Akiomi Takano

Plasmin-assisted vitrectomy for management of proliferative membrane in proliferative diabetic retinopathy: a pilot study.

Purpose: To demonstrate the feasibility of autologous plasmin for treatment of proliferative diabetic retinopathy. Methods: The study examined prospectively six patients with bilateral proliferative diabetic retinopathy. Comparisons of the surgical time and the incidence of retinal tears were made between the eyes treated with autologous plasmin and their respective opposite eyes, which were treated without plasmin. Results: All eyes treated with autologous plasmin required significantly less surgical time (68 versus 89 minutes, P = 0.04, paired t-test). In the plasmin group, no additional surgical procedures for removing the proliferative membrane were needed, including membrane delamination or segmentation. Moreover, with plasmin pretreatment, there were no retinal tears, which was in contrast to the control group, where three eyes with retinal tears were observed. There was no significant difference found between the two groups for final visual outcomes. Conclusion: Autologous plasmin may be beneficial in the surgical management of proliferative diabetic retinopathy.

Pitavastatin: Protection against Neuronal Retinal Damage Induced by Ischemia-Reperfusion Injury in Rats

Purpose: To evaluate the neuroprotective effects of pitavastatin against neuronal retinal damage induced by ischemia-reperfusion injury in rats. Methods and Results: Ischemia-reperfusion injury was induced in Sprague-Dawley rats using ocular hypertension. Pitavastatin (0.1, 0.5, or 1.0 mg/kg) was given intravenously 12 hr or 5 min before, or 12 or 24 hr after the induction of ischemia-reperfusion injury. Morphometric and retrograde labeling analyses revealed neuroprotective effects when pitavastatin (0.5 mg/kg) was administered 5 min before—even 12 and 24 hr—after induction of ischemia-reperfusion injury. These effects depended on dose; protection was noted at pitavastatin concentrations of 0.5 and 1 mg/kg but not 0.1 mg/kg. Furthermore, preadministration of pitavastatin (0.5 mg/kg) reduced expression of P-selectin and intercellular adhesion molecule-1 at 12 and 24 hr after induction of ischemia-reperfusion injury. Conclusions: As pitavastatin was efficacious in preventing retinal neuronal death, it may be a novel therapeutic modality for ischemic retinal diseases.

Trans-Tenon's retrobulbar triamcinolone acetonide injection for macular oedema related to branch retinal vein occlusion.

Background: The aim of the study was to evaluate the safety and effectiveness of trans-Tenon’s retrobulbar triamcinolone acetonide (TA) injection for macular oedema associated with branch retinal vein occlusion (BRVO). Methods: We reviewed the medical records of 50 consecutive patients with macular oedema associated with BRVO who were treated with trans-Tenon’s retrobulbar TA injection (20 mg) as initial treatment for a follow-up period of at least 12 months. Foveal thickness determined by optical coherence tomography, visual acuity, intraocular pressure (IOP) and cataract progression were measured. Results: The mean duration between oedema onset and TA injection was 4.9 months. Foveal thickness decreased significantly at 3 months after injection (p<0.0001). Furthermore, the percentage reduction in foveal thickness in eyes with posterior vitreous detachment (PVD; n = 23) was significantly greater than that without PVD (n = 27, p = 0.003). Improved visual acuity by at least 0.20 log minimum angle of resolution (logMAR) was seen in 22 eyes (44%; 11 eyes with PVD and 11 eyes without PVD). After completion of the 3-month follow-up, 29 eyes (58%) needed additional treatment including TA injections or pars plana vitrectomy (PPV). PPV seemed to be effective for macular oedema resistant to TA. IOP elevation and cataract progression occurred in less than 10% of all patients. Conclusions: Trans-Tenon’s retrobulbar TA injection appeared safe and relatively effective for macular oedema associated with BRVO. In eyes resistant to TA injection, PPV may be effective as an adjunctive treatment.