Preclinical Safety and Efficacy Assessments for Novel Femtosecond Lasers in Corneal Refractive Surgery.

Preclinical safety requirements and test methods have been standardized over time to guide medical device developers in the path needed to manufacture safe devices and achieve regulatory approval. Today, femtosecond lasers are commonly used in cataract and refractive surgeries. Currently, an industry standard to guide developers in preclinical testing of ophthalmic lasers does not exist.

Preclinical Safety Evaluation of Ophthalmic Viscosurgical Devices in Rabbits and a Novel Mini-Pig Model.

Introduction: To establish the preclinical safety and equivalency of ophthalmic viscosurgical devices (OVDs) comprised of bacterially sourced sodium hyaluronate (HA) to animal sourced HA using pyrogenicity and aqueous exchange models in rabbits and a novel mini-pig model to evaluate corneal endothelial cell protection in vivo.

Methods: HEALON OVD and HEALON5 OVD containing animal-derived HA and HEALON PRO OVD and HEALON5 PRO OVD containing bacterial-derived HA were used. Two rabbit aqueous exchange studies were conducted where aqueous humor was exchanged with OVDs in six animals each to observe potential ocular inflammation, intraocular pressure (IOP) response, corneal health and pachymetry until 7 days post procedure, as well as overall assessment of the OVDs.

Systematic review of co-occurring OCD and TD: Evidence for a tic-related OCD subtype?

Objective: The aim of this review is to summarize the current knowledge of associated features of co-occurring obsessive-compulsive disorder (OCD) and tic disorders (TD) and to critically evaluate hypotheses regarding the nature of their comorbidity.

Method: We conducted a systematic review following PRISMA guidelines. To this aim, the PubMed, PsychInfo and ISI Web of Knowledge databases were searched up to August 30, 2018.

Volitional saccade performance in a large sample of patients with obsessive-compulsive disorder and unaffected first-degree relatives.

Recent evidence indicates that patients with obsessive-compulsive disorder (OCD) as well as their unaffected first-degree relatives show deficits in the volitional control of saccades, suggesting that volitional saccade performance may constitute an endophenotype of OCD. Here, we aimed to replicate and extend these findings in a large, independent sample. One hundred and fifteen patients with OCD, 103 healthy comparison subjects without a family history of OCD, and 31 unaffected first-degree relatives of OCD patients were examined using structured clinical interviews and performed a volitional saccade task as well as a prosaccade task.

Response selection in prosaccades, antisaccades, and other volitional saccades.

Saccades made to the opposite side of a visual stimulus (antisaccades) and to central cues (simple volitional saccades) both require active response selection but whether the mechanisms of response selection differ between these tasks is unclear. Response selection can be assessed by increasing the number of response alternatives: this leads to increased reaction times when response selection is more demanding. We compared the reaction times of prosaccades, antisaccades, saccades cued by a central arrow, and saccades cued by a central number, in blocks of either two or six possible responses.

Impaired volitional saccade control: first evidence for a new candidate endophenotype in obsessive-compulsive disorder.

Recent research suggests that patients with obsessive-compulsive disorder (OCD) have deficits in the volitional control of saccades. Specific evidence comes from increased latencies of saccadic eye movements when they were volitionally executed but not when they were visually guided. The present study sought to test whether this deviance represents a cognitive endophenotype.

Approach and avoidance learning in obsessive-compulsive disorder.

Background: Current neurobiological models of obsessive-compulsive disorder (OCD) propose a dysfunction of cortico-striato-thalamo-cortical circuits that leads to enhanced activity in frontal and striatal brain regions. In accordance with that, OCD patients show alterations in learning and flexible adaptation to changing task requirements. The purpose of this study was to examine feedback-based learning and to investigate whether learning from positive and negative feedback is differentially altered in OCD.

Evidence for a deficit in volitional action generation in patients with obsessive-compulsive disorder.

Obsessive-compulsive disorder (OCD) patients show deficits in tasks of executive functioning like the antisaccade (AS) task. These deficits suggest problems in response inhibition or volitional saccade generation. Thirty patients (15 nonmedicated) and 30 healthy subjects performed antisaccades and simple volitional saccades (SVS), that is, centrally cued saccades.