STRABO care less traumatic strabismus surgery technique in the rehabilitation of patients with strabismus

Purpose. Comparative evaluation of patients' rehabilitation using less traumatic STRABO care technique and traditional methods of strabismus surgery. Material and methods. Sixty-two patients with esotropia were included in the study. All participants underwent medial rectus muscle recession and lateral rectus muscle plication. Patients were divided into two groups. In the main group (38 patients), the surgery was performed with less traumatic technique. Radio-wave knife was used for dissecting the connective tissues. Vicryl 7-0 was used as suture material. Traditional surgical technique was used in control group (24 patients). Scissors were used as a cutting tool and Vicryl 6-0 as a suture material. In the postoperative period conjunctival hyperemia, and width of the palpebral fissure were assessed after the surgery. Conjunctival flap edema (thickness) was measured one day after surgery by the anterior segment optical coherence tomography (AS-OCT). Results. The 1st day after surgery the median thickness of the conjunctival flap above the recession site according to AS-OCT was on average 1.5 times thinner in the main group than in the control group: 405 (351–555) µm vs. 618 (513–732) µm; p<0.001. During the entire observation period in the eyes operated with less traumatic technique, hyperemia was less expressed and palpebral fissure was wider as compared to the control group, where the standard surgical technique was used. Conclusion. Less traumatic STRABO care surgical technique allows to reduce the inflammatory response of tissues in response to surgical intervention and to facilitate the course of the early postoperative period. Key words: strabismus surgery, low-traumatic technique, radio-wave knife, oculomotor muscles, rehabilitation, STRABO care, anterior segment optical coherence tomography

Outcomes of half-width vertical rectus transposition augmented with posterior fixation sutures for sixth cranial nerve palsy

AIM: To describe the experience with half-width vertical muscles transposition (VRT) augmented with posterior fixation sutures. METHODS: The clinical charts of all patients, who underwent half-width VRT augmented with posterior fixation sutures for sixth cranial nerve palsy from January 2003 to December 2018, were retrospectively reviewed. For each patient, pre- and post-operatively, the largest measured angle was used for the calculations, usually resulting with the angle for distance, except in young infants, where measurements were made at near fixation using the Krimsky test. RESULTS: Fifteen patients met the inclusion criteria for the study, of them 9 (60.0%) had also medial rectus muscle recession at the time of surgery. Mean follow-up period was 21.4±23.2mo (range 1.5-82mo). Preoperative mean esotropia was 51.3±19.7 prism diopter (PD; range 20-90 PD). Postoperative mean deviation on final follow-up was 7.7±20.2 PD (range -40 to 35 PD; P=0.018). In all patients with preoperative abnormal head position, improvement was noted. Ten (66.7%) patients had improvement in abduction and 10 (66.7%) patients reported improvement in their diplopia, by final follow-up. The addition of medial rectus recession was correlated with a larger change in postoperative horizontal deviation compared to baseline (P=0.026). Two (13.3%) patients developed a vertical deviation in the immediate postoperative period which had resolved in one of them. CONCLUSION: Half-width VRT augmented with posterior fixation suture, with or without medial rectus muscle recession, is an effective and safe procedure for esotropia associated with sixth cranial nerve palsy. A major improvement in the angle of deviation is expected. Most patients will have improvement in their abnormal head position and diplopia.

Outcomes of Early Surgery in Children under Four Years Old with Large Angle Intermittent Exotropia

Purpose: To find out the significance of early surgery in children of 4 years old and under with large angle intermittent exotropia of 35 prism diopters (PD) and more by examining the results of bilateral lateral rectus recession surgery and factors influencing the surgical outcome.Methods: It was a retrospective study of patients who underwent bilateral lateral rectus muscle recession surgery between 2006 to 2016 with intermittent exotropia greater than or equal to 35 PD and who were able to follow-up for at least 2 years after surgery were divided into two groups based on age of 4 years old. The surgical motor success was defined as exodeviation less than 10 PD, esodeviation less than 8 PD. The angle of deviation, binocular function, best corrected visual acuity, and amount of corrected PD per lateral recession (PD/mm) were compared at each observation point after surgery.Results: The motor success of bilateral rectus muscle recession surgery was 85% in children of age 4 years and under, 65.5% in age over 4 years. Success rate of early surgery was 1.3 times higher in younger age group, but there was no statistical meaning. The complication of surgery after 2 years of follow up was less in younger group-the rate of recurrent exotropia was 15% in younger group, 31.3% in older group and the rate of consecutive esotropia was 0% and 3.1%, respectively. Stereoacuity after 2 years of surgery was not fall behind in younger group compared to older group.Conclusions: It is possible to obtain good surgical results by performing early surgery rather than hesitating to operate due to the younger age in patients younger than 4 years old with large angle exotropia of 35 PD and more for long-term follow up and efficient patient management.

New Modification of Vertical Muscle Transposition to Enhance Abducting Force in Sixth Nerve Palsy

Purpose:Since 1907, multiple transposition procedures have been established for the treatment of abducens paralysis. In this study, we try to determine where the transposed muscle should be reattached in order to increase the tangential force necessary to improve abduction.Methods:Retrospective case review of 12 consecutive patients with abducens paralysis. All patients underwent the transposition procedure between 2016 and 2019.Vertical rectus muscles are transposed to the insertion of lateral rectus muscle: The temporal parts are joined and sutured to the sclera on top of the lateral rectus muscle in the middle of the insertion. The nasal parts are sutured to the sclera following the spiral of Tillaux. The muscle junction suture is placed 8 mm from the insertion: The temporal parts of the vertical muscles bellies are joined and sutured to the lateral rectus muscle. A full tendon transposition was performed on 11 patients, a half tendon transposition procedure on one patient. The minimum follow-up was 3 months.Results:The mean preoperative deviation was ET of 37° (range: ET 24° to ET 51°). The mean preoperative abduction limitation was 5 mm from midline (range: -7 to -1mm). The postoperative mean deviation was ET of 2° PD (range: 0 to ET 5°). The postoperative mean abduction improvement was 5mm past midline (range: +2 to +6mm). There were no complications, or signs of anterior segment ischemia. Conclusions:To achieve the maximal abductive force from the transposed muscles, we suggest that the vertical muscles be reattached as close as possible to the middle of the lateral rectus insertion.

Worldwide outcomes of nasal transposition of the split lateral rectus muscle for strabismus associated with 3rd-nerve palsy

Background/aimsTo determine success rate and complications associated with nasal transposition of the split lateral rectus muscle (NTSLR) for treating strabismus from 3rd-nerve palsy.MethodsAn international, multicentre, registry of patients with unilateral 3rd-nerve palsy treated with NTSLR was created. Patients with concurrent surgery on the contralateral eye were excluded. Primary outcome was horizontal alignment within 15 prism dioptres (PD) of orthotropia. Incidence of technical difficulties and vision-threatening complications by 6 months post-procedure were reported.ResultsNinety-eight patients met inclusion criteria. Median age was 33.5 years (IQR 10.75–46). Aetiologies included congenital (31%), neoplastic (16%) and traumatic (15%). Twenty-five per cent of patients had prior ipsilateral strabismus surgery. Median exotropia decreased from 70PD preoperatively (IQR 50–90) to 1PD postoperatively (IQR 0–15.5), with a success rate of 69%. Performing concurrent superior oblique muscle tenotomy (SOT) was independently associated with success (p=0.001). Technical challenges occurred in 30% of cases, independently associated with a history of ipsilateral strabismus surgery (p=0.01). Eleven per cent of patients had vision-threatening complications, independently associated with more posterior placement of the split lateral rectus (LR) muscle (p<0.001), and most commonly transient serous choroidal effusion. Surgical placement of the split LR muscle within 4.25 mm of the medial rectus (MR) muscle insertion reduced this risk.ConclusionNTSLR significantly improved primary position alignment altered by 3rd-nerve palsy. Concurrent SOT and placement of the split LR muscle ≤4.25 mm posterior to the MR muscle insertion optimised outcomes. NTSLR proved technically challenging when prior ipsilateral strabismus surgery had been performed.

Clinical characteristics and surgical outcomes of isolated inferior rectus palsy

Aim As isolated inferior rectus muscle (IRM) palsy represents a rare clinical entity, very limited information is available on this condition. The aim of this report was to elucidate the etiology, clinical characteristics and surgical outcomes of isolated IRM palsy. Methods Isolated IRM palsy cases who underwent surgical treatments at the Zhongshan Ophthalmic Center, Sun Yat-sen University, China over the period from January 2008 to June 2019 were reviewed retrospectively. Data evaluated from these cases included their etiology, ocular alignment, ocular motility, surgical procedures and surgical outcomes. Results A total of 61 patients (40 males, 21 females) were included in this review. Their mean ± SD age was 27.21 ± 16.03 years (range: 2 to 73 years). In these cases, 32 (52.5%) involved traumatic injury, 28 (45.9%) congenital hypoplasia or absence of inferior rectus and 1 (1.6%) with thyroid ophthalmopathy. The right eye was affected in 33 patients (54.1%), the left in 24 patients (39.3%), and both eyes in 4 patients (6.6%). The main clinical presentations consisted of hypertropia of the affected eye, motility limitation in abduction and depression and incyclotropia. After treatment consisting of various surgical approaches, including muscle repair or resection of the affected inferior rectus, recession of ipsilateral superior rectus, elongation of contralateral superior oblique and partial transposition of the horizontal rectus, the isolated IRM palsy was rectified in 49 patients (80.4%) with one surgery, while 11 cases (18.0%) required two surgeries and 1 case (1.6%) needed three surgeries. Finally, 52 patients (85.2%) showed a complete recovery, 6 (9.9%) improved and 3 (4.9%) experienced a surgical failure. Conclusion The main etiologies of isolated IRM palsy involved traumatic injury and developmental events. Overall, surgical outcomes of the various approaches employed were quite effective.

Morphological change of the posterior pole following the horizontal strabismus surgery with swept source optical coherence tomography

Extraocular muscle movement during strabismus surgery causes changes in eyeball shape. Because extraocular muscle insertion is in front of the equator, it is thought that changes due to strabismus surgery mainly occur in the anterior segment. However, changes in the posterior segment of eye may also occur, which may also result in changes in refractive error after strabismus surgery. Using a 3-dimensional reconstruction technique (en face imaging) of the swept source optical coherence tomography, we determined and quantitatively measured the posterior polar change. The deepest interface between Bruch’s membrane and the choroid could be identified as the deepest point of the eyeball (DPE), and the location of the DPE relative to the optic disc and the fovea was measured. After lateral rectus muscle recession, the DPE moved away from the fovea, but after medial rectus muscle recession, the DPE moved toward the fovea. The amount of DPE movement differed by age and preoperative refractive error. Our findings suggest that the positional shift of the rectus muscle in horizontal strabismus surgery causes a structural change in the posterior segment of the eye, and the postoperative refractive changes may be related to this shift.

Polyester 5-0 Suture for Porous Implant Placement After Retinoblastoma Enucleation: Analysis of 120 Sockets

Background: Techniques used to suture the rectus muscle to the implant can influence the implant-related complications which is still a major problem following retinoblastoma enucleation. The goals of this work were to report the efficacy among patients with retinoblastoma who underwent enucleation followed by porous implant placement with the rectus muscles sutured with 5-0 polyester suture.Methods: This was a retrospective study of consecutive patients with retinoblastoma who underwent primary enucleation and porous implant placement with the rectus muscles tagged and sutured to the implant with polyester 5-0 suture. All the patients were followed up for a minimum of 2 years. The main outcome measure was implant exposure. The secondary efficacy measures were other implant-related complications.Results: A total of 120 patients (120 eyes) underwent primary enucleation and porous implant placement were included. Postoperatively, 10/120 (8.3%) eyes developed exposure and conjunctival granuloma. Exposure was the most common postoperative complication (7/10, 70.0%). There were no cases of implant extrusion, migration, or infection.Conclusions:Polyester 5-0 sutures are successful in patients with retinoblastoma who underwent enucleation followed by porous implant placement. Complications are minimal. Polyester 5-0 sutures were not associated with unacceptable complications in this pediatric population.