Post LASIK Epithelial Ingrowth
By Dr.Hoda Gabroun
epith ingrowth after lasik .whats the treatment?
By Dr.Mohammad Ibrahim Salem Elevate the flap and scrap with a spatula then suture to the bed,Or You can use YAG laser without flap lifting but i think it is suitable for small areas of epith ingrowth.
By Dr.Mazen Sinjab In spite of the guidelines of treatment based on the grade, we have to be as conservative as possible. Re-lifting the flap to scrap the epithelium carries the risk of harvesting the edge of the flap at Bowman’s layer, the thing that will create a new port for the epithelium apart from the high recurrence rate of the same previous port. Therefore, Holladay suggested that we have to cut the hand of the epithelium, and let the islands of epithelium under the flap to die by itself, because the epithelium under the flap cannot survive without the feeding epithelium stream coming through the port. He suggested to inspect the edge of the flap by the slitlamp under high magnification to find the port and then we have to cut the hand of the epithelium by alcohol or by Yag laser, and then suture that area without lifting the flap. After that, the epithelial islands will resolve spontaneously.
Post LASIK Epithelial Ingrowth
Ingrowth of epithelium into the corneal flap interface is a relatively uncommon complication of LASIK. The incidence of visually significant epithelial ingrowth is about 1% in primary cases and 2% on enhancement cases in microkeratome-assisted flap creation.The incidence may be less with femtosecond-assisted flap creation.Ingrowth of these cells into the corneal stromal interface is usually asymptomatic, however, these cells may lead to decreased vision due to irregular corneal astigmatism, direct intrusion of cells into the visual axis, or lead to melting of the overlying flap. Treatment is generally needed in instances where there is decreased vision or threat for a flap melt.
Grade 1 ingrowth may be observed. Grades 2 and 3 require treatment. Treatment involves removing the invading epithelial cells from the interface and achieving closure of the flap edge to prevent recurrent invasion of epithelium into the flap stromal interface space.
Topical antibiotics and steroids are given postoperatively as per routine after LASIK surgery. A bandage contact lens may be placed to improve comfort. Glasses and contact lenses may be used to improve vision at least until the patient is treated surgically.
Medical follow up
Patients diagnosed with grade 1 epithelial ingrowth should be seen weekly for one month with accurate documentation and measurements to determine stability or progression. If stable, resume routine follow up care. If progression is noted, treatment should be considered as per the Probst/Machat grading criteria.
Surgery should be considered as per the Probst/Machat grading criteria.
The general treatment for removing epithelial ingrowth is lifting the flap and scraping the epithelial cells from the stromal bed and undersurface of the flap, typically followed by placed of a bandage contact lens. The recurrence rate of lifting and scraping the cells alone has been reported to be as high as 44%. Adjuvant treatments such as ethanol, mitomycin, phototherapeutinc keratectomy (PTK) have been described for recurrent epithelial ingrowth, however, these may cause adverse effects.Suturing the flap after removal of the epithelial cells to create a tight apposition between the flap and the stromal bed has been shown to reduce the recurrence rate without the adverse effects of the listed adjunctive treatments.Adjunctive gluing of the flap after epithelial debribement in recurrent ingrowth cases to improve flap adhesion to the stromal bed has also been reported to have favorable outcomes. Additionally, Nd:YAG laser is another method used to destroy epithelial cells. This option may be especially useful when cells are encroaching the visual axis.
There are also reports of using amniotic membrane as an adjuvant therapy for the prevention of epithelial in-growth in patients who require placement of sutures in the visual axis. The membrane has intrinsic elasticity and if sutured tightly to the episclera, it can serve as a gentle pressure patch over the flap.
Surgical follow up
Patients undergoing a debridement procedure to remove the invading epithelium should be monitored for recurrence. These patients are generally seen the day following the procedure, one week, one month, and 3 months after the procedure if the exam findings show no evidence for recurrence. The contact lens is generally removed at the one-week visit.
Epithelial ingrowth that has been persistent in the flap interface for weeks to months may lead to flap melting within 2 weeks. Flap melt usually begins at the flap edge overlying the area of epithelial invading cells. Flap melting has been described as secondary to collagenase release from hypoxic epithelial cells underneath the flap. The patient may be asymptomatic, however, flap melts can lead to a distortion of the corneal surface with possible astigmatic changes and secondary tear film disruption leading to dry eye problems.
Once flap melt has occurred, treatment may not be necessary as the trapped epithelial cells have reached the surface. However, enhancements by relifting the flap after a flap melt may be quite difficult as the flap will be very adherent at the site of the melt.
Haze and scarring from inactive or treated epithelial ingrowth may be associated with glare, haloes, ghosting, and decreased vision.
Most epithelial ingrowth can be categorized as grade 1 and is visually insignificant. The visual results and overall outcome of treatment of visually significant ingrowth is generally excellent when the ingrowth is diagnosed early and treated adequately with preservation of flap integrity.