While other anti-epileptic drugs, gabapentin and topiramate, have limited effect in some patients, they have not been shown to be generally effective. Opiate derived analgesics are also largely ineffective, with only sporadic cases of beneficial effect. Epidemiology
PEPD is an extremely rare disorder with only 15 known affected families. There are some cases, however, of individuals originally diagnosed with epilepsy who are later determined to have PEPD. This suggests that rates of PEPD may be higher than currently believed. History
PEPD was originally described by Hayden and Grossman in 1959. At that time it was not given a specific name. A later report, by Dugan in 1972, labeled this disorder as familial rectal pain syndrome. This name was used for 33 years, until a consortium of patients and clinicians was formed in the hopes of discovering the genetic cause of PEPD. During this process a number of patients expressed dissatisfaction with the name and after considerable discussion between patients and clinicians the name paroxysmal extreme pain disorder was agreed upon in 2005. References


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Lenticonus  (/len·ti·co·nus/ (len″tĭ-ko´nus)) [lens + L. conus, cone] is a rare congenital anomaly of the eye characterized by a conical protrusion on the crystalline lens capsule and the underlying cortex. It can reach a diameter of 2 to 7 mm. The conus may occur anteriorly or posteriorly. If the bulging is spherical, instead of conical, the condition is referred to as lentiglobus. It produces a decrease in visual acuity and irregular refraction that cannot be corrected by either spectacle or contact lenses.Biomicroscopically lenticonus is characterized by a transparent, localized, sharply demarcated conical projection of the lens capsule and cortex, usually axial in localization. In an early stage, retro-illumination shows an oil dropletconfiguration. Using a narrow slit, the image of a conus is observed. In a more advanced stage associated subcapsular and cortical opacities appear. Retinoscopically the oil droplet produces a pathognomonic scissors movement of the light reflex. This phenomenon is due to the different refraction in the central and the peripheral area of the lens. Ultrasonography also can illustrate the existence of a lenticonus. A-scan ultrasonography may reveal an increased lens thickness and B- scanultrasonography may show herniated lenticular material, suggestive of a lenticonus. Amblyopia, cataract, strabismus and loss of central fixation may be observed in association with lenticonus posterior. Cataract, flecked retinopathy, posterior polymorphous dystrophy and corneal arcus juvenilis may be encountered in association with lenticonus anterior that occurs as a part of the Alport syndrome.There exist two distinct types of lenticonus based on the face of the lens affected.