Scleral Contact Lens Wear after Severe Ocular Infection
Rute Macedo-de-Araújo, José Manuel González-Méijome
Clinical & Experimental Optometry Research Lab (CEORLab). Center of Physics. University of Minho. Braga. Portugal
Beyond the common applications of scleral contact lenses (ScCLs) in the rehabilitation of corneal ectasia and severe dry eye (1,2), these devices can also play important roles in rehabilitating other conditions. One such condition is corneal scarring as a result of trauma or ocular infections by a variety of bacteria such as Pseudomonas aeruginosa (3), since they can cause aftereffects that can compromise visual function. This case report discusses an eye with a significant opacification and scarring of the cornea covering part of the pupil area. Despite the clinical presentation, the scleral lens device was able to rehabilitate vision to near normal values through the regularization of the irregular but clear corneal area over the remaining parts of the pupil.
A 38-year-old woman presented to the clinic concerned with her visual quality. She had been wearing daily disposable silicone hydrogel contact lenses for three years. Eleven months prior to this visit, she indicated that she’d had a Pseudomonas aeruginosa infection. She mentioned that on that day, she started feeling a burning sensation and pain in her left eye while on a train trip. When she arrived to her hometown in the afternoon, she immediately attended to an ophthalmologist, who patched her eye and applied non-specific medications. The next morning, the pain and secretion were so severe that she immediately went to the hospital and was straightway admitted. The ocular infection positive for Pseudomonas aeruginosa evolved to an endophtalmitis. Her prognosis was poor, with potential enucleation of the eye. Medical efforts and the patient’s dedication helped to get the infection under control, and the eye was saved from enucleation (see Figure 1).
Figure 1 OS: 11 months after the onset of the infection. An opacity over a significant part of pupil area is seen as well as corneal infiltrates.
When the patient left the hospital, her visual acuity OS was 0.1. This improved to 0.2 after 1 month, and a year after that her best-corrected visual acuity was reported to be 0.4 (with glasses). When she presented at our clinic, having been referred by the treating ophthalmologist for potential rehabilitation with contact lenses, she was using lubricant drops regularly for ocular dryness and irritation. She started wearing daily disposable soft CLs 8 months after the infection, but only 2 to 3 times per week and with poor visual acuity in her left eye.
At the time of her first visit to our clinic, the best spectacle-corrected visual acuity was 1.2 OD and 0.4-2 OS.
After inserting a scleral contact lens, her vision instantly improved to 0.7+2 OS. With over-refraction (OS -0.75 –0.25 x80º), her vision improved to 0.9-2. Her visual acuity could not be improved further, in part because of the corneal irregularities that remained after the infection and because of the loss of transparency over a significant part of the pupil area (Figure 1 and Figure 2).
After this first adaptation period, we ordered the Senso Mini Scleral Lens from Procornea (Eerbeek, Netherlands) with the following parameters:
Figure 2 Corneal topography OS. The cornea is highly irregular. It is important to note that the corneal topographies based on the projection principle of Placido rings have limitations to analyze very irregular corneas, namely those with loss of transparency, so this data needs to be analyzed carefully.
Figure 3 shows how the lens fit in various locations. Five minutes after lens insertion, the clearance behind the lens was reported to be 250µm; however, we know that ScCLs tend to “sink” into the conjunctiva after a while during lens wear, and this “sinking” is dependent on the subject and the lens. In this case, after 2h30 of lens wear, the clearance decreased by 100µm to 150µm. All quadrants were free of conjunctival blanching. The visual acuity was 0.8+1. The patient reported that comfort was excellent, and she subjectively rated the vision as ‘fantastic’. She felt very happy and confident with the lens and had no trouble with lens insertion and removal.
Figure 3 ScCL fit in all quadrants. A - overal lens fit; B – Nasal; C – Temporal; D – Superior; E – Inferior. No conjunctival blanching is seen in any quadrant.
1-month follow up: the patient presented for a contact lens check-up late in the afternoon, 9h after lens insertion. The comfort was optimal and the vision OS was still excellent (0.8+2). The clearance was around 120 µm over the more compromised area of the cornea.
3-month follow up: The patient wears the lens for 8-10 hours a day without any compromise. Her vision OS is still more than 0.8, and the lens exhibits the same behavior/ adaptation as in the initial visits. It is important to note that the symptoms of ocular dryness and irritation have decreased dramatically during ScCL wear.
As mentioned previously, ScCLs have demonstrated that they can be advantageous for visual rehabilitation of several ocular conditions. We can confirm that these lenses can have innumerous advantages to restore visual quality in cases of post-corneal infection even when there is some transparency loss, unless this is severe and covers the central pupil area. However, it is mandatory to monitor the amount of corneal clearance, especially over the affected area, to preserve corneal health. These lenses can offer excellent vision and comfort for these patients.
A possible complication of monocular wear of a ScCL is the potential prismatic effect that could be induced by decentration of the lens. Inferior decentration can cause some prism effects because of the fluid reservoir under the lens. Because for most patients ScCLs are fit bilaterally, this effect is rarely reported. In this case, a unilateral ScCL was fit, and, as in almost all cases, the lens was inferiorly decentered slightly. Nonetheless, the patient feels comfortable with her vision and has not reported any binocular vision-related complaints.
1. van der Worp E, Bornman D, Ferreira DL, et al. Modern scleral contact lenses: A review. Cont Lens Anterior Eye 2014;37:240-250
2. Visser, ES. Advanced contact lens fitting. Part five: The scleral contact lens: Clinical indications. Optician 1997;214:15-20
3. Pseudomonas aeruginosa. Alan R. Hauser and Egon A. Ozer. Nature Reviews (http://www.nature.com/nrmicro/posters/pseudomonas/posters.pdf)
Rute Araújo is currently a PhD student at the University of Minho (Braga, Portugal).
She graduated in Optometry and Vision Sciences (University of Minho) and in 2014 concluded a Masters degree in Advanced Optometry at the same University. During her master studies, she was the monitor of practical Contactology lessons integrated into the graduation in Optometry, was part of a research project funded by FCT with the theme “Light Distortion Analyzer: Developments and Applications,” and worked as an optometrist in optic shops.
Her research is focused on contact lenses (scleral lenses), ocular surface, optical quality of the human eye and light distortion.