Performance of an ultra-fast deep-learning accelerated MRI screening protocol for prostate cancer compared to a standard multiparametric protocol

OBJECTIVES

To establish and evaluate an ultra-fast MRI screening protocol for prostate cancer (PCa) in comparison to the standard multiparametric (mp) protocol, reducing scan time and maintaining adequate diagnostic performance.

MATERIALS AND METHODS

This prospective single-center study included consecutive biopsy-naïve patients with suspected PCa between December 2022 and March 2023. A PI-RADSv2.1 conform mpMRI protocol was acquired in a 3 T scanner (scan time: 25 min 45 sec). In addition, two deep-learning (DL) accelerated sequences (T2- and diffusion-weighted) were acquired, serving as a screening protocol (scan time: 3 min 28 sec). Two readers evaluated image quality and the probability of PCa regarding PI-RADSv2.1 scores in two sessions. The diagnostic performance of the screening protocol with mpMRI serving as the reference standard was derived. Inter- and intra-reader agreements were evaluated using weighted kappa statistics.

RESULTS

We included 77 patients with 97 lesions (mean age: 66 years; SD: 7.7). Diagnostic performance of the screening protocol was excellent with a sensitivity and specificity of 100%/100% and 89%/98% (cut-off ≥ PI-RADS 4) for reader 1 (R1) and reader 2 (R2), respectively. Mean image quality was 3.96 (R1) and 4.35 (R2) for the standard protocol vs. 4.74 and 4.57 for the screening protocol (p < 0.05). Inter-reader agreement was moderate (κ: 0.55) for the screening protocol and substantial (κ: 0.61) for the multiparametric protocol.

CONCLUSION

The ultra-fast screening protocol showed similar diagnostic performance and better imaging quality compared to the mpMRI in under 15% of scan time, improving efficacy and enabling the implementation of screening protocols in clinical routine.

CLINICAL RELEVANCE STATEMENT

The ultra-fast protocol enables examinations without contrast administration, drastically reducing scan time to 3.5 min with similar diagnostic performance and better imaging quality. This facilitates patient-friendly, efficient examinations and addresses the conflict of increasing demand for examinations at currently exhausted capacities.

KEY POINTS

Time-consuming MRI protocols are in conflict with an expected increase in examinations required for prostate cancer screening. An ultra-fast MRI protocol shows similar performance and better image quality compared to the standard protocol. Deep-learning acceleration facilitates efficient and patient-friendly examinations, thus improving prostate cancer screening capacity.

A Machine Learning Framework Reduces the Manual Workload for Systematic Reviews of the Diagnostic Performance of Prostate Magnetic Resonance Imaging

Prostate magnetic resonance imaging has become the imaging standard for prostate cancer in various clinical settings, with interpretation standardized according to the Prostate Imaging Reporting and Data System (PI-RADS). Each year, hundreds of scientific studies that report on the diagnostic performance of PI-RADS are published. To keep up with this ever-increasing evidence base, systematic reviews and meta-analyses are essential. As systematic reviews are highly resource-intensive, we investigated whether a machine learning framework can reduce the manual workload and speed up the screening process (title and abstract). We used search results from a living systematic review of the diagnostic performance of PI-RADS (1585 studies, of which 482 were potentially eligible after screening). A naïve Bayesian classifier was implemented in an active learning environment for classification of the titles and abstracts. Our outcome variable was the percentage of studies that can be excluded after 95% of relevant studies have been identified by the classifier (work saved over sampling: WSS@95%). In simulation runs of the entire screening process (controlling for classifier initiation and the frequency of classifier updating), we obtained a WSS@95% value of 28% (standard error of the mean ±0.1%). Applied prospectively, our classification framework would translate into a significant reduction in manual screening effort.

Patient summary

Systematic reviews of scientific evidence are labor-intensive and take a lot of time. For example, many studies on prostate cancer diagnosis via MRI (magnetic resonance imaging) are published every year. We describe the use of machine learning to reduce the manual workload in screening search results. For a review of MRI for prostate cancer diagnosis, this approach reduced the screening workload by about 28%.

Prediction of upgrade to clinically significant prostate cancer in patients under active surveillance: performance of a fully automated AI-algorithm for lesion detection and classification

BACKGROUND

Multiparametric MRI (MpMRI) improves the detection of aggressive prostate cancer (PCa) subtypes. As cases of active surveillance (AS) increase and tumor progression triggers definitive treatment, we evaluated whether an AI-driven algorithm can detect clinically significant PCa (csPCa) in patients under AS.

METHODS

Consecutive patients under AS who received mpMRI (PI-RADSv2.1 protocol) and subsequent MR-guided ultrasound fusion (targeted and extensive systematic) biopsy between 2017 and 2020 were retrospectively analyzed. Diagnostic performance of an automated clinically certified AI-driven algorithm was evaluated on both lesion and patient level regarding the detection of csPCa.

RESULTS

Analysis of 56 patients resulted in 93 target lesions. Patient level sensitivity and specificity of the AI algorithm was 92.5%/31% for the detection of ISUP ≥ 1 and 96.4%/25% for the detection of ISUP ≥ 2, respectively. The only case of csPCa missed by the AI harbored only 1/47 Gleason 7a core (systematic biopsy; previous and subsequent biopsies rendered non-csPCa).

CONCLUSIONS

AI-augmented lesion detection and PI-RADS scoring is a robust tool to detect progression to clinically significant PCa in patients under AS. Integration in the clinical workflow can serve as reassurance for the reader and streamline reporting, hence improve efficiency and diagnostic confidence. This article is protected by copyright. All rights reserved.

Association between global longitudinal strain and myocardial fibrosis biomarkers in patients with end-stage chronic kidney disease

Introduction

Myocardial fibrosis represents a landmark characteristic of uremic cardiomyopathy, leading to a high burden of arrhythmias, diastolic dysfunction (DD) and ultimately heart failure in this population. Collagen-derived biomarkers (Procollagen type I carboxy-terminal propeptide (PICP), Procollagen type III N-terminal peptide (P3NP)) and Galectin-3 (Gal-3) are associated with the extent of myocardial fibrosis on myocardial biopsy. Global longitudinal strain (GLS) as assessed by two-dimensional speckle tracking echocardiography (2D-STE) has been shown to detect subclinical myocardial dysfunction in various populations. The correlation between GLS and the serum level of these biomarkers has not been studied so far.

Purpose

The aim of this study was to evaluate the association between the left ventricular GLS measured by 2D-STE and the serum level of three biomarkers (PICP, P3NP, Gal-3) known to be associated with the presence of myocardial fibrosis, in patients with end-stage renal disease (ESRD), not on dialysis.

Methods

We conducted a cross-sectional study that included 135 patients with an eGFR (CKD-EPI) &lt;15 ml/min/1.73 m2, stable, asymptomatic, not on dialysis. We performed a complete transthoracic echocardiography with 2D-STE and determined serum levels of PICP, P3NP and Gal-3 by ELISA. Patients in atrial fibrillation, with a permanent pacemaker or with a poor acoustic window were excluded.

Results

The mean age was 59.2±15.5 (median 61 years), 44% of the patients were males, 33% were diabetic, 11% had a history of myocardial infarction and 14% were smokers. The average volumetric ejection fraction (EF) was 54.4±9.8% (median 55%), with only 6.3% of the patients having an EF &lt;40%. The majority of the patients (86.6%) had at least grade I DD, with only 5.3% having a restrictive pattern (grade III DD). The mean GLS was −16.8% ± 0.1 (median −17%). The average serum levels of PICP, P3NP and Gal-3 were 440.2±139.6, 244.9±380.1 and 10.8±6.7, respectively. After regression analysis, GLS was correlated with PICP, P3NP and Gal-3 levels (p=0.005, r=0.88; p=0.001, r=0.75; and p=0.006, r=0.81 respectively). Additionally, GLS was inversely correlated with the severity of DD (p=0.0001, r=0.84). In multiple regression analysis of a model consisting of GLS, PICP, P3NP and Gal-3, the serum level of PICP counted for 34% of the variance of GLS (R2=0.559, p=0.002, F=32.39).

Conclusions

In conclusion, this study proves that although stable and asymptomatic, patients with ESRD have lower values of GLS, a high proportion of DD and higher values of PICP, P3NP and Gal-3, when compared with the general population, in spite of a normal EF. Our study is the first to demonstrate that these biomarkers correlated with GLS in patients with ESRD, suggesting that GLS could represent an important tool for estimating the amount of fibrosis and risk stratification in this population.

Funding Acknowledgement

Type of funding sources: None.

Ship Maneuvering Prediction based Pivot Point Estimation

In the last years, the size and the number of ships has grown remarkably. At the same time, the size of harbors and ports remain constantly. Asa result, the ship maneuvering in harbors has become more problematic and harder to execute. This is the reason that many sailors affirm that it is an art than a science to execute some maneuverings. Ship maneuvers represented a complex vessel motions influenced most of the time by external environmental conditions in the navigation area (i.e. ocean and tidal current conditions, water depth, wind and waves). Navigator`s knowledge and experiences overcome to control the ship speed, course and heading in some close encounter situations. For example, combinations of different environmental conditions (draft variations in a passage from fresh to sea water with other ships near the same navigation area), create not only additional navigation difficulties, but also could compromise and threatens the navigation.

[Vulvar cancer. The therapeutic aspects]

Even though it has a low frequency (4 - 5%) compared to genital cancers, it has certain biological features represented by the possibility of multicentric localisation what performs on the dystrophic lesions, the presence of the inguinal nodes, the sensibility of the irradiation of the cancer and nodes and the efficacity of the treatment of the treatment of the bleomicine which request many therapeutical problems. Between 1985-1994, in Colţea Surgery Clinic there were operated 13 vulvar carcinoma, in women between 45-69 years old, in stages II (6), III (4) and IV b (3). Primary lesion was on labia major (11), labia minor (1) and posterior fourchette (1). Preoperative radiotherapy was made in 9 patients. At 3 patients, valvar lesion represents the second cancer--in all cases were syndrome neoplasia, after cervix neoplasia (2) or ano-rectal neoplasia (1) which were operated. At histopathological exam all cancers were spinocellular epithelium keratosis in 10, non-keratosis in 2 or trabecular in 1. The surgical treatment was selective and consisted in total vulvectomy (9), vulvectomy with inguinal lymphadenectomy (3) and left colostomy (1) after ano-rectal invasions and intestinal obstruction. The postoperative mortality and complications were zero. Postoperative treatment consisted in radiotherapy in association with chemotherapy 93) or only chemotherapy (8). The survival rates at 3 years (2), 5 years (30, 7 years) (3) and 10 years (2), justify the complex treatment. In conclusion, vulvectomy represents the specific treatment associated with inguinal lymphadenectomy in case of lymph nodes metastasis. Postoperative radiotherapy and postoperative chemotherapy seem to increase the survival rate.

[Nongynecologic abdominal emergencies during pregnancy]

The paper reports on the authors' experience in the surgical emergency of a special category of patients: pregnant women with acute affections requiring surgery. The clinical aspects, sometimes deceptive, diagnosis difficulties and tactile and technical surgical attitudes are presented in detail.

Stress ulcers in intensive care (etiology, symptomatology and therapy)

The authors present a group of 48 patients with stress ulcers (36 men, 13 women) average age 56.2 years. The analysis of the cases allowed to establish, for the first time in medical literature, a correlation between the etiology, the symptomatology and the moment of onset of the haemorrhage, with important practical implications in the adoption of a treatment regime. These considerations permitted us to delineate four categories of stress ulcers: The first category included stress ulcers caused by a cerebral lesion and manifested through cerebral hypertension. The upper digestive haemorrhage occurred within 24-48 h after the aggression and required the correction of the cerebral hypertension and of the anaemia. The second category comprised stress ulcers brought about by a hypovolaemic shock through myocardial infarction, burns, frost-bite and multiple traumas. Haemorrhage in the upper digestive tract appeared within 3-6 days after the moment of aggression and required surgical control unless it was caused by myocardial infarction. The third category was represented by post-operative stress ulcers. These forms occurred usually late, between the eighth and the thirty-seventh day after the aggression, and were due to the super-imposition of the septicaemia on the post-aggressive systemic reaction. The chief aim of treatment here was the surgical control of infection. The fourth category encompassed the stress ulcers occurring after protracted coma, especially in patients with ventilatory assistance. In these conditions, the ulcers of the digestive tract and the consequent haemorrhage represented terminal elements of irreversible diseases, in which no treatment was effective.

[Subarachnoid anesthesia with pethidine]

The authors present their experience about spinal anesthesia with pethidine as the sole medication. 713 patients whose mean age was 56.5 years received 1 mg . kg-1 of pethidine in 50 p. 100 aqueous solution administered by subarachnoid route. Indications were surgical procedures involving upper and lower abdomen, perineum and lower limbs. The set up of anesthesia is quite similar to those obtained with local anesthetics. Sensitivity disappears during the first three minutes in the area below the puncture site and in the following two or three minutes areflexia and paralysis is noted. The duration of the motor and sensory block is 90 to 120 minutes. Recovery appears to be in a reverse order. Spinal anaesthesia with pethidine exhibit the following characteristics: --sensory and motor blockade with minimal adverse reactions giving good and very good results in more than 90 per cent of cases, when involving perineum and lower limbs; --the most frequent adverse effect is a syndrome including hypotension, bradycardia and hypoxemia, appearing 20 to 30 minutes after injection, reversal is easily obtained by administration of pressure drugs and artificial ventilation. Neither delayed respiratory depression nor neurologic damage were noted; --a long lasting post-operative analgesia. In conclusion, this work demonstrates that: --1 mg . kg-1 of pethidine administered by subdural route realize a complete spinal anesthesia including motor, sensory and sympathetic blockade allowing surgical procedures in good conditions of security; --increasing the dosage of pethidine over 1 mg . kg-1 is not wise in order to avoid the occurrence of adverse side effects such as hypotension, bradycardia and bradypnaea; --this technic is only indicated for surgery in perineum and lower limbs.

[Hyperlipoproteinemia, a factor of severity in acute pancreatitis]

The authors make a retrospective analysis of 95 cases of acute pancreatitis hospitalized between 1975 and 1979. In 3,8% of all the cases the acute pancreatitis was associated with hyperlipoproteinemia. The study of the 4 patients involved revealed the primary origin of hyperlipoproteinemia as a result of alimentary abuse in 3 of the cases. In a fourth case the increased serum lipoproteins were due to prolonged use of contraceptives. From the clinical viewpoint, pancreatitis associated with hyperlipoproteinemia was more severe, with signs of shock and collapse, respiratory failure, high serum nitrogen an hyperglycemia. The blood and the serum had a lactescent aspect, with a thick layer of chylomicrons. The serum and blood values for lipids were higher than 4000 mg%. The increase in the amount of lipids was especially due to high triglycerides values. From the anatomopathologic viewpoint the 4 patients presented as acute cases of cholecysto-pancreatitis with major and extensive haemorrhagic necrosis which involved almost the entire pancreas. The evolution of the four patients was difficult. Two of the patients recovered after a long hospitalization, and had definitive sequels - insulin-dependent diabetes. The other two patients died following septic complications (bronchopneumonia and visceral gangrene), and hypovolemia due to upper digestive haemorrhage.