Couching is the earliest documented form of cataract surgery. As a cataract is a clouding in the lens of the eye, couching is a technique whereby the lens is dislodged, thus removing the opacity. Although couching is nowadays routinely practiced only in remote areas, it was a precursor to modern cataract surgery and

pars plana vitrectomy Vitrectomy is a surgery to remove some or all of the vitreous humor from the eye. Anterior vitrectomy entails removing small portions of the vitreous humor from the front structures of the eye—often because these are tangled in an intraocular ...

History

Cataract surgery by “couching” (lens depression) is one of the oldest surgical procedures. The technique involves using a sharp instrument to push the cloudy lens to the bottom of the eye. Perhaps this procedure is that which is mentioned in the articles of the

Code of Hammurabi The Code of Hammurabi is a Babylonian legal text composed 1755–1750 BC. It is the longest, best-organised, and best-preserved legal text from the ancient Near East. It is written in the Old Babylonian dialect of Akkadian, purportedly by Hamm ...

(ca. 1792–1750 BC) though it is a mere speculation.

Sushruta Sushruta, or ''Suśruta'' (Sanskrit: सुश्रुत, IAST: , ) was an ancient Indian physician. The ''Sushruta Samhita'' (''Sushruta's Compendium''), a treatise ascribed to him, is one of the most important surviving ancient treatises on ...

, an ancient Indian surgeon, described the procedure in “Sushruta Samhita, Uttar Tantra”, an Indian medical treatise (800 BC) (Duke-Elder, 1969; Chan, 2010). From then on the procedure was widespread throughout the world. Evidence shows that couching was widely practiced in China, Europe and Africa. After the 19th century AD, with the development of modern cataract surgery (Intra ocular extraction of lens (1748)), couching fell out of fashion, though it is still used in parts of Asia and Africa.

Modern use

Couching continues to be popular in some developing countries where modern surgery may be difficult to access or where the population may prefer to rely on traditional treatments. It is commonly practiced in

Sub-Saharan Africa Sub-Saharan Africa is, geographically, the area and regions of the continent of Africa that lies south of the Sahara. These include West Africa, East Africa, Central Africa, and Southern Africa. Geopolitically, in addition to the List of sov ...

. In Mali it remains more popular than modern cataract surgery, despite the fact that the cost of both methods is similar, but with much poorer outcome with couching. In Burkina Faso, a majority of patients were unaware of the causes of cataracts and believed it to be due to

fate Destiny, sometimes referred to as fate (from Latin ''fatum'' "decree, prediction, destiny, fate"), is a predetermined course of events. It may be conceived as a predetermined future, whether in general or of an individual. Fate Although often ...

. It is not performed by ophthalmologists, but rather by local healers or " witch doctors".

Technique

A sharp instrument, such as a thorn or needle, is used to pierce the eye either at the edge of the cornea or the

sclera The sclera, also known as the white of the eye or, in older literature, as the tunica albuginea oculi, is the opaque, fibrous, protective, outer layer of the human eye containing mainly collagen and some crucial elastic fiber. In humans, and som ...

, near the

limbus Limbus (Lat. "edge, boundary") may refer to: * Corneal limbus, the border of the cornea and the sclera (the white of the eye) * Limbus of fossa ovalis, in the heart * Limbus 3 and Limbus 4, two line-ups of a German avant-garde musical group * Li ...

. The opaque lens is pushed downwards, allowing light to enter the eye. Once the patients sees shapes or movement, the procedure is stopped. The patient is left without a lens ( aphakic), therefore requiring a powerful positive prescription lens to compensate.

Results

Couching is a largely unsuccessful technique with abysmal outcomes. A minority of patients may regain low or moderate visual acuity, but over 70% are left clinically blind with worse than 20/400 vision. A Nigerian study showed other complications include secondary glaucoma,

hyphaema Hyphema is a condition that occurs when blood enters the front (anterior) chamber of the eye between the iris and the cornea. People usually first notice a loss of vision or decrease in vision. The eye may also appear to have a reddish tinge, o ...

, and optic atrophy. Couching does not compare favourably to modern cataract surgery.

References

{{DEFAULTSORT:Couching (Ophthalmology) Eye surgery