Transient Visual Loss after Retrobulbar Anesthesia in the Advanced Glaucoma Patients

Retrobulbar Anesthesia is injecting local anesthetics into the retrobulbar space within the muscle cone, which affects the third cranial nerve, ciliary ganglion and optic nerve. Proper retrobulbar anesthesia can temporarily weaken somatosensory, motor and visual sensory. It also narrows visual fields. However, it does not result in complete loss of visual acuity. According to the authors, all 4 advanced cases which showed transient and complete visual loss after retrobulbar anesthesia of Lidocaine Hcl[2% lidocaine, einephrine, 1:100,000] were advanced glaucoma patients who had normal fundus except glaucomatous change and self-recovered within 1 to 4 hours. The decrease in vision may be related to the effects of the anesthetic agent on the optic nerve, or it may be related to the relative ischemia produced by compression, or caused by entopsias induced by compression. The authors cases suggest that transient visual loss after retrobulbar anesthesia may not reduce postoperative visual acuity and visual fields in the advanced glucoma patients.

A Comparison of Cyclocryotherapy and Contact Transscleeral Cyclophotocoagulation with Diode Laser in Rabbit

Cyclodestruction is generally achieved by applying thermal energy across the intact sclera. Commonly employed modalities are ultrasound, cryopexy, diathermy, noncontact laser light and most recently, contact transscleral laser using argon, krypton and Nd:YAG, diode laser. This study was performed to compare the pressure lowering and tissue effects of contact transscleral cyclophotocoagulation(TSCPC) with diode laser using G prode to cyclocryotherapy in rabbit. The results of this study demonstrate a similar intraocular pressure lowering effect of both cyclocryotherapy and contact TSCPC with diode laser using G prode. Histologic studies showed that both TSCPC and cyclocryotherapy are effective anatomic cyclodetructive modalities but in case of TSCPC, less severe destruction of ciliary body was noted. This study indicated that contact TSCPC with diode laser using G probe delivery provieds effective and safe management for eyes with medically and surgically uncontrolled glaucoma compared to cyclocryotheraphy.

Photic Retinal Injury Induced by Endoillumination during Vitrectomy

Photic retinal injuries following operating microscopic light exposure or endoillumination are produced by mechanical, thermal or photochemical mechanism. The authors experienced a case of a patient who developed a round macular lesion which seemed to be a light-induced retinal damage during pars plana vitrectomy and removal of intraretinal foreign body.