The Effect of Yoga on Intraocular Pressure Using the "iCare HOME2" Tonometer.

BACKGROUND: Various yoga positions may have an unfavorable impact on intraocular pressure (IOP) and may therefore be seen as a potential risk factor for the progression of glaucoma. The new "iCare HOME2" is a handheld self-tonometer for IOP measurements outside clinical settings. This is the first study to evaluate the immediate effect of common yoga postures on the IOP of healthy and glaucomatous eyes using the "iCare HOME2" self-tonometer and to compare the time of IOP recovery in both groups. METHODS: This is a single-center, prospective, observational study including 25 healthy and 25 glaucoma patients performing the following yoga positions: "legs up" (Viparita Karani), "bend over" (Uttanasana), "plough pose" (Halasana), and the "down face dog" (Adho Mukha Svanasana) for 90 s each, with a 2-min break in between. IOP was measured with the "iCare HOME2" before, during, and after each position. RESULTS: IOP significantly increased in all eyes in all positions (p < 0.05), showing no statistically significant difference between healthy or glaucomatous eyes (p > 0.05). The mean rise in IOP in healthy subjects was 1.6 mmHg (SD 1.42; p = 0.037), 14.4 mmHg (SD 4.48; p < 0.001), 7.5 mmHg (SD 4.21; p < 0.001), and 16.5 mmHg (SD 3.71; p < 0.001), whereas in glaucoma patients, IOP rose by 2.8 mmHg (SD 2.8; p = 0.017), 11.6 mmHg (SD 3.86; p < 0.001), 6.0 mmHg (SD 2.24; p < 0.001), and 15.1 mmHg (SD 4.44; p < 0.001) during the above listed yoga positions, repsectively. The highest increase in IOP was seen in the down face position, reaching mean IOP values above 31 mmHg in both study groups. IOP elevation was observed immediately after assuming the yoga position, with no significant change during the following 90 s of holding each pose (p > 0.05). All IOP values returned to baseline level in all individuals, with no significant difference between healthy and glaucoma participants. CONCLUSION: Our data show that common yoga positions can lead to an acute IOP elevation of up to 31 mmHg in healthy as well as glaucoma eyes, with higher IOP values during head-down positions. Given that IOP peaks are a major risk factor for glaucomatous optic neuropathy, we generally advise glaucoma patients to carefully choose their yoga exercises. If and to what extent practicing yoga leads to glaucoma progression, however, remains unclear and warrants further research.

Severe Optic Disc Cupping Following the Methanol Toxicity in a 20-Year-old Man: A Case Report.

In April 2018, a 20-year-old man with a history of methanol intoxication from an alcoholic drink two years ago, when he was 18 years old, was referred to Nikookari Eye Hospital in Tabriz, Iran. He was admitted to emergency service and underwent eight hours of hemodialysis at the time of poisoning. His past medical history was negative, and he did not take any medication after discharge. The patient had a driving license and never experienced any visual problems before. At presentation, his visual acuity was 160/200 in both eyes with the main complaint of visual field deterioration. Other neurologic exams and brain magnetic resonance imaging (MRI) were reported normal by a neurologist. Optic disc cupping was near total in both eyes with a very narrow remaining rim. Optic disc cupping was very similar to glaucomatous cupping. Intraocular pressure was checked several times via Goldmann tonometry and was 13 mmHg. There was no history of refractive surgery leading to thin cornea. Based on this case, methanol poisoning can mimic glaucomatous optic disc cupping. This is the first case report of methanol toxicity-related optic disc cupping from Iran.

Acupuncture treatment of glaucoma based on radar plots: A protocol for an overview of systematic reviews.

BACKGROUND: Glaucoma is the second most blinding eye disease in the world. Currently, lowering the intraocular pressure through various methods is the main treatment of glaucoma. Acupuncture has been effectively and safely used in the treatment of glaucoma. However, the evidence for the efficacy of acupuncture in the treatment of glaucoma is controversial, leading to inconsistent findings from systematic evaluations at abroad and home. Therefore, this protocol aims to provide a multivariate evaluation on the quality of evidences from current systematic reviews (SRs) and/or meta-analyzes (MAs) of acupuncture in the treatment of glaucoma, and literature quality, thus providing an intuitive and reliable evidence synthesis and basis for clinical decision making. METHODS: MAs/SRs about the acupuncture treatment of glaucoma will be searched online, including Chinese Biomedical Literature Database (CBM), China Science and Technology Journal Database (VIP), China National Knowledge Infrastructure (CNKI), WanFang Database (WF), Web of Science, Embase, PubMed, and Cochrane Library. Two investigators will independently screen literatures according to inclusion and exclusion criteria and extract data. A multivariate evaluation of the included literature will be performed by depicting radar plots in 6 aspects as follows: Year of publication, study type, SRs assessment through the Assessment of Multiple Systematic Reviews 2 (AMSTAR 2), literature quality assessment through the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA), homogeneity, and publication bias. The Grading of Recommendations Assessment, Development, and Evaluation evidence quality assessment tool will be used to grade and evaluate the quality of outcome indicators of the included literatures. RESULTS: This study will be submitted for publication in a peer-reviewed journal. CONCLUSION: We would like to provide a visual and scientific approach for clinical decision making of acupuncture treatment of glaucoma through a accessible and useful assessment of systematic reviews.

Longitudinal assessment of optic nerve head changes using optical coherence tomography in a primate microbead model of ocular hypertension.

In humans, the longitudinal characterisation of early optic nerve head (ONH) damage in ocular hypertension (OHT) is difficult as patients with glaucoma usually have structural ONH damage at the time of diagnosis. Previous studies assessed glaucomatous ONH cupping by measuring the anterior lamina cribrosa depth (LCD) and minimal rim width (MRW) using optical coherence tomography (OCT). In this study, we induced OHT by repeated intracameral microbead injections in 16 cynomolgus primates (10 unilateral; 6 bilateral) and assessed the structural changes of the ONH longitudinally to observe early changes. Elevated intraocular pressure (IOP) in OHT eyes was maintained for 7 months and serial OCT measurements were performed during this period. The mean IOP was significantly elevated in OHT eyes when compared to baseline and compared to the control eyes. Thinner MRW and deeper LCD values from baseline were observed in OHT eyes with the greatest changes seen between month 1 and month 2 of OHT. Both the mean and maximum IOP values were significant predictors of MRW and LCD changes, although the maximum IOP was a slightly better predictor. We believe that this model could be useful to study IOP-induced early ONH structural damage which is important for understanding glaucoma pathogenesis.

Differential Intraocular Pressure Measurements by Tonometry and Direct Cannulation After Treatment with Soluble Adenylyl Cyclase Inhibitors.

PURPOSE: To validate the increase in intraocular pressure (IOP) caused by soluble adenylyl cyclase (sAC) inhibitors and determine reasons behind variation in IOP measurements performed by tonometry. METHODS: C57BL/6J mice were administered DMSO solubilized sAC inhibitors (KH7 or LRE-1) by intraperitoneal injection. Two hours post-treatment, mice were anesthetized with avertin or ketamine/xylazine/acepromazine (KXA). IOP was measured by a rebound tonometer or direct cannulation of the anterior chamber. Spectral-domain optical coherence tomography was used to measure anterior chamber depth and corneal thickness in live mice. Outflow facility was measured in perfused, enucleated mouse eyes. RESULTS: Compared with DMSO controls, KH7 treatment caused an increased IOP in avertin- and KXA-anesthetized mice when measured by direct cannulation [avertin: 14.4 ± 2.1 mmHg vs. 11.1 ± 1.0 mmHg (P = 0.003); KXA: 14.4 ± 1.0 mmHg vs. 11.3 ± 0.8 mmHg (P < 0.001)] and tonometry [avertin: 10.8 ± 1.4 mmHg vs. 7.4 ± 0.6 mmHg (P < 0.001); KXA: 11.9 ± 0.9 mmHg vs. 10.3 ± 1.7 mmHg (P = 0.283)]. However, treatment with KH7 in nonanesthetized mice showed a significant decrease in IOP measured by tonometry and compared with DMSO-treated animals [13.1 ± 2.6 mmHg vs. 15.6 ± 0.5 mmHg (P = 0.003)]. Both KH7- and DMSO-treated groups anesthetized with avertin showed increased corneal thickness, whereas KH7-treated mice anesthetized with KXA exhibited a shallower anterior chamber compared with untreated mice. KH7 decreased outflow facility by 85.1% in nonanesthetized, enucleated eyes (P < 0.003). CONCLUSIONS: Systemically administered DMSO and anesthesia have significant effects on anterior chamber characteristics, resulting in altered IOP readings measured by tonometry. In the presence of DMSO and anesthesia, tonometry IOP readings should be confirmed with direct cannulation.

Glaucoma.

Glaucoma is a heterogeneous group of diseases characterised by cupping of the optic nerve head and visual-field damage. It is the most frequent cause of irreversible blindness worldwide. Progression usually stops if the intraocular pressure is lowered by 30-50% from baseline. Its worldwide age-standardised prevalence in the population aged 40 years or older is about 3·5%. Chronic forms of glaucoma are painless and symptomatic visual-field defects occur late. Early detection by ophthalmological examination is mandatory. Risk factors for primary open-angle glaucoma-the most common form of glaucoma-include older age, elevated intraocular pressure, sub-Saharan African ethnic origin, positive family history, and high myopia. Older age, hyperopia, and east Asian ethnic origin are the main risk factors for primary angle-closure glaucoma. Glaucoma is diagnosed using ophthalmoscopy, tonometry, and perimetry. Treatment to lower intraocular pressure is based on topical drugs, laser therapy, and surgical intervention if other therapeutic modalities fail to prevent progression.

Relationship between corneal biomechanical properties and optic nerve head changes after deep sclerectomy.

PURPOSE: To evaluate corneal biomechanical properties and optic nerve head (ONH) changes following deep sclerectomy (DS) and the relation to each other. METHODS: Forty-nine eyes with primary open-angle glaucoma that underwent DS were studied. Corneal biomechanical properties were assessed using the Ocular Response Analyzer and the ONH was evaluated by Spectralis optical coherence tomography with enhanced depth imaging technology before surgery and 3 months postoperatively. Changes in corneal hysteresis (CH), corneal resistance factor (CRF), optic nerve cupping, prelaminar tissue thickness, and lamina cribrosa depth and thickness were registered. A correlation matrix and multiple linear regression models were used to determine predictors of ONH changes. RESULTS: At 3 months after surgery, mean corneal compensated intraocular pressure (IOPcc) significantly decreased by 27.9% (p<00.001) and mean Goldmann-correlated IOP (IOPg) decreased by 30.52% (p<00.001). Mean CH increased and CRF decreased by 18.4% and 10.1%, respectively (p<00.001). There was a significant reversal of ONH cupping mainly due to a prelaminar tissue thickening (p<00.001). Significant associations were found between ONH cupping reversal and prelaminar tissue thickening with preoperative IOPcc (p = 0.046), IOPg (p = 0.02), and CRF (p = 0.002) and with changes in IOP, CH, and CRF (p<00.001, p = 0.004, p = 0.018, respectively) after surgery. CONCLUSIONS: Corneal hysteresis increased and CRF decreased significantly 3 months after DS. Corneal resistance factor was the single largest preoperative factor influencing cupping reversal changes. Despite the influence of preoperative variables, postoperative IOP reduction was the only independent factor influencing changes observed in the ONH after surgery.

Measurement of intraocular pressure in healthy unanesthetized inland bearded dragons (Pogona vitticeps).

OBJECTIVE: To evaluate the use of rebound and applanation tonometry for the measurement of intraocular pressure (IOP) and to assess diurnal variations in and the effect of topical anesthesia on the IOP of healthy inland bearded dragons (Pogona vitticeps). ANIMALS: 56 bearded dragons from 4 months to 11 years old. PROCEDURES: For each animal following an initial ophthalmic examination, 3 IOP measurements were obtained on each eye between 9 AM and 10 AM, 1 PM and 2 PM, and 5 PM and 7 PM by use of rebound and applanation tonometry. An additional measurement was obtained by rebound tonometry for each eye in the evening following the application of a topical anesthetic to evaluate changes in the tolerance of the animals to the tonometer. Descriptive data were generated, and the effects of sex, time of day, and topical anesthesia on IOP were evaluated. RESULTS: Bearded dragons did not tolerate applanation tonometry even following topical anesthesia. Median daily IOP as determined by rebound tonometry was 6.16 mm Hg (95% confidence interval, 5.61 to 6.44 mm Hg). The IOP did not differ significantly between the right and left eyes. The IOP was highest in the morning, which indicated that the IOP in this species undergoes diurnal variations. Topical anesthesia did not significantly affect IOP, but it did improve the compliance for all subjects. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that rebound tonometry, but not applanation tonometry, was appropriate for measurement of IOP in bearded dragons. These findings provided preliminary guidelines for IOP measurement and ophthalmic evaluation in bearded dragons.

Prevalence of increased intraocular pressure and optic disk cupping: multicenter glaucoma screening in Israel during the 2009 and 2010 World Glaucoma Weeks.

BACKGROUND: Early detection of glaucoma enables early initiation of treatment. Screening populations at risk is likely to help achieve this goal. OBJECTIVES: To increase public awareness regarding early detection of glaucoma, and estimate the prevalence of increased intraocular pressure (IOP) and optic disk cupping in the screened population. METHODS: A public awareness campaign was carried out in Israel during the 2009 and 2010 World Glaucoma Week, culminating each year in a one-day, free-of-charge screening of individuals in 13 outreach public locations. Screening was performed by 45 ophthalmologists and included a brief medical history, slit-lamp exam with measurement of intraocular pressure (IOP), and evaluation of cup/disk ratio. RESULTS: A total of 2560 individuals were screened; the mean age was 59 +/- 13 years. IOP > or = 21 mmHg was found in 4.8%, and 12.3% had cupping > or = 0.5. IOP > or = 21 mmHg together with cupping > or = 0.5 were present in 1.4% and this rate increased with age: 3.7% of cases in the age group > or = 70 years compared to 1% and 0.6% in the age groups 50-69 and < 50 years, respectively (P < 0.001). Likewise, the prevalence of cupping > or = 0.7 and of IOP > or = 24 mmHg increased significantly with age. The prevalence of IOP > or = 21 mmHg increased in cases with a family history of glaucoma in first-degree relatives (10.5% compared to 3.9%, P < 0.001). The prevalence of IOP > or = 21 mmHg was also increased in diabetic patients (8.3% vs. 4.3% in non-diabetics, P = 0.002). Further ophthalmologic evaluation was recommended to 13% of the screened individuals. CONCLUSIONS: Outreach screening for glaucoma is a valuable tool for detecting glaucoma, pre-perimetric glaucoma, or ocular hypertension in a meaningful number of previously undiagnosed cases. Yet, cost-effectiveness issues should also be considered. The yield of such screening increases with age and seems to be most advantageous in cases with diabetes or a family history of glaucoma.

Intraocular pressure, retrobulbar anaesthesia and digital ocular massage.

OBJECTIVES: To determine the degree of intraocular pressure (IOP) rise following retrobulbar anaesthetic injection as well as the optimal time required for the return of the IOP to the pre-injection level following ocular massage. MATERIALS AND METHODS: Using the Perkins hand-held tonometer, the IOP of consecutive adult patients were measured in the operating room before local anaesthetic (3 ml of 2% xylocaine with or without adrenaline) injection; immediately after injection and every minute following ocular massage for the next 5 minutes. RESULTS: Twenty-three eyes of 17 patients, aged 23-71 years, were studied. The mean (+/- SD) baseline (preinjection) IOP was 16.6 (+/- 6.8) mmHg. Immediately after the injection the IOP rose by 11.8-80% with a mean of 37.3 +/- 16.8% (95% CI: 30.4-44.2). By 3 minutes the IOP had returned to the pre-injection level. After 3 minutes the IOP had become lower than the pre-injection level (p < 0.05) CONCLUSIONS: IOP rise following retrobulbar injection of 3 ml of local anesthetic varies from 11.8-80%. Digital ocular massage lowers the IOP to pre-injection level in 60.2% in 3 minutes; in 5 minutes it lowers the IOP to preinjection level in all eyes and to below pre-injection level 86%.

Evaluation of discomfort of Goldmann tonometry without anaesthetic.

Goldmann applanation tonometry (GAT) is considered the gold standard technique for tonometry. It is a procedure involving administration of topical anaesthetic (a drug which could have several side effects). This prevents a large number of vision care practitioners from using GAT, due to legal restrictions regarding the use of these ophthalmic drugs. The purpose of this study was to establish whether the discomfort experienced during non-anaesthetic Goldmann Applanation Tonometry (NAGAT) would be acceptable to subjects. The intensity of pain inflicted by GAT, NAGAT, Non-Contact Tonometry (NCT) and Schirmer test was assessed on thirty-one subjects enrolled in the study using the Numerical Rating Scale (NRS) to assess pain. The GAT was performed on one eye and the other three procedures were carried out in random order on the fellow eye. Initially, each subject was asked to score their Maximum Pain Without Complaint (MPWC). The MPWC and the Schirmer test were used as references to grade the pain levels. The scores for the five procedures were registered using the NRS (0-10) and compared using a non-parametric statistical analysis (Friedman test and a post-hoc analysis). In addition, IOP results for GAT and NAGAT were also compared using the t-test. The scores obtained on the NRS ranged from 0-4, 0-5, 0-8, 0-7 and 3-8 with a median of 1, 1, 2, 2, and 5, respectively for NCT, GAT, NAGAT, Schirmer and MPWC. A statistically significant difference (p = 0.01) was found between the MPWC and the four clinical tests but no difference was found between the clinical tests. There was no statistically significant difference (p = 0.71) between the IOP results for GAT and NAGAT, 14.0 ± 2.0 mmHg and 13.8 ± 2.0 mmHg (mean ± 1S.D.) respectively. The Goldmann Applanation Tonometry without anaesthetic (NAGAT) can be performed with an acceptable level of discomfort for the majority of subjects and should be performed identically to a traditional GAT, informing the subjects about the possibility of feeling a small discomfort.

Goldmann applanation tonometry over daily disposable contact lens: accuracy and safety of procedure.

PURPOSE: To study accuracy and safety, related to sensation (discomfort) and trauma, when using Goldmann applanation tonometry (GAT) on eyes wearing daily disposable soft contact lenses. METHODS: The intra-ocular pressure (IOP) of 136 normal eyes of 68 subjects was measured by Goldmann tonometer. Measurements were made in one eye with a contact lens (hilafilcon A) without anaesthetic drops and then without the contact lens using one drop of 0.4% oxybuprocaine hydrochloride. Each contact lens used was identical as to back optic zone, back vertex power. Standard Goldmann procedure only was used for the fellow eye of each subject. Subjective sensation (discomfort) responses to both procedures were studied in a subgroup (66 eyes) using a scale of discomfort, from 1 (no sensation) to 5 (highest sensation). Epithelial staining after tonometry was evaluated for this subgroup. RESULTS: No significant differences were found for the IOP with and without contact lens (t<1; p=0.63) for the IOP range studied. There was a good correlation between the two procedures (r=0.81; p<0.05). Lowest sensation was found with tonometry on the anaesthetized cornea; this condition was significantly different from other conditions (p<0.005). No difference was found among the other conditions (contact lens insertion, tonometry on contact lens and application of topical anaesthetic). Corneal epithelial staining following the standard tonometry procedure was significantly higher than following the procedure with a contact lens (p<0.00005). CONCLUSIONS: Measurement of IOP by GAT over a daily disposable soft contact lens is accurate, compared to the standard procedure and within the IOP's normal range studied here. Also using a contact lens results in less trauma whilst discomfort is similar.

Comparative efficacy of pilocarpine, timolol and latanoprost in experimental models of glaucoma.

Intraocular pressure (IOP)-lowering effects of investigational antiglaucoma drugs often need comparison with existing drugs, but detailed data showing comparative efficacy of antiglaucoma drugs with different mechanism of action has not been reported so far. This study was designed to establish baseline information of the IOP-lowering effect of three currently used antiglaucoma drugs in three experimental models in rabbits, so that they act as a benchmark for the efficacy evaluation of the future experimental antiglaucoma drugs. The IOP-lowering effect of single-drop application of pilocarpine, timolol and latanoprost was studied in normotensive, water loading and steroid-induced models of glaucoma in rabbits. The noncontact tonometer was used for the first time to estimate IOP in rabbits. The peak IOP-lowering effect of pilocarpine, timolol and latanoprost in normotensive rabbit eye was 18.23%, 20% and 22.56%, respectively. In water-loading model, the maximum protection against the rise in IOP was shown by latanoprost (40.27%), followed by timolol (31.39%) and pilocarpine (28.91%). In steroid-pretreated rabbit eyes, peak IOP-lowering effects of pilocarpine, timolol and latanoprost were 25.65%, 34.21% and 35.06%, respectively. Therefore, the latanoprost was found to be most effective in all three models followed by timolol and pilocarpine. The results of this study can be used for future preclinical investigations for the assessment of IOP-lowering activity of potential antiglaucoma drugs.

Distribution and determinants of intraocular pressure in a normal pediatric population.

PURPOSE: To examine the intraocular pressure (IOP) of a normal pediatric population under topical anesthesia without sedation and its correlation with other ocular parameters. SUBJECTS AND METHODS: The IOP of 810 eyes of 405 patients with ages ranging from 0 to 12 years was measured using the Perkins applanation tonometer. Cooperative patients also underwent pachymetry, refraction, and biometry measurements. RESULTS: The mean (+/- standard deviation) age was 6.68 (+/- 3.28) years, with a mean (+/- standard deviation) IOP of 12.02 (+/- 3.74) mm Hg. IOP showed an increasing trend with age (correlation coefficieit [r] = 0.49) and tended to approach adult levels by 12 years of age. The IOP correlated directly with refraction (r = 0.69) and pachymetry (r = 0.39) and inversely with axial length (r = -0.1). CONCLUSIONS: The IOP in children is much lower than that in adults. It was noted to increase with age, hyperopia, and corneal thickness and was inversely proportional to axial length.

Noninvasive measurement of rodent intraocular pressure with a rebound tonometer.

PURPOSE: The present study evaluated the applicability of a rebound tonometer in measuring intraocular pressure (IOP) in rats and mice. METHODS: The accuracy of the TonoLab rebound tonometer was determined in cannulated mouse and rat eyes. IOP was manipulated by changing reservoir height, and tonometer pressure readings were recorded by an independent observer. IOP values were recorded in conscious Wistar rats and in four different strains of mice. The effects of anesthesia on IOP were evaluated in two different strains of mice. RESULTS: The IOP readings generated by the rebound tonometer correlated very well with the actual pressure in the eye. In rats, this linear correlation had a slope of 0.96 +/- 0.05 (mean +/- SEM, n = 4) and a Y-intercept of -2.1 +/- 1.2. In mice, the slope was 0.99 +/- 0.05 (n = 3), and the Y-intercept was 0.8 +/- 1.4. Using this method, the resting IOP of conscious male Wistar rats was observed to be 18.4 +/- 0.1 mm Hg (n = 132). In mice, strain differences in IOP were detected. Baseline IOP values in Balb/c, C57-BL/6, CBA, and 11- to 12-month-old DBA/2J mice were 10.6 +/- 0.6, 13.3 +/- 0.3, 16.4 +/- 0.3, and 19.3 +/- 0.4 mm Hg (n = 12), respectively. In separated studies, anesthesia lowered IOP from 14.3 +/- 0.9 to 9.2 +/- 0.5 mm Hg (n = 8) in C57-BL/6 mice, and from 16.6 +/- 0.4 to 9.4 +/- 0.6 mm Hg (n = 10) in CBA mice. CONCLUSIONS: The rebound tonometer was easy to use and accurately measured IOP in rats and mice. This technique, together with advances in genetic and other biological studies in rodents, will be valuable in the further understanding of the etiology and pathology of glaucoma.

Central corneal thickness and intraocular pressure relationship in eyes with and without previous LASIK: comparison of Goldmann applanation tonometer with pneumatonometer.

PURPOSE: To investigate central corneal thickness (CCT) and intraocular pressure (IOP) relationship in eyes with and without previous corneal laser refractive surgery and to compare the estimates of two different tonometers-Goldmann applanation and pneumatonometer. METHODS: The study population included 234 glaucoma suspects who were referred to the glaucoma clinic with cup/disc ratios greater than 0.4, asymmetric cupping, and/or IOP greater than 22 mmHg during routine eye examination. Of those, 84 had previous myopic laser-assisted in situ keratomileusis (LASIK) (Group 1) while 150 of them did not (Group 2). CCT was measured by using optical coherence tomography (OCT) and IOP with both Goldmann applanation tonometer (GAT) and pneumatonometer (PT). In both groups, the difference between IOP estimates of two different tonometers and the relationship between CCT and IOP were analyzed. RESULTS: In eyes with previous LASIK, GAT measured IOP significantly lower than PT (mean difference of 3.8+/-1.9 mmHg, p<0.0001). In eyes with virgin corneas, IOP estimates of GAT or PT were not different from each other (19.9+/-2.8 versus 19.9+/-2.2 mmHg, respectively, p=0.81). In both groups, there was a significant positive correlation between CCT and IOP estimates of GAT(R=0.29, p=0.007 in eyes with LASIK and R=0.38, p<0.0001 in those without), while no similar relationship was present between CCT with those of PT (R=0.03, p=0.76 in eyes with LASIK and R=0.03, p=0.69 in those without). CONCLUSIONS: In eyes with previous LASIK, GAT measured IOP significantly lower than PT. Because IOP estimates of PT were found to be independent from CCT in all of the study eyes, this device was considered to be a more reliable method of IOP estimation than GAT in eyes with and without previous LASIK.

Influencia de la anestesia tópica en los valores tonométricos de la presión intraocular / Influence of the topic anaesthesic in tonometric values of the intraocular pressure

Objetivos: 1. Comparar valores tonométricos (PIO) promedio antes y después del uso de proparacaína y oxibuprocaína, respectivamente. 2. Demostrar y establecer variación estadísticamente significativa en las tomas con y sin anestésico y comparar un anestésico con el otro. Métodos: Diseños observacional prospectivo. Población y muestra: De un total de 400 ojos (n = 400), 210 hombres, 190 mujeres, 248 jóvenes, 152 viejos, todos de raza blanca. Se hicieron dos grupos de pacientes distintos, un grupo por cada droga: propacaína 200 (PIO) ojos, oxibuprocaína 200 ojos. En cada grupo se sacó un promedio de PIO de 3 medidas antes, y 5 minutos después de la instilación del anestésico local. Mediciones hechas por un solo examinador y un solo tonómetro de aire (CT 8 Computerized Tonometer; Topcon). Resultados: Diferencia estadísticamente significativa entre valores promedio de PIO antes y después de la instalación de los anestésicos tópicos. Comparación entre medidas antes y después con promedio de más de 1 mmhg, alcanzando valores de hasta 7 mmhg en algunos casos. Para proparacaína la evaluación global del grupo (n = 200), mediciones promedio de PIO antes y después 16,62 mmhg (ds = 3,63) y 15,41 mmhg (ds = 3,65), respectivamente (95 por ciento IC = 0,99 a 1,41). Diferencia de 121 mmhg, t = 11,16, prueba de test de student g. L 199 p = 0,0000, muy significativo. Para oxibuprocaína la evaluación global del grupo (n = 200), mediciones promedio antes y después de 16,70 mmhg (ds = 3,69) y 15,68 mmhg (ds = 3,58) respectivamente (95 por ciento IC = 0,80 a 1,23), t Student, t = 9,40, g 1,199; p < 0,001. Diferencia 1,01 mmhg fue significativa. Conclusiones: Promedio de disminución de la PIO fue moderado (más de 1 mmhg). Diferencia en toma de presiones antes y después de las gotas fue significativa estadísticamente. Efecto de disminución de la PIO dado por los anestésicos tópicos puede conducir a subestimación de la PIO real medida con tonómetro de aplanación, resultando los valores reales de la presión ocular considerablemente superiores.

[Screening for glaucoma in diabetic patients by using the Schiörtz tonometer]. / Cribado del glaucoma en pacientes diabéticos mediante el tonómetro de Schiörtz.

OBJECTIVES: To assess the usefulness of measuring in primary care the intraocular pressure (IOP) of diabetics as a glaucoma screening test, validating the Schiörtz tonometer for this end. To analyse the prevalence of glaucoma and associated risk factors in our diabetic population. DESIGN: An observational crossover study. SETTING: Primary Care. Concentaina Health Centre. PATIENTS: 144 patients in our centre's diabetes mellitus health programme. MEASUREMENTS AND MAIN RESULTS: There were 31 cases of IOP over 20 mmHg measured with the Schiörtz tonometer, on whom the ophthalmologist repeated the measurement with the Perkins tonometer, i.e. viewing the back of the eye to confirm the existence of papillary cupping consistent with the presence of Glaucoma. We chose a group with normal IOP, homogeneous with the group with high IOP to validate the Schiörtz tonometer, using as confirmation the results obtained by the ophthalmologist with the Perkins tonometer; and as confirmation in the detection of glaucoma, finding papillary excavation in the binocular ophthalmoscopy. Prevalence of glaucoma was 11%, which was 75% in the newly diagnosed cases. The positive predictive value of the Schiörtz tonometer in detecting increases in IOP was 87.1%, and with respect to the detection of glaucoma, it was 35.5%. CONCLUSIONS: The high prevalence of glaucoma in diabetic patients justifies the systematic study of this risk factor. The Schiörtz tonometer is a useful and valid method, that can be used in primary care for glaucoma screening in this population group.

Ophthalmologic procedures in the emergency department--Part II: Routine evaluation procedures.

The emergency physician (EP) must be familiar with performance of ophthalmologic procedures for evaluation and treatment of a multitude of eye complaints. This article is the second of three articles addressing ophthalmologic procedures potentially of use by the EP. This article reviews the indications and the techniques for the following routine procedures: visual acuity testing, pupil dilatation, topical anesthesia use, and tonometry. Criteria for consultation also are addressed.