Fingerprint recognition systems are vulnerable to artificial spoof fingerprint attacks, like molds made of silicone, gelatin or Play-Doh. "Liveness detection", which is to detect vitality information from the biometric signature itself, has been proposed to defeat these kinds of spoof attacks. The goal for the LivDet 2009 competition is to compare different methodologies for softwarebased fingerprint liveness detection with a common experimental protocol and large dataset of spoof and live images. This competition is open to all academic and industrial institutions which have a solution for software-based fingerprint vitality detection problem. Four submissions resulted in successful completion: Dermalog, ATVS, and two anonymous participants (one industrial and one academic). Each participant submitted an algorithm as a Win32 console application. The performance was evaluated for three datasets, from three different optical scanners, each with over 1500 images of "fake" and over 1500 images of "live" fingerprints. The best results were from the algorithm submitted by Dermalog with a performance of 2.7% FRR and 2.8% FAR for the Identix (L-1) dataset. The competition goal is to become a reference event for academic and industrial research in software-based fingerprint liveness detection and to raise the visibility of this important research area in order to decrease risk of fingerprint systems to spoof attacks.

Initially thought to be a primarily respiratory disease process, the hypercoagulable state associated with COVID-19 has been associated with myriad clinical sequelae. We report a case of stuttering ischemic priapism associated with COVID-19, and describe a management approach to achieve detumescence in patients undergoing ventilatory proning limiting penile access. Level of evidence: Not applicable for this single center case report.

The purpose of this study was to evaluate various methods of diagnosis of left atrial thrombi (LAT) in patients (pts) with mitral stenosis (MS). From 1980 to 1990, 581 pts with MS have undergone open mitral commissurotomy (n = 169) or valve replacement (n = 412). All pts had transthoracic 2D echocardiography (TTE), 101 transoesophageal echocardiography (TEE), 192 a left atrial angiography (A) (from a left ventricular injection if associated mitral regurgitation grade 3 (n = 154) or from an injection in the pulmonary artery (n = 38) and 229 a coronary angiography (CA). Tomodensitometry (TD), nuclear magnetic resonance (NMR) and 111 Indium platelet imaging (IPI) were performed in some cases, 2, 8 and 5 respectively. All these examinations were carried out in the month before surgery. LAT was found by the surgeon in 43 pts (7%). The site was left atrial appendage in 26 cases (60%) and left atrial cavity in 17 cases. Sensitivity (Se), specificity (Sp) of TTE/TEE/A/CA were the following: TTE, Se% 28, Sp% 99; TEE, Se% 83, Sp% 97; A, Se% 28, Sp% 99; CA, Se% 14, Sp% 100. Specificity was high with all methods but sensitivity was high only with TEE and poor with other methods because of difficulty in detecting thrombi of the left atrial appendage. Specificity and sensitivity of TD, NMR and IPI require more information. False-negative cases are possible with NMR (1 case) and IPI (1 case) in well established LAT. We conclude: TEE is the easiest way to detect LAT, particularly when located in the left atrial appendage. It should be carried out systematically before percutaneous mitral valvuloplasty or surgery.

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Level III retrospective comparative study.