Treatment strategies in primary vitreoretinal lymphoma: a 17-center European collaborative study.

IMPORTANCE: The best treatment option for primary vitreoretinal lymphoma (PVRL) without signs of central nervous system lymphoma (CNSL) involvement determined on magnetic resonance imaging or in cerebrospinal fluid is unknown. OBJECTIVE: To evaluate the outcomes of treatment regimens used for PVRL in the prevention of subsequent CNSL. DESIGN, SETTING, AND PARTICIPANTS: A retrospective cohort study was conducted at 17 referral ophthalmologic centers in Europe. We reviewed clinical, laboratory, and imaging data on 78 patients with PVRL who did not have CNSL on presentation between January 1, 1991, and December 31, 2012, with a focus on the incidence of CNS manifestations during the follow-up period. INTERVENTIONS: The term extensive treatment was used for various combinations of systemic and intrathecal chemotherapy, whole-brain radiotherapy, and peripheral blood stem cell transplantation. Therapy to prevent CNSL included ocular radiotherapy and/or ocular chemotherapy (group A, 31 patients), extensive systemic treatment (group B, 21 patients), and a combination of ocular and extensive treatment (group C, 23 patients); 3 patients did not receive treatment. A total of 40 patients received systemic chemotherapy. MAIN OUTCOMES AND MEASURES: Development of CNSL following the diagnosis of PVRL relative to the use or nonuse of systemic chemotherapy and other treatment regimens. RESULTS: Overall, CNSL developed in 28 of 78 patients (36%) at a median follow-up of 49 months. Specifically, CNSL developed in 10 of 31 (32%) in group A, 9 of 21 (43%) in group B, and 9 of 23 (39%) in group C. The 5-year cumulative survival rate was lower in patients with CNSL (35% [95% CI, 50% to 86%]) than in patients without CNSL (68% [95% CI, 19% to 51%]; P = .003) and was similar among all treatment groups (P = .10). Adverse systemic effects occurred in 9 of 40 (23%) patients receiving systemic chemotherapy; the most common of these effects was acute renal failure. CONCLUSIONS AND RELEVANCE: In the present series of patients with isolated PVRL, the use of systemic chemotherapy was not proven to prevent CNSL and was associated with more severe adverse effects compared with local treatment

HIGH-SPEED PHOTOGRAPHIC EVALUATION OF ENDOSCOPIC LITHOTRIPSY DEVICES

Shock-wave generation and bubble formation occurring during endoscopic lithotripsy were studied using high-speed photography for various devices: a pulsed-dye laser, a Q-switched Nd:YAG laser and an electrohydraulic (EHL) apparatus. The three devices investigated generated gas bubbles that rapidly expanded and decayed. The maximal size of these bubbles was 5-8 mm for the pulsed-dye laser, 6 mm for the Q-switched Nd: YAG laser and up to 14 mm for the EHL device. The bubble size appeared to be governed mainly by the energy per pulse delivered by the lithotripsy device. The shock-wave pattern depended strongly on the type of device used; the 25-ns Q-switched Nd:YAG laser pulse generated a single pressure step, whereas the 1.5-mu-s pulsed-dye laser produced a train of shock front

Towing with sailboat robots

International audienceMoving huge objects floating at the surface of the ocean (such as containersor icebergs) with boats requires many human operators and a lot of energy.This is mainly due to the fact that when humans operate such equipment, time iscostly. Now, when we have time (as when robots operate, for instance), it is possibleto move arbitrarily large objects, for over long distances, with a limited quantity ofenergy. This is a consequence of the fact that in the water, the friction forces areproportional to the square of the speed (i.e., when we go slowly, we have almostno friction). This paper proposes the use of a sailboat robot to tow large objects. Itshows which control law could be used is order to (i) avoid loops inside the towingcable, (ii) avoid collisions between the robot and the towed object, and (iii) movethe object toward the desired direction. The control law is validated on a simulationwhere the object to be towed has to follow a trajectory corresponding to a largecircle

Reproducibility of electrocardiographic findings in patients with suspected reflex neurally-mediated syncope

The reproducibility of electrocardiographic (ECG) recordings in syncopal recurrences and the diagnostic role of nonsyncopal arrhythmias are not well known. The objective of this study was to analyse the reproducibility of the ECG findings recorded with implantable loop recorders in 41 patients with suspected neurally-mediated syncope who were included in the International Study on Syncope of Uncertain Origin-2 study and that had > or =2 events recorded by implantable loop recorders. In these patients, the electrocardiogram obtained with the first documented syncope (index syncope) was compared with other recorded events. Twenty-two patients had > or =2 syncopes, and their electrocardiograms were reproducible in 21 (95%): 15 with sinus rhythm, 5 with asystole, and 1 with ventricular tachycardia; 1 had asystole at first syncope and sinus rhythm at recurrent syncope. In 32 patients with nonsyncopal episodes, an arrhythmia was documented in 9, and all of them had the same arrhythmia during the index syncope (100% reproducibility); conversely, when sinus rhythm was documented (23 patients) during nonsyncopal episodes, an arrhythmia was still documented in 6 during the index syncope (70% reproducibility; p = 0.0004). In conclusion, the ECG findings during the first syncope are highly reproducible in subsequent syncopes. The presence of an arrhythmia during nonsyncopal episodes is also highly predictive of the mechanism of syncope, but the presence of sinus rhythm does not rule out the possibility of arrhythmia during syncope. Therefore the finding of an arrhythmia during a nonsyncopal episode allows the etiologic diagnosis of syncope, and eventually to anticipate treatment, without waiting for syncope