Images of intravitreal objects projected onto posterior surface of model eye.

PURPOSE: To try to recreate the images reported by patients during vitreous surgery in a model eye. METHODS: A fluid-filled model eye with a posterior frosted translucent surface which corresponded to the retina was used. Three holes were made in the model eye through which an endoillumination pipe and intraocular forceps could be inserted. A thin plastic sheet simulating an epiretinal membrane and an intraocular lens (IOL) simulating a dislocated IOL were placed on the retina. The images falling on the posterior surface were photographed from the rear. The images seen through the surgical microscope were also recorded. RESULTS: The images from the rear were mirror images of those seen through the surgical microscope. Intraocular instruments were seen as black shafts from the rear. When the plastic sheet was picked up, the tip of the forceps was seen more sharply on the posterior surface. The images of the dislocated IOL from the posterior were similar to that seen through the surgical microscope, including the yellow optics and blue haptics. CONCLUSION: Intravitreal objects can form images on the surface of a model eye. Objects located closer to the surface are seen more sharply, and the colour of the objects can be identified.

Transpupillary thermotherapy for atypical central serous chorioretinopathy.

BACKGROUND: Central serous chorioretinopathy (CSC) has been traditionally treated with laser photocoagulation. We thought that transpupillary thermotherapy (TTT) utilizing a lower temperature than that of conventional laser photocoagulation might minimize permanent retinal and choroidal damage. Studies suggest that undesirable effects on vision due to TTT are minimal even if it is applied to foveal and/or parafoveal lesions when TTT requires a larger irradiation spot. The aim of this study was to evaluate the efficacy of TTT in the management of atypical CSC. METHODS: We defined atypical CSC as bullous retinal detachment with diffuse or several leakages, severe leakage with fibrin formation under serous retinal detachment, or leakage within a pigment epithelium detachment. Eight consecutive patients with atypical CSC underwent visual acuity testing, ophthalmic examination, color photography, fluorescein angiography, and optical coherence tomography to evaluate the results of transpupillary thermotherapy. Retreatment of atypical CSC was based on ophthalmic examination, optical coherence tomography, and fluorescein angiography. TTT was performed on the leaking spots shown in fluorescein angiography, with a power of 50-250 mW, spot size of 500-1200 µm, and exposure time of 13-60 seconds to minimize retinal damage. RESULTS: In five of eight affected eyes, serous detachments completely resolved within 1 month after the initial TTT. One eye had persistent subretinal fluid and required a second TTT treatment. Two eyes showed no resolution of CSC and were treated by conventional photocoagulation. Initial best-corrected visual acuity (BCVA) ranged from 20/600 to 20/20 (mean, 20/40; median, 20/30). Final BCVA ranged from 20/200 to 20/20 (mean, 20/25; median, 20/20). BCVA improved in all cases. Only two eyes with persistent subretinal fibrin and existing retinal pigment epithelial alternations in macular area showed limited improvement of BCVA despite the absence of subretinal exudation. The presence of retinal attachment was confirmed by optical coherence tomography in six eyes (75%). CONCLUSIONS: TTT seems to be effective for the treatment of atypical CSC in the short term. Additional studies are necessary to evaluate the long-term effectiveness and safety.

Incidence of increased intraocular pressure after subtenon injection of triamcinolone acetonide.

PURPOSE: To determine the incidence of eyes that have an increase in the intraocular pressure (IOP) after subtenon injections of triamcinolone acetonide (TA). METHODS: The medical records of 147 patients treated with single or multiple subtenon injections of TA (10 mg) were reviewed. The incidence of an IOP elevation (ΔIOP) ≥5 mmHg or an IOP of >21 mmHg was determined. The peak ΔIOP, defined as the difference in the IOP at the peak to the baseline IOP, was also evaluated. Multivariate analyses were used to evaluate the relation between the IOP elevation and the age, gender, refractive error, and lens status. RESULTS: A ΔIOP ≥5 mmHg was found in 75 eyes (46%), and an IOP >21 mmHg was found in 48 eyes (30%) after a single injection of TA. The IOP increased within 3 months in 39 eyes (81%) and after 4 months in 9 eyes (19%). The IOP began to increase significantly from 2 weeks up to 5 months (P<0.05) and returned to the baseline IOP in 10 months. The incidence of ΔIOP ≥5 mmHg or an IOP of >21 mmHg after multiple subtenon injections of TA was significantly higher than after a single injection (62%; P=0.027, 47%; P=0.013, respectively). The incidence of IOP >21 mmHg and the peak ΔIOP were significantly related with younger age (P=0.002, P=0.021, Forward stepwise regression analysis). A weak but significant negative correlation was found between the peak ΔIOP and the age (r=-0.216, P=0.006, Pearson's correlation coefficient test), and the peak ΔIOP and the refractive error (r=-0.198; P=0.018). CONCLUSION: Repeated injections of TAs and injection of younger patients or myopic eyes increase the incidence of an IOP elevation.

Selective laser trabeculoplasty for elevated intraocular pressure following subtenon injection of triamcinolone acetonide.

PURPOSE: To report on the efficacy of selective laser trabeculoplasty (SLT) for elevated intraocular pressure (IOP) following subtenon injection of triamcinolone acetonide. METHOD: SLT was performed on four of 148 eyes in which IOP was elevated after a subtenon injection of triamcinolone acetonide and could not be maintained within normal limits by conventional medications. Postoperative IOP and relative reduction of IOP were evaluated. RESULTS: IOP was reduced in three eyes to within the normal range without any medications six months after SLT alone, but trabeculotomy was performed on one eye. Percentage reduction in IOP after SLT was 21.6% at one month, 45.0% at three months, and 52.7% at nine months. CONCLUSION: SLT may be effective in reducing elevated IOP following subtenon injection of triamcinolone acetonide and should be considered before glaucoma surgery.

Pupillary Block Glaucoma After Implantation of Iris-Fixated Phakic Intraocular Lens.

To report a case of pupillary block glaucoma after implantation of iris-fixated phakic intraocular lens (IF pIOL). A 43-year-old man was referred for pupillary block one day after implantation of IF pIOL. Slit-lamp examination revealed extremely shallow anterior chamber, closure of peripheral laser iridotomy and contact of iris on the peripheral of the optics of IF pIOL. The intraocular pressure (IOP) was 62 mm Hg. The iris moved forward in contact with the IF pIOL and the lens remained in the physiologic position, which made the distance between the lens and the iris wide. He underwent an uneventful peripheral surgical iridectomy and the IOP decreased to 6 mm Hg. Acute pupillary block glaucoma can occur after IF pIOL implantation due to the occlusion of aqueous flow between the IF pIOL and the iris if the peripheral iridotomy closes.

Dehiscence of levator aponeurosis in ptosis after sub-Tenon injection of triamcinolone acetonide.

OBJECTIVE: To report the incidence, intraoperative findings, and surgical outcome of secondary ptosis that developed after a sub-Tenon injection of triamcinolone acetonide (TA). STUDY DESIGN: Retrospective, cross-sectional study. PARTICIPANTS: One hundred forty-seven cases with a total of 286 sub-Tenon TA injections. METHODS: The medical records of 163 eyes of 147 cases treated with a sub-Tenon injection of 10 mg or 20 mg TA were reviewed. The incidence of secondary ptosis (palpebral fissure >2 mm narrower than that of the fellow eye) after a sub-Tenon TA injection was determined. The preoperative levator function and margin reflex distance (MRD) of the affected eyes, and the intraoperative findings in eyes that underwent reconstructive surgery, were evaluated. RESULTS: Eight eyes (5%) developed secondary ptosis after the injection and 6 eyes were treated by reconstructive surgery. The preoperative levator function of the affected eyes did not differ from that of the fellow eyes. Intraoperatively, no septal disruption or fat herniation was noted, but an aponeurotic disinsertion was identified and repaired with an advancement of the leading edge to the anterior tarsal plate. The surgery led to satisfactory results, with improvement of the MRD from -1.3 (SD 1.5) mm preoperatively to 2.3 (SD 0.5) mm postoperatively (p = 0.027). Additional sub-Tenon TA injections were required in 2 eyes after eyelid surgery but the ptosis did not worsen. CONCLUSIONS: A sub-Tenon TA injection can occasionally cause ptosis by inducing a disinsertion of the levator aponeurosis. However, surgical reconstruction can lead to successful resolution of the ptosis.

Accommodative loss after retinal cryotherapy.

PURPOSE: To investigate the effects of peripheral retinal cryotherapy on accommodative amplitude in patients with retinal lattice degeneration. DESIGN: Prospective, observational case series. METHODS: We studied 92 eyes in 69 patients (age range, 13 to 79 years) treated with cryotherapy for lattice degeneration between December 2001 and September 2004. Pretreatment and posttreatment accommodative amplitudes were measured. Acute accommodative loss was calculated from the difference between accommodative amplitudes before treatment and one week after treatment. We investigated the time course of accommodative amplitudes, acute accommodative loss in different age groups and in pretreatment accommodative amplitude groups, the influence of cryotherapy numbers on accommodative amplitude, and the influence of cryotherapy sites on accommodative amplitude. RESULTS: No significant difference was noted between pretreatment and posttreatment accommodative amplitudes in the overall subject cohort. Dividing subjects by age revealed significant decreases in accommodative amplitude only among patients in their 10s and 20s at one and three weeks after treatment. Accommodative amplitude was lowest among those in their 10s, followed by that among those in their 20s (P < .01). Accommodative amplitudes recovered to pretreatment level by six weeks. Acute accommodative loss was greatest in those in their 10s compared with other age groups (P < .01). A significant correlation was observed between acute accommodative loss and cryotherapy numbers (P = .03; r = 0.41). CONCLUSIONS: The decrease in accommodative amplitude was greatest at one week after treatment and recovered to pretreatment levels after six weeks. Accommodative amplitude showed the greatest decrease after cryotherapy among patients in their 10s and 20s. A decrease in accommodative amplitude was observed with increased numbers of cryotherapy spots administered.

Two-step oblique incision during 25-gauge vitrectomy reduces incidence of postoperative hypotony.

The efficacy of a two-step, oblique incision procedure during 25-gauge vitrectomy on postoperative hypotony was evaluated by a retrospective, case-control study. The transconjunctival incision during 25-gauge vitrectomy was made in two steps: penetration with a microvitreoretinal blade followed by a penetrater instrument of a blunt trocar. The two-step procedure was performed on 89 eyes and with the conventional incision on 68 eyes. The incidence of hypotony (intraocular pressure <6 mmHg) on the first postoperative day and after 1 week and 1 month was compared. Hypotony was found in two eyes (2%) with the two-step method and 12 eyes (18%) with the conventional incision on the first postoperative day (P = 0.001, Fisher's exact probability test). The preoperative intraocular pressure was not significantly different in the two groups but was significantly higher in the two-step group than in the conventional method group on the first postoperative day (P = 0.001, Wilcoxon rank test). Twenty-five-gauge vitrectomy with two-step oblique incisions will reduce the incidence of postoperative hypotony on the first postoperative day.

25-gauge cannula system with microvitreoretinal blade trocar.

PURPOSE: To report a 25-gauge trocar-cannula that enhances wound closure and reduces the incidence of postoperative hypotony. DESIGN: Development of surgical instruments. METHODS: A 25-gauge cannula with a microvitreoretinal (MVR) blade trocar was constructed. The resistance of inserting this trocar cannula was compared with that of the conventional 25-gauge trocar cannula (Alcon Laboratories; Fort Worth, Texas, USA). Vitreous surgery was performed on 55 eyes with the trocar cannula with an oblique sclerotomy incision, and the results were compared with those from 68 eyes that underwent surgery with the conventional trocar cannula. RESULTS: The resistance of inserting the trocar cannula was less than that with the conventional trocar cannula. A temporary hypotony (intraocular pressure [IOP] <6 mm Hg) was found in one eye (2%) with the trocar cannula and in 12 eyes (18%) with the conventional trocar cannula (P = .006, Fisher exact probability test). CONCLUSIONS: The trocar cannula with a MVR blade was effective in postoperative wound closure and prevention of postoperative hypotony.