At a glance
Macular pseudoholes and lamellar holes
Differentiation between macular pseudoholes and lamellar holes can be difficult. 50 eyes of 46 consecutive patients diagnosed by OCT as having a foveal defect with residual retinal tissue were reviewed. Eyes classified as having pseudoholes (28) had macular centres and perifoveal retinas significantly thicker than the 22 eyes with lamellar macular holes. The corresponding corrected autofluorescence (AF) images were then evaluated. None of the control eyes showed foveal AF. Bottoni et al observed that AF imaging is superior to OCT data when differentiating between macular pseudoholes and lamellar holes, as presence of foveal AF is indicative of foveal tissue loss and, therefore, is diagnostic of a lamellar macular hole.
See pages 635
Autofluorescence of choroidal melanoma
Shields et al describe the autofluorescence features of choroidal melanoma in 51 consecutive patients. The choroidal melanoma showed intrinsic hypoautofluorescence (39%), isoautofluorescence (6%) and hyperautofluorescence (55%). Related RPE hyperplasia and atrophy showed hypoautofluorescence, drusen, RPE detachment and subretinal fluid showed slight hyperautofluorescence, and orange pigment displayed the brightest hyperautofluorescence.
See pages 617
Macular hole surgery
Macular holes surgery requires very inconvenient postoperative face-down positioning. In an effort to study effects of limited face-down positioning, Hasler and Prünte evaluated 30 eyes (30 patients) with unilateral full-thickness macular hole (stage II–IV) that underwent PPV, ILM peeling and fluid–air exchange followed by postoperative face-down positioning only for initial 2 days postoperatively. They observed macular hole closure rate of 93% at 1 year. The authors concluded that shorter face-down positioning resulted in surgical outcomes that are comparable with prolonged face-down positioning.
See pages 645
Photodynamic therapy in paediatric and young adult patients
Although uncommon, choroidal neovascularisation (CNV) may develop in children and young adults due to pathological myopia, ocular histoplasmosis, retinochoroiditis or trauma. Lipski et al conducted a prospective open-label photodynamic therapy (PDT) study in 16 eyes of 16 consecutive patients aged 30 years or younger. 81% of the patients either improved vision or maintained stable vision during a mean follow-up of 34 months. Alterations of the pigment epithelium increased in the area of PDT without changes in vision. The authors conclude that PDT is a valuable treatment even in young patients with CNV.
See pages 655
Intravitreal levofloxacin in experimental endophthalmitis
This study evaluated treatment with 1.5% levofloxacin compared with 1% vancomycin plus 2.2% ceftazidime in an experimental model of bacterial endophthalmitis. The right eye of 75 New Zealand white rabbits were inoculated in the vitreous cavity with strains of Staphylococcus epidermidis, Staphylococcus aureus or Pseudomonas aeruginosa. At 24 h after treatment, 100 μl of vitreous and aqueous humor were harvested, and the number of colony-forming units (CFU) per ml was determined. Overall there was no significant difference between levofloxacin and vancomycin plus ceftazidime. Ferrer et al concluded that levofloxacin appears to be effective in treating experimental endophthalmitis in the rabbit model. Further studies on the toxicity of intravitreal levofloxacin are required before clinical application is recommended.
See pages 678
Inner retinal dysfunction precedes ganglion cell loss in a mouse glaucoma model
In an attempt to correlate ganglion cell function with elevated IOP in a mouse glaucoma model and to determine the temporal relationship of these changes with ganglion cell death, Holcombe et al induced unilateral chronic ocular hypertension in C57BL6/J mice by laser ablation of the limbal episcleral veins. Scotopic flash electroretinograms (to isolate specific outer and inner retinal responses) were recorded at several intervals and peripheral and central ganglion cell densities were quantified by immunohistochemistry. The authors observed that inner retinal dysfunction preceded the progressive ganglion cell death, which correlated with the cumulative IOP insult, suggesting that a portion of the IOP-mediated ganglion cell dysfunction may be reversible.
See pages 683
