Comparison between bupivacaine injection and mini-tenotomy in the management of horizontal small angle strabismus in children.

PURPOSE: To compare the outcome of bupivacaine (BUP) injection vs mini-tenotomy of extra-ocular muscles in treating small angle horizontal strabismus in children. METHODS: A prospective comparative study that included a total of 40 patients. Twenty patients received 3 ml of 0.75% Bupivacaine (BUP) injection in both medial recti in case of exotropia and in both lateral recti in case of esotropia. MRI orbit was performed before and 30-60 days' post injection of bupivacaine to estimate changes in muscle size. Mini-tenotomy was done in the other 20 patients, performed on both lateral recti in case of exotropia and on both medial recti in case of esotropia. RESULTS: Mean change of alignment at the end of 6 months in exotropic patients in bupivacaine group was 5.50 ± 4.10 PD and in esotropia patients 4.00 ± 3.38 PD with an average increase in muscle thickness of 0.12 mm ± 0.08 and 0.13 mm ± 0.09 in exotropia and esotropia, respectively. There was an average increase in volume 23 mm3 ± 17.3 and 17.00 mm3 ± 9.50 in exotropia and esotropia, respectively, as measured with MRI. The mean change of alignment in mini-tenotomy was 5.33 ± 4.12 PD, 5.75 ± 4.95 PD in exotropia and esotropia, respectively. CONCLUSION: Bupivacaine and mini-tenotomy are safe and effective alternative treatment, that improved eye alignment in 65% of patients with small angle horizontal deviation.

Botulinum Toxin Injection in Horizontal Rectus Muscles Without Electromyography Using an Open Sky Versus a Closed Sky Technique.

PURPOSE: To ascertain whether electromyographic control when injecting botulinum toxin in the horizontal rectus muscles is necessary, and to compare the open sky and closed sky injection techniques that are used without electromyographic control. METHODS: The records of 135 patients with horizontal strabismus who received botulinum toxin injections were reviewed retrospectively. Sevoflurane or propofol anesthesia was used in children, and topical benoxinate hydrochloride was used in adults. Patients received a bilateral injection of 2.5 to 15 IU of botulinum toxin, without electromyographic control, into the medial or lateral rectus muscles to correct esotropia or exotropia, respectively. An open sky technique was used in 31 patients, and a closed sky technique was used in 104 patients. Postoperative alignment within 10 prism diopters (PD) of orthotropia was considered a successful outcome. RESULTS: A successful outcome at 6 months of follow-up was achieved in 47% of all patients: 59% of patients in the open sky group and 44% of patients in the closed sky group (P = .151). Botulinum toxin injection corrected a mean of 14 ± 9.705 PD in patients in the open sky group and 31 ± 20.589 PD in patients in the closed sky group to obtain mean residual angles of 21 ± 16.692 and 13 ± 11.901 PD, respectively. CONCLUSIONS: The results obtained without electromyographic assistance were not remarkably different from the studies using electromyographic control. Moreover, because the results of the open sky technique were not significantly superior to the closed sky technique, the latter was favored to shorten the operative time and postoperative convalescence, and to reduce the risk of postoperative adhesions and scarring, which made re-operations difficult. [J Pediatr Ophthalmol Strabismus. 2022;59(6):388-395.].

Predictive Value of Intraocular Lens Power Calculation Formulae in Children.

PURPOSE: To compare the accuracy of IOL power calculation formulae in a large cohort of children who underwent IOL implantation. SETTING: Cairo University Children Hospital. DESIGN: Retrospective, case series. METHODS: A retrospective chart review of all children <14 years, who underwent primary or secondary IOL implantation in Cairo University Children Hospital from January 2016 to December 2019, was performed. Absolute prediction error (APE) was calculated for SRKII, SRK/T, Holladay I and Hoffer-Q formulae using the patients' AL, keratometric (K) readings, implanted IOL power and refraction done two months postoperatively. RESULTS: The study included 308 eyes of 255 patients with a mean age of 4.74 ± 3.19 years at the time of surgery. The mean K-reading was 43.42 ± 3.57 diopters (D) and mean AL was 22.01 ± 1.93 mm. The percentage of eyes with APE within 0.5D was 27.7% (85 eyes), 32.2% (99 eyes), 30.6% (94 eyes) and 25.4% (78 eyes) with SRK II, SRK/T, Holladay I and Hoffer-Q formulae, respectively. APE was significantly lower with the SRK/T formula (P≤0.004) and significantly higher with the Hoffer-Q formula (P≤ 0.002). There was a negative correlation between the age of the patient and the APE of the SRK II formula (P=0.02). Moreover, the SRK/T, Holladay and Hoffer-Q formulae APEs were affected by the average k-readings (P=0.019, 0.005 and 0.035) respectively. CONCLUSION: The SRK/T and Holladay I formulae were the most predictable formulae in IOL power calculation in pediatric eyes.

Superior Rectus Transposition With Medial Rectus Recession Versus Medial Rectus Recession in Esotropic Duane Retraction Syndrome.

PURPOSE: To compare the results of augmented superior rectus transposition (with or without medial rectus recession) with simple medial rectus recession in the treatment of patients with esotropic Duane retraction syndrome. METHODS: This was a prospective, randomized, and interventional comparative study of 20 patients with esotropic type 1 Duane retraction syndrome. Patients were randomly divided into two groups. In the first group (superior rectus transposition group), superior rectus transposition with or without medial rectus recession was performed. In the second group (non-superior rectus transposition group), unilateral medial rectus recession was performed. RESULTS: Each group included 10 patients. Esotropia improved from 20.4 prism diopters (PD) preoperatively to 0.6 PD postoperatively in the superior rectus transposition group and from 22.5 PD preoperatively to 0.9 PD postoperatively in the non-superior rectus transposition group. Face turn improved from 11.5° preoperatively to 0.5° postoperatively in the superior rectus transposition group and from 12° preoperatively to 1.5° postoperatively in the non-superior rectus transposition group. Abduction improved in the superior rectus transposition group from -3.9 preoperatively to -3.1 postoperatively and from -3.9 preoperatively to -3.6 postoperatively in the non-superior rectus transposition group. Vertical deviation developed in two cases in the superior rectus transposition group. CONCLUSIONS: Both superior rectus transposition and medial rectus recession are effective in the elimination of esotropia and face turn in patients with esotropic Duane retraction syndrome. Superior rectus transposition is more effective in improving abduction, but it can be complicated by vertical deviation. [J Pediatr Ophthalmol Strabismus. 2020;57(5):309-318.].

Progression of High Anisometropia in Children.

PURPOSE: To investigate the onset and rate of progression of high anisometropia in myopic children younger than 13 years. METHODS: A retrospective study was performed on children with anisometropia younger than 13 years with myopia of more than 4.00 diopters (D) in the more ametropic eye and a difference in spherical equivalent refraction of 4.00 D between both eyes. All children had a complete ophthalmologic examination, including measurement of visual acuity and cycloplegic refraction every 3 to 6 months for at least 5 years. Change in the spherical equivalent and the cylindrical error for both eyes and changes in the difference in spherical equivalent refraction between both eyes were calculated for each patient at each visit. Linear, polynomial, logarithmic, and exponential fitting models were tested for both eyes and for the anisometropic difference between both eyes. The regression line with the greatest R2 value was considered best fit. RESULTS: Sixty-three patients fulfilled the inclusion criteria. The more ametropic eye grew in a regular fashion during the first 2 years of life, followed by a rapid decrease in the rate of growth to become almost stable after 4 years of age. The increase in myopia best fit a third-degree polynomial (cubic) model (R2 = 0.98). The less ametropic eye showed only a small increase in myopia during the follow-up period. The anisometropic difference between both eyes increased gradually during the first 2 years, then remained stable. CONCLUSIONS: High anisometropic myopia progresses rapidly in the first few years of life before becoming stable. [J Pediatr Ophthalmol Strabismus. 2017;54(5):282-286.].

Retinal ganglion cell complex changes using spectral domain optical coherence tomography in diabetic patients without retinopathy.

AIM: To assess the ganglion cell complex (GCC) thickness in diabetic eyes without retinopathy. METHODS: Two groups included 45 diabetic eyes without retinopathy and 21 non diabetic eyes. All subjects underwent full medical and ophthalmological history, full ophthalmological examination, measuring GCC thickness and central foveal thickness (CFT) using the RTVue® spectral domain-optical coherence tomography (SD-OCT), and HbA1C level. RESULTS: GCC focal loss volume (FLV%) was significantly more in diabetic eyes (22.2% below normal) than normal eyes (P=0.024). No statistically significant difference was found between the diabetic group and the control group regarding GCC global loss volume (GLV%) (P=0.160). CFT was positively correlated to the average, superior and inferior GCC (P=0.001, 0.000 and 0.001 respectively) and negatively correlated to GLV% and FLV% (P=0.002 and 0.031 respectively) in diabetic eyes. C/D ratio in diabetic eyes was negatively correlated to average, superior and inferior GCC (P=0.015, 0.007 and 0.017 respectively). The FLV% was negatively correlated to the refraction and level of HbA1c (P=0.019 and 0.013 respectively) and positively correlated to the best corrected visual acuity (BCVA) in logMAR in diabetic group (P=0.004). CONCLUSION: Significant GCC thinning in diabetes predates retinal vasculopathy, which is mainly focal rather than diffuse. It has no preference to either the superior or inferior halves of the macula. Increase of myopic error is significantly accompanied with increased focal GCC loss. GCC loss is accompanied with increased C/D ratio in diabetic eyes.

Changes in the axis of astigmatism and in fundus torsion following inferior oblique muscle weakening.

PURPOSE: To study the changes in fundus torsion and in the axis of astigmatism following inferior oblique (IO) myectomy in patients with inferior oblique overaction (IOOA). METHODS: The degree of fundus torsion and corneal astigmatism were prospectively evaluated before and 3 months after IO myectomy in patients with IOOA grade +2 or more in one or both eyes and an astigmatic error of ≥1 D. Fundus torsion was evaluated by measuring the disk foveal angle (DFA) using fundus photography. The axis of astigmatism was identified from the anterior sagittal map using Pentacam corneal imaging. RESULTS: A total of 54 eyes of 27 patients were included. Patients were divided into two groups: those with esotropia and those with exotropia. All patients had a preoperative DFA >8°, which decreased postoperatively in both groups (P < 0.01). Postoperatively, there was incyclorotation of the axis of astigmatism by >5° in 80% of the esotropic group and 75% of the exotropic groups (P < 0.01). CONCLUSIONS: Incyclorotation of the axis of astigmatism occurs after IO myectomy. Measurement of the change in the axis of astigmatism can be used to assess the torsional changes after IO myectomy in patients with IOOA.

Severe fibrosis of extraocular muscles after the use of lyophilized amniotic membrane in strabismus surgery.

Various techniques have been used to reduce adhesions after strabismus surgery. Wrapping the extraocular muscles with cryopreserved amniotic membrane has been reported to yield good results. In the case reported here, we used lyophilized amniotic membrane to wrap the extraocular muscles. Extensive adhesions developed, and inelastic, fibrotic muscles were discovered at a subsequent operation.