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1.
Eur J Radiol ; 175: 111436, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38522396

RESUMO

PURPOSE: Patients with suspicion of clinically significant prostate cancer (csPC) on multiparametric prostate MRI (mpMRI) but negative or inconclusive MRI/US fusion-guided biopsy (FB) can be challenging in clinical practice. To assess the utility of MRI in-bore biopsy (IB) in patients with discordant imaging and histopathological findings after FB. METHODS: Consecutive patients with Prostate Imaging Reporting and Data System (PI-RADS) category 4 or 5 on mpMRI at 3T after FB without histologically confirmed csPC who underwent IB between 01/2014 and 05/2022, were retrospectively included. The primary objective was to assess the detection rate of csPC. Secondary objectives were to analyze clinical parameters, MRI parameters, and lesion localization. RESULTS: In the final cohort of 51 patients, the IB resulted in an overall detection rate of 71% for PC and 47% for csPC. Furthermore, in 55% of cases with initial low-grade PC, the Gleason score was upgraded after IB. CsPC was often detected apical and/or anterior. The detection rate for PC was 58% in PI-RADS category 4 and 94% in PI-RADS category 5 (csPC 39% and 61%, respectively). Patients with csPC had statistically significant smaller prostate volumes, a higher PI-RADS category, a higher prostate-specific antigen density (PSAD), and were older. CONCLUSIONS: For a relevant proportion of patients with PI-RADS category 4 or 5 and negative or inconclusive findings on previous FB, but with persistent suspicion of csPC, a subsequent IB verified the presence of csPC. Therefore, IB can be a backup in cases of uncertainty.


Assuntos
Biópsia Guiada por Imagem , Neoplasias da Próstata , Humanos , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Biópsia Guiada por Imagem/métodos , Idoso , Pessoa de Meia-Idade , Estudos Retrospectivos , Ultrassonografia de Intervenção , Imageamento por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Imagem por Ressonância Magnética Intervencionista/métodos , Imageamento por Ressonância Magnética Multiparamétrica/métodos , Reprodutibilidade dos Testes
2.
Abdom Radiol (NY) ; 47(7): 2486-2493, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35578110

RESUMO

PURPOSE: Analysis of patients with pre-operative 3 T multiparametric prostate MRI (mpMRI) to determine reliable MRI-based risk predictors of patients at risk for positive surgical margins (PSM) in robotic assisted radical prostatectomy (RPE). METHODS: Consecutive patients with 3 T mpMRI and subsequent RPE from 01/2015 to 12/2018 were retrospectively included. Patients were compared regarding clinical and MRI related parameters such as length of capsular tumor contact (LCC) and distance to the membranous urethra (UD). RESULTS: Forty-nine of 179 patients (27%) had PSM in 70 different localizations, with the majority located at the capsule (57%, 40/70), mostly apical and/or posterior. The second most often PSM occurred at the apical urethra (22%, 15/70). PCA was visible on mpMRI at the localization of PSM in 93% at the capsule and in 80% at the urethra. PSA, PI-RADS classification, extraprostatic extension (EPE), and seminal vesicles infiltration (SVI) on MRI were significantly higher / more frequent in patients with PSM. LCC (AUC 0.710), EPE (AUC 0.693), and UD (1-AUC 0.673) predicted PSM (overall). An UD of ≤ 3.5 mm showed the highest accuracy of 95% (J = 0.946) for PSM at the urethra and a LCC of ≥ 22.5 mm with 77% (J = 0.378) for PSM at the capsule. CONCLUSION: PSM occurred mostly in the apex and/or posteriorly at the capsule or at the apical urethra. LCC was the best MRI predictor for PSM at the capsule and UD for tumors with PSM at the apical urethra. Using these MRI parameters readers might pre-operatively determine PCA localizations at risk for PSM.


Assuntos
Neoplasias da Próstata , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Margens de Excisão , Prostatectomia/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Estudos Retrospectivos
3.
Eur Radiol ; 32(4): 2351-2359, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34748064

RESUMO

OBJECTIVES: T o evaluate the value of multiparametric MRI (mpMRI) for the prediction of prostate cancer (PCA) aggressiveness. METHODS: In this single center cohort study, consecutive patients with histologically confirmed PCA were retrospectively enrolled. Four different ISUP grade groups (1, 2, 3, 4-5) were defined and fifty patients per group were included. Several clinical (age, PSA, PSAD, percentage of PCA infiltration) and mpMRI parameters (ADC value, signal increase on high b-value images, diameter, extraprostatic extension [EPE], cross-zonal growth) were evaluated and correlated within the four groups. Based on combined descriptors, MRI grading groups (mG1-mG3) were defined to predict PCA aggressiveness. RESULTS: In total, 200 patients (mean age 68 years, median PSA value 8.1 ng/ml) were analyzed. Between the four groups, statistically significant differences could be shown for age, PSA, PSAD, and for MRI parameters cross-zonal growth, high b-value signal increase, EPE, and ADC (p < 0.01). All examined parameters revealed a significant correlation with the histopathologic biopsy ISUP grade groups (p < 0.01), except PCA diameter (p = 0.09). A mixed linear model demonstrated the strongest prediction of the respective ISUP grade group for the MRI grading system (p < 0.01) compared to single parameters. CONCLUSIONS: MpMRI yields relevant pre-biopsy information about PCA aggressiveness. A combination of quantitative and qualitative parameters (MRI grading groups) provided the best prediction of the biopsy ISUP grade group and may improve clinical pathway and treatment planning, adding useful information beyond PI-RADS assessment category. Due to the high prevalence of higher grade PCA in patients within mG3, an early re-biopsy seems indicated in cases of negative or post-biopsy low-grade PCA. KEY POINTS: • MpMRI yields relevant pre-biopsy information about prostate cancer aggressiveness. • MRI grading in addition to PI-RADS classification seems to be helpful for a size independent early prediction of clinically significant PCA. • MRI grading groups may help urologists in clinical pathway and treatment planning, especially when to consider an early re-biopsy.


Assuntos
Neoplasias da Próstata , Idoso , Estudos de Coortes , Humanos , Biópsia Guiada por Imagem , Imageamento por Ressonância Magnética/métodos , Masculino , Gradação de Tumores , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Estudos Retrospectivos
4.
Magn Reson Imaging ; 85: 3-9, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34655728

RESUMO

PURPOSE: To evaluate the feasibility of perfusion measurements in the human kidney by Fourier decomposition MRI (FD-MRI). METHODS: Renal perfusion measurements by FD-MRI and arterial spin labeling (ASL) were performed using a 1.5 T whole-body MR-scanner (Magnetom Avanto, Siemens Healthineers AG, Germany) in 15 healthy volunteers (mean age 33.0 ± 13.6 years). Five healthy volunteers were measured twice to evaluate the reproducibility. Besides, five patients with renal artery stenosis (RAS) (mean age 58.4 ± 16.2 years) were included in the study to evaluate potential clinical use of the FD-MRI for evaluating renal perfusion. For renal FD-MRI, coronal 2D-TrueFisp sequence (1 section; section thickness: 10 mm; FOV: 400 × 400 mm 2; TR/TE: 2.06/0.89 ms; 250 images; 0,36 s/image), for renal ASL, coronal FAIR-TrueFisp sequence (1 section; section thickness: 10 mm; FOV: 400 × 400 mm2; TR/TE 4.0/2.0 ms, TI 1200 ms, 30 averages; 8,32 s/average) were acquired without any triggering. Perfusion parameter maps of the kidneys were calculated for both methods. After manual segmentation, ROI-based analysis (whole kidney, cortex and medulla, respectively) was performed and the results were subsequently compared using the Student t-test. RESULTS: The acquisition times were 1.30 min and 4.16 min, for renal FD-MRI and ASL, respectively. No significant difference in global renal perfusion (RBF) between both methods was detected (mean RBF in the right kidney: 308.4 ± 31.5 mL/100 mL/min for FD-MRI; 315.2 ± 41.1 for ASL; in the left kidney: 315.6 ± 32.8 mL/100 mL/min for FD-MRI; 310.2 ± 39.1 mL/100 mL/min for ASL, respectively). The results indicated good reproducibility of both considered methods. However, cortico-medullar differentiation was not possible by FD-MRI, probably due to lower SNR compared to ASL. Significant difference in the side-separated RBF were measured by FD-MRI as well as by ASL (p < 0.05) in patients with RAS. CONCLUSIONS: FD-MRI is a novel, rapid approach for contrast-free perfusion quantification in the human kidney. Main advantage of this new method compared to ASL perfusion is the significant shorter acquisition time and lower dependency on patient's compliance. However, lower SNR of FD-MRI needs further improvement to make FD-MRI a competitive alternative to ASL.


Assuntos
Rim , Imageamento por Ressonância Magnética , Adulto , Idoso , Estudos de Viabilidade , Humanos , Rim/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Perfusão , Circulação Renal , Reprodutibilidade dos Testes , Marcadores de Spin , Adulto Jovem
5.
Eur J Radiol ; 147: 110110, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34952329

RESUMO

PURPOSE: This study investigates preoperative lymph node metastases (LNM) detection accuracy by MRI and CT in patients with prostate cancer (PCA). METHODS: All patients with preoperative MRI, CT or both and subsequent radical prostatectomy (RPE) and lymphadenectomy (LA) were included in this retrospective cohort study. Prostate specific antigen (PSA), PI-RADS, ISUP grade group, clinical and pathological tumor (T) stage was compared between negative and positive nodal (N) stage. LNM were assessed with size and localization and weather they were preoperatively detected or not. In patients with preoperative CT and MRI, the results were compared intermodally. The reference standard was the histopathological results after RPE and LA. RESULTS: A total of 228 patients were analysed including 24 patients with confirmed LNM (N1; 11%). PSA (median 9.7 vs. 14 ng/ml), PI-RADS (median 4 vs. 5), ISUP (median 2 vs. 4), and cT/pT-stage (median T2 vs. T3) was significantly higher in patients with LNM. No LNM were found in patients with ISUP-1-PCA. MRI was able to detect 67% of patients with LNM. Lymph node metastases presented on MRI predominantly small, round-shaped, located parailiacally with a minimum SAD of 4 mm (vs. CT SAD of 8 mm). In comparison, MRI was superior to CT in the detection of LNM (sensitivity 81% vs. 33%; specificity 99% vs. 97). CONCLUSION: LNM were very rare in patients with PSA < 10 ng/ml, PI-RADS ≤ 4, and ≤ cT2. MRI could detect LNM up to 4 mm with a moderate sensitivity and high specificity. Thus, MRI might optimise the preoperative diagnostic and therapy planning of patients with PCA, whereas CT was clearly limited for N-stage assessment.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Humanos , Metástase Linfática/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Prostatectomia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
6.
Abdom Radiol (NY) ; 46(6): 2751-2759, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33452898

RESUMO

OBJECTIVES: The aim of this study was to investigate 3 Tesla multiparametric magnetic resonance imaging (mpMRI)-based predictors for the pretherapeutic T staging of prostate cancer and their accuracy. METHODS: Consecutive patients with 3 Tesla mpMRI, positive systematic and MR-targeted biopsy, and subsequent radical prostatectomy (RPE) between 01/2016 and 12/2017 were included. MRI parameters such as measurable extraprostatic extension (EPE) (≥ 3 mm), length of (pseudo)capsular contact (LCC), invasion of neurovascular bundle (NVBI), and/or seminal vesicles lesion contact (SVC) or infiltration (SVI) were assessed and correlated to clinical and histopathological results. RESULTS: 136 men were included. In 76 cases, a pT2 stage was determined, in 29 cases a pT3a, and in 31 a pT3b stage. The positive and negative predictive values (PPV, NPV) for the detection of T3 by measurable EPE on MRI was 98% (CI 0.88-1) and 81% (CI 0.72-0.87). No visible NVBI was found in pT2 patients (NPV 100%; CI 0.95-1). ROC analysis for T3a prediction with LCC (AUC 0.81) showed a sensitivity of 87% and a specificity of 62% at a threshold of 12.5 mm (J = 0.485) and 93% and 58% at 11 mm (Jmax = 0.512). All patients with pT3a had a LCC > 5 mm. In case of pT3b, 29/31 patients showed a SVC (PPV 76%, CI 0.61-0.87; NPV 98%, CI 0.93-0.99), and 23/31 patients showed a SVI (PPV 100%, CI 0.86-1; NPV 93%, CI 0.87-0.96). EPE (p < 0.01), LCC (p = 0.05), and SVC (p = 0.01) were independent predictors of pT3. CONCLUSIONS: MRI-measurable EPE, LCC, and SVC were reliable, independent, preoperative predictors for a histopathological T3 stage. A LCC ≥ 11 mm indicated a pT3a stage, whereas a LCC < 5 mm excluded it. On MRI, visible SVI or even SVC of the PCa lesion was reliable preoperative predictors for a pT3b stage.


Assuntos
Prostatectomia , Neoplasias da Próstata , Humanos , Imageamento por Ressonância Magnética , Masculino , Estadiamento de Neoplasias , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Estudos Retrospectivos
7.
Eur Radiol ; 29(12): 6965-6970, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31250168

RESUMO

OBJECTIVES: To evaluate different analgesic techniques in MRI-guided in-bore prostate biopsy (IB-GB) regarding the influence on patient procedural experience of pain. METHODS: Two hundred fifty-two consecutive patients who had received an IB-GB either with intrarectal instillation of 2% lidocaine gel (n = 126, group A) or with periprostatic nerve block (PPNB) with 2% mepivacaine (n = 126, group B) were retrospectively included in this study. Pain scores were measured on a visual analog scale, the operating room time (ORT) was recorded for each biopsy and correlations between the parameters were analysed. RESULTS: Pain scores for IB-GB were slightly lower in group B compared with group A (2.0 ± 1.9; 2.4 ± 1.7; p = 0.02). In group A, significantly more targeted biopsy cores were acquired (group B: 5.2 ± 1.1; group A: 5.6 ± 0.8; p < 0.01). ORT was comparable and not significantly different in both groups. There was only a weak correlation between pain scores and ORT in group B (rS = 0.22; p = 0.01), but no correlation between pain scores and the number of biopsy cores or the prostate volume. CONCLUSIONS: Pain levels are generally low for MRI-guided in-bore biopsy using either PPNB or intrarectal instillation of lidocaine gel. A statistically significant, slightly lower pain score was documented for PPNB and might be preferred when the focus is analgesia. On the other hand, due to the minor difference and easier administration, intrarectal gel instillation seems to be a reasonable practice for standard analgesia for MRI-guided in-bore biopsy. KEY POINTS: • Pain levels were low for MRI-guided in-bore biopsy using either PPNB or intrarectal instillation of lidocaine gel as analgesic method. • PPNB prior to IB-GB resulted in a slightly lower pain score but required a higher effort. • Intrarectal gel anaesthesia seems to be a reasonable practice for standard analgesia for IB-GB in an outpatient setting.


Assuntos
Anestésicos Locais/administração & dosagem , Lidocaína/administração & dosagem , Mepivacaína/administração & dosagem , Dor/prevenção & controle , Próstata/patologia , Neoplasias da Próstata/patologia , Idoso , Idoso de 80 Anos ou mais , Analgesia/métodos , Biópsia com Agulha de Grande Calibre/efeitos adversos , Biópsia com Agulha de Grande Calibre/métodos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Bloqueio Nervoso/métodos , Duração da Cirurgia , Manejo da Dor , Medição da Dor , Estudos Retrospectivos
8.
Langmuir ; 27(3): 965-71, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21188992

RESUMO

Interfacial tension measurements have been performed at the water/hexane interface on mixtures of the bovine milk protein ß-lactoglobulin and positively charged cationic surfactants (alkytrimethylammonium bromides). The addition of surfactants with different chain lengths leads to the formation of protein-surfactant complexes with different adsorption properties as compared to those of the single protein. In this study, the formation of complexes has been observed clearly for protein-long chain surfactant (TTAB and CTAB) mixtures, which has shown in addition to specific electrostatic interactions the relevance of hydrophobic interactions between surfactant molecules and the protein. The modeling of interfacial tension data by using a mixed adsorption model provides a quantitative understanding of the mixture behavior. Indeed, the value of the adsorption constant of the protein obtained in the presence of surfactants has strongly varied as compared to the single protein. Actually, this parameter which represents the affinity of the molecule for the interface is representative of the hydrophobic character of the compound and so of its surface activity. Even if a more hydrophobic and more surface active protein-surfactant complex has been formed, the replacement of this complex from the interface by surfactants close to their cmc was observed.


Assuntos
Óleos/química , Proteínas/química , Tensoativos/química , Adsorção , Modelos Teóricos , Água/química
9.
Langmuir ; 26(20): 15901-8, 2010 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-20857971

RESUMO

Understanding the effects of digestion conditions on the structure of interfacial protein networks is important in order to rationally design food emulsions which can moderate lipid digestion. This study compares the effect of gastric conditions (pH, temperature, and ionic strength) on ß-lactoglobulin films at different fluid interfaces: air-water, tetradecane-water, and olive oil-water. The experiments have been designed to simulate the passage into the stomach media. Hence, preformed interfacial protein (ß-lactoglobulin) networks have been exposed to gastric conditions in order to establish generic aspects of the digestion process. The results show that the presence of an oil phase affects both the unfolding of the protein at the interface on adsorption and the subsequent interprotein associations responsible for network formation at the interface. Furthermore, the effects of the physiological conditions characteristic of the stomach also altered differently the preformed protein layer at different fluid interfaces. Initially, the effects of temperature, acid pH, and ionic strength on the dilatational modulus of ß-lactoglobulin adsorbed layers at tetradecane-water and olive oil-water interfaces were studied in isolation. The presence of salt was found to have a major effect on the dilatational response at the oil-water interface in contrast to the observations at the air-water interface: it enhanced intermolecular association, hence increasing the packing at the interface causing it to become more elastic. Exposure to acid pH (2.5) also increased the elasticity of the interface, possibly due to the fact that strong electrostatic interactions acting at the interface compensated for the reduced level of intermolecular association. However, the increase in dilatational modulus at the oil-water interface was less noticeable upon exposure to combined changes in acid pH and ionic strength, as would occur in the stomach. This is consistent with previously reported observations at the air-water interface. The quantitative differences in the response of the protein networks to gastric media at different fluid interfaces are discussed in terms of the conformation of ß-lactoglobulin within the networks formed at each interface based on detailed theoretical modeling of adsorption data.


Assuntos
Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Lactoglobulinas/química , Óleos/química , Óleos/farmacologia , Estômago/química , Temperatura , Adsorção , Animais , Bovinos , Concentração de Íons de Hidrogênio , Concentração Osmolar , Conformação Proteica/efeitos dos fármacos , Água/química
10.
J Phys Chem B ; 113(3): 745-51, 2009 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-19113874

RESUMO

The adsorption behavior of the beta-lactoglobuline has been studied in the presence of the anionic surfactant sodium dodecylsulfate (SDS) and compared for two different interfaces, water/air and water/hexane. The fitting of experimental data (adsorption isotherms) by a mixed adsorption model and the determination of structural parameters such as the molecular area occupied by the protein-surfactant complex and the surfactant molecules at the interface allowed to have a better understanding of the composition and as a consequence the behavior of the mixed interfacial layer. The parameters obtained for the mixtures are similar to those obtained separately for the single components, but the comparison of the both interfaces has shown significant differences. Much higher concentration of complex is found at the water/hexane interface, which is the result of a better affinity of the protein for this interface. A higher penetration of the protein into the oil phase and the presence of interactions between protein-surfactant complexes and free surfactant molecules stabilize the interface preventing its replacement by the SDS molecules. Rheological experiments show a decrease of the visco-elastic modulus at both interfaces with increasing SDS concentration. But at the water/oil interface, contrary to the water/air interface at which the replacement of the protein has been clearly observed, this decrease is attributed to changes of complex properties. At high SDS concentrations, an increase of the hydrophilic character due to hydrophobic interactions with the surfactant molecules leads to an increase in the mobility of the complex, which favors its desorption upon increased competition by the surfactant.


Assuntos
Lactoglobulinas/química , Óleos/química , Dodecilsulfato de Sódio/química , Água/química , Adsorção , Algoritmos , Animais , Bovinos , Elasticidade , Hexanos/química , Leite/química , Modelos Moleculares , Modelos Estatísticos , Proteínas/química , Reologia , Solubilidade , Solventes , Tensão Superficial , Viscosidade
11.
Presse Med ; 13(1): 33-7, 1984 Jan 14.
Artigo em Francês | MEDLINE | ID: mdl-6231544

RESUMO

In this review paper the respective places of microsurgery and in vitro fertilization in the treatment of tubal infertility are evaluated. The best and current results of the two methods are compared and their future is considered. Most of the indications for microsurgery remain, while some (e.g. poor prognosis salpingostomy, repeated tuboplasty, tubal transplantation) require discussion and new ones are appearing. The advent of in vitro fertilization has introduced some technical changes in surgery of the ovaries and surrounding tissues and has given rise to new techniques. It has also modified the initial investigations in infertile women and the use of pre-operative and second-look laparoscopy. It has exerted little influence on microsurgeons specialized in problems of reproduction but has obliged their teams to be reorganized on a multidisciplinary basis in order to cope with new techniques.


Assuntos
Doenças das Tubas Uterinas/complicações , Fertilização in vitro , Infertilidade Feminina/terapia , Microcirurgia , Doenças das Tubas Uterinas/cirurgia , Feminino , Humanos , Infertilidade Feminina/etiologia , Infertilidade Feminina/cirurgia
12.
Acta Eur Fertil ; 14(1): 17-22, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6675380

RESUMO

The places microsurgery and in vitro fertilization (IVF) hold, respectively, in the treatment of tubal infertility are evaluated. "Optimal" and "acceptable" results of the two techniques are compared, and future results are talked about. Most of the indications for microsurgery are still valid, some are debatable (salpingostomies with bad prognosis, repeated surgery, tubal transplant, etc.), and some new ones emerge. Technically speaking, IVF introduces some changes in surgery of the ovary and surrounding tissues and gives rise to new techniques. Diagnostic and therapeutic management is changed insofar as initial assessment, preoperative coelioscopy and, above all, postoperative monitoring are concerned. The microsurgeon, who is to remain a reproduction specialist, undergoes few personal changes, but his team must be organized on a multi-field basis in order to cope with the new techniques.


Assuntos
Doenças das Tubas Uterinas/terapia , Fertilização in vitro/métodos , Infertilidade Feminina/terapia , Microcirurgia/métodos , Terapia Combinada , Transferência Embrionária , Feminino , Humanos , Complicações Pós-Operatórias/etiologia , Gravidez , Prognóstico
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