Anomalous Head Posture Research Articles

Infantile nystagmus syndrome: An observational, retrospective, multicenter study.

This multicenter study assessed clinical and psychological aspects of infantile nystagmus syndrome (INS) focusing on its management and nonsurgical treatment. This study aimed to assess clinical features, management, relationship life, and psychological impact in a group of patients with nystagmus onset in pediatric age. This observational study included patients diagnosed with INS referred to two Italian centers from January 1, 2017, to December 31, 2020. Ophthalmologic and orthoptic features and impact of visual function on quality of life, according to nystagmus-specific nystagmus quality of life questionnaire, were analyzed within the overall sample and in any of INS subgroups. Forty-three patients were included; 65.1% of them had idiopathic INS (IINS), and 34.9% had INS associated with ocular diseases (INSOD). The median age was 15.4 years (interquartile range [IQR], 10.4 to 17.3 years), significantly different between groups (median, 15.8 years among those with IINS vs. 12.3 years among those with INSOD; p<0.001). In the INSOD subgroup, strabismus was significantly more prevalent (93.3 vs. 57.1%; p=0.017). Binocular distance best-corrected visual acuity in primary position was significantly higher in the IINS subsample (p<0.001). Such behavior was further confirmed at anomalous head position evaluation (p<0.001). At near best-corrected visual acuity assessment, differences between groups were more remarkable in primary position (p<0.001) than in anomalous head position. Contrast sensitivity showed significantly higher values in the IINS subgroup (p<0.001). The nystagmus quality of life questionnaire disclosed a significantly lower score in IINS as compared with INSOD (median total score, 90.5 [IQR, 84 to 97] vs. 94 [IQR, 83.0 to 96.5]; p<0.001). The IINS group showed significantly better ophthalmologic and orthoptic outcomes than the INSOD group. The psychological and quality-of-life impact was instead significantly greater in the IINS group. To the best of our knowledge, this is the first multicenter study investigating the clinical features of IIN and comparing the two main subgroups, IINS and INSOD.

An Alternative in Managing Duane Retraction Syndrome Type I Using Modified Nishida Procedure: A Case Report

Introduction : Various surgical approaches have been proposed to address the challenge in managing abduction deficit in Duane Retraction Syndrome (DRS) Type I, with no clear guidelines to achieve optimal result. This report aims to describe the outcome of combining medial rectus (MR) recession and modified Nishida procedure to improve abduction in DRS Type I.&#x0D; Case Illustration : Twenty six year-old female came with inability to abduct her left eye (LE) since early childhood and an abnormal left head turn. No complaints of double vision nor visual impairment. There was -5 abduction on LE with a noticeable narrowing of vertical palpebral fissure during adduction. Prism alternate prism cover test shared a 30 PD esotropia with normal anterior and posterior segment. Patient was assessed with DRS Type I of LE and managed with 5mm MR recession combined with modified Nishida procedure (vertical rectus transposition without tenotomy and muscle splitting). On postoperative day 1 and last follow-up (1 year), the alignment was ortophoric, abduction improvement of -2, and diminished anomalous head posture.&#x0D; Discussion : Although studies have only reported successful cases of modified Nishida procedure in CN VI palsy, it can be assumed that the procedure can also be implemented to treat lateral rectus muscle innervation abnormality such as in DRS type I. Surgical intervention may not normalize abduction deficit. However, the procedure successfully corrects ocular alignment, eliminates anomalous head posture, and able to improve abduction with no complications.&#x0D; Conclusion : Modified Nishida procedure can be implemented as an alternative in managing DRS type I with relatively satisfactory result.

Клинический случай применения ботулинического токсина типа А без гемагглютининового комплекса у пациента с редким типом нистагма (spasmus nutans)

This article demonstrates a clinical case of botulinum toxin type A without a hemagglutinin complex application in a patient with a rare type of nystagmus. Patient L. 1 year 9 months old with manifestations of spasmus nutans(oscillatory eye movements, head nodding, and anomalous head position), who underwent chemodenervation of oculomotor muscles using botulinum toxin type A without hemagglutinin complex. The use of chemodenervation in patients with nystagmus is one of the methods of effective treatment of this pathology. Key words: nystagmus, chemodenervation, botulinum toxin type A, spasmus nutans

Nystagmus in Children - a Survey

Nystagmus describes an involuntary, periodic movement of one or both eyes. About 1/600 children and adolescents have nystagmus, most of them idiopathic infantile nystagmus (IIN), also called "congenital nystagmus", which can be caused by mutations in the FRMD7 gene. Other frequent forms of nystagmus are latent nystagmus, which is usually associated with infantile strabismus, and nystagmus associated with albinism. Sometimes difficult to distinguish in young infants is a sensory nystagmus, where a defect in the visual system reduces vision and causes nystagmus. Causes include retinal dystrophies, congenital stationary night blindness and structural ocular defects including optic nerve hypoplasia or dense bilateral congenital cataracts. Unilateral nystagmus can be the sign of an anterior visual pathway lesion. Seesaw nystagmus may be associated with suprasellar and mesodiencephalic lesions and - rarely - with retinal dystrophies.The ophthalmology plays a key role in identifying the form of nystagmus. Children with new onset nystagmus, with spasmus nutans, with vertical or unilateral nystagmus and those with seesaw nystagmus require neurologic evaluation including imaging of the brain.The treatment of nystagmus depends on the underlying cause. Even minor refractive errors should be corrected, contact lenses offer advantages over glasses.Gabapentin and memantine, possibly also carbonic anhydrase inhibitors, are effective in treating IIN, nystagmus in albinism and sensory nystagmus. Nevertheless, pharmacologic treatment of nystagmus is rarely used in children; the reasons are the limited effects on vision, the need for lifelong therapy, and potential side effects. Eye muscle surgery (Anderson procedure, Kestenbaum procedure) can correct a nystagmus-related anomalous head posture. The concept of "artifical divergence" of Cüppers may help to decrease nystagmus intensity in patients whose nystagmus dampens with convergence. The four-muscle-tenotomy, which involves disinsertion and reinsertion of the horizontal muscles at the original insertion of both eyes, has a proven but limited positive effect on visual acuity.

Anomalous head posture

Intermittent exotropia (IXT) usually presents with occasional outward deviation of the eye, asthenopia, headache, diplopia, or photophobia. We report here an unusual presentation of IXT in a 21-year-old man, with an anomalous head posture (AHP) of face rotation towards left as the primary symptom. On examination, there was lateral gaze incomitance, and improved fusion range in dextroversion explained his AHP.

Demographic and Clinical Characteristics of 600 Children With Nystagmus.

To characterize a large, international cohort of children with nystagmus. Data were collected from a single-center, prospectively developed database on patients with nystagmus. Outcome variables for this study included: (1) demographic characteristics, (2) nystagmus type, (3) clinical characteristics, (4) associated ophthalmic conditions, (5) associated non-ophthalmic conditions, (6) special testing findings, and (7) treatments. Six hundred patients from 38 states and 30 countries were included. Age ranged from birth to younger than 18 years (mean: 15.2 years), 58% were female, 55% were race other than White, 75% had infantile nystagmus syndrome, 17% had neurologically significant nystagmus, 7% had fusion maldevelopment nystagmus syndrome, 64% had strabismus, 56% had an anomalous head posture, 94% had a significant refractive error, 64% had an associated ophthalmic abnormality (excluding ametropia), and 45% had an associated systemic condition. Special testing showed abnormalities in 67% and 95% had treatment directed at their nystagmus. The most common diagnosis in this cohort is neurologically non-significant infantile nystagmus syndrome. Eye movement recordings provide a path toward accurate diagnosis and classification. There was a high prevalence of underlying ocular and/or systemic conditions requiring ophthalmic special testing as part of a diagnostic routine. Clinical treatments are available to most patients. [J Pediatr Ophthalmol Strabismus. 2023;60(6):406-410.].

High-dose medialis recession in latent nystagmus

Large muscle recessions reduce anomalous head turn (AHT) in infantile nystagmus syndrome (INS). Their quantitative effect to reduce AHT in fusion maldevelopment nystagmus syndrome (FMNS) is unknown. To evaluate the reduction of AHT by large medial rectus muscle recession in patients with FMNS. We analyzed data of 12patients with pure FMNS who received large medial rectus muscle recessions on the sound eye or only eye between 2014 and 2019. Medians and ranges (min-max) were: age at surgery 14years (3-43 years); decimal BCVA sound eye/fellow eye 0.56 (0.4-1.0)/0.01 (0-0.4); AHT at 5 m/0.3 m fixation distance 35° (15-45°)/20° (0-45°); amount of recession 13 mm (11.5-15 mm); follow-up13 (4-39) months. At the final visit, AHT at 5 m/0.3 m was 10° (0-20°/0-15°). The individual reduction of AHT at 5 m amounted to 25° (8-35°) without any overcorrection. The available visual field of functionally monocular patients increased correspondingly. Slight overcorrection at 0.3 m occurred in 2cases. Adduction of the sound eye was limited to 25e-40°). BCVA and anomalous head posture in vertical and frontal planes did not improve. Large medial rectus muscle recession on the sound eye improves AHT in FMNS by asimilar amount compared to INS and the available visual field of functionally monocular patients.

Accuracy and Correlation of the Kinect-Based Semi-Automatic Scoring Method for Measuring Anomalous Head Posture as Compared to the CROM® Device.

To determine the reliability of the Kinect-based semi-automatic scoring method (KSSM) using Kinect for Windows v2 for head posture compared to the cervical range-of-motion (CROM) device. Head positions between -40° and +40° of chin up/down (X), head turn (Y), and lateral tilt (Z) were measured in 10° increments in healthy volunteers. Their head positions were simultaneously measured using the KSSM and CROM. The following four points were analyzed: the success rate of the KSSM, the correlation between the two methods, the comparison of results by 95% limits of agreement (LA), and proportional error at 95% LA. The measurability of the KSSM for all positions within ±30° of the X, Y, and Z axes was 100%. The correlations for both methods were 0.979 (95% CI: 0.967-0.987), 0.985 (0.976-0.991), and 0.988 (0.981-0.993) for the X-, Y-, and Z-axes, respectively. The simple linear regression analysis equations for 95% LA were Y=-0.024X-0.452 for X axes, Y=0.024X-0.363 for Y axes, and Y=-0.045X+0.217 for Z axes (95% confidence interval for each axis: -0.055-0.007, -0.006-0.050, and -0.071-0.018). However, the proportional biases were small because the predictive values of the differences in head positions from -40° to 40° determined by the equations were within ± 5° for chin up/down and within ± 3° for head tilt. Head posture measurements using the KSSM and CROM were found to be similar when used in clinical settings.

Surgical Treatments to Improve Visual Acuity in Infantile Nystagmus Syndrome: A Report by the American Academy of Ophthalmology

To review the literature on the efficacy of surgical procedures to improve visual acuity (VA) in patients with infantile nystagmus syndrome (INS). Literature searches were last conducted in January 2022 in the PubMed database for English-language studies with no date restrictions. The combined searches yielded 354 abstracts, of which 46 were reviewed in full text. Twenty-three of these were considered appropriate for inclusion in this assessment and were assigned a level of evidence rating by the panel methodologist. One included study was a randomized trial; the remaining 22 were case series. The 23 studies included children and adults with INS and a variable proportion with anomalous head position (AHP), strabismus, and sensory diagnoses. The surgical interventions evaluated included large recessions, tenotomy and reattachment (TAR), myectomy with or without pulley fixation, and anterior extirpation of the 4 horizontal rectus muscles, as well as various procedures to correct an AHP in which VA was reported as a secondary outcome. The data were mixed, with improvements in binocular best-corrected visual acuity (BCVA) ranging from no improvement to 0.3 logarithm of the minimum angle of resolution (logMAR), or 3 lines. (Most studies were in the range of 0.05-0.2 logMAR.) Statistically significant improvement in VA was noted in 12 of 16 studies (75%) that performed statistical analyses, with no clear advantage of any single procedure. Complications and reoperations were lowest in patients who underwent TAR and highest in those who underwent myectomy or anterior extirpation. The best available evidence suggests that eye muscle surgery in patients with INS results in a modest improvement in VA. Proprietary or commercial disclosure may be found after the references.

Аномальное положение головы: новая парадигма

Purpose. To determine the most common ocular causes and types of anomalous head position and give details of their functional features. Material and methods. The research included 105 patients with an anomalous head position. Depending on the oculomotor pathology, patients were divided into 6 groups. 1st group – 10 patients with Brown syndrome, 2nd group – 20 patients with Duane syndrome of types 1 and 2, 3rd group – 30 patients with nystagmus, 4th group – 30 patients with n. abducensparalysis, 5th group – 15 patients with n. trochlearisparalysis, and control 6th group – 20 patients with one of the above pathology, but without anomalous head posture (AHP). Results. Out of 105 patients with AHP, 83.8% had both fusion and stereopsis. There was no statistical difference in the rate of fusion or stereopsis among the different AHP types (p=0.580). The control group showed accurately low scores of stereopsis and fusion loss (5.3%) (p=0.001). The overall incidence of amblyopia in all groups of patients with AHP (with Brown, Duyane syndrome, with nystagmus by 3.7 times, with paralysis and paresis of n. abducensand n. trochlearis) is statistically significantly lower (p&lt;0.001) than in the control group. Conclusion. The most common ocular causes of anomalous head position are nystagmus and paralysis of the abducens nerve, as well as Duane syndrome and paralysis of the trochlear nerve. Head rotation is most commonly associated with congenital nystagmus, Duane syndrome, and n. abducens paralysis and paresis. Head tilt or various combinations of head tilt with a raised chin is most characteristic of n. trochlearis paralysis and paresis and Brown syndrome. AHP formation is a «protective» mechanism in terms of developing amblyopia and loss of binocular single vision. Key words: abnormal head position, binocular vision, stereopsis, amblyopia.

Single-arm tool for assessment of anomalous head posture.

Anomalous head posture (AHP) measurement is crucial in the management of nystagmus and incomitant strabismus and also during follow-up assessments. The types of AHP include chin posture, head tilt, and face turn. Goniometer is a low-cost tool widely used to measure head posture. This has two arms: one reference arm and one measuring arm. The drawback of this device is that the examiner has to maintain the reference arm exactly parallel or perpendicular to the floor and the other arm has to align the AHP. Since not all the examiners are comfortable in aligning both the arms simultaneously, the measurements obtained by a goniometer end up being less accurate. A device named cervical range of motion (CROM) is more reliable but expensive. There is an iOS application created for the purpose of head posture assessment, but an iPhone is expensive. To demonstrate a low-cost, innovative, reliable single-arm tool (SAT) for assessment of AHP. A clinometer is a device that is used to measure the heights of buildings. In this device, the gravitational force of the earth determines the reference line. We have modified a clinometer into a SAT by incorporating a long plastic arm to it, which is used to measure head tilt and chin up/down measurements. For the purpose of face-turn measurement, we modified a compass for direction into another type of SAT by fitting a yoke dial and a long plastic arm to measure face turn. Here, the principle is to have the line of direction as a reference. The direction of the patient's seating arrangement is determined and taken as the reference direction. The amount of the patient's face turn is measured by finding out the angle between reference direction and direction of the nose. This video shows the method of making SAT in a do-it-yourself manner and also demonstrates the method of measuring AHP. SAT is a reliable and low-cost device. https://youtu.be/UwoHARok85c.

Demographic and clinical characteristics of 600 children with nystagmus

To characterize a large, international cohort of children with nystagmus.Data were collected from a single-center, prospectively developed database on patients with nystagmus. Outcome variables for this study included: (1) demographic characteristics, (2) nystagmus type, (3) clinical characteristics, (4) associated ophthalmic conditions, (5) associated non-ophthalmic conditions, (6) special testing findings, and (7) treatments.Six hundred patients from 38 states and 30 countries were included. Age ranged from birth to younger than 18 years (mean: 15.2 years), 58% were female, 55% were race other than White, 75% had infantile nystagmus syndrome, 17% had neurologically significant nystagmus, 7% had fusion maldevelopment nystagmus syndrome, 64% had strabismus, 56% had an anomalous head posture, 94% had a significant refractive error, 64% had an associated ophthalmic abnormality (excluding ametropia), and 45% had an associated systemic condition. Special testing showed abnormalities in 67% and 95% had treatment directed at their nystagmus.The most common diagnosis in this cohort is neurologically non-significant infantile nystagmus syndrome. Eye movement recordings provide a path toward accurate diagnosis and classification. There was a high prevalence of underlying ocular and/or systemic conditions requiring ophthalmic special testing as part of a diagnostic routine. Clinical treatments are available to most patients. [J Pediatr Ophthalmol Strabismus. 20XX;X(X):XX-XX.].

Dissociated vertical deviation: Simplified

Abstract Dissociated vertical deviation (DVD) is not a well-understood ocular motility disorder. It is defined as an intermittent anomaly of a non-fixing eye consisting of upward excursion, ex-cyclotorsion, and lateral deviation. It can present as latent or manifest deviation. It is usually bilateral, asymmetrical, and often associated with latent nystagmus and infantile esotropia. In unilateral cases, it can be associated with amblyopia. Binocular vision is usually absent in these patients. There are huge variations in the measurements of DVD, as it becomes visible only with one eye covered, hence making quantification of its magnitude difficult. Therefore, choosing an adequate management option is difficult. Management options include both conservative as well as surgical treatment. Conservative management is done with spectacles correction to encourage fusion. Surgical management is indicated in large, frequent DVD or with anomalous head posture. Surgical options commonly adopted are superior rectus recession with or without posterior fixation sutures. Different surgical approaches to DVD are currently being used but no recommended guidelines are available, hence is based on the amount of deviation and experience of a surgeon.

Analysis of anomalous head posturing in patients with infantile nystagmus syndrome

To investigate anomalous head posturing in patients with INS. This was a prospective, cohort analysis of clinical and anomalous head posture (AHP) data in 34 patients with INS and an AHP. Particular outcome measures included measurement of AHP in three dimensions of pitch (anterior posterior flexion/extension), yaw (lateral rotation), and roll (lateral flexion) during best-corrected binocular acuity testing and during their subjective sense of straight. Patients were also queried as to their subjective sense of head posture in forced straight position and in their preferred AHP. The paired t test was used to determine significance in differences between measures. A total of 34 patients (19 males [56%]) 9-56years of age (mean, 16.5±6) were included. Associated systemic or ocular system deficits were present in 30 patients (88%). AHP during best-corrected visual acuity testing averaged 16.5°±8.20° (range, 10°-51°), which was significantly different from the mean voluntary "comfortable" position only in the pitch and roll directions (P<0.001). There was a significant noncongruous response during subjective response to head posturing with most sensing their head as "crooked" (76.5%) when manually straightened (P=0.001). The clinical AHP of patients with INS exists in all three spatial dimensions of pitch, yaw, and roll. Although the visual system may be causally related to the onset, amount, and direction of a compensatory AHP in patients with INS, its persistence over time or after surgical intervention is likely due to a combination of visual system (eg, nystagmus, strabismus) and nonvisual system (egocentric and musculo-skeletal) factors.

Clinical and Electrophysiological Outcomes After Eye Muscle Surgery in 81 Adults With Infantile Nystagmus Syndrome.

To characterize the effects of eye muscle surgery on patients older than 18 years with infantile nystagmus syndrome (INS) who have had only optical treatment. This was a prospective, single-center, interventional case series analysis of clinical and electro-phyisological data before and after surgery. Outcome measures included: clinical characteristics, surgical procedure, and preoperative and postoperative binocular best corrected visual acuity (BCVA) in the null position, anomalous head posture (AHP), contrast sensitivity, strabismic deviation, and nystagmus acuity function (NAFX). Postoperative data used were collected for a minimum of 12 months after surgery. Parametric and non-parametric statistical analysis of the outcome measures was performed. Ages ranged from 18 to 72 years (average: 36 years) and follow-up from 12 to 74 months (average: 26 months). A surgical algorithm of nine separate procedures involving at least two recti muscles on each eye was used for each patient. Most patients had associated systemic and/or ocular diagnoses, including albinism (35%), amblyopia (23%), optic nerve or retinal disorders (48%), refractive error (80%), AHP (44%), aperiodicity (27%), and strabismus (69%). There were no serious surgical complications, with a reoperation rate of 12%. There were significant group mean increases in BVCA, AHP, contrast sensitivity, strabismic deviation, and NAFX after surgery. Sixty percent of patients who were legally ineligible for driving prior to surgery became eligible after eye muscle surgery. Adult patients with INS showed sustained improvement in many afferent and efferent measures of visual function after eye muscle surgery. [J Pediatr Ophthalmol Strabismus. 2021;58(2):93-104.].

Bilateral hypotropic dissociated vertical deviation: a case report\xa0

BackgroundHypotropic dissociated vertical deviation (DVD) is a special form of strabismus characterized by a slow drift of the non-fixating eye when the other eye is fixating on a target. In contrast to hypertropic DVD, which is common, hypotropic DVD is exceedingly rare and seldom reported in previous literature. In this case, we report the clinical features of a rare case of a Syrian child with bilateral hypotropic DVD accompanied by manifest latent nystagmus and intermittent exotropia.Case presentationA 4-year-old Syrian Arab girl presented with intermittent exotropia of both eyes since the age of 7 months, without any prior treatment. The fixation was alternating. She had manifest latent nystagmus in both eyes and anomalous head posture. She had bilateral hypotropic DVD in both eyes which only appeared when covering each eye. The patient underwent bilateral lateral rectus recession with posterior fixation and bilateral inferior oblique recession. Three months after surgery, she was orthophoric in the primary gaze position with a normal head posture. No alteration of the appearance of the hypotropic DVD was observed after the surgery.ConclusionThis is a rare case of hypotropic DVD showing bilateral hypotropic DVD with different characteristics from those previously reported cases (bilateral hypotropic DVD with intermittent exotropia, dissociated horizontal deviation, manifest latent nystagmus, and bilateral inferior oblique overaction). The hypotropic DVD only appeared when covering each eye, and thus there was no need for surgery. Moreover, the inferior oblique recession did not seem to negatively affect the appearance of the eyes.

Surgical Management of Complex Anomalous Head Posture in Idiopathic Infantile Nystagmus

Idiopathic infantile nystagmus (IIN) is usually associated with a null zone, which is the zone of minimal nystagmus intensity. An anomalous head posture (AHP) is adopted to shift the null zone from an eccentric position to primary position. A complex AHP may include head position involvement in different ocular axes-namely face turn, chin elevation or depression and head tilt or a combination of these. Surgically, various procedures have been described for correction of this condition. We evaluated 2 children aged six and ten years, who presented with shaking of eyes along with presence of a complex AHP. First child had 20 degrees right face turn, 20 degrees right head tilt and 10 degrees of chin elevation. She underwent a combination of 2 procedures-augmented Anderson’s procedure for correction of right face turn and modification of Kestenbaum procedure for right head tilt along with bilateral IR recession, for correction of chin elevation. Postoperatively, AHP was satisfactorily corrected to 5 degrees face turn and minimal head tilt, and it remained stable for one year. The second child had left face turn 15 degrees, with right head tilt of 20 degrees and chin depression 10 degrees. He underwent a combination of 2 procedures-augmented Anderson’s procedure for correction of left face turn and modification of Kestenbaum procedure for right head tilt along with bilateral SR recession, for correction of chin depression. Postoperatively, AHP was satisfactorily corrected to 5 degrees face turn and minimal head tilt, which remained stable over a period of one year. In both cases, AHP was corrected by operating on only 2 muscles in each eye (one horizontal and one vertical) at a time. As both cases presented with combination of both torsional and vertical components of AHP, we decided to treat them both by surgery on a single vertical rectus muscle bilaterally to correct the chin position (elevation or depression), as well as torticollis (transposition of vertical recti, either nasally or temporally as needed). Since a third rectus muscle was not operated upon, there was a lesser possibility of developing anterior segment ischaemia. Additionally, as all components of AHP were corrected in one session, need for a second procedure under general anaesthesia to correct residual AHP was avoided in both cases.

Eficacia y complicaciones de las transposiciones musculares en el síndrome de Duane con esotropía

ObjectiveTo study the long-term efficacy and the complications of several transposition techniques for the treatment of Duane syndrome. These included, full vertical rectus transposition, partial vertical rectus transposition, transposition without muscle disinsertion, and superior rectus transposition. Material and methodsA retrospective study of the patients diagnosed with Duane syndrome, and who underwent any of the different transposition techniques associated or not to the medial rectus recession with a follow-up longer than 12 months. A good result was considered a final deviation≤10 prism dioptres (pd) in primary position, anomalous head posture<10°, and an improvement of the abduction without diplopia. ResultsSeven cases were included (6 women, 6 unilateral), and a mean age of 37.71 years. Pre-operative central gaze esotropia of 28±11.68pd decreased to 6±4.62pd at the final visit (P=.009). The anomalous head posture decreased in 6 patients, and the abduction improved one degree from −3.14 to −2.14 (mean). An induced vertical deviation≤8pd was observed in 4 cases. None experienced diplopia at the final visit. The percentage of reoperations was 71.42%. Only 28.57% had a favourable outcome with a single surgery, which increased to 71.42% with further surgeries at the final follow-up. Mean evolution time was 52±31.65 months. ConclusionsVertical rectus transpositions in Duane syndrome with moderate or severe clinical signs have only been effective in a small percentage of the cases. Most of them required further surgeries to resolve the complications or the under-corrections.

Self-grading effect of inferior oblique myectomy and recession

To evaluate the outcomes of inferior oblique (IO) weakening surgery, whether recession or myectomy, and to assess the dose-response relationship and correlation with angle of preoperative hypertropia. The medical records of all patients with vertical deviation in primary gaze who underwent unilateral IO-weakening surgery, either recession or myectomy, at Boston Children's Hospital over an 8-year period with a minimum postoperative follow-up of 1month were reviewed retrospectively. Outcome measures were effect of IO weakening surgery on vertical deviation in primary gaze and its correlation with the preoperative angle of hyperdeviation. Secondary outcomes included resolution of abnormal head posture, reduction of ocular torsion, and postoperative under- and overcorrection. A total of 94 patients were identified (mean age at surgery, 29.3±19.8years; range, 1-69). The mean postoperative follow-up period was 17.2±15months. IO recession was performed in 30 patients; IO myectomy, in 64. Surgical success in primary position was achieved in 72 patients (77%), with resolution of anomalous preoperative head posture in 93%. The mean effect on alignment in primary position was 11.3Δ ± 6.8Δ. The response to IO-weakening surgery was strongly correlated with the preoperative hyperdeviation for both recession (R2=0.53) and myectomy (R2=0.87). As with other types of strabismus surgery, IO weakening has a "self-grading" contribution, in which the surgical effect strongly correlates with the magnitude of preoperative deviation. A large range of vertical misalignment can be corrected with the same surgical approach.

Case Report of Anomalous Head Posture Correction with Low Vision Aid Using Virtual Reality

Case Report of Anomalous Head Posture Correction with Low Vision Aid Using Virtual Reality