weighted (DW) magnetic resonance imaging (MRI) data. The CAD process starts from kidney tissue segmentation with an evolving geometric (level-set-based) deformable model. The evolution is guided by a voxel-wise stochastic speed function, which follows from a joint kidney-background Markov-Gibbs random field model accounting for an adaptive kidney shape prior and on-going kidney-background visual appearances. A B-spline-based three-dimensional data alignment is employed to handle local deviations due to breathing and heart beating. Then, empirical cumulative distribution functions of apparent diffusion coefficients of the segmented DW-MRI at different b-values are collected as discriminatory transplant status features. Finally, a deep-learning-based classifier with stacked nonnegative constrained autoencoders is employed to distinguish between rejected and nonrejected renal transplants. Results: In our initial \u27leave-one-subject-out\u27 experiment on 100 subjects, 97.0% of the subjects were correctly classified. The subsequent four-fold and ten-fold cross-validations gave the average accuracy of 96.0% and 94.0%, respectively. Conclusion: These results demonstrate the promise of this new CAD system to reliably diagnose renal transplant rejection. Significance: The technology presented here can significantly impact the quality of care of renal transplant patients since it has the potential to replace the gold standard in kidney diagnosis, biopsy

Role of magnetic resonance imaging in characterization of cystic renal lesions based on Bosniak classification version 2019

Abstract Background In 2019, the Bosniak classification system for cystic renal lesions underwent modifications aimed at addressing the limitations of the original classification. Results The revised 2019 version demonstrated notable differences from its predecessor. Specifically, it showed an increased proportion of class IIF cystic lesions (31% compared to 16.7%) and a decreased proportion of class III cystic lesions (27.4% compared to 45.2%). Additionally, the malignancy rate for class III cystic renal lesions was lower in the 2019 version (37.8% vs. 42.2%). When it came to diagnosing malignancies, the 2019 version exhibited higher specificity (74.4% compared to 41.03%) while maintaining a comparable sensitivity (97.8% vs. 100%) compared to the original Bosniak system. Conclusions The Bosniak 2019 version demonstrated enhanced specificity and diagnostic accuracy for malignancies in comparison to the original Bosniak system, all while maintaining an equivalent sensitivity