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Comparison of different tendon transposition techniques for the treatment of monocular elevation deficiency type 2
Journal Pre-proof Comparison of different tendon transposition techniques for the treatment of monocular elevation deficiency type 2 Osman Bulut Ocak, MD, Asli Inal, MD, Ebru Demet Aygit, MD, Selcen Celik, MD, Serap Yurttaser Ocak, MD, Ceren Gurez, MD, Isil Basgil Pasaoglu, MD, Birsen Gokyigit, MD PII:
S1091-8531(19)30583-X
DOI:
https://doi.org/10.1016/j.jaapos.2019.09.015
Reference:
YMPA 3116
To appear in:
Journal of AAPOS
Received Date: 26 December 2018 Revised Date:
8 September 2019
Accepted Date: 22 September 2019
Please cite this article as: Ocak OB, Inal A, Aygit ED, Celik S, Ocak SY, Gurez C, Pasaoglu IB, Gokyigit B, Comparison of different tendon transposition techniques for the treatment of monocular elevation deficiency type 2, Journal of AAPOS (2020), doi: https://doi.org/10.1016/j.jaapos.2019.09.015. This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Copyright © 2019, American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.
Comparison of different tendon transposition techniques for the treatment of monocular elevation deficiency type 2 Osman Bulut Ocak, MD,a Asli Inal, MD,a Ebru Demet Aygit, MD,a Selcen Celik, MD,a Serap Yurttaser Ocak, MD,b Ceren Gurez, MD,a Isil Basgil Pasaoglu, MD,a and Birsen Gokyigit, MD,a Author affiliations: aUniversity of Health Sciences, Beyoğlu Eye Research and Training Hospital, İstanbul, Turkey; bUniversity of Health Sciences, Okmeydani Research and Training Hospital, İstanbul, Turkey Submitted December 26, 2018. Revision accepted September 23, 20 Correspondence: Osman Bulut Ocak, Strabismus Department, Beyoğlu Eye Research and Training Hospital, Bereketzade Mahallesi, Bereketzade Cami Sk. 2/4, 34437, Beyoğlu/İstanbul (email: [email protected]). Word count: 1,945 Abstract only: 241
Abstract Purpose To compare results of three different tendon transposition techniques (Knapp procedure and two modified techniques) for the treatment of type 2 monocular elevation deficiency (MED) patients. Methods The medical records of patients with MED type 2 operated on at a single institution from 2000 to 2016 were reviewed retrospectively. Patients were divided into three vertical transposition groups: (1) full tendon width, (2) augmented surgery; and (3) partial tendon width. Surgical success was defined as no severe limitation of upgaze, hypotropia of <6∆, and no hypertropia in primary position. Pre- and postoperative vertical deviations in the primary position and limitations in elevation levels were compared. Results A total of 39 patients were included. The pre- and postoperative deviations in the full-tendon group were 22.50∆ ± 4.17∆ and 3.50∆ ± 1.27∆, respectively; in the augmented surgery group, 23.75∆ ± 4.78∆ and 1.75∆ ± 1.14∆; and in the partial-tendon group, 20.50∆ ± 3.98∆ and 4.12∆ ± 2.78∆. Corrected vertical deviations were 19∆, 23∆, and 16∆, respectively. The pre- and postoperative limitation of elevations were −2.80 and −0.80 in the full-tendon group, −3.20 and −0.90 in the augmented surgery group, and −2.37 and −1.12 in the partial-tendon group. The preand postoperative vertical deviation improvements and limitations of elevation were statistically significant (P < 0.05) in all groups. Success was achieved in 29 patients (74%). Conclusions In this study cohort, all three procedures were reasonably effective in improving vertical deviations and limitation of elevation.
Monocular elevation deficiency (MED) was initially identified as paralysis of the superior rectus and inferior oblique muscles, or double elevator palsy.1 Restriction of the inferior rectus muscle was found to play an important role in the etiology, and MED has been classified into three subgroups2,3: type 1 is a restrictive form that affects the inferior rectus muscle; type 2 is a paretic form that affects superior rectus muscle; and type 3 is a combined form that affects both muscles.3-5 The standard surgical procedure for MED type 2 patients is full tendon width transposition of the medial rectus and lateral rectus muscles (Knapp procedure).6,7 Recently, different tendon transposition techniques have been described and found to be effective for correcting vertical deviations and improvement of limitation of elevation.8,9 The aim of the present study was to compare the effects of different tendon transposition techniques on the vertical deviation and limitation of elevation in MED type 2 patients. Subjects and Methods This study was approved by the local the Taksim Research and Training Hospital, Clinical Researchs Ethical Board. Data handling and study protocols were compliant with the principles of the Declaration of Helsinki. The medical records of MED patients who underwent strabismus surgery at University of Health Sciences Beyoğlu Eye Research and Training Hospital between 2000 and 2016 were retrospectively reviewed. Patients with type 2 MED who underwent tendon transposition surgery for the correction of hypotropia were included. Exclusion criteria were previous strabismus surgery, different ocular and neurological pathologies, and follow-up of <12 months. Sex, age, affected eye, and medical and family histories were recorded. All patients underwent complete ophthalmic and orthoptic examinations before and after surgeries, including
cycloplegic refraction with cyclopentolate 1%. Binocularity was assessed using the Titmus Fly test for near vision and the Worth 4-Dot test for distance vision. Abnormal head posture and ptosis/pseudoptosis were noted. Pre- and postoperatively, the distance vertical deviations were measured using the prism base cover test, with the prism bars placed on the paretic eye at a primary position. All deviations were measured with appropriate spectacle correction. Limitations of elevation were graded on a scale of 0 to −4, both before and after surgeries, with 0 indicating no limitation and −4 indicating no movement. Surgical Techniques All surgeries were performed under general anesthesia by the same surgeon (BG) using a limbal incision. Forced duction and exaggerated traction tests were performed preoperatively. Standard full-tendon transposition was performed as described by Knapp.10 A full tendon width supraplacement of the horizontal rectus muscles in a position adjacent to the corners of the insertion of the superior rectus muscle was performed. Horizontal rectus muscles were aligned with the spiral of Tillaux. Augmented tendon transposition surgery was performed as described by Snir and colleauges.8 In this procedure, after full tendon width transposition, the posterior fixation suture was anchored to the sclera 8 mm posterior to the insertion of the superior rectus muscle near the nasal and temporal borders, thereby fixing 25% of the belly of the transposed medial rectus muscle and the lateral rectus muscle adjacent to the superior rectus muscle and aligned with the spiral of Tillaux. Partial tendon width transposition was performed as described by Kamlesh and colleagues.9 Transposition of equally divided (up to 15 mm) horizontal rectus muscles and the superior part of these muscles were transposed to the nearby insertion of the superior rectus
muscle aligned with the spiral of Tillaux. The full-tendon technique was used in all patients between 2000 and 2003. The surgical technique was decided according to vertical deviation measurements between 2003 to 2005. In 2003, full tendon width transposition was performed on patients with deviation of >25∆ and partial tendon width transposition was performed on patients with deviation of ≤25∆, following the recommendations of Kamlesh and colleagues.9 With publication of the augmented tendon transposition technique in 2005,8 the surgical technique was determined according to vertical deviations and limitations of elevation. In their study, vertical deviation of approximately 18∆ was corrected with surgery; the authors also found that limitation of elevation decreased more using augmented surgery than in did with unaugmented full tendon width transposistion.8 Accordingly, after 2005 full tendon with surgery was chosen for patients with deviation of 18∆ and limitation of elevation levels of −2; partial tendon width surgery, for patients with deviation of <18∆; and augmented transposition surgery, for all patients with deviation >25∆. Patients with −2 and −3 limitation of elevation and vertical deviations between 18∆ and 25∆ underwent augmented transposition surgery. Surgical success was defined as no severe limitation (−3 or −4), hypotropia of <6∆, and no hypertropia in primary position. Surgical complications were noted. Statistical analyses were performed with the e-PICOS program. Comparisons of pre- and postoperative values for each procedure were evaluated using the Wilcoxon test. P values of <0.05 were considered statistically significant. Results A total of 39 patients diagnosed with type 2 MED who underwent surgery met inclusion criteria. The epidemiology, clinical features, and pre- and postoperative vertical deviation means of all
patients are shown in Table 1. The mean hypotropia at distance before surgery was 22.73∆ ± 4.60∆ (range, 14∆-30∆); at final follow-up, 3.30∆ ± 2.80∆ (range, 0∆-10∆). The mean corrected vertical deviation was 19.43∆ ± 1.80∆ at distance. Pre- and postoperative vertical deviations of all patients are shown in Figure 1. We achieved surgical success in 29 cases (74%) after a single surgery. Postoperatively, the mean elevation deficit decreased from −2.82 ± 0.75 (range, −2 to −4) to −0.94 ± 0.84 (range, 0 to −2). Comparing pre- and postoperative values, all parameters were found to differ significantly (P < 0.05 [Wilcoxon test]). Surgical results are shown in Table 2. No postoperative complications (eg, anterior segment ischemia) were noted. Diplopia was not found because of absence of stereopsis, suppression, or amblyopia. No gain in stereopsis was noted. Anomalous head position improved but was not eliminated because of residual limitations of elevation and ptosis. The mean followup time was 26.14 ± 6.76 months (range, 20-40 months). The full-tendon technique was performed in 21 patients, with surgical success in 15 (71%). The mean vertical deviation in this group was 22.50∆ ± 4.17∆ (range, 14∆-30∆) preoperatively; 3.50∆ ± 1.27∆ (range, 0∆-12∆), postoperatively. Mean corrected vertical deviation was 19∆. The mean limitation of elevation was −2.80 ± 0.74 (range, −2 to −4) preoperative; −0.80 ± 0.64 (range, 0 to −2), postoperatively. See Table 2. Improvement in limitation in elevation and vertical deviation were significant (P < 0.05 [Wilcoxon test]). Six patients did not achieve surgical success; the mean vertical deviation in these patients was 26.12∆ ± 5.26∆. One patient had a reduction of limitation of downgaze to −1 after surgery, from no preoperative limitation. Ten patients were included in the augmented surgery group; all but 1 did not achieve
surgical success. The mean pre- and postoperative vertical deviations were 23.75∆ ± 4.78∆ and 1.75∆ ± 1.14∆, respectively. Mean correction was 22∆. Mean limitation of elevation was −3.20 ± 0.78 preoperatively and −0.90 ± 0.73 postoperatively (Table 2). All changes were statistically significant (P < 0.05 [Wilcoxon test]). One patient who failed had a deviation of 30∆ before surgery and 8∆ after. In 2 patients (20%) limitation of downgaze was reduced to −2 after surgery. Also, there was no hypertropia in primary position for these 2 patients. Eight patients were included the partial-tendon group, of whom 5 (63%) had surgical success. The mean vertical deviations were 20.50∆ ± 3.98∆ (range, 14∆-25∆) preoperatively and 4.12∆ ± 2.78∆ (range, 0∆-10∆) postoperatively. Mean corrected prism diopters was 16.38∆ (Table 2). Change in vertical deviation postoperatively were found significantly different. The change in limitation of elevation postoperatively was also significantly different (P < 0.05 [Wilcoxon test]); however, limitation of elevation levels were higher than in the other transposition techniques (−2.37 ± 0.51 to −1.12 ± 0.99) after surgery. In 4 patients (50%) limitation of elevation was −2 after surgery. No patient complained about limitation of elevation. No limitation of downgaze was been noted. Discussion In our study cohort, superior rectus paralysis without inferior rectus restriction was the main etiopathology of MED type 2 (supranuclear paralysis),3 which is typically treated using the Knapp procedure.6,7 This procedure corrects hypotropia and improves limitation of elevation7,11; however, results are unpredictable.6,12 We evaluated the efficacy of the standard Knapp procedure, augmented transposition surgery, and partial-tendon surgery for hypotropia and limitation of elevation in patients with MED type 2. Analysis of the published results of full-tendon transposition are shown in Table 3. In the
literature, the average vertical correction is variable, ranging from 9∆ to 40∆. In the current study, the average corrected vertical deviation was 19∆ using this technique. Improvement in limitation of elevation was also variable. Luo and colleagues13 found a 1.69 ± 0.87 improvement in elevation. Li and colleagues14 reported that the corrected vertical deviation was 28∆, and improvement in elevation was 1.90 ± 0.60. We found an improvement of 2.00 ± 0.10 in elevation. Snir and colleagues8 found that augmented tendon transposition was more effective than the full-tendon technique in correcting vertical deviation and limitation of elevation. Luo and colleagues13 reported a vertical deviation correction of 34∆ and improvement of 1.80 ± 0.45 in limitation of elevation. Li and colleagues14 found limitations of downgaze in all of their 8 patients but did not observe diplopia in the reading position. In the current study, we found an improvement of 2.30 ± 0.05 in elevation in 2 of 10 patients who had −2 limitation of downgaze, but because of deep amblyopia and loss of binocularity, no diplopia on downgaze occurred. Partial-tendon surgery also allowed for correction of horizontal strabismus in the paretic eye during same session.9 Kamlesh and Dadeya9 reported vertical and horizontal corrections of 25∆ and 20∆, respectively in vertical and horizontal corrections and horizontal corrections and significant improvement in elevation. We found a 16.38∆ correction in vertical deviations and 1.24 ± 0.48 improvement in elevation. We did not perform simultaneous horizontal strabismus surgery in our patients. The major limitation of this study is its retrospective design. A study strength is that the relatively long study period of more than 16 years. Because of the retrospective design of the study, surgical selections were variable by years, and we could not homogenize and randomize the group characteristics.
References 1.
White JW. Paralysis of the superior rectus muscle. Trans Am Ophthalmol Soc 1933;31:551-84.
2.
Scott WE, Jackson OB. Double elevator palsy: the significance of inferior rectus restriction. Am Orthopt J 1977;27:5-10.
3.
Raab EL, Abay AA, Bloom JN, Edmond JC, Lueder GT. Pediatric Ophthalmology and Strabismus. San Francisco, CA; American Academy of Ophthalmology; 2010:128-29.
4.
Ocak OB, Inal A, Aygit ED, et al. Surgical management in type 1 monocular elevation deficiency. J Pediatr Ophthalmol Strabismus 2018;55:369-74.
5.
Bagheri A, Sahebghalam R, Abrishami M. Double elevator palsy, subtypes and outcomes of surgery. J Ophthalmic Vis Res 2008;3:108-13.
6.
Burke JP, Ruben JB, Scott WE. Vertical transposition of the horizontal recti (Knapp procedure) for the treatment of double elevator palsy: effectiveness and long-term stability. Br J Ophthalmol 1992;76:734-7.
7.
Yurdakul NS, Ugurlu S, Maden A. Surgical treatment in patients with double elevator palsy. Eur J Ophthalmol 2009;19:697-701.
8.
Snir M, Friling R, Kalish-Stiebel H, Bourla D, Weinberger D, Axer-Siegel R. Combined rectus muscle transposition with posterior fixation sutures for the treatment of doubleelevator palsy. Ophthalmology 2005;112:933-8.
9.
Kamlesh DS. Surgical management of unilateral elevator deficiency associated with horizontal deviation using a modified Knapp’s procedure. Ophthalmic Surg Lasers Imaging 2003;34:230-5.
10.
Knapp P. The surgical treatment of double-elevator paralysis. Trans Am Ophthalmol Soc
1969;67:304-23. 11.
Kocak-Altintas AG, Kocakkkk-Midillioglu I, Dabil H, Duman S. Selective management of double elevator palsy by either inferior rectus recession and/or Knapp type transposition surgery. Binocul Vis Strabismus Q 2000;15:39-46.
12.
Struck MC, Larson JC. Surgery for supranuclear monocular elevation deficiency. Strabismus 2015;23:176-81.
13.
Luo WT, Qiao T, Ye HY, Li SH, Chen QL. Clinical features and surgical treatment of double elevator palsy in young children. Int J Ophthalmol 2018;11;1352-57.
14.
Li Y, Sun L, Zhang W, Zhao K. Comparison of augmented and nonaugmented modified Knapp procedure for the treatment of nonrestrictive double elevator palsies. J AAPOS 2016;20:401-4.
FIG 1. Pre- and postoperative vertical deviations to the patients. Patients 1-21 received fulltendon transposition surgery; patients 22-31, augmented tendon transposition surgery; and patients 32-39, partial tendon transposition surgery.
Table 1. Epidemiological and clinical features of patients with type 2 monocular elevation deficiency (N = 39) Study parameter Age, years Sex, no. Male Female Affected eye Right Left VD, PD Preoperative Postoperative Elevation, 0 to −4 Preoperative Postoperative AHP Yes No Ptosis Pseudoptosis b Stereopsis Yes No
Resulta 8.23 ± 7.32 (1-25) 18 (46.15) 21 (53.85) 21 (53.85) 18 (46.15) 22.73 ± 4.60 (14-30) 3.30 ± 2.80 (0-12) −2.82 ± 0.75 (−2 to −4) −0.94 ± 0.84 (0 to −2) 25 (64.1) 14 (35.9) 14 (35.9) 25 (64.1) 8 (27.6) 21 (72.4)
AHP, abnormal head posture; PD, prism diopter; VD, vertical deviation. a
Number (%) or mean ± standard deviation (range). Of the 39 patients, stereopsis could be evaluated in 29.
b
Table 2. Comparison of transposition techniques
Percent surgical success a VD, PD Preoperative Postoperative a Elevation limitation Preoperative Postoperative Post-op depression limitationa Corrected VD, PD
Full 71.4 (15/21)
90 (9/10)
Partial 62.5 (5/8)
Total 74.4 (39/29)
22.50 ± 4.17 (14-30) 3.50 ± 1.27 (0-12)
23.75 ± 4.78 (18-30) 1.75 ± 1.14 (0-8)
20.50 ± 3.98 (14-25) 4.12 ± 2.78 (0-10)
22.73 ± 4.60 (14-30) 3.30 ± 2.80 (0-12)
−2.80 ± 0.74 (−2 to −4) −0.80 ± 0.64 (0 to −2) −0.04 ± 0.21 (n = 1 [−1])b 19
−3.20 ± 0.78 (−2 to −4) −0.90 ± 0.73 (0 to −2) −0.40 ± 0.84 (n = 2 [−2, −2])b 22
−2.37 ± 0.51 (−2 to −4) −1.12 ± 0.99 (0 to −2) — 16.38
−2.82 ± 0.75 (−2 to −4) −0.94 ± 0.84 (0 to −2) −0.12 ± 0.46 (N = 39) 19.43
PD, prism diopter; VD, vertical deviation. a b
Mean ± standard deviation (range). Level of limitation in brackets.
Augmented
Table 3. Summary of different transposition techniques Study 5
Bagheri et al 6 Burke et al 7 Yurdakul et al 8 Snir et al Kamlesh9 10 Knapp 11 Kocak et al 13 Luo et al 14 Li et al Current study
No. cases 8 13 7 14 10 15 5 21 22 39
Average correction, prism diopters Full Augmented Partial 25 — — 21 — — 22 (n = 5) — 14 (n = 2) 9 (n = 6) 18 (n = 8) — — — 25 38 — — 20 — — 23 (n = 16) 34 (n = 5) — 28 (n = 15) 32 (n = 7) — 19 (n = 21) 22 (n = 10) 16 (n = 8)
S1091-8531(19)30583-X
DOI:
https://doi.org/10.1016/j.jaapos.2019.09.015
Reference:
YMPA 3116
To appear in:
Journal of AAPOS
Received Date: 26 December 2018 Revised Date:
8 September 2019
Accepted Date: 22 September 2019
Please cite this article as: Ocak OB, Inal A, Aygit ED, Celik S, Ocak SY, Gurez C, Pasaoglu IB, Gokyigit B, Comparison of different tendon transposition techniques for the treatment of monocular elevation deficiency type 2, Journal of AAPOS (2020), doi: https://doi.org/10.1016/j.jaapos.2019.09.015. This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Copyright © 2019, American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.
Comparison of different tendon transposition techniques for the treatment of monocular elevation deficiency type 2 Osman Bulut Ocak, MD,a Asli Inal, MD,a Ebru Demet Aygit, MD,a Selcen Celik, MD,a Serap Yurttaser Ocak, MD,b Ceren Gurez, MD,a Isil Basgil Pasaoglu, MD,a and Birsen Gokyigit, MD,a Author affiliations: aUniversity of Health Sciences, Beyoğlu Eye Research and Training Hospital, İstanbul, Turkey; bUniversity of Health Sciences, Okmeydani Research and Training Hospital, İstanbul, Turkey Submitted December 26, 2018. Revision accepted September 23, 20 Correspondence: Osman Bulut Ocak, Strabismus Department, Beyoğlu Eye Research and Training Hospital, Bereketzade Mahallesi, Bereketzade Cami Sk. 2/4, 34437, Beyoğlu/İstanbul (email: [email protected]). Word count: 1,945 Abstract only: 241
Abstract Purpose To compare results of three different tendon transposition techniques (Knapp procedure and two modified techniques) for the treatment of type 2 monocular elevation deficiency (MED) patients. Methods The medical records of patients with MED type 2 operated on at a single institution from 2000 to 2016 were reviewed retrospectively. Patients were divided into three vertical transposition groups: (1) full tendon width, (2) augmented surgery; and (3) partial tendon width. Surgical success was defined as no severe limitation of upgaze, hypotropia of <6∆, and no hypertropia in primary position. Pre- and postoperative vertical deviations in the primary position and limitations in elevation levels were compared. Results A total of 39 patients were included. The pre- and postoperative deviations in the full-tendon group were 22.50∆ ± 4.17∆ and 3.50∆ ± 1.27∆, respectively; in the augmented surgery group, 23.75∆ ± 4.78∆ and 1.75∆ ± 1.14∆; and in the partial-tendon group, 20.50∆ ± 3.98∆ and 4.12∆ ± 2.78∆. Corrected vertical deviations were 19∆, 23∆, and 16∆, respectively. The pre- and postoperative limitation of elevations were −2.80 and −0.80 in the full-tendon group, −3.20 and −0.90 in the augmented surgery group, and −2.37 and −1.12 in the partial-tendon group. The preand postoperative vertical deviation improvements and limitations of elevation were statistically significant (P < 0.05) in all groups. Success was achieved in 29 patients (74%). Conclusions In this study cohort, all three procedures were reasonably effective in improving vertical deviations and limitation of elevation.
Monocular elevation deficiency (MED) was initially identified as paralysis of the superior rectus and inferior oblique muscles, or double elevator palsy.1 Restriction of the inferior rectus muscle was found to play an important role in the etiology, and MED has been classified into three subgroups2,3: type 1 is a restrictive form that affects the inferior rectus muscle; type 2 is a paretic form that affects superior rectus muscle; and type 3 is a combined form that affects both muscles.3-5 The standard surgical procedure for MED type 2 patients is full tendon width transposition of the medial rectus and lateral rectus muscles (Knapp procedure).6,7 Recently, different tendon transposition techniques have been described and found to be effective for correcting vertical deviations and improvement of limitation of elevation.8,9 The aim of the present study was to compare the effects of different tendon transposition techniques on the vertical deviation and limitation of elevation in MED type 2 patients. Subjects and Methods This study was approved by the local the Taksim Research and Training Hospital, Clinical Researchs Ethical Board. Data handling and study protocols were compliant with the principles of the Declaration of Helsinki. The medical records of MED patients who underwent strabismus surgery at University of Health Sciences Beyoğlu Eye Research and Training Hospital between 2000 and 2016 were retrospectively reviewed. Patients with type 2 MED who underwent tendon transposition surgery for the correction of hypotropia were included. Exclusion criteria were previous strabismus surgery, different ocular and neurological pathologies, and follow-up of <12 months. Sex, age, affected eye, and medical and family histories were recorded. All patients underwent complete ophthalmic and orthoptic examinations before and after surgeries, including
cycloplegic refraction with cyclopentolate 1%. Binocularity was assessed using the Titmus Fly test for near vision and the Worth 4-Dot test for distance vision. Abnormal head posture and ptosis/pseudoptosis were noted. Pre- and postoperatively, the distance vertical deviations were measured using the prism base cover test, with the prism bars placed on the paretic eye at a primary position. All deviations were measured with appropriate spectacle correction. Limitations of elevation were graded on a scale of 0 to −4, both before and after surgeries, with 0 indicating no limitation and −4 indicating no movement. Surgical Techniques All surgeries were performed under general anesthesia by the same surgeon (BG) using a limbal incision. Forced duction and exaggerated traction tests were performed preoperatively. Standard full-tendon transposition was performed as described by Knapp.10 A full tendon width supraplacement of the horizontal rectus muscles in a position adjacent to the corners of the insertion of the superior rectus muscle was performed. Horizontal rectus muscles were aligned with the spiral of Tillaux. Augmented tendon transposition surgery was performed as described by Snir and colleauges.8 In this procedure, after full tendon width transposition, the posterior fixation suture was anchored to the sclera 8 mm posterior to the insertion of the superior rectus muscle near the nasal and temporal borders, thereby fixing 25% of the belly of the transposed medial rectus muscle and the lateral rectus muscle adjacent to the superior rectus muscle and aligned with the spiral of Tillaux. Partial tendon width transposition was performed as described by Kamlesh and colleagues.9 Transposition of equally divided (up to 15 mm) horizontal rectus muscles and the superior part of these muscles were transposed to the nearby insertion of the superior rectus
muscle aligned with the spiral of Tillaux. The full-tendon technique was used in all patients between 2000 and 2003. The surgical technique was decided according to vertical deviation measurements between 2003 to 2005. In 2003, full tendon width transposition was performed on patients with deviation of >25∆ and partial tendon width transposition was performed on patients with deviation of ≤25∆, following the recommendations of Kamlesh and colleagues.9 With publication of the augmented tendon transposition technique in 2005,8 the surgical technique was determined according to vertical deviations and limitations of elevation. In their study, vertical deviation of approximately 18∆ was corrected with surgery; the authors also found that limitation of elevation decreased more using augmented surgery than in did with unaugmented full tendon width transposistion.8 Accordingly, after 2005 full tendon with surgery was chosen for patients with deviation of 18∆ and limitation of elevation levels of −2; partial tendon width surgery, for patients with deviation of <18∆; and augmented transposition surgery, for all patients with deviation >25∆. Patients with −2 and −3 limitation of elevation and vertical deviations between 18∆ and 25∆ underwent augmented transposition surgery. Surgical success was defined as no severe limitation (−3 or −4), hypotropia of <6∆, and no hypertropia in primary position. Surgical complications were noted. Statistical analyses were performed with the e-PICOS program. Comparisons of pre- and postoperative values for each procedure were evaluated using the Wilcoxon test. P values of <0.05 were considered statistically significant. Results A total of 39 patients diagnosed with type 2 MED who underwent surgery met inclusion criteria. The epidemiology, clinical features, and pre- and postoperative vertical deviation means of all
patients are shown in Table 1. The mean hypotropia at distance before surgery was 22.73∆ ± 4.60∆ (range, 14∆-30∆); at final follow-up, 3.30∆ ± 2.80∆ (range, 0∆-10∆). The mean corrected vertical deviation was 19.43∆ ± 1.80∆ at distance. Pre- and postoperative vertical deviations of all patients are shown in Figure 1. We achieved surgical success in 29 cases (74%) after a single surgery. Postoperatively, the mean elevation deficit decreased from −2.82 ± 0.75 (range, −2 to −4) to −0.94 ± 0.84 (range, 0 to −2). Comparing pre- and postoperative values, all parameters were found to differ significantly (P < 0.05 [Wilcoxon test]). Surgical results are shown in Table 2. No postoperative complications (eg, anterior segment ischemia) were noted. Diplopia was not found because of absence of stereopsis, suppression, or amblyopia. No gain in stereopsis was noted. Anomalous head position improved but was not eliminated because of residual limitations of elevation and ptosis. The mean followup time was 26.14 ± 6.76 months (range, 20-40 months). The full-tendon technique was performed in 21 patients, with surgical success in 15 (71%). The mean vertical deviation in this group was 22.50∆ ± 4.17∆ (range, 14∆-30∆) preoperatively; 3.50∆ ± 1.27∆ (range, 0∆-12∆), postoperatively. Mean corrected vertical deviation was 19∆. The mean limitation of elevation was −2.80 ± 0.74 (range, −2 to −4) preoperative; −0.80 ± 0.64 (range, 0 to −2), postoperatively. See Table 2. Improvement in limitation in elevation and vertical deviation were significant (P < 0.05 [Wilcoxon test]). Six patients did not achieve surgical success; the mean vertical deviation in these patients was 26.12∆ ± 5.26∆. One patient had a reduction of limitation of downgaze to −1 after surgery, from no preoperative limitation. Ten patients were included in the augmented surgery group; all but 1 did not achieve
surgical success. The mean pre- and postoperative vertical deviations were 23.75∆ ± 4.78∆ and 1.75∆ ± 1.14∆, respectively. Mean correction was 22∆. Mean limitation of elevation was −3.20 ± 0.78 preoperatively and −0.90 ± 0.73 postoperatively (Table 2). All changes were statistically significant (P < 0.05 [Wilcoxon test]). One patient who failed had a deviation of 30∆ before surgery and 8∆ after. In 2 patients (20%) limitation of downgaze was reduced to −2 after surgery. Also, there was no hypertropia in primary position for these 2 patients. Eight patients were included the partial-tendon group, of whom 5 (63%) had surgical success. The mean vertical deviations were 20.50∆ ± 3.98∆ (range, 14∆-25∆) preoperatively and 4.12∆ ± 2.78∆ (range, 0∆-10∆) postoperatively. Mean corrected prism diopters was 16.38∆ (Table 2). Change in vertical deviation postoperatively were found significantly different. The change in limitation of elevation postoperatively was also significantly different (P < 0.05 [Wilcoxon test]); however, limitation of elevation levels were higher than in the other transposition techniques (−2.37 ± 0.51 to −1.12 ± 0.99) after surgery. In 4 patients (50%) limitation of elevation was −2 after surgery. No patient complained about limitation of elevation. No limitation of downgaze was been noted. Discussion In our study cohort, superior rectus paralysis without inferior rectus restriction was the main etiopathology of MED type 2 (supranuclear paralysis),3 which is typically treated using the Knapp procedure.6,7 This procedure corrects hypotropia and improves limitation of elevation7,11; however, results are unpredictable.6,12 We evaluated the efficacy of the standard Knapp procedure, augmented transposition surgery, and partial-tendon surgery for hypotropia and limitation of elevation in patients with MED type 2. Analysis of the published results of full-tendon transposition are shown in Table 3. In the
literature, the average vertical correction is variable, ranging from 9∆ to 40∆. In the current study, the average corrected vertical deviation was 19∆ using this technique. Improvement in limitation of elevation was also variable. Luo and colleagues13 found a 1.69 ± 0.87 improvement in elevation. Li and colleagues14 reported that the corrected vertical deviation was 28∆, and improvement in elevation was 1.90 ± 0.60. We found an improvement of 2.00 ± 0.10 in elevation. Snir and colleagues8 found that augmented tendon transposition was more effective than the full-tendon technique in correcting vertical deviation and limitation of elevation. Luo and colleagues13 reported a vertical deviation correction of 34∆ and improvement of 1.80 ± 0.45 in limitation of elevation. Li and colleagues14 found limitations of downgaze in all of their 8 patients but did not observe diplopia in the reading position. In the current study, we found an improvement of 2.30 ± 0.05 in elevation in 2 of 10 patients who had −2 limitation of downgaze, but because of deep amblyopia and loss of binocularity, no diplopia on downgaze occurred. Partial-tendon surgery also allowed for correction of horizontal strabismus in the paretic eye during same session.9 Kamlesh and Dadeya9 reported vertical and horizontal corrections of 25∆ and 20∆, respectively in vertical and horizontal corrections and horizontal corrections and significant improvement in elevation. We found a 16.38∆ correction in vertical deviations and 1.24 ± 0.48 improvement in elevation. We did not perform simultaneous horizontal strabismus surgery in our patients. The major limitation of this study is its retrospective design. A study strength is that the relatively long study period of more than 16 years. Because of the retrospective design of the study, surgical selections were variable by years, and we could not homogenize and randomize the group characteristics.
References 1.
White JW. Paralysis of the superior rectus muscle. Trans Am Ophthalmol Soc 1933;31:551-84.
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Scott WE, Jackson OB. Double elevator palsy: the significance of inferior rectus restriction. Am Orthopt J 1977;27:5-10.
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Raab EL, Abay AA, Bloom JN, Edmond JC, Lueder GT. Pediatric Ophthalmology and Strabismus. San Francisco, CA; American Academy of Ophthalmology; 2010:128-29.
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Ocak OB, Inal A, Aygit ED, et al. Surgical management in type 1 monocular elevation deficiency. J Pediatr Ophthalmol Strabismus 2018;55:369-74.
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Bagheri A, Sahebghalam R, Abrishami M. Double elevator palsy, subtypes and outcomes of surgery. J Ophthalmic Vis Res 2008;3:108-13.
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Burke JP, Ruben JB, Scott WE. Vertical transposition of the horizontal recti (Knapp procedure) for the treatment of double elevator palsy: effectiveness and long-term stability. Br J Ophthalmol 1992;76:734-7.
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Yurdakul NS, Ugurlu S, Maden A. Surgical treatment in patients with double elevator palsy. Eur J Ophthalmol 2009;19:697-701.
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Snir M, Friling R, Kalish-Stiebel H, Bourla D, Weinberger D, Axer-Siegel R. Combined rectus muscle transposition with posterior fixation sutures for the treatment of doubleelevator palsy. Ophthalmology 2005;112:933-8.
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Kamlesh DS. Surgical management of unilateral elevator deficiency associated with horizontal deviation using a modified Knapp’s procedure. Ophthalmic Surg Lasers Imaging 2003;34:230-5.
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Knapp P. The surgical treatment of double-elevator paralysis. Trans Am Ophthalmol Soc
1969;67:304-23. 11.
Kocak-Altintas AG, Kocakkkk-Midillioglu I, Dabil H, Duman S. Selective management of double elevator palsy by either inferior rectus recession and/or Knapp type transposition surgery. Binocul Vis Strabismus Q 2000;15:39-46.
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Struck MC, Larson JC. Surgery for supranuclear monocular elevation deficiency. Strabismus 2015;23:176-81.
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Luo WT, Qiao T, Ye HY, Li SH, Chen QL. Clinical features and surgical treatment of double elevator palsy in young children. Int J Ophthalmol 2018;11;1352-57.
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Li Y, Sun L, Zhang W, Zhao K. Comparison of augmented and nonaugmented modified Knapp procedure for the treatment of nonrestrictive double elevator palsies. J AAPOS 2016;20:401-4.
FIG 1. Pre- and postoperative vertical deviations to the patients. Patients 1-21 received fulltendon transposition surgery; patients 22-31, augmented tendon transposition surgery; and patients 32-39, partial tendon transposition surgery.
Table 1. Epidemiological and clinical features of patients with type 2 monocular elevation deficiency (N = 39) Study parameter Age, years Sex, no. Male Female Affected eye Right Left VD, PD Preoperative Postoperative Elevation, 0 to −4 Preoperative Postoperative AHP Yes No Ptosis Pseudoptosis b Stereopsis Yes No
Resulta 8.23 ± 7.32 (1-25) 18 (46.15) 21 (53.85) 21 (53.85) 18 (46.15) 22.73 ± 4.60 (14-30) 3.30 ± 2.80 (0-12) −2.82 ± 0.75 (−2 to −4) −0.94 ± 0.84 (0 to −2) 25 (64.1) 14 (35.9) 14 (35.9) 25 (64.1) 8 (27.6) 21 (72.4)
AHP, abnormal head posture; PD, prism diopter; VD, vertical deviation. a
Number (%) or mean ± standard deviation (range). Of the 39 patients, stereopsis could be evaluated in 29.
b
Table 2. Comparison of transposition techniques
Percent surgical success a VD, PD Preoperative Postoperative a Elevation limitation Preoperative Postoperative Post-op depression limitationa Corrected VD, PD
Full 71.4 (15/21)
90 (9/10)
Partial 62.5 (5/8)
Total 74.4 (39/29)
22.50 ± 4.17 (14-30) 3.50 ± 1.27 (0-12)
23.75 ± 4.78 (18-30) 1.75 ± 1.14 (0-8)
20.50 ± 3.98 (14-25) 4.12 ± 2.78 (0-10)
22.73 ± 4.60 (14-30) 3.30 ± 2.80 (0-12)
−2.80 ± 0.74 (−2 to −4) −0.80 ± 0.64 (0 to −2) −0.04 ± 0.21 (n = 1 [−1])b 19
−3.20 ± 0.78 (−2 to −4) −0.90 ± 0.73 (0 to −2) −0.40 ± 0.84 (n = 2 [−2, −2])b 22
−2.37 ± 0.51 (−2 to −4) −1.12 ± 0.99 (0 to −2) — 16.38
−2.82 ± 0.75 (−2 to −4) −0.94 ± 0.84 (0 to −2) −0.12 ± 0.46 (N = 39) 19.43
PD, prism diopter; VD, vertical deviation. a b
Mean ± standard deviation (range). Level of limitation in brackets.
Augmented
Table 3. Summary of different transposition techniques Study 5
Bagheri et al 6 Burke et al 7 Yurdakul et al 8 Snir et al Kamlesh9 10 Knapp 11 Kocak et al 13 Luo et al 14 Li et al Current study
No. cases 8 13 7 14 10 15 5 21 22 39
Average correction, prism diopters Full Augmented Partial 25 — — 21 — — 22 (n = 5) — 14 (n = 2) 9 (n = 6) 18 (n = 8) — — — 25 38 — — 20 — — 23 (n = 16) 34 (n = 5) — 28 (n = 15) 32 (n = 7) — 19 (n = 21) 22 (n = 10) 16 (n = 8)