Individualised variable-interval risk-based screening for sight-threatening diabetic retinopathy: the Liverpool Risk Calculation Engine.

Aims/hypothesis: Individualised variable-interval risk-based screening offers better targeting and improved cost-effectiveness in screening for diabetic retinopathy. We developed a generalisable risk calculation engine (RCE) to assign personalised intervals linked to local population characteristics, and explored differences in assignment compared with current practice.

Methods: Data from 5 years of photographic screening and primary care for people with diabetes, screen negative at the first of > 1 episode, were combined in a purpose-built near-real-time warehouse.

Predictive value of N95 waveforms of pattern electroretinograms (PERGs) in children with optic nerve hypoplasia (ONH).

Purpose: As part of a long-term, prospective study of prenatal and clinical risk factors for optic nerve hypoplasia (ONH) at Children's Hospital Los Angeles, pattern ERGs (PERGs) were evaluated for prognostic value using an automated objective and robust analytical method.

Methods: Participants were 33 children with ophthalmoscopically diagnosed ONH [disc diameter-to-disc macula ratio (DD/DM) less than 0.35 in one or both eyes on fundus photographs].

Temporary sympathectomy in chronic refractory angina: a randomised, double-blind, placebo-controlled trial.

Background: Temporary sympathectomy by injection of bupivacaine at the site of the left stellate ganglion is used in the management of refractory angina at several UK centres. Although patients frequently report significant reduction in symptoms, efficacy has not been established by double-blind, randomised placebo-controlled trial (RCT).

Objective: To investigate the efficacy of the procedure for the first time by a double-blind RCT.

Comparison of human expert and computer-automated systems using magnitude-squared coherence (MSC) and bootstrap distribution statistics for the interpretation of pattern electroretinograms (PERGs) in infants with optic nerve hypoplasia (ONH).

Purpose: Pattern electroretinograms (PERGs) have inherently low signal-to-noise ratios and can be difficult to detect when degraded by pathology or noise. We compare an objective system for automated PERG analysis with expert human interpretation in children with optic nerve hypoplasia (ONH) with PERGs ranging from clear to undetectable.

Methods: PERGs were recorded uniocularly with chloral hydrate sedation in children with ONH (aged 3.

Cluster analysis of multiplex ligation-dependent probe amplification data in choroidal melanoma.

Purpose: To determine underlying correlations in multiplex ligation-dependent probe amplification (MLPA) data and their significance regarding survival following treatment of choroidal melanoma (CM).

Methods: MLPA data were available for 31 loci across four chromosomes (1p, 3, 6, and 8) in tumor material obtained from 602 patients with CM treated at the Liverpool Ocular Oncology Center (LOOC) between 1993 and 2012. Data representing chromosomes 3 and 8q were analyzed in depth since their association with CM patient survival is well-known.

Shoulder muscle activation and coordination in patients with a massive rotator cuff tear: an electromyographic study.

Adaptive muscle activation strategies following a massive rotator cuff tear (MRCT) are inadequately understood, and the relationship among muscles during everyday activities has not been considered. Thirteen healthy subjects comprised the control group, and 11 subjects with a MRCT the patient group. Upper limb function was assessed using the Functional Impairment test-hand, neck, shoulder, and arm (FIT-HaNSA).

Investigation of the temporal properties of the retina using the m-sequence.

The mfERG provides a topographic map of function of the retina and has been used in numerous studies to identify macular, paramacular and peripheral retinal dysfunction. This study investigates the changes in response due to the presentation rate of the stimulus. Twenty subjects gave informed consent to take part in the study, which had local regional ethical committee approval.

Normal shoulder muscular activation and co-ordination during a shoulder elevation task based on activities of daily living: an electromyographic study.

Studies of normal shoulder function have often failed to consider the inter-relationship between different muscle groups in activities relevant to daily life. Upper limb functional status was assessed in 12 healthy male volunteers using the Functional Impairment Test-Hand, Neck, Shoulder and Arm test (FIT-HaNSA). Electromyography was then used to study the activity and coordination of 13 muscles (10 by surface electrodes, 3 by fine-wire intramuscular electrodes) around the shoulder during a dynamic movement task based on the shelf-lifting task in FIT-HaNSA.

Changing characteristics and mode of death associated with chronic heart failure caused by left ventricular systolic dysfunction: a study across therapeutic eras.

Background: Therapies for patients with chronic heart failure caused by left ventricular systolic dysfunction have advanced substantially over recent decades. The cumulative effect of these therapies on mortality, mode of death, symptoms, and clinical characteristics has yet to be defined.

Methods And Results: This study was a comparison of 2 prospective cohort studies of outpatients with chronic heart failure caused by left ventricular systolic dysfunction performed between 1993 and 1995 (historic cohort: n=281) and 2006 and 2009 (contemporary cohort: n=357).

A clinical alternative to fluorophotometry for measuring tear production in the diagnosis of dry eye.

Purpose: To determine the utility of the tear function index (Liverpool modification TFI) in assessing tear turnover rate (TTR), evaluate association of tear clearance rate (TCR) and TFI with measurements of TTR by fluorophotometry, and determine effectivity of these test measures in dry eye (DE) diagnosis.

Methods: Forty-one subjects with DE and 15 control subjects participated. Tests included symptoms, fluorophotometry (by automated scanning fluorophotometry), and TCR and TFI from a prepared Liverpool modification TFI strip.

Pattern recognition of vertical strabismus using an artificial neural network (StrabNet).

Background: 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.

Methods: Vertical deviations were separated into eight classifications (diagnoses).

The behaviour of knots and sutures during the first 12 hours following a Bankart repair.

It has been reported that the effectiveness of arthroscopic procedures in terms of preventing recurrent dislocation has not matched that from open techniques. Also little is known about how these knots behave when exposed to physiological loading following repair. This study presents the development of a practical tool to allow surgeons to test the quality of their arthroscopic knots and allow them to make choices with regard to knot configuration and suture material.

A web-based tool for the assessment of discrimination and calibration properties of prognostic models.

Prognostic models are developed to assist clinicians in making decisions regarding treatment and follow-up management. The accuracy of these models is often assessed either in terms of their discrimination performance or calibration but rarely both. In this paper, we describe the development of an online tool for discrimination using Harrell C index and calibration using a Hosmer-Lemeshow type analysis (http://clinengnhs.

Assessment of functional recovery in tennis elbow.

Objectives: (a) To investigate changes in muscular strength, fatigue and activity in recovered tennis elbow (RTE); (b) to assess the appropriateness of EMG and strength measurements in monitoring functional recovery in tennis elbow (TE).

Methods: Study included three age-matched female groups of Control (C) (n=8, no history of musculoskeletal problems), TE (n=7, local tenderness at the lateral epicondyle and pain with resisted wrist and middle finger extension) and RTE (n=6, asymptomatic for at least 6 months, no lateral epicondyle tenderness). Measurements included metacarpophalangeal (MCP), wrist, shoulder and grip isometric strength and EMG measures of muscle fatigue and activity for five forearm muscles (wrist extensors and flexors).

Artificial neural networks estimating survival probability after treatment of choroidal melanoma.

Purpose: To describe neural networks predicting survival from choroidal melanoma (i.e., any uveal melanoma involving choroid) and to demonstrate the value of entering age, sex, clinical stage, cytogenetic type, and histologic grade into the predictive model.

Heat treatment of arthroscopic knots and its effect on knot security.

Purpose: The purpose of this study was to investigate heat application to arthroscopic knots as a method of improving knot security.

Methods: Heat treatment was assessed on 4 suture materials--Ethibond (Ethicon, Somerville, NJ), PDS (Ethicon), Orthocord (DePuy Mitek, Raynham, MA), and FiberWire (Arthrex, Naples, FL)--tied by use of the Duncan loop, compared with untreated controls. A hand-tied surgeon's knot with Ethibond was included as the gold standard.

Deficits in the electroretinogram in neovascular age-related macular degeneration and changes during photodynamic therapy.

Purpose: To describe the deficits in four electroretinography (ERG) modalities in patients with neovascular age-related macular degeneration (AMD). To describe the changes in these parameters during a course of verteporfin photodynamic therapy (PDT).

Methods: Pattern (PERG), multifocal (mfERG) (19 segment simplified test protocol), flash ERG and flicker ERG were performed in patients with active neovascular AMD before PDT and compared to fellow eye controls using paired t-tests.

The differential diagnosis of vertical strabismus from prism cover test data using an artificially intelligent expert system.

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.

Upper limb muscle imbalance in tennis elbow: a functional and electromyographic assessment.

The purpose of this study was to investigate strength, fatigability, and activity of upper limb musculature to elucidate the role of muscular imbalance in the pathophysiology of tennis elbow. Sixteen patients clinically diagnosed with tennis elbow, recruited from a university hospital upper limb orthopedic clinic, were compared with 16 control subjects with no history of upper limb musculoskeletal problem, recruited from university students and staff. Muscle strength was measured for grip, metacarpophalangeal, wrist, and shoulder on both sides.

Pain, functional disability, and psychologic status in tennis elbow.

Objectives: First to compare pain and functional disability in tennis elbow (TE) patients with healthy controls. Second, to evaluate the relationship between the 2 major psychologic factors (anxiety and depression) and TE.

Methods: Sixteen TE patients were recruited from 46 consecutive attendees at an upper limb clinic: inclusion criteria were lateral epicondyle tenderness, pain with resisted wrist and middle finger extension and at least 3 months localized lateral elbow pain.

Automatic positioning of cursors in the transient pattern electroretinogram (PERG) with very poor SNR using an Expert System.

An expert system is described which automatically cursors PERG waveforms of very poor signal-to-noise ratio. The training data-set is derived from shape-perturbated PERG waveforms based on the ISCEV Standard and a series of clinically-normal waveforms. In validation trials, the Expert System is clearly shown to out-perform the Human Expert in the presence of noise.

Terrien marginal degeneration presenting with spontaneous corneal perforation.

Purpose: To report spontaneous corneal perforation as a presenting sign of unilateral Terrien marginal degeneration in a young adult.

Methods: A 19-year-old woman presented with sudden loss of vision in her left eye of 1-day duration. Examination revealed superior corneal thinning with superficial vascularization and secondary lipid keratopathy.

Corneal topographic features in a family with nanophthalmos.

Purpose: To characterize the corneal topographic features in a family with nanophthalmos.

Methods: Two observational case reports and a review of the literature. Corneal shape was analyzed using a topographic modeling system (TMS) and an Orbscan topographic system, with further analysis based on Fourier series and Zernicke polynomials.

Examination of short binary sequences for mfERG recording.

The mfERG, when first introduced by Erich Sutter used long sequences with short periods (approximately 15 ms) between steps (flashes). Since then a number of studies have introduced slower or modified sequences to emphasise Oscillatory Potentials (OPs), Optic Nerve Head Components (ONHC) or the s-wave. With this reduction in the rate of presentation many of the investigators have reduced the length of the sequence to allow a shorter recording period.

Congenital absence of optic chiasm: demonstration of an uncrossed visual pathway using monocular flash visual evoked potentials.

A 35 month old child was referred for electrophysiology testing with pendular nystagmus, corresponding head oscillations and reduced vision. Flash visual evoked potential (VEP) revealed large responses at the right occiput (but not the left occiput) from the right eye and similar large responses at only the left occiput from the left eye, indicating absent/deficient crossover at the chiasm. A magnetic resonance imaging (MRI) scan subsequently confirmed absence of the optic chiasm.