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 Table of Contents  
ORIGINAL ARTICLE
Year : 2018  |  Volume : 30  |  Issue : 3  |  Page : 187-192

Prospective study of hypermature cataract in Kanchipuram district: Causes of delayed presentation, risk of lens-induced glaucoma and visual prognosis


1 Department of Ophthalmology, Shri Sathya Sai Medical College and Research Institute, Chennai, Tamil Nadu, India
2 Department of Forensic Medicine, Shri Sathya Sai Medical College and Research Institute, Chennai, Tamil Nadu, India

Date of Web Publication17-Dec-2018

Correspondence Address:
Shruti Prabhat Hegde
Associate Professor, Department of Ophthalmology, SSSMCRI, Chennai, Tamil Nadu
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/kjo.kjo_50_18

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  Abstract 

Purpose: The aim of this study is to evaluate the reasons for delayed presentation, lens-induced glaucoma (LIG) incidence, intra- and post-operative course and visual outcome among patients with hypermature cataract in Kanchipuram district.
Materials and Methods: A prospective interview-based study was undertaken among 304 patients with hypermature over 3 years in the Ophthalmology department of a medical College located in Kanchipuram. Presence of LIG was noted. After small incision cataract surgery, intra- and post-operative complications, final best-corrected visual acuity (BCVA) at 6 weeks were noted and compared with delayed presentation using Chi-square test.
Results: Good visual acuity in the other eye was the reason for delayed presentation in 160 (52.6%) patients. Poor post-operative visual acuity was associated with delayed presentation (r = −0.203, n = 304 and P < 0.012). LIG was seen in 30 (10%) patients and 26 (8.5%) of these were pseudophakic in the fellow eye. 8 (2.6%) patients had zonular dehiscence. Difficulty in doing rhexis (156 patients), corneal edema (62 patients), and inferior subluxation of posterior chamber intraocular lens (12 patients) were the most common intraoperative, early and late postoperative complications. Final BCVA of 6/12 or better was seen in 282 patients.
Conclusion: Hypermature cataract and LIG are still seen in rural and suburban India and are more likely to develop in patients having good visual acuity in the fellow eye following previous cataract surgery. As delayed presentation is associated with poor postoperative outcome, it is important to educate the community about the need for early surgery.

Keywords: Delayed presentation, hypermature cataract, visual prognosis


How to cite this article:
Hegde SP, Sekharreddy MR, Kumar MR, Dayanidhi VK. Prospective study of hypermature cataract in Kanchipuram district: Causes of delayed presentation, risk of lens-induced glaucoma and visual prognosis. Kerala J Ophthalmol 2018;30:187-92

How to cite this URL:
Hegde SP, Sekharreddy MR, Kumar MR, Dayanidhi VK. Prospective study of hypermature cataract in Kanchipuram district: Causes of delayed presentation, risk of lens-induced glaucoma and visual prognosis. Kerala J Ophthalmol [serial online] 2018 [cited 2019 Mar 25];30:187-92. Available from: http://www.kjophthal.com/text.asp?2018/30/3/187/247587


  Introduction Top


Cataract is the most common cause of blindness in India.[1] The percentage of cases presenting with advanced cataract is high in rural and suburban India. Reasons for late presentation according to the previous studies are lack of caretakers, poverty, poor awareness, poor health education, acceptance of poor vision as a part of aging, unwillingness for surgery, and coexisting systemic diseases.[2],[3] Due to these factors hypermature cataract continues to form a significant percentage of overall cataract burden.

Hypermature cataract is defined as the stage of senile cataract in which the entire lens capsule is wrinkled and the contents have become solid and shrunken or soft and liquid. All the cataracts should be operated before they reach the stage of hypermaturity, as chances of intra- and post-operative complications are high in cases with hypermature cataracts.[4] Associated lens induced glaucoma (LIG), which is a potentially preventable condition, continues to be a cause of irreversible vision loss in India, especially among patients from rural areas. Intra-operative complications can arise due to various reasons like difficulty in doing continuous curvilinear capsulorrhexis (CCC), zonular dehiscence during nuclear emulsification or nucleus removal due to weak zonules. Both manual small incision cataract surgery (SICS) and phacoemulsification can be used for operating patients with hypermature cataract. Postoperative complications such as striate keratopathy, raised intraocular pressure, and prolonged inflammation are more commonly seen in individuals with hypermature cataract undergoing cataract surgery.[4] Patients with LIG might have poor visual recovery due to a preexisting optic atrophy.[5],[6]

We undertook this study as our center is located close to the suburbs of Chennai and a high volume of hypermature cataract patients regularly undergo cataract surgery in our institute.

The objective of the study was to evaluate the reasons for delayed presentation, the risk of LIG, intra- and post-operative course and visual outcome among patients with hypermature cataract admitted to our hospital.


  Materials and Methods Top


A hospital-based prospective study was undertaken over a period of 3 years from 2013 to 2016 in the ophthalmology department of a medical college hospital in south India. After obtaining an informed consent, all the patients with senile hypermature cataract who got admitted to the hospital and underwent cataract surgery were included in the study. The patients were interviewed one on one based on a face validated questionnaire designed for the history taking, physical examination and follow-up.

A total of 304 patients with hypermature cataract who had visual acuity of hand movements or perception of light were included in the study. A detailed history of the age, gender, address with regard to rural or urban area, duration of diminution of vision and the reasons for the late presentation was recorded. Patients who had already undergone cataract surgery in the fellow eye were interviewed to find if they were informed about the need to undergo cataract surgery in this eye during the previous surgery by the operating surgeon, nursing staff or ophthalmic assistant. Patients were also asked about being informed about the chances of developing a painful blind eye if the other eye was left unoperated.

Best-corrected visual acuity (BCVA) in both eyes pre- and post-operatively was recorded using Snellen's visual acuity chart. A detailed ophthalmic examination was done in both the eyes. The lens status of the other eye was noted. Intraocular pressure was measured using applanation tonometry in both the eyes. Patients with other comorbid conditions in the eye like preexisting glaucoma, complicated cataract, and pseudoexfoliation syndrome were excluded from the study.

Patients who presented with acute pain along with a history of prolonged diminution of vision were examined in detail to diagnose LIG. Those presenting with the deep anterior chamber, anterior chamber reaction, and a morgagnian cataract were classified as phacolytic glaucoma. Patients presenting with the shallow anterior chamber and intumescent cataract were classified as phacomorphic glaucoma., In addition, gonioscopy was performed in patients with clearer corneas. Patients with LIG were treated medically with anti-glaucoma medications before taking them up for surgery.

All the patients underwent SICS with posterior chamber intraocular lens (PCIOL) implantation. Superotemporal and temporal sclerocorneal tunnels of 6.5–7.5 mm were constructed. Trypan blue dye was introduced through side port entry for better visualization of the anterior capsule during capsulotomy in all the cases. CCC was attempted in all the cases. Can openers technique and envelope technique were utilized in those cases where rhexis could not be completed. PCIOL was not implanted in cases with insufficient zonular support or intraoperative zonular dehiscence. Trabeculectomy was performed in addition to SICS when indicated. All the surgeries were done by experienced surgeons. Intraoperative complications were recorded. Antibiotic steroid eye drops were given for all the postoperative patients along with anti-glaucoma and cycloplegic eye drops whenever required. Visual acuity and slit lamp examination were done on the 1st postoperative day and then at weekly intervals. Final BCVA was measured at 6 weeks after surgery. In cases with LIG, intraocular pressure was also monitored.

Statistical analysis

All the data collected was tabulated and analyzed using SPSS Statistics for Windows, Version 23.0 (IBM Corp., Armonk, NY, USA). The data are presented as rates, ratios and descriptive statistics. Correlation and association among various variables was calculated using Pearson's correlation coefficient and Chi-squared test and statistical significance was considered at P < 0.05.


  Results Top


Among 304, 146 (48%) were male patients and 158 (52%) were female patients. The age of the patients ranged between 40 and 70 years [Table 1]. About 70% (214) were hailing from rural area, whereas the remaining 30% (90) patients were from the urban area.
Table 1: Age distribution

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Duration of diminution of vision

Among 304 patients, 156 (51.3%) patients waited for >1year after the onset of diminution of vision before coming to the hospital for cataract surgery. 122 (40.1%) patients waited between 6 months and 1 year before coming to the hospital. Only 26 (8.5%) patients came to the hospital within 6 months of onset of diminution of vision. Correlation between duration of diminution of vision and final postoperative visual acuity is presented in [Table 2]. Pearson's correlation coefficient was computed to assess the relationship between duration of diminution of vision and postoperative visual acuity. There was a negative correlation found between the two variables (r = −0.203, n = 304, and P < 0.012). This shows that longer the duration of diminution of vision poorer the postoperative visual outcome. This finding is statistically significant at P = 0.012.
Table 2: Comparison of duration of diminution of vision and final postoperative visual acuity Chi square test (r =-0.203, n =304 and P < 0.012)

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Patients presenting with clinical features of lens-induced glaucoma

Lens-induced glaucoma was present in 10% of the patients. Most of these patients presented to our hospital with complaints of severe pain in the affected eye. Out of 30, 25 (84%) patients presented within a week of onset of symptoms and the remaining 5 patients presented more than a week after the onset of symptoms. Three of them had been treated by local practitioners. 26 (86.6%) patients had features suggestive of phacolytic glaucoma and only four patients had features of phacomorphic glaucoma. Intraocular pressure at presentation ranged from 30 to 56 mm of Hg. 26 (86.6%) of these patients had previously undergone cataract surgery in the other eye and had a visual acuity of 6/18 or better. The association between LIG and pseudophakia with a visual acuity of >6/18 was calculated using Chi-square test and there was a negative correlation found between the two variables (r = −0.181, n = 304 and P < 0.001) [Table 3]. This shows that patients having better vision in the other eye had higher risk of presenting with LIG.
Table 3: Association between lens induced glaucoma in one eye with pseudophakia and good visual acuity in the other eye- Chi-square test (r =-0.181, n =304 and P < 0.001)

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Visual acuity and lens status in the other eye

Visual acuity of the fellow eye was measured [Table 4] and the lens status was noted.
Table 4: Visual acuity in the other eye

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About 67% of the patients (204) in our study were pseudophakic who had already undergone cataract surgery in the other eye. Moreover, 176 of them had a fairly good visual acuity of >6/18. Eighty-six patients had immature cataract, and two patients had mature cataract in the other eye. There were 12 patients who presented with bilateral hypermature cataract.

More than 50% of the 204 patients with pseudophakia in this study had undergone surgery over a year back. Among these patients 166 (81.4%) approved of being informed about the other eye needing cataract surgery at a later date. However, only 50 (24.7%) patients had prior knowledge of developing painful blind eye if the surgery was delayed.

Reasons for delayed presentation

On being asked about delayed presentation to the hospital many patients had more than one reason. Details are mentioned in [Table 5].
Table 5: Number of patients with different reasons for delayed presentation to the hospital

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Surgical management and outcome

All the patients underwent SICS and PCIOL was implanted in 296 patients. Five patients needed additional trabeculectomy. CCC was done in 199 patients and other methods were used in remaining 105 cases. Zonular dehiscence was seen in a total of 8 cases (three with preexisting zonular dehiscence and five with intra-operative zonular dehiscence). Anterior chamber intraocular lens (ACIOL) was implanted in two patients and remaining six were left aphakic and planned for a secondary IOL implantation. Postoperatively, corneal edema (62 patients), anterior chamber inflammation (45 patients) and raised intraocular pressure (34 patients) were the common complications. 12 patients had inferior subluxation of PCIOL on final follow-up. Final postoperative visual acuity of 6/12 or better was seen in 282 patients.


  Discussion Top


With increase in ageing population, cataract blindness continues to be a challenge in India in spite of increase in number of cataract surgeries.[7] Hypermature cataract still constitutes a significant percentage of total cataract cases, especially among the rural population.

Various studies done in the past have reported its incidence as 11.5%, 7.1%, and 1.4%.[8],[9],[10] However, all these studies are population-based studies done to study the incidence of cataract in general. There are very few studies done exclusively on hypermature cataracts.

Increasing age, female sex and illiteracy are shown to be associated with cataract blindness, as previously proven by a large-scale survey done in south India.[11] Another recent study also shows female gender, socioeconomic status, literacy status, and urban-rural difference to be major determinants of cataract surgical coverage.[12] Our study did not show a significant relation between age and female gender with incidence of cataract. This is in contrast to the previous studies on incidence of cataract and LIG which showed increased incidence in female patients.[11],[12],[13] It could be because ours was a hospital based study. The mean age of presentation was 58 years. Only 10% of the patients were >70years of age. More than one-fourth of the patients (86) with hypermature cataract were <50 years of age. This is an interesting finding and warrants an independent study to evaluate high incidence of hypermature cataract in lower age groups.

The correlation between longer duration of diminution of vision and poor postoperative visual acuity could be due to increasing degenerative changes in the lens and zonules with longer duration of cataract.

Not many previous studies have looked into good visual acuity in the previously operated eye as a risk factor for developing LIG in the affected eye. We found a statistically significant correlation between the two. Phacolytic glaucoma was seen more commonly than phacomorphic glaucoma. A study done in Nepal reported the incidence of phacomorphic glaucoma to be much higher than phacolytic glaucoma.[14] Another study from India reported an equal incidence of both.[15] Our study included only patients with hypermature cataract and majority of the patients had a morgagnian cataract. This could explain a high number of phacolytic glaucoma cases in our study.

The most common lens status in the other eye was pseudophakia (204 patients) and the most common cause stated for the delayed presentation was being able to manage with good vision in one eye. This has not been discussed in many studies done in the past. A study done in the Konkan area of India sites inability to afford as the main cause for delaying surgery.[16] The study also mentions poor postoperative vision as one of the causes in discouraging the patients from getting operated. This was not true in our study where most of the patients who were operated earlier had a good postoperative visual acuity. Another study from south India has shown fear of surgery as the main cause preventing cataract patients from attending the free eye camps.[17] The study also made an important observation that the majority of the patients who would have otherwise benefitted from eye treatment were not utilizing the available resources. We agree with this as large number of patients were aware of their eye condition needing surgical treatment but did not come to the hospital for surgery. With this observation we can infer that widespread coverage alone will not solve the problem. Probably, a more holistic approach is required which should aim at bringing a change in the attitude of the patients especially those hailing from rural areas and low socioeconomic classes toward cataract surgery. This might be achieved by educating patients and the community about benefits of early surgery, creating awareness about safety of cataract surgery, stressing on the point that it is done under local anesthesia and thus there is hardly any systemic risk involved. Patients also need to be told that they do not need any helpers and can carry on with their daily routine soon after the surgery. Reinforcing the trust of patients is also very important. Poor postoperative outcome in the community has been sighted as an important reason for patients not coming forward for surgery in few of the earlier studies.[16],[17],[18] However in our study, among 204 patients who were pseudophakic in one eye, 176 patients had a visual acuity >6/18. This meets the WHO target of >80% having good vision with available correction. In spite of this patients delayed getting operated in the other eye. Thus increasing the awareness comes as the top priority to reduce the number of hypermature cataracts. Fear of surgery was the chief reason for delayed presentation among patients with bilateral hypermature/mature cataract. It is very unfortunate that in spite of rigorous coverage of rural and suburban areas under District blindness control society scheme bilateral hypermature cataracts are seen even now.

An important inference drawn from our study is that advising the patients about second eye cataract surgery alone may not be sufficient in bringing down the incidence of hypermature cataract. Patients especially those from rural areas may manage with good vision in one eye ignoring the other eye completely. It is important on the part of health care professionals to stress the fact that when a cataract is left unoperated, it could complicate into a LIG thereby making a painless blind eye to painful blind eye. When this is carried out routinely, the number of patients opting for early second surgery may gradually increase.

We agree with Yorston that SICS can be a good alternative to Phacoemulsification while doing high volume cataract surgeries in developing countries.[19] It was found that for advanced cataracts in developing countries manual SICS could be a better procedure.[20] Although postoperative astigmatism is said to be more in SICS when compared to phacoemulsification, a previous study found the difference to be small.[21] The study did not find any difference between SICS and phacoemulsification as far as the endothelial loss was considered. The relative risk of nucleus drop is said to be slightly more in phacoemulsification as compared to SICS and this risk could be potentially higher in cases of hypermature cataracts.[22] The commonest intraoperative complication in our study was difficulty in doing CCC (34.5% patients) which was due to overrunning of the rhexis flap and Can openers and envelop techniques were used to complete the capsulotomy. The incidence is comparable to that in a previous study, wherein capsulorrhexis was incomplete in 28.3% of all white cataracts operated.[23] Zonular dehiscence and posterior capsule rupture with or without vitreous loss were seen in 5 (1.67%) cases. The incidence of posterior capsule rupture in white cataracts reported by Chakrabarti et al. was 1.9% whereas study done on hypermature cataracts by Shahid et al. in Pakistan found this to be 12%. Use of preoperative NSAID eye drops to maintain intraoperative pupillary dilatation, liberal use of viscoelastic substances, use of trypan blue dye to stain the anterior capsule before capsulotomy and surgeries being done by experienced surgeons could be the factors responsible for low percentage of posterior capsule ruptures seen in our study.

A total of 5 patients, all with LIG, needed additional trabeculectomy. Delayed presentation (>1-week duration) and insufficient response to medical management of intraocular pressure were taken as indications for trabeculectomy.

The most common immediate postoperative complication found was corneal edema a finding similar to that in two previous studies.[4],[23] At 6 weeks, the most common complication was inferior subluxation of PCIOL. Within this limited follow-up period, no cases of posterior capsular opacification or bullous keratopathy were reported.

As this study was done in a hospital, the results may not be entirely reflecting the situation in the general population. Further, as some responses regarding the duration of diminution of vision and advice given during the previous surgery depend on patient's memory, there is an element of recall bias inherent in the study design. Hence the results of this study have to be applied keeping in mind these limitations. Furthermore, a long-term follow-up could not be done as most of the patients did not turn up after the final follow-up at 6 weeks.


  Conclusion Top


In spite of wide coverage under national program hypermature cataracts are commonly found in the rural and suburban population of India. Educating the community as a whole about the effectiveness and minimal risk of modern cataract surgery is important to bring down the incidence of hypermature cataracts. Patients undergoing cataract surgery and getting good postoperative visual acuity in one eye are most likely to ignore and develop hypermature cataract in the other eye. These patients should be made aware of chances of developing painful loss of vision in the other eye if left unoperated. SICS is a very good choice in these patients and postoperative results are comparable to that of phacoemulsification.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 
  References Top

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Thulasiraj RD, Nirmalan PK, Ramakrishnan R, Krishnadas R, Manimekalai TK, Baburajan NP, et al. Blindness and vision impairment in a rural South Indian population: The Aravind Comprehensive Eye Survey. Ophthalmology 2003;110:1491-8.  Back to cited text no. 1
    
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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. 2
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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. 3
    
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Shahid E, Sheikh A, Fasih U. Complications of hypermature cataract and its visual outcome. Pak J Ophthalmol 2011;27:258-62.  Back to cited text no. 4
    
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Patra R, Mallireddy S. A clinical study on lens induced glaucoma and its visual outcome in patients visiting rims, Srikakulam. J Evol Med Dent Sci 2015;4:10294-300.  Back to cited text no. 5
    
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George R, Rupauliha P, Sripriya AV, Rajesh PS, Vahan PV, Praveen S, et al. Comparison of endothelial cell loss and surgically induced astigmatism following conventional extracapsular cataract surgery, manual small-incision surgery and phacoemulsification. Ophthalmic Epidemiol 2005;12:293-7.  Back to cited text no. 21
    
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    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5]



 

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