Patients Histories and Care Schedules in Ophthalmology - Case Study Example

Patients’ Histories and Care Schedules in Ophthalmology Patient history: The case of a 12-year-old myopic boy was first seen in 2004 for vision check up. He continued wearing myopic spectacle for the next three years. A progression in myopic reduction, at a rate of 1.25 DS, became a concern between years 2007 and 2008. In order to control myopia, orthokeratology (OK) treatment was suggested. At that time, his refraction was R -3.50 -0.25 x 110 (VA 6/7.5) and L -3.75 -0.50 x40 (VA 6/7.5). The first pair of OK was dispensed in 2008 with the advice to wear it overnight on a daily basis. Since then, after care visits were arranged on regular schedule. Subsequently, another pair of lenses was required and he was doing well. Current lens and care schedule: The boy kept wearing the current pair of OK since the beginning of this year (2010) on a daily basis overnight. The design is CRT, manufactured by Menicon Z material with the following parameters: R 8.1/ +0.50/ 550-34 CAS L 8.2/ +0.50/ 575-34 CAS His mother has taken the commitment for lens insertion at night before sleeping, removal at morning and proper cleaning and storage. Boston cleaner was used for cleaning, saline for rinsing and Boston advance conditioning solution for storing. Current visit: This is one of the after care visits. The patient comes with his mother and states no complaints. His mother informs the optometrist that the entire family is going to spend the next two months overseas and the departure date is during this week. Clinical Findings and Observations: Unaided visual acuity was R: 6/6-, L: 6/7.5, while unaided binocular vision was 6/6-. Over refraction was R: -0.25 DS (VA 6/6) and L: -1.25 DS (VA 6/6). When the lens measurements are taken, it is revealed that lenses have been interchanged and the patient has been wearing incorrect lenses for the last six months. This explains the difference in unaided visual acuity between the eyes and the lack of correction in left eye. Slit lamp evaluation shows a Dystrophy like change in the cornea, more significant on the right eye with no limbal injection. Its location is in mid periphery corneal stroma extending from 9 to 4 o’clock in the right eye and from 10 to 2 o’clock on the left. Anterior segment images of OCT show white opacity in anterior stroma. Plans: The patient needs to discontinue wearing OK lens for the next period because of the dystrophy change noted in the cornea. Besides, it will be difficult to monitor the corneal change since the patient will be spending holidays overseas. Therefore, the patient has been advised to cease wearing lenses and using disposable contact lenses until regression of OK treatment occurs. The powers of daily contact lenses, to be worn in the same order for both eyes, are as follows: -0.75 DS, -1.25 Ds, -2.00 DS, -2.50 DS, -3.00 DS. In addition, the patient has been provided a pair of -3.50 DS monthly contact lenses to be worn on a daily basis, besides his old spectacle until the next appointment. Prognosis: The patient has undergone OK treatment in an attempt to control progressive myopia. On expiry of two years, stromal change has been noticed on mid peripheral cornea that coincides with the treatment zone margins. It is localised only on the mid periphery and does not approach the pupil margins. So, the vision is not affected. Hence, suspending OK treatment may help stabilisation of this defect and retard its development. In fact, the prognosis of this effect is perhaps not predictable. Therefore, continuous check up is required after ceasing OK, which is currently discerned as the possible cause. On the other hand, OK procedure is reversal and it is expected to retain original myopia once the patient ceases wearing lens. However, studies have shown that there are significant individual differences in terms of rate of regression1. Also, the regression has been complete in some patients, while in the case of others it has been partial. Either way, the average regression is between -0.50 DS to -0.75 DS per day1. Thus, it can be inferred that regression is expected, but the rate and endpoint cannot be determined. Stromal change in the cornea is also not predictable. Maintaining review visits in this case is not only absolutely essential but it is also critical for clinical monitoring. Discussion: OK has been an effective procedure not only for myopia reduction, but also for myopia control in children. However, long-term effects of the treatment are becoming a matter of increasing concern. This is because of the reported adverse effects that were associated with wearing OK lens overnight. These complications include corneal ulcers2, Acanthamoeba and Pseudomonas keratitis3. Besides, there also have been reports of less serious adverse effects such as mid peripheral pale brown or white pigmented ring in the basal corneal epithelium4, central corneal staining5 and lens binding5. The reported change in this case may be one of less severe episodes because it was not infectious and did not affect the vision. The patient was happy and asymptomatic. Therefore, medical intervention is not required at this stage, but ceasing OK is recommended to avoid any further development. However, follow up visits are required to detect any changes that may need medical attention. Since the patient is going to spend vacation overseas, the next possible check up visit has been booked after eight weeks. Summary: This is the case of a 12-year-old boy who has been undergoing OK procedure to control the progression of myopia. He visited the clinic for a review before departing for overseas on a two-month vacation. He has no visual or ocular complaints. Clinical findings indicate that lenses were worn incorrectly and visual acuity was not similar in the eyes. In addition, whitish stromal change was identified in mid peripheral cornea. Thus, OK treatment needs to be suspended to monitor the cornea. The patient has been advised to wear soft contact lenses and his old spectacles during this period. The next appointment for further clinical observations and assessment has been set after 8 weeks, on his return from vacation. References: 1- Swarbrick HA. Orthokeratology review and update. Clin Exp Optom 2006;89:124-43. 2- Young AL, Leung ATS, Cheng LL, Law RWK, Wong AKK, Lam DSC. Orthokeratology lens-related corneal ulcers in children: a case series. Ophthalmology 2004; 111: 590–5. 3- Watt K, Swarbrick HA. Microbial keratitis in overnight orthokeratology: review of the first 50 cases. Eye Contact Lens. 2005;31:201-20 4- Cho P, Chui WS, Mountford J, Cheung SW. Corneal iron ring associated with orthokeratology lens wear. Optometry and Vision Science 2002;79:565-568. 5- Cho P, Cheung SW, Edwards MH, Fung J. An assessment of consecutively presenting orthokeratology patients in a Hong Kong based private practice. Clinical and Experimental Optometry 2003;86 :331-338. Case (4) Patient History: This patient is a 14-year-old girl student who has been wearing orthokeratology (OK) overnight for four years. Originally myopic, with no astigmatism, she was an ideal candidate for OK treatment. Her previous spectacle measurement was R -3.50 DS (VA 6/4.8) and L: -1.75 DS (6/4.8). The most recent review visit occurred 6 months ago. She was doing well with no complaints. Clinical evaluation of visual acuity and anterior segment showed no remarkable findings. Current Lenses and Care Schedule: The age of current lenses is four and two years respectively for the right and left eyes. Parameters of the lenses are as follow: R: 42.75/ -3.25 (0.5 e)/ 9.1 R: 42.50/ -3.50 (0.6 e)/ 9.1 The patient is independent in the matters of lens insertion, removal and care. She cleans the lenses every day after removal and then stores them until next use at night. The average wearing time is approximately eight hours every night. Current Visit: The patient has attended the Optometry clinic for regular follow up. Her main complaints are redness in eyes, itching and poor vision at near. She also states that in order to read clearly she has to keep the reading material close to her eyes, which causes difficulty in the class. She is concerned because a singing exam is due at the end of the week and the song lyrics would be in front of her during singing. Clinical Findings and Observations (1): Clinical findings shows un aided visual acuity of R: 6/24, L: 6/24 and 6/19 in both eyes, which indicate reduced vision by more than two lines as compared to the last visit. Subjective refraction is R: -1.00/ -2.75 x 92 (VA 6/6) and L: -0.75/ -3.00 x 81 (VA 6/6), which shows induced astigmatism. Slit lamp assessment indicates mild allergic conjunctivitis, while topography maps show uneven and distorted surface with general flatness. Plans (1): The patient is asked to discontinue OK wearing and daily disposable toric lenses are given. In addition, zaditor has been recommended twice daily as well as cold compress to reduce itching and redness. She has been given the next appointment after three days to monitor the change after ceasing OK and to ensure that she will be able to perform the singing test. Prognosis (1): The symptoms of allergic conjunctivitis are expected to recede in the next few days of using zaditor drops and cold compress. In terms of vision expectations, ceasing OK will cause regression of myopia but the rate and end point of regression is unpredictable. The most critical concern in this case is the induced astigmatism but, hopefully, original shape of cornea can be retained by discontinuing OK. Clinical Findings and Observations (2): The patient returns to the clinic after three days, relieved of the symptoms of allergy and with improved vision. Clinical examination shows an improvement of one line in unaided visual acuity. Subjective refraction remains at: R: -1.75/ -1.50 x 90 (VA 6/4.8) and L: -1.50/ -1.50 x 85 (6/4.8), which indicate improved aided visual acuity, reduction in induced astigmatism and increase of myopia as a result of OK discontinuation. Topography maps are slightly uneven but show 1.00 D of corneal astigmatism in both eyes. Plans (2): The patient has been provided with additional disposable toric lenses for daily use to assist vision in school and during exam. Next visit for review has been booked after two weeks for clinical evaluation and refitting OK if the refraction becomes stable by then. Prognosis (2): Usually, wearing of OK lens does not induce astigmatism. Therefore, the amount of astigmatism reduction cannot be predicted. On the other hand, it may increase myopia and the patient may return with more myopia and less astigmatism. The other possible scenario is that the patient may appear after two weeks with more myopia but same amount of astigmatism. Discussion: One of the major issues that is addressed by using reverse geometry design in modern OK is induced astigmatism. Unlike traditional OK treatment, modern OK design enhances stability and lens centration1. Thus, current OK design is not likely to induce astigmatism in non-astigmatic eyes2. In spite of this, some studies report induced astigmatism over six months3 and one year4 of OK treatment in children and adolescents. It was found that this amount reversed when old lens is exchanged with a new one, or when the wearing time switched from overnight to overday3. In fact, the findings of this study seem questionable because the amount of induced astigmatism is not acknowledged, and procedures to address this problem are not explained fully. Therefore, it transpires that there is a lack of firm ground to refer to in terms of induced astigmatism as a result of OK treatment. The suggested method to manage this case is to cease current OK immediately and continue follow up visits to evaluate changes in astigmatism over the time. Once refraction gets stabilised, the patient can refit OK if the residual astigmatism disappears. It has to be taken into consideration that the residual astigmatism is against the role that usually responds less to OK compared to with the role astigmatism. Hence, other approaches of correction such as toric soft contact lenses or spectacles can be used if OK is no longer feasible. Another approach that seems appropriate is toric OK although the efficacy of this design is still under investigation. Summary: This is the case of a 14-year-old girl student who had undergone OK treatment for the last four years and came to Optometry clinic for routine check up. Her main complaints included redness, itching and decreased vision at far. Clinical findings show allergic conjunctivitis, reduced unaided visual acuity and irregular corneal contour. Subjective refraction indicates induced astigmatism in both eyes. The action plan has recommended zaditor and cold compress to relieve conjunctivitis allergy. The patient was asked also to cease OK to reverse back astigmatism. She was given an appointment after three days. Observations after three days showed relief in allergy, reduced residual astigmatism and improved aided visual acuity. Apart from this, myopia was retained as a result of OK discontinuation. Another appointment was given after two weeks for further clinical evaluation and to check stability of refraction to refit with OK or provide other suitable correction. 1- Swarbrick H.A. Orthokeratology (corneal refractive therapy): what is it and how does it work?. Eye Contact Lens. 2004;30(4):181–185 2- Cheung SW, Cho P, Chan B. Astigmatic Changes in Orthokeratology. Optometry & Vision Science. 2009;86(12):1352-8. 3- Fan L, Jun J, Jia Q, Wangqing J, Xinjie M, Yi S. Clinical study of orthokeratology in young myopic adolescents. International Contact Lens Clinic.1999; 26(5):113-6. 4- Wang J, Chiou C-J, Fung J-F, Chu J-M, Hu F-R. One-Year Outcome of Overnight Orthokeratology in Taiwanese Children and Adolescents. Tzu Chi Med J. 2005;17(1):27-33. Case (5) Patient history: This patient is a 50-year-old male who visited to Optometry clinic for a routine check up. He was an orthokeratology (OK) lens wearer in the right eye for distance correction while the left was corrected for near. Because his daughter has had a successful experience with OK lenses, he requested this option of presbyopia treatment. At that time, clinical findings showed subjective refraction R: -2.00/ -0.25 x 130 (VA 6/6), L: -2.00/ -0.25 x 180 (VA 6/6) and an additional near lens of +2.00 DS, which indicated that he was a good candidate for OK. The treatment was commenced last year and the patient was happy with the outcome of his sight. He had no complications or complaints. Current lens and care schedule: His dominant eye was the right eye, so it was fitted with Contex OK lens of the following parameters: R: 43.47 dk 0.4 e0.83 /0.09 sag 70/ 12.43 The lens is worn 8 hours every night and removed carefully by using a sucker in the next morning. It is reportedly cleaned each time and rubbed with cleaning solution and rinsed in saline and then stored in the lens case. Current visit: This visit was one of the scheduled follow up visits due every 6 months to check vision, ocular health and for disinfection system application on his lens that is usually done in the practice. The patient attended the clinic with no complaints or serious complications. Clinical Findings and Observations: Unaided binocular visual acuity at distance was 6/6+, while near vision was N4@40 cm. This indicated a very good vision at both distances. The patient was asked to move the reading material closer and further away to identify clearer points, which was found to be about 40 cm. The Retinoscopy result showed R: +0.25 DS and L: -2.00 DS with bright reflex that represented a clear ocular media. Topography map showed a flat central treatment zone that exceeded the pupil margins, whereas the steepening ring surrounding the treatment zone was found incomplete in formation. Plans: The patient can continue wearing the same OK lens in the right eye to create monovision correction for presbyopia. The next review visit was scheduled to be after six months. Prognosis: This patient has simple myopia and presbyopia. So far it relates to myopia, it is unlikely to develop during presbyopic years for more than 0.50 DS per decade1. Hence, distance refraction would be stable over the time. On the other hand, presbyopia is expected to increase gradually. If this occurs, additional plus lens can be used for the left eye in the form of contact lens or a spectacle. Anyhow, this has to be discussed with the patient later to meet his needs. Discussion: Monovision is one of the options to correct presbyopia, which is based on the principle of correcting dominant eye for distance and non-dominant for near visions. As seen in this patient, the right eye was corrected by OK lens for distance vision and power was required for the left. This is because the required additional lens compensates the amount of myopia in the eye resulting plano power to clarify near vision. One of the main advantages of this method is that it provides simultaneous corrected vision at distance and near. Therefore, the patient would be able to achieve tasks that required clear vision at distance and near at the same time like reading a book in a public park. The second advantage of using OK in this patient is the freedom of any kind of visual correction during the day. Thus, the patient would be able to perform even more activities that would be difficult to perform with spectacle and contact lenses. These benefits may improve his quality of life since the patient can achieve a variety of complex activities to meet his needs. On the other hand, topography map of the right eye showed a steep ring surrounding the flat central treatment zone. This actually can be seen as a smiley face map that is usually associated with flat fitting. However, this could be in the middle between ideal fitting and flat fitting and perhaps closer to ideal because the ring was almost complete. Evaluating the lens fitting with slit lamp and fluorescent can support this. Hence, it appears that sometimes there may be no absolute answer but achieving balance is required to judge on lens fitting or other clinical situation. Summary: This patient is a 50-year-old male who was a known case of presbyopia corrected by monovision method. His right eye was corrected for distance by OK lens since one year, while his left was already corrected for near because he did not require power glasses for near vision. He attended the Optometry clinic for routine visit and to request lens disinfection system. He was happy with his experience and had no complaints or complications. The clinical evaluation showed no remarkable findings. Therefore, the current treatment can be continued and a review after six months was suggested. Check up visits is essential to monitor ocular health and any change in presbyopia since it is expected to increase. Reference: 1- Grosvenor TP.Primary care optometry. St. Louis (Miss.): Butterworth Heinemann, Elsevier; 2007. Read More