External Trabeculectomy with T-Flux Implant

PURPOSE

To evaluate the efficacy and safety of T-Flux implant in nonpenetrating glaucoma surgery.

METHODS

This clinical interventional case series study included 35 eyes of 35 patients with medically uncontrolled primary open angle glaucoma. External trabeculectomy with T-Flux (ETTF) is a technique of nonpenetrating glaucoma surgery, in which after removing deep scleral tissue and un-roofing the canal of Schlemn (CS) the external trabecular tissue is peeled off to enhance the aqueous drainage without opening the anterior chamber. A non-absorbable T-Flux implant (IOL TECH Laboratories, France) was sutured in deep intrascleral space to keep it patent. Snellen's best-corrected visual acuity, slit lamp biomicroscopy, intraocular pressure (IOP), gonioscopy, funduscopy, and optic disc assessment were performed preoperatively and postoperatively at 1 day, 1 week, and 1, 3 , 6, and 12 months. Visual field testing was performed preoperatively and at 6 and 12 months postoperatively.

RESULTS

For three eyes, surgery was converted to standard trabeculectomy owing to the perforation of trabeculo-Descemet's membrane and iris prolapse and excluded from the study. The results of the remaining 32 eyes were included in the study. Preoperative IOP (mean +/- SD) of 32.88 +/- 5.7 mmHg decreased to 15.44 +/- 1.6 mmHg after 12 months. Ten eyes (28.6%) had microhyphema that resolved spontaneously; 3 eyes (8.6%) had microperforation without iris prolapse so ETTF was proceeded routinely. The preoperative number of antiglaucoma medications per patient reduced from (mean +/- SD) 2.74 +/- 0.61 to 0.11 +/- 0.32 postoperatively at 12 months. Visual acuity and visual fields remained stable.

CONCLUSIONS

ETTF appears to provide significant control of IOP and have low incidence of complications.

Can a preoperative bevacizumab injection prevent recurrent postvitrectomy diabetic vitreous haemorrhage?

AIMS

To evaluate the recurrence rate of vitreous haemorrhage (VH) in patients treated with one intravitreal bevacizumab (IVB) injection (2.5 mg/0.1 ml) before planned pars plana vitrectomy for treatment of diabetic non-clearing VH.

METHODS

Prospective pilot study of 32 eyes of 31 consecutive diabetic patients who underwent IVB injection within 1 week before surgery for persistent VH in the presence of active proliferative diabetic retinopathy. Three masked retinal specialists graded the amount of VH from grade 0 to grade 3 with slit-lamp biomicroscopy. Main outcome measures were the rate of recurrence of the VH, improvement in visual acuity, incidence of cataract formation, and postoperative complications through a follow-up of 6 months.

RESULTS

The percentage of severe recurrent VH with no fundus details (grade 3) was 3% at 1 week follow-up and 3, 6, and 6% respectively at 1-, 3-, and 6-month follow-up. The mean best-corrected visual acuity (BCVA) improved from 1.6 (1/60) to 0.40 (6/15) logMAR (P=0.02) in 29 out of 32 eyes (91%). In all, 12 out of 22 (54%) phakic eyes developed cataract during the follow-up period, and 10 (31%) of them underwent cataract surgery.

CONCLUSIONS

Our study suggests that IVB injection few days before planned surgery seems to be efficacious and safe as an adjuvant treatment to prevent rebleeding in eyes undergoing pars plana vitrectomy for treatment of diabetic vitreous haemorrhage. IVB facilitates the surgery and reduces the need for extensive delamination and segmentation, decreasing the possibility of significant early active postoperative VH.

Optical coherence tomographic pattern may predict visual outcome after intravitreal triamcinolone for diabetic macular edema

OBJECTIVE

To identify an optical coherence tomography (OCT) pattern predictive of visual outcome in patients with diabetic macular edema (DME) who underwent a single dose of intravitreal triamcinolone.

DESIGN

Retrospective case analysis with prospective data collection for controls.

PARTICIPANTS

Ninety-three cases and 25 controls.

METHODS

Two independent masked observers retrospectively examined preoperative macular OCTs of 93 eyes of 93 patients who were given a single dose (4 mg in 0.1 ml) of intravitreal triamcinolone for DME and categorized them as belonging to 2 groups: 1, comprised of eyes with high reflectivity (bright colors) from inner retinal layers, and 2, comprised of eyes that had low reflectivity (darker colors) from inner retinal layers. Logarithm of the minimum angle of resolution visual acuity (VA) and macular thickness measured by OCT were assessed preoperatively and postoperatively at 1 and 3 months.

MAIN OUTCOME MEASURES

Optical coherence tomographic appearance of inner retinal layers.

RESULTS

All patients completed 3 months of follow-up. In group 1, 45 of 51 eyes (88%) experienced visual improvement of > or =2 lines on an Early Treatment Diabetic Retinopathy Study (ETDRS) chart at 1 month of follow-up. Forty-four of 51 patients (86%) experienced visual improvement of > or =2 lines on an ETDRS chart at 3 months of follow-up. In group 2, 18 of 42 patients (43%) experienced visual improvement of > or =1 lines on an ETDRS chart at 1 and 3 months of follow-up. For the remaining patients, VA remained unchanged during the postoperative course of 3 months.

CONCLUSIONS

Patients in whom OCT demonstrated the high reflectivity of inner retinal layers achieved greater VA though macular thickness decreased significantly after intravitreal triamcinolone in both groups. It may be hypothesized that a lower optical reflectivity of inner retinal layers is related to the atrophy of the inner retinal layers, thus resulting in a failure of VA recovery in these patients. The level of reflectivity from inner retinal layers on OCT may provide objective criteria in predicting the response of DME to intravitreal triamcinolone and help in preoperative counseling of patients with DME.

Histological findings of a choroidal neovascular membrane removed at the time of macular translocation in a patient previously treated with intravitreal bevacizumab treatment (Avastin)

AIM

To report the findings in a patient treated by repeated intravitreal bevacizumab (Avastin) injections, followed by macular relocation and excision of subfoveal choroidal neovascular membrane (CNV).

METHODS

Histopathological evaluation of the CNV specimen, including immunohistochemical assessment.

RESULTS

During surgical excision, the CNV seemed to be avascular and its underlying bed did not bleed. Histopathological examination revealed that the CNV comprised avascular fibrous subretinal tissue containing fibroblastic retinal pigment epithelial (RPE) cells, fragments of irregular thickened Bruch's membrane and fibrotic choroidal tissue containing some medium-sized vessels but no choriocapillaris.

CONCLUSIONS

The development of an RPE tear during the course of Avastin treatment may reflect contraction of the avascular subretinal tissue, whereas the lack of capillaries in both choroidal and subretinal components may be caused by the increased access of Avastin to the choriocapillaris in the presence of the RPE tear.

Ocular coherence tomographic examination of postoperative foveal architecture after scleral buckling vs vitrectomy for macular off retinal detachment

AIMS

This pilot study uses Optical Coherence Tomography (OCT) imaging to compare the difference in foveal architecture after successful retinal detachment (RD) surgery by scleral buckling or pars plana vitrectomy (PPV).

METHODS

Prospective recruitment of patients with macular off RDs. Detachment surgery was undertaken by scleral buckling, external drainage, and air injection (group 1) or by PPV (group 2). Postoperatively patients had clinical examinations and OCT at 1, 3, 6, and 12 months. If abnormalities persisted, a further OCT was obtained at 18 months.

RESULTS

Retinal reattachment, including clinical macular reattachment, was achieved in all cases within 24 h postoperatively. In group 1 (n=22), postoperative OCT showed persistent foveal detachment in 63% of cases (n=14) at 1 and 3 months. At 6 and 12 months, 36% (n=8) and 9% (n=2) had a persistent foveal detachment, respectively, and at 18 months, foveal detachment eventually. In group 2 (n=21), postoperative OCT showed an attached fovea in all cases; however, foveal thickening suggesting intraretinal oedema was present in all cases. The oedematous appearance of retina on OCT settled in 1-3 months. No foveal abnormality was seen at 6 and 12 months postoperatively.

CONCLUSIONS

A high proportion of patients with successful retinal reattachment surgery by scleral buckling had foveal detachments postoperatively. No cases who had PPV had foveal detachments; however, transient retinal oedema was evident in all cases. The aetiology of these changes is unknown and warrants further investigation, as there is the potential of a long-term effect on vision.

Foveal detachment after successful retinal reattachment for macula on rhegmatogeneous retinal detachment: an ocular coherence tomography evaluation

PURPOSE

Foveal detachment after apparently successful retinal reattachment surgery for macula-on retinal detachments (RDs) has been previously documented. This pilot study aimed to utilize ocular coherence tomography (OCT) imaging to investigate foveal architecture after routine retinal detachment surgery and correlate this to visual acuity.

METHODS

Prospective recruitment of patients attending one unit with macula-on RDs. Patients underwent full clinical examination including OCT preoperatively and RD surgery undertaken by scleral buckling, external drainage and air injection. Postoperatively patients had clinical examinations and OCT at 1 week, 1, 3, 6, and 12 months.

RESULTS

A total of 12 consecutive patients were recruited into the study. All had macula-on RDs and normal OCTs at onset. There were no operative or postoperative complications. Retinal reattachment was achieved in all cases within 24 h postoperatively. At 1 month six of 12 patients (50%) showed foveal detachment on OCT, which was invisible on clinical examination. At 3 months, the foveal detachment persisted in four (33%) of these patients. In these cases the foveal detachment persisted at 6 months follow-up, however, a reduction in subfoveal fluid was noted. All cases had foveal reattachment by 12 months postoperatively. Visual acuity was closely correlated to the presence of foveal attachment.

DISCUSSION

A high proportion of patients with successful retinal reattachment surgery had foveal detachments postoperatively. This phenomenon was associated with reduced visual acuity. The aetiology of this occurrence is unknown and warrants further investigation as there is the potential of a long-term effect on vision.

Intravitreal triamcinolone for diffuse diabetic macular oedema

AIM

To evaluate the efficacy of intravitreal triamcinolone (IVTA) for the treatment of diffuse diabetic macular oedema (DME) refractory to conventional argon macular laser therapy.

METHODS

A prospective, consecutive, and noncomparative case series was undertaken involving 38 eyes of 38 patients with refractory DME. Triamcinolone acetonide (4 mg) in 0.1 ml was injected intravitreally. LogMar visual acuity (VA) and macular thickness measured by ocular coherence tomography (OCT) were assessed preoperatively and postoperatively at 1, 3, and 6 months.

RESULTS

All patients completed 6 months of follow up. VA (mean+/-SD) improved from 0.905+/-0.23 to 0.605+/-0.28, 0.555+/-0.29, and 0.730+/-0.30 at 1, 3, and 6 months, respectively. Macular thickness baseline (mean+/-SD) on OCT was 418.7+/-104.2 microm and this decreased to 276.9+/-72.6 microm, 250.6+/-53.1 microm, and 308.8+/-87.3 microm at 1, 3, and 6 months, respectively.

CONCLUSIONS

IVTA may be a potential temporary treatment for refractory DME. It is effective in decreasing macular thickness and improving VA but the effect lasts approximately for 6 months in the majority of patients. Further investigations are required to establish the safety of IVTA for the treatment of DME.