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1.
J Comput Assist Tomogr ; 46(6): 862-870, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36194830

RESUMO

PURPOSE: The aim of the study was to compare diagnostic accuracy of dual-energy computed tomography (DECT) and magnetic resonance imaging (MRI) to detect enhancement in renal masses. METHODS: Adults renal masses of 10 mm or greater with both fast kilovoltage potential switching DECT and contrast-enhanced MRI performed within 12 months were retrospectively included. Two blinded radiologists independently evaluated for enhancement subjectively (5-point Likert scales) and quantitatively (signal intensity ratio ≥15% for MRI, iodine concentration ≥1.2 or ≥2.0 mg/mL for DECT). Per-lesion diagnostic accuracy, with histologic reference standard for solid masses, was expressed as the area under the receiver operator curve (AUC) for each index test. Differences were evaluated for statistical significance using the DeLong test. RESULTS: We included 24 patients with 41 masses: 17 solid renal masses and 24 Bosniak 1 or 2 cysts. There was no significant difference in diagnostic accuracy comparing subjective enhancement by MRI and using iodine overlay DECT for reader 1 (AUC 0.99 vs 0.99, P = 0.38) or reader 2 (AUC 1.00 vs 0.94, P = 0.12) Interobserver agreement was κ = 0.61 for DECT and κ = 0.71 for MRI. There was no significant difference either in accuracy between quantitative assessment using signal intensity ratio or iodine concentration for reader 1 (AUC 0.94 vs 0.94, P = 0.88) or reader 2 (AUC 0.97 vs 0.92, P = 0.16). False-negative results in both subjective and quantitative assessment were nearly exclusively seen in papillary renal cell carcinoma, occurring with both DECT and MRI. CONCLUSIONS: We detected no significant differences in accuracy for detecting enhancement in renal masses comparing MRI and DECT. Our results require further investigation in larger sample sizes, but suggest that DECT may be comparable to MRI for detection of enhancement in renal masses.


Assuntos
Iodo , Imagem Radiográfica a Partir de Emissão de Duplo Fóton , Humanos , Adulto , Meios de Contraste , Tomografia Computadorizada por Raios X/métodos , Estudos Retrospectivos , Sensibilidade e Especificidade , Imageamento por Ressonância Magnética/métodos , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos
3.
J Magn Reson Imaging ; 55(1): 265-274, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34223675

RESUMO

BACKGROUND: Diffusion weighted imaging (DWI) is fundamental for prostate cancer (PCa) detection with MRI; however, limited by susceptibility artifact from hip prosthesis. PURPOSE: To evaluate image quality and ability to detect PCa with quantitative T2-mapping and DWI in men with hip prosthesis undergoing prostate MRI. STUDY TYPE: Prospective, cross-sectional study. POPULATION: Thirty consecutive men with hip replacement (18 unilateral, 12 bilateral) undergoing prostate MRI from 2019 to 2021. FIELD STRENGTH/SEQUENCE: 3-T; multiparametric MRI (T2W, DCE-MRI, echo-planar [EPI]-DWI), T2-mapping (Carr-Purcell-Meiboom-Gill), FOCUS-EPI-DWI, PROPELLER-DWI. ASSESSMENT: Five blinded radiologists independently evaluated MRI image quality using a 5-point Likert scale. PI-RADS v2.1 scores were applied in four interpretation strategies: 1) T2W-FSE+DCE-MRI+EPI-DWI, 2) T2W-FSE+DCE-MRI+EPI-DWI+FOCUS-EPI-DWI, 3) T2W-FSE+DCE-MRI+EPI-DWI+PROPELLER-DWI, 4) T2W-FSE+DCE-MRI+EPI-DWI+T2-maps. Five-point confidence scores were recorded. STATISTICAL ANALYSIS: ANOVA, Kruskal-Wallis with pair-wise comparisons by Wilcoxon sign-rank, and paired t-tests, P < 0.05 was considered significant. Cohen's Kappa (k) for PI-RADSv2.1 scoring and proportion of correctly classified lesions tabulated for pathology-confirmed cases with 95% confidence intervals (CIs). RESULTS: For all radiologists, T2-map image quality was significantly higher than EPI-DWI, FOCUS-EPI-DWI, and PROPELLER-DWI and similar (P = 0.146-0.706) or significantly better (for two readers) than T2W-FSE and DCE-MRI. PI-RADS v2.1 agreement improved comparing strategy A (k = 0.46) to strategy B (k = 0.58) to strategy C (k = 0.58) and was highest with strategy D which included T2-maps (k = 1.00). Radiologists' confidence was significantly highest with strategy D. Strategies B and C had similar confidence (P = 0.051-0.063) both significantly outperforming strategy A. Twelve men with 17 lesions had pathology confirmed diagnoses (13 PCa, 4 benign). Strategy D had the highest proportion of correctly classified lesions (76.5-82.4%) with overlapping 95% confidence intervals. DATA CONCLUSION: T2-mapping may be a valuable adjunct to prostate MRI in men with hip replacement resulting in improved image quality, higher reader confidence, interobserver agreement, and accuracy in PI-RADS scoring. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY STAGE: 2.


Assuntos
Prótese de Quadril , Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Estudos Transversais , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudos Prospectivos , Próstata , Neoplasias da Próstata/diagnóstico por imagem
4.
Can Assoc Radiol J ; 73(2): 346-354, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34404240

RESUMO

PURPOSE: To compare 5 different rectal preparation strategies for prostate MRI. METHODS: This 5-arm quality-assurance study evaluated 56 patients per arm (280 patients) including: no preparation, clear-fluids diet (CFD) beginning at 00:00 hours on the day of MRI, Fleet®-enema, enema + CFD, enema + CFD + IV-antispasmodic agent. The study was powered to 0.80 with alpha-error of 0.05. Three blinded radiologists independently evaluated T2-Weighted (T2W) and Diffusion Weighed Imaging (DWI) for: rectal diameter (maximal AP diameter), rectal content (stool, fluid, gas), rectal motion, T2W/DWI image quality, T2W image sharpness and DWI susceptibility artifact using 5-point Likert scales. Overall comparisons were performed using analysis of variance (ANOVA) and Kruskal-Wallis, with pair-wise comparisons using paired t-tests and Wilcoxon sign-rank tests. RESULTS: Rectal diameter and amount of gas were lower in enema compared to non-enema groups (p < 0.001), with smallest diameter and least gas in the enema + CFD + IV-antispasmodic group (p = 0.022-<0.001). T2W image quality and sharpness were highest in the enema + CFD groups (p < 0.001) with no difference comparing enema + CFD with/without IV-antispasmodic (p = 0.064, 0.084). Motion artifact was least in enema + CFD + IV-antispasmodic group compared to all other groups (p < 0.001), followed by the enema + CFD group (p = 0.008-<0.001). DWI image quality was highest (p < 0.001) and DWI susceptibility artifact lowest (p < 0.001) in the enema + CFD groups (p < 0.001) and did not differ comparing enema + CFD with/without anti-spasmodic (p = 0.058-0.202). CONCLUSIONS: Use of enema + clear-fluids diet before prostate MRI yields the highest T2W and DWI image quality with the least DWI artifact. IV-antispasmodic use reduces motion on T2W but does not improve image quality on T2W or DWI, or lessen DWI artifact compared to enema + clear-fluids diet.

5.
Cureus ; 13(11): e19548, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34917432

RESUMO

To compare the efficacy of mechanical and chemical prophylaxis in non-surgically mechanically ventilated patients in terms of reduction in mortality and length of hospital stay. A total of 200 patients admitted to intensive care units (ICUs) were recruited retrospectively. Half participants received mechanical prophylaxis and half received chemical prophylaxis. Patients with medical diseases with age 18 years or above, both genders, Pakistani nationals, receiving mechanical ventilation for more than 48 hours or receiving subcutaneous low molecular weight (LMW) heparin or subcutaneous unfractionated heparin were included. Cases who undergone surgery and were then admitted to ICU, those who received both mechanical and chemical therapies, and patients who received anticoagulant treatment before admission to ICU were excluded from the study. The patient's age, gender, length of stay in ICU, and mortality were recorded in each group. Chi-square test was used to compare categorical data and Student t-test for continuous variables. The mean age was 55.51±8.37 years. The males were 108(54%) and females were 92(46%). The mortality rate was higher in the mechanical prophylaxis group (49%) than chemical (31%) statistically significantly (P=0.014). Similarly, the length of hospital stay was also higher in the mechanical prophylaxis group (7.27±0.897 days) than chemical (6.67±1.045) statistically (P<0.001). Chemical prophylaxis can reduce mortality and length of hospital stay more effectively than mechanical prophylaxis in ICUs admitted patients.

6.
Med Phys ; 48(11): 6889-6900, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34418108

RESUMO

PURPOSE: Accurate detection of transition zone (TZ) prostate cancer (PCa) on magnetic resonance imaging (MRI) remains challenging using clinical subjective assessment due to overlap between PCa and benign prostatic hyperplasia (BPH). The objective of this paper is to describe a deep-learning-based framework for fully automated detection of PCa in the TZ using T2-weighted (T2W) and apparent diffusion coefficient (ADC) map MR images. METHOD: This was a single-center IRB-approved cross-sectional study of men undergoing 3T MRI on two systems. The dataset consisted of 196 patients (103 with and 93 without clinically significant [Grade Group 2 or higher] TZ PCa) to train and test our proposed methodology, with an additional 168 patients with peripheral zone PCa used only for training. We proposed an ensemble of classifiers in which multiple U-Net-based models are designed for prediction of TZ PCa location on ADC map MR images, with initial automated segmentation of the prostate to guide detection. We compared accuracy of ADC alone to T2W and combined ADC+T2W MRI for input images, and investigated improvements using ensembles over their constituent models with different methods of diversity in individual models by hyperparameter configuration, loss function and model architecture. RESULTS: Our developed algorithm reported sensitivity and precision of 0.829 and 0.617 in 56 test cases containing 31 instances of TZ PCa and in 25 patients without clinically significant TZ tumors. Patient-wise classification accuracy had an area under receiver operator characteristic curve (AUROC) of 0.974. Single U-Net models using ADC alone (sensitivity 0.829, precision 0.534) outperformed assessment using T2W (sensitivity 0.086, precision 0.081) and assessment using combined ADC+T2W (sensitivity 0.687, precision 0.489). While the ensemble of U-Nets with varying hyperparameters demonstrated the highest performance, all ensembles improved PCa detection compared to individual models, with sensitivities and precisions close to the collective best of constituent models. CONCLUSION: We describe a deep-learning-based method for fully automated TZ PCa detection using ADC map MR images that outperformed assessment by T2W and ADC+T2W.


Assuntos
Imageamento por Ressonância Magnética , Neoplasias da Próstata , Estudos Transversais , Imagem de Difusão por Ressonância Magnética , Humanos , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Estudos Retrospectivos
7.
Abdom Radiol (NY) ; 46(11): 5386-5407, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34245341

RESUMO

Ablative (percutaneous and stereotactic) thermal and radiotherapy procedures for management of both primary and metastatic renal cell carcinoma are increasing in popularity in clinical practice. Data suggest comparable efficacy with lower cost and morbidity compared to nephrectomy. Ablative therapies may be used alone or in conjunction with surgery or chemotherapy for treatment of primary tumor and metastatic disease. Imaging plays a crucial role in pre-treatment selection and planning of ablation, intra-procedural guidance, evaluation for complications, short- and long-term post-procedural surveillance of disease, and treatment response. Treatment response and disease recurrence may differ considerably after ablation, particularly for stereotactic radiotherapy, when compared to conventional surgical and chemotherapies. This article reviews the current and emerging role of imaging for ablative therapy of renal cell carcinoma.


Assuntos
Carcinoma de Células Renais , Ablação por Cateter , Neoplasias Renais , Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/cirurgia , Humanos , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/cirurgia , Recidiva Local de Neoplasia , Nefrectomia , Resultado do Tratamento
8.
J Clin Diagn Res ; 11(9): TD03-TD04, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29207807

RESUMO

Cystic lymphangiomas are usually congenital malformations of draining lymphatic channels with most common sites including neck, axilla, mediastinum and retroperitoneum. Occurrence of lymphangiomas in scrotum or inguinal region is a rare entity and epididymal origin of these lesions is even more infrequent. We herein report a case of epididymal lymphangioma detected on USG, which developed after surgical abdominal lymph nodal dissection in an adult patient of carcinoma rectum presenting as painless scrotal swelling.

9.
J Obes ; 2016: 1937320, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28116148

RESUMO

Background. In clinical practice, serum ferritin is used as a screening tool to detect iron deficiency. However, its reliability in obesity has been questioned. Objectives. To investigate the role of ferritin in overweight and obese people, either as a marker of inflammation or iron deficiency. Methods. On the basis of body mass index (BMI), 150 participants were divided into three equal groups: A: BMI 18.5-25 kg/m2, B: BMI 25-30 kg/m2, and C: BMI > 30 kg/m2. Serum iron, total iron binding capacity (TIBC), transferrin saturation, ferritin, C-reactive protein, and hemoglobin (Hb) were measured for each participant and analyzed through SPSS version 16. One-way ANOVA and Pearson's correlation tests were applied. Results. Ferritin was the highest in group C (M = 163.48 ± 2.23, P < 0.001) and the lowest in group A, (M = 152.78 ± 1.81, P < 0.001). Contrarily to ferritin, transferrin was the lowest in group C, (M = 30.65 ± 1.39, P < 0.001) and the highest in group A, (M = 38.66 ± 2.14, P < 0.001). Ferritin had a strong positive correlation with both BMI (r = 0.86, P < 0.001) and CRP (r = 0.87, P < 0.001) and strong negative correlation with Hb, iron, TIBC, and transferrin saturation (P < 0.001). Conclusion. Ferritin is a marker of inflammation rather than iron status in overweight and obese people. Complete iron profile including transferrin, rather than serum ferritin alone, can truly predict iron deficiency in such people.


Assuntos
Biomarcadores/sangue , Ferritinas/sangue , Obesidade Mórbida/sangue , Adolescente , Adulto , Idoso , Anemia Ferropriva/sangue , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
10.
An Bras Dermatol ; 90(1): 96-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25672304

RESUMO

Pigmented purpuric dermatoses are chronic and relapsing disorders characterized by a symmetrical rash of petechial and pigmentary macules, mainly confined to the lower limbs. Purpura annularis telangiectodes of Majocchi is a less common variant of Pigmented purpuric dermatoses characterized by punctate telangiectatic macules progressing to annular, hyperpigmented patches with central clearing and infrequent atrophy. A 12 year-old girl presented with asymptomatic round to oval reddish brown macules, present symmetrically over her lower and upper limbs for 3 years. Few lesions were annular in shape. Biopsy from the lesion was compatible with Pigmented purpuric dermatoses. On the basis of clinical and histopathological findings, a diagnosis of Purpura annularis telangiectodes of Majocchi was made. The patient began phototherapy thrice a week and showed excellent response.


Assuntos
Terapia PUVA/métodos , Transtornos da Pigmentação/tratamento farmacológico , Púrpura/tratamento farmacológico , Telangiectasia/tratamento farmacológico , Biópsia , Criança , Feminino , Humanos , Dermatoses da Perna/tratamento farmacológico , Dermatoses da Perna/patologia , Transtornos da Pigmentação/patologia , Púrpura/patologia , Doses de Radiação , Telangiectasia/patologia , Resultado do Tratamento
11.
An. bras. dermatol ; 90(1): 96-99, Jan-Feb/2015. graf
Artigo em Inglês | LILACS | ID: lil-735742

RESUMO

Pigmented purpuric dermatoses are chronic and relapsing disorders characterized by a symmetrical rash of petechial and pigmentary macules, mainly confined to the lower limbs. Purpura annularis telangiectodes of Majocchi is a less common variant of Pigmented purpuric dermatoses characterized by punctate telangiectatic macules progressing to annular, hyperpigmented patches with central clearing and infrequent atrophy. A 12 year-old girl presented with asymptomatic round to oval reddish brown macules, present symmetrically over her lower and upper limbs for 3 years. Few lesions were annular in shape. Biopsy from the lesion was compatible with Pigmented purpuric dermatoses. On the basis of clinical and histopathological findings, a diagnosis of Purpura annularis telangiectodes of Majocchi was made. The patient began phototherapy thrice a week and showed excellent response.


Assuntos
Criança , Feminino , Humanos , Terapia PUVA/métodos , Transtornos da Pigmentação/tratamento farmacológico , Púrpura/tratamento farmacológico , Telangiectasia/tratamento farmacológico , Biópsia , Dermatoses da Perna/tratamento farmacológico , Dermatoses da Perna/patologia , Transtornos da Pigmentação/patologia , Púrpura/patologia , Doses de Radiação , Resultado do Tratamento , Telangiectasia/patologia
12.
J Coll Physicians Surg Pak ; 24(4): 224-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24709231

RESUMO

OBJECTIVE: To develop and validate a food frequency table (FFQ) for use in urban Pakistani population. STUDY DESIGN: A validation study. PLACE AND DURATION OF STUDY: The Aga Khan University, Karachi, from June to November 2008. METHODOLOGY: Healthy adult females, aged ³ 18 years who consented to be included in the study were inducted, while males, unhealthy females, aged below 18 years or who did not consent were excluded. The FFQ was administered once while 4, 24 hours recalls spread over a period of one year were administered as the reference method. Daily intakes for energy, protein, fat, and calcium intake were estimated for both the tools. Crude and energy adjusted correlations for nutrient intakes were computed for the FFQ and mean of 4, 24 hours recalls and serum N-telopeptide of type-I collagen (NTx). RESULTS: The correlation coefficients for the FFQ with mean of 4, 24 hours recall ranged from 0.21 for protein to 0.36 for calcium, while the correlation for nutrient estimates from the FFQ with NTx ranged from -0.07 for calcium to 0.01 for energy. CONCLUSION: Highly significant correlations were found for nutrient intakes estimated from the FFQ vs. those estimated from the mean of 4, 24 hours recalls but no correlations was found between nutrient estimates from the FFQ and serum NTx levels. FFQ was concluded to be a valid tool for assessing dietary intake of adult females in Pakistan.


Assuntos
Cálcio/administração & dosagem , Ingestão de Energia , Inquéritos e Questionários , Adolescente , Adulto , Colágeno Tipo I/análise , Proteínas Alimentares/administração & dosagem , Feminino , Humanos , Masculino , Rememoração Mental , Pessoa de Meia-Idade , Avaliação Nutricional , Paquistão , Peptídeos/análise , Reprodutibilidade dos Testes , Fatores Socioeconômicos , População Urbana , Adulto Jovem
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