Leber congenital amaurosis (LCA) is a rare inherited eye disease that appears at birth or in the first few months of life.It affects about 1 in 40,000 newborns. LCA was first described by Theodor Leber in the 19th century. It should not be confused with Lebers hereditary optic neuropathy, which is a different disease also described by Theodor Leber. One form of LCA was successfully treated with gene therapy in 2008. Signs and symptoms
The term congenital refers to a condition present from birth (not acquired) and amaurosis refers to a loss of vision not associated with a lesion. However, beyond these general descriptions, the presentation of LCA can vary, because it is associated with multiple genes.LCA is typically characterized by nystagmus, sluggish or absent pupillary responses, and severe vision loss or blindness. Genetics
It is usually autosomal recessive; however, importantly for family planning, it is sometimes autosomal dominant. It is a disorder thought to be caused by abnormal development of photoreceptor cells.OMIM currently recognizes 18 types of LCA. The gene CEP290 has been associated with Joubert syndrome, as well as type 10 LCA. Diagnosis
Genetic tests and related research are currently being performed at Centogene AG in Rostock, Germany; John and Marcia Carver Nonprofit Genetic Testing Laboratory in Iowa City, IA; GENESIS Center for Medical Genetics in Poznan, Poland; Miraca Genetics Laboratories in Houston, TX; Asper Biogene in Tartu, Estonia; CGC Genetics in Porto, Portugal; CEN4GEN Institute for Genomics and Molecular Diagnostics in Edmonton, Canada; and Reference Laboratory Genetics - Barcelona, Spain.
A metatarsophalangeal joint sprain is an injury to the connective tissue between the foot and a toe (at a metatarsophalangeal joint, one of the joints in the ball of the foot). When the big toe is involved, it is known as "turf toe". Causes
Turf toe is named from the injury being associated with playing sports on rigid surfaces such as artificial turf and is a fairly common injury among professional American football players. Often, the injury occurs when someone or something falls on the back of the calf while that legs knee and tips of the toes are touching the ground. The toe is hyperextended and thus the joint is injured. Additionally, athletic shoes with very flexible soles combined with cleats that "grab" the turf will cause overextension of the big toe. This can occur on the lesser toes as well. It has also been observed in sports beyond American football, including soccer, baseball, basketball, rugby, volleyball, and tae kwon do. This is a primary reason why many athletes prefer natural grass to turf, because it is softer. Treatment
The injury can be debilitating for athletes of many sports who need to accelerate, quickly change direction, or jump. Use of the toes is not possible during the healing process. Since the toes are necessary for proper push-off when accelerating, those sorts of athletic activities should be almost completely curtailed.