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.

Inventory of Ocular Pulse Amplitude Values in Healthy Subjects and Patients With Ophthalmologic Illnesses: Systematic Review and Meta-analysis.

PURPOSE: Many studies have examined the ocular pulse amplitude (OPA) to better understand its physiology and clinical relevance, but the papers are scattered, not consistently indexed, and sometimes difficult to locate. We aimed to identify and summarize the relevant published evidence on OPA and, in a meta-analysis, outline specific differences of this parameter between healthy individual, primary open-angle glaucoma, normal-tension glaucoma, ocular hypertension, and cataract patients. DESIGN: Systematic review and meta-analysis. METHODS: A thorough literature search and data extraction were conducted by 2 reviewers independently. Reports on OPA measured by the dynamic contour tonometry in conjunction with different ocular and systemic diseases or potential influencing factors were included. RESULTS: Of the 527 initially found reports, 97 met the inclusion criteria assessing 31 clinical conditions. A meta-analysis based on 6850 eyes and 106 study arms (68.8%) revealed differences in mean OPA values in millimeters of mercury between various entities. Among healthy eyes, the OPA was 2.58 mm Hg (95% CI: 2.45-2.71), whereas OPA values were higher in glaucoma (unspecified glaucoma 2.73 mm Hg, 95% CI: 2.38-3.08; normal-tension glaucoma 2.66 mm Hg, 95% CI: 2.36-2.97; and primary open-angle glaucoma 2.92 mm Hg, 95% CI: 2.75-3.08). Although ocular hypertension showed the highest OPA values (3.53 mm Hg, 95% CI: 3.05-4.01), the lowest values were found in cataract eyes (2.26 mm Hg, 95% CI: 1.57-2.94). CONCLUSION: We found different OPA values characteristic of different clinical entities, with above-normal values in glaucoma and ocular hypertension and lower values in cataract patients. Our work is intended for clinicians and researchers who want to get a quick overview of the available evidence or who need statistical data on OPA distributions in individual diseases.

Intraocular Pressure in Eyes with Intraocular Lens Dislocation and Pseudoexfoliation Syndrome.

PURPOSE: To investigate intraocular pressure in eyes with intraocular lens subluxation and pseudoexfoliation syndrome. METHODS: In this retrospective study conducted at one eye centre (tazz) in Zurich, Switzerland, we reviewed 85 eyes with intraocular lens subluxation and pseudoexfoliation syndrome. Intraocular lens exchange was carried out by two surgeons between 03/2016 and 12/2019 (45 months). Information on baseline characteristics and diagnosis of glaucoma was recorded. Intraocular pressure and best-corrected visual acuity were analysed preoperatively and at five time points up to 12 months after lens exchange. Data on antiglaucomatous medication was collected before surgery and at two different time points after surgery. Postoperative pressure lowering procedures and complications were further analysed. RESULTS: This study includes 85 pseudoexfoliation eyes with intraocular lens subluxation. The mean interval between cataract surgery and lens exchange was 8.9 ± 5.2 years. Intraocular pressure elevation in the event of intraocular lens subluxation was found in 54% (46/85) of eyes. Mean intraocular pressure decreased from 22.9 ± 9.4 mmHg preoperatively to 15.2 ± 3.4 mmHg at follow-up 12 months after lens exchange (p < 0.001). Postoperative topical antiglaucomatous drug requirements were comparable to preoperative levels (p = 0.520). Less systemic acetazolamide was required 12 months postoperatively (p = 0.018). A pressure lowering procedure was required in seven (8%) eyes in the postoperative period due to persistence of high intraocular pressure. Intermittent increase or persistence of high intraocular pressure occurred in 13 (15%) eyes. CONCLUSION: This study emphasises the connection between acute pressure elevation and intraocular lens subluxation in patients with pseudoexfoliation syndrome. Intraocular pressure decreases after lens exchange and decrease sustains for a postoperative period of 12 months. Postoperative pressure lowering procedures were not required in the majority of eyes. We therefore conclude that intraocular lens exchange is efficient in the management of lens subluxation and pressure elevation in patients with pseudoexfoliation syndrome.

Two Surgical Approaches for Intraocular Lens Dislocation: Pars Plana Vitrectomy Versus Core Vitrectomy with Lens Exchange.

PURPOSE: To compare the efficacy and safety of core vitrectomy and pars plana vitrectomy for lens exchange in patients with intraocular lens dislocation. METHODS: This is a retrospective study conducted at one eye center in Zurich, Switzerland. We reviewed 124 eyes with dislocated intraocular lens undergoing lens exchange carried out by two surgeons between 03/2016 and 12/2019 (45 months). Intraocular pressure (IOP) and best-corrected visual acuity (BCVA) were analyzed preoperatively and at 5 time points up to 12 months after lens exchange. Data on postoperative complications were collected. RESULTS: There were 124 eyes with intraocular lens dislocation that were referred for lens exchange. Of these eyes, 59 (48%) received core vitrectomy and 65 (52%) received pars plana vitrectomy with lens exchange. Glaucoma was more frequent in the core vitrectomy group (78%) than in the pars plana vitrectomy group (32%; p < 0.001). In the core vitrectomy group, 19 (32%) eyes presented with visual impairment, 17 (29%) eyes presented with high IOP alone, and 23 (39%) eyes presented with both at the same time prior to surgery. Mean preoperative IOP in the core vitrectomy group decreased from 22.4 ± 9.2 mmHg to 14.7 ± 3.1 mmHg 12 months after surgery (p < 0.001). Mean BCVA changed from 0.40 ± 0.41 logMAR preoperatively to 0.32 ± 0.37 logMAR at 12 months postoperatively (p = 0.598) in the core vitrectomy group. In the pars plana vitrectomy group, 44 (68%) eyes presented with a change in vision, 7 (11%) eyes presented with high IOP alone, and 14 (22%) eyes presented with pressure elevation and visual impairment at the visit prior to surgery. Mean preoperative IOP in the pars plana vitrectomy group decreased from 20.9 ± 8.3 mmHg to 15.1 ± 3.5 mmHg at 12 months after lens exchange (p < 0.001). Mean BCVA in the pars plana vitrectomy group was 0.57 ± 0.62 logMAR preoperatively and 0.22 ± 0.35 logMAR 12 months postoperatively (p < 0.001). Postoperative pressure decompensation occurred more frequently in the core vitrectomy group (20%) than in the pars plana vitrectomy group (6%; p = 0.018). There was no statistically significant difference for postoperative cystoid macular edema (p = 0.055), anisometropia (p = 0.986), and high astigmatism (p = 0.362). CONCLUSION: Core vitrectomy and pars plana vitrectomy with lens exchange are equally efficient and safe in the management of intraocular lens dislocation.

Comparison Between the eyeWatch Device and the Ahmed Valve in Refractory Glaucoma.

PURPOSE: To assess the efficacy and safety of a glaucoma procedure to control intraocular pressure (IOP) using the adjustable eyeWatch glaucoma drainage device compared with Ahmed glaucoma valve (AGV) in refractory glaucoma. PATIENTS AND METHODS: Monocentric, retrospective, comparative clinical trial. Patients suffering from refractory glaucoma after failed surgeries and requiring a further glaucoma procedure including an aqueous shunt were enrolled in this study. The first group AGV included patients with an AGV. The second group eW-B included patients receiving an eyeWatch used in connection with a Baerveldt glaucoma implant. The primary outcome was the success rate, defined as an IOP≤16 mm Hg and reduction of >20% from baseline, and IOP≥5 mm Hg. Secondary outcomes were mean IOP, number of antiglaucoma medications, visual acuity, number and type of complications. RESULTS: Twenty-one patients were included. The mean follow-up time was 13.2±3.4 months. Mean IOP decreased from 24.8±9.0 mm Hg before surgery to 13.8±3.6 mm Hg at 12 months for group AGV, and 27.3±7.0 to 12.8±2.4 mm Hg for group eW-B, respectively (P<0.05). Mean number of glaucoma medications decreased from 3.0±0.7 before surgery to 0.3±0.7 at last control for group AGV, and 2.9±0.8 before surgery to 0.2±0.4 for group eW-B, respectively (P<0.05). The complete and overall success rates were 50% and 58% for group AGV, and 67% and 89% for group eW-B, respectively. CONCLUSIONS: The postoperative adjustability of the eyeWatch is believed to help with getting fewer complications and better IOP management whereas AGV cannot be adjusted postoperatively.

Initial Clinical Results of the eyeWatch: a New Adjustable Glaucoma Drainage Device Used in Refractory Glaucoma Surgery.

PRéCIS:: In this study, we report clinical results after implantation of an adjustable glaucoma drainage device. The intraocular pressure (IOP) profile was efficiently controlled postoperatively as the resistance to aqueous humor outflow was finely adjusted. PURPOSE: The main purpose of this study was to evaluate the safety and efficacy of the new adjustable glaucoma drainage device eyeWatch used in conjunction with a Baerveldt glaucoma implant in refractory glaucoma. PATIENTS AND METHODS: This was a multicentric, prospective, noncomparative clinical trial. Patients older than 18 years of age suffering from refractory glaucoma after failed surgeries, with IOP of ≥20 mm Hg, in whom a further glaucoma procedure using an aqueous shunt was planned, were enrolled in this study. The primary outcome was the success rate, defined as an IOP≤18 mm Hg and reduction of >20% from baseline, IOP≥6 mm Hg. Secondary outcomes were mean IOP, visual acuity, number of antiglaucoma medications, number, and type of complications. RESULTS: Fifteen patients were included. The mean follow-up time was 15.6±3.5 months. The mean baseline IOP decreased from 26.2±6.8 mm Hg before surgery to 11.9±2.8 mm Hg at 12 months (P<0.001). The mean number of glaucoma medications decreased from 3.0±0.7 before surgery to 0.8±0.9 at last visit (P<0.001). The success rate was 40% for complete success and 93% for overall success at last follow-up. Complication rate was 7%. CONCLUSIONS: The novel glaucoma device allows for perioperative and postoperative noninvasive adjustments of the resistance to aqueous humor outflow. This leads to better management of IOP during the early postoperative period, preventing ocular hypotony and eliminating the need for obstructive elements and reinterventions. The rate of complications was low, IOP was adequately controlled and lowered, with a substantial reduction in the number of antiglaucoma medication.

Type, severity, management and outcome of ocular and adnexal firework-related injuries: the Rotterdam experience.

PURPOSE: To study the type, severity, management and outcome of firework-related adnexal and ocular injuries during New Year's Eve festivities. METHODS: A retrospective analysis of 123 injured patients (143 eyes) treated at the Rotterdam Eye Hospital between 2009 and 2013. All ages were included and analysed according to age, gender, active participant or bystander, laterality, location, dimension and severity of injury. Outcome parameter was the final best-corrected visual acuity. RESULTS: The mean age was 22 ± 13 years with 87% males and 53% bystanders. 52% were ≤18 years. There was a higher number of female than male bystanders (63% versus 51%, p = 0.30). 50% of the eyes sustained mild, 13% moderate and 37% severe trauma. Adults suffered more from severe injuries compared to children (42% versus 31%). The most frequent intervention was gunpowder removal (20%), followed by traumatic cataract surgery (12%) and amniotic membrane grafting (8%). 76% of patients were followed over 1 year. At the end of follow-up, 88 (61.5%) eyes had recovered fully, while 55 (38.5%) eyes suffered from persistent complications with reduced vision ≤0.8 in 30% of injured eyes. 15 patients (12%, 10 adults, five children) were considered legally blind (vision ≤0.1). Three (2%) eyes were subject to evisceration. CONCLUSION: Every year, around New Year's Eve 30-45 victims were referred to the Rotterdam Eye Hospital; 50% sustained moderate-to-severe trauma. In severe firework injuries, patients required multiple treatments that may not prevent permanent blindness and/or functional/cosmetic disfigurement. The majority was bystander and younger than 18 years.

Long-term Follow-up of Canaliculotomies after Canaliculitis.

BACKGROUND: Canaliculitis is often misdiagnosed. There are several conservative and surgical treatment options. PATIENTS AND METHODS: Retrospective analysis of 14 canaliculotomies in 10 patients with canaliculitis. The overall length of the surgically induced opening was measured and compared to the corresponding untreated lacrimal punctae. Lacrimal duct concrements were liberated and sent for microbiological and histological analysis. Patient satisfaction and relief of symptoms were documented as well as clinical findings. RESULTS: Mean age was 59 ± 10 years (36 - 73 years) with balanced gender distribution. Mean follow-up time was 13 ± 8 months (4 - 27 months). Canaliculotomy was performed on 12 out of 14 inflamed canaliculi; in 2 cases, 3-snip punctoplasty was sufficient. The surgically induced length of the cuts was 1.7 ± 0.9 mm (0.4 - 3.7 mm). In 13 out of 14 cases, macroscopic concrements were found intraoperatively and actinomyces was verified histologically. Nine patients were free of symptoms postoperatively, and one patient manifested markedly less epiphora. CONCLUSIONS: The canaliculi remained open within the long-term follow-up period without any drawbacks to the lacrimal outflow. No recurrent infections were seen.

Eyelid Reconstruction: Pediculated versus Non-Pediculated.

BACKGROUND: To compare the functional and cosmetic outcome of pediculated versus free anterior and posterior lamella reconstruction after large eyelid defects due to malignancy excision. PATIENTS AND METHODS: A retrospective study over 2 years with 12 patients matching the criterion of pediculated versus non-pediculated transplants out of a cohort of 124 tumor excisions. The mean age was 76 ± 8 years of the 7 male and 5 female patients. In the majority of cases, more than half of the eyelid was excised. The posterior lamella was always reconstructed with tarsal tissue, and the anterior lamella mostly with an upper eyelid skin graft. The postoperative follow-up time was between 2 months and 1 year. RESULTS: Nodular basal cell carcinoma was the prevailing histology (6 patients). The reconstruction techniques included a Hughes procedure (four patients) or a free tarsal graft with a pediculated skin flap (four patients), respectively. In the remaining four patients, a combination of pediculated/free anterior AND posterior lamellae was performed. Four patients had a one-stage and eight patients a 2nd stage procedure with a mean time until tarsoconjunctival flap reopening of 16 ± 2 days. CONCLUSIONS: No difference was found in the final functional outcome in pediculted versus free grafts. The cosmetic result was better in anterior lamella reconstructions with a pediculated flap, which usually allows a one-stage procedure. The 2nd stage procedure could be performed after 2 weeks without any complications.

Correlation Between Dynamic Contour Tonometry, Uncorrected and Corrected Goldmann Applanation Tonometry, and Stage of Glaucoma.

Importance: Accurate determination of intraocular pressure (IOP) is crucial for the diagnosis and management of glaucoma. Objective clinical evaluation of the correction equations for Goldmann applanation tonometry (GAT) is lacking. Objectives: To investigate the difference between corrected and conventional GAT and Pascal dynamic contour tonometry (DCT) measurements, as well as the correlation between discordant IOP values and stage of glaucoma. Design, Setting, and Participants: This prospective cross-sectional case series was conducted at the Department of Ophthalmology, University Hospital Zurich, and Talacker Eye Center between July 1, 2011, and May 31, 2016, among 112 white patients with glaucoma. Interventions: Intraocular pressure measurements were performed with GAT and DCT in a randomized order. Goldmann applanation tonometry measurements were modified with 5 correction equations. Main Outcomes and Measures: The primary end point was degree of concordance between corrected or uncorrected GAT and DCT measurements. The secondary end point was association between discordant IOP measurements and the stage of glaucoma, as assessed by the Glaucoma Severity Score. Results: Among the 112 patients (67 women and 45 men; mean [SD] age, 66.3 [13.1] years), 63 of the eyes in the study (56.3%) were left eyes and 85 patients (75.9%) were taking ocular antihypertensive medications. Mean (SD) IOP was 20.3 (4.5) mm Hg (95% CI, 19.4-21.1) as measured by DCT and 17.0 [4.1] mm Hg (95% CI, 16.3-17.8) as measured by GAT. The mean (SD) discordance between DCT and GAT measurements was -3.3 (2.0) mm Hg (95% CI, 2.9-3.6). The 5 corrected GAT values ranged from -2.7 to -5.4 mm Hg compared with DCT. The mean (SD) result of the Dresdner correction formula (17.6 [4.1] mm Hg) was closer to the DCT measurement than the original GAT measurement. The mean (SD) Glaucoma Severity Score was 4.7 (3.4) (95% CI, 4.1-5.4). The uncorrected discordance IOPDCT - IOPGAT showed a positive correlation with the Glaucoma Severity Score (rs = 0.33; P < .001) and a negative correlation with central corneal thickness (rs = -0.22; P = .02). Conclusions and Relevance: In comparison with DCT measurements, these data suggest that GAT values are significantly discordant in eyes with thin corneas and advanced glaucoma. Application of GAT-based correction formulas involves a possible risk of creating an even greater number of unpredictable measurement errors. Hence, we advise with caution, especially pertaining to eyes with thin corneas, to not place reliance on GAT readings, and abandon any correction formula. Trial Registration: clinicaltrials.gov Identifier: NCT01474070.

Hand-held dynamic contour tonometry.

PURPOSE: We present a prototype of the hand-held dynamic contour tonometer (HH-DCT) and prospectively compare this HH-DCT with the well-established Perkins applanation tonometer (PAT) and the TonoPenXL (TPXL). METHODS: In a prospective, single-centre, randomized study, intraocular pressure (IOP) readings were taken in random order using HH-DCT, PAT and TPXL tonometers. Intra-observer variability was calculated for each observer and compared between three experienced ophthalmologists and an inexperienced medical student. RESULTS: Ninety-two corneas of 92 healthy participants were enrolled. IOP [mean mmHg ± standard deviation (SD)] as measured by HH-DCT was 16.97 ± 2.71, by PAT 13.98 ± 2.52 and by TPXL 13.34 ± 2.68. The range of three consecutive IOP readings differed significantly between the devices [p < 0.001; mean range: 1.45 ± 1.07 (HH-DCT), 1.87 ± 0.97 (PAT) and 2.08 ± 1.77 (TPXL)]. There was no difference of the range in all devices between the ophthalmologists and the medical student (HH-DCT p = 0.68, PAT p = 0.54, TPXL p = 0.48). CONCLUSION: IOP readings measured by HH-DCT are significantly higher than by PAT and TPXL. The differences of IOP measurements are in good accordance with previous studies using the slit-lamp-mounted DCT (SL-DCT) and Goldmann Applanation Tonometry, where SL-DCT readings were 1-3.2 mmHg higher. HH-DCT seems to give more constant results, which can be seen in the lower intra-observer variability compared to PAT and TPXL.

Tonometry through the ages.

The definition of glaucoma has changed over the decades from a simple ocular pressure disease to a systemic disorder of multivariate etiology. Glaucoma may be defined for the individual eye as a chronic ocular disease with various underlying pathophysiologic disorders. However, elevated intraocular pressure (IOP) is still the most important risk factor for an untreated glaucomatous eye to progress to a more severe stage of the disease. As the main risk factor within therapeutic reach, IOP and its appropriate measurement deserve our ongoing interest. Not only has our understanding of glaucoma changed but also our approach to the measurement of the IOP. In this article we focus our attention on the various developments in tonometry from the simple force-tonometers of the late 19th century to the high-technology pressure tonometers that were recently introduced for clinical use.

Effect of riboflavin-UVA-induced collagen cross-linking on intraocular pressure measurement.

PURPOSE: Corneal collagen cross-linking (CCL) with riboflavin and ultraviolet A irradiation has recently been introduced for treatment of corneal ectasia. Yet a CCL-induced increase in corneal rigidity may interfere with intraocular pressure (IOP) measurements. In an investigation of the effect of CCL on the accuracy of IOP measurements, IOP readings before and after CCL were compared. METHODS: Ten human eye bank corneas were de-epithelialized and mounted on an artificial anterior chamber. The hydrostatically controlled reference pressure in the chamber was adjusted from 10 to 40 mm Hg in 5-mm Hg steps. IOP was measured by Goldmann applanation tonometry (GAT; Haag Streit, Könitz, Switzerland), dynamic contour tonometry (DCT; Pascal tonometer; Ziemer Ophthalmics, Port, Switzerland), and the TonoPen XL (TP; Tono-Pen XL, Medtronic, Jacksonville, FL) before and after CCL, which was performed with a 0.1% riboflavin solution and 30 minutes of UVA irradiation. RESULTS: Before CCL, GAT, and DCT readings showed an excellent concordance with the manometric reference pressure, whereas TP overestimated the true IOP. After CCL, the reliability of IOP readings decreased with all three tonometers. This decrease resulted in a slight overestimation of mean IOP, but there were also some potentially dangerous underestimations in some individual corneas. The mean (+/-SD) difference between IOP readings after and before CCL was +1.8 (3.5) mm Hg for DCT, +2.9 (6.1) mm Hg for GAT, and +3.1 (8.3) mm Hg for TP (P

Prevalence of plateau iris syndrome in young patients with recurrent angle closure.

BACKGROUND: To assess and describe the prevalence and clinical features associated with plateau iris syndrome (PIS) in young individuals with recurrent angle closure despite initial therapy. METHODS: Chart review of 137 relatively young individuals (aged < 60 years) with symptoms of angle closure between 1995 and 2005. A follow-up period of 36 months after initial presentation was retrospectively analysed. Seventy-six patients with recurrent angle closure symptoms were clinically reviewed using gonioscopy and ultrasound biomicroscopy. RESULTS: Based on chart analysis, 30 of 137 individuals were diagnosed with PIS (22%). After clinical review, 34 additional patients suffered from PIS as the underlying cause for persistent angle closure symptoms. The prevalence of PIS in our patient population with recurrent angle closure symptoms in spite of initial iridotomy or iridectomy was 54%. CONCLUSION: Among angle closure in young individuals, PIS is not uncommon. The causative mechanism of PIS in young individuals is peripheral iris block, rather than pupillary block which is more often prevalent in older patients. For proper diagnosis and therapy, ultrasound biomicroscopy and gonioscopy should be performed on every young individual with angle closure symptoms.

Dynamic contour tonometry: principle and use.

Interindividual variability of central corneal thickness has been found to be a source of error for conventional Goldmann applanation tonometry. The dynamic contour tonometer represents a potentially new technology for non-invasive and direct intraocular pressure (IOP) measurement, and has been proposed to accurately measure the true IOP irrespective of the corneal thickness. It is based on the principle that when the tip of the device exactly matches the contour of the cornea, the pressure measured by a transducer placed on its tip is an accurate indicator of the true IOP. This device is also capable of measuring the ocular pulse amplitude, a variable that has controversial significance in the diagnosis and management of glaucoma. Even though this technique seems to be very promising, further studies are required to conclusively determine the effectiveness of the dynamic contour tonometer in patients having an abnormal or irregular corneal contour.

Intraocular pressure and ocular pulse amplitude comparisons in different types of glaucoma using dynamic contour tonometry.

PURPOSE: To compare the intraocular pressures (IOP) and ocular pulse amplitudes (OPA) in patients with different types of glaucoma, ocular hypertension (OHT), and normal controls (NC) using dynamic contour tonometry (DCT) and the goldmann applanation tonometry (GAT). METHODS: 906 eyes of 501 adult patients in the following five groups were included in this cross-sectional study: primary open angle glaucoma (POAG), normal tension glaucoma (NTG), Pseudoexfoliative Glaucoma (PXG), OHT, and NC. The following tests were performed simultaneously during a single visit: IOP using DCT and GAT; OPA using DCT and central corneal thickness (CCT) using ultrasound pachymetry. Mixed effects regression models were used to compare the DCT and GAT IOP measurements in the five groups; the effect of CCT on IOP and the relationship between OPA and IOP within each group. RESULTS: DCT consistently had higher IOP values than GAT in POAG, PXG, NTG, and controls (p < 0.001) but not in OHT (p = 0.84). DCT IOP did not change while GAT IOP showed a non-significant increase (p = 0.09) with increased corneal thickness in each group. OPA was found to be highest in OHT (3.61 mmHg) and lowest in the control group (2.86 mmHg) and significantly increased with IOP in all groups. CONCLUSIONS: DCT measures an IOP that is significantly higher than GAT IOP in glaucoma and control subjects but not in ocular hypertensives. Furthermore, the DCT may measure an IOP that is independent of the CCT, which may not be true for the GAT, which increases with the CCT. OPA was highest in OHT and may be affected by the IOP.

A novel PITX2 mutation and a polymorphism in a 5-generation family with Axenfeld-Rieger anomaly and coexisting Fuchs' endothelial dystrophy.

PURPOSE: To investigate the clinical and genetic appearance of Axenfeld-Rieger anomaly or syndrome (ARAS) and Fuchs' endothelial dystrophy (FED) in a 5-generation pedigree coexpressing both pathologic features in a large number of family members. DESIGN: Observational case-control and DNA linkage and screening study. PARTICIPANTS: Of 114 family members, 50 underwent clinical investigation and DNA analysis between July 2001 and March 2004. METHODS: Linkage at the PITX2 locus was demonstrated using a number of microsatellites mapping to the critical region 4q25 to 4q26. The PITX2 gene was subsequently screened for mutations in all investigated family members. MAIN OUTCOME MEASURE: Linkage of the ARAS and FED phenotype and mutation detection in the PITX2 gene. RESULTS: Twenty-seven patients were identified as being affected by ARAS. Fuchs' endothelial dystrophy was found in 19 patients. Fifteen patients presented both kinds of anomaly. Deoxyribonucleic acid sequencing revealed 2 heteroallelic DNA variants that segregated together (on the same allele) and were present in all severely affected ARAS individuals. The first variant, g.20913G>T, assumed to be the causative mutation for ARAS, causes amino acid substitution at codon 137 (G137V). A statistically significant 2-point logarithm of the odds score of 4.06 was obtained with marker D4S406. The second variant is likely a polymorphism in the intron between exons 2 and 3 (IVS2+8delCinsGTT) and was detected in heterozygous form in 20% of control individuals. CONCLUSION: This gene analysis revealed a novel PITX2 mutation and a polymorphism in a family with ARAS. Whether FED, also manifested in the severely affected individuals, is due to a different but cosegregating gene is to be determined.

Correlation between intraocular pressure, central corneal thickness, stage of glaucoma, and demographic patient data: prospective analysis of biophysical parameters in tertiary glaucoma practice populations.

PURPOSE: To determine the correlation of central corneal thickness (CCT) to Goldmann applanation tonometry (GAT) and dynamic contour tonometry (DCT, PASCAL), and to glaucoma stage as assessed by cup-to-disc ratio (CDR). DESIGN: Prospective, cross-sectional tricenter observation study. PATIENTS AND METHODS: From three glaucoma specialty practices a sample of 406 independent eyes was included. After ultrasound pachymetry, intraocular pressure was measured using PASCAL and Goldmann applanation tonometry and cup-to-disc ration was reassessed. Demographic data were included in the multivariate analysis. RESULTS: Mean corneal thickness was 540 microm. African Americans and normal-tension glaucoma patients showed the lowest values (518 microm and 522 microm, respectively). These values were significantly thinner than the central corneal thickness of Caucasians (549 microm) and ocular hypertensives (564 microm). Intraocular pressure assessed by Goldmann applanation tonometry shows a significant correlation with central corneal thickness (r = 0.068, P < 0.001), whereas PASCAL is not significantly associated with central corneal thickness (r < 0.001, P = 0.997). Increased IOP is significantly correlated with large ocular pulse amplitudes (r = 0.13, P < 0.001), which is predominantly seen in ocular hypertensives. A significant negative correlation was detected between cup-to-disc ratio and central corneal thickness (r = 0.102, P < 0.001). CONCLUSION: Glaucoma patients with thin central corneal thickness are more likely to be found at an advanced stage of the disease and among those with normal-tension glaucoma and black African ancestry. Underestimation of intraocular pressure by Goldmann applanation tonometry could be one causative factor.