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Two unusual and difficultsoft lens cases
Two unusual and difficult soft lens cases ANDREW GASSON The following case histories represent a chronological discussion of two particularly difficult and time consuming patients who have both been wearing soft lenses since 1973. During this time, because of their wide range of clinical problems, they have worn, or tried to wear, most types of soft lens currently available. They therefore provide an interesting retrospect of a constantly changing approach to soft lens fitting.
three weeks when the left lens had to be replaced because of a rust spot. Everything then went well until April 1974. By this time the left lens had become excessively loose and unstable on the cornea. It was badly discoloured and the surface was cracked and crazed, requiring replacement. In May 1974, that is just one month later, the patient complained of irritation of the left eye. It was very injected, with peripheral arcuate staining. Lenses were left out for three days, and he was instructed to use the newly introduced enzymatic protein tablets on a regular basis. This he apparently failed to do, and in August 1974, Mr G A was again seen with sudden discomfort in the left eye. Both lenses were badly discoloured, and follicles were seen on the palpebral conjunctiva of the left upper lid. No staining was evident on this occasion. By December 1974, both of the Bausch & Lomb lenses were worn out, and the patient was refitted with 15.00m Aoflex lenses which had then just become available, (specification R & L 8.80: 15.00 -10.25). These were collected in January 1975, and as anticipated, the new lenses immediately gave improved comfort and vision. They remained successful, with proper cleaning and maintenance, until March 1976, by which time they had once more become 'proteinised', and uncomfortable because of excessive mobility. In April 1976 he developed a sudden 'red eye' which appeared to be a response to the protein on the lens surface, since they could again be worn with comfort after cleaning with Renogel. In June, the right lens was damaged, although Mr G A continued to wear it in spite of mild discomfort. On this occasion, a large Hydroflex lens was re-ordered, of specification 9.00:15.50 -11.00. A larger overall size was used, to try and maintain greater stability on the cornea. In July 1976, the patient arrived with an extremely severe 'red eye' reaction. This had been precipitated by his falling asleep for about two hours without removingthe lenses and required treatment by one of the London eye hospitals. Nevertheless, he was able to resume contact lens
MrGA This patient was originally examined in 1973, when in great distress from a pair of haptic lenses fitted some 20 years earlier in Scotland. His left lens he wore all day, in spite of constant irritation, whereas the right he was obliged to remove half way through the day, when he could no longer tolerate the discomfort. Both lenses were giving heavy apical touch, and the long term consequence of this had been scarring of the right cornea, and extensive vascularisation of the left, with vessels extending as far as the pupil area. He had no spectacles, despite the fact that when the corneas returned to some degree of normality his Rx proved to be - 1 3 . 0 0 / - 2 . 5 0 in each eye. He refused to consider wearing glasses and to this day has never had the prescription made up. He had tried corneal lenses a few years previously without success, so that there was no clinical alternative but to fit him with soft lenses. High water content lenses were not used because of his rather large clumsy hands and the anticipated risk of breakage. It was considered most appropriate to fit him with the smallest and thinnest lenses available at that time and he was therefore fitted with Bausch & Lomb 'C' Series. The lenses had a power of -11.50D, and although the PAR of 6.70mm was very steep they were nevertheless quite mobile on the cornea ('K' 8.05/ 7.50). This has proved consistent with most of his subsequent fittings, which have also moved on the eye somewhat more than normal. The first, but minor, problem arose after only
37
wear after about 10 days. By September 1976 the new right lens had been damaged, and in October, a new left Hydroflex of the same specification was ordered, to replace the surviving Aoflex which had by then developed large rhulberry-type deposits, which could not be removed by chemical cleaning. In November, he was again experiencing mild discomfort: this was thought to be a reaction to his disinfecting solution, since scattered punctate staining was seen in both eyes. The lenses were cleaned for him, and he was instructed to use a different brand of solution. Originally, he had boiled his lenses and this was probably a contributory factor to their rapid deterioration. In February 1977 Mr G A was again seen with sore red eyes, and the opportunity was taken to fit him with an altogether new type of lens, made of silicone. As has been shown, this patient has had a long history of red eyes, spoiled lenses and other associated problems with several types of lens. This implies no particular criticism of the lenses, because the difficulties arose as much from what the patient did to the lenses, as the lenses did to hiin. Silicone lenses were considered worthwhile trying for a variety of reasons. Their high tensile strength should eliminate the breakage problem; their negligible water content and proven physiological inertness should help with the red eyes; and the lack of need for sterilisation procedures required by soft lenses, and the ease of cleaning, should avoid the build-up of surface deposits. The Silflex lenses prescribed were of specification 8 . 0 0 : 1 2 . 7 0 - 1 1 . 5 0 and these lenses are still currently being worn. The visual acuity is more stable and slightly improved over soft lens vision, and so far there have been no red eyes or broken lenses.
another three times before a satisfactory replacement was obtained, although the original specification had been requested. The right lens then broke in April 1975, and the patient was tried with Ultra-thin Bausch & Lomb ' F ' Series lenses, but these failed to give adequate centration. He was therefore refitted with Hydroflex/m lenses of specification 7.90: 12.50 - 4 . 7 5 . Nothing was then seen o f Mr A A until M a y 1976, when he was observed to have slight vascularisation in both eyes associated with the reappearance of the superior arcuate staining first seen in April 1974. This condition has been termed epithelial hypertrophy, or epithelial splitting, and is caused by the downwards mechanical pressure of a relatively tight upper lid. Between June and September 1976 a whole range of progressively looser and larger fittings was tried, ending up with 8.50: 13.00. However, during this period, wearing time had gradually fallen from all day to only six to eight hours, with no improvement at all in the appearance of the cornea. In fact, only two hours of wear was sufficient to produce staining. In October 1976 a continuous wear lens was tried but on a strictly limited, daily wearing schedule, the intention being that the softness of the material might cure the staining, and the high oxygen permeability might help the vascularisation. This was then regarded as a last resort and it did give satisfactory results for about one month.. After this time, unfortunately, the staining re-appeared; the appearance was more superficial and diffuse, covering a rather greater area of the superior cornea. In February 1976, Silflex lenses were again tried, as a last, last resort, before contact lens wear would have to be discontinued. The patient has shown a remarkable improvement since this time. Not only has the arcuate staining completely disappeared, but the extremely high oxygen permeability of the silicone material has allowed the vascularisation to recede to a considerable degree. The greater rigidity of the silicone lens affords protection to the vulnerable superior area " of the cornea.
MrAA
The second patient was also fitted in mid 1973. but for purely cosmetic reasons. Spectacle Rx was R & L 4.50 DS and 'K' readings 7.60/7.50. He was also originally fitted with Bausch & Lomb 'C' Series, of functional power - 4 . 0 0 . Everything proved satisfactory until April 1974, when slight superior arcuate staining was observed in both eyes. By May 1974, both lenses were chipped on the edges and badly discoloured, and he was therefore refitted with 70% water content, semiscleral lenses, of specification R & L 8 . 4 0 : 1 4 . 5 0 -4.50. Vision was found to be superior with these, especially for near vision. He was seen again in September, 1974, complaining that the left eye was irritating. The left lens had been damaged, and was re-ordered. In fact it had to be re-ordered
In conclusion, these two case histories have tried to show that a minority of soft lens patients will become frequent and regular visitors to one's practice. On some occasions they will arrive with an acute problem requiring immediate action, as typified by the first patient; on others, insidious changes may be observed, as typified by the second patient. Both cases ultimately required the introduction of a completely new type of lens, in this form of silicone, before satisfactory wear could be possible.
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three weeks when the left lens had to be replaced because of a rust spot. Everything then went well until April 1974. By this time the left lens had become excessively loose and unstable on the cornea. It was badly discoloured and the surface was cracked and crazed, requiring replacement. In May 1974, that is just one month later, the patient complained of irritation of the left eye. It was very injected, with peripheral arcuate staining. Lenses were left out for three days, and he was instructed to use the newly introduced enzymatic protein tablets on a regular basis. This he apparently failed to do, and in August 1974, Mr G A was again seen with sudden discomfort in the left eye. Both lenses were badly discoloured, and follicles were seen on the palpebral conjunctiva of the left upper lid. No staining was evident on this occasion. By December 1974, both of the Bausch & Lomb lenses were worn out, and the patient was refitted with 15.00m Aoflex lenses which had then just become available, (specification R & L 8.80: 15.00 -10.25). These were collected in January 1975, and as anticipated, the new lenses immediately gave improved comfort and vision. They remained successful, with proper cleaning and maintenance, until March 1976, by which time they had once more become 'proteinised', and uncomfortable because of excessive mobility. In April 1976 he developed a sudden 'red eye' which appeared to be a response to the protein on the lens surface, since they could again be worn with comfort after cleaning with Renogel. In June, the right lens was damaged, although Mr G A continued to wear it in spite of mild discomfort. On this occasion, a large Hydroflex lens was re-ordered, of specification 9.00:15.50 -11.00. A larger overall size was used, to try and maintain greater stability on the cornea. In July 1976, the patient arrived with an extremely severe 'red eye' reaction. This had been precipitated by his falling asleep for about two hours without removingthe lenses and required treatment by one of the London eye hospitals. Nevertheless, he was able to resume contact lens
MrGA This patient was originally examined in 1973, when in great distress from a pair of haptic lenses fitted some 20 years earlier in Scotland. His left lens he wore all day, in spite of constant irritation, whereas the right he was obliged to remove half way through the day, when he could no longer tolerate the discomfort. Both lenses were giving heavy apical touch, and the long term consequence of this had been scarring of the right cornea, and extensive vascularisation of the left, with vessels extending as far as the pupil area. He had no spectacles, despite the fact that when the corneas returned to some degree of normality his Rx proved to be - 1 3 . 0 0 / - 2 . 5 0 in each eye. He refused to consider wearing glasses and to this day has never had the prescription made up. He had tried corneal lenses a few years previously without success, so that there was no clinical alternative but to fit him with soft lenses. High water content lenses were not used because of his rather large clumsy hands and the anticipated risk of breakage. It was considered most appropriate to fit him with the smallest and thinnest lenses available at that time and he was therefore fitted with Bausch & Lomb 'C' Series. The lenses had a power of -11.50D, and although the PAR of 6.70mm was very steep they were nevertheless quite mobile on the cornea ('K' 8.05/ 7.50). This has proved consistent with most of his subsequent fittings, which have also moved on the eye somewhat more than normal. The first, but minor, problem arose after only
37
wear after about 10 days. By September 1976 the new right lens had been damaged, and in October, a new left Hydroflex of the same specification was ordered, to replace the surviving Aoflex which had by then developed large rhulberry-type deposits, which could not be removed by chemical cleaning. In November, he was again experiencing mild discomfort: this was thought to be a reaction to his disinfecting solution, since scattered punctate staining was seen in both eyes. The lenses were cleaned for him, and he was instructed to use a different brand of solution. Originally, he had boiled his lenses and this was probably a contributory factor to their rapid deterioration. In February 1977 Mr G A was again seen with sore red eyes, and the opportunity was taken to fit him with an altogether new type of lens, made of silicone. As has been shown, this patient has had a long history of red eyes, spoiled lenses and other associated problems with several types of lens. This implies no particular criticism of the lenses, because the difficulties arose as much from what the patient did to the lenses, as the lenses did to hiin. Silicone lenses were considered worthwhile trying for a variety of reasons. Their high tensile strength should eliminate the breakage problem; their negligible water content and proven physiological inertness should help with the red eyes; and the lack of need for sterilisation procedures required by soft lenses, and the ease of cleaning, should avoid the build-up of surface deposits. The Silflex lenses prescribed were of specification 8 . 0 0 : 1 2 . 7 0 - 1 1 . 5 0 and these lenses are still currently being worn. The visual acuity is more stable and slightly improved over soft lens vision, and so far there have been no red eyes or broken lenses.
another three times before a satisfactory replacement was obtained, although the original specification had been requested. The right lens then broke in April 1975, and the patient was tried with Ultra-thin Bausch & Lomb ' F ' Series lenses, but these failed to give adequate centration. He was therefore refitted with Hydroflex/m lenses of specification 7.90: 12.50 - 4 . 7 5 . Nothing was then seen o f Mr A A until M a y 1976, when he was observed to have slight vascularisation in both eyes associated with the reappearance of the superior arcuate staining first seen in April 1974. This condition has been termed epithelial hypertrophy, or epithelial splitting, and is caused by the downwards mechanical pressure of a relatively tight upper lid. Between June and September 1976 a whole range of progressively looser and larger fittings was tried, ending up with 8.50: 13.00. However, during this period, wearing time had gradually fallen from all day to only six to eight hours, with no improvement at all in the appearance of the cornea. In fact, only two hours of wear was sufficient to produce staining. In October 1976 a continuous wear lens was tried but on a strictly limited, daily wearing schedule, the intention being that the softness of the material might cure the staining, and the high oxygen permeability might help the vascularisation. This was then regarded as a last resort and it did give satisfactory results for about one month.. After this time, unfortunately, the staining re-appeared; the appearance was more superficial and diffuse, covering a rather greater area of the superior cornea. In February 1976, Silflex lenses were again tried, as a last, last resort, before contact lens wear would have to be discontinued. The patient has shown a remarkable improvement since this time. Not only has the arcuate staining completely disappeared, but the extremely high oxygen permeability of the silicone material has allowed the vascularisation to recede to a considerable degree. The greater rigidity of the silicone lens affords protection to the vulnerable superior area " of the cornea.
MrAA
The second patient was also fitted in mid 1973. but for purely cosmetic reasons. Spectacle Rx was R & L 4.50 DS and 'K' readings 7.60/7.50. He was also originally fitted with Bausch & Lomb 'C' Series, of functional power - 4 . 0 0 . Everything proved satisfactory until April 1974, when slight superior arcuate staining was observed in both eyes. By May 1974, both lenses were chipped on the edges and badly discoloured, and he was therefore refitted with 70% water content, semiscleral lenses, of specification R & L 8 . 4 0 : 1 4 . 5 0 -4.50. Vision was found to be superior with these, especially for near vision. He was seen again in September, 1974, complaining that the left eye was irritating. The left lens had been damaged, and was re-ordered. In fact it had to be re-ordered
In conclusion, these two case histories have tried to show that a minority of soft lens patients will become frequent and regular visitors to one's practice. On some occasions they will arrive with an acute problem requiring immediate action, as typified by the first patient; on others, insidious changes may be observed, as typified by the second patient. Both cases ultimately required the introduction of a completely new type of lens, in this form of silicone, before satisfactory wear could be possible.
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