23-gauge versus 25-gauge vitrectomy for proliferative diabetic retinopathy: a comparison of surgical outcomes.

PURPOSE: This study compared clinical outcomes and complications between 23-gauge (23g) and 25-gauge (25g) transconjunctival sutureless vitrectomy in patients with proliferative diabetic retinopathy. STUDY DESIGN: It was a retrospective study using data prospectively defined and collected. 80 eyes underwent 23g transconjunctival sutureless vitrectomy, and 80 eyes underwent 25g surgery using the same vitrectomy system by one surgeon. Primary outcome measures were best-corrected visual acuity, intraocular pressure (IOP), and incidence of intraoperative and postoperative complications. RESULTS: Vision was significantly improved after intervention in both groups (p ≥ 0.0001). There was no significant difference in visual outcomes between the groups (p = 0.43) or in the type and frequency of retinal breaks occurring during surgery (p = 0.63). The 23g group had significantly more patients with a day 1 IOP of <6 mm Hg (p = 0.034) and significantly more patients requiring a sclerostomy suture postoperatively (p = 0.014). CONCLUSION AND MESSAGE: Both gauges are equally effective for the treatment of proliferative diabetic retinopathy.

Extraocular muscle atrophy and central nervous system involvement in chronic progressive external ophthalmoplegia.

BACKGROUND: Chronic progressive external ophthalmoplegia (CPEO) is a classical mitochondrial ocular disorder characterised by bilateral progressive ptosis and ophthalmoplegia. These ocular features can develop either in isolation or in association with other prominent neurological deficits (CPEO+). Molecularly, CPEO can be classified into two distinct genetic subgroups depending on whether patients harbour single, large-scale mitochondrial DNA (mtDNA) deletions or multiple mtDNA deletions secondary to a nuclear mutation disrupting mtDNA replication or repair. The aim of this magnetic resonance imaging (MRI) study was to investigate whether the ophthalmoplegia in CPEO is primarily myopathic in origin or whether there is evidence of contributory supranuclear pathway dysfunction. METHODS: Ten age-matched normal controls and twenty patients with CPEO were recruited nine patients with single, large-scale mtDNA deletions and eleven patients with multiple mtDNA deletions secondary to mutations in POLG, PEO1, OPA1, and RRM2B. All subjects underwent a standardised brain and orbital MRI protocol, together with proton magnetic resonance spectroscopy in two voxels located within the parietal white matter and the brainstem. RESULTS: There was evidence of significant extraocular muscle atrophy in patients with single or multiple mtDNA deletions compared with controls. There was no significant difference in metabolite concentrations between the patient and control groups in both the parietal white matter and brainstem voxels. Volumetric brain measurements revealed marked cortical and cerebellar atrophy among patients with CPEO+ phenotypes. CONCLUSION: The results of this study support a primary myopathic aetiology for the progressive limitation of eye movements that develops in CPEO.