• Users Online: 154
  • Home
  • Print this page
  • Email this page
Home Current issue Ahead of print Search About us Editorial board Archives Submit article Instructions Subscribe Contacts Login 

 Table of Contents  
ORIGINAL ARTICLE
Year : 2017  |  Volume : 110  |  Issue : 3  |  Page : 89-93

Correlation between the axial length and the effect of recession of horizontal rectus muscles


Department of Ophthalmology, Faculty of Medicine, Zagazig University, Zagazig, Egypt

Date of Submission05-May-2017
Date of Acceptance09-Jul-2017
Date of Web Publication6-Nov-2017

Correspondence Address:
Manar A Ghali
Department of Ophthalmology, Faculty of Medicine, Zagazig University, Zagazig
Egypt
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/ejos.ejos_31_17

Rights and Permissions
  Abstract 

Purpose
The aim of this study is to determine whether the axial length (AxL) measurement would be useful in predicting the effect of horizontal rectus muscles recession.
Patients and methods
This study retrospectively reviewed 94 patients (52 with intermittent exotropia and 42 with infantile esotropia and partially accommodative esotropia), with age ranging from 4 to 15 years (7.63±3.2). All cases underwent bilateral lateral rectus recession for exotropia and bilateral medial recession for esotropia; there were no cases of combined vertical strabismus. There was no history of any ocular trauma or previous strabismus surgery. Preoperative angle of deviation, AxL (IOL Master), and postoperative angle of deviation at 6 months were recorded; effect of recession was calculated in all cases.
Results
The mean AxL for all cases was 23.39±1.73. The patients were divided into two groups: exotropia group (n=52) and esotropia group (n=42). Each group was subdivided into two subgroups: subgroup I (AxL<23.39) and subgroup II (AxL≥23.39). The effect of recession in exotropic group was 2.27±0.29; in short AxL subgroup, it was 2.42±0.17, and in long AxL subgroup, it was 1.98±0.25. In esotropic group, the effect of recession was 3.36±0.53; in subgroup I, it was 3.67±0.31, and in subgroup II, it was 2.87±0.44.
Conclusion
The results showed a negative correlation between AxL and effect of recession in both esotropia and exotropia groups. It is recommended to increase the amount of recession in longer AxL.

Keywords: axial length, effect of recession, infantile esotropia, intermittent exotropia, strabismus surgery


How to cite this article:
Ghali MA. Correlation between the axial length and the effect of recession of horizontal rectus muscles. J Egypt Ophthalmol Soc 2017;110:89-93

How to cite this URL:
Ghali MA. Correlation between the axial length and the effect of recession of horizontal rectus muscles. J Egypt Ophthalmol Soc [serial online] 2017 [cited 2017 Dec 18];110:89-93. Available from: http://www.jeos.eg.net/text.asp?2017/110/3/89/217698


  Introduction Top


The success of strabismus surgery is influenced by a number of preoperative factors [1],[2]. The results of surgery showed great variability among patients. The investigation of preoperative and intraoperative factors would help in planning a surgical intervention [3].

Bateman et al. [4] analyzed variables such as age of onset of deviation, age at surgery, interval between onset of deviation and surgery, and accommodative convergence to accommodation (AC/A) ratio. Among those variables, preoperative deviation was found to be the strongest predictor for both patients with esotropia and those with exotropia [3].

Kushner and Vrabec [5] reported evidence that response to strabismus surgery should correlate with axial length (AxL). Kushner et al. [6] reported significant negative correlation between AxL and response for patients with esotropia and poor correlation for patients with exotropia.

Rah et al. [7] concluded that in long eyes, the surgical outcome of horizontal recti recession seems to be poor than short eyes in both esotropia and exotropia.

Galantuomo et al. [8] showed that recession of extraocular muscles is more effective in larger eyes than in small ones.

Because of this controversy in results between previous authors, our study aimed at assessing the influence of AxL on the surgical outcome of horizontal recti recession in children.


  Patients and methods Top


This was a retrospective study that reviewed 94 patients with horizontal strabismus who underwent horizontal rectus recession in the period from January 2014 to June 2015 in the ophthalmology department of Zagazig University. Institutional review board approval for this study was obtained from Faculty of Medicine, Zagazig University.

The patients’ ages ranged from 4 to 15 (7.63±3.2) years. The patients were divided into exotropia group (n=52), all of them having intermittent exotropia, and esotropia group (n=42), all of them being cases of infantile esotropia and partially accommodative type with normal AC/A ratio. Only patients who underwent symmetric bilateral recessions were included. All patients did not have combined vertical deviation with no history of any ocular trauma, previous squint surgery, and systemic diseases that could interfere with motility or amblyopia. Patients with anisometropia (>two-diopters difference between both eyes) and large angle of preoperative deviation of more than 55Δ were excluded.

Complete ophthalmological examination included measuring preoperative angle of deviation at near and distance with the alternate prism and cover test when possible, and when not possible, using the Krimsky method while wearing their full corrective spectacles. AxL measurement using IOL Master (Carl Zeiss, Jena, Germany) was done for all patient preoperatively. Patients with AxL difference between both eyes of more than 0.5 mm were excluded.

All patients underwent bilateral symmetric recessions surgery by the same surgeon (M.A.G.) to correct squint under general anesthesia based on surgical planning table, which is based on corrective previous tables according to surgeon experience ([Table 1]).
Table 1 Amount of bilateral recession in both eotropia and exotropia groups

Click here to view


In all operations, we performed the anchor hang-back technique for muscle recession. Conjunctival limbal incision was made, and the muscle insertion was exposed after dissection of intermuscular septum and hooked, then the insertion was secured with 6/0 polyglactin (vicryl) double armed sutures (Ethicon Inc., Somerville, New Jersey, USA). Scleral bites were taken at the decided site of recession on each side of the muscle and then the muscle was disinserted, and the vicryl sutures were taken again and secured to muscle insertion and tied. Conjunctiva was sutured with 7/0 vicryl (Ethicon Inc.).

All cases were followed up for at least 6 months postoperatively. The postoperative angle of deviation was measured with the same preoperative corrective spectacles, and the effect of recession was calculated for them at the end of follow-up period. The effect of recession is the difference between postoperative and preoperative angle divided by total amount of recession.

The collected data were coded and analyzed using SPSS (SPSS Inc, IBM company, Chicago, USA), and the level of significance was set at P value less than 0.05. The power of study was at 80–95% confidence interval. Mean, median, SD, and range were used for quantitative data summarization, and Student’s t-test and Mann–Whitney U-test were performed for their analysis. For qualitative data summarization, number and percentage were used, and χ2-test was performed for analysis. Pearson correlation coefficient (r) was used to study association between mean dose response (MDR) and AxL, and logestic linear regression was used to predict the value of MDR from angle deviation and AxL.


  Results Top


A total of 94 patients (65 females and 29 males) were recruited in this study, and their mean age was 7.63±3.2 years. The patients were divided into two groups: exotropia group (n=52) and esotropia group (n=42). Demographics of patients are summarized in [Table 2]. No significant statistical difference was found between both groups regarding preoperative data, except for age.
Table 2 Demographics of the patient

Click here to view


The mean AxL of all patients was 23.39±1.73, and according to this mean, we subdivided both groups into subgroup I (AxL<23.39) and subgroup II (AxL≥23.39). In exotropia group, subgroup I had 34 patients whereas in subgroup II 18 patients were present; in esotropia group, subgroup I constituted 26 patients whereas subgroup II included 16 patients. The angle of deviation and AxL in exotropia and esotropia groups at 6 months postoperatively are shown in [Table 3].
Table 3 Axial length and angle of deviation of both groups at 6 months postoperatively

Click here to view


The effect of recession in exotropia at 6 months was 2.27±0.29; in subgroup I, it was 2.42±0.17, whereas in subgroup II, it was 1.98±0.25, with significant difference between subgroups I and II (P<0.05).

The effect of recession in esotropia at 6 months was 3.36±0.53; in subgroup I, it was 3.67±0.31, whereas in subgroup II, it was 2.87±0.44, with no significant difference between subgroups I and II (P<0.05).

The effect of recession of both groups is shown in [Table 4].
Table 4 Effect of recession of both groups at 6-month postoperative visit

Click here to view


[Table 5] and [Table 6] and [Figure 1], [Figure 2], [Figure 3], [Figure 4] show the correlation and regression analysis between MDR and both AxL and preoperative angle in both groups.
Table 5 Correlations between the MDR and preoperative angle and axial length

Click here to view
Table 6 Correlations between MDR and axial length and preoperative angle in both groups

Click here to view
Figure 1 Correlation between axial length and mean dose response (MDR) in exotropia group.

Click here to view
Figure 2 Correlation between axial length and mean dose response (MDR) in esotropia group.

Click here to view
Figure 3 Correlation between preoperative angle and mean dose response (MDR) in exotropia group.

Click here to view
Figure 4 Correlation between preoperative angle and mean dose response (MDR) in esotropia group.

Click here to view



  Discussion Top


Most surgical formulas for the management of strabismus use the number of millimeters of muscles recession solely on the preoperative angle of deviation [9],[10].

Although some researchers tested a surgical formula that took AxL into account [11],[12],[13]. Yet there is still controversy about its effect on results of recessions in both esotropia and exotropia.

We excluded patients with high AC/A ratio and nonaccommodative convergence excess, as previous studies have shown that the response of surgery is influenced by the amount by which the near esotropia exceeded the distance exotropia [14].

Anchor hang-back recession surgical technique was performed in all cases, as it is safe and provides the most accurate results with the least amount of complications according to our experience.

In this study, the mean AxL was 23.39±1.73, which is comparable with previous study of Rah et al. [7], in which the AxL was 23.21±1.38.

There was a negative correlation between both AxL and effect of recession in both groups (esotropic and exotropic), which did not agree with the results of Kushner et al. [6] who reported a negative correlation in esotropic but not in exotropic group. This difference in results may be attributed to that in our study there was no significant difference between esotropic and exotropic groups regarding AxL (23.32±1.69 vs. 23.4±1.78), whereas in the study by Kushner and colleagues, there is a statistical difference, as the esotropic group has relatively lesser mean AxL, which made their results unfair.

However, the results obtained in this work agreed with those of Rah et al. [7] who reported negative correlation in both groups. This agreement is mainly because in both studies the AxL of both groups was nearly comparable.

Correlation analysis in both groups showed negative correlation between AxL and effect of recession (MDR) and positive correlation between preoperative angle and MDR.

For each group, a formula was concluded to predict the effect of recession and therefore recommend amount of recession needed for each AxL.

In exotropia: MDR=4.28−(0.11×AxL)+(0.019×preoperative angle).

So if the preoperative angle was 30 prism diopter (PD) and the AxL was 23 mm, MDR will be 2.32 PD/mm, which means that we need to recess each lateral rectus 6.5 mm, whereas if the same preoperative angle exists in patient with AxL 26 mm, MDR will be 1.99, which means that we have to recess each lateral rectus by 7.5 mm.

In esotropia: MDR=4.93−(0.091×AxL)+(0.016×preoperative angle).

So if the preoperative angle was 30 PD and the AxL was 23 mm, MDR will be 3.32 PD/mm, which means that we need to recess each medial rectus 4.5 mm, whereas if the same preoperative angle exists in patient with AxL 26 mm, MDR will be 3 PD/mm, which means that we have to recess each medial rectus by 5 mm.

Glantuomo et al. [8] reported positive correlation between AxL and effect of recession in patients with exotropia, which completely disagreed with our results. This may be attributed to the small sample size they investigated (only 28 patients) and the short follow-up period of 3 months.

Intraoperative biometry could prevent errors of AxL measurements caused by restlessness, so it leads to more accurate surgery [15].

This study had some limitations: small sample size, the relatively short follow-up period, and we did not measure either the limbus insertion distance or the tendon width of the muscles, which were reported to affect the results in previous studies [16],[17].

More future studies with larger sample size and longer follow-up periods taking other factors in account need to be done.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 
  References Top

1.
Scott AB, Mash AJ, Jampolsky A. Quantitative guidelines for exotropia surgery. Invest Ophthalmol 1975; 14:428–36.  Back to cited text no. 1
    
2.
Von Noarden G. Principles of surgical treatment. In: Klen EA, editor. Binocular vision and ocular motility. 3rd ed. St Louis, MO: CV Mosby; 1985. pp. 440–479.  Back to cited text no. 2
    
3.
Abbasoglu OE, Sener EC, Sanac AS. Factors influencing the successful outcome and response in strabismus surgery. Eye 1996; 10:315–320.  Back to cited text no. 3
[PUBMED]    
4.
Bateman B, Parks M, Wheeler N. Discriminant analysis of acquired esotropia surgery. Ophthalmology 1983; 90:1145–1149.  Back to cited text no. 4
    
5.
Kushner BJ, Vrabec M. Theoretical effects of surgery on length-tension relationships in extraocular muscles. J Pediatr Ophthalmol Strabismus 1987; 24:126–131.  Back to cited text no. 5
[PUBMED]    
6.
Kushner BJ, Lucchese NJ, Moton GV. The influence of axial length in the response to strabismus surgery. Arch Ophthalmol 1989; 107:1616–1618.  Back to cited text no. 6
    
7.
Rah SH, Lee W, Kim S, Han SH. Effects of axial length on the horizontal recti recession in children with horizontal strabismus. Invest Ophthalmol Visual Sci 2010; 31:3013.  Back to cited text no. 7
    
8.
Galantuomo MS, Fossarello M, Guccu A, Zucca I. The role of eye axial length in panning strabismus surgery. Invest Ophthalmol Visual Sci 2013; 54:4707.  Back to cited text no. 8
    
9.
Scott WE, Reese PD, Hirsch CR, Flabetich CA. Surgery for large angle esotropia two vs three and four horizontal muscles. Arch Ophthalmol 1986; 104:374–377.  Back to cited text no. 9
    
10.
Nelson LB, Wagner RS, Simon JW, Harley R. Congenital esotropia. Surv Ophthalmol 1987; 31:363–383.  Back to cited text no. 10
    
11.
Gillies WE, Mc Indoe A. The use of ultrasonography in determining the amount of extraocular muscle surgery in strabismus. Aust J Ophthalmol 1982; 10:191–194.  Back to cited text no. 11
    
12.
Gillies WE, Mc Indoe A. The use of A scan ultrasonography to design the strabismus operation. In: Reinecke RD, editor. Strabismus. New York, NY: Grane & Stralton; 1984. pp. 659–687.  Back to cited text no. 12
    
13.
Gillies WE, Hughes A. Results in 50 cases of strabismus after graduated surgery designed by A scan ultrasonography. Br J Ophthalmol 1984; 68:790–795.  Back to cited text no. 13
    
14.
Kushner BJ, Presian MW, Morton GV. Treatment of partly accommodative esotropia with a high accommodative convergence-accommodation ratio. Arch Ophthalmol 1987; 105:815–818.  Back to cited text no. 14
    
15.
Perisutti P, Vinciguerra A, Pensiero S. Intraoperative axial length biometry in esotropia surgery. Ultrasonography in Ophthalmology XV. The documenta ophthalmologica proceedings series, Cortina, Italy; 1997. pp. 457–463.  Back to cited text no. 15
    
16.
Lee JY, Lee EJ, Park KA, Oh SY. Correlation between the limbus insertion distance of the lateral rectus muscle and lateral rectus recession surgery in intermittent exotropia. PloS One 2016; 11:e0160263.  Back to cited text no. 16
    
17.
Lee H, Kim SH. Bilateral lateral rectus recession considering the tendon width in intermittent exotropia. Eye (Lond) 2009; 23:1808–1811.  Back to cited text no. 17
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]



 

Top
 
 
  Search
 
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

 
  In this article
Abstract
Introduction
Patients and methods
Results
Discussion
References
Article Figures
Article Tables

 Article Access Statistics
    Viewed103    
    Printed2    
    Emailed0    
    PDF Downloaded21    
    Comments [Add]    

Recommend this journal


[TAG2]
[TAG3]
[TAG4]