[Laser-scanning-tomography in clinical routine]. / Die Laser-Scanning-Tomographie in der Glaukomsprechstunde.

Scanning laser tomography using the Heidelberg Retina Tomograph (HRT) aims at a three-dimensional reconstruction of optic disk topography based on two-dimensional optical section images. Topometric parameters describe the optic disk configuration, algorithms calculate the likelihood of already existing glaucomatous tissue alterations. In the follow-up of chronic glaucoma, this imaging technique has become the gold standard for quantitative optic nerve head evaluation.

Interobserver variability of optic disk variables measured by confocal scanning laser tomography.

PURPOSE: To assess the interobserver variation of confocal laser scanning tomographic measurements of the optic nerve head and to address the question of whether the addition of clinical optic disk photographs is helpful in outlining the optic disk margin and in reducing the observer-related variation of the measurements. PATIENTS AND METHODS: Optic disk variables for 16 eyes of 16 patients with glaucoma, generated by confocal laser scanning laser tomography (Heidelberg Retina Tomograph), were independently evaluated by four experienced glaucoma specialists, and the interobserver variability was calculated. A second separate review by the same observers included the use of clinical stereoscopic color optic nerve head photographs to aid definition of the optic disk margin. RESULTS: Optic disk parameters with the smallest interobserver variation were cup shape measure, maximum cup depth, height variation contour, and mean height contour. The intraobserver variation of these parameters did not increase when clinical optic disk slides were additionally available. Parameters with the highest interobserver variation were volume below surface, volume below reference, volume above surface, and volume above reference. The observer variation of these optic disk parameters increased significantly for two of the four examiners when clinical optic disk slides were additionally available for outlining the optic disk margin. CONCLUSION: Confocal laser scanning tomography of the optic nerve head can be improved significantly if clinical optic disk photographs are additionally available to help in outlining the optic disk margin. Because interobserver variation in the tomographic optic disk measurements can be significant, even if experienced observer are involved, tomographic optic disk measurements may be centralized in reading centers in the case of multicenter studies.

Clinical detection of optic nerve damage: measuring changes in cup steepness with use of a new image alignment algorithm.

The purpose of this study was to study the effect of a subpixel image alignment algorithm on the standard deviation (SD) of mean topography images obtained by laser scanning tomography and to evaluate changes of the cup shape measure parameter (CSM) over time based upon the individual parameter variability using the new algorithm. Triple measurements from optic nerve heads of 132 eyes of 132 subjects were obtained using the Heidelberg Retina Tomograph HRT. To calculate a mean topography image from three single topography images, alignment of the raw optical section image data was performed with the standard software and again with a new subpixel-based image alignment algorithm. The effect on the averaged (SD) of the mean topography images was evaluated. CSM was evaluated in 15 eyes of 15 normal subjects (N) and 28 eyes of 14 glaucoma patients (G) over a period of 28.6 +/- 4.6 months (N) and 28.56 +/- 5.2 months (G) respectively. A change in the CSM value over time was considered significant if CSM measurements exceeded two standard deviations of this variable determined for the individual eye. Mean-topography image SD was 22.86 +/- 8.2 microns (min. 9.5 microm; max. 47.8 microm) with the standard alignment procedure and 15.46 +/- 6.8 microm (min. 6.8 microm; max. 42.8 microm) with the new algorithm. The average SD improvement was 7.46 +/- 3.9 microns (min. -8.1 microm; max. 28.7 microm). The coefficient of correlation of both methods was R(2) = 0.77 (p < 0.0001). No control group eye demonstrated significant changes of CSM in the follow-up period. The CSM indicated an increase in cup steepness in 4 eyes of 4 glaucoma patients. In one of these four eyes, a deterioration of the visual field was identified by white on white perimetry. The new image alignment algorithm significantly reduces the SD of mean topography images calculated from identical raw data. If topometric variables are evaluated over time, the individual variability of data should be taken into account.

Clinical results of phacoemulsification with the use of Healon5 or Viscoat.

PURPOSE: To compare the ophthalmic viscosurgical devices Healon5 (viscoadaptive) and Viscoat (dispersive) regarding their overall clinical performance during phacoemulsification and posterior chamber intraocular lens (IOL) implantation as well as their influence on intraocular pressure (IOP). SETTING: Department of Ophthalmology, Ruprecht-Karls-University Heidelberg, Heidelberg, Germany. METHODS: In this prospective randomized patient- and observer-masked clinical study, the performance of Healon5 (sodium hyaluronate 2.3%) and Viscoat (sodium hyaluronate 3.0%-chondroitin sulfate 4.0%) was assessed by 3 surgeons during cataract surgery in 90 patients. Surgeons used a 5-point scale for the subjective assessment of the ease of injection, maintenance capacity during continuous curvilinear capsulorhexis, remaining capacity during phacoemulsification, facilitation of IOL implantation, removal from the eye, transparency, and overall performance throughout surgery. Intraocular pressure was measured preoperatively and 24 hours and 7 days postoperatively. Best corrected visual acuity was assessed preoperatively and 7 days postoperatively. RESULTS: Overall intraoperative product performance was assessed as good or very good in 34 of 44 patients (77%) in the Healon5 group and in 16 of 46 patients (35%) in the Viscoat group (P <.001). Retention in the anterior chamber was graded good or very good in 36 patients (82%) in the Healon5 group and in 23 (50%) in the Viscoat group (P =.001). There were no statistically significant between-group differences in mean IOP preoperatively and 24 hours postoperatively. CONCLUSIONS: Surgeons graded Healon5 better than Viscoat in overall surgical performance and retention in the anterior chamber during phacoemulsification. These data support that Healon5 adapts to each step during surgery.

Search for an optimal combination of structural and functional parameters for the diagnosis of glaucoma. Multivariate analysis of confocal scanning laser tomograph, blue-on-yellow visual field and retinal nerve fiber layer data.

BACKGROUND: The purpose of this study was to evaluate which of the structural and functional parameters--the Heidelberg Retina Tomograph (HRT), white-on-white (W/W) and blue-on-yellow (B/Y) visual fields and semiquantitative retinal nerve fiber layer (RNFL) scoring parameters--can give the best separation between non-glaucomatous and glaucomatous eyes. METHODS: Fifty-five subjects were included in this study: 32 nonglaucomatous subjects with mean age of 54 years, and 23 patients with ocular hypertension or glaucoma and mean age of 59 years. The HRT with software 1.11, the Humphrey 30-2 W/W and lens coloration-corrected B/Y visual fields, and semiquantitative RNFL scores were utilized. Stepwise logistic regression analysis was used in finding, from a given set of parameters, a best discriminating parsimonious subset to a logistic model, the discriminatory performance of which was evaluated by the area under the ROC curve. RESULTS: When all the structural and functional variables were considered, the RNFL total overall score gave the best separation between glaucomatous and non-glaucomatous eyes (ROC area 0.98). Without the RNFL scores and optic disc size-dependent HRT parameters in the model, the cup shape measure was selected first (ROC area 0.88). In the second step the RNFL thickness was selected (ROC area 0.91), and in the third step the corrected B/Y mean deviation (MD) was selected (ROC area 0.91). With only the HRT parameters in the model, the cup/disc ratio was selected first (ROC area 0.88). However, when the groups were matched for optic disc size, all disc size-dependent HRT variables lost their discriminant power. CONCLUSION: Cup shape measure and RNFL thickness, together with age- and lens coloration-corrected MD of the B/Y perimetry provided good discrimination between healthy individuals and patients with glaucoma.

Development of the standard reference plane for the Heidelberg retina tomograph.

BACKGROUND: Topometry of the optic disc is the quantitative assessment of the structure of the optic nerve head by means of three-dimensional parameters. The parameter values depend on definitions of intraocular reference planes. PURPOSE: To describe the development of intraocular reference planes in laser scanning tomography for the Heidelberg Retina Tomograph (HRT) using image intrinsic data with a fixed offset reference plane (320 microm) and to present a contour-line-based "flexible" standard reference plane ("SRP") for calculation of intrapapillary stereometric parameters taking the interindividual variability of optic disc topography into account. METHODS: Ten-degree triple images were obtained by laser scanning tomography from 99 glaucoma eyes and 180 normal eyes. The images were evaluated to assess the variability of height measurements of an optic disc border contour-line segment (6 degrees width) corresponding to the site of the papillo-macular bundle as indicated by the average optic disc surface inclination angle. RESULTS: The average optic disc surface inclination angle was -7 degrees +/- 3 degrees below the horizontal meridian (0 degrees). The 6 degrees wide contour-line segment for the SRP was chosen according to the average surface inclination angle (-10 degrees to -4 degrees). The reproducibility of the SRP-segment height measurements was 16.0+/-10.8 microm for normal eyes and 23.4+/-18.0 microm for glaucoma eyes. To ensure that the automatic reference level determination for intrapapillary parameters remained below the disc border height, we defined the SRP level at a 50 microm offset (>2 SD of average segment height reproducibility in glaucoma) added to the individual height position of the 6 degrees contour line segment. CONCLUSION: The flexible standard reference plane allows for automatic determination of intrapapillary variables once a disc border contour line is interactively defined. In contrast to a fixed offset reference plane (e.g. 320 microm below the mean retina height), the interindividual variability of optic disc topography (oblique insertion, glaucomatous surface flattening) is respected at the cost of the need for an accurate optic disc border outline.

Corneoscleroplasty with maintenance of the angle in two cases of extensive corneoscleral disease.

PURPOSE: We report a 2 year follow-up in two patients after corneoscleroplasty. METHOD: Using lamellar corneoscleral dissection to maintain the drainage angle and its function, we performed a 14 mm allograft corneoscleroplasty in 2 eyes. For surgical treatment in both cases a 9.5 mm corneal button was excised from the recipient after peritomy and scleral lamellar preparation up to 14 mm. A 14 mm donor button was inserted and held in place with multiple Prolene sutures. One eye presented with a large perforating corneal ulcer after herpetic keratitis in a patient with recurrent rheumatoid uveitis associated with rubeosis iridis. The second eye had had a penetrating keratoplasty for keratoconus 30 years previously and presented with decompensating keratoglobus. Immune suppression was performed with systemic cyclosporin A and additional steroids when required. RESULTS: Both patients had a clear graft at the last follow-up visit and visual acuity was improved to a best corrected visual acuity of 0.6. Intraocular pressure in the keratoglobus eye was maintained at 6 mmHg without treatment, whereas the second case required continuing treatment with systemic acetazolamide because of neovascular glaucoma. The anterior chamber angles remained open in both patients. Contact lenses were helpful in the prevention of epithelial irregularities and defects. Both patients had an episode of immunological graft reaction which was reversed by immunosuppressive treatment. Phacoemulsification with intraocular lens implantation, which was performed 2 years after transplantation in the keratoglobus eye, did not affect the graft clarity or cause rejection episodes. CONCLUSION: Our results using corneoscleroplasty have been encouraging in severe destructive corneal disease.

[Blindness caused by an airbag in a minor accident]. / Erblindung durch Airbag bei Bagatellunfall.

PURPOSE: Installation of airbags has reduced the rate of fatal injuries in severe automobile accidents. We report, however, severe ocular injuries in a minor accident as the result of an airbag. CASE REPORT: A front passenger suffered a blunt ocular trauma of her right eye during a collision. The approaching speed was about 31 km/h. The maximum change of velocity in direction of the impact was 19 km/h. Color traces were found on the upper rim of the airbag, apparently from the patient's eye shadow. RESULTS: In the emergency room, visual acuity was reduced to light perception. There was endothelial contusion, traumatic mydriasis, and lens subluxation. A sclopetarian retinopathy developed with a chorioretinal scar. Eight months after the accident visual acuity remained at light projection only. CONCLUSIONS: The eye injuries had very probably been caused by the deploying airbag. Improvements are a better geometry of deployment (e.g., tethered airbags), release at higher impacts only, and "intelligent systems" with additional sensors to avoid potentially hazardous airbag inflation in minor accidents.

Magnification characteristics of fundus imaging systems.

OBJECTIVE: To compare the magnification properties of 11 different fundus cameras (including 1 stereo fundus camera), a Rodenstock (infrared) scanning laser ophthalmoscope (SLO), the Heidelberg Laser Tomographic Scanner (LTS), and the Heidelberg Retina Tomograph (HRT). DESIGN: A cross-sectional study of the relationship between the true size of a fundus feature and its photographic-computer image in 14 different fundus imaging devices. This relationship was evaluated for each instrument using a model eye adjusted for axial ametropia between +11 diopter (D) and -14 D. To simulate refractive ametropia, the "crystalline lens" was removed to render the model eye aphakic, and the axial length was adjusted to give aphakic ametropia from emmetropia to +20 D. MAIN OUTCOME MEASURES: A correction factor (p) was calculated for each instrument, which can be used in calculations for determining true retinal size. RESULTS: The following were found to be of telecentric construction, Zeiss Oberkochen (WS240 Heidelberg), Zeiss Oberkochen (UK), Zeiss Oberkochen (Cologne), Nikon NF505, Kowa RCXV, SLO prototype (UK), LTS, and the HRT, and each exhibited a constant relationship between p and degree of ametropia of the model eye. The Canon CF6OU, Canon CF6OS, Canon CR4-45NM, Nidek 3-DX, Olympus GRCW, and Carl Zeiss Jena Retinophot were found not to be telecentric and exhibited a linear relationship between p and degree of ametropia of the model eye. For all instruments, p remained unchanged for axial and refractive ametropias of the same degree. CONCLUSIONS: The study has shown that not all fundus imaging systems are telecentric, so the use of a single magnification correction value may not be appropriate. These findings have important implications for the way in which true retinal size calculations are performed. Examples are given to show how the tabulated values of correction factors can be used for both telecentric and nontelecentric cameras in image size calculations.

Simultaneous confocal scanning laser fluorescein and indocyanine green angiography.

PURPOSE: To evaluate clinically a recently developed confocal scanning laser ophthalmoscope for simultaneous fluorescein and indocyanine green angiography. METHODS: After comprehensive ophthalmic examination, including stereoscopic biomicroscopy, and after color fundus photographs, simultaneous confocal scanning laser fluorescein and indocyanine green angiography was performed after injection of 500 mg of fluorescein and 25 mg of indocyanine green mixed in one syringe using the Heidelberg Retina Angiograph. An argon laser beam (488 nm) and a diode laser beam (795 nm) from an external source were delivered by single-mode fibers. Emission was recorded between 500 and 700 nm and above 810 nm, respectively. Digital images were displayed simultaneously on a monitor during angiography. RESULTS: Two hundred twenty simultaneous fluorescein and indocyanine green angiograms were obtained in 193 consecutive patients with various diagnoses, including exudative age-related macular degeneration with occult and classic choroidal neovascularization. Simultaneous angiography with both dyes gave high-contrast images during all phases of the angiography, which allowed for accurate correlation of fluorescein and indocyanine green angiographic findings and correct comparison of the transit of both dyes through the retinal and choroidal circulation. Corresponding display of quasisimultaneous frames facilitated interpretation of the angiograms. CONCLUSIONS: Confocal laser scanning angiography allows for quasisimultaneous fluorescein and indocyanine green angiography. The investigation is possible at low retinal irradiance and offers high-contrast digital images. Compared with consecutive angiographic investigations using both dyes, simultaneous angiography is less time consuming, requires only one injection, and, because quasisimultaneous frames are obtained, facilitates interpretation of the angiograms.

Laser scanning tomography of localised nerve fibre layer defects.

AIMS: Retinal nerve fibre layer photography is a well established method to qualitatively document early structural changes which might be induced by primary open angle glaucoma. The aim was to analyse localised retinal nerve fibre layer (RNFL) defects in a new quantitative way with respect to surface topography, defect width, and surface reflectivity by means of the technique of confocal scanning laser tomography. METHODS: 12 eyes of 12 patients with a localised RNFL defect documented in RNFL photographs and a normal appearance of the optic disc were enrolled in the study. Using confocal laser scanning tomography (Heidelberg retina tomograph, HRT) a series of 32 optical section images from different focal planes of the retina at the site of the RNFL defects were obtained. The optical section images, the reflectivity images, and the topographic images were analysed regarding the visibility of the RNFL defects. The mean surface height and the reflectance at the sites of the RNFL damage were measured and compared with the adjacent apparently normal retina. The width of the RNFL defect at 1 mm distance from the disc border was evaluated. RESULTS: RNFL defects could be detected in nine of 12 reflectivity images (75%). Single optical section images displayed the RNFL defects in 12 of 12 eyes. The defect width ranged from 0.11 to 1.0 mm. In six of 12 eyes a surface depression (34 (SD 5) microns; range 21-47 microns) was present. The reflectance ratio ranged from 0.68 to 0.94 at the site of the RNFL defect. In eyes with a glaucomatous scotoma in a 6 degrees grid visual field (VF), the defect width was at least 0.25 mm. Surface depression and low reflectance ratio were found irrespective of the presence of a scotoma in the 6 degrees grid VF. CONCLUSION: The majority of localised RNFL defects can be detected in reflectivity images from laser scanning tomograms. Localised RNFL defects may be differentiated according to surface topography into those with and those without a measurable surface depression. A small but deep RNFL defect is not necessarily associated with a scotoma in routine 6 degrees grid VF static perimetry.

[Simultaneous fluorescein and indocyanine green angiography with a confocal laser ophthalmoscope]. / Simultane Fluorescein- und Indozyaningrünangiographie mit einem konfokalen Scanning-Laser-Ophthalmoskop.

BACKGROUND: We report on our clinical experience with a recently developed confocal scanning laser ophthalmoscope for simultaneous fluorescein and indocyanine-green (ICG) angiography. MATERIALS AND METHODS: Following injection of fluorescein and ICG mixed in one syringe simultaneous confocal scanning laser fluorescein and ICG angiography were carried out using the Heidelberg Retina Angiograph (HRA). An argon laser (488 nm) and a diode laser beam (795 nm) from an external source were delivered via single-mode fibers. Emission was recorded between 500 and 650 nm and above 810 nm, respectively. Digital images were displayed simultaneously on a monitor during angiography. RESULTS: A total of 295 simultaneous angiograms in 268 patients with various retinal and choroidal diseases, including exudative age-related macular degeneration with occult and classic choroidal neovascularization, were obtained. High-contrast images during all phases of the angiography were obtained. Besides mild side effects in similar frequency known from individual injections, no additional toxic or allergic reactions from simultaneous injections of the two dyes were observed. CONCLUSIONS: Confocal laser scanning angiography allows for simultaneous fluorescein and ICG angiography. Compared with consecutive investigations using both dyes, simultaneous angiography requires only one injection, and offers identical digital frames. Simultaneous injection is not associated with additional side effects.

Comparison of optic disc measurements by Heidelberg Retina Tomograph and manual planimetric techniques.

The inner edge of the scleral ring is used as a reference plane for manual, computer assisted optic disc measurements. As it is possible to identify this level with the Heidelberg Retina Tomograph, our aim was to compare manual measurements to those taken with the Heidelberg Retina Tomograph. The material of this pilot study consisted of 12 eyes of 12 patients with early glaucomatous optic disc, retinal nerve fiber layer and/or visual field abnormalities. Measurements of the optic disc and neuroretinal rim area were obtained using our manual planimetric techniques, and the Heidelberg Retina Tomograph. The mean optic disc areas measured smaller with the Heidelberg Retina Tomograph than with the manual techniques (average difference 0.13 mm2; p < 0.05). The neuroretinal rim area measurements and cup-to-disc area ratio using manual and Heidelberg Retina Tomograph techniques did not differ statistically significantly from each other. With the scleral ring as a reference plane, comparable optic disc measurements can be obtained with manual and laser techniques.

Current imaging of the optic disk and retinal nerve fiber layer.

The optic nerve head and the retinal nerve fiber layer (RNFL) are the sites of clinically detectable glaucomatous tissue damage. Photographic techniques are used to document the optic disk and the RNFL to monitor patients with suspected primary open-angle glaucoma or to follow-up patients already suffering from this disease. New techniques such as laser scanning tomography (LST), scanning laser polarimetry, and optical coherence tomography have been introduced to quantify structural alterations with the aim of early detection of optic nerve or RNFL damage prior to functional loss. These novel, additional diagnostic tools are currently being evaluated in clinical practice. While scanning laser polarimetry and optical coherence tomography are discussed elsewhere in this volume, articles on LST and conventional techniques are considered here. Imaging and computed data processing allow for three-dimensional in vivo measurements in the range of micrometers. With regard to the structure of the optic nerve head, this aspect in the evaluation of the optic disk can be based on quantitative topographic data. We expect "topometry" to become an important additional tool in the early diagnosis and follow-up of patients with glaucoma. However, computed parameter readings should always be evaluated in a clinical context. The goal is to improve, combine, and integrate all the different diagnostic approaches to improve patient care for the benefit of those suffering from glaucoma.

[Comparison between local and systemic administration of cyclosporin A on the effective level in conjunctiva, aqueous humor and serum]. / Vergleich zwischen lokaler und systemischer Applikation von Cyclosporin A auf den Wirkspiegel in Bindehaut, Kammerwasser und Serum.

Cyclosporine is an important tool for the therapy of immunological diseases of the cornea and conjunctiva, as well as the treatment of patients with high-risk corneal grafts. However, potentially severe systemic side effects are disadvantageous. The purpose of our study was to determine if topical ocular application leads to about the same concentrations in ocular tissues as systemic application. Therefore, the concentration of cyclosporine in conjunctiva, aqueous humor and blood was measured by radioimmunoassay in six patients with systemic administration of cyclosporine and ten patients who received one drop of topical cyclosporine 2% four times prior to cataract surgery. All patients with systemic application showed measurable concentrations of cyclosporine in blood, as did four patients in the group receiving topical cyclosporine. There was no significant difference between both groups concerning cyclosporine concentration in aqueous humor. The level of cyclosporine in the conjunctiva was significantly higher after topical application (P < 0.02). In conclusion, therapy with cyclosporine eye drops results in levels in the conjunctiva and aqueous humor that are comparable to or even higher than those after systemic application if the last application was no more than 18h prior to the measurement. Therefore, topical ocular application of cyclosporine, which reduces or eliminates the drug's systemic side effects, can be used to induce local immunosuppressive activity, particularly in the treatment of superficial immunological diseases and after limbal allograft transplantation.

[Possibilities for imaging the retinal nerve fiber layer with the scanning laser ophthalmoscope]. / Darstellungsmöglichkeiten der retinalen Nervenfaserschicht mit dem Scanning-Laser-Ophthalmoskop.

BACKGROUND: Documentation of the retinal nerve fiber layer using red free light is not established as a routine method. The reasons for this are the difficulties involved in taking the pictures and developing them, especially in glaucoma patients, and the need for maximum pupil dilation. The scanning laser ophthalmoscope (SLO) allows fast and easy documentation of the fundus with the possibility of simultaneous image control during the examination. PATIENTS AND METHODS: Nerve fiber layer images of 48 eyes of 25 patients taken with the argon blue light of the SLO were compared to conventional photographs of the nerve fiber layer with red-free light. In addition, we compared documentation of the nerve fiber layer using argon-blue or argon-green light in the SLO. RESULTS: The nerve fiber layer images obtained with the SLO were of good quality for all 48 eyes included in the study, whereas with conventional photography we could not obtain images in 9 eyes. There was a high correlation between the two methods in the detection of localized damage or zones with diffuse nerve fiber atrophy for the 39 eyes documented with both methods, and there was better image quality in some using the SLO. The use of blue light permits the nerve fiber layer to be seen more easily than with green light. CONCLUSIONS: The SLO allows nerve fiber bundle defects or diffuse atrophy to be detected similar to conventional fundus photographs using red free light sources. There is no further need to dilate the pupil maximally due to the confocal principle and the scanning technique. The smaller angle of view of the SLO requires fixation movements of the patient being examined for the detection of beginning peripheral nerve fiber bundle defects.

[Confocal scanning laser indocyanine green angiography with the Heidelberg retinal angiograph]. / Konfokale Scanning-Laser-Indocyaningrün-Angiographie mit dem Heidelberg Retina Angiograph.

PURPOSE: Indocyanine-green angiography (ICG) has been shown to be a valuable adjunctive technique to fluorescein angiography including further delineation of choroidal neovascularization in age-related macular degeneration. We report on initial clinical experiences with a newly developed infrared confocal scanning laser ophthalmoscope. MATERIALS AND METHODS: Fundus and fluorescein angiography photographs were obtained in 20 patients with various fundus changes. Confocal laser scanning ICG-angiography using the Heidelberg Retina Angiograph (Heidelberg Engineering GmbH, Germany) was performed after injection of 25 mg ICG. The confocal principle ensures that only light reflected from a defined focal plane is detected by the integrated photomultiplier. Excitation wave-length was 795 nm, and emission was recorded above 810 nm. About 60% of the emission is detected. An additional built-in diode laser (830 nm) allowed fundus visualization prior to dye injection. RESULTS: ICG angiography using the scanning laser angiograph showed typical findings as previously reported with other systems. The images were characterized by high contrast. In addition, the retinal vessels were readily visualized in the late phase. By means of the confocal mode different layers of the circulation could be visualized. CONCLUSIONS: The findings indicate that the confocal scanning angiograph is a useful alternative tool for ICG angiography and that it offers similar information obtained by other imaging systems. Advantages compared with previous techniques may include high image contrast, visualization of retinal vessels in the late phase, lower amount of light exposure, direct digital image acquisition and easy practical operation.

[Follow-up examinations of papillary morphology with laser scanning tomography]. / Verlaufsuntersuchungen der Papillenmorphologie mittels Laser-Scanning-Tomographie.

UNLABELLED: The object of this study was to investigate the perceptibility of changes in the topography of the optic nerve head during follow up with laser scanning tomography (LST), with a minimum observation period of 24 months. METHODS: We evaluated the changes in cup and rim area, cup volume, and mean and maximum cup depth in 50 eyes (8 control eyes, 21 glaucomatous eyes, 21 eyes in which glaucoma was suspected by LST over a mean follow-up time of 36 +/- 10 (range 24-49) months and compared them with the results of computerized static perimetry (Octopus). Changes were considered to be significant if they were larger than three times the maximum deviation measured in one parameter and larger than the maximum deviation in one other parameter [27]. RESULTS: Among 10 eyes that showed increasing cup values, 5 initially presented with striking disc cups, and no pathologic function tests; in none of these eyes was functional loss revealed by perimetry during the follow-up period. Of the 5 glaucomatous eyes in which progression was found on optic disc morphometry, 4 had increasing defects revealed by computerized static perimetry (Octopus 500). CONCLUSION: The results confirm the value of LST. In 6 eyes in which LST revealed a significant increase in the optic cup values, perimetry did not demonstrate progression of the functional loss. Therefore, LST should be used in the follow up of all patients with glaucoma or suspected glaucoma, in addition to conventional computerized perimetry.