Surgical Management and Techniques.

Technical advancements have substantially extended the indications for surgery in diabetic retinopathy (DR) during the last 40 years, from the traditional indications including non-clearing vitreous hemorrhage, traction retinal detachment (RD), and traction-rhegmatogenous RD, to epiretinal membrane (ERM), vitreomacular traction, diffuse macular edema, neovascular glaucoma, and anterior hyaloid fibrovascular proliferation. The goals of vitreoretinal surgery in DR are multiple: clearing media opacities, release of traction (anteroposterior and/or tangential), segmentation and/or removal of traction bands, peeling of ERMs, hemostasis, laser photocoagulation, and tamponade of retinal breaks with gas or silicone oil. The best management is achieved with integrated care provided by physicians with expertise in medical management of diabetes and surgical care of DR. In this chapter, the indications for surgery, preoperative considerations, surgical techniques, and complications, together with their management, will be discussed.

Sudden visual loss after cardiac resynchronization therapy device implantation.

PURPOSE: To report a case of sudden decrease in visual acuity possibly due to a cardiogenic embolism in a patient who underwent cardiac resynchronization therapy (CRT) device implantation. METHODS: A 62-year-old man with severe left ventricular systolic dysfunction and a left bundle branch block was referred to our department because of a sudden decrease in visual acuity. Nine days earlier, he had undergone cardiac transapical implantation of a CRT device, which was followed, 2 days later, by an inflammatory reaction. The patient underwent several general and ophthalmologic examinations, including multimodal imaging. RESULTS: At presentation, right eye (RE) best-corrected visual acuity (BCVA) was counting fingers and RE pupil was hyporeactive. Fundus examination revealed white-centered hemorrhagic dots suggestive of Roth spots. Fluorescein angiography showed delay in vascular perfusion during early stage, late hyperfluorescence of the macula and optic disk, and peripheral perivascular leakage. The first visual field test showed complete loss of vision RE and a normal left eye. Due to suspected giant cell arteritis, temporal artery biopsy was performed. Thirty minutes after the procedure, an ischemic stroke with right hemisyndrome and aphasia occurred. The RE BCVA worsened to hands motion. Four months later, RE BCVA did not improve, despite improvement in fluorescein angiography inflammatory sign. CONCLUSIONS: We report a possible cardiogenic embolism secondary to undiagnosed infective endocarditis causing monocular visual loss after CRT device implantation. It remains unclear how the embolus caused severe functional damage without altering the retinal anatomical structure.

Macular dysfunction is common in both type 1 and type 2 diabetic patients without macular edema.

PURPOSE: To study retinal function in asymptomatic Type 1 and Type 2 diabetic patients with nonproliferative diabetic retinopathy (NPDR) and no clinical signs of diabetic macular edema. METHODS: Thirty-six consecutive Type 1 and Type 2 diabetic patients with nonproliferative diabetic retinopathy and no diabetic macular edema and 28 healthy controls underwent a complete ophthalmologic examination, including spectral domain optical coherence tomography and microperimetry. RESULTS: Seventy-one eyes (17 patients with Type 1 and 19 with Type 2 diabetes) were tested, and data from 36 (17 Type 1 and 19 Type 2) eyes were analyzed. Mean best-corrected visual acuity was 0.00 ± 0.01 logMAR and 0.00 ± 0.02 logMAR for Type 1 and Type 2 diabetic patients, respectively (P = 0.075). Mean central foveal thickness was 234.5 ± 13.7 µm and 256.3 ± 12.7 µm for Type 1 and Type 2 diabetic patients, respectively (P = 0.04); the central foveal thickness was statistically different compared with the control groups (P = 0.04 and P = 0.01, respectively). Mean retinal sensitivity was 18.9 ± 0.5 dB and 17.7 ± 0.4 dB for Type 1 and Type 2 diabetic patients, respectively; it was statistically different compared with control groups (P < 0.0001 and P < 0.0001, respectively). CONCLUSION: We demonstrated a significantly reduced sensitivity in both nonproliferative diabetic retinopathy groups without diabetic macular edema compared with healthy controls; this reduction was greater in Type 2 diabetic patients. Central foveal thickness was increased in all diabetic patients compared with healthy controls, despite the absence of diabetic macular edema.

Influence of intraocular tamponade on unintentional retinal displacement after vitrectomy for rhegmatogenous retinal detachment.

PURPOSE: To investigate the relationship between type of intraocular tamponade and unintentional retinal displacement after vitrectomy for rhegmatogenous retinal detachment. METHODS: Twenty-three eyes of 23 consecutive patients affected by rhegmatogenous retinal detachment underwent 3-port pars plana vitrectomy with gas (C3F8) or silicone oil (polydimethylsiloxane) tamponade. Ophthalmologic examination and fundus autofluorescence were performed before surgery (baseline) and at the 7-day, 1-month, and 3-month postoperative visits. Macula sparing rhegmatogenous retinal detachment underwent fixation test (with microperimetry) at baseline and at the 7-day and 1-month follow-up examinations. RESULTS: Fundus autofluorescence revealed postoperative retinal displacement in 12 of the 23 eyes (52.2%). Occurrence of retinal displacement was higher in eyes with gas tamponade (10 of 14 eyes; 71.4%) compared with eyes with silicone oil (2 of 9 eyes; 22.2%) (P = 0.036). Retina shifted downward in all eyes with C3F8 and upward in all eyes with polydimethylsiloxane. Baseline and follow-up macular fixation was tested in 10 macula-on cases. In all cases, a shift of mean fixation point was present at the 7-day postoperative examination, with a partial return toward the baseline mean fixation point at the 1-month follow-up examination. CONCLUSION: In eyes with rhegmatogenous retinal detachment treated with vitrectomy and gas or silicone oil tamponade, retinal displacement may occur despite successful reattachment. Type of intraocular tamponade seems to influence the occurrence of retinal dislocation and its direction.

Macular micropseudocysts in early stages of diabetic retinopathy.

PURPOSE: To identify by noninvasive means early retinal abnormalities that may predict diabetic macular edema. METHODS: The authors analyzed retrospectively data from consecutive patients with Type 1 (n = 16) or Type 2 (n = 23) diabetes who presented for routine follow-up of early retinopathy, had no clinical signs or symptoms of diabetic macular edema, and were evaluated with spectral-domain optical coherence tomography. Age- and gender-matched nondiabetic subjects provided normative data. RESULTS: Spectral-domain optical coherence tomography revealed in the macular region of diabetic patients small hyporeflective areas (median diameter, 55 µm) contained within discrete retinal layers that we named micropseudocysts (MPCs). Micropseudocysts are associated with vascular leakage. The patients showing MPCs had more frequently systemic hypertension and increased central foveal thickness than those without MPCs. The association with increased central foveal thickness was only in the patients with Type 2 diabetes. CONCLUSION: Macular MPCs in patients with mild diabetic retinopathy appear to reflect leakage and can precede macular thickening. The association of MPCs with increased central foveal thickness in patients with Type 2 diabetes, but not in patients with Type 1 diabetes, points to a greater tendency to retinal fluid accumulation in patients with Type 2 diabetes. Studies in larger cohorts will determine the usefulness of MPCs in strategies to abort diabetic macular edema.

Intrasurgical plasmin enzyme in diabetic macular edema.

PURPOSE: To evaluate in a prospective study the efficacy of intrasurgical autologous plasmin enzyme (APE) in producing posterior vitreous detachment. DESIGN: Consecutive, interventional case series. METHODS: A group of 12 eyes of 11 patients with diabetic macular edema secondary to posterior vitreous cortex contraction was considered. A quantity of 0.1- to 0.2-ml containing 0.8 to 1.2 IU of APE prepared by our Coagulation Service was injected into the vitreous body 25 minutes before surgery. The efficacy of the APE was subjectively evaluated. A control group of 10 eyes with the same clinical characteristics underwent the same surgery without APE injection. Complete eye examinations, including optical coherence tomography, were performed on all patients before surgery and during the 1-year follow-up period. RESULTS: During surgery in the APE-treated group, the posterior vitreous cortex was judged adherent in three cases, partially detached in six cases, and totally detached in three cases. In two cases a complete collapse of the vitreous body was observed. During surgery in the non-APE-treated group, the posterior vitreous cortex was judged still adherent in nine of 10 eyes and partially detached in 1 eye. Comparing the postoperative results between the APE-treated group and the non-APE-treated group, we found no significant differences in final postoperative retinal thickness (P = .2552), whereas we found a significant difference in final visual acuity (P = .0121). CONCLUSIONS: Autologous plasmin enzyme was useful in inducing a pharmacologic posterior vitreous detachment and in facilitating surgery. It did not seem to interfere with the final retinal thickness, and it ameliorates the final visual acuity.