Extrapyramidal symptoms (EPS) are symptoms that are archetypically associated with the extrapyramidal system of the brains cerebral cortex. When such symptoms are caused by medications or other drugs, they are also known as extrapyramidal side effects (EPSE). The symptoms can be acute (short-term) or chronic (long-term). They include movement dysfunction such as dystonia (continuous spasms and muscle contractions), akathisia (may manifest as motor restlessness), parkinsonism characteristic symptoms such as rigidity, bradykinesia (slowness of movement), tremor, and tardive dyskinesia (irregular, jerky movements). Extrapyramidal symptoms are a reason why subjects drop out of clinical trials of antipsychotics; of the 213 (14.6%) subjects that dropped out of one of the largest clinical trials of antipsychotics (the CATIE trial (Clinical Antipsychotic Trials for Intervention Effectiveness), which included 1460 randomized subjects), 58 (27.2%) of those discontinuations were due to EPS. Causes
Medications
Extrapyramidal symptoms are most commonly caused by typical antipsychotic drugs that antagonize dopamine D2 receptors. The most common typical antipsychotics associated with EPS are haloperidol and fluphenazine. Atypical antipsychotics have lower D2 receptor affinity or higher serotonin 5-HT2A receptor affinity which lead to lower rates of EPS.Other anti-dopaminergic drugs, like the antiemetic metoclopramide, can also result in extrapyramidal side effects. Short and long-term use of antidepressants such as selective serotonin reuptake inhibitors (SSRI), serotonin-norepinephrine reuptake inhibitors (SNRI), and norepinephrine-dopamine reuptake inhibitors (NDRI) have also resulted in EPS. Specifically, duloxetine, sertraline, escitalopram, fluoxetine, and bupropion have been linked to the induction of EPS. Non-medication-related
Other causes of extrapyramidal symptoms can include brain damage and meningitis.
Corneal ectatic disorders or corneal ectasia are a group of uncommon, noninflammatory, eye disorders characterised by bilateral thinning of the central, paracentral, or peripheral cornea. Types
Keratoconus, a progressive, noninflammatory, bilateral, asymmetric disease, characterized by paraxial stromal thinning and weakening that leads to corneal surface distortion. Keratoglobus, a rare noninflammatory corneal thinning disorder, characterised by generalised thinning and globular protrusion of the cornea. Pellucid marginal degeneration, a bilateral, noninflammatory disorder, characterized by a peripheral band of thinning of the inferior cornea. Posterior keratoconus, a rare condition, usually congenital, which causes a nonprogressive thinning of the inner surface of the cornea, while the curvature of the anterior surface remains normal. Usually only a single eye is affected. Post-LASIK ectasia, a complication of LASIK eye surgery. Terriens marginal degeneration, a painless, noninflammatory, unilateral or asymmetrically bilateral, slowly progressive thinning of the peripheral corneal stroma. Diagnosis
Usually diagnosed clinically by several clinical tests. Although some investigations might needed for confirming the diagnosis and to differentiate different types of corneal ectatic diseases. Corneal topography
Corneal tomography

Treatment
Treatment options include contact lenses and intrastromal corneal ring segments for correcting refractive errors caused by irregular corneal surface, corneal collagen cross-linking to strengthen a weak and ectatic cornea, or corneal transplant for advanced cases. References
External links
International Journal of Keratoconus and Ectatic Corneal Diseases