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.

Microcirculation at optic disc rim is correlated with visual field defects in cases of anterior ischaemic optic neuropathy

We report two cases of anterior ischaemic optic neuropathy in whom tissue blood flow at the disc rim was correlated with the visual field defect. Tissue blood flow of each eye was evaluated with Heidelberg retina flowmeter. Both cases experienced acute visual loss and an altitudinal hemianopsia associated with optic disc oedema in the affected eye. In each case, the tissue blood flow at the affected (upper or lower half) disc rim corresponding to visual field deficit was reduced compared with that at the opposite-sided half disc rim in the affected eye and with the corresponding area in the fellow eye. The reduction of blood flow in the affected half disc rim associated with the visual field defect demonstrated that retina flowmetry can detect differences in tissue blood flow between superior and inferior sectional disc rim areas as well as between eyes non-invasively.

Consequences of verteporfin photodynamic therapy on choroidal neovascular membranes

OBJECTIVE

To examine the impact of photodynamic therapy (PDT) on angiogenesis in human choroidal neovascular membranes with respect to vascular endothelial growth factor (VEGF) expression, proliferation, and vascularization.

METHODS

Retrospective review of an interventional case series of 50 patients (50 eyes) who underwent removal of choroidal neovascular membranes. Choroidal neovascularization was secondary to age-related macular degeneration. Twenty patients were treated with PDT 3 to 655 days before surgery. Choroidal neovascular membranes were stained for CD34, CD105, Ki-67, cytokeratin 18, and VEGF. Thirty choroidal neovascular membranes secondary to age-related macular degeneration without previous treatment were used as controls.

RESULTS

Specimens without pretreatment disclosed varying degrees of vascularization, proliferative activity, and VEGF expression by different cells. Specimens treated with PDT 3 days earlier showed mostly occluded vessels, damaged endothelial cells, and low proliferative activity. In contrast, specimens excised at later time points after PDT were highly vascularized and proliferating. This chronology was associated with an impressive VEGF immunoreactivity unique to retinal pigment epithelial cells shortly after PDT that also shifted to other cells at later time points.

CONCLUSIONS

Photodynamic therapy induces selective vascular damage in choroidal neovascular membranes. The effectiveness and selectivity of this treatment, however, seem to be jeopardized by a rebound effect initiated by enhanced VEGF expression in retinal pigment epithelial cells.

Scotopic threshold responses to infrared irradiation in cats

Infrared (IR) irradiation is frequently used in ophthalmological diagnosis and treatment. It has been used to selectively stimulate photodiode-based retinal prostheses to prove their function. Data concerning the natural IR-sensitivity of the retina are contradictory. In our experiments in dark-adapted cats an IR-laser (826 nm) and IR emitting diodes (875 nm) elicited clear scotopic threshold responses. Comparison of the two lasers (IR and a visible laser at 670 nm) using Lambs template and our experimental data revealed very similar differences in retinal sensitivity (4.28 and 3.94+/-0.29 log units, respectively). The fact that the cat retina is sensitive to IR-irradiation under certain conditions has important implications in interpreting the results from retinal prostheses and rewards further attention in its use in many ophthalmological applications.

Subjective visual sensation during vitrectomy under retrobulbar anesthesia

PURPOSE

To report a precise illustrated image of patient's view during vitrectomy.

DESIGN

Interventional case report.

METHODS

A 56-year-old male with cystoid macular edema (CME) associated with epiretinal membrane underwent vitrectomy. The patient seemed to find gratification in being operated on because he was able to see what was going on. He was a professional artist in computer graphics, and he drew three different pictures depending on the surgical procedures.

RESULTS

These pictures depicted the moving of pasty, whirling fluid during core vitrectomy, numerous black or gray spots like snowflakes by intravitrealy injected crystals of triamcinolone acetonide, and a sharp tapered instrument coming into the center and membrane-like material being peeled off.

CONCLUSIONS

Patients may see a precise shape in a constant size, scale, and detailed movement as well, focused on the retina without described optics. Further investigation will be required to determine this mechanism.

Progression rate of ALSFRS-R at time of diagnosis predicts survival time in ALS

The authors calculated the progression rate (DeltaFS) using the total revised ALS Functional Rating Scale (ALSFRS-R) and symptom duration at diagnosis in 82 Japanese patients with ALS. Survival (death or tracheostomy) differed significantly with the DeltaFS and postdiagnostic period according to log-rank testing, but Cox proportional hazards modeling revealed no strong association between total ALSFRS-R and mortality, suggesting that the DeltaFS provides an additional predictive index beyond ALSFRS-R alone.

Detecting vitreomacular adhesions in eyes with asteroid hyalosis with triamcinolone acetonide

BACKGROUND

To report the incidence of posterior vitreous detachments (PVDs) and the surgical results of vitrectomy with intravitreal triamcinolone acetonide (TA) to detect vitreomacular adhesions in eyes with asteroid hyalosis (AH).

METHODS

Ten eyes of nine patients with AH underwent vitrectomy, six eyes with TA and four without TA. The presence of a PVD was determined preoperatively by ultrasound echography (USE) and intraoperatively by microscopic observations. The postoperative best-corrected visual acuities (BCVA) were evaluated.

RESULTS

The BCVA was improved by >2 Snellen lines in nine eyes and maintained at 20/20 with symptomatic improvements in the other eye. A vitreomacular adhesion was clearly seen during TA-assisted vitrectomy, and none was seen when TA was not used, even though preoperative USE showed an incomplete PVD in all eyes. The BCVA was not significantly better in eyes with TA-assisted vitrectomy than without TA-assisted vitrectomy. In one eye with vitrectomy without TA, a second surgery was required for a persistent cystoid macular edema and an epiretinal membrane. The BCVA and the edema in this eye improved after removing the epiretinal membrane.

CONCLUSIONS

All (ten) of the eyes with AH were found to have a vitreomacular adhesion by preoperative USE and intraoperative microscopic observations. The residual vitreous over the macula is more easily detected and removed after intravitreally injected TA, but the visual acuities were not significantly different from eyes without TA.

Toxicity study of erucylphosphocholine in a rat model

PURPOSE

To investigate the effect of intraocular erucylphosphocholine (ErPC) on the retina, the retinal pigment epithelium (RPE), and the choroid in an in vivo rat model.

METHODS

Adult male Brown Norway rats were injected intravitreally with ErPC dissolved in balanced salt solution (BSS) at a final concentration of 10 or 100 microM with BSS serving as control. Adverse effects on the anterior and posterior segment were assessed by slit-lamp biomicroscopy and ophthalmoscopy. Retinal toxicity was assessed by electroretinography (ERG), retinal ganglion cell (RGC) quantification, and histology 7 days after intravitreal administration of ErPC.

RESULTS

There was neither a statistically significant difference in the clinical examination nor in the ERG waves of treated versus control rats 7 days after intravitreal administration of ErPC. Correspondingly, the number of RGC after BSS injection did not differ significantly from ErPC-injected animals. Histologic sections of the posterior segment of 10 and 100 microM ErPC-injected rats did not show any signs of retinal toxicity. Electron microscopy did not display a difference between the 10 microM and the control group. Only the 100 microM-injected animals showed a discrete irregularity of the Müller cell and the retinal ganglion cell cytoplasm at the ultrastructural level.

CONCLUSIONS

ErPC can safely be injected into the vitreous of adult rats at a concentration of 10 microM without any retinal toxicity. Even a 10-fold increase in ErPC concentration leads only to a discrete cytoplasmic irregularity of the innermost retinal layers.

Decreased blood flow at neuroretinal rim of optic nerve head corresponds with visual field deficit in eyes with normal tension glaucoma

PURPOSE

To determine the relationship between the blood flow parameters of the optic disc rim and the glaucomatous visual field changes.

DESIGN

Observational cross-sectional study.

METHODS

Tissue blood flow in the neuroretinal rim within the optic disc was determined with the Heidelberg retina flowmeter(HRF) in 54 eyes of 54 patients with normal tension glaucoma (NTG). Patients were selected whose visual field defects were confined to either the superior or inferior hemifield. Blood flow measurements were made in a 10 degrees x 2.5 degrees area of the superior and inferior neuroretinal rim within the optic disc. The mean blood flow (MBF) was calculated by the automatic full-field perfusion image analyzer program, and the ratio of the MBF in the superior to the inferior rim areas (the S/I ratio) was calculated from the same HRF image in order to minimize the variation of measurement condition.

RESULTS

Inferior rim blood flow is less than superior rim blood flow in patients with superior hemifield defect, and superior rim blood flow is reduced compared to inferior in patients with inferior hemifield defect. The mean S/I ratios of the MBF in the patients with superior hemifield defect (1.46, n=37) was significantly higher than that in the patients with inferior hemifield defect (0.79, n=17; P<0.0001, Mann-Whitney U-test).

CONCLUSIONS

The blood flow in the neuroretinal rim was found to correspond to the regional visual field defect in eyes with NTG. Reductions in flow were associated with reductions in function.

Intraocular lens implantation after atopic cataract surgery decreases incidence of postoperative retinal detachment

PURPOSE

To investigate the efficacy of intraocular lens (IOL) implantation in reducing the incidence of postoperative retinal detachment after cataract surgery in patients with atopic dermatitis.

DESIGN

Retrospective review.

PARTICIPANTS

One hundred sixty-nine eyes of 126 patients who underwent cataract surgery for atopic cataract were followed for more than 1 year. None of the eyes previously had a retinal detachment or retinal detachment surgery.

METHODS

The eyes were divided into 132 eyes of 95 patients with an IOL implantation (IOL group) and 37 eyes of 31 patients without an IOL implantation (aphakia group). The postoperative visual acuity and incidence of postoperative retinal detachment were compared between the 2 groups. The effects of the location of the causative retinal breaks, intraoperative posterior capsule rupture, and postoperative posterior capsulotomy on the incidence of retinal detachments were evaluated.

MAIN OUTCOME MEASURES

The postoperative corrected visual acuity, incidence of postoperative retinal detachment, and influence of intraoperative posterior capsule rupture on the retinal detachment.

RESULTS

The final visual acuity was better than or equal to 20/20 in 128 eyes (97.0%) of the IOL group and in 29 eyes (78.4%) of the aphakia group (P = 0.0007). Retinal detachment after an uncomplicated cataract surgery occurred in 3 eyes (2.3%) of the IOL group and in 8 eyes (25.8%) of the aphakia group (P<0.0001, Mantel-Cox). Two of 3 eyes (66.7%) in the IOL group and 1 of 8 eyes (16.7%) in the aphakia group that later developed a retinal detachment had an intraoperative posterior capsule rupture. Posterior capsulotomy by yttrium-aluminum-garnet laser did not seem to alter the incidence of postoperative retinal detachment in either the IOL (2.0%) or the aphakia group (25.0%).

CONCLUSIONS

The rate of postoperative retinal detachment in eyes with IOL and no intraoperative posterior capsule rupture seems to be low. Intraocular lens implantation with capsular bag fixation may reduce the incidence of postoperative retinal detachment triggered by lens surgery for atopic cataract.

Effect of topical unoprostone isopropyl on optic nerve head circulation in controls and in normal-tension glaucoma patients

PURPOSE

To evaluate the effect of unoprostone isopropyl on microcirculation in the optic nerve head (ONH) of controls and patients with normal-tension glaucoma (NTG).

METHODS

Thirty healthy volunteers were randomly placed in a placebo group or a control group. For ten NTG patients, one eye was selected to receive the placebo drops and the contralateral eye received the unoprostone in a masked fashion. In both studies, the intraocular pressure (IOP) and the parameters of the blood hemodynamics of the ONH were obtained before and at 1 and 2 h after the instillation. Blood flow measurements were made with a scanning laser Doppler flowmeter.

RESULTS

In both control subjects and NTG patients, the changes in the IOPs after the instillation of either unoprostone or the placebo were not significant because almost all of the NTG patients had IOPs lower than 15 mmHg. Although the hemodynamic parameters were not significantly changed in the placebo-treated eyes of the controls, the eyes of the controls treated with unoprostone had mean blood velocity and flow values that were significantly higher than the baseline values 1 and 2 h after instillation (P < 0.01). The velocity values of the controls treated with unoprostone were significantly higher than in those controls receiving the placebo at 2 h postinstillation (P = 0.027). The values for the three circulation parameters (volume, velocity, flow) were significantly higher than the baseline values after instillation in the eyes of the NTG patients treated with unoprostone (P < 0.05). In contrast, none of these parameters was significantly different from the baseline in the eyes of NTG patients treated with placebo.

CONCLUSIONS

These results showed that unoprostone significantly increased microcirculation in the ONH in control subjects and in NTG patients without reducing the IOP significantly.

Suppression of Ocular Inflammation in Endotoxin-Induced Uveitis by Blocking the Angiotensin II Type 1 Receptor

PURPOSE

To examine whether the angiotensin II type 1 receptor (AT1-R) signaling plays a role in ocular inflammation in endotoxin-induced uveitis (EIU).

METHODS

EIU was induced in C57BL/6 mice by a single intraperitoneal injection of 150 mug lipopolysaccharide (LPS). Tissue localization, mRNA expression, and protein levels of AT1-R in murine retinas were examined by immunohistochemistry, RT-PCR, and Western blot analyses, respectively. Telmisartan, an AT1-R antagonist widely used as an antihypertensive agent, was administered intraperitoneally at a dose of 10 mg/kg daily for 5 days until the injection of LPS. Twenty-four hours after administration, leukocyte adhesion to the retinal vasculature was evaluated with a concanavalin A lectin perfusion-labeling technique. Retinal mRNA and protein levels of intercellular adhesion molecule (ICAM)-1 were examined by RT-PCR and ELISA, respectively. Protein concentration and inflammatory cells in the aqueous humor were also measured.

RESULTS

Retinal vessels were positive for AT1-R. In mice with EIU, retinal AT1-R mRNA and protein levels were significantly increased when compared to the normal control. EIU animals also showed significant increases in the number of inflammatory cells infiltrating the anterior chamber and adhering to the retinal vessels and in retinal ICAM-1 levels. Administration of telmisartan to EIU mice resulted in significant suppression of retinal ICAM-1 expression and leukocyte adhesion and infiltration compared with vehicle treatment. Protein concentration in the aqueous humor of telmisartan-treated EIU mice tended to be lower than that of vehicle-treated EIU mice, but the difference was not statistically significant.

CONCLUSIONS

AT1-R signaling blockade inhibited retinal ICAM-1 upregulation and leukocyte adhesion and infiltration in the EIU model. These results suggest the potential use of an AT1-R antagonist as a therapeutic agent to reduce ocular inflammation.

Complete nucleotide sequence of the new potexvirus "Alstroemeria virus X". Brief report

A flexuous virus was isolated in Japan from an alstroemeria plant showing mosaic symptoms. The virus had a broad host range but had systemically latent infectivity in alstroemeria. The virus was assigned to the genus Potexvirus based on morphology and physical properties and on an analysis of the complete nucleotide sequence. The genomic RNA of the virus was 7,009 nucleotides in length, excluding the 3'-terminal poly (A) tail. It contained five open reading frames (ORFs), which was consistent with other members of the genus Potexvirus. Although nucleotide sequences of the ORFs differ from previously reported potexviruses, a phylogenetic analysis placed it phylogenetically close to Narcissus mosaic virus and Scallion virus X. Therefore, we propose that this virus should be designated as Alstroemeria virus X (AlsVX).

Massive bilateral vitreoretinal hemorrhage in patient with chronic refractory idiopathic thrombocytopenic purpura

BACKGROUND

We describe a patient with chronic, refractory idiopathic thrombocytopenic purpura (ITP) who developed massive vitreoretinal hemorrhages in both eyes.

METHODS

A 49-year-old woman complained of an acute decrease of vision, and ophthalmoscopy revealed bilateral preretinal and subretinal hemorrhages around the optic disc. Her platelet counts were less than 5000/mul in spite of repetitive administration of corticosteroids and immunoglobulins with splenectomy for the chronic refractory ITP. One month later, she developed massive vitreoretinal hemorrhages bilaterally, and vision decreased to hand-motion.

RESULTS

Vitrectomy was performed on both eyes after medical treatment to increase platelet counts. The intraretinal hemorrhages were absorbed from the area around the disc and vision recovered to 20/100 in the right eye and 20/2000 in the left after one month.

CONCLUSION

Massive vitreoretinal hemorrhages can develop in patients with chronic refractory ITP, and vitrectomy can be beneficial for this condition.

Clinical manifestations of chronic inflammatory demyelinating polyneuropathy with anti-cardiolipin antibodies

OBJECTIVE

Chronic inflammatory demyelinating polyneuropathy (CIDP) is an autoimmune syndrome where certain autoantibodies define clinicopathologic subgroups. In the present study, serum anti-cardiolipin antibodies (aCL) were evaluated.

MATERIALS AND METHODS

We investigated aCL in sera from 21 patients diagnosed with CIDP in our hospital between 1991 and 2001. The four CIDP patients with aCL (aCL+) were compared with 17 patients without aCL (aCL-).

RESULTS

All aCL+ patients displayed sensory-motor polyneuropathy, with severity and distribution of weakness resembling those in aCL- patients. Anti-nuclear antibody titer of aCL+ patients were significantly higher than those in aCL- patients. None of aCL+ patients presented clinical manifestations of primary anti-phospholipid syndrome (APS), such as thromboses or recurrent abortion. Although the aCL+ patients were older and had more complications and more severe pathologic features than aCL- patients, they responded well to steroid pulse or intravenous immunoglobulin.

CONCLUSION

The aCL in CIDP apparently differ from 'autoimmune' aCL in APS, instead being among the autoantibodies pathologically involved in CIDP subgroups.

Selective Suppression of Pathologic, but Not Physiologic, Retinal Neovascularization by Blocking the Angiotensin II Type 1 Receptor

PURPOSE

To investigate the anti-inflammatory and anti-angiogenic effects of telmisartan, an angiotensin II type 1 receptor (AT1-R) antagonist, on ischemia-induced retinal neovascularization.

METHODS

C57BL/6 neonatal mice were reared in an 80% concentration of oxygen from postnatal day (P)7 to P12, followed by room-air breathing until P17, to induce ischemia-initiated retinal neovascularization (i.e., a murine model of ischemic retinopathy). Tissue localization of AT1-R was examined by immunohistochemistry for murine retinal wholemounts and human fibrovascular tissues excised at vitrectomy for proliferative diabetic retinopathy. Animals received intraperitoneal injection of telmisartan or vehicle. A concanavalin A lectin perfusion-labeling technique was used to evaluate the areas of physiological and pathologic retinal new vessels and the number of leukocytes adhering to the vasculature. Retinal mRNA and protein levels of intercellular adhesion molecule (ICAM)-1, vascular endothelial growth factor receptor (VEGFR)-1, and VEGFR-2 were examined by RT-PCR and ELISA.

RESULTS

Vessels in human fibrovascular tissues and the murine retinas were positive for AT1-R. Pathologic (P < 0.01), but not physiologic (P > 0.05), retinal neovascularization was significantly suppressed in telmisartan-treated mice compared with vehicle-treated animals. The number of adherent leukocytes (P < 0.01) was also significantly reduced, together with retinal ICAM-1 levels (P < 0.01) in the telmisartan-treated group compared with the control group. No significant difference was detected in retinal VEGFR-2 levels between the two groups, whereas retinal VEGFR-1 levels in the telmisartan-treated group were significantly (P < 0.05) lower than in the vehicle-treated group.

CONCLUSIONS

The present findings suggest that the AT1-R signaling blockade leads to the selective suppression of pathologic, but not physiological, retinal neovascularization through the inhibition of the inflammatory processes related to pathologic neovascularization.

In vivo assessment of subretinally implanted microphotodiode arrays in cats by optical coherence tomography and fluorescein angiography

BACKGROUND

Following multiple promising investigations into restoration of vision in degenerative retinal disease by implantation of a sub- or epiretinal prosthesis, the step to clinical use in humans is impending. In this study we intended to establish optical coherence tomography (OCT) and fluorescein angiography (FA) first in research animals for noninvasive assessment of the condition of the posterior pole of eyes after intraocular implant surgery.

METHODS

Three adult cats that had undergone subretinal implant surgery were evaluated by OCT and FA between 1 and 470 days postoperatively. Eight adult cats served as control. In addition histology was performed.

RESULTS

In all three cats OCT demonstrated stable positioning of the implants in the subretinal space during the complete examination period. Transient retinal edema was found in the early postoperative period but decreased during follow-up. The retina over the implants was well attached at all times in cats 1 and 2; however, in cat 3 localized retinal detachment was demonstrated. FA showed intact retinal vasculature over the subretinal implant in high detail without interference from choroidal background fluorescence.

CONCLUSIONS

OCT and FA have been fruitfully applied to cats to assess the morphological and circulatory conditions of the neuroretina and of its interface with the subretinal implant. The techniques may therefore provide a tool for objective, noninvasive in vivo evaluation of eyes that have undergone subretinal implant surgery, both in research animals and in humans.

Retinal blood flow in the macular area before and after scleral buckling procedures for rhegmatogenous retinal detachment without macular involvement

PURPOSE

To investigate retinal microcirculation changes in patients with rhegmatogenous retinal detachment (RRD).

METHODS

The tissue blood flow in the macular area was measured in 28 patients with RRD without macular involvement by scanning laser Doppler flowmetry before and after scleral buckling procedures. The mean blood flow (MBF) was calculated by the automatic full-field analysis program. The MBF ratios of the affected eye to the fellow eye (a/f ratio) in patients were compared with those of the right eye to the left eye (R/L ratio) in the control subjects.

RESULTS

The mean preoperative a/f ratio in the patients (0.81 +/- 0.11) was lower than the mean R/L ratio in the control subjects (1.02 +/- 0.11, P < 0.0001) and correlated with the extent of RRD (P < 0.05). The mean a/f ratio tended to decrease 2 weeks after surgery (0.72 +/- 0.09) and recovered to an almost normal level after 1 month (0.96 +/- 0.09). The blood-flow change was not influenced by the type of buckling.

CONCLUSIONS

The retinal microcirculation in the macular area was disturbed in RRD patients without macular involvement. It correlated with the extent of the RRD, and subsided 1 month after successful scleral buckling procedures.

Successful treatment of subfoveal choroidal neovascularization associated with combined hamartoma of the retina and retinal pigment epithelium

PURPOSE

To describe a patient with subfoveal choroidal neovascularization (CNV) associated with combined hamartoma of the retina and retinal pigment epithelium (CHRRPE), treated successfully by submacular surgery.

DESIGN

Interventional case report.

METHODS

A 12-year-old girl was referred to our clinic for evaluation. Visual acuity was 20/30 in the affected left eye. Ophthalmoscopy disclosed juxtapapillary CHRRPE and subfoveal pigmented CNV. Vitreous surgery was carried out because of visual deterioration to 20/60.

RESULTS

The posterior vitreous was strongly attached to glial tissue at the superior margin of the optic disk in the CHRRPE region. The CNV, which was not connected with the CHRRPE, was carefully removed, resulting in visual improvement to 20/20 5 months after surgery. Histologically, the excised membrane showed fibroblast-rich cellular component and a type 2 configuration.

CONCLUSION

Submacular surgery can be effective for the treatment of secondary CNV associated with CHRRPE.