Translational approaches to obsessive-compulsive disorder: from animal models to clinical treatment.

Obsessive-compulsive disorder (OCD) is characterized by obsessions (intrusive thoughts) and compulsions (repetitive ritualistic behaviours) leading to functional impairment. Accumulating evidence links these conditions with underlying dysregulation of fronto-striatal circuitry and monoamine systems. These abnormalities represent key targets for existing and novel treatment interventions. However, the brain bases of these conditions and treatment mechanisms are still not fully elucidated. Animal models simulating the behavioural and clinical manifestations of the disorder show great potential for augmenting our understanding of the pathophysiology and treatment of OCD. This paper provides an overview of what is known about OCD from several perspectives. We begin by describing the clinical features of OCD and the criteria used to assess the validity of animal models of symptomatology; namely, face validity (phenomenological similarity between inducing conditions and specific symptoms of the human phenomenon), predictive validity (similarity in response to treatment) and construct validity (similarity in underlying physiological or psychological mechanisms). We then survey animal models of OC spectrum conditions within this framework, focusing on (i) ethological models; (ii) genetic and pharmacological models; and (iii) neurobehavioural models. We also discuss their advantages and shortcomings in relation to their capacity to identify potentially efficacious new compounds. It is of interest that there has been rather little evidence of 'false alarms' for therapeutic drug effects in OCD models which actually fail in the clinic. While it is more difficult to model obsessive cognition than compulsive behaviour in experimental animals, it is feasible to infer cognitive inflexibility in certain animal paradigms. Finally, key future neurobiological and treatment research areas are highlighted.

Bilateral idiopathic macular pucker: a case report.

BACKGROUND: Idiopathic epiretinal membrane or macular pucker is a common disorder which typically affects older individuals. Contraction of epiretinal tissue causes changes to occur in the underlying retina stimulating the appearance of a macular hole. This paper presents a case of bilateral macular pucker with accompanying pseudohole. The diagnosis, pathophysiology and management are discussed. METHODS: A 68-year-old male was examined for decreased vision in both eyes. Relevant ophthalmoscopic findings included macular changes compatible with surface wrinkling maculopathy. RESULTS: The patient was diagnosed with bilateral epiretinal membranes with accompanying pseudoholes. The diagnosis was confirmed by fluorescein angiography. Since the patient's vision loss was minimal, the need for surgery was precluded. The patient was to be monitored routinely. CONCLUSIONS: Macular pucker, the most common of acquired macular disorders, has become an important clinical entity. Recognizing distinguishing features, especially in cases associated with pseudohole, will allow more precise diagnostic and prognostic patient counseling. Regular follow-up examinations of patients with mild visual loss become important, because they permit optimal time for surgical intervention.