Graefes Arch Clin Exp Ophthalmol DOI 10.1007/s00417-015-2992-4
PEDIATRICS
Medial rectus muscle elongation, a technique to treat very large-angle esotropia Ahmad Ameri 1 & Mohammad Reza Akbari 1 & Ali Reza Keshtkar Jaafari 1 & Masoud Aghsaei Fard 1 & Bahram Eshraghi 1 & Vida Tavakoli 1 & Arash Mirmohammadsadeghi 1
Received: 29 December 2014 / Revised: 6 March 2015 / Accepted: 13 March 2015 # Springer-Verlag Berlin Heidelberg 2015
Abstract Purpose The purpose was to describe the medial rectus muscle elongation (MRE) procedure to treat very largeangle esotropia (ET) with surgery on a lower number of muscles. Methods Twenty patients with very large-angle ET (more than 70 PD) underwent the MRE procedure. In the MRE procedure, the muscle was split longitudinally into three parts. The wider central part was sutured with 6/0 vicryl and disinserted. The distal end of the peripheral parts (still attached to the original insertion), 7-9 mm away from the insertion, was sutured to the proximal end of the central part. At the end of the procedure, the distance of the anastomosis site from the insertion was named as the final elongation. The doseresponse effect of the final elongation was calculated in bilateral MRE cases. The mean of the dose-response effect, obtained in the binocular surgery group, was used in the monocular surgery group to calculate the resection effect of lateral rectus (LR) muscle. Results Eleven patients underwent bilateral MRE and nine patients underwent unilateral MRE and LR muscle resection. The mean preoperative far and near deviation was 94.10± 19.33 PD. The mean postoperative deviation was 14.60± 18.07 PD for far and 14.50±18.23 PD for near deviation. In
* Arash Mirmohammadsadeghi [email protected] 1
Farabi Eye Research Center, Tehran University of Medical Sciences, Tehran, Iran
bilateral MRE cases, the mean dose-response effect of the elongation was 5.53±0.67 PD/mm for far and 5.58±0.69 PD/mm for near deviation. The mean LR muscle resection effect was 6.41±1.99 PD/mm for far and 6.28±1.93 PD/mm for near deviation. Conclusion The MRE procedure seems an acceptable method to treat very large-angle ET with surgery on a lower number of muscles.
Keywords Medial rectus muscle . Rectus muscle elongation . Esotropia . Large-angle esotropia
Introduction The surgical treatment of very large-angle [>70 prism diopters (PD)] deviations has been a matter of debate for several decades [1–16]. According to the surgical dose tables (by Santiago and Rosenbaum), surgery on two horizontal rectus muscles corrects up to 50 PD of esotropia [17]. Millán and colleagues demonstrated that for deviations>65 PD, monocular recess-resect surgery did not result in a successful outcome [1]. So, for very large-angle deviations, most surgeons prefer to operate on the third or even fourth muscles. Since the advent of strabismus surgery, the surgeons attempted to correct a higher amount of deviation with surgery on a lower number of muscles. The strabismus surgery on a lower number of muscles is a logical concept because of decreased operating time and the preserved ciliary circulation. To decrease the number of operated muscles in very large-angle deviations, different plans and procedures
Graefes Arch Clin Exp Ophthalmol
were suggested [1–15]. Damanakis and colleagues performed an 8 mm bilateral medial rectus (MR) recession for children with 80-90 PD esotropia (ET) with successful surgical alignment in 75 % of cases [2]. The supramaximal recession and resection (more than the values in the surgical dose tables) were also performed in the studies of Gigante and Bicas [3], Li and Zhang [4], and Chang and colleagues [5] with a different number of operated muscles, variable results, and slight limitation in ductions. In the reoperations, marginal myotomy of the MR muscle was also performed to augment the effect of maximal recession [18]. Minguini and colleagues demonstrated good results with a combination of the recessresect procedure and botulinum toxin injection [6]. Similarly, Lueder and colleagues combined bilateral MR recession with botulinum toxin injection to treat large-angle infantile ET [7]. A few studies on elongation of the rectus muscles were performed to treat large-angle deviations [8–13]. Diamond [8] and Amitava et al. [9] used the resected part of the rectus muscle to elongate its antagonist. Esser and colleagues used the bovine pericardium to elongate the inferior rectus muscle in Graves’orbitopathy [10]. Sood and colleagues described a method for lengthening of rectus muscles with comparable results to the recession procedure [11]. In this study, the technique of the medial rectus elongation (MRE) was introduced instead of recession to treat very large-angle ET with surgery on a lower number of muscles.
Material and methods In this prospective study, approved before beginning the study by the institutional review board of the Farabi Eye Research Center, 20 patients diagnosed with very large-angle ET (70 PD or higher in far or near deviations) in 2008-2012 in the strabismus clinic of the Farabi Eye Hospital (Tehran-Iran) were included. The patients with a history of previous strabismus or retinal surgery, paretic or restrictive strabismus, vertical deviations more than 5 PD, central nervous system diseases (including cerebral palsy), and MR muscle width90 PD was due to this approach. The determination of the dose-response effect in the present study can help in better planning of future operations and finding a nomogram in the future studies. A few studies on large-angle deviations discussed the doseresponse effect of their procedure [8, 11]. In Diamond’s technique (transposition of the resected muscle segment to the antagonist muscle), each millimeter of alteration (recession + resection + lengthening- advancement) corrected about 4 PD of deviation [8]. In the Sood and colleagues’ technique (with the most similarities to our procedure), each millimeter of the effective lengthening in the MR muscle corrected about 2-3 degrees (3.5-5.25 PD) of ET [11]. The mean dose-response effect of the MRE technique in distance and near (5.53 and 5.58 PD/mm, respectively) was higher than those of the Sood and colleagues’ technique. Thus, this procedure might be more effective than Sood and colleagues’ procedure to treat very large-angle ET. In addition, the relatively small range of the dose-response effects (4.63-6.64 PD/mm) could increase the predictability of the MRE procedure. In the monocular surgery group, the LR muscle resection effect values were higher than expected in the conventional recess-resect procedure. If the LR muscle resection effect values were calculated with similar formula from the surgical dose tables [16], the results were between 2.1 and 2.8 PD/mm. But in the monocular surgery group in this study, the minimum of LR resection effect values was 3.61 PD/mm for distance and 3.56 PD/mm for near deviation. The mean of the LR resection effect values was 6.41 PD/mm for distance and 6.28 PD/mm for
Graefes Arch Clin Exp Ophthalmol
near deviation. This increased effect might be due to resection of the antagonist muscle against a muscle that weakened more than a conventional recession procedure. Consequently, when a strong muscle works against a weaker muscle, it gets stronger. So, the effect of the resection procedure may also exceed the expected values. As a result, probably, in contrast with binocular surgeries, the effect of the elongation procedure in monocular surgeries was not limited to the weakened muscle, and the increased effect of the resection might also play a role. The limitations of our study were low sample size, absence of the other deviation groups (such as exotropia), absence of the control group without elongation, and lack of preoperative and postoperative saccadic velocity measurements. In addition, the irreversible changes in the extraocular muscles may raise some issues about the real advantage of the procedure. Furthermore, the relatively large range of the achieved correction and resection effect values should also be considered in the planning of future studies. Studies with control groups and larger sample sizes must be done to refine the concepts. In conclusion, the introduced MRE procedure seems an acceptable method to treat very large-angle ET with a lower number of muscles. This procedure might be most advantageous in the patients with low visual acuity or prominent deviation in one eye that are unwilling to do the surgery on the healthy eyes. The MRE procedure showed the following benefits: no risk of scleral perforation, preserved integrity of the original insertion with availability for the recession or resection in the reoperations, and preserved arc of contact. In monocular MRE and LR resection operations, the increased LR muscle resection effect might play a role in the effects of this procedure. The effect of the elongation surgery on the other rectus muscles remains to be determined in future studies.
2.
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4. 5.
6.
7.
8. 9.
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11.
12. 13. 14.
15. Ethical standards The study was approved by the institutional review board of the Farabi Eye Research Center. The study and data collection were compliant with the principles of the Declaration of Helsinki. Informed consent was obtained from all patients.
16.
Conflict of interest The authors declare that they have no conflict of interest.
17.
References
18.
1.
Millán T, de Carvalho KM, Minguini N (2009) Results of monocular surgery under peribulbar anesthesia for large-angle horizontal strabismus. Clinics (Sao Paulo) 64:303–308
19.
Damanakis AG, Arvanitis PG, Ladas ID, Theodossiadis GP (1994) 8 mm bimedial rectus recession in infantile esotropia of 80-90 prism dioptres. Br J Ophthalmol 78:842–844 Gigante E, Bicas HE (2009) Monocular surgery for largeangle esotropias: a new paradigm. Arq Bras Oftalmol 72: 47–56 Li JH, Zhang LJ (2013) Three-muscle surgery for very large-angle constant exotropia. J AAPOS 17:578–581 Chang JH, Kim HD, Lee JB, Han SH (2011) Supermaximal recession and resection in large-angle sensory exotropia. Korean J Ophthalmol 25:139–141 Minguini N, de Carvalho KM, Bosso FL, Hirata FE, Kara-José N (2012) Surgery with intraoperative botulinum toxin-A injection for the treatment of large-angle horizontal strabismus: a pilot study. Clinics (Sao Paulo) 67:279–282 Lueder GT, Galli M, Tychsen L, Yildirim C, Pegado V (2012) Long-term results of botulinum toxin-augmented medial rectus recessions for large-angle infantile esotropia. Am J Ophthalmol 153: 560–563 Diamond GR (1990) True transposition procedures. J Pediatr Ophthalmol Strabismus 27:153–156 Amitava AK, Goswami AK, Mishra A (2005) Large-angle strabismus and primary true muscle transplantation. J Pediatr Ophthalmol Strabismus 42:211–215 Esser J, Schittkowski M, Eckstein A (2011) Graves' orbitopathy: inferior rectus tendon elongation for large vertical squint angles that cannot be corrected by simple muscle recession. Klin Monbl Augenheilkd 228:880–886 Sood GC, Malik SR, Gunguli G, Chowdhary S (1967) Lengthening of rectus muscles in strabismus surgery: with a description of a new muscle clamp. Br J Ophthalmol 51: 788–790 Hollwich F (1966) Technique and indication of tendon-lengthening by Gonin. Int Ophthalmol Clin 6:591–608 Kotania W, Binkiewicz E (1983) A new method of stratified elongation of the rectus muscle. Klin Ocz 85:91–92 Thomas S, Guha S (2010) Large-angle strabismus: can a single surgical procedure achieve a successful outcome? Strabismus 18: 129–136 Chatzistefanou KI, Ladas ID, Droutsas KD, Koutsandrea C, Chimonidou E (2013) Three horizontal muscle surgery for largeangle infantile or presumed infantile esotropia: long-term motor outcomes. JAMA Ophthalmol 131:1041–1048 Bayramlar H, Karadag R, Yildirim A, Oçal A, Sari U, Dag Y (2014) Medium-term outcomes of three horizontal muscle surgery in largeangle infantile esotropia. J Pediatr Ophthalmol Strabismus 3:160– 164 Santiago AP, Rosenbaum AL (1999) Surgical dose tables. In: Santiago AP, Rosenbaum AL (eds) Clinical strabismus management, principles and surgical techniques. WB Saunders, Philadelphia, pp 552–555 Kennedy JA (1970) Marginal myotomy of the medial rectus. Arch Ophthalmol 84:625–626 Agrawal S, Singh V, Gupta SK, Agrawal S (2013) Evaluating a new surgical dosage calculation method for esotropia. Oman J Ophthalmol 6:165–169
PEDIATRICS
Medial rectus muscle elongation, a technique to treat very large-angle esotropia Ahmad Ameri 1 & Mohammad Reza Akbari 1 & Ali Reza Keshtkar Jaafari 1 & Masoud Aghsaei Fard 1 & Bahram Eshraghi 1 & Vida Tavakoli 1 & Arash Mirmohammadsadeghi 1
Received: 29 December 2014 / Revised: 6 March 2015 / Accepted: 13 March 2015 # Springer-Verlag Berlin Heidelberg 2015
Abstract Purpose The purpose was to describe the medial rectus muscle elongation (MRE) procedure to treat very largeangle esotropia (ET) with surgery on a lower number of muscles. Methods Twenty patients with very large-angle ET (more than 70 PD) underwent the MRE procedure. In the MRE procedure, the muscle was split longitudinally into three parts. The wider central part was sutured with 6/0 vicryl and disinserted. The distal end of the peripheral parts (still attached to the original insertion), 7-9 mm away from the insertion, was sutured to the proximal end of the central part. At the end of the procedure, the distance of the anastomosis site from the insertion was named as the final elongation. The doseresponse effect of the final elongation was calculated in bilateral MRE cases. The mean of the dose-response effect, obtained in the binocular surgery group, was used in the monocular surgery group to calculate the resection effect of lateral rectus (LR) muscle. Results Eleven patients underwent bilateral MRE and nine patients underwent unilateral MRE and LR muscle resection. The mean preoperative far and near deviation was 94.10± 19.33 PD. The mean postoperative deviation was 14.60± 18.07 PD for far and 14.50±18.23 PD for near deviation. In
* Arash Mirmohammadsadeghi [email protected] 1
Farabi Eye Research Center, Tehran University of Medical Sciences, Tehran, Iran
bilateral MRE cases, the mean dose-response effect of the elongation was 5.53±0.67 PD/mm for far and 5.58±0.69 PD/mm for near deviation. The mean LR muscle resection effect was 6.41±1.99 PD/mm for far and 6.28±1.93 PD/mm for near deviation. Conclusion The MRE procedure seems an acceptable method to treat very large-angle ET with surgery on a lower number of muscles.
Keywords Medial rectus muscle . Rectus muscle elongation . Esotropia . Large-angle esotropia
Introduction The surgical treatment of very large-angle [>70 prism diopters (PD)] deviations has been a matter of debate for several decades [1–16]. According to the surgical dose tables (by Santiago and Rosenbaum), surgery on two horizontal rectus muscles corrects up to 50 PD of esotropia [17]. Millán and colleagues demonstrated that for deviations>65 PD, monocular recess-resect surgery did not result in a successful outcome [1]. So, for very large-angle deviations, most surgeons prefer to operate on the third or even fourth muscles. Since the advent of strabismus surgery, the surgeons attempted to correct a higher amount of deviation with surgery on a lower number of muscles. The strabismus surgery on a lower number of muscles is a logical concept because of decreased operating time and the preserved ciliary circulation. To decrease the number of operated muscles in very large-angle deviations, different plans and procedures
Graefes Arch Clin Exp Ophthalmol
were suggested [1–15]. Damanakis and colleagues performed an 8 mm bilateral medial rectus (MR) recession for children with 80-90 PD esotropia (ET) with successful surgical alignment in 75 % of cases [2]. The supramaximal recession and resection (more than the values in the surgical dose tables) were also performed in the studies of Gigante and Bicas [3], Li and Zhang [4], and Chang and colleagues [5] with a different number of operated muscles, variable results, and slight limitation in ductions. In the reoperations, marginal myotomy of the MR muscle was also performed to augment the effect of maximal recession [18]. Minguini and colleagues demonstrated good results with a combination of the recessresect procedure and botulinum toxin injection [6]. Similarly, Lueder and colleagues combined bilateral MR recession with botulinum toxin injection to treat large-angle infantile ET [7]. A few studies on elongation of the rectus muscles were performed to treat large-angle deviations [8–13]. Diamond [8] and Amitava et al. [9] used the resected part of the rectus muscle to elongate its antagonist. Esser and colleagues used the bovine pericardium to elongate the inferior rectus muscle in Graves’orbitopathy [10]. Sood and colleagues described a method for lengthening of rectus muscles with comparable results to the recession procedure [11]. In this study, the technique of the medial rectus elongation (MRE) was introduced instead of recession to treat very large-angle ET with surgery on a lower number of muscles.
Material and methods In this prospective study, approved before beginning the study by the institutional review board of the Farabi Eye Research Center, 20 patients diagnosed with very large-angle ET (70 PD or higher in far or near deviations) in 2008-2012 in the strabismus clinic of the Farabi Eye Hospital (Tehran-Iran) were included. The patients with a history of previous strabismus or retinal surgery, paretic or restrictive strabismus, vertical deviations more than 5 PD, central nervous system diseases (including cerebral palsy), and MR muscle width90 PD was due to this approach. The determination of the dose-response effect in the present study can help in better planning of future operations and finding a nomogram in the future studies. A few studies on large-angle deviations discussed the doseresponse effect of their procedure [8, 11]. In Diamond’s technique (transposition of the resected muscle segment to the antagonist muscle), each millimeter of alteration (recession + resection + lengthening- advancement) corrected about 4 PD of deviation [8]. In the Sood and colleagues’ technique (with the most similarities to our procedure), each millimeter of the effective lengthening in the MR muscle corrected about 2-3 degrees (3.5-5.25 PD) of ET [11]. The mean dose-response effect of the MRE technique in distance and near (5.53 and 5.58 PD/mm, respectively) was higher than those of the Sood and colleagues’ technique. Thus, this procedure might be more effective than Sood and colleagues’ procedure to treat very large-angle ET. In addition, the relatively small range of the dose-response effects (4.63-6.64 PD/mm) could increase the predictability of the MRE procedure. In the monocular surgery group, the LR muscle resection effect values were higher than expected in the conventional recess-resect procedure. If the LR muscle resection effect values were calculated with similar formula from the surgical dose tables [16], the results were between 2.1 and 2.8 PD/mm. But in the monocular surgery group in this study, the minimum of LR resection effect values was 3.61 PD/mm for distance and 3.56 PD/mm for near deviation. The mean of the LR resection effect values was 6.41 PD/mm for distance and 6.28 PD/mm for
Graefes Arch Clin Exp Ophthalmol
near deviation. This increased effect might be due to resection of the antagonist muscle against a muscle that weakened more than a conventional recession procedure. Consequently, when a strong muscle works against a weaker muscle, it gets stronger. So, the effect of the resection procedure may also exceed the expected values. As a result, probably, in contrast with binocular surgeries, the effect of the elongation procedure in monocular surgeries was not limited to the weakened muscle, and the increased effect of the resection might also play a role. The limitations of our study were low sample size, absence of the other deviation groups (such as exotropia), absence of the control group without elongation, and lack of preoperative and postoperative saccadic velocity measurements. In addition, the irreversible changes in the extraocular muscles may raise some issues about the real advantage of the procedure. Furthermore, the relatively large range of the achieved correction and resection effect values should also be considered in the planning of future studies. Studies with control groups and larger sample sizes must be done to refine the concepts. In conclusion, the introduced MRE procedure seems an acceptable method to treat very large-angle ET with a lower number of muscles. This procedure might be most advantageous in the patients with low visual acuity or prominent deviation in one eye that are unwilling to do the surgery on the healthy eyes. The MRE procedure showed the following benefits: no risk of scleral perforation, preserved integrity of the original insertion with availability for the recession or resection in the reoperations, and preserved arc of contact. In monocular MRE and LR resection operations, the increased LR muscle resection effect might play a role in the effects of this procedure. The effect of the elongation surgery on the other rectus muscles remains to be determined in future studies.
2.
3.
4. 5.
6.
7.
8. 9.
10.
11.
12. 13. 14.
15. Ethical standards The study was approved by the institutional review board of the Farabi Eye Research Center. The study and data collection were compliant with the principles of the Declaration of Helsinki. Informed consent was obtained from all patients.
16.
Conflict of interest The authors declare that they have no conflict of interest.
17.
References
18.
1.
Millán T, de Carvalho KM, Minguini N (2009) Results of monocular surgery under peribulbar anesthesia for large-angle horizontal strabismus. Clinics (Sao Paulo) 64:303–308
19.
Damanakis AG, Arvanitis PG, Ladas ID, Theodossiadis GP (1994) 8 mm bimedial rectus recession in infantile esotropia of 80-90 prism dioptres. Br J Ophthalmol 78:842–844 Gigante E, Bicas HE (2009) Monocular surgery for largeangle esotropias: a new paradigm. Arq Bras Oftalmol 72: 47–56 Li JH, Zhang LJ (2013) Three-muscle surgery for very large-angle constant exotropia. J AAPOS 17:578–581 Chang JH, Kim HD, Lee JB, Han SH (2011) Supermaximal recession and resection in large-angle sensory exotropia. Korean J Ophthalmol 25:139–141 Minguini N, de Carvalho KM, Bosso FL, Hirata FE, Kara-José N (2012) Surgery with intraoperative botulinum toxin-A injection for the treatment of large-angle horizontal strabismus: a pilot study. Clinics (Sao Paulo) 67:279–282 Lueder GT, Galli M, Tychsen L, Yildirim C, Pegado V (2012) Long-term results of botulinum toxin-augmented medial rectus recessions for large-angle infantile esotropia. Am J Ophthalmol 153: 560–563 Diamond GR (1990) True transposition procedures. J Pediatr Ophthalmol Strabismus 27:153–156 Amitava AK, Goswami AK, Mishra A (2005) Large-angle strabismus and primary true muscle transplantation. J Pediatr Ophthalmol Strabismus 42:211–215 Esser J, Schittkowski M, Eckstein A (2011) Graves' orbitopathy: inferior rectus tendon elongation for large vertical squint angles that cannot be corrected by simple muscle recession. Klin Monbl Augenheilkd 228:880–886 Sood GC, Malik SR, Gunguli G, Chowdhary S (1967) Lengthening of rectus muscles in strabismus surgery: with a description of a new muscle clamp. Br J Ophthalmol 51: 788–790 Hollwich F (1966) Technique and indication of tendon-lengthening by Gonin. Int Ophthalmol Clin 6:591–608 Kotania W, Binkiewicz E (1983) A new method of stratified elongation of the rectus muscle. Klin Ocz 85:91–92 Thomas S, Guha S (2010) Large-angle strabismus: can a single surgical procedure achieve a successful outcome? Strabismus 18: 129–136 Chatzistefanou KI, Ladas ID, Droutsas KD, Koutsandrea C, Chimonidou E (2013) Three horizontal muscle surgery for largeangle infantile or presumed infantile esotropia: long-term motor outcomes. JAMA Ophthalmol 131:1041–1048 Bayramlar H, Karadag R, Yildirim A, Oçal A, Sari U, Dag Y (2014) Medium-term outcomes of three horizontal muscle surgery in largeangle infantile esotropia. J Pediatr Ophthalmol Strabismus 3:160– 164 Santiago AP, Rosenbaum AL (1999) Surgical dose tables. In: Santiago AP, Rosenbaum AL (eds) Clinical strabismus management, principles and surgical techniques. WB Saunders, Philadelphia, pp 552–555 Kennedy JA (1970) Marginal myotomy of the medial rectus. Arch Ophthalmol 84:625–626 Agrawal S, Singh V, Gupta SK, Agrawal S (2013) Evaluating a new surgical dosage calculation method for esotropia. Oman J Ophthalmol 6:165–169
