Variations in optic nerve head morphology by intraocular pressure in open-angle glaucoma.

PURPOSE: To compare optic disc topography in eyes in three intraocular pressure (IOP) groups of <15 mmHg, 15-20 mmHg, and ≥21 mmHg using spectral domain optical coherence tomography (SD-OCT) and confocal scanning laser ophthalmoscopy, adjusting for the degree of damage, as measured by retinal nerve fiber layer (RNFL) thickness and average visual field loss. METHODS: A total of 184 eyes of 112 patients with primary open-angle glaucoma were recruited into groups based on baseline untreated intraocular pressure (IOP) of <15 mmHg (normal-tension glaucoma [NTG], very low), 15-20 mmHg (NTG, medium), or ≥21 mmHg (high-tension glaucoma [HTG]). Patients underwent scanning laser ophthalmoscopy, SD-OCT, and Humphrey visual field testing. Univariate and multivariate models were created, accounting for degree of retinal ganglion cell (RGC) loss by either OCT RNFL thickness or visual field mean deviation (MD). RESULTS: Univariate and multivariate analyses demonstrated no morphological differences in HRT or OCT parameters among IOP groups that met Bonferroni-corrected statistical significance when using either MD or OCT RNFL as the damage criterion (p < 0.0063). The mean cup depth was shallower for the IOP <15 mmHg group than the IOP ≥21 mmHg group (p < 0.05) for both MD (p < 0.011) and OCT RNFL (p < 0.014). CONCLUSION: Normal-tension and high-tension glaucoma are not distinguishable by optic nerve head topography with HRT and OCT when the degree of damage by Humphrey visual field testing is taken into account.

New developments in giant cell arteritis.

Giant cell arteritis (GCA) is a medium-to-large vessel vasculitis with potentially sight- and life- threatening complications. Our understanding of the pathogenesis, diagnosis, and treatment of GCA has advanced rapidly in recent times. The validity of using the American College of Rheumatology guidelines for diagnosis of GCA in a clinical setting has been robustly challenged. Erythrocyte sedimentation rate, an important marker of inflammation, is lowered by the use of statins and nonsteroidal anti-inflammatory drugs. Conversely, it may be falsely elevated with a low hematocrit. Despite the emergence of new diagnostic modalities, temporal artery biopsy remains the gold standard. Evidence suggests that shorter biopsy lengths and biopsies done weeks to months after initiation of steroid therapy are still useful. New imaging techniques such as positron emission tomography have shown that vascular inflammation in GCA is more widespread than originally thought. GCA, Takayasu arteritis, and polymyalgia rheumatica are no longer thought to exist as distinct entities and are more likely parts of a spectrum of disease. A range of immunosuppressive drugs have been used in conjunction with corticosteroids to treat GCA. In particular, interleukin-6 inhibitors are showing promise as a therapy.

Visual symptoms in the presentation of Creutzfeldt-Jakob disease.

We describe a 68-year-old man with a previous history of neurosurgical repair of a skull fracture, who presented to the ophthalmology clinic with progressive visual decline. His initial visual acuity was 6/30 in the right eye and 6/48 in the left, and over 2 weeks this progressed to hand movements in both eyes. No ocular abnormalities were identified. He was noted to be increasingly confused and a subsequent MRI showed extensive bilateral posterior cortical changes consistent with cytotoxic oedema. An electroencephalogram was suggestive of encephalopathy, particularly involving the occipital lobe. He was diagnosed with the Heidenhain variant of Creutzfeldt-Jakob disease (CJD), confirmed by a positive cerebrospinal fluid 14-3-3 protein. Classically, patients with CJD present with rapidly progressive cognitive decline, ataxia and myoclonus. However, visual symptoms are a common and perhaps underrecognised manifestation of CJD. Patients can present with isolated visual symptoms which precede cognitive decline by weeks due to predominantly occipital lobe disease. This presentation is classified as the Heidenhain variant of CJD.

Optical coherence tomography predicts visual outcome for pituitary tumors.

We evaluate if the relationship between optical coherence tomography (OCT) of the retinal nerve fibre layer (RNFL) and visual outcome continued over long-term visual recovery in 107 patients undergoing pituitary decompression. Recently, it has been recognized that OCT of the RNFL has prognostic value in predicting visual outcomes after surgery for chiasmal compression caused by pituitary tumours. Patients were followed up at three time points: pre-operative (visit 1), 6-10 weeks post-operative (visit 2) and 9-15 months follow-up (visit 3). We found that patients with thin pre-operative RNFL had more severe visual field defects (mean deviation [MD] -9.22 versus -3.96 decibels [dB]; p = 0.001), but pre-operative visual acuity (VA) was good in both normal and thin RNFL groups (Snellen VA 6/5 and 6/4; p = 0.039). For those with thin RNFL the greatest improvement was between visit 2 and 3 (MD -7.1 dB versus -3.4 dB, respectively; p < 0.001) compared with pre-operative -9.8 dB. Normal RNFL patients showed greatest improvement between visits 1 and 2 (pre-operative -4.8 dB, visit 2 -2.0 dB, visit 3 -0.9 dB; p = 0.001). For long-term follow-up, 81.0% of eyes with normal RNFL, compared to 37.1% with thin RNFL (p < 0.001), achieved an MD of -2.00 dB (final visit). At final follow-up, 97.5% of normal RNFL eyes achieved VA of 6/12 or better compared with 88.2% with thin RNFL (p = 0.034). Our results indicate that long-term visual recovery after surgical decompression of pituitary lesions is predicted by pre-operative OCT RNFL. Patients with normal RNFL thickness show an increased propensity for visual recovery. This effect continues after long-term follow-up, however, most visual recovery occurs within the first 6-10 weeks.