ORIGINAL ARTICLE  
Practice Patterns in the Management of  
Strabismus in Pakistan  
Nasir Ahmed1, Muhammad Shaheer2, Sarmad Zahoor3, Salman Hamza4, Samran Asim5  
1’3’4’5King Edward Medical University, 2Lahore General Hospital, Lahore  
ABSTRACT  
Purpose: To study the current practice patterns of pediatric ophthalmologists in the management of strabismus  
in Punjab.  
Study Design: Questionnaire based Practice pattern survey.  
Place and Duration of Study: Teaching hospitals of Punjab from July 2018 to July 2019.  
Material and Methods: This study was conducted at ophthalmology departments of various teaching hospitals of  
Punjab. A questionnaire was designed to find out the current practice pattern for management of strabismus.  
Ophthalmologists who were members of Ophthalmological Society of Pakistan (OSP), having their expertise in  
strabismus surgery for more than 5years and practicing pediatric ophthalmology were selected. Discussion was  
also held regarding questionnaire and practices being performed after filling the proforma. This data was  
compiled, analyzed and was converted to a summary in points.  
Results: We contacted 90 ophthalmologists out of whom 76 responded to our Questionnaire. Complete  
Orthoptic Assessment was performed by only 46% (35) of the ophthalmologists. Prism cover test was used as a  
diagnostic tool by 70 (92%) ophthalmologists. Rest of the ophthalmologists used Synoptophore with it.  
Percentage of ophthalmologists performing cycloplegic refraction was very low. Only 5 (6.57%) surgeons used  
adjustable sutures. Only 46% of surgeons used to explain the complications of Anesthesia. More than 90% of  
surgeons explained the surgical procedures being done, its complications, post-operative care and need to use  
glasses or need for orthoptic exercises. All the surgeons kept follow up of the patients on 1st post-operative day.  
Conclusion: The current practices in strabismus need to be standardized and a consensus should be developed  
at a national level.  
Key Words: Strabismus, Prisms, Refraction, Orthoptic assessment.  
How to Cite this Article: Ahmed N, Shaheer M, Zahoor S, Hamza S, Asim S. Survey of Practice Patterns in the  
Management of Strabismus in Pakistan. Pak J Ophthalmol. 2020, 36 (2): 115-119.  
Doi: 10.36351/pjo.v36i2.889  
INTRODUCTION  
myths often considering a strabismic person to be of  
low Intelligent Quotient and sign of bad destiny has  
also contributed in affecting the life of these patients6.  
Symptoms include disturbed vision, double vision,  
headache, eye strain, abnormal posturing of head and  
easy fatigability after reading7. Newborns often have  
misalignment that resolves spontaneously. However  
most of the time it remains even in the adult life8. The  
main purpose of treatment is restoration of binocular  
vision, normal alignment of eyes, stereoacuity and  
correction of abnormal head posture9. Treatment  
modalities to achieve the targets are; use of patches,  
Strabismus is a fairly common problem having multi  
directional impacts affecting different populations with  
a prevalence varying from 0.5 to 5 %1,2,3,4. Strabismus  
is associated with amblyopia, strange cosmetic look,  
decreased social esteem and emotional discouragement  
disturbing quality of life of the patient5. Stereotypical  
Correspondence to: Nasir Ahmed Chaudhary  
Institute of Ophthalmology, Mayo Hospital, Lahore  
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Survey of Practice Patterns in the Management of Strabismus in Pakistan  
glasses, optometric vision therapy including orthoptic  
exercises, injecting Botulinum toxin and surgery  
never considered reliable and more than one  
assessment  
was  
performed  
before  
surgery.  
including recession and resection procedures10,11,12  
.
Fundoscopy was performed by almost all the  
ophthalmologists. Percentage of ophthalmologists  
performing cycloplegic refraction was very low. Non  
surgical techniques used and their relative distribution  
is shown in Figure 1. Only 5 (6.57%) surgeons used  
Strabismus is both a social and pathological  
problem. It needs to be addressed and practiced in an  
organized and established manner. The main goal of  
our effort is to find out the current practice of  
management of strabismus and highlight the short  
comings being practiced. This will help in better  
management of strabismus. It is the need of hour to  
establish a consensual protocol for strabismus to be  
followed in the light of experiences of renowned  
ophthalmologist of the country.  
MATERIAL AND METHODS  
In order to design this study an extensive literature was  
reviewed regarding standard guidelines being followed  
in the best centers of the World. After having reviewed  
the current practices prevailing in different centers, a  
questionnaire was designed. This focused on common  
shortcomings and on standards being followed  
differently  
Ophthalmologists  
by  
different  
who were  
ophthalmologists.  
members of  
Ophthalmological Society of Pakistan (OSP), having  
their expertise in strabismus surgery for more than 5  
years and practicing Pediatric ophthalmology were  
selected. Those having less than 5 years’ experience  
was excluded from the study. This was sent through  
email and online to 90 renowned selected  
Ophthalmologists. This data was compiled, analyzed  
and was converted to a summary in points. Each point  
of that summary was discussed with 10 renowned  
ophthalmologists having their expertise in strabismus  
at one to one meetings held at conference of  
Ophthalmological Society of Pakistan (OSP).  
Fig. 1: Non-surgical Methods.  
adjustable sutures. Rest of 71 used non adjustable  
sutures in strabismus surgery (Figure 2). Almost all the  
RESULTS  
We contacted 90 ophthalmologists, out of whom 76  
responded to our Questionnaire. More than 90% (69)  
surgeons had an experience of more than ten years in  
squint surgery. Almost all the surgeons were also  
performing cataract surgery regularly. Oculoplastics  
was performed by 19 (25%) of them. Complete  
Orthoptic Assessment (sensory and Motor) was  
performed by only 46% (35) of the ophthalmologists.  
Prism cover test was used as a diagnostic tool by 70  
(92%) ophthalmologists. Rest of the ophthalmologists  
used Synoptophore with it. A single assessment was  
Fig. 2: Types of Sutures Used by the Surgeons.  
surgeons used to counsel about need for redo surgery.  
85% of surgeons were of the view that redo surgery  
was needed in almost 10 15% cases. Consecutive  
Pakistan Journal of Ophthalmology, 2020, Vol. 36 (2): 115-119  
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Nasir Ahmed, et al  
squint surgery was performed in less than 20%  
according to view of expert ophthalmologist. There  
were 96% ophthalmologists who performed surgery  
under general Anesthesia but only 46% of them  
explained the complications of Anesthesia (Figure 3).  
More than 90% of surgeons explained the surgical  
procedures being done, its complications, post-  
operative care and need to use glasses or need for  
orthoptic exercises. However only 30 (39.47%) of  
them also explained per-operative complications. All  
the surgeons kept follow up of the patients on 1st post-  
operative day.  
performed in every patient of suspected strabismus.  
Tejedor J et al assessed the applicability of prism  
cover test in quantifying the horizontal deviation and  
found it to be useful in measuring the deviation15. De  
Jongh16 E et al compared the difference of prism cover  
test measurement between four examiners and found  
that a difference of more than 10 prism diopter is due  
to inter-observer variability. However, they  
emphasized upon the importance of orthoptic  
assessment for accurate measurement of deviation.  
Complete orthoptic assessment was performed by only  
46% of the experts. Our panel discussed it and  
finalized the recommendation of complete Orthoptic  
assessment in all the patients. Half of the  
ophthalmologists had the assessment done by both the  
surgeon and the orthoptist.  
Cycloplegic refraction was a neglected step, not  
being taken by the surgeons participating in the study.  
Only 18% of our study participants had incorporated it  
into their practice. Leffler CT17 and associates studied  
the success rates of strabismus surgery comparing  
adjustable versus conventional suture techniques. They  
concluded that adjustable suture technique was  
associated with less re-operation rate than  
conventional suture technique in cases of horizontal  
strabismus while the converse was true for vertical  
strabismus surgery. Kamal AM et al compared the  
adjustable versus non-adjustable sutures in paediatric  
horizontal strabismus surgery. While finding no  
significant difference in maneuvering the two  
techniques, they concluded that adjustable suture  
technique was associated with better success rates18.  
Goerg TVKG19 published a case series about the  
use of botulinum toxin in patients diagnosed with  
cyclic strabismus. They recommended the use of  
botulinum toxin in those patients of alternate  
strabismus who have undergone at least one-month  
trial of prismatic correction for phoric angle. Saunte  
JP20 et al administered botulinum toxin in patients of  
intermittent exotropia and after one-month post  
injection, they found a significant reduction in the  
deviation and an improvement in the reading  
symptoms.  
Fig. 3: Patient Counselling.  
DISCUSSION  
Strabismus is actually a condition in which two eyes  
are not in accord with each other, setting a stage for  
developing amblyopia, double vision, abnormal head  
posture. There are various treatment modalities for its  
management, which include; use of patches, prism  
glasses, orthoptic exercises and botulinum toxin  
injection. Yilmaz et al13 studied the effect of prism  
cover test on the post-operative outcomes in patients  
of strabismus. They found that the surgical outcomes  
with and without prism cover test lead to a successful  
motor alignment in 80% of cases. However, they were  
of the opinion that prism cover test may lead to a  
better functional result13. Hatt SR and colleagues  
studied the importance of deviation measurement in  
patients of intermittent exotropia and they urged upon  
the repeatability of prism cover test measurement in  
order to get an accurate measurement and detect any  
significant change in deviation14. In our study, most  
common symptom of Strabismus, which was  
encountered by more than 90% of the  
ophthalmologists was misalignment of eyes and was  
confirmed with prism cover test. Our panel  
recommended this test for diagnostic purposes to be  
Other methods to correct strabismus were  
orthoptic exercises, refraction, botulinum injection and  
glasses. Most of the surgeons used combination of  
these treatments. Our Panel suggested an amalgam of  
these measures to be taken before progressing to  
surgery. A huge percentage of the surgeons (more than  
90%) explained redo surgery and its post-operative  
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Survey of Practice Patterns in the Management of Strabismus in Pakistan  
white preschool children: Multiethnic pediatric eye  
disease study. Ophthalmology, 2013; 120 (10): 2117-  
2124.  
complications including under correction and over  
correction in detail to the patient. The percentage of  
redo surgery was found almost 10-15%, which is still a  
higher percentage. Better pre-operative assessment,  
pre-operative use of non-surgical measures and  
education of patients can reduce the incidence of redo  
strabismus surgery. In our study, less than 50%  
surgeons explain complications of anesthesia. We lay  
2. Graham PA. Epidemiology of strabismus. Br J  
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5. Hatt SR, Leske DA, Kirgis PA, Bradley EA, Holmes  
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The limitation of our study was it only included  
those ophthalmologists who were members of  
Ophthalmological Society of Pakistan. In future a  
study involving more ophthalmologists and further  
aspects related to strabismus need to be studied in  
order to improve standard of care provided by health  
professionals.  
CONCLUSION  
The current practices in strabismus need to be  
standardized and a consensus should be developed at a  
national level.  
Ethical Approval  
The study was approved by the Institutional review  
board/Ethical review board.  
orthoptic exercise program.  
J Am Assoc Pead  
Conflict of Interest  
Authors declared no conflict of interest  
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11. Biglan, A.W., Burnstine RA, Rogers GL, Saunders  
RA. Management of strabismus with botulinum a toxin.  
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Author’s Designation and Contribution  
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H. Preliminary report: Prescription of prism glasses by  
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impact of prism adaptation test on surgical outcomes in  
patients with primary exotropia. Clin and Exp  
Optometry, 2015; 98 (3): 224-227.  
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Holmes JM. Variability of angle of deviation  
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Ch Nasir Ahmed; Associate Professor: Research idea  
conception, data collection and analysis, article  
writing.  
Muhammad Shaheer; Assistant Professor: Literature  
search and data analysis, editing article draft.  
Sarmad Zahoor; Data collection and analysis.  
Salman Hamza; Assistant Professor: Data collection  
and analysis.  
Samran Asim; Post graduate Resident: Literature  
search, Final review  
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