Intracranial Arterial Compression of the Anterior Visual Pathway.

Compression of anterior visual pathway (AVP) structures by intracranial arteries is observed not infrequently on neuroimaging. Whether or not such compression results in damage to these structures, however, remains unclear. This information is important to define as AVP compression by intracranial arteries may be a causative factor in patients with otherwise unexplained visual dysfunction. In a single centre, 37 patients with evidence of intracranial artery AVP compression demonstrated on magnetic resonance imaging were identified by retrospective review of case records over the period 2011-2017. Variables were collected, including patient demographics, visual acuity, visual fields, pupillary reactions and optic disc appearance for patients in the case series. Visual field deficits correlated with compression sites in the 37 patients examined. Internal carotid artery-optic nerve compression was the most frequent (unilateral compression n = 9, bilateral compression n = 14), followed by chiasmal compression by the anterior cerebral artery (n = 8) and a combination of optic nerve and chiasmal compression (n = 5). Visual acuity and visual fields were stable on follow-up (mean 4 years) in 24 of 26 cases (93%). We conclude that AVP compression by intracranial arteries may be a causative factor in unexplained visual dysfunction. The visual defects are largely non-progressive.

Comparison between intraocular pressure spikes with water loading and postural change.

BACKGROUND: To compare the agreement between peak intraocular pressures measured through the water drinking test and the supine test, in patients with primary open angle glaucoma. DESIGN: Consecutive, prospective, blinded. PARTICIPANTS: Twenty-one patients from the Glaucoma Unit, Prince of Wales Hospital, Sydney, Australia. METHODS: For the supine test, intraocular pressure was recorded immediately after the patient had lain down and at 20 and 40 min. At the second evaluation, intraocular pressure was measured in each patient after drinking 10 mL/kg body weight of water for the water drinking test. Again, all patients had their intraocular pressure measured at 20 and 40 min (t = 20 and t = 40, respectively). Patients were excluded from the study if they had pre-existing cardiac, renal or pulmonary complications or had concurrent ocular disease or an anatomical abnormality (including angle recession, peripheral anterior synechiae and developmental anomalies of the angle) that may have influenced intraocular pressure. MAIN OUTCOME MEASURE: Bland-Altman analysis. RESULTS: Bland-Altman analysis indicated an overall excellent agreement in terms of mean difference between methods (1.0, -1.0 and -0.90 mmHg, at 0, 20 and 40 min, respectively). Further, with the exception of t = 40, all measured time points had 95% confidence intervals within 6.5 mmHg of their mean difference on the Bland-Altman plot. CONCLUSIONS: There was close agreement between the intraocular pressure values of the supine test and water drinking test. However, as the water drinking test may be uncomfortable and potentially hazardous, there is potential that the supine test may be a safer and more comfortable alternative.

Utilisation of a Novel Test to Measure Severity and Treatment Efficacy of Posterior Blepharitis.

Background. This study evaluated the effectiveness of managing posterior blepharitis (PB) using a novel Posterior Blepharitis Management Protocol (PBMP). Design. Prospective, consecutive case series with 100% followup to one month. Participants. 27 patients (54 eyes) with PB from an Ophthalmology practice in Sydney, Australia. Methods. Each patient's PB was assessed by grading the nature and expressibility of the central lower lid tarsal gland secretions on Compression Of The Eyelid (COTE). Patients were then instructed in detail to undertake daily PB management sessions at home using our modified PBMP. Main Outcome Measures. On a subjective scale, patients compared their symptoms at one month with baseline. COTE scores were reevaluated to assess the objective effectiveness of each individual's PBMP. COTE scoring was described as grades 1 (clear oil), 2 (pus, liquid), 3 (toothpaste-like secretions), and 4 (complete tarsal gland obstruction). Results. Patients reported a mean 77.8% ± 13.5% subjective improvement in symptoms. There was a trend towards improvement in COTE grading at one month compared with baseline: grades 1 (0 to 7.4%), 2a (22.2 to 16.6%), 2b (7.4 to 3.7%), 3 (18.5 to 27.7%), and 4 (51.8 to 44%). Conclusions. PBMP provided a rapid, inexpensive, simple, effective, and safe method of treating PB.