Treatment Of Strabismus Research Articles

A NEW APPROACH TO THE DOSING DEGREE OF ANTERIOR TRANSPOSITION OF THE INFERIOR OBLIQUE MUSCLE SURGERY FOR VERTICAL STRABISMUS

Introduction. Strabismus is the deviation of one eye from a common fixation point, associated with impaired of binocular vision. The eye’s position in horizontal and vertical directions looking straight determines the t ype of strabismus. Despite numerous reports of surgical interventions on the vertical action muscles, there is no a differentiated approach to the treatment of patients with this pathology. The search for the optimal methods and principles of surgical treatment of vertical strabismus caused by hyperfunction of the inferior oblique muscle, testifies to the relevance of developing new approaches to eliminate hypertropia depending on its severit y. The purpose — to develop a method of dosing the degree of anterior transposition of the inferior oblique muscle in the surgical treatment of vertical strabismus caused by hyperfunction of the inferior oblique muscle depending on severit y, and to evaluate its clinical efficacy. Patients And Methods. In the period from January 2013 to October 2015 60 children (96 eyes) aged from 3 to 17 years with a vertical strabismus caused by hyperfunction of the inferior oblique muscle were followed-up. All patients underwent a complete pre — and postoperative examinations. All patients received surgical treatment — weakening of the inferior oblique muscle through its anterior dosed transposition. Results. There were no intraoperative complications and specific complications t ypical for weakening surgeries on the inferior oblique muscle. Overcorrection wasn’t registered neither in the case of surgical treatment of large vertical angles of strabismus, no small vertical deviations. Restriction of mobilit y of the eyeballs wasn’t recorded throughout the observation period in any patient. Residual hyperfunction of the inferior oblique muscle was in 3 patients (5%). It did not exceed the value of the vertical, with the fusion and did not require additional surgical treatment. Conclusion. The technology will significantly improve the efficiency and safet y of treatment, reduce the risk of complications and the duration of surgery and anesthesia, the number of surgical treatment stages, to create optimal conditions for the rehabilitation of visual functions in children.

American Insight Into Strabismus Surgery Before 1838.

English surgeon John Taylor attempted to perform strabismus surgery in the 18th century. The field languished until, in Germany, treatment of strabismus by cutting an extraocular muscle was proposed by Louis Stromeyer in 1838 and performed by Johann Friedrich Dieffenbach in 1839. According to traditional teaching, there has never been any proof that anyone in the United States thought of the idea of strabismus surgery before Stromeyer’s report. In 1841, American surgeon William Gibson wrote that he had cut extraocular muscles to treat strabismus several times beginning in 1818 but never published his cases. Gibson’s former trainee Alexander E Hosack of New York confirmed Gibson’s memory. Interestingly, Hosack’s family had a connection with the family of New York oculist John Scudder Jr (1807-1843), whose reported cure of strabismus by cutting some of the fibers of an extraocular muscle was described in newspapers throughout the United States in 1837. Thus, Scudder’s report preceded that of Stromeyer. Scudder’s claim cannot be verified, but his description could have influenced Stromeyer, and demonstrates that the idea of strabismus surgery did exist in America before 1838.

Outcome of strabismus surgery by nonadjustable suture among adults attending a university hospital of Saudi Arabia.

To describe the outcome and safety of surgical treatment of Saudi adult patients with strabismus by nonadjustable suture and to evaluate the prevalence of diplopia and binocularity after strabismus correction. Retrospective analysis of medical records of 96 patients above the age of 16-years old with strabismus seen at the King Fahd Hospital of the King Faisal University (KFUH) from July 1st, 2000 to June 30th, 2007 who were underwent strabismus correction surgery. The demographic variables: pre- and post-operative alignment, binocularity, and visual acuity were analyzed. A total of 96 patients of whom 63 (66%) patients were male and 33 (34%) patients were female, aged 16 years and above underwent strabismus correction, 83 (86%) patients ended with postoperative orthophoria, 13 (14%) patients ended with postoperative residual deviation, 83 patients (86%) had defective vision with amblyopia. Improvement of binocularity and binocular visual acuity postoperatively was achieved in 32(33%). Forty (42%) of our patients developed transient diplopia postoperatively which disappeared within 6 weeks while only three developed permanent diplopia. The main cause of adult strabismus was childhood squint in 83 (86%) patients and traumatic in 3 (13%). Surgical treatment of strabismus in Saudi adult with nonadjustable suture is safe and effective procedure with low risk of complication and the incidence of diplopia is rare with better binocularity and binocular visual acuity.

The Shape of the Sky: The Art of Using Egocentric Stereopsis in the Treatment of Strabismus

A protocol for using stereopsis in the treatment of strabismus is described. Suitable for patients with either normal retinal correspondence (NRC) or anomalous binocular correspondence (ABC), the approach emphasizes the interactions between peripheral/egocentric and central/relative stereopsis in such dichoptic instrumentation as vectograms, digital instrumentation, and 3D movies. The paper then discusses the transfer of appreciation of stereopsis from such artificial dichoptic stereoscopic presentations to consciousness of egocentric and relative stereopsis in natural seeing, emphasizing the art, rather than the science, of treatment.

Outcomes of adjustable strabismus surgery in an Irish University Hospital.

Strabismus surgery aims to improve binocular vision, reduce diplopia, and enhance cosmesis. Adjustable strabismus procedures have been developed as a means of tackling unpredictability in some post-operative results. The purpose of the study was to compare the effectiveness of adjustable and non-adjustable squint procedures in the treatment of strabismus. We analyzed adjustable or non-adjustable squint surgery undergone in our Irish locality by retrospectively studying 27 consecutive patients at Mater Misericordiae University Hospital, Dublin. There was no significant difference (p=0.519) in the mean post-operative horizontal deviation between the adjustable group (mean=11.6 PD) and the non-adjustable group (mean=15.3 PD). We found that adjustable procedures resulted in a trend (p=0.050) towards a greater mean horizontal effect per muscle (18.9 PD per muscle) than non-adjustable procedures (mean 9.7 PD). We went on to analyze the adjustable group in order to determine the impact on outcome in those patients in whom their adjustable sutures were manipulated postoperatively. Of the 11 patients who underwent adjustable procedures, 6 subsequently had adjustments made as planned and 5 did not require adjustment. Those patients who had their sutures adjusted demonstrated a smaller mean post-operative deviation (8.5 PD) than those patients in whom their suture was not adjusted (mean=16.3 PD). Our study displays a trend that adjustable procedures are more effective in terms of the mean horizontal effect per muscle operated, and is a novel way of reporting effectiveness of strabismus procedures.

Surgical treatment of pediatric strabismus (PS): series of 148 patients

PurposeSurgical management of Pediatric Strabismus (PS) is a frequent reason of consultation in current ophthalmic practice. The aim of this study is to describe the PS epidemiology in patients consulting for surgery.MethodsThis 3 years observational descriptive retrospective study was led in ophthalmological department of university hospital. 148 patients <18 years were included. All patients received complete ophthalmological and orthoptic evaluations to determine the clinical form of strabismus.ResultsThe sex ratio was: 49.3% females vs. 50.7% of males. Exotropia was found in 46.4% of females and 53.4% of males. Esotropia was the predominant etiology (79.6%), then 19% of exotropia and 1.4% of vertical deviation. Mean age at first consultation was 6.6 years (6.3 for esotropia vs. 9.3 for exotropia). 36% had infantile forms, 26% had accommodative strabismus, 13% had an exotropia, 7% had an acquired esotropia. For amblyopia we found only 3% of severe forms whereas moderate and low forms were found in 7.4 and 11.8% of patients. Risk factors of PS identified were neurological diseases (8.1%), hyperopia (+2.33 diopters in average), complicated pregnancy (16.3%) or delivery (27%), prematurity (13 .4%), birth weight lower than 2.5 kg (14.6%) and pedigree of strabismus (74.1%).ConclusionsThe epidemiology of PS in our study is related to other European studies but different from American or Asian studies. The hypothesis are possible ethnic differences and different therapeutic management. Better understanding of these risks factors will enhance the prevention and treatment of this pathology.

Long term results of concomitant strabismus treatment based on operation preliminary modeling using three‐dimensional biomechanical eye model

PurposeTo analyze long term surgical treatment results of concomitant strabismus (CS) patients based on operation preliminary modeling in three‐dimensional biomechanical eye model (TBEM).MethodsThere were analyzed surgical treatment results in 106 patients with CS, which were operated on after the operation was preliminary modeled at TBEM ‘SEE‐KID’.ResultsOrthotropy was obtained in 54/106 patients (50.9%) at the first day postoperatively. 52/106 patients (49.1%) had residual angle of 5–10° – hypocorrection was in 44 patients, and hypercorrection was in 8 patients. 18 patients were lost to follow‐up. At 6–12 months follow‐ups ortothropy has been preserved in 53/88 patients (60.2%), and in 35/88 patients residual angle of 5–10° remained – hypocorrection was in 31 patient, and hypercorrection was in 4 patients.ConclusionsTBEM use in complex examination and treatment of CS patients allows predicting surgery result in some cases and accelerates diagnostic process, but the method needs further investigation. Particularly, extraocular muscles biomechanics needs to be more precisely estimated (degree of the muscle hyper‐ or hypofunction, movement amplitude).

Clinical observation of the graduated "hang-back" recession of superior oblique in a-pattern strabismus with superior oblique overaction

To investigate the effect and safety of the graduated "hang-back" recession of superior oblique (SO) in treatment of A-pattern strabismus with superior oblique overaction (SOOA). Retrospective study. The clinical data of 15 cases (28 eyes), who underwent graduated "hang-back" recession of SO depending on the scales of SOOA, were collected and analyzed. The principle we carried on was hang-back recession 8-10mm for SOOA+4, 6 to 8 mm for SOOA+3, 5 to 6 mm for SOOA+2 and 4 mm for SOOA+1. The pre-operative and post-operative outcomes, including the ocular alignment, ocular motility, A-pattern and objective torsion demonstrated by fundus photographs were evaluated and compared. In 15 cases (28 eyes), 2 cases had unilateral hang-back recession of SO for unilateral SOOA. Thirteen cases had bilaterally symmetric or asymmetric hang-back procedure. All the patients had no A pattern after surgery. The average difference of pre- and post-operative A-patterns were (24.5±11.9) PD and (3.2±4.2) PD in 13 cases with bilateral SOOA (t=8.01, P=0.00). The bilateral SO hang-back procedure could correct A-pattern in an amount of 21.3±10.3 PD in average. The average amount of pre- and post-operative SOOA were +3.0±2.0 and +0.5±1.0 in 28 eyes (Z=-4.70, P=0.00). Only 1 case remained residual SOOA+2.0. Fundus photos were measured by SigmascanPro5.0 program and the average pre- and post-operative torsion were +5.4°±3.9°and +0.3°±5.6° (The baseline was the line across the center of optic disc. The torsional angle was measured between the line across the fovea and and the line across the center of optic.) in 28 eyes (t=5.76, P=0.00). The average corrected torsion was 5.2°±4.8°. The pre-operative SOOA was related with the pre-operative torsion (Spearman correlation coefficient=0.47, P=0.01). The surgical amounts in 28 eyes were various from 4 to 10 mm (8±12 mm in average), which were not related with the corrected torsion (Spearman correlation coefficient=0.17, P=0.39), but related with pre-operative torsion (Spearman correlation coefficient=0.44, P=0.02). The total amounts on both eyes in patients operated by bilateral SO hang-back procedure were also not related with the corrected A-pattern (Spearman correlation coefficient=0.55, P=0.05). No case had secondary SO palsy and V-pattern after surgery. The graduated "hang-back" recession of SO is optional for treatment of mild to moderate SOOA and A-pattern. It corrected objectively in-torsion without risks of secondary SO palsy and V-pattern. It is a safe and effective SO weakening procedure. (Chin J Ophthalmol, 2016, 52: 579-583).

The Scott procedure—a new era in the treatment of incomitance?

The “Scott procedure”—simultaneous recession and resection of the same muscle, is gaining popularity in the treatment of both horizontal and vertical incomitant strabismus. It is beginning to supersede the Faden retroequatorial suture technique. We sought to investigate its effectiveness.

In vitro, ex vivo and in vivo characterization of PLGA nanoparticles loading pranoprofen for ocular administration

Pranoprofen (PF) is a NSAID considered as a safe anti-inflammatory treatment for strabismus and/or cataract surgery. The drug has been formulated in poly (lactic/glycolic) acid (PLGA) nanoparticles (PF-F1NPs with cPF 1.5mg/mL, PF-F2NPs with cPF 1mg/mL) produced by solvent displacement technique and tested the in vitro cytotoxicity, ex vivo corneal permeation, in vivo ocular tolerance and in vivo anti-inflammatory efficacy of PF-F1NPs, PF-F2NPs, in comparison to eye drops conventional dosage form (Oftalar®, PF 1mg/mL) and free drug solution (PF dissolved in PBS, 1.5mg/mL). The mean particle size of both formulations was around 350nm, with polydispersity index below 0.1, and a net negative charge of −7.41mV and −8.5mV for PF-F1NPs and PF-F2NPs, respectively. Y-79 human retinoblastoma cell line was used to evaluate the cytotoxicity of PF-F1NPs and PF-F2NPs, which were compared to blank NPs and free drug solution (PF dissolved in PBS, 1.5mg/mL). Concentrations up to 75μg/mL exhibited no toxicity to Y-79 cells, whereas at 150μg/mL a decrease of about 80% on the cell viability was observed after exposing the cells to PF-F1NPs. When treating the Y-79 cells with concentrations of PF-F2NPs between 1μg/mL to 100μg/mL, the cell viability was similar to control values after 24h and 48h of exposure. An ex vivo corneal permeation study was carried out in New Zealand rabbits. A very similar profile has been observed for the permeation of PF through the cornea when administered as eye drops and as free drug solution, which was kept much lower in comparison to PF-NPs formulations. The permeated amount of PF from the PF-F1NPs was slightly smaller than from PF-F2NPs, attributed to the increase of viscosity of the formulations with the increase of cPVA concentration. New Zealand white rabbits were also used to evaluate the irritancy of PF-F1NPs and PF-F2NPs, which demonstrated to be well-tolerated to the eye (i.e. the mean total score (MTS) was 0). PF-F2NPs exhibited the highest QP (amounts of PF permeated in the cornea) and significantly reduced the ocular edema compared to the tested formulations. The QR (amounts of PF retained in the cornea) of the PF-F1NPs was greater than that obtained for PF-F2NPs.

Application of modified Parks incision in strabismus operation under microscopy

Objective To observe the clinical effect of modified Parks incision in strabismus surgery under microscopy. Methods Ninty-six eyes of 48 cases who underwent modified Parks incision surgery for the treatment of horizontal comitant strabismus in our hospital were collected. The postoperative visual acuity, conjunctival incision, complications and eye position were observed. All the patients were followed up for 3-6 months. Results The postoperative visual acuity was the same with preoperative one, the comfort degree of patients was good, the ocular movement was normal, the bulbar conjunctival incision healing was good, and palpebral fissure area had no scar. No intraoperative or postoperative complications occurred. The eye position was normal in 88 eyes of 44 cases (91.7%), with strabismus angle within±l0Δ. The eye position was improved in 6 eyes of 3 cases (6.25%), in which angle of strabismus was ±l0Δ-±20Δ. One case (2.08%) with large angle exotropia was not healed. Conclusion Improved Parks incision under the microscopy has obvious advantages in strabismus operation with good comfort, less complications and less influence on appearance. The kind of incision is better for strabismus operation. Key words: Strabismus, comitant; Parks incision, modified; Microsurgical operation

Louis de Wecker (1832-1906) and His Innovations in Ocular Surgery.

Louis de Wecker (1832-1906) was a famous French ophthalmologist and was considered one of the greatest ophthalmologists of his time with worldwide reputation. He introduced many innovative surgical techniques such as his method for iridotomy, "anterior sclerotomy," and the so-called "de Wecker's capsular advancement" for the treatment of strabismus. He also invented surgical instruments such as "de Wecker's pince-ciseaux" and "de Wecker's double advancement hook."

Monitoring Strabismus Treatment Effectiveness in Training of the Eye Muscles

The article investigates the effect of training the eye muscles in patients with strabismus during the training and its follow-up and, using videooculography, evaluates changes in the effectiveness of eye muscle functioning. The research results indicate the possibility of adjusting the treatment of strabismus by training combined with the pro-posed control method.

Early detection and treatment of strabismus

An early diagnosis of strabismus is important in order to rule out treatable organic causes and in children, if indicated, to start as early as possible with an amblyopia treatment. Early detection will also decrease the risk for accidents secondary to diplopia, to the loss of binocular vision and to the restriction of the binocular visual field in case of esodeviations. The following therapeutic options exist: in some cases the prescription of the correct refraction will be sufficient, for small deviations a prismatic correction may allow a longstanding treatment, for larger or incomitant deviations strabismus surgery will be necessary, which nowadays can be performed using minimal-invasive technique on an outpatient base.

Botulinum Toxin for the Treatment of Tremor and Tics

The therapeutic applications of botulinum toxin (BoNT) have grown manifold since its initial approval in 1989 by the U.S. Food and Drug Administration for the treatment of strabismus, blepharospasm, and other facial spasms. Although it is the most potent biologic toxin known to man, long-term studies have established its safety in the treatment of a variety of neurologic and nonneurologic disorders. Despite a paucity of randomized controlled trials, BoNT has been found to be beneficial in treating a variety of tremors and tics when used by clinicians skilled in the administration of the drug for these hyperkinetic movement disorders. Botulinum toxin injections can provide meaningful improvement in patients with localized tremors and tics; in some cases, they may be an alternative to other treatments with more undesirable adverse effects.

Clinical feature and surgery treatment for sensory strabismus

Clinical feature and surgery treatment for sensory strabismus

ВЛИЯНИЕ МОДИФИЦИРОВАННЫХ МИКРОПРИЗМ ФРЕНЕЛЯ НА ОСТРОТУ ЗРЕНИЯ И КОНТРАСТНУЮ ЧУВСТВИТЕЛЬНОСТЬ У ДЕТЕЙ

В работе представлено исследование влияния модифицированных микропризм Френеля из набора КК-42 на остроту зрения и контрастную чувствительность у детей. Для теста отобрано 8 призм: 5 ПД; 10 ПД; 14 ПД; 18 ПД; 20 ПД; 24 ПД; 28 ПД; 30 ПД. Контрастную чувствительность исследовали с помощью Lea-numbers теста. Определено, что микропризмы снижают остроту зрения и контрастную чувствительность. Степень снижения зависит от силы микропризм– чем больше сила призмы, тем ниже острота зрения и контрастная чувствительность.

Treatment of exophthalmos and strabismus surgery in thyroid-associated orbitopathy

Endocrine orbitopathy (EO) can have important consequences, such as exophthalmos and restrictive strabismus. A retrospective study was performed of 35 patients with EO who underwent orbital decompression surgery and restrictive strabismus correction. Two surgical techniques for orbital decompression were analyzed: fat decompression by Olivari technique and three-wall bony expansion with fat decompression. Strabismus surgery was performed using adjustable or non-adjustable sutures under topical anaesthesia. Patients were divided into two groups according to the type of intra-orbital decompression performed, and the postoperative values resulting from the different fat decompression techniques were recorded. The preoperative and postoperative mean degrees of exophthalmos were 22.3 and 19.9mm, respectively, for the fat decompression group, and 24.3 and 19.8mm, respectively, for the bony expansion with transpalpebral fat decompression (combined form) group. The difference in residual prism dioptres between adjustable and non-adjustable suture techniques in patients who had previously undergone combined decompression was statistically significant. The management of patients with EO requires a multidisciplinary approach based on the collaboration of maxillofacial surgeons, ophthalmologists, and orthoptists. These results will allow the development of a more adequate strategy for the surgical treatment of restrictive strabismus in EO patients.

Surgical Treatment of Strabismus in Children

Surgical Treatment of Strabismus in Children

Effects of Bilateral Superior Oblique “Hang-Back” Recession in Treatment of A-pattern Strabismus with Superior Oblique Overaction

ABSTRACTPurpose: To investigate the efficacy and safety of bilateral hang-back recession of superior oblique (SO) muscles in the treatment of A-pattern strabismus with superior oblique overaction (SOOA).Methods: Thirty-one (31) patients (62 eyes) with A-pattern horizontal deviation and SOOA underwent hang-back recession of SO and retrospective analysis of the surgical amount of hang-back recession of SO, preoperative and postoperative A-pattern, ocular motility, and corrected objective torsion. Patients were evaluated before and 6 to 9 months after surgery.Results: The average A-pattern horizontal deviation was 27.58 ±11.47 prism diopters (PD) before surgery and 3.48 ± 3.70 PD after surgery (n=31, P<0.05). The mean corrected A-pattern was horizontal deviation 24.10 ± 10.32 PD. The average scale of SOOA on a scale of +1 to +4 was +3.05 ± 0.80 before surgery and +0.42 ± 0.50 after surgery in 62 eyes (P<0.05). The mean corrected objective torsion was 4.91°± 4.53°. The surgical amount of SO hang-back recession ranged from 4 to 10 mm (mean: 7.62 ± 1.18 mm), which was related to the preoperative A-pattern and corrected A-pattern. There were no surgical complications.Conclusions: SO hang-back recession is a safe and efficient option for A-pattern caused by SOOA.