Cause or aeitology as we physicians like to impress with our knowledge of Latin, of keratoconus is under heavy research right now.History of Keratoconus spans two centuries.
It appears so far that there may be more than one cause or that it is multifactorial. Either one or many factors acting in concert can lead tokeartoconus.
1.Genetic: is keratoconus hereditary. This is what research on keratoconus has produced so far There is positive family history in 6-8 percent of the patients. The various different research studies have shown that the prevelance in first degree relatives is 15-67 times higher then in general population. Even unaffected first degree relatives have higher incidence of abnormal corneal topography. Linkage mapping and mutation analysis haveindicated the location for autsomal dominant inherited Keratocones.
2. Inflammatory:though keratoconus has traditionally been defined as non inflammatory disease recent insight into the causes of keratoconus have shown that inflammation may be involved. The levels of immunoglobin Ig G , Ig M and Ig E are elevated. Other mediators of inflammation like cIL-6, TNF-α, and MMP-9 are higher in keratoconus patients as compared to patients without keratoconus. MMP-9 may be involved in corneal inflammation.The cornea is made of collagen fibers, intact collagen compromises 70% by weight. In keratoconus , there is damage to the extracellular matrix associated with a decreas in type 1 and 4 collagen. Collagen degradation products called telopeptides are 3.5 times higher in keratoconus patients. A“cascade hypothesis of keratoconus” has been proposed. Enzymes cause a change in corneal proteins predisposing to oxidative damage, leading to cell death, altered signaling pathways, increased enzyme activities and fibrosis. There is evidence that the inhibitors of destructive enzymes – alpha one (α1 proteinase inhibitor, alpha two (α2) macroglobulin, and tissue inhibitor metalloproteinase one (TIMP-1 are decreased in keratoconus corneas; the latter can prevent cell death.
3. Eye rubbing it may cause micro trauma , also rubbing may be a response to the inflammatory factors.
4: contact lenses causing microtrauma
5: atopy or allergies
Knowledge about the pathology of keratoconus is instrumental in devising treatment of keratoconus.
Suspect keratoconus . When there are no obvious signs displayed for keratoconus, but there is high suspicion of subclinical keratoconus, the eye is labeled as suspect keratoconus. Some examples are the supposedly normal fellow eye of a patient with keratoconus. If both parents’ and/or siblings have keratoconus and the person has thin corneas or steep corneas he may be suspected to develop keratoconus later in life.
While research into causes and newer tretments for keratoconus is progressing it is important that all relatives of keratoconus patients get their eyes screened by a keratoconus surgeon.Ventura, oxnard, santa barbara residents may have thier consult in our Westlake Village office next to thousand oaks post office. Patients from Beverly hills, Rancho Cucamonga, Culver city and Santa Monica can book their keratoconus consults in our Beverly Hills office located near Cedars Sinai Hospital.