Easyton® transpalpebral versus Perkins applanation tonometry in different populations.

OBJECTIVE:  To compare intraocular pressure (IOP) measurements obtained using the new transpalpebral Easyton® tonometer and Perkins applanation tonometer (PAT) in three different clinical populations. METHODS: The participants of this prospective study were 84 subjects divided into the groups: 22 healthy children (G1), 42 healthy adults (G2), and 20 adult patients with primary open angle glaucoma (G3). The data recorded in 84 eyes of these subjects were age, sex, gender, central corneal thickness (CCT), and axial length (AL). In all eyes, IOP was determined in the same examination room by the same experienced examiner using Easyton® and PAT in random order. RESULTS:  Mean differences in IOP readings between Easyton® and PAT were 0.45 ± 1.97 (p = 0.295), - 0.15 ± 2.13 (p = 0.654), - 1.65 ± 3.22 (p = 0.033), and - 0.018 ± 2.50 mmHg (p = 0.500) in the groups G1, G2, G3, and whole sample (G4), respectively. Correlations between Easyton® and PAT IOP values were 0.668 (p = 0.001) for G1, 0.463 (p = 0.002) for G2, 0.680 (p < 0.001) for G3, and 0.605 (p < 0.001) for G4. Moderate to good agreement between the two tonometers was found in all groups according to intraclass correlation coefficients, which were 0.794 (p < 0.001) for G1, 0.632 (p < 0.001) for G2, 0.809 (p < 0.001) for G3, and 0.740 (p < 0.001) for G4. The lower and upper limits of agreement between the devices were - 5.1 and 4.7 mmHg, respectively, in the complete group. No correlation was noted between CCT or AL and the Easyton® IOP measurements. CONCLUSION: IOP measurements obtained with Easyton® and PAT show an acceptable level of agreement mainly in healthy individuals, recommending it for IOP screening in children and in patients in which PAT measurement may be impared as patients with hemifacial spasms, corneal irregularities, or reduced mobility. It is not recommended for glaucoma patients follow-up.

Peripapillary and macular vascular parameters by optical coherence tomography angiography in primary congenital glaucoma.

OBJECTIVE: To evaluate the differences in peripapillary and macular vascular parameters by optical coherence tomography angiography (OCTA) between patients with primary congenital glaucoma (PCG) and healthy controls; and to determine their diagnostic accuracy. MATERIAL AND METHODS: Observational, cross-sectional study including 39 eyes with PCG and 78 healthy eyes. Only one eye per patient was included. All included patients underwent a comprehensive ophthalmic examination and peripapillary and macular analysis were performed by AngioplexTM OCTA (Cirrus HD-OCT 5000) with a 4.5 × 4.5 mm optic nerve head scan and 6 × 6 mm macular scan. Global data and quadrant data from peripapillary vascular parameters and global data and circular sectors data from macular superficial plexus parameters were compared between groups. The glaucoma discrimination capability of these parameters was calculated as areas under the receiver operating characteristics curve (AUC ROC). RESULTS: Mean age was 14.1 ± 8.7 years for the PCG patients and 11.7 ± 6.2 years for controls (p = 0.093). All vascular peripapillary measurements (global and quadrants; all p < 0.001) and all macular measurements (p < 0.042) excepting perfusion density in the inner circle (p = 0.087), were reduced in the PCG group compared to controls. According to AUC ROC, peripapillary (all ≥ 0.706) and macular parameters (all ≥ 0.699) showed good diagnostic capacity. AUC ROC for the most discriminatory measurements corresponding to blood flux index (0.887) and whole macula vascular density (0.855) were similar (p = 0.085). CONCLUSION: Peripapillary and macular vascular parameters by OCTA are decreased in patients with PCG, showing a good capacity to discriminate between normal and glaucomatous eyes.

Effects of Corneal Biomechanical Properties on Rebound Tonometry (Icare200) and Applanation Tonometry (Perkins) Readings in Patients With Primary Congenital Glaucoma.

OBJECTIVE: The aim was to assess the influence of corneal biomechanics on intraocular pressure (IOP) measurements made with the Icare200 (IC200) rebound tonometer and the Perkins handheld applanation tonometer in patients with primary congenital glaucoma (PCG). MATERIALS AND METHODS: A total of 40 PCG patients and 40 healthy controls, age, and sex-matched, were recruited. IOP was measured with the Ocular Response Analyzer (IOPc, IOPg), IC200 and Perkins. The variables age, IOP, corneal hysteresis (CH), corneal resistance factor (CRF), central corneal thickness (CCT), best-corrected visual acuity, spherical equivalent, medications, and glaucoma surgeries were recorded for each subject. Univariate and multivariate analysis were used to detect effects of variables on IOP measurements. RESULTS: Mean CCT was 545.65±71.88 µm in PCG versus 558.78±27.58 µm in controls (P=0.284). CH and CRF were significantly lower in PCG group than in control group: mean CH 8.11±1.69 versus 11.15±1.63 mm Hg (P<0.001), and mean CRF 9.27±2.35 versus 10.71±1.75 mm Hg (P=0.002). Mean differences between IOP IC200-Perkins were 0.79±0.53 mm Hg in PCG versus 0.80±0.23 mm Hg in controls (P<0.001) and mean differences IC200-IOPc were -0.89±5.15 mm Hg in PCG (P<0.001) versus 1.60±3.03 mm Hg in controls (all P<0.009). Through multivariate analysis, CRF showed positive association and CH negative association with IOP measured with Perkins or IC200 in both subject groups. No association was detected for CCT, age, or sex. CONCLUSION: CH and CRF were identified as the main factors interfering with IOP measurements made with both tonometers in patients with PCG and healthy controls.

Clinical outcomes of combined Preserflo Microshunt implantation and cataract surgery in open-angle glaucoma patients.

To assess the effectiveness and safety of the Preserflo Microshunt (PMS) implantation combined with cataract surgery in open-angle glaucoma (OAG) patients. Retrospective, open-label study conducted on insufficiently controlled OAG patients, who underwent a PMS implant procedure with mitomycin-C 0.2%, either alone or in combination with cataract surgery, and were followed for at least 12 months. Success was defined as an intraocular pressure (IOP) ≤ 18 mmHg and a reduction of at least 20% without (complete) or with (qualified) hypotensive medication. Fifty-eight eyes were included in the study, 35 eyes underwent PMS alone and 23 underwent PMS + Phaco. In the overall study sample, mean IOP was significantly lowered from 21.5 ± 3.3 mmHg at baseline to 14.6 ± 3.5 mmHg at month 12 (p < 0.0001). The IOP was significantly reduced in both groups; p < 0.0001 each, respectively. Ocular hypotensive medication was significantly reduced (p < 0.0001) in both groups. No significant differences were observed in IOP lowering or medication reduction between groups. At month 12, 62.1% eyes were considered as complete success and 82.8% eyes as qualified success. The most common adverse events were device close-to-endothelium, conjunctival fibrosis, and wound leakage. PMS, either alone or in combination with phacoemulsification, may be considered as a valuable option for treating OAG patients.

Agreement between rebound (Icare ic200) and applanation tonometry (Perkins) in patients with primary congenital glaucoma.

PURPOSE: To examine agreement between intraocular pressure (IOP) measurements made using the rebound tonometer Icare ic200 (RT200) and the Perkins handheld applanation tonometer (PAT) in patients with primary congenital glaucoma (PCG). The impacts of several covariables on measurements using the two devices were also assessed. MATERIALS AND METHODS: Intraocular pressure measurements were made in a single session in 86 eyes of 86 patients with PCG (46 under anaesthesia, 40 in the office). The order was RT200 then PAT. The variables age, central corneal thickness (CCT), corneal state and anaesthesia were recorded in each patient. Data were compared by determining interclass correlation coefficients (ICC) for each tonometer and representing the differences detected as Bland-Altman plots. Effects of covariables were assessed through univariate and multivariate regression. RESULTS: Mean IOP difference between tonometers (RT200 minus PAT) was 1.26 mmHg (95%: 0.22-2.31). Absolute agreement (ICC) was 0.73 (95% CI: 0.62-0.82). Lower and upper limits of agreement (95%) were -8.06 mmHg (95% CI: -9.87 to -6.25) and 10.59 mmHg (95% CI: 8.77-12.40), respectively. The tonometers showed systematic differences (a = -4.63 mmHg; 95% CI: -9.11 to -1.44) and proportional differences; for each mmHg increase in PAT-IOP, the RT200 reading increased by 1.28 mmHg (b = 1.28; 95% CI: 1.12-1.53). None of the variables tested as predictors were able to explain differences between the tonometers. CONCLUSIONS: Despite the good overall agreement between both tonometers, caution should be taken in high values of IOP, considering the interchangeability of its readings as systematic and proportional differences appear to exist between both methods.

Diagnostic capacity of SD-OCT segmented ganglion cell complex versus retinal nerve fiber layer analysis for congenital glaucoma.

PURPOSE: To compare the diagnostic performance of circumpapillary retinal nerve fiber layer (cpRNFL) analysis versus segmented ganglion cell complex analysis both by spectral-domain optical coherence tomography (SD-OCT) in children with primary congenital glaucoma (PCG). METHODS: Participants were 40 children diagnosed with PCG and 60 healthy children. Ophthalmological data collected (for one eye per child) were cup-disc ratio (C/D) and axial length (AL). SD-OCT with automated segmentation was used to measure the thicknesses and volumes of the macular retinal nerve fiber layer (mRNFL), ganglion cell layer (GCL), and inner plexiform layer (IPL). For the cpRNFL measurements conventional S-D OCT software was used and the capacity of each method to discriminate between normal and glaucomatous eyes was compared. RESULTS: Mean age was 11.20 ± 3.94 years for the glaucoma patients and 10.90 ± 2.46 years for controls (p = 0.64). All measurements were reduced (thinner) in the glaucoma group, significantly so for: cpRNFL, GCL, IPL and outer-superior and outer-inferior quadrant mRNFL. According to their areas under the receiver operating characteristics curve (AUC), temporal superior cpRNFL (0.869) and outer superior GCL (0.840), IPL (0.799), and mRNFL (0.767) showed the better diagnostic capacity. No differences were observed in AUCs for the most discriminatory cpRNFL and macular measurements. CONCLUSION: Segmented macular layer analysis shows a good capacity to discriminate between normal and glaucomatous eyes; which is comparable to that of cpRNFL analysis in children with PCG.

New technologies for measuring intraocular pressure.

The level of intraocular pressure (IOP) is the main known risk factor for the development and progression of glaucomatous optic neuropathy. Despite Goldmann applanation tonometry (GAT) being the gold standard for determining IOP since the last century, its limitations were obvious from the start and include substantial effects of several eye variables such as axial length, curvature, rigidity, and corneal thickness. These limitations have prompted the development of numerous formulas and nomograms designed to compensate for the ocular characteristics effect on GAT, but none of these methods has been entirely satisfactory. Similarly, as a result of efforts to mitigate some of the limitations of conventional tonometry, several new tonometers have appeared on the scene.

Diplopia from pleomorphic lipoma of the orbit with lateral rectus muscle involvement.

A-55-year-old man with a 2-year history of left proptosis with painless swelling of the upper and lateral bulbar conjunctiva was referred. He had developed diplopia in left gaze. Orbital CT showed left proptosis with a mass measuring 2 × 1 cm in the superolateral and lateral left orbit, with lateral rectus muscle infiltration. The lesion was excised and was found to be diffuse, and an infiltrative mass affecting the anterior portion of the lateral rectus muscle was also removed. The histopathologic diagnosis was pleomorphic lipoma. Only 7 cases of pleomorphic lipomas occurring in ocular adnexal tissues or in the orbit have been previously reported, but in none of the cases had an infiltration of the lateral rectus muscle or diplopia been described before. The histopathologic features and differential diagnosis of this type of soft tissue tumor are also described.