Comparison of three techniques of foveal translocation in patients with subfoveal choroidal neovascularization resulting from age-related macular degeneration

PURPOSE

To report the results of three methods of foveal translocation in the presence of subfoveal choroidal neovascular membrane resulting from age-related macular degeneration.

METHODS

We treated 51 eyes of 51 consecutive patients with subfoveal choroidal neovascular membranes resulting from age-related macular degeneration with one of three techniques of foveal translocation surgery: foveal translocation with partial retinotomy (n = 6), limited translocation (n = 9), and translocation with 360-degree retinotomy (n = 36). All patients were followed for at least 6 months postoperatively. The size of the choroidal neovascular membrane and the amount of foveal displacement, the best-corrected visual acuity, and complications were recorded preoperatively and postoperatively.

RESULTS

The mean distance of the foveal translocation was greater in the 360-degree retinotomy group (3340 microm) than in the partial retinotomy (1060 microm, P <.001) and the limited translocation groups (1120 microm, P <.001). A final visual acuity of 20/200 or better was achieved in two eyes (33%) in the partial retinotomy group, seven eyes (78%) in the limited translocation group, and 23 eyes (64%) in the 360-degree retinotomy group. The final visual acuity improved by 0.2 logarithm of minimal angle of resolution (logMAR) unit or more in one eye (17%), one eye (11%), and seven eyes (19%), respectively. The final visual acuity was maintained within 1 line in zero eyes, five eyes (56%), and 19 eyes (53%), respectively. A retinal detachment developed postoperatively in five eyes (83%), zero eyes (0%), and 15 eyes (42%), respectively.

CONCLUSIONS

A significant number of patients improved or maintained best-corrected visual acuity after translocation with 360-degree retinotomy, and limited translocation, whereas translocation with 360-degree retinotomy is suitable for larger choroidal neovascular membranes because it resulted in the greatest foveal displacement among the three translocation procedures.

Evaluation of the peripheral visual field after foveal translocation

PURPOSE

To evaluate the peripheral visual field after foveal translocation with scleral imbrication or 360-degree retinotomy.

METHODS

Retrospective, single-center, nonrandomized study. We calculated the rate of preservation of the peripheral visual field using Goldmann perimetry by dividing the width of the postoperative V-4 isopter by the preoperative width and expressing the result as a percentage.

RESULTS

In nine eyes that underwent scleral imbrication, the rate of preservation was 100.0% superiorly, 102.6% superotemporally, 99.9% temporally, 97.9% inferotemporally, 96.9% inferiorly, 82.3% inferonasally, 93.7% nasally, and 87.3% superonasally. In 33 eyes that underwent 360-degree retinotomy, it was 89.1%, 87.0%, 81.9%, 78.1%, 86.6%, 90.0%, 89.9%, and 86.8%, respectively.

CONCLUSION

After foveal translocation with scleral imbrication, the peripheral visual field was preserved except for slight narrowing nasally; 360-degree retinotomy resulted in preservation of the visual field, except for slight narrowing in all meridians.

Basic fibroblast growth factor inhibits choriocapillaris atrophy in rabbit

PURPOSE

To examine the effect of basic fibroblast growth factor on induced choriocapillaris atrophy in vivo.

METHODS

Choriocapillaris atrophy was surgically induced in rabbits by a hydraulic retinal detachment followed by debridement of the retinal pigment epithelium under the detached retina. Three concentrations of basic fibroblast growth factor (0.1 microg/0.1 ml, 1 microg/0.1 ml, or 5 microg/0.1 ml) were injected into the subretinal space and into the vitreous cavity 1, 3, and 5 days after the surgery. For control, only Tris buffer was injected in the same manner. The rabbits were euthanized 7 days after the surgery. Choroidal vascular casts were made and examined by scanning electron microscopy. The choriocapillaris atrophy was quantified by computer-assisted image analysis of photographs of the choriocapillaries. The area of the choriocapillaris and number of intercapillary spaces in the choriocapillaris that corresponded to the density of the capillary network were measured.

RESULTS

The average area of the choriocapillaris in the eyes treated with 1 microg/0.1 ml of basic fibroblast growth factor was significantly larger at 75.1 +/- 3.0% than that in the control eyes at 67.2 +/- 5.6% (P =.021). The average area of the choriocapillaris in the 0.1 microg/0.1 ml of basic fibroblast growth factor group was not statistically different from the control. The number of intercapillary spaces of the choriocapillaris was 132 +/- 12 in the 0.1 microg/0.1 ml of basic fibroblast growth factor group, 124 +/- 46 in the 1 microg/0.1 ml of basic fibroblast growth factor group, and 75 +/- 14 in the control group. The higher number of spaces in the treated group was statistically significant (P =.026).

CONCLUSIONS

Basic fibroblast growth factor decreased the atrophy of the choriocapillaris after removal of the retinal pigment epithelium in rabbit eyes. These results suggest that basic fibroblast growth factor may play a role in the survival of the choriocapillaris in vivo.

Effect of a nitric oxide synthase inhibitor on lens-induced myopia

PURPOSE

It has still not been determined whether the retinal mechanism causing form-deprivation myopia (FDM) is different from that causing lens-induced myopia (LIM). We previously reported that FDM was blocked by an intravitreal injection of the nitric oxide (NO) synthase inhibitor, N-nitro-L-arginine methyl ester (L-NAME). In this study, we investigated the effect of L-NAME on LIM in chicks.

METHOD

The left eyes of 6-day-old chicks were injected with 30 microl of nontoxic concentrations of L-NAME (< or = 360 mM) or saline. The right eyes were injected with 30 microl of saline. A -16 dpt lens was placed in front of the left eye for 6 days. Another group of 6 chicks were injected with 180 mM L-NAME (left eye) and with saline (right eye) before placing -16 dpt lenses in front of both eyes. After removing the lens, the refraction and the axial length were measured. The effect of L-NAME (180 mM) on the retina of a separate group of chicks was examined by electroretinography 60 min after an intravitreal injection in non-LIM-treated eyes.

RESULTS

The eyes of chicks that were injected with 180 or 360 mM L-NAME were less myopic and had significantly shorter axial lengths than control eyes. A significant decrease of the On response and an increase of the Off response were observed.

CONCLUSION

The injection of L-NAME into developing chick eyes that were then covered with a -16 dpt lens resulted in a modifications of retinal function and an inhibition of the development of myopia. These results, combined with the earlier findings, suggest that NO modulates a common retinal pathway that leads to both LIM and FDM.

Comparison of visual function after foveal translocation with 360 degrees retinotomy and with scleral shortening in a patient with bilateral myopic neovascular maculopathy

PURPOSE

To compare the visual outcome after foveal translocation by scleral shortening and that after 360 degrees retinotomy with extraocular muscle surgery in a patient with bilateral myopic neovascular maculopathy.

METHODS

Case report.

RESULTS

A 52-year-old woman with bilateral myopic neovascular maculopathy underwent foveal translocation with scleral shortening in the left eye, and visual acuity improved from 20/70 to 20/30. However, choroidal neovascularization recurred, and the final visual acuity was 20/40 after excision of the choroidal neovascularization. Foveal translocation with 360 degrees retinotomy was performed on the right eye, and visual acuity improved from 20/150 to 20/30. The critical print size was better, and the retinal sensitive area was larger in the right eye.

CONCLUSION

The better reading ability shown by foveal translocation by a 360 degrees retinotomy compared with scleral shortening may stem from a larger retinal sensitive area obtained by this method.

Strabismus surgery using the intraoperative adjustable suture method under anesthesia with propofol

PURPOSE

To evaluate the feasibility and efficacy of using the intraoperative adjustable suture method with anesthesia induced by intravenously administered propofol for strabismus surgery.

METHODS

Seven adult patients (mean age, 29.7 +/- 18.5 years) with different types of strabismus were enrolled in this study. All patients underwent full ophthalmological and general medical examinations before surgery. Surgery was performed after induction of anesthesia using intravenously administered propofol that was titrated to control consciousness.

RESULTS

Arousal of consciousness was observed at approximately 2 minutes after discontinuation of the propofol infusion in each case, and the consciousness level was sufficient to allow accurate cover-uncover testing and intraoperative adjustment of sutures. Minor complications of nausea in three patients and vomiting in one patient were noted after surgery.

CONCLUSIONS

Strabismus surgery using the adjustable suture method with propofol intravenous anesthesia appears to be safe and useful for the treatment of adult strabismus.

The effect of nitric oxide on the contractile tone of Müller cells

The effect of nitric oxide (NO) on the contractile tone of Müller cells was investigated. Müller cells, isolated from the retina of chick embryos, were cultured on thin sheets of silicone. S-Nitro-N-acetyl-DL-penicillamine (SNAP), an NO donor, was applied in the presence or the absence of carboxyl phenyltetramethylimidazole oxide (C-PTIO), an NO scavenger. The contractile tone of Müller cells was assessed by the extent of wrinkles created on the silicone sheets. The change of contractile tone was evaluated quantitatively by digitizing the photograph before and after the application of SNAP. Relaxation of wrinkles was induced by SNAP. C-PTIO inhibited the SNAP-induced relaxation of wrinkles. These results suggest that NO affects the contractility of embryonic Müller cells and could thus modulate ocular development.

Foveal translocation: a comparison of two techniques

Subfoveal choroidal neovascular membrane is a leading cause of legal blindness. Photocoagulation has been effective, but photocoagulation of the fovea causes a decrease in vision immediately after treatment. Surgical removal of the choroidal neovascular membrane is effective for choroidal neovascular membrane in some cases, but it restores useful vision for reading (20/40 or better) in a small number of cases of choroidal neovascular membrane not due to presumed ocular histoplasmosis syndrome. A new treatment for subfoveal choroidal neovascular membrane, foveal translocation, is an innovative procedure in which the fovea is translocated onto healthier retinal pigment epithelium. Three techniques have been developed to relocate the retina, 2 of which (retinotomy and scleral shortening) we performed in 5 cases each. Preliminary results in these 10 cases indicate that foveal translocation provides improvement of visual acuity in 40% of eyes and final visual acuities useful for reading (better than 20/40) in 20% of eyes undergoing translocation with either technique. Further study is essential to refine the amount of translocation needed and to decrease complications of the 2 techniques, including retinal detachment, proliferative vitreoretinopathy, macular pucker, corneal astigmatism, and constricted visual field.

Use of dynamic and colored stereogram to measure stereopsis in strabismic patients

The effectiveness of movement or color has not been well studied in assessing stereopsis in patients with strabismus. We developed a new stereotest equipped with both a monochromatic dynamic random dot stereogram (DRDS) and a static-colored stereogram (SCS) and examined the stereopsis of patients with strabismus. Three-dimensional (3D) images were displayed on a liquid crystal display equipped with a parallax barrier system, allowing 3D images to be seen independently by each eye without glasses. A DRDS with maximum disparity of 3200 seconds of arc was displayed having front-rear movement. An SCS displaying cartoon characters with disparities of 400 seconds of arc was also tested and compared with the Titmus stereotest. A total of 52 strabismic patients were tested. The DRDS showed a significantly higher (P = 0.02) detection rate of stereopsis (39/52, 75%) as compared with the Titmus fly test (28/52, 54%). The SCS did not show any difference in the stereopsis detection rate (24/521, 46%) when compared with the Titmus animal test (20/52, 38%). Thus, the DRDS was useful in detecting stereopsis in patients without stereopsis on the conventional Titmus fly test, while the SCS did not show any difference when compared with the Titmus animal test. The DRDS may examine a different aspect of stereopsis from the static stereopsis measured by the Titmus stereotest or SCS.

Value of thyroid stimulating antibody in the diagnosis of thyroid associated ophthalmopathy of euthyroid patients

AIMS/BACKGROUND

Thyroid associated ophthalmopathy (TAO) of euthyroid patients is difficult to diagnose because clinical findings overlap with other conditions, and no confirmatory diagnostic tests are available. Recently, it was reported that TSH binding inhibitor immunoglobulin (TBII) and thyroid stimulating antibody (TSAb) are sensitive markers of TAO. The sensitivity of these antibodies in the detection of TAO were therefore studied to determine if they could be a useful criterion in the diagnosis of TAO of euthyroid patients.

METHODS

Serum values of TBII and TSAb of 35 patients with euthyroid TAO (group A) were compared with those of 27 patients with Graves' disease and TAO (group B). The relation between the serum value of TSAb and the eye symptoms of patients with euthyroid TAO were also examined by multiple linear regression analysis.

RESULTS

In group A, TBII was positive in 10 cases (28.6%) and TSAb was positive in 29 cases (82.9%). In group B, both TBII and TSAb were positive in all cases (100%). The titre of serum TBII in group A (15.6% (SD 18.0%)) was significantly lower (p < 0.0001) than in group B (57.9% (21.5%)). The titre of serum TSAb in group A (1400.9% (2163.9%)) was significantly lower (p = 0.0026) than in group B (2243.9% (1472.8%)). Among the eye findings of patients with euthyroid TAO, keratopathy was significantly (p = 0.034) related to the value of TSAb.

CONCLUSION

These results suggest that the activity of TSAb is a more sensitive marker of euthyroid TAO than is TBII, and could be a useful criterion in the diagnosis of TAO of euthyroid patients.

Human hepatocyte growth factor (HGF) in the aqueous humor

Using an enzyme-linked immunosorbent assay, we measured the concentration of hepatocyte growth factor (HGF) in human aqueous humor and serum from 36 eyes of 33 patients and analyzed the relationship between HGF and several parameters of corneal endothelial cells. Aqueous HGF concentrations ranged from 0.020-0.194 ng/mL (average: 0.101 +/- 0.044 ng/mL) and was correlated positively with corneal endothelial cell density (r = 0.343, P = 0.04). The aqueous HGF level did not correlate with other corneal endothelial cell parameters or the serum HGF level. The HGF receptor, c-Met, was found in the corneal endothelial cell membranes. This study suggests that the aqueous humor HGF is a factor which maintains an integrity of corneal endothelial cells.

A clinical evaluation of stereopsis required to see 3-D images

Some children with esotropia who have been diagnosed as 'stereoblind' on the basis of conventional stereotests (which principally use static images with small disparity) may nevertheless enjoy stereopsis for three-dimensional (3-D) animations that use dynamic images with large disparity. The purpose of this study was to develop a new stereotest equipped with dynamic random-dot stereogram (DRDS) which has larger disparity with movement and use it with esotropic children to see if they can attain stereopsis for such images. Subjects were 17 esotropic children between 5 and 10 years old (mean age 6.8 years) who had failed to demonstrate stereopsis with the Titmus fly test. Seven children had infantile esotropia and 10 had partially accommodative esotropia. The test images were DRDS that were presented on a fluorescent screen (12 x 9 cm) viewed through a lenticular lens. The dots were displayed in circle and triangle patterns that have counterphase front-rear movement with maximum disparity of 800 s. Patients were placed with eyes at a distance of 60 cm from the screen and were instructed to point out the pattern (circle or triangle) that was produced. The average angle of strabismus was 7.7 delta by alternating prism cover test (5 m). Seven patients passed and 10 failed the DRDS test. There was no significant difference in the mean angle of strabismus or the age of examination between the two groups; however, the age at onset of strabismus was significantly higher in those who passed the DRDS test. These results suggest that the DRDS test is useful in evaluating the potential stereopsis in children with esotropia who do not pass conventional stereotests.

ERG of form deprivation myopia and drug induced ametropia in chicks

Chick eyes occluded for various periods or treated with various concentrations of kainic acid (KA) or 2-amino-4-phosphonobutylate (APB) during development showed characteristic changes of electroretinography and of refraction. In occluded eyes, oscillatory potential amplitudes (OP-A) were reduced, even with high-intensity stimulation, in proportion to duration of occlusion, but b wave amplitude was unchanged, implying functional changes in inner layers of the deprived retina. OP-A reduction after only 1 week of occlusion and reversibility of this change might reflect retinal changes preceding axial elongation. KA was confirmed to induce myopia with axial elongation and APB to induce hyperopia with axial shortening. KA and APB both suppressed OP-A. KA reduced ON and OFF responses, but low-dose APB suppressed only ON responses. Study results suggest that myopia could be induced by changes of inner retina mediating OP attenuation and degradation of ON and OFF responses. This manuscript reports unpublished work that is not currently under consideration for publication elsewhere.