HEADS-UP SURGERY FOR VITREORETINAL PROCEDURES: An Experimental and Clinical Study.

PURPOSE: To investigate the feasibility of performing vitrectomies while viewing a three-dimensional image on a large display in a heads-up position. METHODS: Twenty volunteers were compared performing meticulous tasks using the heads-up and the traditional method. Some optical parameters, resolution and depth of field, were measured, and the possibilities of digital image processing were investigated. In addition, routine use of the heads-up method for >400 vitrectomies over 8 months was retrospectively analyzed. RESULTS: Of note, 91.7% of the volunteers preferred the ergonomics of the heads-up technique. The two methods were judged to be similar regarding speed and ease of microscopic manipulations and sharpness of image. Significantly fewer mistakes were made with the heads-up method. The measured resolution of the eyepieces was approximately twice that of the three-dimensional display, whereas depth of the field was about equal. Electronic amplification of the camera's signal resulted in increased image brightness, allowing use of reduced endoillumination levels. In clinical routine, better ergonomics, digital image processing, and use of a large display are found to be major advantages. CONCLUSION: The heads-up method is well suited for vitreoretinal surgery. With further technical improvements, the procedure should soon find widespread use.

Early effects of intravitreal triamcinolone acetonide on inflammation and proliferation in human choroidal neovascularization.

OBJECTIVE: To evaluate the early effects of triamcinolone acetonide (TA) on inflammation, proliferation, and vascular endothelial growth factor (VEGF) in human choroidal neovascularization (CNV). METHODS: Retrospective review of an interventional case series of 29 patients who underwent macular translocation. Fourteen CNV membranes without previous therapy (control CNV group) and 4 CNV membranes excised 3 days after photodynamic therapy (PDT CNV group) comprised the control groups. Eleven patients were treated with intravitreal TA (TA CNV group; n = 5) or PDT and TA combined (PDT+TA CNV group; n = 6) 3 to 9 days preoperatively. The CNV membranes were stained for cytokeratin 18, CD34, VEGF, intercellular adhesion molecule-1 (ICAM-1), E-selectin, CD68, CD45, Ki-67, and Thy-1. RESULTS: Treatment with TA and PDT+TA resulted in increased immunostaining of ICAM-1 in endothelial cells and the stroma and a higher percentage of Thy-1 expression than controls. The density of macrophages was significantly increased in PDT+TA CNV membranes. Leukocyte density and proliferative activity were lower in TA and PDT+TA CNV membranes. The total VEGF score was significantly increased in TA and PDT+TA CNV membranes compared with the control CNV membranes. Evidence of VEGF in the retinal pigment epithelium of PDT+TA CNV membranes was stronger than in control CNV membranes. CONCLUSIONS: Triamcinolone acetonide has no inhibitory effect on macrophage infiltration or ICAM-1, Thy-1, or VEGF expression in CNV membranes in the early term. The clinical benefits of TA are probably not based on pure antiinflammatory or VEGF-suppressing mechanisms.

New components of 'basal laminar deposits' in age-related macular degeneration.

Two new components of basal laminar deposit (BlamD) occurring in samples of submacular neovascular membranes surgically removed from patients with a wet (exudative) form of age-related macular degeneration are described. They are: (1) minute ribbon-like structures which occur singly and/or in a bunch and extend from the inner surface of the BlamD layer into the extracellular matrix (ECM) beneath the retinal pigment epithelium (RPE). The ribbons are composed of polarized molecules, aggregating in parallel, aligned transversally in register, morphologically similar to isolated collagen molecules of the short-chain type. Deeper in the BlamD but always close to its inner surface, aspects suggesting a transition between ribbons and (2) long-spacing collagen (LSC)-like aggregates characterized by periods bordered by a single dense band were observed. This band could arise from the globular domains of the polarized monomers, which assemble in parallel and display all their terminal extensions at the same end of each period resulting in the single dense band. The presence of ribbons and of LSC-like aggregates in the BlamD layer and the concomitant choroidal neovascularization (CNV) suggest that the events might be correlated. The newly formed vessels crossing Bruch's membrane and invading the BlamD layer could induce physicochemical changes in the ECM of the RPE, providing the required environmental conditions for the polymerization of collagen molecules into aggregates with the LSC-like pattern. With the deposition of new components, the thickness of BlamD increases and further impairs the supply of nutrients and oxygen, thus sustaining CNV.

Macular hole surgery with air tamponade and optical coherence tomography-based duration of face-down positioning.

PURPOSE: To evaluate the closure rate after macular hole surgery with air tamponade and face-down positioning whose duration is based on postoperative optical coherence tomography (OCT). METHODS: In a prospective study, data were gathered on 33 eyes of 33 consecutive patients undergoing macular hole surgery. Postoperatively, OCT images were obtained in a face-down position to minimize the interfering reflections created by the air bubble. The face-down positioning was ended as soon the OCT revealed closure of the hole. RESULTS: Opacity of the media in 8/33 eyes 24 hours postoperatively precluded OCT. In 18/33 eyes (54.5%), the hole was closed on OCT 24 hours postoperatively and in 25/33 (75.7%), 48 hours postoperatively. In 4/33 eyes (12.1%), the hole was judged to be open on OCT 24 hours postoperatively. Despite continued face-down positioning, the hole had closed on the third day postoperatively in only one of these four eyes. In two of the remaining three eyes, the macular hole could be closed by a second surgery which was performed 5 to 6 days after the first vitrectomy. Using OCT monitoring, more than half (54%) of our patients could quit the face-down position after 24 hours, 21% after 48 hours, and 24% after 3 days. CONCLUSION: Vitrectomy and air tamponade combined with 1- to 3-day face-down positioning produced an excellent rate of macular hole closure. Already on the first and second day postoperatively OCT on patients in a prone position enabled the monitoring of the progress of the macular hole closure through the air bubble. This method allows effective adjustment of the duration of face-down positioning based on OCT findings.

Effect of bevacizumab on inflammation and proliferation in human choroidal neovascularization.

OBJECTIVE: To evaluate the effect of bevacizumab (Avastin; Genentech, Inc, South San Francisco, California) on inflammation and proliferation in human choroidal neovascularization (CNV) secondary to age-related macular degeneration. METHODS: Retrospective review of interventional series of 38 patients who underwent choroidal neaovascular membrane (CNVM) extraction. Twenty-four patients received intravitreal bevacizumab 1 to 154 days preoperatively (bevacizumab CNV group). Fourteen patients received no preoperative therapy (control CNV group). The CNVM were stained for cytokeratin 18, CD68, CD45, intercellular adhesion molecule (ICAM)-1, E-selectin, Ki-67, Thy-1, and endostatin. RESULTS: No significant difference was detected in ICAM-1 and E-selectin expression between groups. The density of leukocytes in the bevacizumab CNV group (median, 271.61 cells/mm(2)) was higher than in the control CNV group (median, 116.87 cells/mm(2); P = .07), but without significance. Density of macrophages (median, 4661.95 cells/mm(2)), proliferative activity (median, 160.19 cells/mm(2)), and percentage of Thy-1-expressing vessels (median, 100%) were significantly higher in the bevacizumab CNV group than in the control CNV group (median, 882.66 cells/mm(2), P < .001; median, 34.34 cells/mm(2), P < .001; and median, 80%, P < .001, respectively). Endostatin immunoreactivity was considerably stronger in the retina pigment epithelium (RPE)-Bruch membrane complex (median, 3; range, 2-3; P < .001), and stroma (median, 3; range, 1-3; P < .001) of the bevacizumab CNV group than control CNV group (median, 1.5; range, 0-3 and median, 1; range, 0-3, respectively). CONCLUSIONS: Unexpectedly, CNVM from patients treated by bevacizumab are characterized by significantly high inflammatory and proliferative activity and enhanced endostatin expression. These characteristics need to be considered when protocols for combination therapies are established.

Early effects of triamcinolone on vascular endothelial growth factor and endostatin in human choroidal neovascularization.

OBJECTIVE: To evaluate the early effects of triamcinolone acetonide as monotherapy or as an adjuvant to ocular verteporfin photodynamic therapy (PDT) on angiogenesis in human choroidal neovascularization (CNV) secondary to age-related macular degeneration. METHODS: Retrospective review of an interventional series of 55 patients who underwent CNV extraction. Eleven patients were treated with intravitreal triamcinolone acetonide (4 mg) monotherapy (triamcinolone-treated CNV group [n = 5]) or with PDT-triamcinolone combination therapy (PDT-triamcinolone-treated CNV group [n = 6]) 3 to 9 days before surgery. Forty patients who underwent CNV extraction without previous therapy (control CNV group) and 4 patients who underwent CNV extraction 3 days after PDT (PDT CNV group) served as control subjects. The CNV samples were stained for CD34, endostatin, cytokeratin 18, and vascular endothelial growth factor (VEGF). RESULTS: Vascular endothelial growth factor expression was stronger in the PDT CNV samples (P < .001), triamcinolone CNV samples (P = .01), and PDT-triamcinolone CNV samples (P = .007) compared with the control CNV samples. There were no statistically significant differences in VEGF expression among the PDT CNV samples, triamcinolone CNV samples, and PDT-triamcinolone CNV samples. Endostatin expression was weaker in the PDT CNV samples than in the control CNV samples (P = .008). Endostatin expression was stronger in the triamcinolone CNV samples and the PDT-triamcinolone CNV samples compared with the control CNV samples (P = .001 and P < .001, respectively) and the PDT CNV samples (P < .001 for both). CONCLUSION: To some extent, triamcinolone monotherapy seems to exert its angiogenesis inhibitory effects on CNV by enhancing endostatin expression rather than by suppressing VEGF expression.

Influence of verteporfin photodynamic therapy on inflammation in human choroidal neovascular membranes secondary to age-related macular degeneration.

PURPOSE: To examine the short- and long-term consequences of verteporfin photodynamic therapy (PDT) on inflammation with regard to infiltration of macrophages and leukocytes and expression of thy-1 in human choroidal neovascularization membranes (CNV) secondary to age-related macular degeneration (AMD). METHODS: Retrospective review of an interventional case series of 43 patients who underwent removal of CNV. Twenty patients were treated with PDT 3 to 246 days preoperatively. Twenty-three CNV without previous treatment were used as control. CNV were stained for CD34, CD105, cytokeratin 18, Ki-67, thy-1, an endothelial cell glycoprotein known to be upregulated only by inflammatory cytokines, CD68 (macrophages), and CD45 (common leukocyte antigen). RESULTS: Specimens treated by PDT 3 days previously showed significantly reduced endothelial thy-1 expression (P = 0.008), leukocyte (P=0.04) and macrophage (P=0.0063) infiltration, and proliferative activity (P=0.02) compared to control CNV. Specimens at longer intervals after PDT, in contrast, disclosed a significantly increased expression of thy-1 (P=0.004), infiltration with leukocytes (P=0.044) and macrophages (P=0.01), and proliferative activity (P=0.03) compared to CNV excised 3 days after PDT. CONCLUSIONS: The rebound effect after PDT seems to be based on an inflammatory response that contributes to enhanced proliferation. These data support the need for an anti-inflammatory therapy as adjuvant to PDT.

Effect of verteporfin photodynamic therapy on endostatin and angiogenesis in human choroidal neovascular membranes.

AIM: To evaluate the effect of verteporfin photodynamic therapy (PDT) on endostatin with regard to expression of vascular endothelial growth factor (VEGF) in human choroidal neovascular membranes (CNVs) secondary to age-related macular degeneration. METHODS: A retrospective review of an interventional case series of 68 patients who underwent removal of CNV. 29 patients were treated with PDT 3-655 days before surgery. 39 CNVs without previous treatment were used as controls. CNVs were stained for CD34, CD105, Ki-67, cytokeratin 18, endostatin, E-selectin and VEGF. "Predominance score of VEGF over endostatin" (mean) was defined as the difference between VEGF and endostatin staining scores. RESULTS: In four CNVs treated by PDT 3 days previously, PS was significantly higher in the retinal pigment epithelium (mean = 2.5, p = 0.006) and stroma (mean = 2, p = 0.015) than in the control group (mean = 0). At longer post-PDT intervals, PS was significantly decreased in the retinal pigment epithelium (mean = 0, p = 0.019) and stroma (mean = 0, p = 0.015). Proliferative activity was high (p = 0.023), but mostly related to inflammatory cells. PDT did not influence E-selectin expression significantly. CONCLUSIONS: VEGF predominance over endostatin early after PDT might contribute to enhanced angiogenic activity associated with recurrences. Strategies upregulating or replacing endostatin early after PDT might increase the effectiveness of PDT.

Expression of VEGF and PEDF in choroidal neovascular membranes following verteporfin photodynamic therapy.

PURPOSE: To examine the impact of photodynamic therapy (PDT) on pigment epithelium derived factor (PEDF) expression in human choroidal neovascularization (CNV) membranes with regard to vascular endothelial growth factor (VEGF) expression. DESIGN: Interventional case series. METHODS: Retrospective review of interventional case series of 42 patients (42 eyes) who underwent removal of CNV. CNV was secondary to age-related macular degeneration (AMD) in all cases. Fifteen patients were treated with PDT, 3 to 246 days before surgery. CNV were stained for CD34, CD105, cytokeratin 18, VEGF, and PEDF. Twenty-seven CNV without previous treatment were used as control. RESULTS: Specimens without pretreatment disclosed varying degrees of vascularization, VEGF, and PEDF expression by different cells. Specimens treated by PDT, three days previously showed mostly occluded vessels lined with damaged endothelial cells (EC). In contrast, specimens excised at later time points after PDT were highly vascularized with healthy EC. This chronology was associated with an impressive VEGF immunoreactivity increased considerably in retinal pigment epithelial cells as well as significantly reduced PEDF expression in EC and stroma. CONCLUSIONS: PDT induces a selective vascular damage in CNV. The effectiveness of PDT, however, seems to be jeopardized by a rebound effect initiated by an enhanced VEGF and reduced PEDF expression in CNV.

Macular translocation in a patient with adult-onset foveomacular vitelliform dystrophy with light- and electron-microscopic observations on the surgically removed subfoveal tissue.

PURPOSE: To correlate the functional results of macular translocation (MT) in a patient suffering from an adult-onset foveomacular vitelliform dystrophy (AFVD) with the microscopic findings of the surgically removed subfoveal retinal pigment epithelium (RPE). METHODS: A 78-year-old woman with AFVD underwent MT with 360 degrees retinotomy 3-4 months after loss of reading ability. Most of the vitelliform material was lost during surgery; the subfoveal tissue was excised, fixed in aldehydes, postfixed in reduced OsO4 and embedded in epoxy resin. Semithin sections were stained with toluidine blue for light microscopy (LM) and thin sections with uranyl acetate and lead citrate for transmission electron microscopy (TEM). RESULTS: Postoperatively, the patient developed a retinal detachment complicated by proliferative vitreoretinopathy (PVR) requiring two additional vitreoretinal procedures before finally the silicone oil could be removed. Twenty-two months after MT the distance visual acuity was unchanged at 0.2; the near visual acuity had improved from less than 0.1 before MT to 0.4. The retina was completely attached. LM and TEM revealed serious alterations indicative of a breakdown of the outer layer of the retina. CONCLUSION: Through the present single case it is not possible to determine whether MT could be a therapeutic approach in patients with AFVD. The most important cause for the limited postoperative visual improvement seems to be a primary injury of the foveal function due to the AFVD. This is supported by the extensive subfoveal degeneration and necrosis affecting not only the RPE cells but also their basement membrane and the interposed basal laminar deposits.

Trypan blue staining in vitreoretinal surgery.

PURPOSE: To evaluate the efficacy of trypan blue for staining the internal limiting membrane (ILM) and epiretinal membranes (ERM) in vitreoretinal surgery. DESIGN: Prospective noncomparative case series. PARTICIPANTS: Fifty eyes of 50 patients with macular pucker (n = 22), macular hole (n = 18), or a combination (n = 2), proliferative vitreoretinopathy (n = 5), or diabetic retinopathy (n = 3). METHODS: Trypan blue 0.2% was used to stain the ILM or ERM during vitreoretinal surgery. MAIN OUTCOME MEASURES: The intraoperative visibility of the membranes was scored as poor, moderate, good, or excellent. RESULTS: The application of trypan blue onto the ILM or the ERM resulted in a useful bluish staining, facilitating the identification, delineation, and removal of the membranes in all surgeries. No residual staining or adverse effects related to the dye were observed. CONCLUSIONS: Trypan blue stains both ILM and ERM and might be an useful tool in vitreoretinal surgery.