Effect of laser photocoagulation treatment for diabetic macular oedema on patient's vision-related quality of life.

PURPOSE: To evaluate the effect of laser photocoagulation for diabetic macular oedema (DME) on patients' Vision Related Quality Of Life (VR-QOL) and to investigate associations between changes in self reported VR-QOL and changes in visual acuity following application of laser treatment. METHODS: Prospective cohort study of 55 subjects who underwent laser treatment for DME. Eligible patients with no history of previous laser photocoagulation self-administered the 51-item field-test version of the National Eye Institute Visual Function Questionnaire (NEI-VFQ) prior to treatment and 3 months following the last session of laser application. Visual acuity was measured by means of the Early Treatment of Diabetic Retinopathy (ETDRS) chart. Multi-item scales rating different aspects of VR-QOL were compared prior and after photocoagulation and the change in questionnaire's composite score following treatment was correlated to change in visual acuity and other determinants previously reported as risk factors in the diabetic population. RESULTS: Scale scores associated with general vision, near vision, distance vision, peripheral vision, vision-specific social functioning, vision-specific mental health, expectations for visual function and dependency due to vision were significantly improved following laser treatment. Multivariate models revealed that improvement of the NEI-VFQ composite score was significant in subjects younger than 65 years of age (p = 0.04) who received more laser burns (p = 0.02) and had worse vision-related QOL prior to laser treatment as expressed by the baseline NEI- VFQ composite score (p = 0.03). There was no statistically significant association between change in the composite score following laser treatment and stage of diabetic retinopathy, duration of diabetes or laser settings used during photocoagulation. CONCLUSIONS: Photocoagulation for DME has a beneficial effect on patients' subjective perception of visual function. The use of vision-targeted health status questionnaires in conjunction with the clinical examination appears to provide a more comprehensive overview of individuals' daily well- being following laser treatment.

Correlating intraocular pressure, blood pressure, and heart rate changes after jogging.

PURPOSE: To examine the effects of jogging on intraocular pressure (IOP), blood pressure (BP), and heart rate (HR). METHODS: Twenty-nine healthy individuals-25 athletes and 4 untrained-were studied. IOP, systolic and diastolic BP, and HR were measured before and just after 20 minutes of jogging (submaximal--70%--aerobic exercise). RESULTS: IOP decreased after jogging. Only three individuals had unchanged IOP in one eye and one individual in both eyes. The IOP decrease (1 to 8 mmHg) was statistically significant (p<0.001). BP increased after jogging (systolic: 0 to 60 mmHg, statistically significant changes, p<0.001; diastolic: 0 to 15 mmHg, statistically significant changes, p<0.001). HR increased as well (15 to 80 pulses/min, statistically significant changes, p<0.001). However, there were individuals who presented a significant decrease of IOP and a mild BP rise and vice versa, and also individuals with mild IOP decrease and significant HR change and vice versa. The statistical analysis clearly showed that there are no linear quantitative correlations between BP or HR changes and IOP changes. CONCLUSIONS: IOP decreases after jogging. Changes in BP and HR values have no linear quantitative correlation with IOP decrease.

Brimonidine 0.2% given two or three times daily versus timolol maleate 0.5% in primary open-angle glaucoma.

PURPOSE: To evaluate the efficacy and safety of brimonidine 0.2% two or three times daily versus timolol maleate 0.5% solution twice daily. METHODS: Patients with primary open-angle glaucoma were randomized by Latin square technique to one of the three treatment sequences in this crossover, prospective double-masked trial. Each treatment period consisted of 6 weeks of chronic dosing followed by a diurnal curve for the intraocular pressure measured at 08:00, 10:00, 16:00, 18:00, 20:00, 22:00, and 24:00 hours. Intraocular pressure was measured by applanation tonometry. RESULTS: Thirty patients completed this trial. The average diurnal intraocular pressures in the trial were measured for timolol maleate (17.7 +/- 2.7 mm Hg), brimonidine given three times daily (18.0 +/- 2.2 mm Hg), and brimonidine given twice daily (19.2 +/- 2.4 mm Hg). There was a statistical difference between groups (P <.005). When groups were compared by pairs, three times daily dosing with brimonidine and timolol maleate both reduced the pressure more than twice daily brimonidine at every time point past 10:00 hours and for the diurnal curve (P <.05). In contrast, three times daily brimonidine and timolol maleate were statistically similar for the diurnal pressure, and each time point, except timolol maleate, decreased the pressure more at 16:00 (P =.042). Safety was similar between groups. CONCLUSIONS: This study demonstrated that both timolol maleate twice daily and brimonidine three times daily provide a similar intraocular pressure reduction to each other. Timolol maleate twice daily and brimonidine three times daily provide a greater decrease in pressure in the late afternoon and nighttime hours, compared with brimonidine twice daily.

Macular epiretinal membranes.

Epiretinal membranes (ERM) are a common finding in older patients. Although they may be associated with numerous clinical conditions, most epiretinal membranes occur in the absence of ocular pathology. Patients symptoms range from asymptotic to complaints of severe vision loss and metamorphopsia. Epiretinal membranes are commonly classified according to their density, to the severity of retinal distortion and to associated biomicroscopic changes. Pars plana vitrectomy has been found to be effective in removing ERM from the macula, improving the visual acuity and decreasing metamorphopsia. Both idiopathic and secondary ERMs do well after surgery, although secondary ERMs showed a greater amount of improvement than idiopathic ones. Complications are frequent including accelerated postoperative nuclear sclerosis, retinal breaks and RD, macular edema, RPE and, occasionally, macular hole and hypotony. However only RD involving the macula have a worsening prognosis on final outcome.

Ultrasonographic classification and phacoemulsification of white senile cataracts.

OBJECTIVE: To classify the white senile cataracts and report the results of phacoemulsification of white cataracts. DESIGN: Prospective, noncomparative case series. PARTICIPANTS: One hundred eyes were included. INTERVENTION: White cataracts were examined biomicroscopically before surgery, and their acoustic structure was analyzed with standardized A-scan echography. White cataract surgery was performed with phacoemulsification via a superior temporal near-limbus corneal approach using a bimanual divide-and-conquer or stop-and-chop technique. Patients were followed after surgery for a period of 9 months. MAIN OUTCOMES MEASURES: The A-scan acoustic structure of white cataracts; successful accomplishment of capsulorrhexis; mean phacoemulsification time, power, and energy; intraoperative and postoperative complications of phacoemulsification; and visual acuity at 9 months after surgery. RESULTS: White senile cataracts were categorized into three different types. Type I included intumescent, white cataracts with cortex liquefaction and high internal acoustic reflections (44 eyes), type II included white cataracts with voluminous nuclei, little amount of whitish solid cortex, and low internal acoustic reflections (49 eyes), and type III included white cataracts with fibrosed anterior capsule and low internal echospikes (7 eyes). Circular capsulorrhexis was completed in 79 eyes and was significantly less successful in eyes with type I intumescent, white cataracts compared with type II white cataracts (P = 0.0034). Mean phacoemulsification time and energy were higher in type II and type III white cataracts. Posterior capsule rupture occurred in ten eyes, and three of these eyes were complicated by vitreous loss. In 95 eyes, the posterior chamber lens was implanted in the capsular bag and in five eyes in the sulcus. After surgery, a transient corneal edema developed in 31 eyes. At the final 6-month examination, the mean postoperative visual acuity was 20/30. CONCLUSION: Current phacoemulsification techniques can safely manage eyes with senile white cataracts. The increased risk of difficulty with continuous capsulorrhexis in type-I and type-III white cataracts and the substantial nuclear hardness in type-II and mainly type-III white cataracts would suggest that current phacoemulsification techniques might not be as successful in these patients as they are in ordinary earlier cataracts.

Primary vitrectomy with perfluoro-n-octane use in the treatment of pseudophakic retinal detachment with undetected retinal breaks.

PURPOSE: This report describes the results of a prospective trial to evaluate the efficacy of pars plana vitrectomy (PPV) in conjunction with perfluoro-n-octane (PFO) as initial treatment of pseudophakic retinal detachment (RD) with no breaks diagnosed preoperatively. METHODS: Fourteen consecutive eyes presenting with pseudophakic RD in which retinal breaks could not be identified preoperatively underwent primary PPV, internal microsurgical identification of the retinal breaks with endoillumination and noncontact wide angle viewing system, PFO retinal reattachment, transscleral cryopexy or endolaser treatment of breaks, PFO-air exchange, and final injection of 20% sulfur hexafluoride. In five eyes, a scleral buckle was also used. Mean follow-up period was 18 months. RESULTS: In 13 of the 14 eyes in which no breaks had been identified preoperatively, breaks were diagnosed during surgery. Perfluoro-n-octane retinal attachment facilitated accurate microscopic treatment of retinal breaks. The retina was reattached with a single operation in all eyes. Eleven eyes had final visual acuity of 20/60 or better. Complications were minimal. CONCLUSIONS: Pars plana vitrectomy in conjunction with PFO expression of subretinal fluid is effective in the initial treatment of pseudophakic RD with no preoperative diagnosis of retinal breaks.

Macular hole formation in diabetic retinopathy: the role of coexisting macular edema.

The aim of this study was to characterise different etiologies for the development of macular holes in diabetic retinopathy. We examined 8 eyes of 8 patients with known diabetic retinopathy who had developed a macular hole. These were classified as follows: related to macular edema (4 eyes), non-related to macular edema (2 eyes), intraoperative (1 eye) or postoperative (1 eye) after pars plana vitrectomy for proliferative diabetic retinopathy. In three patients the macular holes were treated with pars plana vitrectomy and fluid air exchange. In diabetic eyes with macular edema, macular holes may develop because of intraretinal exudation combined with increased vitreomacular attachments and tractions. The mechanism of macular hole formation in diabetic eyes without macular edema probably results from the same increased tangential vitreous traction which is seen in idiopathic age-related macular holes. Iatrogenically induced macular holes during pars plana vitrectomy for proliferative diabetic retinopathy may be also due to intraoperative vitreoretinal tugging. Finally, macular holes developing after vitrectomy may have an etiology not related to vitreous tractions or attachments.

The risk of optic nerve injury in retrobulbar anesthesia: a comparative study of 35 and 40 mm retrobulbar needles in 12 cadavers.

PURPOSE: This study was designed to demonstrate the increased risk of optic nerve injury by the 40 mm needle when fully inserted into the orbit. METHODS: Retrobulbar anesthesia needles 35 and 40 mm long were inserted into the orbits of 12 well-embalmed cadavers, as for typical retrobulbar anesthesia. The needle was seen directly through a fenestration of the orbital roof and by dissection of the orbital structures overlying the optic nerve. RESULTS: In all orbits the 40 mm needle reached and in seven cases significantly pushed against the optic nerve and could obviously penetrate its sheaths. The 35 mm needle could just slightly touch the outer optic nerve sheath only in two cases. CONCLUSIONS: We conclude that the 40 mm retrobulbar needle should not be fully inserted into the orbit and the 35 mm retrobulbar needle must be used with caution.

Experimental ocular surgery with a high-repetition-rate erbium:YAG laser.

PURPOSE: To evaluate the performance in ocular surgery and the ocular tissue interactions resulting from increasing the maximum repetition rate of a pulsed-mode erbium:YAG laser system from 30 to 200 pulses per second. METHODS: An erbium:YAG laser was used that emitted at 2.94 microm with an output graduated from 0.2 mJ to 25 mJ and a repetition rate from 2 Hz to 200 Hz and that was equipped with a flexible optical fiber attached to various interchangeable 20-gauge endoprobes to perform ocular surgery in enucleated pig eyes. The specific maneuvers were performed in close contact in nontransmitting aqueous media and included inner retinal ablation, retinotomy, lens capsulotomy, lens ablation, iridotomy, and iridectomy. Selected tissue specimens were examined by light microscopy. RESULTS: Increasing the repetition rate to the 200-Hz range significantly improved the smoothness, continuity, and speed of all surgical maneuvers. Compared with the 30-Hz rate, substantially lower energies per pulse were efficient with the 200-Hz rate. The "sticking effect" between the tip of the probe and the target tissue at low-repetition rates, which resulted in discontinuation of the surgical maneuver, particularly during lens surgery, was eliminated with the use of high-repetition rates. Use of high-repetition rates produced a zone of residual thermal damage less than 30 microm in all ocular tissues. The histologic findings of tissue interactions were comparable to those obtained in published studies in which the same wavelength and low hertz rates were used. CONCLUSIONS: The high-repetition-rate erbium:YAG laser technology described is advantageous, compared with low-repetition-rate erbium:YAG lasers, and is applicable in a variety of ocular surgical procedures. Innovations in endoprobe design and further study will determine its role in contemporary ocular surgery.

Orbital depth measurements of human skulls in relation to retrobulbar anesthesia.

To investigate the orbital depth in human skulls in relation to retrobulbar anesthesia, we measured the distance between the lateral margin of the optic foramen and the border of the medium and outer third of the inferior orbital rim (retrobulbar needle pathway) in 50 skulls (25 males and 25 females). This distance varied from 4.4 to 5.7 cm in males (mean 5.024, SD 0.272) and from 4.5 to 5.5 cm in females (mean 4.9, SD 0.204). There was no real difference between males and females (p>0.05). For the total of 50 skulls the mean distance was 4.962 cm (SD 0.246). Shallow and deep orbits exist in both males and females but individuals with shallow orbits are obviously more susceptible to optic nerve injury by the retrobulbar needle.