Bronchopulmonary dysplasia and oxidative stress: are we closer to an understanding of the pathogenesis of BPD?

In recent years a body of data has accumulated, linking the development of bronchopulmonary dysplasia (BPD) to increased oxidative stress in the first few days after birth, since high concentrations of metabolites reflecting increased peroxidation products such as pentane, ethane, protein carbonyl, o -tyrosine, allantoin and F₂-isoprostanes, as well as low levels of glutathione and sulfhydryl/total protein ratio, also reflecting increased oxidative load, have been found in the premature infants at risk of or developing BPD. Oxidative stress seems to increase lung antioxidants in some experimental models of BPD and hyperoxia affects foetal lung growth. There are similarities between inflammation and hypoxia/reoxygenation, since both activate a number of inflammatory mediators such as cytokines and adhesion molecules, some of which are found in high concentrations in tracheal aspirate fluid of infants developing BPD. Surfactant production and function are also altered by both hyperoxia and reactive oxygen species per se , making the lungs more vulnerable to injury. This new knowledge may result in new and more efficient therapeutic approaches, hopefully leading to the eradication of BPD in the near future.     

Visual function before and after ACTH therapy for vision loss in multiple sclerosis

The visual function of a patient with multiple sclerosis (MS) was evaluated by visually evoked cortical potentials (VEPs) and the contrast sensitivity function (CSF) before and after adrenal corticotrophic hormone (ACTH) therapy for an acute exacerbation of the condition. Although Snellen visual acuity returned to normal in each eye, steady-state pattern reversal VEP waveforms remained degraded long after therapy and monocular CSFs were reduced unequally 18 days after therapy, and even three years later. On the other hand, flash VEPs, recorded within three weeks of ACTH therapy, showed an improvement that parallelled the patient's overall improvement which appeared to be associated with the ACTH therapy. These observations indicate that MS can affect spatial and temporal channels differentially, reinforce the previously reported clinical utility of VEPs for the diagnosis of MS, and suggest that they may be simple, clinically useful, objective indices of the effectiveness of any interventive medical management of the disease.     

Spectacle fitting with ear,nose and face deformities or abnormalities

Spectacle frame selection and dispensing remain significant components of optometry. Occasionally, we encounter patients who are unable to wear conventional spectacles due to abnormalities or deformities following injury and/or surgery to their nose, ears or head. In these cases, spectacle frame fitting may be more complex and customised frame adjustments may be required to account for the anatomical variations. A patient with a microtia (hypoplastic pinna) was fitted with a tailored spectacle frame. The details are presented together with a summary of different frames and modifications available for ears, nose and face abnormalities.     

Post-stroke visual midline shift syndrome

The state of research on the topic of visual midline shift syndrome following a cerebrovascular accident is unknown. A scoping review was conducted using the search terms of ‘visual midline shift’ (or equivalent) and ‘cerebrovascular accident’ (or equivalent). Articles were selected from eight academic and one grey literature database, and went through two levels of review, as per Arksey and O'Malley, before being deemed acceptable for inclusion. Of the 931 abstracts reviewed, 27 articles met the criteria for inclusion. Data extracted from the selected articles included terminology and definition, symptoms, underlying pathophysiology, duration, assessment method, and management of visual midline shift syndrome following cerebrovascular accident. There is agreement on the existence of a midline shift following a cerebrovascular accident resulting in poor posture and imbalance. Much uncertainty exists in the literature regarding terminology, underlying pathophysiology, assessment method and management of this condition. Further research is required.     

Prospective LASIK trial for myopia and myopic astigmatism: 1-year results

A prospective, nonrandomized, unmasked, 1-year clinical trial was performed in 2482 eyes to evaluate the safety and efficacy of laser in situ keratomileusis (LASIK) for myopia and myopic astigmatism using a new excimer laser system. The study found that LASIK was a safe and effective method for correcting myopia and myopic astigmatism in patients with sphere to −15 diopters (D) and cylinder to 5 D. Dr. Kremer has a financial interest in the excimer laser system used in this study.