Comparing the Tonojet disposable tonometer with the traditional Goldmann tonometer in glaucomatous and non-glaucomatous eyes.

Applanation tonometry is widely performed as the most accurate method of measuring intraocular pressure in the clinical setting. Disposable tonometer heads reduce the risk of transmitting infection during applanation and eliminate tonometer head cleaning, which is time-consuming. We performed a study to investigate whether the Tonojet disposable tonometer (Luneau, France) gave comparable intraocular pressure measurements to the standard Goldmann tonometer produced by Haag Streit (Switzerland). The study was performed in a busy general secondary referral ophthalmology clinic in Beaumont Hospital over a 15-day period. We measured intraocular pressure with the Goldmann and Tonojet tonometers in 293 eyes. Patients were randomised as to which tonometer was used first. A diagnosis of glaucoma or ocular hypertension was noted. Central corneal thickness (CCT) was measured. The measurements taken with the Tonojet were on average 2.2 mmHg lower than corresponding measurements taken with the Goldmann applanation tonometer head. The bias was present over the entire range of pressures. The 95 % limits of agreement between the two tonometers ranged from -5.9 to +1.4 mmHg. In the cohort of eyes with ocular hypertension/glaucoma the difference was significantly higher (2.8 vs. 2.1 mmHg). The bias was independent of CCT. We found that the Tonojet disposable tonometer tends to underestimate intraocular pressure compared with the Goldmann. The bias is non-systematic, present over the entire range of pressures and independent of corneal thickness. We conclude that the Tonojet is not sufficiently accurate to constitute a suitable alternative to the Goldmann.

Polyacrylic acid gel in patients with dry eyes: a randomised comparison with polyvinyl alcohol.

PURPOSE: To compare the safety and efficacy of polyacrylic acid 0.2% (PAA) gel and polyvinylalcohol 1.4% (PVA) in the treatment of patients with dry eyes. METHODS: Eighty-nine patients with dry eyes were randomly allocated to treatment with either PAA (48) or PVA (41) in a prospective, investigator-masked study in two centres. The parameters assessed were daily frequency of instillation of the study medications, ocular signs and symptoms, tear film break up time, Schirmer's test values, local tolerance and global assessment of the improvement following treatment. RESULTS: The two groups were similar in patient demographics and study parameters at baseline. The total score of symptoms (gritty or foreign body sensation, burning sensation, dry eye sensation, photophobia, others) and signs (conjunctival hyperaemia, ciliary injection, corneal and conjunctival epithelial staining) was reduced significantly more by treatment with PAA than with PVA at both three and six weeks (p < 0.0001). The daily frequency of instillation of PAA was significantly less than that PVA on 38 of the 41 (93%) study days. Both PAA and PVA were safe and equally well-tolerated except for blurred vision, usually mild and transient, on PAA. On global assessment of the improvement in their dry eye condition, significantly more PAA patients felt better on treatment at six (p = 0.02) weeks compared with those on PVA. CONCLUSIONS: Polyacrylic acid gel was as safe as and more effective than polyvinylalcohol in the treatment of patients with dry eyes.

Topographical analysis of ablation centration after excimer laser photorefractive keratectomy and laser in situ keratomileusis for high myopia.

PURPOSE: To evaluate the ablation centration after photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) for high myopia and to assess the association between decentration and best corrected visual acuity (BCVA), glare, monocular diplopia, and halo phenomenon. SETTING: Mater Private Hospital, Dublin, Ireland. METHODS: Corneal topography was used to analyze centration in two groups of patients with myopia of more than 6.0 diopters: 18 had PRK and 18, LASIK. A standardized questionnaire assessed the preoperative and postoperative prevalence of glare, monocular diplopia, and halo phenomenon. RESULTS: "Significant" ablation decentration (0.5 mm) in the LASIK group (1.33 mm) was almost twice that in the PRK group (0.75 mm). Glare increased from 27% preoperatively to 42% in the PRK group; monocular diplopia increased in the LASIK group. Halo phenomenon decreased after both procedures. CONCLUSION: Laser in situ keratomileusis represents a step forward in the surgical correction of high myopia, but the accuracy of the corneal ablation location must be improved. Suction ring fixation of the globe or real time tracking systems may help improve centration.

Laser intrastromal keratomileusis for high myopia and myopic astigmatism.

BACKGROUND: Laser intrastromal keratomileusis (LASIK) is an evolving technique which enables high degrees of myopia (> 8.0 dioptres) and myopic astigmatism to be corrected. This paper describes initial experience with this procedure. It also details the methodology, the results, the problems encountered, and discusses retreatment procedures. METHODS: 51 eyes (48 primary cases and three retreatments) underwent LASIK for simple myopia or compound myopic astigmatism. After the keratotomy was fashioned with a Chiron corneal shaper, the ablation was performed with either a Summit or Meditec excimer laser. The actual preoperative astigmatism ranged from -0.5 D to -6.0 D (in the astigmatic myopic LASIK (AML) series), while the range of preoperative myopia in the combined myopic LASIK (ML) and AML series was -8.0 D to -37.0 D. Of the ML cases, group 1 (-8.0 to 15.0 D (dioptres)), group 2 (> -15.0 to -20.0 D), and group 3 (> -20.0 D) had mean preoperative myopia values (spherical equivalent) of -11.26 D, -16.84 D and -27.78 D. The same groupings (1, 2, and 3) for the AML cases had respective values of -9.702, -17.4, and -23.08. In the AML series the mean preoperative astigmatism was -2.109 D. Follow up ranged from 8 to 27 months (mean 15.8 months). Six of the cases required retreatment. RESULTS: There was a reduction in best corrected visual acuity (BCVA) (of 1 Snellen line) in seven of the primary cases (14.5%) (three in the ML group and four in the AML group), and in one of the retreatment cases. The BCVA improved in 28 cases (58%) in the primary treatment group. The mean correction attempted (spherical equivalent) for the ML groups 1, 2, and 3 was 10.51 D, -14.5 D, and -27.78 D, versus a mean correction achieved of -9.445 D, -15.625 D, and -21.571 D. Similarly, for the AML groups, attempted correction values were -9.702 D, -17.4 D, and -23.08 D, while the values achieved were -6.95 D, -51.425 D, and -15.708 D. Regression was minimal and stabilisation of the refractive result was achieved in all groups, except group 3 of the ML series, by the 3 month examination period. The mean postoperative astigmatism in the AML series was -0.531 D. Vector analysis of the AML series showed that the mean surgically induced astigmatism was +0.93 D. The most common complication encountered was undercorrection, which occurred in 35 cases-23 cases in the ML group and 12 cases in the AML series. Twenty eight per cent of the ML cases, and 25% of the AML cases were within plus or minus 1.5 D of the attempted refraction. CONCLUSION: For the correction of high myopia and myopic astigmatism, LASIK results in less postoperative pain and relatively little subepithelial haze compared with high myopic photorefractive keratectomy. Furthermore, a stable refraction and reasonably predictable outcome occurs much earlier. High myopia up to -37.0 D can be corrected, albeit with some limitations at the extremes of myopia-in terms of the amount of myopia correctable; this represents a limitation of the technique. Retreatment is a technically straightforward and effective way to treat undercorrection. Undercorrection, the main complication seen in our series, should become less common when the ablation algorithms are further refined.

Atropine penalisation versus occlusion as the primary treatment for amblyopia.

AIMS/BACKGROUND: Pharmacological penalisation of non-amblyopic eyes is an infrequently used alternative to occlusion for treating amblyopia. The authors compared the efficacy of atropine penalisation and that of occlusion as a primary treatment for amblyopia. METHODS: Thirty six newly diagnosed patients with amblyopia were allocated to two groups for treatment. Eighteen patients in each group were treated either with atropine penalisation (group A) or occlusion therapy (group P). RESULTS: There was a statistically significant improvement in visual acuity in both groups treated. In group A improvement of the geometric mean visual acuity of the amblyopic eye was from 6/50 to 6/11 (p < 0.001). In group P improvement of the geometric mean visual acuity was from 6/60 to 6/19 (p < 0.001). In group A non-compliance with treatment was only 6% (2/18). Non-compliance in group P was 45% (8/18) at some stages of the treatment. Neither group produced an incidence of occlusion amblyopia. CONCLUSIONS: In this study atropine penalisation has been shown to be as effective as occlusion therapy in the treatment of amblyopia. Patient acceptance of atropine penalisation was superior to that for occlusion therapy as was shown by the compliance rate. Atropine treatment was also advantageous in that compliance could be readily checked by inspection.

Regression after photorefractive keratectomy for myopia.

OBJECTIVE: To evaluate the effect of topical steroid treatment in eyes that showed refractive regression after photorefractive keratectomy (PRK) to correct myopia. SETTING: Mater Private Hospital, Dublin, Republic of Ireland. METHODS: In this prospective study with a minimum of 6 months follow-up, 289 eyes were treated over 2 1/2 years. Of these eyes, 23 had myopic regression of 0.75 diopters (D) or more. Topical steroid treatment was given to reverse the regression. Refraction and uncorrected visual acuity before and after treatment were measured. RESULTS: Twelve eyes in the regression group had at least 18 months of follow-up. At the final examination, eight of these eyes had an uncorrected visual acuity of 20/40 or better; six were within 1.00 D of intended refraction. CONCLUSION: Refractive regression after PRK for myopia was permanently reversed in some eyes; final stable refraction was close to the intended value in about half.

Herpes simplex keratitis in children.

Ophthalmic findings are reported in 31 eyes of 28 children with herpes simplex keratitis. Twenty two had dendritic ulcers, and nine had geographic ulcers or disciform stromal keratitis. After resolution of keratitis, 80% (19/22) of children with dendritic ulcers achieved corrected visual acuity of 6/9 or better, 50% (11/22) had induced astigmatism, 45% (9/22) had one to five recurrences. In the group with geographic or disciform lesions, 89% (8/9) had reduced corrected vision, 78% (7/9) had induced astigmatism which was predominantly against the rule, and 87% (7/9) had one to six recurrences.

Skeletal tuberculosis.

Skeletal tuberculosis is an uncommon form of tuberculosis. During the period 1977-87, the number of cases diagnosed in two Dublin hospitals has remained at a constant level. The present study reports on 36 adults with skeletal tuberculosis and shows more frequent extraspinal involvement than other studies. The long duration of symptoms prior to diagnosis of 10.79 (+/- 8.8) months suggests that tuberculosis is not being considered early in the course of unexplained inflammatory arthritides especially in the elderly patient. The under utilisation of the Mantoux test in diagnosis is also a matter of concern.

Diabetics treated with continuous subcutaneous insulin infusion pumps.

Sixteen insulin-dependent diabetics commenced continuous subcutaneous insulin infusion (CSII) pumps either because of poor control (15 patients), or because of preference (1 patient). The study examined the diabetic control achieved, patients attitudes and CSII pump complications. Statistically significant improvements in HbAlC which fell from a pre-treatment mean of 12.57% to 10.0% at three months (p less than 0.01) and 10.6% at six months (p less than 0.02) were achieved. At nine months the improvement was not statistically significant. Fourteen of the 16 patients wished at the end of one year to continue this treatment. This study reports a low rate of symptomatic hypoglycaemia and infusion site infection. However, there was a large number of cases of ketoacidosis which highlights the need for extreme vigilance in monitoring patients treated by this method.