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Low contrast acuity (LCA) and near stereoacuity (NS) testing are integral to the comprehensive assessment of sensory visual function in children. However, routine ophthalmological evaluations seldom take these measures into consideration. Additionally, there is limited literature regarding the normative values of these parameters in children.This study investigated LCA and NS measures and their variability in children with normal visual acuity. The aim was to provide a benchmark for distinguishing normal measures from abnormal ones.A prospective observational study was conducted in primary and secondary schools across North India. The participants numbered 240 children, aged between 3 and 15 years. They were split into 12 smaller groups of 20 participants in each age group. Only participants with normal monocular uncorrected visual acuity, no refractive error, normal birth history, and no systemic ailments, were recruited. All the participants underwent a complete ophthalmic examination and non-cycloplegic retinoscopy. LCA was measured, using the low contrast Lea number chart at three metres. NS was measured using the Randot® stereo test at 40 cm.The percentages of males and females, were found to be 55%, and 45%, respectively (p = 0.093). The mean NS was found to be 38.7 ± 11.5 arcsecs in the 3-9-year age group, and 26.7 ± 5.6 arcsecs in the 9-15-year age group (LCA and NS mature gradually during childhood. LCA stabilises after the age of 8, while NS stabilises after the age of 9.

In clinical practice Cerebral Visual Impairment (CVI) is typically diagnosed by observation of abnormal visually guided behaviors which indicate higher visual function deficits (HVFDs) suggesting abnormal brain development or brain damage in a child with a suitable clinical history. HVFDs can occur even in the presence of good visual acuity and may remain undiagnosed because the good visual acuity does not prompt further investigation. This leads to a lack of understanding of the child’s visual perceptual difficulties. In a prospective study, we determined the spectrum of HVFDs in a group of children with history suggestive of brain damage or disruption of brain development and an independent diagnosis of CVI in comparison with typically developing children with a structured 51 question inventory, the Higher Visual Function Question Inventory (HVFQI-51) adapted from the Cerebral Vision Impairment Inventory, CVI-I. Here, we show that the HVFQI-51 can detect a range of HVFDs in children with CVI with good visual acuity and clearly distinguishes these children from typically developing children. HVFDs in our study group could mostly be attributed to dorsal stream visual processing dysfunction though the spectrum varied between children. We report on the inclusion of the “not applicable” response option in analysis providing a picture of HVFDs more in tune with the overall disability of each child. We also propose a subset of 11 questions (Top-11) which discriminate between children with CVI vs. behaviors seen in typical children: this provides both a potential screening tool for initial assessment of HVFDs and a measure of CVI-related impairment, and needs further validation in a secondary independent sample.

Cerebral Visual Impairment (CVI), vision loss due to brain injury in early childhood, is the leading cause --- approximately 40% --- of bilateral visual impairment in children from industrialized countries and is the most rapidly growing cause among children in developing countries. Typical causes of CVI include abnormal brain development or brain damage, often consequential to birth-related complications such as hypoxic ischemic encephalopathy, meningitis, hydrocephalus, and head injury. The current gold standard for clinical diagnosis require a trained clinician to administer visual-motor integration tests in conjunction with a thorough review of a patient's clinical history. This approach does not scale to meet the needs of undiagnosed children with CVI. Recently, non-invasive screening methods such as administering a higher visual function question inventory (HVFQI), have been shown to accurately capture the observations of teachers and guardians of children. Analysis of those observations has been shown to have very high correlation with visual-motor integration tests (p values The HVFQI web app is an online clinical diagnostic tool and database system designed to gather participant responses to over 50 questions and follow-up questions. No personally identifying information is stored in the database. The web app provides three critical functions: (1) scalable and accurate administration of the HVFQI; (2) global coordination of screening efforts; and (3) a consolidated database for efficacy analysis studies and rapid iteration of the HFVQI to maximize impact, accuracy, and accessibility. The HVFQI consists of a question inventory, a scoring rubric, and a conditional intervention strategy list. The question inventory is carefully curated and designed to capture observations from teachers and guardians that may indicate specific pediatric higher visual function deficits (HVFDs). In many instances HVFDs are accompanied by normal visual acuity, making diagnosis difficult, and requiring multiple questions to elicit HVFDs. These questions are presented at random to avoid leading the participant. The responses are scored according to the HVFQI scoring rubric, which indicates which HVFDs may be present, and relevant intervention strategies. The rubric responds to varying degrees of affirmative responses in a 5-category Likert scale, which includes 3 non-applicable responses with different causes. The rubric also responds to categorical responses for multiple-choice and multiple-answer questions. The web app prepares a report of relevant intervention strategies for the participant, along with the questions and responses as context. The web app is also designed to coordinate international clinical efforts. The web application administrators, led by a superadministrator, can create, manage, and remove centers and staff corresponding to physical (or virtual) locations as demand grows. Each center has a local administrator that can authorize staff to administer the HVFQI, interpret and discuss the results and relevant strategies with participants. The data is stored in a central secure database, accessible only to authorized researchers, and the site administrator. All data are anonymous and non-personally identifying. Authorized researchers can analyze the results for their local centers to estimate efficacy and submit suggestions to update the HVFQI to meet the needs of local participants. Researchers authorized by the super-administrator have full access to the entire database and can perform global analysis for rapid improvement. The HVFQI web app is the result of a collaboration between the SeeLab of the Smith-Kettlewell Eye Research Institute, and the Kulkarni Group of the Computer Science Department at San Francisco State University.

Purpose The PowerRef 3 is frequently used in studying the near triad of accommodation, vergence and pupil responses in normal and clinical populations. Within a range, the defocus measurement of the PowerRef 3 is linearly related to the eye's defocus. While the default factory‐calibrated slope of this relation (calibration factor) is 1, it has been shown that the slope can vary across individuals. Here, we addressed the impact of changes in viewing distance, age and defocus of the eye on the calibration factor. Methods We manipulated viewing distance (40 cm, 1 m and 6 m) and recruited participants with a range of accommodative capabilities: participants in their 20s, 40s and over 60 years old. To test whether any effect was larger than the range of measurement reliability of the instrument, we collected data for each condition four times: two in the same session, another on the same day, and one on a different day. Results The results demonstrated that viewing distance did not affect the calibration factor over the linear range, regardless of age or uncorrected refractive error. The largest proportion of the variance was explained by between‐subject differences. Conclusions Calibration data for the PowerRef 3 were not sensitive to changes in viewing distance. Nevertheless, our results re‐emphasise the relevance of calibration for studies of individual participants.

Purpose We sought to characterize neural motion processing deficits in children with cerebral visual impairment (CVI) who have good visual acuity using an objective, quantifiable method (steady-state visual evoked potentials [SSVEPs]). Methods We recorded SSVEPs in response to three types of visual motion - absolute motion and more complex relative and rotary motion, comparing them to form-related vernier and contour responses. We studied a group of 31 children with CVI diagnosed via detailed clinical examinations and 28 age-matched healthy controls. Results Using measurements made at the appropriate response harmonics of the stimulation frequency, we found significant deficits in cerebral processing of relative and rotary motion but not of absolute motion in children with CVI compared with healthy controls. Vernier acuity, in keeping with good recognition acuity in both groups, was not different, nor were contour-related form responses. Conclusions Deficits for complex motion but relative sparing of elementary motion and form-related signals suggests preferential damage to extra-striate visual motion areas in children with CVI. The fact that these preferential losses occur in the absence of significant acuity loss indicates that they are not secondary to reduced visual acuity, but rather are an independent vulnerability in CVI. These results corroborate parental and caregivers' reports of difficulties with tasks that involve motion perception in children with CVI.

Background Children and young people (CYP) living with diabetes require integrated child-centered care. We hypothesized that suboptimal uptake to diabetic retinopathy screening in CYP may be partly related to the degree of services integration. We investigated the structure of the current pediatric diabetic eye care pathway and associations between service-level characteristics and screening uptake. Methods A quality improvement project between January and May 2017 comprising a survey of practice of all 158 pediatric diabetes services (pediatric diabetes units, PDUs) across England and secondary data analysis of routinely collected service data. Generalized linear models for proportional responses were fitted to investigate associations between reported PDU characteristics and screening uptake. Results 124 PDUs (78%) responded. In 67% (n = 83), patients could be referred directly to screening programs; the remainder relied on primary care for onward referral. 97% (n = 120) considered eye screening results useful for counseling patients but only 65% (n = 81) reported it was "easy" to obtain them. Factors independently associated with higher screening uptake were a higher proportion of patients referred from primary care (OR = 1.005; 95%CI = 1.004-1.007 per 1% of increase), absence of "out-of-catchment area" patients (OR = 1.13; 95%CI = 1.04-1.22), and easy access to eye screening results (OR = 1.45; 95%CI = 1.34-1.56). Conclusions There is limited direct communication between the services involved in diabetic eye care for CYP in England. This risks reducing the effectiveness of diabetic retinopathy screening. Similar vulnerabilities are likely to exist in other countries where retinopathy screening for CYP has been "bolted on" to provision for adults.

Purpose: To assess the effects of systemic propranolol on refractive error in infants with periocular capillary hemangiomas. Methods: A single-center study of consecutive patients with capillary hemangiomas treated with systemic propranolol. Refractive data were analyzed using Long’s matrix formalism and the methods of Harris and Kaye. Results: Seventeen patients were included. At 6 months postoperatively, hemangioma size reduced from 3,214 to 1,806 mm 3 (standard deviation: 4,122 to 2,441). Mean refractive error in the affected eye significantly reduced: −1.25/0.38 × 36 (95% confidence intervals: −5.08/1.20 × 90 to 1.64/1.43 × 180, P = .048) with a smaller change ( P = .06) in the unaffected eye of −1.01/+0.31 × 3.16 (95% confidence intervals: −4.02/+1.12 × 180 to +1.49/+0.51 × 90). Conclusions: Propranolol produced a clinically significant reduction in the infants’ refractive error and anisometropia. The reduction in the total refractive error and anisometropia has not been evident in previous analyses, which have concentrated on the change in the “cylinder” as the principal outcome measure. [J Pediatr Ophthalmol Strabismus 2014;51(3):165–170.]

Purpose We measure neural responses associated with form and motion processing in children with anisometropia before and after treatment with spectacles and occlusion. Methods In this prospective, case-control treatment study, 10 children with anisometropia and amblyopia and 16 age-matched visually normal children participated. Steady-state visual evoked potentials (VEP) were recorded from electrodes over the occipital cortex. The visual stimulus comprised a horizontal bar grating into which Vernier offsets were introduced and withdrawn periodically at 3.75 Hz. The VEP amplitude at 3.75 Hz (first harmonic [1F]) and 7.5 Hz (second harmonic [2F]) were recorded to index the sensitivity of form/position-sensitive versus motion/transient-sensitive neural populations, respectively. Response amplitude at 1F and 2F were recorded over a series of 10 logarithmically spaced offset sizes before and after treatment. Main outcome measures are VEP amplitude versus displacement functions, interocular response amplitude differences. Results After relaxing into spectacles (minimally-treated state), form/position-sensitive responses in the dominant/less ametropic eye of the children with anisometropia were larger and responses in the more ametropic eye were smaller than those of controls. Motion-transient responses were equal to those of controls in the less ametropic eye, but were smaller than controls in the more ametropic eye. After treatment, responses did not differ from those of controls. Conclusions Form and motion responses are differentially susceptible to neural deprivation via optical blur. Form responses are more plastic than motion responses in minimally-treated children with anisometropic amblyopia. Most treatment effects occurred above threshold range, suggesting some treatment effects are not detected clinically.

Presentation of suspected pediatric uveitis: Pediatric uveitis is usually managed in specialized ophthalmic centers in the UK. Meaningful data acquisition in these clinics may be helpful in clinical governance, and healthcare planning in a specialty that is gradually changing due to changes in treatment choices.Retrospective analysis of prospectively acquired data in the Liverpool pediatric uveitis database was performed.Analysis of our data, based on 147 patients, with a mean age of 10 years, indicated a female to male ratio of 2:1. 99% of patients were Caucasian. Our data indicates 86% of all patients attending the uveitis clinic were diagnosed with juvenile idiopathic arthritis, followed by intermediate uveitis 5% and idiopathic uveitis 4%. 46% of patients required treatment. Systemic treatment included methotrexate (34%), prednisolone (14%), etanercept (6%), ciclosporin (6%), mycophenolate (3%), and infliximab (1%). Severe visual loss (defined by counting fingers or below vision) was seen in 10 eyes despite appropriately treated chronic uveitis.Our data shows uveitis-related ocular morbidity in a predominantly pediatric Caucasian population. Patients with severe and chronic uveitis may experience significant uveitis-related complications and subsequent visual loss despite aggressive treatment.

To present two pediatric cases where multifocal electroretinogram (mfERG) was able to establish an earlier diagnosis compared to full field electroretinogram (ERG) Case 1: an 11-year-old boy with reduced visual acuity, pale discs, macular pigmentation with white dots bilaterally. Case 2: a 12-year-old girl with reduced vision in her right eye, slight pallor of the right optic disc, intense pigmentation at both maculae and scattered punctate lesions throughout the peripheral fundi. Both had been investigated with electrodiagnostic tests according to the International Society of Clinical Electrophysiology for Vision protocol. Full-field ERGs for both children showed normal responses. Case 1: mfERG revealed a severe reduction in function in the inner 20°. Case 2: mfERG showed attenuated responses in each eye. Clinical examination and mfERG were consistent with Stargardt disease. mfERG is applicable to children and is a sensitive tool for early diagnosis of retinal dystrophies.

Purpose To report successful treatment of a rare case of sight-threatening pediatric multifocal choroiditis with panuveitis (MFCPU) and the use of electrophysiology to confirm return of macular function. Methods Case report. Results An 8-year-old boy with a history of bilateral recurrent non-juvenile idiopathic arthritis acute anterior uveitis (AAU) presented with new-onset blurry vision and floaters in both eyes. Visual acuity had deteriorated to 20/200 right eye and 20/100 left eye. Cells were observed in the anterior chamber and vitreous of both eyes. Ophthalmoscopy showed multiple active small cream-colored chorioretinal lesions and cystoid macular edema (CME) in both eyes in the absence of systemic disease, suggestive of idiopathic MFCPU. Successful rapid visual recovery and resolution of CME confirmed by spectral-domain optical coherence tomography (SD-OCT) was achieved with prompt intensive systemic steroid therapy followed by early introduction of methotrexate. After 9 months, his visual acuities improved to 20/32, and pattern reversal visual evoked potentials and 19 hexagon multifocal electroretinography posttreatment were normal, showing recovery of macular function. Conclusions Multifocal choroiditis with panuveitis is rare in children and has not been documented in the presence of previous longstanding recurrent AAU. Onset of floaters in children should alert the clinician to early stages of posterior pole involvement and progression to reduction in vision due to CME requires prompt aggressive steroid therapy monitored by clinical examination, SD-OCT, and electrophysiology, followed by early introduction of immunosuppressive drugs for long-term stability and to avoid steroid-induced adverse effects in children.

A squint, also known as strabismus, is a condition where the eyes are misaligned because of incorrect balance in the controlling eye muscles. This may result from muscular, neuromuscular or purely mechanical factors. An affected eye will have either predominating vertical or horizontal deviation. Vertical deviations are usually classified into eight classes (diagnoses) and horizontal into 10. The present work considers only the former but extension to the latter is straightforward.The differential diagnosis of strabismus is usually achieved in the prism cover test (PCT). A range of test prisms is presented to the eye and the resulting deviation in a particular direction of gaze is observed. In the full PCT, 10 positions of gaze are considered: in each position there are, say, 40 prisms of plus and minus power to investigate. The problem can be expressed as the inference 1-of-8 diagnoses in the output space from an input space of 10 parameters each with a resolution of 1-in-80. However, in the majority of clinical examinations, the corner-most positions of gaze are difficult to assess, particularly in children. Therefore, frequently the 6-position subset is reported requiring a corresponding reduction in the input space dimensions of 10 to 6. Web-StrabNet©is an expert system for the differential diagnosis of strabismus based on parallel instances of multi-layer perceptrons trained on exemplar data generated in consensus by two clinical experts. This machine expert is programmed in MatLab™ and is freely available as an Internet website (www.strabnet.com) which uses MatSOAP©, an XML/SOAP accessible automation server running a number of simultaneous MatLab instances.StrabNet achieves diagnostic accuracies of 100 and >94% with artificial data and typically ∼99 and ∼99% in clinical data-sets for the 10-position and 6-position subset PCT's, respectively.

Registering a child as visually impaired is a potentially traumatic, but necessary, milestone in paediatric ophthalmology. Registration enables the provision of services essential to maximise the child's potential. This study was carried out to investigate the changes over a 10-year period in the rates of registration of childhood blindness at a tertiary paediatric ophthalmology department. Particular attention was given to diagnosis, whether the disease was preventable, time to registration, age at registration, and the socioeconomic status of the patient's family. A retrospective analysis of all children registered blind or partially sighted over a 10-year period until December 2006. A total of 256 children were registered blind or partially sighted over the 10 years. All cases were analysed. Of these, 58.2% were male and the average age at registration was 76 months; 52.0% were registered as severely sight-impaired. The most common primary diagnosis was cerebral visual impairment (CVI) in 27% cases, followed by optic atrophy in 16%, and the commonest anatomical site involved was the retina in 30.9%. An average of 25.6 (SD 8.0) registrations were carried out each year. The number of registrations per year is increasing. Seven cases (2.7%) were deemed avoidable and 61 cases (23.8%) were deemed potentially treatable. The mean index of multiple deprivation (IMD) score for the English cases (45.1) was significantly higher than of the surrounding area (P

Consecutive exotropia is commonly the result of a surgical correction of a primary esotropia but may develop spontaneously. This study examines the clinical characteristics of patients who have developed a spontaneous consecutive exotropia and relates the key features to previously reported findings.Patients were identified by routine clinical practice from May 2000 to December 2003 by retrospective case note analysis. Patients that presented with an esotropia that became an exotropia (without surgery or botulinum toxin A) were included.This study consisted of 14 patients who presented with an esotropia from early weeks of life to almost 4 years. No patients were undergoing occlusion treatment at the onset of the exotropia and no subject had dense amblyopia. The most common characteristics included (1) age of onset of esotropia of 24 months or less; (2) hypermetropic refractive error of +5 DS mean spherical equivalent; (3) lack of binocular single vision.The results highlight the variability of the condition with no single consistent finding, with the lack of binocular single vision, early onset esotropia, and high hypermetropia being common findings. Amblyopia was not found to be an important characteristic.

Strabismus is a condition in which the eyes are not properly aligned with each other. Different treatment options are available to treat strabismus. Surgery is considered to be the cornerstone of strabismus management when all else fails. However treatment with botulinum toxin has been seen to produce good results in the short also with one study showing better results than one surgical series and atleast similar results to the other published surgical series. As the surgical intervention is a more invasive procedure, if the same effect can be achieved by the botox injection, it provides an attractive option to patients. Our research aims to probe into this better alternative and thus looking at the long term effect of botulinum toxin on patients who have binocularity potential versus those who had no binocularity.

Mitochondrial disorders are associated with well recognized ocular manifestations. Pearson syndrome is an often fatal, multisystem, mitochondrial disorder that causes variable bone marrow, hepatic, renal and pancreatic exocrine dysfunction. Phenotypic progression of ocular disease in a 12-year-old male with Pearson syndrome is described. This case illustrates phenotypic drift from Pearson syndrome to Kearns-Sayre syndrome given the patient's longevity. Persistent corneal endothelial failure was noted in addition to ptosis, chronic external ophthalmoplegia and mid-peripheral pigmentary retinopathy. We propose that corneal edema resulting from corneal endothelial metabolic pump failure occurs within a spectrum of mitochondrial disorders.

To demonstrate the use of the multifocal electroretinogram (mfERG) in addition to the full-field electroretinogram (ERG) in defining varying clinical pictures in children within a family with Bardet-Biedl syndrome (BBS).All members from a family generation underwent a detailed history and examination before proceeding to a detailed ERG in accordance with the International Society of Clinical Electrophysiology for Vision protocol and a rapid, low-resolution mfERG. Of the sibling pair, the 13-year-old boy showed reduced vision and atypical maculopathy and the 10-year-old sister showed normal vision and atrophic maculopathy. Parents had normal ocular examination.The male sibling had reduced rod and cone full-field ERG responses with a relatively spared central response from the mfERG suggesting central macular sparing. In contrast, for the female sibling, the ERG was normal for the cone pathway although reduced for rod pathway, with mfERG showing central involvement. The mother had rod responses at the lower end of normal range, a normal cone pathway, and a normal mfERG. The father showed a normal ERG and mfERG.The mfERG is a useful adjunct to full-field ERG in the paediatric population and in family studies.

Human observers are able to locate contours that are defined solely on the basis of long-range, orientation-domain correlations. The integrity of the mechanisms responsible for second-order contour detection is disrupted by amblyopia (Kovacs et al., 1996; Hess et al., 1997) and it is therefore of interest to develop methods for assessing pediatric patients undergoing treatment for amblyopia. In this study, we have determined the inter-observer and test-retest reliability of a card-based test of second-order contour integration. The magnitude of practice effects was also assessed in both adult and pediatric patient groups. Contour detection thresholds were measured for a closed contour, defined by Gabor patches, embedded in a randomly oriented Gabor-patch background. The visibility of the contour was controlled by varying the density of the background elements. Thresholds, defined in terms of the ratio of contour element spacing to average background spacing were measured with a clinical staircase procedure. Thresholds measured by two observers differed on average by 0.023 +/- 0.075 or about one half the increment between cards. Children and adults showed only small practice effects (0.022 +/- 0.051 vs 0.053 +/- 0.077, respectively) and average unsigned differences between repeated measures were equivalent to approximately 1 card across groups. A card-based test of second-order contour integration produces reliable estimates of contour integration performance in normal and amblyopic observers, including children.

To evaluate the Nidek handheld automated keratometer and compare it with the manual Zeiss keratometer.St. Paul's Eye Unit, Royal Liverpool University Hospital, Liverpool, United Kingdom.Forty-five normal adult volunteers were included in the study. Three sets of randomized keratometry measurements were taken from both eyes of each adult, with both instruments by two independent observers. Readings included powers of the steep and flat meridians and axis of the flat meridian. The mean difference between the two instruments was calculated. The variance of each instrument was calculated for the axis, the steep and flat meridians, and the mean of the two meridians.There was no significant difference between the mean Nidek and Zeiss keratometry readings for the steep (0.015 mm; P = .167) or flat (0.054 mm; P = .069) meridian or axis measurements (P = .172). On repeated measurements, the within-subject and within-group variabilities, calculated separately for each instrument, were significantly less for the Nidek automated keratometer than the Zeiss keratometer (P.01) when measuring the steep and flat meridians. There was however, a significant increase in axis variability using the Nidek keratometer (range 20 degrees; P.01).The Nidek automated keratometer was accurate, reliable, and easy to use and compared favorably with the manual Zeiss keratometer when measuring corneal curvature. In the handheld mode, the Nidek is not suitable for axis measurements. It has the additional advantage of portability.

We describe the association of auricular abnormalities and cleft lip with or without cleft palate in two siblings. One sibling has postauricular pits, profound myopia, nystagmus and retinal pigment abnormalities. The second sibling was a fetus of 23 weeks gestation with severe cleft lip, cleft palate and external ear abnormalities. As this constellation of features has not been described together before, we believe this is a new syndrome.

Case report of a 16-year-old boy presenting with total hyphema due to blunt trauma to the left eye. During a subsequent cinematic MRI scan to identify salvageable lateral rectus muscle, the attachment of the left lateral rectus was obscured by a 20-mm diameter signal void. A subsequent CT scan for a suspected metallic foreign body revealed the muscle attachment after all. The theoretical explanations for this finding are discussed

We report our results with systemic Etanercept in patients with juvenile idiopathic arthritis in a joint ophthalmology-rheumatology clinic at a tertiary hospital.Patients with JIA on Etanercept were identified from a dedicated uveitis database. A retrospective review of electronic and paper-based patient records was performed.Nine patients with JIA and current or previous treatment with Etanercept were identified, including six females and three males. Five patients with previous or current uveitis were noted. A further four were under observation for uveitis and required Etanercept for their joint disease. All nine patients had previously been taking Methotrexate, which had a suboptimal response in controlling arthritis or uveitis. Six out of nine patients did not show any uveitis activity at their last follow-up. Eyes of three patients still show signs of active inflammation in the anterior chamber (two on Etanercept and one off Etanercept). Severely impaired visual acuity (PL) was recorded in both eyes of one patient with long-standing persistent uveitis. Moderate visual loss in one eye of one patient was seen. The remaining seven patients did not show any significant loss of vision. Intraocular inflammation was not induced in any patient started on Etanercept.Etanercept may be useful in controlling JIA-related uveitis or arthritis in a pediatric patient when Methotrexate has had a suboptimal response in controlling the inflammatory activity.

Peribulbar anaesthetic blocks were administered to 70 patients and the intraocular pressure (IOP) measured immediately before and within 1 minute of the injections. In 10 patients IOPs were recorded at 1 minute intervals for 15 minutes after injection and then compared with the IOPs recorded in 60 patients after 5 or 10 minutes of Honan balloon ocular compression. The IOP rose significantly after injection in all patient groups and in some cases this increase was marked (over 50 mm Hg in 10 patients). The IOP showed an equivalent drop after 5 or 10 minutes of ocular compression when compared with eyes that did not receive ocular compression. The Honan balloon does not appear to be necessary to reduce IOP in the 10 minutes following peribulbar injection. Furthermore, the occurrence of IOP peaks after peribulbar anaesthesia suggests that the balloon should be used with caution in eyes in which the ocular circulation may be compromised.

We describe a report of a child with a horner’s syndrome and sixth nerve paresis secondary to a petrous internal carotid artery (ICA) aneurysm. Management of this condition involved coiling of the aneurysm and the use of botulinum toxin to manage his strabismus and associated symptoms.

Our goal is to develop an accessible expert system (StrabNet) that will assist in the clinical diagnosis of vertical strabismus, form the basis of a teaching/learning tool, and contribute to the audit process. Potentially, this model can be extended to other strabismus deviations.Vertical deviations were separated into eight classifications (diagnoses). An expert system based on architecture of artificial neural networks learned the patterns for each class of deviation based on 10 prism cover-test measurements (9 cardinal positions and near fixation). The expert system was tested with previously unseen and real-patient data. This system was extended to a reduced model requiring only six measurements (primary position, right, left, up, down gaze, and near fixation), and evaluated with real patient data. A freely available Web implementation is available on the Internet at www.StrabNet.com .The expert system was found to be highly accurate at diagnosing vertical strabismus (100% and approximately 96% for ten and six measurement models, respectively) from one of the eight classes.StrabNet is of demonstrable value in diagnosing commonly presenting vertical deviations from prism cover test (PCT) measurements. Its potential role in teaching and in audit is identified.

A selective review of the contemporary understanding of development of infant visual acuity is presented together with recent developments in methodology to detect this change. References are confined, wherever possible, to human infant studies relating to factors explaining the development of acuity. Results obtained from a two year study of the development of grating acuity in normal infants are discussed briefly. The findings indicate the importance of establishing acuity norms and sensitivity of interocular acuity difference as an important parameter in the detection of monocular visual deficit in clinical practice.

We describe the phenotype of a male infant with an interstitial deletion of the short arm of chromosome 8 (p. 11.2–p. 21). Visual impairment is a major feature in this case. The clinical, radiographic and electrodiagnostic findings are presented. Only four other cases have been reported in which visual problems are associated with a deletion of 8 p.

Purpose: We report a case series of seven patients who presented with strabismus and no apparent known neurological deficit. Methods: A retrospective review of notes was performed on all patients presenting at the Royal Liverpool Children's Hospital (Alder Hey) with strabismus, in whom subsequent investigation revealed the presence of periventricular leukomalacia (PVL). Results: All seven patients presented with esotropia. One patient also had dissociated vertical deviation. A history of premature birth was elicited in six cases; however, one patient had been born at 42 weeks. Apparently uncomplicated routine surgery produced unexpectedly poor results. Conclusions: Patients with undiagnosed PVL may present to the ophthalmologist with strabismus and no other apparent neurological abnormality. Where it is suspected that the patient may have suffered a significant hypoxic-ischaemic event, the ophthalmologist should have a low threshold for investigating with magnetic resonance imaging, particularly if the patient shows unexpected outcomes following appropriate treatment. Patients and parents should be counselled on possible suboptimal results prior to the offer of surgical correction of strabismus.

An expert system is described for the differential diagnosis of vertical deviation strabismus (squint) from measurements taken in the standard prism cover test. The deviations are represented as optical powers in prism dioptres using the graphic representation of strabismus (after Jampolsky). The expert is implemented in MatLab® (Mathworks Ltd., Cambridge, UK) both as a stand-alone program on a PC and as a web application available over the Internet (see http://www.strabnet.com). In trial and clinical datasets a diagnostic accuracy of 100% was achieved.

PURPOSE. The main purpose of this work was to measure repeatability of line-by-line logMAR (logarithm of the minimum angle of resolution) acuity in normal and amblyopic children, while adequately controlling for optical defocus. METHODS. The Lea Symbols Chart is a constant-crowding, equallogMAR increment chart similar in design to the Early Treatment Diabetes Retinopathy Study [ETDRS] chart. LogMAR visual acuity was tested twice in each eye of 32 amblyopic and 11 normal children. Each test commenced with screening in which one of the three central symbols was chosen for identification starting with the 1.0- or 0.9-logMAR line, progressing to every second line until incorrect identification occurred. Symbol-by-symbol presentation then commenced at the logMAR line containing the last correctly identified symbol. The threshold was recorded as the last logMAR line where four of four or four of five correct responses occurred (i.e., line-by-line scoring). Retesting by the same examiner was identical and occurred within the same session. RESULTS. There was no significant difference in repeatability among normal, fellow, or amblyopic eyes. The difference between test and retest thresholds lay between 0.10 logMAR in 93% of eyes. The 95% limits of agreement for the difference was 0.18 logMAR. Repeatability in eyes tested first did not differ from that in those tested second in either the normal or amblyopic groups. CONCLUSIONS. In the age-group tested, the line-by-line method of threshold scoring compares favorably with previous reports of both line-by-line and interpolated threshold scoring. There was no clinically meaningful difference in repeatability between the normal and amblyopic children tested. (Invest Ophthalmol

PURPOSE. An objective measure of positional acuity is desirable in the nonverbal clinical population. This study was conducted to investigate the specificity of the vernier VEP as a measure of positional acuity, evaluating the potential confound of asymmetric motion responses that may be present in some groups of patients. These motion responses could masquerade as position-specific responses, since they occur at the same response frequency as the vernier-related response. METHODS. Twelve observers with early-onset esotropia (EOE), 30 children with untreated amblyopia, and 15 control children underwent swept vernier VEP acuity testing accompanied by a swept motion control stimulus. The control condition was used to detect the presence of artifactual responses not related to position sensitivity. The patients with EOE were selected for high levels of motion asymmetry as documented with oscillating gratings presented monocularly. As a measure of motion confound (penetration), the proportion of first-harmonic responses recorded in the control condition was determined. RESULTS. The penetration rate in the vernier condition in each study group (EOE: 0.93%; amblyopes: 4.26%; normal subjects: 2.40%) and the entire group (2.85%) was acceptably low. The level of penetration was not significantly influenced by the presence of amblyopia. CONCLUSIONS. The vernier VEP paradigm, when applied in the manner described, can be interpreted as a measure of position sensitivity. The presence of motion asymmetry or untreated amblyopia does not affect the validity of vernier measurements made. (Invest Ophthalmol Vis Sci. 2005;46:4563‐4570) DOI: 10.1167/iovs.05-0792

The molecular characterization of a UK family with an autosomal dominant congenital cataract associated with microcornea is reported.Family history and clinical data were recorded. This phenotype was linked to a 7.6 cM region of chromosome 22q11.2-q12.2, spanning the beta-crystallin gene cluster (ZMax of 3.91 for marker D22S1114 at theta=0). Candidate genes were PCR amplified and screened for mutations on both strands using direct sequencing.Sequencing of the coding regions and flanking intronic sequences of CRYBB2 and CRYBB1 showed the presence of a novel, heterozygous X253R change in exon 6 of CRYBB1. SSCP analysis confirmed that this sequence change segregated with the disease phenotype in all available family members and was not found in 109 ethnically matched controls.X253R is predicted to elongate the COOH-terminal extension of the protein and would be expected to disrupt beta-crystallin interactions. This is the first documented involvement of CRYBB1 in ocular development beyond cataractogenesis.

PURPOSE. In several studies, researchers have found that integration of orientation information along contours defined by Gabor patches is abnormal in patients with strabismus and in untreated patients with anisometropic amblyopia. In this study, the rate and degree of recovery of contour-integration deficits were compared with the recovery of logMAR (logarithm of the minimum angle of resolution) visual acuity deficits in patients newly diagnosed with amblyopia secondary to anisometropia, strabismus, or both. METHOD. Contour-detection thresholds and optotype acuity were measured in 17 newly diagnosed anisometropic amblyopes, in 6 patients with strabismic amblyopia, and in 4 patients with combined anisometropic and strabismic amblyopia. Contour-detection thresholds were measured with a cardbased procedure. Treatment comprised full refractive correction and full-time total occlusion therapy, when necessary. Visual function was measured at monthly visits during the course of treatment, with an average follow-up period of 16 weeks (12‐24 weeks) for the entire group. Complete data were obtained from 23 patients through 8 weeks of follow-up. RESULTS. Significant interocular differences in contour-detection thresholds were present in 16 of the 27 patients at the first visit after initial refractive correction. Interocular differences in contour-detection thresholds declined to normal levels in most of the patients within 8 weeks of the initiation of treatment. Interocular acuity differences remained significant in many of the patients (19/23) at 8 weeks of follow-up and continued to decline, but did not fully normalize, over the remainder of the follow-up period. CONCLUSIONS. Refractive correction alone or in combination with occlusion therapy produces a normalization of contourintegration thresholds in amblyopia that is more rapid and complete than that achieved for visual acuity. (Invest Ophthalmol Vis Sci. 2004;45:4016‐4022) DOI:10.1167/iovs.03-0795

Although orbital cellulitis is the most common cause of acute-onset proptosis with inflammatory signs in a child, the clinician should always be alert to the possibility of rhabdomyosarcoma. We describe an unusual presentation of acute-onset nonaxial proptosis of the left orbit without sinus disease or systemic toxicity in a 6-year-old boy. Our clinical differential diagnosis included orbital cellulitis, metastatic disease, capillary haemangioma, lymphangioma with cyst, ruptured dermoid cyst, and orbital rhabdomyosarcoma. Only after orbital biopsy and subsequent microbiologic confirmation were obtained was a diagnosis of chronic orbital abscess tenable. Features in our patient included paucity of symptoms and signs of inflammation. This case illustrates the difficulty in differentiating a chronic orbital infection from orbital rhabdomyosarcoma on the basis of clinical, laboratory, and orbital imaging findings. Possible causes of this unusual presentation are discussed.

Previous studies have suggested that the integration of orientation information across space is impaired in amblyopia. We developed a method for quantifying orientation-domain processing using a test format that is suitable for clinical application. The test comprises a graded series of cards where each card includes a closed path (contour) of high contrast Gabor signals embedded in a random background of Gabor signals. Contour visibility in both normals and patients with histories of abnormal binocular vision depends jointly on the spacing of elements on the contour as well as background element density. Strabismic amblyopes show significant degradation of performance compared to normals. Small but significant losses in sensitivity were also observed in a group of non-amblyopic strabismus patients. Threshold measurements made with contrast reducing diffusers indicated that the amblyopic loss is not due to the reduced contrast sensitivity of the amblyopic eye. An abnormal pattern of long-range connectivity between spatial filters or a loss of such connectivity appears to be the primary source of contour integration deficits in amblyopia and strabismus.

Background: A prospective study was undertaken to compare the binocular fixation pattern and presence of amblyopia in strabismic children. Methods: Fifty-three children with manifest strabismus and the ability to cooperate with an optotype acuity test were examined. The binocular fixation pattern and logMAR visual acuity were recorded by separate, masked observers under standardized conditions. The binocular fixation pattern was divided into four grades from alternation to uniocular fixation. Results: Patients who freely alternated did not have amblyopia, while those who maintained or preferred fixation with a given eye tended to have amblyopia in the nonpreferred eye. Conclusion: The binocular fixation pattern can be rapidly assessed with minimal equipment and training. These findings confirm the usefulness of a graded assessment of the binocular fixation pattern in the detection of amblyopia. Journal of Pediatrie Ophthalmology and Strabismus 2000;37:24-28.

Patients with early disruptions of binocularity show cortical directional asymmetries in their steady state monocular VEP response to oscillatory motion. The VEP directional asymmetry is characterized by significant first harmonic components that show a 180° difference in the response phase between the two eyes. By contrast, the normal response is dominated by even-order response harmonics, although some normal observers also have measurable responses at the first harmonic. Experiments and simulations were conducted to determine if the first harmonic in patients could reasonably be attributed to direction selective mechanisms. A secondary goal was to determine whether the first harmonic response of normals was also due to imbalances in direction selective mechanisms. Monocular steady state VEPs were elicited by oscillating 3 c/deg gratings presented at 6 and 10 Hz in normal observers and observers with infantile esotropia. Responses were also obtained to phase-reversing gratings of the same spatial and temporal frequencies. Phase reversal eliminated the majority of first harmonic responses which were recorded for normal observers to oscillatory motion. However, phase reversal did not elicit the cortical motion asymmetry in infantile esotropia. Modeling results suggest that the first harmonic response to oscillatory motion arises due to non-linearities in both direction selective and non-direction-selective mechanisms, with the latter being dominant in patients with early onset strabismus.