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Purpose This study examined characteristics of intraocular pressure (IOP) as measured during home tonometry in comparison with in-clinic tonometry in patients with glaucoma. Design Retrospective cross-sectional study of glaucoma patients who completed 1 week of self-tonometry at a single academic center. Participants Patients with glaucoma who completed home tonometry trials with the iCare HOME tonometer (iCare USA) for any reason. Methods Home IOP measurements were compared with in-clinic tonometry performed during the 5 visits preceding home tonometry. Maximum daily IOP was correlated to time of day. Generalized estimating equations were used to evaluate patient characteristics and clinic-derived variables that predicted differences between home and clinic IOP. Main Outcome Measures IOP mean, maximum, minimum, range, standard deviation and coefficient of variation were compared between clinic and home tonometry. IOP mean daily maximum (MDM) and mean daily range were calulated to describe recurrent IOP spiking. Results A total of 107 eyes from 61 patients were analyzed. Mean age was 63.2 years (standard deviation [SD], 14.0 years) and 59.0% were women. Mean clinic and home IOPs were 14.5 mmHg (SD, 4.7 mmHg) and 13.6 mmHg (SD, 5.1 mmHg). Home tonometry identified significantly higher maximum IOP, lower minimum IOP, and greater IOP range than clinic tonometry (P am –5 pm ) on 50% of days assessed and occurred between 4:30 am and 8 am on 24% of days. Mean daily maximum IOP exceeded maximum clinic IOP in 44% of patients and exceeded target IOP by 3 mmHg, 5 mmHg, or 10 mmHg in 31%, 15%, and 6% of patients, respectively. Patient characteristics that predicted significant deviations between MDM and mean clinic IOP or target IOP in multivariate models included younger age, male gender, and absence of prior filtering surgery. Conclusions Self-tonometry provides IOP data that supplements in-clinic tonometry and would not be detectable over daytime in-clinic diurnal curves. A subset of patients in whom home tonometry was ordered by their glaucoma clinician because of suspicion of occult IOP elevation demonstrated reproducible IOP elevation outside of the clinic setting. Such patients tended to be younger and male and not to have undergone previous filtering surgery.

Significance Assessment of treatment efficacy via comparison with a target IOP is fundamental in monitoring patients with open-angle glaucoma and ocular hypertension. This article highlights that diurnal IOP fluctuations obtained using self-tonometry may more accurately reflect IOP responses to therapy. Purpose This study aimed to investigate fluctuations in diurnal IOP measurements in patients with open-angle glaucoma and ocular hypertension treated with latanoprost 0.005% and timolol 0.25%. Methods In this crossover treatment trial, 14 participants performed self-tonometry with iCare HOME 4 times daily for (1) 1 week using latanoprost, (2) 4 weeks using no medications, and (3) 2 weeks using timolol. Daily peak IOPs, IOP fluctuations, and mean IOPs from different treatments were compared on an individual basis. Treatment efficacy between medications was assessed by comparing mean percentage IOP reductions with latanoprost and timolol across participants. In addition, effects of age, years since commencing latanoprost, sex, and diagnosis were investigated, and peak IOP times were compared with assess impacts on diurnal profiles. Results Between individuals, IOP responses ranged from reductions in peak IOPs, IOP fluctuations, and mean IOPs on both medications to no change in any parameter and medication. IOP fluctuations showed greater mean percentage reductions than did peak and mean IOPs (χ2 = 16.51, P = .002). There were significant associations between years since commencing latanoprost and peak and mean IOP responses on timolol (r = 0.69, P = .007), and sex and relative reductions in IOP fluctuations on both medications (P = .03). There were no differences in peak IOP times between treatment conditions. Conclusions Despite variability in IOP responses to latanoprost and timolol, IOP fluctuation with self-tonometry was more consistent in evaluating target IOP, reflecting its importance in ascertaining true IOP response to topical therapies. These findings may impact clinical decision making based on target IOP criteria in patients on topical therapy.

The Icare HOME (TA022, Icare Oy, Vanda, Finland) is rebound tonometer recently approved by the US Food and Drug Administration in March 2017 designed for self-measurement of intraocular pressure (IOP). IOP remains a major modifiable risk factor for glaucoma progression; however, IOP measurements typically occur through single office measurements on Goldmann applanation tonometry (GAT) and do not always reveal the complete picture of patient's IOP patterns and daily fluctuations, which are important for accurate diagnosis and evaluation. Numerous studies have now compared the efficacy of the Icare HOME to that of GAT. The objective of this article is to review the existing literature surrounding the Icare HOME tonometer and its efficacy as a self-tonometer in comparison to GAT. The available literature has shown promising results in its accuracy of measuring IOP but suggests cautious usage in patients with central corneal thicknesses or IOP ranges that are outside of a certain range. This article will also provide details and example cases for when the Icare HOME may be most clinically useful.

SIGNIFICANCE Icare HOME rebound tonometry is increasingly adopted into clinical practice for IOP phasing of glaucoma patients and suspects. Because of measurement differences with applanation tonometry and diurnal fluctuations, interpretation of the IOP measured with Icare HOME phasing can be challenging. PURPOSE The purpose of this study was to use a large patient cohort to develop a practical, analytical tool for interpreting Icare HOME measurements with respect to applanation pressure. METHODS IOP measurements using the Icare HOME and an applanation tonometer were taken prospectively in 498 consecutive patients. Bland-Altman, frequency distribution, and linear regression analysis were applied to determine measurement differences. A novel criterion, Threshold Icare HOME IOP, was developed to assist identification of elevation above target applanation pressure, considering the expected diurnal variation and measurement variability. RESULTS Icare HOME tended to underestimate applanation tonometry (mean bias, -1.7 mmHg; 95% limits of agreement, -7.0 to +3.6). Overall, differences were within ±3 mmHg in 71.5% and ±5 mmHg in 92% of patients. Based on the novel criterion developed, Icare HOME measurements that exceed target applanation pressure by 6 mmHg or greater are generally outside the 95% limit of expected observations. CONCLUSIONS The Threshold Icare HOME IOP is a novel and practical criterion that can assist clinicians in their interpretation of Icare HOME phasing measurements with respect to target applanation pressures. Elevation above the expected thresholds may prompt closer monitoring or even modifications to glaucoma management.

Introduction: The widespread availability of wearable sensors such as smart watches and activity trackers has made self-monitoring of parameters including heart rate mainstream. Self-monitoring is ...

Zur Feststellung von taglichen und nachtlichen Augeninnendruck(IOD)-Schwankungen, wie sie insbesondere bei Glaukompatienten haufig vorkommen, ist es notwendig, dass Patienten mindestens eine Nacht in spezialisierten Kliniken verbringen. Dies ist fur die Patienten haufig mit grosem Aufwand verbunden. Unser Ziel war es deshalb, die Einsatzmoglichkeit eines Rebound Tonometers (RT) zur IOD-Selbstmessung (RT-Home) in einem Praxisbetrieb zu testen insbesondere auserhalb der Sprechstundenzeiten und im Liegen. Uber einen Zeitraum von 6 Monaten stellten wir konsekutiv Offenwinkelglaukompatienten ein RT-Home fur eine Nacht zur Verfugung. Eingangs wurden vergleichende Messungen zwischen RT-Home, durchgefuhrt von arztlichem Personal (RT-Home[o]) und Patient (RT-Home[p]), sowie mit Applanationstonometrie nach Goldmann (GAT) erhoben. Zudem wurde die subjektive Bedienbarkeit des RT-Home mittels eines Fragebogens abgefragt. RT-Home(o) verglichen mit GAT zeigte eine Abweichung von −1,1 mm Hg (−7,9 bis 5,7 mm Hg). RT-Home(p) verglichen mit GAT zeigte eine Abweichung von −1,6 mm Hg (−8,9 bis 5,9 mm Hg). Der Messunterschied zwischen GAT und RT-Home(o), sowie RT-Home(p) korrelierte stark mit dem IOD und zentraler Hornhautdicke (IOD: r = 0,481, p > 0,0001 [RT-Home(o) vs. GAT]; Hornhautdicke: r = 0,612, p

Purpose: To evaluate and compare the accuracy of self-measurement of intraocular pressure using Icare Home rebound tonometer with Goldmann applanation tonometer and assess acceptability of self-tonometry in patients with glaucoma and ocular hypertension. Methods: In the study, 117 subjects were trained to use Icare Home for self-measurement. Icare Home tonometer readings were compared with Goldmann applanation tonometer, including one eye per patient. Agreement between the two methods of measurement was evaluated by Bland and Altmann analysis. Questionnaire was used to evaluate patients’ perception of self-tonometry. Results: One hundred and three out of 117 patients (88%) were able to measure their own intraocular pressure and 96 (82%) fulfilled the requirements for certification. The mean (SD) difference Goldmann applanation tonometer minus Icare Home was 1.2 (2.4) mmHg (95% limits of agreement, –3.4 to 5.9 mmHg). The magnitude of bias between the two methods depended on central corneal thickness, with greater bias at central corneal thickness Conclusion: Icare Home tonometry tends to slightly underestimate intraocular pressure compared to Goldmann applanation tonometer. Most patients were able to perform self-tonometry and found it acceptable for home use. Measurements using rebound self-tonometry could improve the quality of intraocular pressure data and optimize treatment regimen.

This study found good agreement between intraocular pressure measured by office-based and home tonometry. There was no difference in mean IOP, but home tonometry enabled measurements outside office-hours identifying greater fluctuation and higher IOP peaks.

Significance Peak IOP and IOP fluctuations have been implicated as risk factors for glaucoma progression. Peak 24-hour IOP can be significantly higher than in-office measurements. Icare HOME could be a useful adjunct in glaucoma management if positively appraised by individuals familiar with eye care. Purpose The purpose of this study was to measure the time needed for a nonclinical convenience sample of optometry students and optometrists to self-measure IOP using Icare HOME and to determine their perceptions of rebound self-tonometry. Methods A total of 234 subjects were enrolled, with 226 (97%) having a complete data set. Self-measurement was performed on the study eye using Icare HOME while seated and without contact lenses. Examiners self-measured IOP while subjects observed; examiners then measured subjects' IOP. Subjects then completed self-measurement while timed. Only one attempt was allowed. Time and study eye were recorded, and subjects completed a short survey. Descriptive statistics were conducted. Results Mean ± standard deviation age was 34.6 ± 13.3 years (58.3% female, 52.3% contact lens wearers). Test time ranged from 3 to 366 seconds, with 38% able to self-measure in 10 seconds or less, 74% in 60 seconds or less, and 92.8% in 120 seconds or less; 5.8% were unable to self-measure IOP. There was no significant correlation between test time and age (r = -0.03, P = .67). The device was reported to be easy or very easy to use by 69.7% of subjects and comfortable or very comfortable by 90.4% of subjects. After the study, 89.1% of subjects perceived that rebound self-tonometry has a role in the management of patients with glaucoma and suspicion of glaucoma. Conclusions The majority of neophyte subjects perceived self-measurement of IOP as having a role in the management of glaucoma and suspicion of glaucoma. They rated Icare HOME as comfortable and easy to use and were able to self-measure IOP on the first attempt.

Resume Objectif Le tonometre Icare® Home est un nouveau tonometre a rebond, developpe pour l’automesure de la pression intraoculaire (PIO). L’objectif principal de notre etude etait d’evaluer la fiabilite et la reproductibilite des mesures prises avec le tonometre Icare® Home, chez des patients glaucomateux, en comparaison avec le tonometre a aplanation de Goldmann. Un objectif secondaire etait de rechercher les facteurs pouvant influencer la reproductibilite de ces mesures. Materiels et methodes Cinquante-deux patients glaucomateux ont ete inclus dans cette etude prospective, non randomisee, monocentrique. Les mesures de la PIO ont ete realisees sur l’œil droit puis sur l’œil gauche, dans l’ordre suivant (3 mesures de la PIO pour chaque methode) : tonometre a Air (T-Air), tonometre Icare® Home par le patient (RT-P), tonometre Icare® Home par un ophtalmologiste (RT-O), tonometre a aplanation de Goldmann (GAT). Resultats Quarante-quatre patients (85 %) ont reussi a prendre leur PIO sur les 2 yeux avec le tonometre Icare® Home. Les PIO moyennes etaient de 14,35 ± 3,93 mmHg (T-Air), 13,43 ± 4,65 mmHg (RT-P), 14,13 ± 4,29 mmHg (RT-O), 14,74 ± 3,84 mmHg (GAT). Les indices de correlation intraclasse (ICC) sur 3 mesures repetees de la PIO etaient respectivement de 0,924, 0,872, 0,947 et 0,957. L’analyse de Bland-Altman retrouvait une difference moyenne (biais) entre GAT et RT-P, entre GAT et RT-O, et entre RT-O et RT-P, respectivement de 1,31, 0, 61 et 0,70 mmHg, avec un intervalle de confiance a 95 % respectivement de −3,34 a 5,96, −3,91 a 5,14 et −3,44 a 4,84 mmHg. La reproductibilite des mesures prises avec le tonometre Icare® Home ne variait pas selon l’epaisseur corneenne, ni selon l’âge des patients. Conclusion Le tonometre Icare® Home donne des valeurs fiables et reproductibles de la PIO chez les patients glaucomateux, meme s’il semble legerement sous-estimer les mesures de la PIO par rapport au tonometre a aplanation de Goldmann.

Purpose To evaluate the Icare HOME (TA022) device (Icare Oy, Vanda, Finland) for use by glaucoma patients for self-tonometry. Design Prospective performance evaluation of a medical device. Participants One hundred eighty-nine participants with glaucoma or suspected glaucoma were recruited from the Wilmer Eye Institute, Baltimore, Maryland, between July 2014 and April 2015. Methods Participants had standardized training and had to be able use the Icare HOME device independently. Subjects also had to be able to obtain the first intraocular pressure (IOP) measurement within 5 mmHg of Goldmann applanation tonometry (GAT). Those certified obtained 3 IOP measures using the HOME device, and these were compared with Icare TA01i and GAT IOP measurements. Main Outcome Measures The agreement between Icare HOME and reference tonometers was used to assess precision. The intraclass correlation coefficient was used to assess within-patient reliability for the HOME device. Results Eighteen of 189 recruited patients were ineligible to take part in the study. Forty-four of 171 patients (25.7%) started but failed to complete the study: 7 stopped because of time concerns, 10 of 171 patients (6%) stopped because of difficulty using the device during certification, and 27 of 171 patients (16%) failed to be certified based on IOP. The HOME and GAT measurements agreed within 5 mmHg in 116 of 127 participants (91.3%); 2 participants (1.6%) had a difference of more than 7 mmHg. The mean difference between the Icare HOME and GAT measurements was −0.33 mmHg (standard deviation, 3.11 mmHg). The overall intraclass correlation coefficient for the HOME device was 0.92 (95% confidence interval, 0.89–0.95). Conclusions Not all participants could learn how to use the Icare HOME device, but for those who could, most were able to obtain measurements similar to those obtained by GAT. The Icare HOME device is safe and reliable for self-tonometry, but nearly 1 in 6 individuals may fail to certify in use of the device based on large differences in IOP when comparing GAT with the Icare HOME measurements. The device has the potential to address an unmet need by providing more frequent IOP measurements in a patient's day to day life.

Purpose To evaluate the reliability of intraocular pressure measured by patients with glaucoma themselves using a new hand-held tonometer and to observe whether the intraocular pressure (IOP) variations have the same pattern on different days while glaucoma treatment is constant. Methods Eighty-seven patients diagnosed with open-angle glaucoma or ocular hypertension were recruited to the study. Intraocular pressure measured using Goldmann applanation tonometry (GAT) was compared with IOP measured using tonometry at baseline and on the second visit. Patients measured their IOP at home using the hand-held tonometers. Results The mean difference between GAT and iCare® values varies from 0 to 1 mmHg. Seventy-eight per cent of iCare® measurements were within 3 mmHg of the GAT measurements. Approximately 64% of the study eyes had higher IOP in the morning than in the afternoon/evening. Circadian patterns differed between consecutive days in 47% of the study eyes. There were IOP peaks outside office hours in up to 16% of the study eyes. Conclusion Measurements made using rebound self-tonometry are accurate and could be used to complement the investigation of patients with glaucoma. Intraocular pressure curves provide valuable data usable when adapting glaucoma treatment.

Hintergrund: Bei der Betreuung von Glaukompatienten spielt die gute Erfassung der Augendruckwerte und insbesondere deren mogliche Kurzzeit- aber auch Langzeitschwankungen eine wichtige Rolle. Die nicht invasive Selbsttonometrie durch die Patienten mit einem telemetrischen intraokularen Drucksensor kann wichtige Daten zum individuellen Augendruckprofil liefern. Patienten/Material und Methoden: Im Rahmen einer prospektiven klinischen monozentrischen Pilotstudie wurde bei 6 Patienten mit Offenwinkelglaukom die Implantation eines telemetrischen Drucksensors (ARGOS01) im Rahmen der Kataraktchirurgie in den Sulcus ciliaris durchgefuhrt. Im 5. Monat nach der Implantation wurde gemas dem Studienprotokoll ein Lesegerat zur Selbsttonometrie fur 1 Monat den Patienten mitgegeben. Die Patienten wurden aufgefordert, mindestens 1-mal pro Tag bzw. moglichst mehrfach zu messen. Ausgewertet wurde einerseits die 1. Messung des Tages (wobei 1 Messung pro Tag an 20 Tagen innerhalb des Intervalls erfasst wurde) sowie andererseits die Aufteilung der Werte nach Fruhphase (5–11 Uhr), Mittagsphase (11–16 Uhr) und Spatphase (16–23 Uhr) (Einschluss von Patienten mit mindestens 10 Werten und max. 20 Werten). Es erfolgte eine deskriptive Statistik mit Erfassung der Perzentile und Erstellung von Boxplots. Dabei wurden die Originalwerte des ARGOS-Systems verwendet. Ergebnisse: Bei allen Patienten konnte die Selbsttonometrie nach kurzer Anleitung problemlos durchgefuhrt werden. Bei der Auswertung der 1. Messung des Tages konnte eine sehr heterogene interindividuelle Spannweite der Augendruckwerte festgestellt werden (zwischen 3,1 mmHg bei Patient 5 und 21,7 mmHg bei Patient 4). Bei der Auswertung der Aufteilung der Werte nach der Tagesphase zeigten sich bei Patient 1 signifikant erhohte Druckwerte in der Spatphase. Bei Patient 5 waren die Mittagswerte im Vergleich zur Fruh- und Spatphase signifikant erhoht. Bei Patient 3 und Patient 4 konnten keine signifikanten Schwankungen wahrend des Tages festgestellt werden. Schlussfolgerung: Die Selbsttonometrie ermoglicht eine aktive Beteiligung des Patienten bei seiner Erkrankung und ermoglicht nicht invasiv eine gute Erfassung der Augendruckwerte zu verschiedenen Uhrzeiten und Aktivitaten. Wir mussen aber diese neuen Daten und deren klinische Bedeutung in Relation zur Goldmann-Applanationstonometrie interpretieren lernen.

Purpose To evaluate the accuracy of the intraocular pressure (IOP) measured by healthy subjects with icare® Home and to observe the IOP fluctuation and pattern of IOP fluctuation in healthy subjects over three consecutive days. Methods Sixty healthy subjects were recruited to the study. IOP was measured by the subjects themselves and by study staff using icare® Home tonometers on visits 1 and 2, as well as by study staff using Goldmann applanation tonometry (GAT). Furthermore, the subjects measured their IOP at home for three consecutive days. Results Twenty-three per cent of the study eyes were excluded in the statistical analysis due to dropout or non-compliance to the schedule. Approximately 70% of the icare® Home measurements were within 3 mmHg of the GAT measurements. Ten to 16% of the study eyes had IOP peaks outside office hours. Sixty-three per cent of the study eyes had different IOP patterns on consecutive days. Conclusion Rebound self-tonometry appears to be accurate and could be used to monitor short- and long-term IOP variations. The difference between IOP patterns on consecutive days raises questions as to the certainty of a single IOP measurement as a measure of treatment effect.

Glaucoma is the leading cause of irreversible blindness in the world. Diagnosis and management of glaucoma is significantly associated with intraocular pressure, but contemporary office-based measurements are not sufficient to discover diurnal changes and spikes, nor do they demonstrate the effect of medication and compliance. Patient-directed self-tonometry can be taken throughout the day and is therefore the subject of much discussion and research. In this article we review the history of self-tonometry devices and present technologies for the future.

Background: To compare intraocular pressures obtained using a handheld pressure phosphene tonometer (PPT) (Proview, Bausch & Lomb Pharmaceuticals, Inc., Tampa, Fla.) with Goldmann applanation tonometry. Methods: Comparative case series of 30 randomly selected patients. Results: The readings obtained with the pressure phosphene tonometer display a higher mean and a larger standard deviation than those obtained with the Goldmann applanation tonometer (GAT). Differences between PPT and GAT readings tended to decrease as a function of increased Goldmann levels. The relation of Proview and Goldmann readings ( r = 0.32) and the scatterplot were not consistent with the hypothesis that the 2 methods are equivalent. Interpretation: Our results indicate that the pressure phosphene-type handheld tonometry method, which does not appear to provide an accurate and consistent measure of intraocular pressure, is substantially less reliable than the Goldmann method.

To evaluate changes in patient compliance with medical treatment while using the Proview Eye Pressure Monitor.A crossover study design was used to compare the compliance of patients with established use of topical medication to lower intraocular pressure in the treatment of primary open-angle glaucoma. Thirty-two patients currently managed with latanoprost 0.005%, brimonidine 0.15%, travoprost 0.004% or bimatoprost 0.03% as monotherapy or in combination were randomly assigned to two study groups. Group 1 was instructed in the use of Proview Eye Pressure Monitor three times daily for 30 days as an adjunct to the glaucoma regimen. Group 2 was observed with no change in the patients' treatment regimen during this phase of study. A crossover occurred at 30 days. Compliance was monitored by assigning new bottles of topical medication during each phase of study. Bottles were weighed with a Mettler balance (Mettler Toledo Co.) at the initiation and completion of each phase. The changes in bottle-weight determined the amount of medication consumed by each patient for each phase of the study. The weights were analysed to estimate changes in compliance.A paired samples Student t-test compared the consumed bottle weights with and without Proview Eye Pressure Monitor usage. No statistical significance or trend was identifiable (p = 0.98). Use of the Proview Eye Pressure Monitor did not significantly change compliance with adjunct eye drop medication.The use of the Proview Eye Pressure Monitor use did not improve but appeared to hinder compliance with glaucoma treatment in this study.

Hintergrund: Die Druckphosphen-Tonometrie (DPT) ist eine psychophysische Methode, die auf der entoptischen Wahrnehmung von Druckphosphenen bei einer Erhohung des Augeninnendrucks basiert. Die Messmethode des Selbsttonometers Proview® basiert auf diesem Prinzip. In der vorliegenden Studie wurde die Zuverlassigkeit und Praxistauglichkeit dieses Tonometers im Vergleich zum Goldmann-Applanationstonometer (GAT) untersucht. Patienten und Methoden: Es wurden insgesamt 150 Augen von 62 gesunden Probanden und 88 Patienten mit chronischem Offenwinkelglaukom oder okularer Hypertension in die Studie eingeschlossen. Nach einer Ubungsphase erfolgte zunachst eine Messung des Augeninnendrucks mit dem GAT. Danach wurde von den Probanden eine Selbsttonometrie mit dem Proview® durchgefuhrt. Dabei erfolgten alle Messungen in sitzender Position. Ergebnisse: Fur alle untersuchten Augen (n = 150) fielen die Messwerte mit dem Proview® durchschnittlich 5,5 mmHg hoher aus als die mit dem GAT gemessenen Augeninnendruckwerte. Lediglich 34 % aller Messungen mit den beiden Verfahren lagen in einem Differenzbereich von ± 3 mmHg. Ein Vergleich zwischen Glaukompatienten mit nachgewiesenen Gesichtsfeldausfallen und gesunden Probanden bzw. Patienten mit okularer Hypertension ohne Vorliegen von Gesichtsfelddefekten ergab nahezu identische mittlere Differenzwerte zwischen dem Proview® und dem GAT. In beiden Gruppen wurden mit dem Selbsttonometer im Durchschnitt ungefahr 5,0 mmHg hohere Tensionswerte ermittelt. Schlussfolgerungen: Die Messwerte des Proview®-Tonometers zeigten im Vergleich zum GAT nur eine geringe Ubereinstimmung, sodass eine Selbsttonometrie, die auf der Basis einer subjektiven Wahrnehmung von Druckphosphenen beruht, in der Routinediagnostik nicht empfohlen werden kann. Beginnende Gesichtsfelddefekte scheinen keinen Einfluss auf die Augeninnendruckmessung mit dem Selbsttonometer zu haben. Background: The aim of this study was to compare the results of intraocular pressure (IOP) measurements obtained using the pressure phosphene tonometer Proview™ with those from Goldmann applanation tonometer (GAT) in normal and glaucomatous eyes. Patients and Methods: The IOP in 150 eyes of 62 healthy volunteers and 88 patients with glaucoma or ocular hypertension was measured prospectively in a sitting position. After being trained to use the Proview™ device, Goldmann applanation tonometry was performed first. Then the patient took a reading with the Proview™ self-tonometer. Results: For all investigated eyes the measurements with the Proview™ were on average 5.5 mmHg higher than those by GAT. Only 34 % of the readings from the two devices were within a difference range of ± 3 mmHg. On comparing the group of glaucomatous patients with slight visual field defects with the group of healthy subjects and patients with ocular hypertension without visual field defects we determined almost the same mean difference between the Proview™ and GAT (mean difference in the group with visual field defects = 4.7 ± 4.1 mmHg; without defects = 4.8 ± 2.9 mmHg). Conclusions: The tonometer Proview™ did not show a close agreement to GAT. Therefore, the PPT does not offer an alternative method for measuring IOP. We do not recommend the Proview™ for self-tonometry at home or for clinical management of patients with glaucoma. Slight visual field defects seem to have no influence on intraocular pressure measurement with the self-tonometer.

Background: Diurnal profiles of intraocular pressure at opening times in the doctor's office do not deliver enough information, especially nightly and early morning measurements are lacking. Self-tonometry using the automatic self-tonometer "Ocuton S®" might be suitable to achieve valid 24-hour IOP profiles without the need to stay in a hospital. Materials and Methods: 96 people were taught to use the automatic self-tonometer once. Those who had learnt self-tonometry after this training underwent a diurnal IOP profile for 24 hours in the hospital using Goldmann tonometry and self-tonometry every 4 hours at the same times of day. One to three days later, they created a third IOP profile at home using self-tonometry at the same intervals as at the hospital. The IOP profiles were then tested for equality. Results: 50 people out of 96 were able to perform self-tonometry after one training session. The IOP measurements of all three IOP profiles did not differ by more than 2 mmHg and thus may be considered comparable. There was no significant difference between daily curves, either. Conclusions: Self-tonometry using the automatic self-tonometer "Ocuton S®" appears to be suitable to record diurnal profiles of intraocular pressure at home.

Purpose To perform increased intraocular pressure (IOP) screening in non-glaucomatous patients after deep anterior lamellar keratoplasty (DALK) due to keratoconus with normal IOP measured during control visits. Methods Ten non-glaucomatous patients, who underwent DALK procedure due to keratoconus were included into study. Patients were measuring IOP using self-tonometer Icare One (Icare, Finland) continuously for 30 days, 3 times per each day. Additionally patients were checked by ophthalmologist 3-times during follow-up time in Outpatient Clinic, where applanation tonometry and central corneal thickness measurements were performed. After 30-days, self-measured IOP was evaluated for rises above 21 mmHg as well as rises above mean GAT values measured during control visits. Results Mean IOP measured with GAT and adjusted according to CCT was 15 mmHg and ranged between 11 and 19 mmHg. There were no values above 21 mmHg reported during follow-up time. In Icare One measurements, all patients showed incidents of IOP values higher than measured with GAT, however mean values ranged between 10-18 mmHg. Six out of 10 patients revealed to have IOP elevations higher than 21 mmHg between control visits (with maximum values up to 46 mmHg), and this elevated values constituted from 3.3 up to 20.0 % of all self-measurements. Conclusion Self-tonometry with Icare One might be useful tool to identify patients who develop undetectable IOP increases between control visits. This can help in prevention of vision loss and transplant procedure failure in DALK patients.

Purpose: To compare 24-hour diurnal intraocular pressure (IOP) measurements obtained using the Ocuton-S applanation self tonometer and the Goldmann tonometer. Methods: 24-hour diurnal IOP curves were obtained on 14 eyes of 7 trained patients suffering from medically controlled primary open angle glaucoma. IOP was measured every third hour starting at 9 a.m. with a calibrated Goldmann tonometer; one week later, a similar set of measurements was obtained with Ocuton-S self tonometry by the patients. One week later still, ultrasound corneal pachymetry was performed at the same hours. Results: Overall IOP (24-hour mean) did not differ significantly between the different measuring techniques (ANOVA, p=0.74), but the IOP differed in a statistically significant manner around the clock (ANOVA, p=0.00006). The mean Goldmann tonometric readings were up to 2.8 mmHg lower than the Ocuton-S values during the daytime (9 a.m. to 9 p.m.), however, during the night (12 midnight to 6 a.m.) mean IOP measured with Goldmann tonometry was 2.2 to 3.3 mmHg higher than the corresponding average of the self tonometry readings. There was a statistically significant interaction between the type of tonometry and the time of the measurement (p=0.0007). Central corneal thickness (CCT) showed a significant change during the 24-hour period (p=0.000001). Conclusion: IOP shows a different diurnal curve when measured with the Goldmann tonometer and with the Ocuton-S applanation self tonometer. The instruments’ readings might be influenced in different ways by the diurnal changes of the corneal thickness. Since Ocuton-S self tonometry underestimates the IOP in the early morning period, a careful evaluation is necessary when nocturnal and early morning IOP elevation is investigated with this technique.

Studies have shown that pressure phosphene tonometry (PPT) may be applied to glaucoma patients. It has the potential for patients to self-monitor the intraocular pressure (IOP) at home. We describe the successful use of this approach in a patient with Posner-Schlossman syndrome. In the first part of the study, we investigated whether our patient could use PPT accurately and reliably. In the second part of the study, our patient performed daily home self-tonometry, and was educated to seek ophthalmic assessment if his self-measured IOP was >or=21 mmHg. The outcome measurements included IOP and the number of unscheduled attendances for ophthalmic assessment. The use of PPT reduced his number of unscheduled hospital visits from 0.82 to 0.47 visits per month. PPT can be applied with accuracy, reliability and safety in patients with Posner-Schlossman syndrome, with potential benefits in reducing unnecessary ophthalmic attendances by nearly 50%.

Der Untersuchungsgegenstand der vorliegenden Arbeit ist das Druckphosphentonometer ProviewTM (Bausch & Lomb Inc.), dessen Funktionsprinzip auf der Wahrnehmung des Phosphen-Phänomens basiert. Das Hauptziel bestand in der Überprüfung der Messgenauigkeit des Druckphosphentonometers ProviewTM (DPT) im Vergleich zum Goldmann-Applanationstonometer (GAT) bei Glaukompatienten und Personen ohne Glaukom. Hierzu wurde eine klinische Studie mit 170 Probanden durchgeführt. Nach einer ausführlichen Einweisung konnten 150 Probanden das Phosphen-Phänomen wahrnehmen. Im Anschluss an eine mehrtägige Übungsphase erfolgten bei den 62 Kontrollprobanden und 88 medikamentös behandelten Glaukompatienten zuerst eine Augeninnendruck(AID)-Messung mit dem GAT durch den Arzt und anschließend drei selbstständige AID-Messungen mit dem DPT durch die Studienteilnehmer. Um das DPT in seiner Wertigkeit als Heimtonometer zu prüfen, haben 42 Kontrollprobanden und 18 Glaukompatienten mit anfänglichen Gesichtsfeld- und Sehnervenbefunden zusätzlich an der Erhebung der Druckprofile zu vier Tageszeiten teilgenommen. Die Ergebnisse zeigen, dass eine Nicht-Wahrnehmung des Phosphens mit einem höheren Alter (p, Objective: To examine the accuracy of Pressure Phosphen Tonometer ProviewTM (Bausch &Lomb; Inc.) (PPT) compared to Goldmann applanation tonometer (GAT) in glaucoma patients and persons without glaucoma. Methods: One hundred and seventy subjects have participated in the clinical study. After a detailed briefing 150 subjects perceived the phosphene phenomenon. Sixty two control subjects and 88 primary open-angle glaucoma patients with use of topical medication to lower intraocular pressure (IOP) were measured with the GAT by the examiner and then three separate IOP measurements with PPT were done by the study participants. To check the PPT as a home tonometer 42 control subjects and 18 glaucoma patients with initial visual field and optic nerve defect(s) participated in the survey of pressure profiles at four time points of the day. Results: PPT measures generally higher IOP values than GAT. The extent of the deviation depends on the characteristics of the optic nerves and visual field defect(s) as well as on the measuring technique with the PPT. In glaucoma patients with glaucomatous damage of 0.7-0.8 cup-to-disc-ratio and middle visual field defects only 12.7% of the measured values were located in the clinically acceptable tolerance range of |≤3| mmHg. The mean of the IOP differences between the two methods of measurement in this group was 7.97 ± 4.42 mmHg. In the control subjects and glaucoma patients with ≤0.6 cup-to- disc-ratio and initial glaucomatous visual field defect(s) were the respective shares of the measurements in the range of |≤3| mmHg significantly higher (55% and 57%). The mean values of IOP differences were 3.18 ± 3.08 mmHg and 3.09 ± 2.81 mmHg, respectively. Among the control subjects and the glaucoma patients in initial stage of glaucoma, who were previously performed home tonometry with the PPT, were 64% and 70% of the measurement results within the tolerance range. The mean values were 2.36 ± 2.09 mmHg and 2.89 ± 1.75 mmHg, respectively. This is especially caused by learning and adaption effects and suggests that training can improve the agreement with GAT. The IOP curves measured with the PPT describe in both examined groups the physiological IOP course. The amplitude of the PPT collected daily pressure profiles in the control subjects was 3.19 ± 1.04 mmHg and in the glaucoma patients was 3.33 ± 1.14 mmHg. Each of them was with high significance (p

To compare intraocular pressure (IOP) measurements obtained by the Icare ONE rebound tonometer (RTONE) and the Goldmann applanation tonometer (GAT) in healthy persons and glaucoma patients in a prospective study, and to investigate the influence of central corneal thickness (CCT).Measurements on 126 right eyes were obtained by three equally skilled ophthalmologists with each of the above-mentioned tonometers. In addition, patients measured their own IOP with the RTONE (RTONE(p)). The means and standard deviation for all tonometers were compared. Agreement between the tonometers was calculated using the Bland-Altman method.A total of 95 (75.3%) patients were able to perform correct self-tonometry. Mean IOPs obtained were 17.1 ± 5.9 mmHg (RTONE performed by ophthalmologist: RTONE (o)), 17.3 ± 5.6 mmHg (RTONE(p)) and 16.5 ± 5.1 mmHg (GAT). Correlation analysis indicated a good correlation between IOP readings obtained using RTONE(o) and RTONE(p) (ρ = 0.916; p 0.001) and RTONE(o) and GAT (ρ = 0.901; p0.001). Bland-Altman analysis revealed a mean difference (bias) between RTONE(o) and RTONE(p), between RTONE(o) and GAT, and between RTONE(p) and GAT of -0.2, 0.6, and 0.8 mmHg, respectively, with 95% limits of agreement of -5.0 to 4.5, -4.4 to 5.6, and -4.6 to 6.1 mmHg, respectively. The difference between RTONE(o) and GAT significantly increased with increasing CCT (ρ = 0.004), with a 10% increase in CCT resulting in a 1.8% increase in the difference.Measurements obtained with the RTONE, either by an ophthalmologist or by the patient, showed an excellent correlation with those provided by applanation tonometry. RTONE generally tends to overestimate IOP compared to GAT readings and displays a dependence on CCT. This study was registered with the DRKS (German Clinical Trials Register; www.germanctr.de ; DRKS00000478).

PURPOSE. To evaluate whether the pressure phosphene tonometer (PPT) is suitable for self-tonometry in patients with glaucoma or ocular hypertension. METHODS. This was a prospective comparative study of 102 eyes of 102 patients with chronic glaucoma or ocular hypertension. Intraocular pressure (IOP) measurements by the Goldmann tonometer (GT) were compared with self-measured readings with the PPT. Patients evaluated the ease of home use of the PPT. The last 15 patients were asked to stop their glaucoma medications, and the ability of the PPT to detect an elevated IOP during self-tonometry was studied. RESULTS. The mean SD difference between PPT and GT readings was 0.24 1.57 mm Hg. Comparing the PPT with the GT, 86% of the readings were within 2.0 mm Hg, and 91% were within 3.0 mm Hg. Spearman’s correlation coefficient was 0.91. A Bland-Altman plot showed that the 95% limits of agreement between the two methods lay between 2.90 and 3.38 mm Hg. Within-subject coefficients of variation for the GT and the PPT were 4.4% and 7.3%, respectively. In detecting an elevated IOP of more than 21 mm Hg, the sensitivity and the specificity of the PPT were 92.3% and 98.6% respectively. The mean satisfaction score for home use of the PPT was 87.4 16.3 (maximum 100). CONCLUSIONS. With proper training and technique, self-tonometry with the PPT appears to be accurate up to at least 25 mm Hg and is reproducible. The PPT was sensitive and specific in detecting an elevated IOP of more than 21 mm Hg. As patients were expected to seek ophthalmic care before the self-measured IOP reaches 25 mm Hg, the PPT may have a value for self-monitoring. Patients rated the PPT as satisfactory for home use. Because the PPT is portable and relatively inexpensive and requires no topical anesthesia or direct contact with the eyeball, it may have potential as an instrument for home self-tonometry. (Invest Ophthalmol Vis Sci. 2004;45:3131–3136)

Background: To compare two methods of measuring intraocular pressure (IOP) and to evaluate whether repeated measurements taken with the Ocuton S applanation self-tonometer can improve reliability. Methods: Ocuton S and Goldmann applanation tonometry (GAT), and corneal thickness measurements taken with the Orbscan topography system, were successfully performed in 64 of 68 glaucoma patients. Results: The median IOPs were 15.5 mmHg using GAT, and 16 mmHg using the first self-taken Ocuton S measurement (n = 64). The differences between the median of the GAT measurements and the first Ocuton S measurement, and the medians of the three and six separate Ocuton S measurements were within 3 mmHg in 52%, 59% and 67% of cases, respectively. The mean corneal thickness of all evaluated eyes was 545.3 µm. There was no effect of corneal thickness on the accuracy of either of the two devices (p > 0.05). Conclusion: Repeated measurements can improve the reliability of the Ocuton S. However, even with repeated measurements only every second patient succeeds in obtaining reliable measurements.

The authors considered the possibility of using the Pulsair-Keeler non-contact tonometer in self-tonometry. For this reason, 45 patients have been trained to use the instrument and, after a reasonable trial period, were able to self-measure their IOP. The results have been compared to the tonometric values measured with Goldmann tonometer to evaluate statistically the limits and the dependability of this method of measurement. The results shows that self-tonometry with the Pulsair-Keeler tonometer can be used in monitoring glaucomatous patients at home.

· Background: The purpose of the study was to evaluate the acceptance and reproducibility of a new self-tonometer (Ocuton S) and to compare it with the Goldmann applanation tonometer. · Methods: The Ocuton S was studied in 20 healthy volunteers and 100 patients. After detailed explanation to each individual and a number of test measurements, we studied the reproducibility and accuracy of the Ocuton S in 20 healthy volunteers with and without topical anaesthesia. Acceptance was graded by means of visual analogue scales. Each volunteer had to measure his/her own IOP in three consecutive measurements. The data were compared with Goldmann tonometry at random times. One hundred patients were introduced to the Ocuton S. Either three consecutive self-measurements of IOP were performed and then compared with three consecutive measurements by Goldmann tonometry, or vice versa. This was done randomly. · Results: Forty-one of 100 patients were unable to perform three consecutive measurements with the Ocuton S after at least 15 min introduction time to the device (non-success). Fifty-nine of 100 patients were able to measure their IOP with the Ocuton S. The mean pressure value with the Ocuton S was 23.2±8.2 mmHg, compared with Goldmann 18.4±5.7 mmHg. The difference of 5±5.7 mmHg was statistically significant (paired t-test p

Microgravity leads to a "fluid shift" towards the upper parts of the body and, therefore, to a rise of the intraocular pressure. Parabolic flights have also demonstrated some rise of the intraocular pressure. During the first German Spacelab mission D1, changes of the intraocular pressure were investigated for the first time in space. The first pressure readings were obtained 44 min after entering microgravity and showed a pressure rise of 20 to 25% compared to the baseline data. To get earlier measurements in microgravity a fully automatic self-tonometer was developed which functioned independent of position and microgravity. It was used during an 8-d manned space mission in March 1992. Measurements of the intraocular pressure have been performed 16 min after reaching microgravity. The pressure readings revealed a 92% rise of the intraocular pressure compared to the daytime-correlated baseline data on Earth.