Diagnosis Of Angle-closure Glaucoma Research Articles

Proportion of Angle Closure Glaucoma in Tamale, Ghana.

In the largest clinic-based study to date, our review of 588 patients presenting with glaucoma in Northern Ghana revealed 36% of these had primary angle closure glaucoma. Glaucoma is the second leading cause of blindness worldwide. In Africa, glaucoma is an established public health problem, and primary angle-closure glaucoma (PACG) is not commonly discussed. Recognizing it is important because of its negative impact on visual morbidity, and also because its treatment is different from primary open angle glaucoma (POAG). In response to the observation of many PACG cases at the Northern Community Eye Hospital in Tamale, Ghana, we investigated the proportion of those attending with a first diagnosis of glaucoma who had PACG. Using the electronic records, we identified 976 patients who attended with a first diagnosis of glaucoma between January 2021 and October 2022. Of these, 588 met the inclusion criterion of a clear glaucoma subtype diagnosis. Of these 316 (53.7%) had POAG, 210 (35.7%) PACG, and 62 (10.5%) secondary glaucoma. Thus, over a third of presenting glaucomas had PACG. This study highlights that PACG is present in about a third of patients presenting to our clinic in North Ghana . Our study demonstrates the importance of a clear diagnostic pathway including gonioscopy in the assessment of glaucoma patients and the consideration of wider training on angle closure glaucoma diagnosis and management.

Technologies for the diagnosis of angle closure glaucoma (ACE): protocol of a prospective, multicentre, cross-sectional diagnostic study

IntroductionAngle-closure is responsible for half of all glaucoma blindness globally. Patients with suspected glaucoma require assessment of the drainage angle by an experienced clinician. The goal of this study is...

Outcomes of Filtering Surgery Versus Clear Lens Extraction in Young Patients With Angle-Closure Glaucoma

PurposeTo compare the effect of filtering surgery versus clear lens extraction in young patients with medically uncontrolled angle-closure glaucoma (ACG). DesignRetrospective, non-randomized, comparative, interventional study. MethodsWe reviewed the medical charts of patients with the following scenarios: (1) age ≤ 40 years, (2) diagnosis of ACG without cataract, including primary angle-closure glaucoma (PACG), nanophthalmic ACG and ACG combined with retinal dystrophies, (3) ACG undergoing filtering surgery or clear lens extraction. The main outcomes including intraocular pressure (IOP), number of medications, best-corrected visual acuity, and severe complications were extracted at the postoperative early (within 1 week) and late stage (>3 months) follow-up. ResultsData from 160 eyes of 130 young patients with ACG were available. Eyes with 76 PACG, 12 nanophthalmic ACG, and 26 ACG with retinal diseases underwent filtering surgery, while eyes with 22 PACG, 12 nanophthalmic ACG, and 12 ACG with retinal diseases received clear lens extraction. Overall, filtering surgery and clear lens extraction resulted in significant but comparable IOP and drug reductions at the postoperative late stage in each ACG subgroup, with similar complete success rates between two treatments (all P >.05). Regarding the safety, filtering surgery and patients with retinal diseases were independent factors associated with postoperative malignant glaucoma (P <.05 in both multivariable logistic regression models). ConclusionsThis study highlights that the efficacy of clear lens extraction is comparable to that of filtering surgery in medically uncontrolled young ACG, but clear lens extraction is safer, especially for young ACG comorbid with retinal diseases.

Comparison study for the proportion of underdiagnosed zonulopathy in angle closure glaucoma

Objective: To analyze the proportion and clinical characteristics of underdiagnosed zonulopathy in angle closure glaucoma (ACG) patients and to explore the related risk factors. Methods: Case-control study. Continuous cases of ACG patients who underwent phacoemulsification combined with intraocular lens implantation and goniosynechialysis surgery [ACG group, including acute angle closure glaucoma (AACG) and chronic angle closure glaucoma (CACG)] from November 1, 2020 to October 31, 2021 and age-related cataract patients who underwent phacoemulsification combined with intraocular lens implantation surgery in the same period (control group) were included. The diagnosis of zonulopathy was determined according to the intraoperative signs such as wrinkles of the anterior capsule during continuous circular capsulorhexis. The proportion of zonulopathy, preoperative diagnosis rate of zonulopathy, demographic characteristics, anterior chamber depth (ACD), axis length, difference of ACD in both eyes (ACD of the contralateral eye minus ACD of the operated eye) were compared between the two groups. The related risk factors were explored. The paired t-test (comparison between two groups of normally distributed data), non-parametric test (comparison between two groups of non-normally distributed data), Chi-square test (categorical variables), univariate and multivariate logistic regression analysis were used. Results: There were 104 ACG patients (104 eyes), including 63 AACG patients (63 eyes) and 41 CACG patients (41 eyes), and 117 controls (117 eyes). There was no significant difference in age (P=0.29) and gender (P=0.07) between the two groups. The ACG group had shallower anterior chamber (P<0.001), shorter axial length (P<0.001) and more ACD difference in both eyes (P<0.001). In the ACG group, the proportion of zonulopathy was 46.2% (48/104), which was significantly higher than that (6.0%, 7/117) in the control group (P<0.001). In the control group, only zonular laxity was found, while in the ACG group, besides the predominant zonular laxity (68.8%, 33/48), there was zonular dehiscence (31.3%, 15/48). The eyes with AACG (57.1%, 36/63) had a higher proportion of zonulopathy than those with CACG (29.3%, 12/41) (P=0.006). In the ACG group, only 14 cases (29.8%) were diagnosed preoperatively according to slit lamp examination and/or ultrasound biomicroscopy. The proportion of underdiagnosed zonulopathy was 70.8% in the ACG group (34/48). A smaller ACD was found to be related to the zonulopathy in the ACG group. All AACG cases with an ACD ≤2.0 mm and CACG cases with an ACD ≤1.9 mm had zonulopathy. Multivariate logistic regression showed that the ACD difference in both eyes (P=0.025) and the diagnosis of ACG (AACG vs. cataract, P<0.001; CACG vs. cataract, P=0.023) were independent risk factors associated with zonulopathy. Conclusions: The proportion of underdiagnosed zonulopathy among ACG patients is high. Better preoperative diagnostic methods for zonulopathy are needed. Zonulopathy is common in ACG patients, especially in AACG patients, suggesting that zonulopathy may be related to the pathogenesis of ACG. The shallower the ACD, the riskier the zonulopathy. ACD differences between two eyes and ACG types (including AACG and CACG) were related risk factors of zonulopathy.(This article was published ahead of print on the Online-First Publishing Platform for Excellent Scientific Researches of Chinese Medical Association Publishing House on March 11, 2022).

State of the art in acute glaucoma attack predisposition issue

Angle-closure glaucoma diagnosis verification is based on biometric indicators and computer tomography data of the anterior segment of the eye. However, not every patient with a narrow angle and a shellow anterior chamber develops an acute attack. The review summarizes the literature data on risk factors for an acute glaucoma attack and lists additional parameters to be considered when examining patients with angle-closure glaucoma to identify a predisposition to an acute glaucoma attack.

Multiview Volume and Temporal Difference Network for Angle-Closure Glaucoma Screening from AS-OCT Videos

Background. Precise and comprehensive characterizations from anterior segment optical coherence tomography (AS-OCT) are of great importance in facilitating the diagnosis of angle-closure glaucoma. Existing automated analysis methods focus on analyzing structural properties identified from the single AS-OCT image, which is limited to comprehensively representing the status of the anterior chamber angle (ACA). Dynamic iris changes are evidenced as a risk factor in primary angle-closure glaucoma. Method. In this work, we focus on detecting the ACA status from AS-OCT videos, which are captured in a dark-bright-dark changing environment. We first propose a multiview volume and temporal difference network (MT-net). Our method integrates the spatial structural information from multiple views of AS-OCT videos and utilizes temporal dynamics of iris regions simultaneously based on image difference. Moreover, to reduce the video jitter caused by eye movement, we employ preprocessing to align the corneal part between video frames. The regions of interest (ROIs) in appearance and dynamics are also automatically detected to intensify the related informative features. Results. In this work, we employ two AS-OCT video datasets captured by two different devices to evaluate the performance, which includes a total of 342 AS-OCT videos. For the Casia dataset, the classification accuracy for our MT-net is 0.866 with a sensitivity of 0.857 and a specificity of 0.875, which achieves superior performance compared with the results of the algorithms based on AS-OCT images with an obvious gap. For the Zeiss AS-OCT video dataset, our method also gets better performance against the methods based on AS-OCT images with a classification accuracy of 0.833, a sensitivity of 0.860, and a specificity of 0.800. Conclusions. The AS-OCT videos captured under changing environments can be a comprehended means for angle-closure classification. The effectiveness of our proposed MT-net is proved by two datasets from different manufacturers

Identification of Peripheral Anterior Synechia by Corneal Deformation Using Air-Puff Dynamic Anterior Segment Optical Coherence Tomography.

Indentation gonioscopy is commonly used in the clinic to evaluate peripheral anterior synechia (PAS) of angle closure glaucoma (ACG). The examination requires contacting with the cornea, resulting in an uncomfortable feeling for patients, and it only provides qualitative outcomes which may be affected by subjective judgment of the clinicians. Previous studies had reported to identify the presence of PAS by measuring the changes of morphological parameters of the anterior chamber angle (ACA) under the pupillary light reflex, by anterior segment optical coherence tomography (AS-OCT). However, this method was invalid for some subjects who had low sensitiveness to light. This article describes an air-puff dynamic anterior segment optical coherence tomography (DAS-OCT) system that can evaluate the presence of PAS in a non-contact approach. The peripheral cornea is deformed by an air puff jetted from the DAS-OCT, causing a transfer of force to the ACA, just as how indentation gonioscopy works. The dynamic changes of the ACA before and after the air puff are recorded by OCT. Ten eyes of normal subjects were enrolled in this study to validate the repeatability and availability of the measurements. Then, ten samples of the ACA from five subjects with ACG were recruited and were assigned into two groups, the non PAS group (NPAS) and PAS group, according to the results of gonioscopy. The ACA structural parameters including the angle opening distance at 750 μm to the scleral spur (AOD750) and the trabecular-iris space area at 750 μm anterior to the scleral spur (TISA750) were then calculated automatically by a custom-written algorithm. The intraclass correlation coefficient (ICC) of measured parameters was all above 0.85 for normal subjects, exhibiting good repeatability. For patients, both parameters showed significant differences between the two groups after the air puff, while no differences were observed before the air puff. AOD750dif and TISA750dif between two groups showed more significant differences, indicating that they could be used as indicators to identify the presence of PAS. In conclusion, the DAS-OCT system proposed in this study is demonstrated effective to identify the presence of PAS by measuring the changes of the ACA via a noncontact approach. It shows great potential for applications in guidance for diagnosis of angle closure glaucoma.

Choroidal Metastatic Carcinoma Accompanied With Sjögren Syndrome Initially Presenting as Acute Glaucoma With Angle Closure: Case Report

BackgroundTo report a case of choroidal metastatic carcinoma accompanied by Sjögren syndrome (SS) initially presenting as acute glaucoma with angle closure.Case PresentationA 47-year-old woman complaining about swelling pain and blurred vision in the right eye for 3 days had a notable previous history of dry eyes, dry mouth, and joint pain. In another clinic, she was misdiagnosed as having acute glaucoma with angle closure, but she had poor response to eye drops and intravenous drip of mannitol for controlling intraocular pressure. The intraocular pressure in the right eye was 49 mm Hg, yet with clear cornea, shallow peripheral anterior chamber depth with 1/4 cornea thickness and fixed and dilated pupil. Macular folds were noted through a 90-D lens via slit lamp. Therefore, the diagnosis of secondary glaucoma was considered. Further examinations were conducted. Ultrawide-field fundus image showed retinal detachment with choroidal detachment in the right eye with suspected solid occupation of choroid metastatic cancer. B-scan ultrasound showed an elevated mass in the posterior pole of the ocular wall. The patient showed very good response to local corticosteroid eye drops after 3 days with deepening of the anterior chamber and significant decline of intraocular pressure. The brain, ocular magnetic resonance imaging, and lung computed tomography with enhancement showed lung cancer and choroidal metastatic carcinoma. Immunological abnormalities and symptoms supported the diagnosis of SS. After 1-month systematic chemotherapy and local–regional radiotherapy, retinal and choroidal detachment was restored with a stable intraocular pressure.ConclusionThe ophthalmologist should pay attention to differential diagnosis of angle-closure glaucoma from secondary glaucoma in cases with choroidal–retinal detachment or macular folds, which could be an ocular manifestation of choroidal metastatic carcinoma or SS in rare condition.

Etiologies and clinical characteristics of young patients with angle-closure glaucoma: a 15-year single-center retrospective study

PurposeTo investigate the etiologies and the clinical characteristics of angle-closure glaucoma (ACG) patients younger than 40 years old in Chinese.MethodsInpatients with diagnosis of ACG and diagnosed age younger than or equal to 40 years old, who were admitted in Eye, Ear, Nose, and Throat Hospital Fudan University from 2002 to 2017, were included in this retrospective non-comparative case series. The underlying causes and clinical features for all the patients were analyzed by comprehensive review of medical charts.ResultsA total of 298 patients (463 eyes) met the criteria, including 153 females (51.3%) and 145 males (48.7%); the mean age was 25.6 ± 13.0 years. Primary angle-closure glaucoma (PACG), uveitis, and anterior segment dysgenesis (ASD) were the top three etiologies in our patients, which accounted for 32.6%, 20.3%, and 15.1% of the total patients respectively. PACG mainly occurs after 30 years of age and ASD is the top reason of ACG in patients younger than 20 years old. Other known etiologies include iridocorneal endothelial syndrome, neovascular glaucoma, nanophthalmos, retinitis pigmentosa, spherophakia, bestrophinopathy, persistent fetal vasculature, iridociliary cysts, congenital retinoschisis, Marfan’s syndrome, retinopathy of prematurity, familial exudative vitreoretinopathy, congenital retinal folds, Coat’s disease, and neurofibromatosis.ConclusionsWe described the uncommon presentation of ACG in Chinese young patients. Although unusual, most of the etiologies could be identified. Therefore, more careful and comprehensive examinations are needed for early detection and timely treatment for young ACG patients.

An insight into Principle and Practice of Anterior Segment Optical Coherence Tomography

Proper visualization of the eye structures is the hallmark of diagnosis in eye diseases. With advent of newer techniques and instruments, the significance of anterior segment eye structures is further elaborated. This article explores the basic working principle of optical coherence tomography (OCT) and also provides a list of commonly available instruments and their advantages over one another. It then sheds light upon the use of anterior segment OCT in the observation of cornea, conjunctiva, lacrimal gland and other anatomic structures of eye within the living subject. Anterior segment OCT is also helpful in the demonstration of dynamics involving aqueous flow system. The application of this advanced technique in diagnosis of dry eye disease, keratoconus, anterior segment eye tumors and other diseases is also explained. The examination of normal cornea along with all its layers is possible with anterior segment OCT and it can also point out any abnormality in corneal epithelium, edema or any other change that may occur after intra ocular lens placement or corneal transplantation. Anterior chamber angle measurement is an essential step in the diagnosis of angle closure glaucoma and quite accurate results are provided by this technique. The data was searched from PubMed and Google Scholar, from the articles published during 2014 and 2020, using the keywords “optical coherence tomography”, “glaucoma” and “anterior segment of eye”. A few of the limitations of OCT are also discussed along with the future perspectives of this powerful instrument. Keywords: Anterior Eye Segment; Optical Coherence Tomography; Glaucoma; Anterior Chamber Angle.

Outcome Following Laser Peripheral Iridotomy and Predictors of Future Lens Extraction.

To examine the outcome of laser peripheral iridotomy (LPI) for primary angle closure and determine predictors of future lens extraction (LE). A retrospective chart review of 218 eyes from 128 consecutive patients undergoing LPI between 2010 and 2012 at a university hospital. Baseline factors including age, peak intraocular pressure (IOP) before LPI, diagnosis (primary angle closure suspect, primary angle closure, primary angle closure glaucoma), and acute or non-acute presentation were recorded. Patients were followed for 3.7±1.6 years. Kaplan-Meier curves were constructed to examine survival times to LE and Cox proportional hazard regression was used to identify factors associated with LE. In total, 91 of 218 eyes (41.7%) initially treated with LPI had LE during follow-up. For eyes with non-acute presentation, 12%, 25%, and 32% had LE at 1, 2, and 3 years, respectively. For eyes with acute presentation, 27%, 42%, and 50% had LE at 1, 2, and 3 years. In univariable analysis, older age, higher IOP, worse visual field, and primary angle closure glaucoma diagnosis were associated with LE, with older age and higher IOP remaining significant in multivariable analysis. There was a 1.09-fold increased odds of LE for each year older at baseline and each 1 mm Hg higher IOP was associated with a 1.08-fold increased odds of LE. A large proportion of patients with angle closure treated with LPI went on to require LE. Patients with features associated with higher odds of LE might be considered for LE as a primary procedure.

OCT in Prone Position: A New Approach to Glaucoma

Glaucoma is characterized by a progressive loss of ganglion cells and of the retinal nerve fiber layer (RNFL), mostly related to an intraocular pressure higher than normal. According to the format of the camerular sinus, Glaucoma is divided in Open-Angle and Angle-Closure. Classically, it is known that angle-closure glaucoma is more aggressive than Open-angle Glaucoma for reaching extremely high intraocular pressure levels. The technique that we created is an improvement of the technique idealized and knew as a prone position provocative test for angle-closure glaucoma. As OCT did not exist at that time, the identification of the patient with angle-closure glaucoma was done by comparing the IOP measurements before and after a time with the patient in prone position. The objective of this study is to present a new diagnostic approach using an existing technology: the optical coherence tomography (OCT). The innovation lies in how to use the OCT device. We have developed a theoretical system of identification of the camerular sinus type which can improve the diagnosis of angle-closure glaucoma. The improved system for optic coherence tomography, object of this article, consists of an apparatus for performing OCT examination of the anterior segment in the lying position.

Complex wavelet based quality assessment for AS-OCT images with application to Angle Closure Glaucoma diagnosis

Background and objectivesAngle closure disease in the eye can be detected using time-domain Anterior Segment Optical Coherence Tomography (AS-OCT). The Anterior Chamber (AC) characteristics can be quantified from AS-OCT image, which is dependent on the image quality at the image acquisition stage. To date, to the best of our knowledge there are no objective or automated subjective measurements to assess the quality of AS-OCT images. MethodsTo address AS-OCT image quality assessment issue, we define a method for objective assessment of AS-OCT images using complex wavelet based local binary pattern features. These features are pooled using the Naïve Bayes classifier to obtain the final quality parameter. To evaluate the proposed method, a subjective assessment has been performed by clinical AS-OCT experts, who graded the quality of AS-OCT images on a scale of good, fair, and poor. This was done based on the ability to identify the AC structures including the position of the scleral spur. ResultsWe compared the results of the proposed objective assessment with the subjective assessments. From this comparison, it is validated that the proposed objective assessment has the ability of differentiating the good and fair quality AS-OCT images for glaucoma diagnosis from the poor quality AS-OCT images. ConclusionsThis proposed algorithm is an automated approach to evaluate the AS-OCT images with the intention for collecting of high quality data for further medical diagnosis. Our proposed quality index has the ability of automatic objective and quantitative assessment of AS-OCT image quality and this quality index is similar to glaucoma specialist.

English

AIM: To report an atypical and misdiagnosed case of optic neuritis in a young female. METHOD: 26 year healthy female was referred to the Regional Institute of Ophthalmology, Amritsar with the diagnosis of angle closure glaucoma both eyes. Patient was on 2% pilocarpine eye drops q.i.d and tablet acetazolamide 250 mg BD. On examination, visual acuity was 2/60 OD and 1/60 OS. Near vision was 6/36 OU. There was no circumcorneal congestion OU, no corneal edema OU, though anterior chamber was shallow OS >OD with pin pointed non-reacting pupil OU. IOP 14.6mm Hg OD and17.3mm Hg OS. Gonioscopically open angle grade 2. IOP and gonioscopy were repeated after pupil dilatation with tropicamide, findings were consistent with the previous ones. Fundoscopy showed bilateral disc edema with hyperemia and normal foveal reflex. Color vision was defective .Low vision prevented a conclusive perimetry. ONTT protocol was given, on the basis of decreased visual acuity, abnormal color vision, headache, disc changes, open angle and a normal MRI. Patient’s vision improved to 6/6 OD 6/9 OS in thirteen days. CONCLUSIONS: Bilateral optic neuritis is rare and an atypical presentation can be misdiagnosed as angle closure glaucoma in presence of severe headache, OU visual loss and shallow anterior chamber.

Anterior chamber angle evaluation with fourier-domain optical coherence tomography.

New advances in anterior segment optical coherence tomography (OCT) technology development allow visualizing the anterior chamber angle of the eye with high speed and high resolution. Fourier-domain (FD) OCT instruments working at 840 nm can reliably identify fine angle structures such as the Schwalbe's line. This paper demonstrates quantitative angle assessment with 840 nm FD-OCT and provides diagnostic cutoff values for occludable angle detection. This is useful for angle closure glaucoma diagnosis and management. Moreover, 840 nm FD-OCT is a useful tool for postsurgical evaluation in glaucoma patients.

Hospital Episode Statistics and changing trends in glaucoma surgery

A number of authors have documented the decrease in the rate of glaucoma drainage surgery, felt to be owing to increased medical therapy options. There has also been an increase in cataract extraction. The aim of this study was, using the NHS Hospital Episode Statistics (HES), to attempt to confirm these trends and to examine the possibility that these trends are not necessarily independent. The HES was accessed for the main glaucoma procedures between 1998 and 2004 and for cataract operations performed over the same time period. Diagnostic data were also extracted from the HES data for glaucoma. Figures for the changes in glaucoma medications were obtained from pharmaceutical data. Over the period that the data are available, trabeculectomy numbers have reduced by 51%, laser trabeculoplasty by 60%, and laser peripheral iridectomy (PI) by 30%. Cataract extractions have increased by 52%. Medical treatments, especially prostaglandin use, have increased. The number of admissions for acute glaucoma did not increase. The figures indicated a decrease in glaucoma drainage surgery and an increase in cataract extraction-consistent with other studies. More surprisingly, there was no increase in diagnosis of angle closure glaucoma or laser PIs within the figures and we suggest this may in part be related to the increase in cataract extraction. We speculate that this may also partly be responsible for the reduction in trabeculectomies. Although the HES data are a potentially rich source of information, there are potential inaccuracies in the data, which means interpretations must be made with caution.

Long term results of glaucoma surgery among participants in an east African population survey

AIMTo evaluate the long term results of glaucoma surgery among people in East Africa.METHODSParticipants in a population based survey of eye disease prevalence were offered glaucoma surgery using standardised criteria....

Suprachoroidal Hemorrhage after Molteno Implantation

The objective of this study is to identify the rate and the associated risk factors for suprachoroidal hemorrhage (SCH) after Molteno drain implantation. Data from the Molteno pilot study and single versus double-plate Molteno study were reviewed retrospectively for the occurrence of SCH. Follow-up intervals, demographic variables, ocular data, and medical history were collected. SCH occurred in 6% of the patients enrolled in the Molteno studies; all cases were delayed and none were intraoperative. Significantly associated factors in a multiple logistic regression for SCH were the extent of intraocular pressure (IOP) drop after surgery, the post-operative IOP, a diagnosis of angleclosure glaucoma, and possibly the number of prior surgeries as well. Eyes with SCH did significantly less well in terms of visual acuity outcomes and were more likely to have inadequately controlled IOP. This study suggests that SCH occurs at the same frequency after Molteno implantation as after filtering surgery with antimetabolite use and that eyes with SCH do less well.

Thymoxamine test. Differentiating angle-closure glaucoma form open-angle glaucoma with narrow angles.

To help differentiate mild angle-closure glaucoma from open-angle glaucoma in patients with elevated intraocular pressure (IOP) and angles so narrow that the structures cannot be seen adequately, we used a thymoxamine hydrochloride eyedrop that induces miosis and tends to widen the angle. Thymoxamine does not contract the ciliary muscle and does not alter the IOP or facility of outflow in open-angle glaucoma, but it can relieve angle-closure glaucoma. A test with thymoxamine was performed in 26 patients because of this differential diagnostic dilemma. When gonioscopic, tonometric, and tonographic findings appeared to indicate a diagnosis of angle-closure glaucoma, a peripheral iridectomy was done. Subsequent (one to 27 months) observations have substantiated that testing with thymoxamine is a helpful aid in this differential diagnosis, and merits more widespread evaluation.

Mixed glaucoma.

Two hundred and sixty-seven eyes which underwent peripheral iridectomy for presumed angle-closure glaucoma were investigated. The diagnosis of angle-closure glaucoma was confirmed postoperatively in 258 eyes, in 201 of which the intraocular pressure became normal without further treatment and in 57 of which the postiridectomy IOP was elevated because of visible damage to the anterior chamber angle. Three eyes had open-angle glaucoma with a narrow angle. Six eyes had possible mixed (combined mechanism) glaucoma (2-2%). Mixed glaucoma is a rare, fortuitous combination of open-angle and angle-closure glaucoma rather than a distinct entity, and it might be advisable to avoid the term, which tends to be used for primary glaucomas of uncertain classification.