The ACIOL is also vaulted and must be placed in the correct orientation. An incorrectly sized ACIOL can result in UGH syndrome via tilting and haptic chafing on anterior segment structures.
#Timing synonym plus#
The general size for ACIOL placement is horizontal corneal white-to-white distance plus 1mm. If an ACIOL is required then the correct size of the lens should be chosen. If there is inadequate capsular support then a 3 piece sulcus lens can be fixated via scleral fixation. It is important to place the 3 piece lens in the correct orientation within the sulcus as the lens is vaulted. Additionally, reverse optic capture of the lens can be attempted by placing the edges under the anterior capsulorhexis. If there is enough support a 3-piece lens should be placed within the sulcus. A 1 piece lens should not be placed in the sulcus. If this is not possible due to intraoperative complications, then there are other lens types and techniques that should be undertaken to prevent uveal disruption from the intraocular lens. During routine cataract surgery, a 1 piece lens and haptics should be placed within the lens capsule. Prevention of UGH syndrome is the main reason for the decreased incidence of the disease. Electron microscopy of explanted IOLs often reveals melanosomes on the IOL, likely from damaged iris pigment epithelial cells. Additionally, contact with angle structures by the IOL can cause destruction of outflow structures and increased IOP. With pigment, red blood cells, and white blood cells in the anterior chamber, the trabecular meshwork can become blocked causing an increase in intraocular pressure. The release of red blood cells causes a microhyphema or hyphema. This chafing can lead to a breakdown of the blood-aqueous barrier and subsequent release of pigment, red blood cells, protein, and white blood cells into the anterior chamber. General PathologyĪnterior chamber bleeding can be due to by peripupillary contact of iris with lens optic/haptics, and warpage of footplates or edge imperfections leading to mechanical irritation and erosion of uveal structures including the iridocorneal angle, iris, and ciliary body. Single-piece acrylic IOLs placed within the sulcus tend to have a high UGH complication rate. Evidence of UGH occurring within 6 months of intraocular lens implant is consistently higher in anterior chamber lenses than in iris plane lenses than in posterior chamber lenses. While most commonly in elderly adults, it has been reported in the pediatric population. This entity can occur in any age group with an intraocular lens. This can also occur from cosmetic iris implants.
The disease is the result of mechanical irritation of anterior segment structures from an intraocular lens. As these factors changed, studies showed that the incidence of UGH syndrome decreased from a mean of 2.2 to 3% to 0.4 to 1.2% depending on the IOL type over a one-year period. The incidence of UGH has sharply declined due to refinement of lens design, IOL fabrication, IOL material, surgical techniques, and increased use of posterior chamber IOLs.
He noticed that certain styles of anterior chamber intraocular lenses had warped footplates leading to a rocking motion of the lens and mechanical irritation of adjacent anterior chamber angle structures. The term UGH Syndrome was first coined by Ellingson in 1978. Surgical intervention is often required as definitive treatment. It is characterized by chronic inflammation, cystoid macular edema (CME), secondary iris neovascularization, recurrent hyphemas, and glaucomatous optic neuropathy leading to a loss of vision. It is most commonly caused by chafing from anterior chamber intraocular lenses but can occur from any type of pseudophakic lens. Uveitis-Glaucoma-Hyphema (UGH) Syndrome or Ellingson syndrome is a complication of intraocular chafing from intraocular lens (IOL) implants leading to a spectrum of iris transillumination defects and pigmentary dispersion to microhyphemas and hyphemas with elevated intraocular pressure (IOP). Lens-induced iridocyclitis H20.21 (right eye), H20.22 (left eye), H20.23 (bilateral).Mechanical complication of IOL implant T85.22X (displaced) or T85.23X (other).Glaucoma secondary to other eye disorders H40.51X (right eye), H40.52X (left eye) H40.53X (bilateral).
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