A novel index for predicting macular thickening after cataract surgery.

PURPOSE: In this study, we tried to investigate weather or not the preoperative anterior chamber depth, the lens thickness (LT) and the relation between these variables by the ratio (K) of the distance from the corneal peak to the posterior side of the lens (A) (K = A/LT) could be predictive for a surgically induced foveal thickening following uneventful cataract surgery in normal, emmetropic eyes. PATIENTS AND METHODS: A total amount of 45 eyes, 25 females and 20 males, were enrolled in this study and underwent uncomplicated phacoemulsification under topical anesthesia. A complete ophthalmological examination was performed preoperatively, including refraction, best corrected visual acuity, slit-lamp examination, biometry and optical coherence tomography of both eyes. These examinations, with the exception of the biometric examination, were repeated one day, one week and four weeks after surgery. RESULTS: The K ratio was positively correlated with the macular thickness changes after cataract surgery. The Pearson correlation analysis of K ratio and foveal thickness changes was 0.792 (y = 36.457x - 52.558, R2 = 0.6266). CONCLUSIONS: A novel ratio that incorporates preoperative ocular parameters has been described. It could be easily measured in a clinical setting, and appears to be strongly predictive for macular thickening following cataract surgery. Of course, further studies enrolling a larger amount of patients are necessary in order to confirm these preliminary data.

Citicoline oral solution in glaucoma: is there a role in slowing disease progression?

PURPOSE: To assess the effect of citicoline on visual field rates of progression in patients with progressing glaucoma. PATIENTS AND METHODS: Forty-one patients with a diagnosis of progressing glaucoma received citicoline in oral solution for 2 years. Included were patients with a disease progression of at least -1 dB/year (at MD, mean deviation) for at least 3 years before entering the study despite controlled intraocular pressure (IOP). Patients were followed with 4 visual field examinations per year for 2 years. RESULTS: At baseline, the mean rate of progression was -1.1 (±0.7) dB/year despite the fact that the IOP had been below 18 mm Hg for at least 3 years. At study inclusion, the mean IOP was 15.5 (±2.6) mm Hg and the mean MD was -9.2 (±6.7) dB in the worst eye. Starting from the first cycle of treatment with citicoline, the mean rate of progression significantly changed to -0.15 (±0.3) dB/year at the end of the study (p = 0.01). CONCLUSIONS: This study seems to indicate that supplementation with citicoline might significantly slow down glaucomatous rates of progression.

Aqueous humor oxidative stress proteomic levels in primary open angle glaucoma.

The purpose of this work was to investigate the expression of glutamine synthase (GS), nitric oxide synthase (NOS) superoxide dismutase (SOD) and glutathione transferase (GST) in the aqueous humor of patients with primary open angle glaucoma and controls. Aqueous humor proteome was analyzed by antibody microarray. The expression of tested proteins was detected by protein Cy3/Cy5 labeling, column purification and hybridization on antibody-spotted glass microarray. Fluorescent signals were detected by fluorescence laser scanning. Aqueous humor levels of SOD as well as of GST were significantly lower (2.0- and 2.2-fold, p < 0.01) among patients than controls; both NOS and GS expression were significantly higher (2.2- and 2.6 fold, p < 0.01) among patients than controls. Our data showed substantial differences of GS, NOS2, SOD and GST aqueous humor levels between glaucomatous patients and controls as measured by antibody microarray technology. The overproduction of NO through inducible NOS can form toxic products and change the metabolic conditions of the TM. The GS over-expression might be related to neuronal injury or to the potential role of glutamate as a modulator in the ciliary body signaling. The reduced expression of the antioxidant enzymes SOD and GST could aggravate the unbalance between both oxygen- and nitrogen-derived free radicals production and detoxification. Based on our results, GS, NOS2, SOD and GST as measured by antibody microarray technology may be useful oxidative markers in aqueous humor of glaucomatous patients.

Efficacy of the fixed combinations of bimatoprost or latanoprost plus timolol in patients uncontrolled with prostaglandin monotherapy: a multicenter, randomized, investigator-masked, clinical study.

PURPOSE: To compare the efficacy and tolerability of a once-daily evening dose of bimatoprost/timolol fixed combination (BTFC) with that of a once-daily evening dose of latanoprost/timolol fixed combination (LTFC) in patients not controlled with prostaglandins analogues monotherapy. METHODS: A total of 82 patients on prostaglandin analogues monotherapy were enrolled in this prospective, multicenter, investigator masked, clinical study and were randomized to either BTFC (n=47) or LTFC (n=35) topical therapy once at night for 12 weeks. The primary endpoint of the study was to compare the mean daily intraocular pressure (IOP) reduction from baseline between the two treatment arms. Secondary endpoints included the mean daily IOP at 1 and 3 months compared to baseline and the percentage of patients showing a mean IOP reduction from baseline greater than or equal to 15% or 20%. RESULTS: Mean IOP at baseline was 22.7+/-2.0 and 22.1+/-2.6 mmHg in the BTFC and LTFC groups, respectively (p=0.23). Both treatments were effective in reducing the IOP from baseline. The mean IOP reduction was significantly greater in the BTFC group than in the LTFC group (-21.4% vs -13.7%, p<0.001). A higher percentage of patients in the BTFC group showed a mean IOP reduction from baseline >or=15% (72.3% vs 40.0%) and >or=20% (61.7% vs 17.1%) compared to patients in the LTFC group. CONCLUSIONS: Both BTFC and LTFC were more effective versus the monotherapy with prostaglandin analogues. BTFC demonstrated higher performance than LTFC in terms of relative IOP reduction.

The role of Humphrey Matrix testing in the early diagnosis of retinopathy in type 1 diabetes.

AIM: The aim of the study was to investigate the role of Humphrey Matrix threshold testing in the detection of early functional retinal impairment in subjects with type 1 diabetes mellitus (DM1) without any signs of retinal vasculopathy, and to investigate the relationship between both functional and structural retinal parameters and metabolic control. METHODS: Thirty eyes of 30 subjects with DM1, with no sign of retinal vasculopathy, and 30 eyes of 30 age- and sex-matched healthy subjects were enrolled in this cross-sectional clinical study. Functional testing included Humphrey Matrix perimetry and white-on-white Humphrey visual field perimetry (HFA), while retinal nerve fibre layer (RNFL) thickness was measured by scanning laser polarimetry with variable corneal birefringence compensator (GDx VCC). RESULTS: Matrix mean deviation (MD) was found to be significantly reduced in subjects with DM1 compared with controls (-1.10 (SD 2.98; 95% CI -2.21 to 0.01) vs 1.37 (SD 2.11; 95% CI 0.58 to 2.16), p = 0.0005). HFA MD and pattern standard deviation (PSD) were significantly worse in subjects with DM1 compared with controls (p = 0.010 and p = 0.013 respectively). Among structural parameters, average peripapillary RNFL thickness was reduced in DM1 subjects (p = 0.006). Matrix MD and HFA MD and PSD, and average peripapillary and superior RNFL, were significantly reduced in subjects with DM1 with HbA(1c) > or = 7% compared with controls. CONCLUSIONS: Functional and structural retinal testing by Humphrey Matrix and GDx VCC could be useful for the identification of early retinal impairment in people with DM1 with no sign of retinal vasculopathy.

Influence of endogenous and exogenous sex hormones on plasma brain-derived neurotrophic factor.

BACKGROUND: Brain-derived neurotrophic factor (BDNF) is a mediator of neuronal plasticity and influences learning, memory and cognitive behaviour. The aim of this study is to assess plasma BDNF variations according to hormonal status. METHODS: A total of 60 subjects were included: 20 fertile ovulatory women, 15 amenorrhoeic women and 25 postmenopausal women. Blood samples were collected after overnight fasting. For 5 out of the 20 fertile women, samples were collected every 2 days throughout the whole menstrual cycle. Following basal evaluation, 10 out of 25 postmenopausal women were administered a hormone replacement therapy (HRT) and reevaluated after 6 months of treatment. Plasma BDNF concentrations were measured by enzyme-linked immunosorbent assay. In fertile women, estradiol (E(2)), progesterone and gonadotrophins were also assessed. RESULTS: In fertile women, luteal phase levels of plasma BDNF were significantly higher than follicular phase levels (P < 0.001). BDNF increased from early follicular phase up to Day 14 of the cycle, reaching a pre-ovulatory peak, similar to E(2). A second rise took place during mid-luteal phase, with a peak on Day 24. Amenorrhoeic subjects, as well as postmenopausal women, showed significantly lower plasma BDNF levels compared with fertile females (P < 0.001). BDNF was positively correlated with E(2) and progesterone and negatively correlated with menopausal age. HRT restored BDNF levels to those present in fertile women during the follicular phase. CONCLUSIONS: Plasma BDNF levels are influenced by hormonal status. Modifications in BDNF circulating levels during the menstrual cycle suggest a potential role for gonadal sex hormones (E(2) and progesterone) in regulating neurotrophin expression.

Progesterone and progestins: effects on brain, allopregnanolone and beta-endorphin.

The increased use of hormonal therapies over the last years has led to improve the knowledge of pharmacological, biochemical and metabolic properties of several progestins and their effects in target tissues, such as the central nervous system. Progesterone and synthetic progestational agents are able to modulate the synthesis and release of several neurotransmitters and neuropeptides in response to specific physiological and pathological stimuli. While these actions may relay on differential activation of progesterone receptor or recruitment of intracellular pathways, some of the differences found between synthetic progestins may depend on the specific conversion to neuroactive steroids, such as the 3-alpha, 5-alpha reduced metabolite, allopregnanolone. This is a potent endogenous steroid that rapidly affects the excitability of neurons and glia cells through direct modulation of the GABA-A receptors activity exerting hypnotic/sedative, anxiolytic, anaesthetic and anticonvulsive properties. Estrogens increase the CNS and serum levels of allopregnanolone and the addition of certain but not all synthetic progestins determines a further increase in allopregnanolone levels, suggesting that the metabolism into this reduced product is related to the chemical structure of progestin molecule used. In addition, depending on specific progestin molecule used, different interaction are found with the estradiol-induced beta-endorphin synthesis and release, showing that diverse progestins have specific and divergent actions on the opiatergic system. These results highlight the concept that natural and synthetic progesterone receptor agonists may systematically induce different biological actions in CNS. This may have far-reaching implications for the clinical effects and related indications of each compound.

Corneal birefringence changes after laser assisted in situ keratomileusis and their influence on retinal nerve fibre layer thickness measurement by means of scanning laser polarimetry.

AIM: To evaluate changes in corneal polarisation properties and their influence on peripapillary retinal nerve fibre layer (RNFL) thickness measurements after laser assisted in situ keratomileusis (LASIK) by means of scanning laser polarimetry (SLP) with variable corneal polarisation compensator (VCC) in normal white subjects. METHODS: SLP was performed by means of GDx VCC on 32 eyes of 32 normal subjects who underwent LASIK for ametropia correction. Corneal polarisation axis and magnitude and RNFL thickness were measured before and 8 days after LASIK. RNFL thickness data and corneal polarimetric data of one randomly selected eye per subject were analysed by the Wilcoxon signed ranks test. Correlations between corneal ablation depth, corneal polarimetric changes, and RNFL thickness changes were investigated using Spearman's rho test. RESULTS: The corneal polarisation axis significantly shifted from 15.1 degrees (17.0 degrees ) to 6.9 degrees (12.9 degrees ) (p = 0.00006) after LASIK and this change showed a strong correlation with corneal ablation depth (rho = -0.7, p = 0.00002). Among GDx parameters, TSNIT, SUP, and SD showed significant changes after LASIK and for SUP and SD these changes were well correlated with the shift in corneal polarisation axis (rho = 0.54, p = 0.03 and rho = 0.45, p = 0.01, respectively). SUP and SD changes were neutralised after compensating for corneal polarimetric changes but not TSNIT changes. NFI, a discriminating parameter, was found to be affected after LASIK only after compensating for corneal polarimetric changes. CONCLUSIONS: LASIK induces a shift in corneal polarisation axis which is responsible for inaccuracies in RNFL thickness measurements. A customised compensation for corneal polarimetric changes after LASIK allows normalisation of some of the thickness parameters except for TSNIT and NFI.

Pilot study to evaluate the efficacy and safety of pneumatic trabeculoplasty in glaucoma and ocular hypertension.

PURPOSE: Following laser-assisted in situ keratomileusis (LASIK), intraocular pressure (IOP) is measurably lower in a significant number of cases. It has been proposed that the decrease in IOP may be a real event. Prior trials have evaluated pneumatic trabeculoplasty (PNT) in combination with concomitant glaucoma medications. The aim of this study was to determine the efficacy and the safety of PNT alone to lower IOP in patients with primary open angle glaucoma (POAG) or ocular hypertension (OH). METHODS AND RESULTS: A total of 37 subjects with POAG or OH were enrolled in a prospective, open-label, fellow-eye, multicenter trial to determine the IOP lowering effects of PNT. All subjects underwent ophthalmologic examinations and IOP measurements and were washed out from all glaucoma medications prior to the start of the study. The trial was intrapatient controlled for the first 30 days, with one eye receiving PNT at days 0 and 7 and the fellow eye serving as the control. The second eye was treated with PNT at day 30. The patients were followed for 120 days, with the first eye receiving an additional PNT treatment at days 90 and 97. Two analyses-an intent to treat analysis in which the last IOP measurement for patients dropped from the study was carried forward and an analysis including only those patients who completed the trial-were performed. Of the 37 patients enrolled, 27 (73%) completed the study. For the intent to treat analysis the baseline mean IOP was 24.7+/-1.9 mmHg for eye 1 and 23.6+/-2.3 mmHg for eye 2 and the difference was statistically significant (p<0.05). Using this analysis the differences between eye 1 mean IOP at days 1, 7, 14, and 60 and the baseline mean IOP were statistically significant (p<0.05). The differences between eye 2 mean IOP and the baseline mean IOP were statistically significant (p<0.05) at all time points except day 14 and day 30. The greater mean IOP reductions from the baseline mean IOP for eye 1 were at study day 1 (-16,1%), day 14 (-9%), and day 60 (-8.9%). For eye 2 they were at day 60 (-8.7%) and at day 120 (-9.1%). For the analysis that included only those subjects who completed the trial the decrease in eye 1 mean IOP from baseline was statistically significant (p<0.05) at all time points. The decrease in eye 2 mean IOP from baseline was statistically significant at all time points except day 30. Using this analysis the greater mean IOP reductions from the baseline mean IOP for eye 1 were at study day 1 (-19%), day 14 (-15.7%), day 37 (-16.3%), day 60 (-20.0%), day 90 (-18.1%), day 97 (-16.8%), and day 120 (-15.8%). For eye 2 greater mean IOP reductions from baseline mean IOP were seen on day 37 (-13.0%), day 60 (-16.7%), day 90 (-15.5%), day 97 (-14.5%), and day 120 (-7.2%). No statistically significant differences were found in mean IOP reduction between the two eyes treated. A total of 34 patients (92%) showed adverse effects: conjunctival hyperemia in 26 (70.3%) and conjunctival hemorrhage in 14 (37.8%). CONCLUSIONS: This pilot study of PNT showed a potentially good IOP lowering effect on glaucoma and hypertensive patients. Additional studies would help to better define the types of patients who respond to PNT and to identify risk factors that may lead to treatment failure.

Pulsatile ocular blood flow during pregnancy.

PURPOSE: To study pulsatile ocular blood flow (POBF) throughout pregnancy. METHODS: We enrolled twenty-seven healthy women in the first trimester of gestation, only ten of which were followed through the second trimester, and fourteen non pregnant healthy women. In each subject we measured POBF with the POBF pneumotonometer (OBF Ltd. UK), IOP, blood pressure (BP) and heart rate (HR). An unpaired Student t-test was used to compare pregnant women with non-pregnant women, and a two-tailed paired Student t-test was used to compare the same women in the first and second trimester of pregnancy. p <0.05 is considered statistically significant. RESULTS: Results are presented as means +/- SD. In the first trimester of pregnancy the age was 32 +/- 6, POBF 1516.4 +/- 382 ml/min, IOP 13 +/- 3 mmHg, BP 92 +/- 6 mmHg, and HR 86 +/- 14 beats/min. In the second trimester POBF was 1629.11 +/- 352.4 ml/min, intraocular pressure (IOP) 12 +/- 3 mmHg, BP 96 +/- 3 mmHg, and HR 93 +/- 10 beats/min. In the control group the age was 27 +/- 9, POBF 972.23 +/- 329.3 ml/min, BP 88 +/- 4.3 mmHg, and HR 80 +/- 14 beats/min. POBF increases during the first trimester (p = 0.00008). In the second trimester POBF was higher compared to the first trimester (p = 0.0008). Non significant differences were observed for the other parameters. CONCLUSIONS: The POBF increases throughout gestation. During pregnancy there is an increase in estrogen which induces endothelial-dependent vasodilatation in several tissues. The estrogen changes may influence POBF.

Correlation between optical coherence tomography, pattern electroretinogram, and visual evoked potentials in open-angle glaucoma patients.

OBJECTIVE: [corrected] To correlate the nerve fiber layer (NFL) thickness and the visual function evaluated by electrophysiologic retinal and cortical responses assessed in open-angle glaucoma (OAG) eyes. DESIGN: Prospective case-control study. PARTICIPANTS: Thirty glaucoma patients (mean age, 47.1 +/- 7.15 years; refractive error range, +/- 2 spherical equivalent) with a mean deviation of computerized static perimetry (24/2 Humphrey, Dublin, CA) from -5 to -28 dB and intraocular pressure less than 21 mmHg on pharmacologic treatment and 14 age-matched control participants. METHODS: Nerve fiber layer thickness was measured by optical coherence tomography. Retinal and visual pathway function was assessed by simultaneously recording pattern electroretinograms (PERGs) and visual evoked potentials (VEPs) using high-contrast (80%) checkerboard stimuli (the single check edges subtend 15 minutes of the visual arc) reversed at the rate of two reversals per second. Linear regression analyses were adopted to establish the correlation between NFL thickness and PERG and VEP parameters. MAIN OUTCOME MEASURES: Nerve fiber layer thickness measurements in each quadrant (superior, inferior, nasal, and temporal) were taken and then averaged (12 values averaged) and identified as NFL overall, whereas the data obtained in the temporal quadrant only (three values averaged) were identified as NFL temporal. PERG P50 implicit time and P50-N95 amplitude and VEP P100 implicit time and N75-P100 amplitude were also measured. RESULTS: In OAG eyes, we found a significant (P < 0.01) reduction in NFL thickness in both NFL overall and NFL temporal evaluations with respect to the values observed in control eyes. PERG and VEP parameters showed a significant (P < 0.01) delay in implicit time and a reduction in peak-to-peak amplitude. In OAG eyes, the NFL overall and NFL temporal values were significantly correlated (P < 0.01) with the PERG P50 implicit time and P50-95 peak-to-peak amplitude. No correlations (P > 0.01) between NFL values and VEP parameters were found. CONCLUSIONS: There is a correlation between PERG changes and NFL thickness, but there is no correlation between VEP changes and NFL thickness in patients affected by OAG.

Comparative acute effects of brimonidine 0.2% versus dorzolamide 2% combined with beta-blockers in glaucoma.

PURPOSE: To assess the acute intraocular hypotensive efficacy of brimonidine tartrate 0.2% (a highly selective alpha2-adrenergic agonist) compared with dorzolamide 2% (a topical carbonic anhydrase inhibitor) as adjunct therapy to topical beta-blockers in patients with primary open-angle glaucoma. METHODS: A randomized cross-over masked study was performed. We enrolled one eye of each of 28 patients who were on different beta-blocker therapy. We measured the intraocular pressure (IOP) 2 h after the beta-blocker instillation; we then randomly administered one of the two drugs and we compiled an IOP diurnal curve. One month later we repeated the same procedures with the second drug. Unpaired Mann-Whitney U-test was used to compare decreases in IOP between the two drugs (P<0.05). RESULTS: Both brimonidine 0.2% and dorzolamide 2% have good ocular hypotensive efficacy, significantly lowering IOP when compared to beta-blocker therapy alone, for the whole diurnal curve. Maximum mean percent IOP decrease from baseline was 22.0+/-15.7% (4.0+/-2.9 mmHg) for dorzolamide 2% 6 h after instillation and 35.5+/-16.4% (7.0+/-4.1 mmHg) for brimonidine 0.2% 8 h after administration of the drug. When we compared the two treatments, brimonidine 0.2% showed a higher hypotensive effect than 2% dorzolamide after 4 h (28.4+/-16.8% vs 17.6 +/-9.3%; P=0.04) and 8 h (35.5+/-16.4% vs 21.6 +/-10.8%; P=0.04). CONCLUSION: This study indicates that 0.2% brimonidine acutely associated with beta-blockers is an interesting new combination treatment useful in the management of glaucoma.

Do sex and hormonal status influence choroidal circulation?

AIMS: To investigate the relation between pulse amplitude (PA), pulsatile ocular blood flow (POBF), and sex and hormonal status. METHODS: Measurements of POBF and PA were obtained by ocular blood flow tonography in 76 healthy subjects: 32 males and 44 females (age range 17-77 years). Females were divided into two age groups: group 1 (premenopausal) 17-42 years, and group 2 (post-menopausal) 55 years old and over. Two groups of age matched males served as controls. RESULTS: Premenopausal females demonstrated a significantly higher rate of POBF and PA than age matched males and post-menopausal females. CONCLUSION: Sex and hormonal status were shown to influence choroidal circulation.

Visual function correlates with nerve fiber layer thickness in eyes affected by ocular hypertension.

PURPOSE: To test whether the high variability observed when measuring pattern electroretinogram (PERG), visual evoked potentials (VEP), and spatial contrast sensitivity (SCS) in eyes with ocular hypertension is associated with variation in nerve fiber layer thickness, as measured by optical coherence tomography (OCT). METHODS: The study involved 32 untreated eyes (32 patients; age range, 29-64 years) showing a normal whiteon-white 24/2 Humphrey (San Leandro, CA) perimetry, IOP between 23 and 28 mm Hg, best corrected acuity of 20/20 or better, and none of the following papillary signs on conventional color stereo slides: rim notch(es), peripapillary splinter hemorrhages, or increased vertical-to-horizontal cup-to-disc ratio. On recruitment, each eye underwent SCS testing, OCT, PERG, and VEP recordings. Linear regression (Pearson's test) or Spearman's rank regression was adopted for the analysis of the data. RESULTS: The 95% confidence limits of the electrophysiological data were: PERG P50 latency, 59.3 to 63 msec; PERG P50 to N95 amplitude, 0.74 to 1.15 cmV; VEP P100 latency, 113 to 118 msec; VEP N75 to P100 amplitude, 3.81 to 4.90 micromV. The 360 degrees nerve fiber layer thickness overall (NFLO) ranged between 113 and 169 microm (145+/-16 microm; mean+/-SD) and significantly correlated with PERG P50 to N95 amplitude (r: 0.518; P = 0.002), PERG P50 latency (r: -0.470; P = 0.007), VEP N75 to P100 amplitude (r: 0.460; P = 0.008), VEP P100 latency (r = -0.422; P = 0.016) and SCS at 3 cyc/deg (r: -0.358; P = 0.044). CONCLUSIONS: The variability of PERG, VEP, and SCS testing observed in eyes with ocular hypertension is associated with differences in NFL thickness (the thinner the layer, the worse the visual function).

ENVIRONMENTAL AUDITING: The Fish Fauna of the Doubs River Prior to Completion of the Rhine-Rhone Connection

/ The part of the Doubs River between Montbeliard and Dole (France), i.e., downstream from the confluence with the Allan River, will be affected by the Rhine- Rhone connection project. In order to improve the understanding of the Doubs ichthyofauna, aquatic environments of the Doubs were sampled by electrofishing. Fish diversity and the presence of some rheophilic species demonstrated the good ecological quality of some stretches of the Doubs. This quality was due to alternating areas with very diversified aquatic environments (riffles, islands and side-arms, backwaters) and a considerable range of flow velocities. The differences in the structure of the fish communities of the different types of aquatic environments were more qualitative (fish species) than quantitative (number of species and number of fish). However, the mean number of fish was statistically lower in the canals (Freycinet canal and channelized part of the Allan River) than in the main course and in the backwaters. The natural parts of the Doubs (unnavigable reaches) showed the most diversified environmental structure and had the most rheophilic fish communities. Thus, the rheophilic species were well represented, but they proved also the most vulnerable to river regulation. However, the most abundant fishes throughout the Doubs River were generalists with no special requirements for food sources or spawning substrate.KEY WORDS: Fish communities; Regulation; Restoration; Floodplain; Large ship canal; Doubs River

Comparative effects of intraocular pressure between systemic and topical carbonic anhydrase inhibitors: a clinical masked, cross-over study.

The aims of the following study were to compare the efficacy of Dorzolamide 1% eye drops with systemic Acetazolamide on the ocular pressure diurnal curve in patients with maximal medical therapy. Three ocular pressure curve were performed in glaucomatous patients, already receiving maximal medical therapy. After a baseline curve, patients were pretreated either with Dorzolamide 1% eye drops or 250 mg Acetazolamide tablets in a double-blind cross-over study. Dorzolamide 1% eye drops and 250 mg Acetazolamide tablets significantly reduced intraocular pressure (IOP) at 2 and 4 h after pretreatment. Both treatments caused a significantly additional decrease of IOP despite maximal medical therapy. Dorzolamide 1% eye drops is as effective as Acetazolamide tablets in reducing the IOP curve. Topical carbonic anhydrase inhibitors may represent an additional and safer treatment for those patients with uncontrolled medical glaucoma.