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Grand Round : A unique case of corneal warpage secondary to continuous wear of a silicone hydrogel lens. Subjective M.C. is a Caucasian Female of 46 y.o. referred to the Clinique Universitaire de la Vision (U of Montreal) for topography. She is a computer worker. The referent had suspected corneal warpage secondary to continuous wear of her Focus Night and Day contact lenses and was looking for topographic mapping of her corneas to confirm his diagnosis. At the moment of her visit, the patient had ceased to wear her contact lenses for 3 weeks, complying with the recommendation of her optometrist. Her chief complaint was fluctuating and reduced vision at far and at night. This symptom appeared several months ago and was slowly deteriorating over time. Patient admitted to overwear her lenses, keeping them in eyes for more than a month at a time. She had been wearing this type of contact lenses since 2000. During this time, each pair of contact lenses lasted for 8 weeks in average, depending on the discomfort felt at the end of the wearing schedule. She has no glasses and relies only on her contact lenses to correct her ametropia. Her general health is good and she is taking anti-depressive medication (Effexor™) on a regular basis. Past ocular and general family history are not contributory. Objective Entering visual acuity without contact lenses are 20/200 OD, OS and OU. There is no strabismus and ocular motilities are smooth and complete in all gazes. Pupillary reflexes are normal without any defect. Ocular dominance is established with OS as dominant at far. Retinoscopy gives OD -2,75 -1,50 x 180 and OS -1,50 -1,25 x 165. Refractive findings are OD -2,50 -1,00 x 180 20/20 and -1,50 -1,25 x 175 20/20-1 OS with an addition of +1,00 for near vision (0,5 M at 40 cm). We were not able to compare these findings with previous results since no previous records were available at the clinic and her optometrist did not provide this information. Her contact lens correction (OD -2,25 OS -2,00, BC 8,4) is different but could represent a spherical equivalent approach to compensate for her ametropic condition with a slight under correction on the non dominant eye (OD) to favour near vision. Topographic maps (Medmont) are recorded and Sim K values are OD 44,1 x 44,6 @ 130 and OS 43,2 x 44,6 @ 85. E values are 0,61@127 and 0,82 @37 for OD and 0,66@85 and 0,89 @ 175 which represent abnormal findings considering the normal e value of the cornea (0,45). The left map highlights more a corneal warpage with a bulging area seen in the lower third of the cornea (pseudokeratoconus). The right eye shows a small corneal warpage affecting mainly the central area. Slit lamp biomicroscopy reveals normal lids without belpharitis. Both corneas were clear, without edema nor microcysts neither neovascularization. There was no visible fluorescein staining on the cornea neither on the conjunctiva. There was no hyperemia anywhere on the anterior segment. The only noticeable findings was a grade 1+ papillae on the upper tarsal area. Ocular fundus are observed without dilation and found within normal limits. Goldman tonometry measurement indicates 12 mm Hg o.u.. Assessment Corneal warpage secondary to overwear of continuous high-DK silicone hydrogel lenses. This warpage is considered moderate to low, probably already reduced compared to its original state considering that the patient was not wearing her contact lenses for 3 weeks prior to this evaluation. PLAN To restore the cornea to its original profile is the first goal of the treatment. Corneal warpage resolves habitually within 3 weeks but can take up to 6 months for severe cases. Complete restoration is considered when topographic maps and refraction gives the same results on 2 visits made at a different time. In this particular case, the warpage does surely not come from the lack of oxygenation provided to the cornea as it is the case habitually on contact lens patients wearing moderate to low-DK materials. The warpage found here is probably more related to the higher modulus of the lotrafilcon A material and a tight fit. Overwear of contact lenses could have play a role in this process as well. Considering the limitations of the patient without appropriate visual correction, and taking in account that to make a pair of glasses would not be appropriate because of the visual fluctuation that goes along the corneal restoration, it is decided to refit temporarily the patient in high-DK toric silicone hydrogel lens, to limit the wearing time and to strongly recommend to do not wear them overnight. Acuvue Oasys for Astigmatism are selected and the following parameters are prescribed: OD -2,50 -0,75 x 180; OS -1,50 -1,25 x 180 (BC 8,6/ 14,5). Lenses are centered, well positioned and without any rotation. There is no restriction on push-up and a 1,5 mm movement upon blinking. Visual acuity is 20/20-2 OD 20/20-1 OS and 20/20 o.u. at far. Near vision is comfortable at computer distance. A daily schedule of wear of no more than 10 hours is recommended and the patient is told to discard the lenses every 2 weeks. Hydrogen peroxide care regimen is prescribed. The patient is seen back a month later and the cornea show some improvement at this time. Patient complaints of bad vision at far. Refraction findings are OD – 3,25 -0,75 x 10 (20/20) OS -2,25 -0,75 x 180 (20/20). Cornea remained clear without staining nor with any adverse sign from contact lens wear. Topographic maps show more symmetrical patterns. New toric lenses are provided according to the new refraction. Patient was followed for 3 months. It took that time to get stabilized results for both topographic maps and refraction. The final findings are: OD -2,50 -0,50 x 10 (6/6) OS -2,25 -0,75 x 5 (20/20). Sim K values are OD 43,25 x 43,87 @ 100 and OS 42,5 x 43,25 @ 85. E values were more aligned with the standard findings. Since the patient get used to the 2 week-disposable modality, Acuvue Oasys lenses are prescribed, a spherical one on the right side (-2,50) and a toric one on the left side (-2,25 0,75 x 180). A pair of glasses is prescribed in order to allow her to remove her contact lenses periodically. Continuous or extended wear are strictly forbidden even if the modulus of the Oasys is lower than the N& D lenses one and, upon our knowledge, never been associated with corneal warpage. Discussion /Conclusion High DK contact lenses were introduced in the market mainly to provide more oxygen to the cornea. This case reports illustrates the fact that even with the highest oxygen permeability possible, some drawbacks can occur based on other parameters of these products. Especially with the first generation of Si-Hy lenses, practitioners have to pay attention to the fitting of the contact lenses, their behaviour on the ocular tissue and to consider other parameters than oxygen permeability to achieve the optimal fit. Modulus of the material can initiate mechanical adverse reaction such as GPC, SEAL and corneal warpage. Tighter lenses tend to compress the cornea and can contribute to mold the cornea. Ametropic shift after Si-Hy refit were attributed to material modulus more than to the higher oxygen level available for the corneal tissue. Patients with corneal warpage are most often asymptomatic but some could compliant of visual acuity fluctuation, discomfort and contact lens intolerance. Majority of cases will be resolved within 3 weeks but some patients can take up to 6 months to restore their corneal and refractive conditions. Finally, this case illustrates how useful topographic mapping is in the evaluation and the follow-up of contact lens patients. ---------------------