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ORIGINAL ARTICLE
Year : 2015  |  Volume : 3  |  Issue : 2  |  Page : 56-62

Study of the incidence, mechanism, various modes of presentation and factors responsible for the development of lens-induced glaucomas


Department of Ophthalmology, Advanced Research Center, Narayana Medical College and Hospitals, Nellore, Andhra Pradesh, India

Date of Web Publication17-Dec-2015

Correspondence Address:
Chandrasekhar Gujjula
Department of Ophthalmology, Narayana Medical College and Hospitals, Nellore, Andhra Pradesh
India
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DOI: 10.4103/1858-6538.172097

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  Abstract 

Objectives: The present study undertaken to study the factors responsible for the development of lens-induced glaucomas (LIGs), factors, and various modes of presentation in LIGs.
Methodology: A minimum of 50 cases of LIG were selected based on simple random sampling, who attended the Department of Narayana Medical College Hospital and were diagnosed with LIG. Based on the clinical findings, etiological diagnosis of LIG was made.
Results: Out of the 50 cases, 34 cases (68%) were diagnosed as phacomorphic glaucoma, 12 cases (24%) were of phacolytic glaucoma, two each (4%) were lens-particle glaucoma and glaucoma secondary to subluxation/dislocation of lens.
Conclusion: There was no influence of sex, religion, or occupation on the incidence or occurrence of LIGs. Majority of the patients had good vision in the other eye as a result of which they neglected the affected eye till they developed LIG leading to pain during the time of presentation. Hence, it is important to advice the patients regarding the early surgical treatment of cataract before they develop complications.

Keywords: Intra-ocular pressure, lens-induced glaucoma, lens-particle glaucoma, phacolytic, phacomorphic


How to cite this article:
Gujjula C, Kumar S, Varalakshmi U, Shaik MV. Study of the incidence, mechanism, various modes of presentation and factors responsible for the development of lens-induced glaucomas. Albasar Int J Ophthalmol 2015;3:56-62

How to cite this URL:
Gujjula C, Kumar S, Varalakshmi U, Shaik MV. Study of the incidence, mechanism, various modes of presentation and factors responsible for the development of lens-induced glaucomas. Albasar Int J Ophthalmol [serial online] 2015 [cited 2017 Nov 19];3:56-62. Available from: http://www.bijojournal.org/text.asp?2015/3/2/56/172097


  Introduction Top


The human crystalline lens is a unique transparent, biconvex intraocular structure, which lies in the anterior segment of the eye between the iris and vitreous body are suspended radially at its equator by zonular fibers to the ciliary body, it lies in the patellar fossa and enclosed in capsular bag. With a cataract backlog of around 12 million [1] and annually increasing at an estimated rate of 3.8 million,[1],[2] it is not surprising that the occurrence of lens-induced glaucoma (LIG) is frequent event in India.[3],[4] LIG due to hypermature cataracts is an important cause of secondary glaucoma in the developing world. There is an ever-increasing backlog of cataract due to the population explosion, increased life expectancy, and low productivity in terms of utilization of the available surgical services. The uptake of eye care services by the rural community has also been suboptimal in countries like India where LIG is not an uncommon cause of ocular morbidity.

The term “phacolytic" should be reserved for the sudden onset of open-angle glaucoma caused by leaking through a relatively intact capsule in mature or hypermature cataract. Intraocular pressure (IOP) elevation with uveitis may occur subsequent to release of lens material into the anterior chamber through a surgically or traumatically created opening in the lens capsule. Unlike phacolytic glaucoma (PL), in which IOP elevation is detected at the onset of symptoms, phacoanaphylactic uveitis is rarely associated with glaucoma except possibly in advanced stages of severe inflammation.

The classic clinical description of anaphylaxis is chronic uveitis with onset 1–14 days after extracapsular cataract extraction or trauma to the lens. Increasing lens thickness due to growth of the lens cortex is a well-recognized factor in the development of primary angle closure glaucoma. Other factors such as short axial length of the globe, preexisting individual differences in anatomy of the anterior chamber angle, and zonular relaxation may also contribute to variable extents. When angle-closure glaucoma develops due to an intumescence of the lens that can be distinguished from normal lens growth, the term “phacomorphic glaucoma (PM)" is applied. It has long been recognized clinically that several forms of glaucoma may occur in association with the formation of cataracts. Flocks et al.[5] reported histological findings suggesting that the glaucoma-inducing mechanism was a macrophagic response to lens material and hence called it PL. Epstein et al.[6] showed evidence of high molecular weight proteins responsible for the obstruction of aqueous outflow and termed it lens-particle glaucoma. Tomey and al-Rajhi [7] in a short study of patients with PM, the attack was relieved in all cases by laser iridectomy, which may be helpful to bring the pressure under control before proceeding with cataract surgery.

Dislocation of the lens may occur without associated ocular or systemic abnormalities as a congenital anomaly or as a spontaneous disorder later in life. Several studies [8],[9],[10],[11] showed ectopic lentis et pupillae is a condition with a slit-shaped pupil with subluxation in the opposite direction. This study emphasizes the importance of early diagnosis, patient education, frequent and regular surveillance of all cases of cataract which go for hypermaturity, before a cataract becomes hypermature cases should be operated.

Hence the present study was undertaken and aimed at a clinical study of various LIGs, their management as practiced in the Department of Ophthalmology, Narayana Medical College and Hospital, Nellore, Andhra Pradesh, India.


  Methodology Top


Source of data

All the 50 patients were those who attended the Inpatient Department of Narayana Medical College Hospital and were diagnosed with LIG.

Inclusion criteria

The following criteria were applied to clinically diagnose the various types of LIGs:

Phacomorphic glaucoma

  • Shallow anterior chamber
  • Intumuscence of mature cataract
  • Raised IOP.


Phacolytic glaucoma

  • Deep anterior chamber
  • Hypermature cataract
  • Raised IOP
  • Varying degree of aqueous flare and cells and no K. P's.


Phacotoxic uveitis/lens particle glaucoma

  • Hypermature cataract
  • Traumatic rupture of lens capsule or postoperative retained lens matter
  • Mild to moderate signs of iridocyclitis, deep anterior chamber
  • Very few or no K. P's.


Phacoanaphylactic uveitis with secondary glaucoma

  • History of cataract surgery or injury to lens
  • Very severe clinical picture of iridocyclitis
  • Large number of mutton fat like K. P's.


Glaucoma secondary to ectopia lentis

  • Anterior or posterior dislocation
  • Lens across pupillary plane
  • Raised IOP.


Exclusion criteria

  • Cases of primary glaucoma associated with cataract
  • Cases of LIGs with significant anterior and posterior segment pathology
  • Aphakic or pseudophakic glaucoma
  • Other associated glaucoma's with cataract such as pseudoexfoliation, glaucoma, etc.


Sampling size and methods

A minimum of 50 cases of LIG were selected based on simple random sampling. Age and sex were not criteria in selecting cases. The study was made on patients diagnosed with LIG and admitted to the ophthalmic ward.

Patient evaluation

All the 50 patients after clinical diagnosis were admitted and a detailed history and examination were done. Detailed history pertaining to the causation of glaucoma in the affected eye was ascertained. The details of history included the duration and progress of diminution of vision, onset of pain, redness, watering, and photophobia in the affected eye and associated symptoms such as headache, nausea, and vomiting were taken. Any history of ocular trauma of previous surgery in the eye was enquired. In the affected eye, vision was recorded and retinal function test was done. The IOP was measured using applanation tonometer, two readings were taken to establish the final IOP. B-scan was done in the affected eye as the fundus was not visible to rule out posterior segment pathology. A detailed examination of the other eye was done.

The above data were compiled using a standardized proforma and at the end of the study the data was analyzed statistically using the Chi-square method and the probability value. The statistical analysis was done using the SPSS version 16.0 (SPSS Inc. Chicago, US). Statistically Chi-square test (χ2) and probability values (P) were used and P < 0.05 was considered statistically significant.


  Results Top


Among the 50 cases that were included in the study, majority of the cases were in the age group of 66–75 years (40%). The youngest case in the study group was 52 years old whereas the oldest was 81 years old. The incidence of LIG was slightly higher in females (58%) than in males (42%) [Table 1].
Table 1: Age distribution

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Eye affected

In 19 cases (38%), right eye was affected whereas in 31 cases (62%) left eye was affected.

Duration of symptoms

Out of the 50 cases, 29 cases (58%) presented within the 1st week and 11 cases (22%) within 2nd week and the rest presented within 3 weeks after the development of symptoms.

Etiological diagnosis

Out of the 50 cases, 34 cases (68%) were diagnosed as PM, 12 cases (24%) were of PL, two each (4%) were lens-particle glaucoma and glaucoma secondary to subluxation/dislocation (S/D) of lens [Table 2] and [Figure 1].
Table 2: Etiological diagnosis

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Figure 1: (a) Traumatic anterior dislocation of lens with pupillary block glaucoma; (b) lens particle glaucoma; (c) phacomorphic glaucoma; (d) phacolytic glaucoma

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Condition of other eye

Out of the 50 cases, 22 cases (44%) presented with pseudophakia, 21 cases (42%) presented with combined immature and mature cataract, six cases (12%) were aphakic, and normal crystalline lens was found in one case (2%).

Vision in other eye

Overall, 30 cases (60%) had fairly good vision in the other eye whereas the remaining 20 cases (40%) had poor vision in the other eye.

Preoperative intraocular pressure

A total of three cases (06%) presented with IOP <30 mmHg, 20 cases (40%) with IOP between 30 and 40 mmHg. Rest of the cases presented with IOP more than 40 mmHg (54%). The highest pressure recorded during the study was 78.00 mmHg [Table 3].
Table 3: Preoperative intraocular pressure

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  Discussion Top


This study included 50 patients with different LIGs. The patients were followed up from the time of admission and surgery till 6 weeks postoperatively and the factors influencing the final visual outcome were analyzed.

In this study majority of patients were also found between 66 and 75 years. But in the study by Dr. Ajab revealed majority of patients between 50 and 70 years. So.majority of patients of LIG are between 50 and 70 years. In this study, females seemed to have an increased risk of having LIG compared to males with ratio of 1.7:1. It is also found that the majority (77.78%) of cases occurred among lower socioeconomic strata in the society. In a study by Dhar et al.[12] showed that 56% of females were in preponderance were in preponderance compared to males 43.54% and in a ratio roughly 4:3. In this study and including all above studies, females seemed to have significant increased risk of having this glaucomas. Though it is possible that these entities are more common in females because of socioeconomic constraints, we also have to consider the fact that the prevalence of cataract itself is more common in females than males. All the patients who presented with LIG were from rural areas and of poor socioeconomic background. Socioeconomic factors like most of the patients were daily wage workers, lack of literacy, depends on other family members of family. This might be one of the causes for late presentation with complications of cataract.[11] Lens incuces glaucoma-a clinical study. As per socioeconomic status scale, there was no patient from upper and upper middle class. Only 19.15% cases were from lower middle class, while 55.60% cases were from upper-lower class, and 25.23% cases were from lower class.[11]

In Kothari et al.[13] study, the reason for delayed reporting for treatment leads to serious complications like LIG. In spite of services for cataract surgery available so easily reasons such as poor health education, acceptance of poor vision as part of aging, fear of operation, lesser expectations and socioeconomic constraints appear to leading causes.

In their study, Rijal and Karki [14] also found that after taking history of all patient of LIG, all cases are having poor socioeconomic condition due to which negligence towards symptoms and disease cases came after longer duration of symptoms.

Including this study and all the above other studies, it is found that all cases having poor socioeconomic condition, illiteracy, dependency on other family member have high prevalence of LIG.

In this study, left eye affected by 52.5% and right affected by 47.5%. Primary open angle glaucoma is usually bilateral condition although the changes may be asymmetrical. Primary angle closure patients usually have similar narrow angle in both eyes. In case of unilateral glaucoma are may underlying secondary glaucoma causes. In Chan et al.,[15] Singapore Malay Eye Study, visual functioning was significantly poorer only for individuals with unilateral but not bilateral glaucoma, compared to controls. In this study, they found all cases of unilateral glaucoma had poor visual functioning compared to bilateral glaucoma cases.

Rijal and Karki [14] found left eye is more affected compare to the right eye in LIG cases.

All cases of LIGs studied were unilateral. In 31 cases (62%), left eye was affected while in 19 cases (38%) right eye was affected. Statistically χ2 = 19.321 and P = 0.9, suggesting that there was no preponderance for the right or left eye.

Good visual acuity was achieved, in cases presented within 1 week (62.06%) was more than the cases presented beyond 2 weeks (12.5%), whereas poor visual acuity of <6/60 was more in cases presented beyond 2 weeks (50%). In this study, duration of symptoms had a linear relation with best-corrected visual acuity at the final follow-up. More the delay in presentation, poorer was the visual outcome, which was both clinically and statistically significant (P = 0.001).

Among the 50 cases, majority of the cases (58%) presented with pain and redness within the first week after developing the symptoms. The rest of 21 cases (42%) presented after 1 week. The above data shows that most patients who neglected the loss of vision presented within a week of developing pain and redness.

The Lahan study of 1998 found that duration of pain and high level of IOP at presentation in phacomorphic group was associated with poor visual outcome at discharge, while in phacolytic group no such association was made out.[15] According to Prajna et al.'s study,[16] there is significant risk of obtaining poor visual acuity with duration between onset of pain and surgery exceeded more than 5 days. In this study, age and duration of symptoms shows higher significant association with the higher risk of poor visual outcome postoperatively.

Dimitris [17] study shows higher association with longer duration of pain and increase IOP, In this series final visual outcome is worse than in other studies, probably because the majority of the patients reported later than 10 days after the onset of pain.

In Kothari et al.'s [13] study, patients got no visual improvement or only marginal improvement in vision after the operation. This was the group where time lag between the development of symptoms of pain/redness and reporting for treatment was the longest. They found that longer the duration of symptoms and greater the time to start the treatment for LIG. Also many people especially in rural areas take treatment for redness and pain in eyes from some local practitioners who miss the diagnosis initially. It was only when the symptoms became worse, they reported to the hospital. Another factor about late reporting found was that the very elderly visually handicapped persons were left to their own fate as no one bothered to bring them to the hospital.

All of the above studies shows that longer the duration of symptoms can leads to worse in visual outcome post operatively. This is due to probably due to the susceptibility of the optic nerve to damage. In the 50 cases, 22 cases (44%) presented with pseudophakia, 21 cases (42%) presented with either immature or mature cataract, 1 case (2%) had a normal crystalline lens in the other eye while a further 6 cases (12%) were aphakic.

Though clinically significant but not statistically, χ2 = 39.566 and P = 0.1 indicating that the patients having pseudophakia or normal crystalline lens or aphakic in the other eye formed a major bulk of this study.

Overall, 30 cases (60%) had fairly good vision in the other eye whereas the remaining 20 cases (40%) had poor vision in the other eye.

Also χ2 = 14.980, P = 0.002 for patients having good vision in other eye indicating the significant association between good vision in other eye developing LIG. The other eye in a study by Dhar [12] invariably quiet with other study.

As a result of having fairly useful vision in the other eye, most of these patients neglected the other eye till they developed complication in the affected eye.

This emphasizes the importance of early treatment of other eye in patients with bilateral cataract.

In this study, 68% PMG and 24% IPLG was observed.

In this study, none of the PMG occured below the age of 50 years.

No cases of phacoanaphylactic glaucoma were reported indicating the refinement of cataract surgery. Phacomorphic and PL which are seen following neglecting the cataract till it attains hypermaturity and leads to glaucoma formed the main bulk of cases constituting 92% of cases. This emphasizes the importance of early detection and treatment of cataract.

The Prajan et al. study 10 deals with the clinical modes of presentation, the postoperative visual results, and the risk factors that relate to the visual outcome of such cases. The percentage of PMs (52.7%) is slightly higher than phacolytic (47.3%) and the latter is more common with increasing age probably due to aggregation of high molecular weight proteins in the crystalline lens over time.

Rijal and Karki,[14] Visual outcome and IOP control after cataract surgery in LIGs PM was seen more (65%) than PL (35%) in our study. This is more or less similar to earlier studies done in the country at Lahan by Dr. Pradhan et al.[18]

In this study, phagocytic LIG observed more than phacomorphic LIG.

The present study demonstrates that PM is more common than PL. Rijal and Karki,[14] Sharma et al.[3] too have documented PM to be common than other forms of LIG.

In the 50 cases under study, 94% cases presented with only reception of light, 4% with hand movements only and 2% with counting fingers close to face. Best corrected visual acuity (BCVA) of 6/12 or better was taken as good visual acuity, and <6/60 as poor visual outcome.

In this study, BCVA of 6/12 or better is slightly higher (44%) than Lahan study series (31.40%). There was a significant proportion of cases that had poor vision, with visual acuity <6/60 (22%) similar to Lahan study (21.0%). Thus, in this study higher percentage of cases has achieved good visual recovery and almost equal percentage of cases have poor visual outcome when compared to Lahan study series. BCVA in this study of 6/12 or better was low (44%) and poor vision of <6/60 was higher (22%) compared to Madurai study, with 59.13% and 11.82%, respectively.

In this study, good visual acuity achieved by cases with PL (53.33%) was more than PM (37.04%), and this difference was clinically significant but statistically not significant (P > 0.05). Poor outcome of <6/60 showed no significant difference between PLG (26.67%) and PMG (29.63%).

In an effort to study the relation of secondary glaucoma with rise of IOP and visual acuity, the following observations were made.

Clinically, significant proportion of cases with IOP at presentation <30 mmHg (67%) achieved good visual acuity, than cases with IOP more than 40 mmHg (20%), whereas no significant difference was found for poor outcome. The correlation between height of IOP and visual outcome was clinically significant but statistically insignificant (P > 0.05). Madurai study also had found no statistically significant association between the level of preoperative IOP and final visual acuity.[5]

The IOP at the last follow-up was reduced to normal limits (16.44 ± 6.54 mmHg). This indicates that, in LIGs IOP should be reduced by medical line of treatment preoperatively to as normal as possible, so as to achieve stable IOP postoperatively with no further anti-glaucoma medications.

It is found that the IOP tends to be higher with the delay in presentation beyond 2 weeks than the duration of presentation of <2 weeks. Though mean IOP at last follow-up was normal (16.44 ± 6.54 mmHg), cases with delay in presentation between 2 and 4 weeks and more than 30 days tend to be on higher end of normal (18.44 ± 6.98 mmHg and 18.67 ± 12.48 mmHg).

Thus, delay of more than 2 weeks in presentation would result in higher IOP, especially if the delay is beyond 30 days, which is clinically significant.

There was no significant difference in IOP among LIG sub groups both clinically and statistically. The highest pressure recorded was 78.00 mmHg with applanation tonometer in the case with phacomorphic glaucoma.

In a study done by Rijal and Karki.,[14] preoperative IOP (Applanation) ranged from 24.0 to 59.0. Twenty cases (50%) >43 mmHg. Ten (25%) cases >30 mmHg and 10 (25%) cases 24–30 mmHg. i.e., 51.7% out of 60 cases study found that number of cases between preoperative IOP between 21 and 30 mm of Hg is 7 (11.6%), between 31 and 40 mm of Hg is 10 cases (16.7%), between 41 and 50 mm of Hg is 31 cases (52.7%), more than 50 mm of Hg is 12 cases 72 (20%) so cases having preoperatively IOP more than 40 mm of Hg is 43 cases (71.7%), which is quite similar to result in this study. Including all above studies it found that many cases of LIG is more in number above IOP of 40 mm of Hg and less number of cases of LIG between 22 and 30 mm of Hg.

In the present study, clinically significant proportion of cases with IOP at presentation <30 mmHg (67%) achieved good visual acuity, than in cases with IOP more than 40 mmHg (20%), whereas no significant difference was found for poor outcome. The correlation between height of IOP and visual outcome was clinically significant but statistically not significant (P > 0.05), so the present study is not correlated with the above studies.


  Conclusion Top


There was no influence of sex, religion, or occupation on the incidence or occurrence of LIGs. PM is the most common type of LIG accounting for 68% of the cases followed by PL with 24% of cases. Majority of the patients had good vision in the other eye as a result of which they neglected the affected eye till they developed LIG leading to pain during the time of presentation. Hence, it is important to advice the patients regarding the early surgical treatment of cataract before they develop complications.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 
  References Top

1.
Ministry of Health and Family Welfare: Problem of Blindness in India. In: Status of National Program for Control of Blindness (NPCB). New Delhi: Government of India; 1993. p. 2.  Back to cited text no. 1
    
2.
Minassian DC, Mehra V. 3.8 million blinded by cataract each year: Projections from the first epidemiological study of incidence of cataract blindness in India. Br J Ophthalmol 1990;74:341-3.  Back to cited text no. 2
    
3.
Sharma RG, Verma GL, Singhal B. A clinical evaluation of Scheie's operation with sclerectomy along with lens extraction in lens induced glaucoma. Indian J Ophthalmol 1983;31:639-41.  Back to cited text no. 3
[PUBMED]  Medknow Journal  
4.
Jain IS, Gupta A, Dogra MR, Gangwar DN, Dhir SP. Phacomorphic glaucoma – Management and visual prognosis. Indian J Ophthalmol 1983;31:648-53.  Back to cited text no. 4
[PUBMED]  Medknow Journal  
5.
Flocks M, Littwin CS, Zimmerman LE. Phacolytic glaucoma; a clinicopathologic study of one hundred thirty-eight cases of glaucoma associated with hypermature cataract. AMA Arch Ophthalmol 1955;54:37-45.  Back to cited text no. 5
[PUBMED]    
6.
Epstein DL, Jedziniak JA, Grant WM. Obstruction of aqueous outflow by lens particles and by heavy-molecular-weight soluble lens proteins. Invest Ophthalmol Vis Sci 1978;17:272-7.  Back to cited text no. 6
[PUBMED]    
7.
Tomey KF, al-Rajhi AA. Neodymium: YAG laser iridotomy in the initial management of phacomorphic glaucoma. Ophthalmology 1992;99:660-5.  Back to cited text no. 7
    
8.
Luebbers JA, Goldberg MF, Herbst R, Hattenhauer J, Maumenee AE. Iris transillumination and variable expression in ectopia lentis et pupillae. Am J Ophthalmol 1977;83:647-56.  Back to cited text no. 8
[PUBMED]    
9.
Nelson LB, Maumenee IH. Ectopia lentis. Surv Ophthalmol 1982;27:143-60.  Back to cited text no. 9
[PUBMED]    
10.
Townes PL. Ectopia lentis et pupillae. Arch Ophthalmol 1976;94:1126-8.  Back to cited text no. 10
[PUBMED]    
11.
Goldberg MF. Clinical manifestations of ectopia lentis et pupillae in 16 patients. Ophthalmology 1988;95:1080-7.  Back to cited text no. 11
    
12.
Dhar GL, Bagotra S, Bhalla A. Lens induces glaucoma – A clinical study. Indian J Ophthalmol 1984;32:456-9.  Back to cited text no. 12
[PUBMED]  Medknow Journal  
13.
Kothari R, Tathe S, Gogri P, Bhandari A. Lens-induced glaucoma: The need to spread awareness about early management of cataract among rural population. ISRN Ophthalmol 2013;2013:581727.  Back to cited text no. 13
    
14.
Rijal AP, Karki DB. Visual outcome and IOP control after cataract surgery in lens induced glaucomas. Kathmandu Univ Med J (KUMJ) 2006;4:30-3.  Back to cited text no. 14
    
15.
Chan EW, Chiang PP, Wong TY, Saw SM, Loon SC, Aung T, et al. Impact of glaucoma severity and laterality on vision-specific functioning: The Singapore Malay eye study. Invest Ophthalmol Vis Sci 2013;54:1169-75.  Back to cited text no. 15
    
16.
Prajna NV, Ramakrishnan R, Krishnadas R, Manoharan N. Lens induced glaucomas – Visual results and risk factors for final visual acuity. Indian J Ophthalmol 1996;44:149-55.  Back to cited text no. 16
[PUBMED]  Medknow Journal  
17.
Papaconstantinou D, Georgalas I, Kourtis N, Krassas A, Diagourtas A, Koutsandrea C, et al. Lens-induced glaucoma in the elderly. Clin Interv Aging 2009;4:331-6.  Back to cited text no. 17
    
18.
Pradhan D, Hennig A, Kumar J, Foster A. A prospective study of 413 cases of lens-induced glaucoma in Nepal. Indian J Ophthalmol 2001;49:103-7.  Back to cited text no. 18
[PUBMED]  Medknow Journal  


    Figures

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    Tables

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