[Specifity of optic disc evaluation in healthy subjects with large optic discs and physiologic cupping using confocal scanning laser ophthalmoscopy]. / Spezifität der konfokalen Scanning Laser Ophthalmoskopie bei großen Sehnerven mit physiologischer Exkavation.

PURPOSE: Imaging methods of the optic nerve head appear to have an increasing impact in glaucoma diagnosis. The aim of this study is to evaluate the specifity of the Heidelberg Retina Tomograph (software version 1.7 and 3.0) in subjects with physiological cupping and large optic discs. PATIENTS AND METHODS: 27 eyes of 27 subjects (mean age 41.3 ± 15.8 years) with bilateral physiological cupping and large optic discs (vertical cup-to-disc-ratio > 0.3, optic disc area 2.48 ± 0.45 mm2, max. 3.54 mm2) were included in a clinical study. All subjects had an intraocular pressure < 22 mmHg, physiological cupping by funduscopy and no nerve fibre layer defects (Scanning Laser Ophthalmoscope, Rodenstock, Germany). Standard achromatic perimetry (Humphrey Field Analyzer, Humphrey-Zeiss, 24/2 SITA or full threshold), short-wavelength automated perimetry (Humphrey Field Analyzer, Humphrey-Zeiss), and frequency doubling technology (FDT, Humphrey-Zeiss) revealed no visual field defects. Optic disc imaging was performed in all subjects using the Heidelberg Retina Tomograph II (HRT). Optic disc images were transferred to the software-update of the HRT 3 (Version 3.0, Heidelberg Engineering). Specifity was calculated using the Moorfields regression analysis (MRA, software version 1.7 and 3.0) and the glaucoma probability score (GPS analysis) using all disc sectors and omitting the nasal and 3 nasal sectors. RESULTS: Specifity of the MRA (software version 1.7) was 66.6 % (most specific criteria), and 22.2 % (least specific criteria). Specifity of the MRA (software version 3.0) was 33.3 % (most specific criteria), and 14.8 % (least specific criteria), whereas specifity of the GPS analysis was 37.0 % (most specific criteria), and 11.1 % (least specific criteria). When the nasal sectors were omitted for analysis, specifity increased for the MRA analysis, but not for the GPS analysis. CONCLUSIONS: Specifity of the MRA was unsatisfactory using the software version 1.7 and 3.0 in subjects with large optic discs and physiological cupping when the nasal sectors were included in the analysis. The observer-independent GPS analysis did not improve the results in these subjects.

[Long-term results after trabeculectomy with 5-fluorouracil]. / Langzeitergebnisse nach Trabekulektomie mit 5-Fluorouracil.

PURPOSE: Trabeculectomy is among the first choice surgical treatments for glaucoma. Antimetabolites, especially mitomycin C, have improved the success rate. The aim of this study is to present the results of trabeculectomy with 5-fluorouracil (5-FU). METHODS: A total of 71 consecutive trabeculectomies with 5-FU for decompensated glaucoma with at least 1 year follow-up data were retrospectively evaluated. The absolute (without therapy) and relative (with therapy) success rates for glaucoma medication were determined for intraocular pressure (IOP) levels of ≤ 21 mmHg, ≤ 18 mmHg, ≤ 15 mmHg and ≤ 12 mmHg respectively. Postoperative 5-FU administration rates, needling procedures and complications were recorded. RESULTS: Sufficient follow-up data were available for a total of 55 patients. The average IOP was preoperatively 29.6 ± 7.3 mmHg (3 ± 1.4 active ingredients, partly acetazolamide), after 6 months 13.2 ± 4.1 mmHg and after 1 year 13.7 ± 4.3 mmHg. Complete success at 6 months postoperatively for the given pressure levels: were 92 %, 87 %, 79 % and 52% and at 1 year 87 %, 84 %, 51 % and 56%, respectively. Postoperative relative success for these pressure levels at 6 months were 96 %, 90 %, 81 % and 54% and at 1 year 96 %, 93 %, 58 % and 58%, respectively. Administrations of 5-FU postoperatively were no intervention (n=30 patients), subconjunctival 5-FU administration (n=25) and needling procedures (n=6). A temporary hypotension with a shallow anterior chamber was seen in 6 patients, cataract development in 5 patients and 1 patient developed corneal decompensation (multiple previous operations before trabeculectomy). CONCLUSION: Trabeculectomy with intraoperative 5-FU administration showed very high success rates after 1 year. Serious complications were rarely seen. Intraoperative 5-FU administration can be considered as an alternative treatment to trabeculectomy with intraoperative use of mitomycin C.

[Color Doppler sonography of retrobulbar vessels and hypercapnia in normal tension glaucoma]. / Farbduplexsonographie der retrobulbären Gefäße und Hyperkapnie bei Normaldruckglaukom.

PURPOSE: The aim of the study was to investigate retrobulbar flow velocities during hypercapnia in patients with normal tension glaucoma (NTG) without systemic vasospasm and jn controls. METHODS: A total of 16 NTG patients (mean age 58 ± 14 years) and 16 control subjects (mean age 50 ± 13 years, p = 0.10) were enrolled in this study. Flow velocities, peak systolic velocity (PSV), end-diastolic velocity (EDV) and resistive indices (RI) of the ophthalmic (OA) and central retinal arteries (CRA) were assessed using color Doppler imaging. Blood flow velocities were measured under normocapnic and hypercapnic conditions (increasing the end-tidal pCO(2) by 15%). Blood pressure, ventilation rate and oxygen saturation were monitored simultaneously. RESULTS: During hypercapnia, velocity responses of the PSV (p = 0.044) and EDV (p = 0.037) of the CRA were significantly different in NTG patients and healthy controls, showing a greater increase of flow velocities in control subjects. Flow velocities of the OA increased significantly in both groups (PSV p = 0.039, EDV p = 0.003) during hypercapnia. Blood pressure, oxygen saturation and intraocular pressure changed similarly in both study groups with carbon dioxide provocation. CONCLUSIONS: Velocity response to hypercapnia was reduced in the CRA of NTG patients compared to controls. This may indicate a faulty vasodilatory response in NTG patients without vasospastic disease.

[Quantification of fluorescein angiography in patients with non-arteritic anterior ischemic optic neuropathy]. / Quantifizierung von Fluoreszenzangiographien bei Patienten mit nichtarteriitischer anteriorer ischämischer Optikusneuropathie.

PURPOSE: The aim of this study was to evaluate the retinal hemodynamics and optic disc leakage by fluorescein angiography in patients with non-arteritic anterior ischemic optic neuropathy (NAION) and to correlate fluorescein angiography findings with the extent and topography of visual field loss. METHODS: A total of 26 patients with acute NAION were included in the study. Fluorescein angiograms were performed by means of a scanning laser ophthalmoscope. The extent of early-phase optic disc leakage was assessed using a semiquantitative approach (focal versus diffuse type of leakage). Retinal arteriovenous passage (AVP) times were measured using dye dilution curves and digital image analysis for each hemisphere. The number of defective visual field points (StatPac: p<0.5%, uncorrected deviation plot) were evaluated (30/2 SITA, Humphrey-Zeiss) for the hemifields and different sectors. RESULTS: In this study of patients with NAION the mean AVP was 1.79 s±0.43 which was not significantly correlated to the number of defective points. Furthermore, AVP was not significantly different in focal versus diffuse optic disc leakage. The number of defective points were not significantly different in focal versus diffuse leakage of the optic disc (p=0.57). CONCLUSION: Retinal perfusion is not linked to the type and topography of disc leakage or the extent and topography of visual field damage in NAION. A global circulatory disorder e.g. due to a compartment syndrome of the optic nerve might account for these results.

[Sensitivity of imaging the peripheral nerve fibre layer using a confocal scanning laser ophthalmoscope to detect glaucoma]. / Sensitivität der Nervenfaserdarstellung mittels Scanning Laser Ophthalmoskop bei Glaukom.

PURPOSE: The aim of this study was to evaluate the sensitivity to detect glaucoma by observer-dependent nerve fibre layer imaging and evaluation using a scanning laser ophthalmoscope. PATIENTS AND METHODS: Fifty-four patients with primary open angle glaucoma (POAG), 41 patients with normal tension glaucoma (NTG) and 65 eyes of control subjects were included in a retrospective study. Nerve fibre layer imaging was performed using a confocal scanning laser ophthalmoscope (SLO, Rodenstock Instr., argon laser 488 nm). Digitised images of the nerve fibre layer were graded off-line by two masked experienced observers. The nerve fibre layer was graded for every single degree (defect or no defect) at 1.7 and 3.4 mm distance to the optic nerve head omitting the nasal 110 degrees. Sensitivity and specificity levels were calculated using ROC analysis. RESULTS: Patients with POAG exhibited nerve fibre layer defects of 100 degrees +/- 94 degrees (1.7 mm and 3.4 mm distance) and patients with NTG of 94 degrees +/- 94 degrees (1.7 mm distance) and 103 degrees +/- 92 degrees (3.4 mm distance), significantly larger compared to controls (1 degrees +/- 3 degrees [1.7 mm, p < 0.0001] and 1 degrees +/- 4 degrees [3.4 mm, p < 0.0001]). Sensitivity at > 90 % specificity was 80 % (1.7 mm) and 82 % (3.4 mm) for POAG. In NTG, sensitivity at > 90 % specifity was 81 % (1.7 mm) and 85 % (3.4 mm). In early glaucoma (MD < -6 dB, n = 39) sensitivity decreased to 75 % (1.7 mm) and 81 % (3.4 mm). CONCLUSION: Observer-dependent evaluation and grading of the nerve fibre layer using a scanning laser ophthalmoscope reaches considerably high sensitivity levels to detect glaucoma with negligible differences between the central and peripheral regions.

Performance of colour Doppler imaging discriminating normal tension glaucoma from healthy eyes.

PURPOSE: Previous studies have shown decreased retrobulbar blood flow in normal tension glaucoma (NTG) compared to healthy controls. This study evaluates the ability of colour Doppler imaging (CDI) to identify patients with NTG. METHODS: Sixty-two patients with untreated NTG (mean age 57+/-14 years) and 40 age-matched controls (mean age 58+/-9 years) were included in a prospective cross-sectional institutional study. Peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistive indices (RI=(PSV-EDV)/PSV) of the ophthalmic artery (OA), central retinal artery (CRA), and short posterior ciliary arteries (PCAs) were measured by means of CDI. Using receiver operating characteristic (ROC) curves, sensitivity was determined at 90% specificity. RESULTS: Patients with NTG showed significantly decreased PSV (P<0.0001) and EDV (P<0.0001) of the CRA, significantly decreased EDV of the nasal (P=0.004) and temporal (P=0.002) PCA, and significantly increased RI of the temporal (P=0.003) PCAs compared to healthy controls. Sensitivity values at 90% specificity were calculated: PSV of the CRA, 30.6%; EDV of the CRA, 48.4%; EDV of the nasal PCA, 43.9%; EDV of the temporal PCA, 45.9%; and RI of the temporal PCA, 39.3%. CONCLUSIONS: The power to identify NTG using CDI reaches 48% sensitivity at 90% specificity. Further longitudinal studies are needed to determine the prognostic value of CDI in glaucoma.

Amniotic membrane transplantation in severe ocular surface disorders.

PURPOSE: Amniotic membrane transplantation is currently being used as an alternative approach to treat severe corneal surface disorders refractory to medical therapy. The authors report complications of corneal surface disorders after successful amniotic membrane transplantation. METHODS: Case series. RESULTS: Twenty-eight patients with corneal surface disorders due to severe chemical burns, corneal ulceration, or persistent epithelium defects were treated with amniotic membrane transplantation. Four of these patients showed a spontaneous perforation and three patients developed a descemetocele within 6 weeks after the amniotic membrane transplantation. CONCLUSIONS: In this case series, descemetocele and corneal perforation occurred in 25% of the patients after amniotic membrane transplantation. This might be due to the severity of the underlying disease or to the impact of amniotic membrane on corneal fibroblasts and collagenases. The risk of corneal thinning and perforation should be considered in the decision of treatment with amnion and follow-up regimen.

Retrobulbar haemodynamics and morphometric optic disc analysis in primary open-angle glaucoma.

BACKGROUND: Previous studies confirmed reduced retrobulbar haemodynamics in primary open-angle glaucoma (POAG). AIM: To investigate a correlation between retrobulbar haemodynamics and morphometric neuroretinal rim analysis in patients with POAG. METHODS: 51 patients with POAG (mean (standard deviation (SD)) age 65 (11) years) were included in this clinical study. Blood flow velocities (peak systolic velocity (PSV) and end-diastolic velocity (EDV)) of the ophthalmic artery, central retinal artery (CRA), posterior ciliary arteries (PCA) and central retinal vein were measured using colour Doppler imaging (Siemens Sonoline Sienna, Erlangen, Germany). Optic disc morphometry was carried out using scanning laser tomography (Heidelberg Retinal Tomograph II Heidelberg Egineering Heidelberg, Germany). The stereometric parameters of the neuroretinal rim (rim area, rim volume, cup shape measure and retinal nerve fibre layer (RNFL) cross-sectional area) were used for analysis. RESULTS: The PSV of the CRA was significantly (p<0.001) correlated with rim area (r = 0.50) and rim volume (r = 0.51). The minimum velocities of the central retinal vein were significantly (p<0.001) correlated with rim volume (r = 0.56) and RNFL cross-sectional area (r = 0.49). No correlations were found for the flow velocities of the ophthalmic artery and PCAs. CONCLUSION: Retrobulbar haemodynamics of the central retinal artery and vein are correlated with the neuroretinal rim damage in POAG.

Retrobulbar haemodynamics in non-arteritic anterior ischaemic optic neuropathy.

AIM: To compare retrobulbar haemodynamics in patients with acute non-arteritic anterior ischaemic optic neuropathy (NAION) and age-matched controls by colour Doppler imaging (CDI). METHODS: 25 patients with acute NAION and 35 age-matched controls participated in this study. By means of CDI, the blood flow velocities of the ophthalmic artery, central retinal artery (CRA), and nasal and temporal short posterior ciliary arteries (PCAs) were measured. Peak-systolic velocity (PSV) and end-diastolic velocity (EDV) and Pourcelot's resistive index were determined. RESULTS: In the ophthalmic artery, no marked differences between patients with NAION and controls were detected. PSV and EDV of the CRA (p<0.001, p = 0.002) and PSV of the nasal PCA (p<0.05) were significantly decreased in patients with NAION compared with healthy controls. No marked differences between patients and controls were detectable for temporal PCAs. CONCLUSION: Blood flow velocities of the nasal PCA and the CRA are considerably reduced in patients with acute NAION compared with controls. Patients with NAION in part showed markedly different retrobulbar haemodynamics.

[Colour Doppler imaging in normal pressure glaucoma patients]. / Doppler-Sonographie bei Normaldruckglaukompatienten.

AIM: Ocular hemodynamics is of great interest in glaucoma, especially since vascular disturbances may play a pathogenetic role in disease development. To investigate the hemodynamic differences between normal pressure glaucoma patients and normal volunteers, flow velocities of the retrobulbar vessels were measured by colour Doppler imaging. METHOD: 15 patients with normal pressure glaucoma (NPG) and 15 healthy volunteers underwent colour Doppler imaging (CDI) of the retrobulbar vessels. The patients and the volunteers were especially gender- and age-matched. Peak systolic velocities (PSV), end-diastolic velocities (EDV), and resistive indices (RI) of the ophthalmic artery and central retinal artery were obtained. RESULTS: In NPG patients, PSV and EDV in the central retinal artery were significantly decreased, whereas RI was increased in central retinal artery and the ophthalmic artery. CONCLUSION: Colour Doppler imaging is a non-invasive technique that allows further estimation of the ocular circulatory status. Particularly in the group of patients with disturbed hemodynamics, like NPG patients, it was able to show a reduction of the retrobulbar hemodynamics.

24-h blood pressure monitoring in normal tension glaucoma: night-time blood pressure variability.

Systemic arterial hypotension, hypertension and altered ocular blood flow are known risk factors in glaucoma. In this study, 24-h ambulatory blood pressure monitoring was performed in patients with normal tension glaucoma (NTG) and controls to evaluate blood pressure variability. In all, 51 patients with NTG and 28 age-matched controls were included in this prospective study. A 24-h ambulatory blood pressure monitoring (SpaceLabs Medical Inc., Redmond, USA) was performed and systolic, diastolic and mean arterial blood pressures were measured every 30 min during daytime (0800-2000) and night time (0000-0600). To evaluate blood pressure variability a variability index was defined as the s.d. of blood pressure measurements. Night-time blood pressure depression ('dip') was calculated (in percent of the daytime blood pressures). Patients with NTG exhibited higher night-time diastolic (P = 0.01) and mean arterial blood pressure values (P = 0.02) compared to controls, whereas systolic blood pressure data were not significantly different. The variability indices of night-time systolic, diastolic and mean arterial blood pressure measurements were significantly increased in patients with NTG compared to controls (P < 0.05). The night-time blood pressure depression of systolic (P = 0.47), diastolic (P = 0.11) and mean arterial blood pressures (P = 0.28) was not significantly different between patients with NTG and controls. In conclusion, patients with NTG showed increased variability of night-time blood pressure measurements compared to controls. Increased fluctuation of blood pressure may lead to ocular perfusion pressure fluctuation and may cause ischaemic episodes at the optic nerve head.

Colour Doppler imaging before and after retrobulbar anaesthesia in patients undergoing cataract surgery.

PURPOSE: To investigate the effect of retrobulbar anaesthesia on retrobulbar haemodynamics, colour Doppler imaging was performed. Furthermore, the additive effect of epinephrine was examined. METHOD: Forty-one patients (age 72.7+/-8.9; 22 f, 19 m) undergoing planned cataract surgery were included in a prospective study. Colour Doppler imaging was performed before and directly after retrobulbar anaesthesia and after cataract surgery to measure the peak systolic velocity (PSV) and end-diastolic velocity (EDV) in the ophthalmic artery, central retinal artery and central retinal vein. In 18 patients lidocaine 2% without additives (2 ml, retrobulbar transconjunctival injection) and in 23 patients lidocaine 2% with epinephrine 1:200,000 was used. RESULTS: After retrobulbar anaesthesia both groups had a significant reduction of the PSV and of the EDV. After surgery flow velocities increased again. The addition of epinephrine resulted in a significantly greater reduction and slower recovery of flow velocities. CONCLUSION: Retrobulbar anaesthesia induces a marked reduction of velocity in the retrobulbar vessels. The supplement epinephrine increases this effect, and recovery is much slower. Thus, particularly in patients with already disturbed ocular haemodynamics epinephrine should not be used in order to avoid irreversible functional damage.

Effect of retrobulbar versus subconjunctival anaesthesia on retrobulbar haemodynamics.

AIM: To investigate the effect of retrobulbar and subconjunctival anaesthesia on retrobulbar haemodynamics by colour Doppler imaging. METHOD: 39 patients (mean age 71 (SD 9) years; 19 females, 20 males) undergoing planned cataract surgery were included in the prospective study. Colour Doppler imaging (Siemens Sonoline Sienna, Germany) was performed before, directly after either subconjunctival (16 patients) or retrobulbar (23 patients) anaesthesia, and after cataract surgery to measure the peak systolic (PSV) and end diastolic velocities (EDV) in the ophthalmic artery (OA), central retinal artery (CRA), and central retinal vein (CRV). RESULTS: After retrobulbar anaesthesia there was a significant reduction of the PSV and of the EDV in all investigated vessels. After surgery the flow velocities increased again. Subconjunctival anaesthesia had no significant effects on retrobulbar haemodynamics. CONCLUSION: Retrobulbar anaesthesia induces a high reduction of velocity in the retrobulbar vessels in contrast with subconjunctival anaesthesia. Therefore subconjunctival anaesthesia should be preferred particularly in patients with problems of the ocular perfusion (for example, glaucoma).

Blue on yellow perimetry with scanning laser ophthalmoscopy in patients with age related macular disease.

BACKGROUND/AIM: The loss of short wavelength sensitive (SWS) cone mechanism sensitivity is related to severe vision loss in patients with age related maculopathy (ARM). A case-control study of patients with ARM and age matched controls was performed, using blue on yellow static perimetry. METHODS: A bright yellow background at 594 nm isolated the responses of short wavelength cone mechanisms to 458 nm targets. A scanning laser ophthalmoscope produced stimuli and provided real time, simultaneous fundus illumination. The macula was probed with 16 Goldmann IV targets, 1-10 degrees from fixation, using a staircase method. RESULTS: 24 patients with non-exudative ARM were matched to 24 subjects with normal fundus appearance. SWS cone pathway sensitivity for macular targets was significantly reduced in the patients with ARM compared to normals--15.45 (SD 4.56) dB v 17.22 (0.28) dB, respectively (p<0.0005). There was not only a diffuse loss of sensitivity in ARM patients, but also a localised loss of sensitivity over drusen (p<0.025). Neither the mean age, 69 (8) years, nor the mean visual acuity differed between groups, logMAR 0.09 (0.10) v 0.05 (0.06) for ARM patients v normals, respectively. Patients with soft drusen had lower sensitivity than those with hard drusen (p<0.05). CONCLUSION: A loss of SWS cone pathway sensitivity occurred in most patients with early ARM, despite good visual acuity, demonstrating a loss of visual function that cannot be attributed to ageing changes. The loss of sensitivity, despite good visual acuity, included both a diffuse loss and localised losses.

[Recurrence of a retrobulbar neuritis? Classic VEP and missing periocular pain]. / Rezidiv einer Retrobulbärneuritis? Klassisches VEP und fehlender Bewegungsschmerz.

BACKGROUND: In young patients with the clinical symptoms of a neuritis neuroradiological imaging is not always necessary. This case report describes a young patient who suffered from a recurrence after 5 years. Since all findings, particularly visual evoked potentials, were classic for neuritis, the patient was treated for neuritis although periocular pain was not present. CASE REPORT: Five years after a neuritis of the left eye (OS), the patient was again referred with a visual loss (VA 0.3 OS). In addition to an afferent pupillary defect OS and a constricted visual field OS, an inter-eye latency difference was demonstrated in the visually evoked potentials. The patient was treated with megadose steroid therapy. Although periocular pain as a classic symptom was absent, no neuroradiological imaging was performed. Six weeks later visual acuity and visual fields further worsened, such that a nuclear magnetic resonance imaging was indicated revealing a meningioma fronto-basally compressing the optic nerve. After neurosurgical intervention visual acuity and field stabilized. CONCLUSIONS: In rare cases, meningioma may mimic the symptoms of neuritis. Therefore, neuroradiological imaging is indicated in recurrences or complicated disease courses, particularly if classic symptoms such as periocular pain are missing.

[Defect closure with scleral grafts]. / Defektverschluss mit Sklerainterponaten.

BACKGROUND: Excessively draining fistulas may lead to enucleation when primary suture closure is not effective. In these cases preserved cadaver tissues such as sclera, fascia lata, dura mater and peritoneum have been used for patch graft repair with variable results. In this study, the clinical outcomes after transplantation of scleral patch grafts have been investigated. METHOD: Twenty-eight eyes of twenty-seven patients underwent surgery with homologous scleral patch grafts for repair of excessively draining scleral fistulas after cataract surgery (n = 2), leaking filtering blebs following full-thickness filtration surgery (n = 7), large scleral perforations due to trauma (n = 7), corneo-scleral ulcerations due to severe eye burns (n = 9) or after radiotherapy of malignant melanoma (n = 3). The mean size of the rectangular grafts was 8.6 x 6.7 mm (+/- 2.8/3.1 mm). Clinical follow-up was up to 73 months (median 30 months). RESULTS: Twenty-three of 28 eyes (82.1 %) showed functional closure after initial surgery without any wound complication such as patch retraction or leakage and without evidence of inflammation. In five eyes surgical revision was necessary. Two of these eyes had to be enucleated due to uncontrollable dehiscence after the second operation. Two eyes were enucleated at the patient's demand due to pain. The fifth eye showed effective closure after the second operation. CONCLUSION: In our study scleral patch grafts were useful in adequately closing large corneo-scleral defects in 24 of 28 eyes (85.7 %). The antigen load and, therefore, the rejection of the scleral grafts is minimized due to the denaturation of proteins during the alcohol treatment before storage.

Comparison of colour Doppler imaging and retinal scanning laser fluorescein angiography in healthy volunteers and normal pressure glaucoma patients.

PURPOSE: To correlate retinal circulatory measurements using scanning laser fluorescein angiography and flow velocities of retrobulbar vessels measured by means of colour Doppler imaging. METHODS: Fifteen patients with normal pressure glaucoma (NPG) and 15 healthy volunteers underwent colour Doppler imaging and fluorescein angiographic studies. Peak systolic velocities (PSVs), end-diastolic velocities (EDVs) and resistive indices (RIs) of the ophthalmic artery (OA) and central retinal artery were obtained. In the fluorescein angiograms arteriovenous passage time (AVP) was quantified by means of digital dye dilution curve analysis. RESULTS: Arteriovenous passage time was significantly prolonged in NPG patients compared to healthy subjects (p = 0.0026). In the central retinal artery PSV (p = 0.023) and EDV (p < 0.0001) were significantly decreased and RI was increased (p < 0.0001) in patients with NPG. The EDV of the central retinal artery showed a significant correlation with AVP (EDV: r = - 0.53, p = 0.0023). The RI of the central retinal artery correlated significantly to AVP (RI: r = 0.63, p < 0.0001). The AVP did not correlate to EDV or PSV, nor to the RI measured in the ophthalmic artery. CONCLUSION: Arteriovenous passage time, which represents blood flow in a vascular segment of artery, capillary bed and corresponding vein, was found to be correlated to the EDV and the RI of the central retinal artery. The combination of different techniques allows further interpretation of ocular circulatory responses.

Effects of brinzolamide on ocular haemodynamics in healthy volunteers.

AIM: A prospective, randomised study to evaluate effects of brinzolamide on ocular haemodynamics in healthy volunteers. METHODS: 30 volunteers (12 men, 18 women; 28.3 (SD 7.8) years) were prospectively randomised to either brinzolamide or placebo during a 2 week double masked treatment trial. Examinations were performed at baseline and after 2 weeks of treatment. Intraocular pressure was measured and automatic static perimetry (Humphrey field analyser, 24-2) and contrast sensitivity (CSV 1000, Vector Vision) were performed. Retrobulbar blood flow velocities (peak systolic and end diastolic velocity) and resistive indices (RI) of ophthalmic artery, central retinal artery and of temporal and nasal short posterior ciliary arteries were measured by colour Doppler imaging (Sonoline Sienna Siemens). In video fluorescein angiograms (scanning laser ophthalmoscope, Rodenstock) arteriovenous passage time (AVP, dilution curves) and peripapillary diameters of retinal arterioles and venules were measured by means of digital image analysis. RESULTS: Intraocular pressure was significantly decreased by brinzolamide (p<0.0001). Neither brinzolamide nor placebo changed visual field global indices after treatment. Contrast sensitivity at 3 cycles per degree was significantly higher in the placebo group (p<0.05). Apart from an increase of RI in ophthalmic artery under placebo treatment (p<0.05) there was no effect in retrobulbar haemodynamics in both groups. Brinzolamide therapy alone resulted in a significant reduction of AVP compared to baseline (p<0.05), while peripapillary retinal vessels diameters remained unaffected. CONCLUSIONS: Apart from the expected decrease of intraocular pressure brinzolamide showed no significant change in retrobulbar haemodynamics, but a significant shortening of AVP. Since in glaucoma AVP is prolonged indicating vascular dysfunction this effect might be beneficial in glaucoma therapy.

Colour Doppler imaging and fluorescein filling defects of the optic disc in normal tension glaucoma.

AIM: To investigate the relation between blood flow parameters of the retrobulbar vessels measured by means of colour Doppler imaging (CDI) and fluorescein filling defects of the optic nerve head in patients with normal tension glaucoma (NTG) and control subjects. METHODS: 29 patients with NTG and 29 age and sex matched control subjects were included in this study. Blood flow velocities-peak systolic velocity (PSV), end diastolic velocity (EDV), and resistive indices (RI) of the ophthalmic artery (OA), the central retinal artery (CRA), and of the temporal and nasal short posterior ciliary arteries (TPCA, NPCA)-were measured with CDI. Fluorescein angiograms were performed with a scanning laser ophthalmoscope. The extent of absolute fluorescein filling defects of the optic nerve head in relation to the optic nerve head was assessed. RESULTS: The PSV of the OA, the PSV and EDV of the CRA, and of the TPCA and NPCA were significantly reduced in NTG (p<0.05). The RI of the CRA, the TPCA and NPCA were significantly increased in NTG (p<0.01). The optic nerve head fluorescein filling defects were significantly larger in NTG (p<0.01). The filling defects were significantly negatively correlated (p<0.05) with the PSV and EDV of the CRA (PSV(CRA): r = -0.41; EDV(CRA): r = -0.34), with the PSV and EDV of the NPCA (PSV(NPCA): r = -0.34; EDV(NPCA): r = -0.38), and with the EDV of the TPCA (r = -0.29). A significant positive correlation (p<0.05) was found with the RI of both PCAs (RI(NPCA): r = 0.28; RI(TPCA): r = 0.29). CONCLUSION: Patients with NTG had reduced blood flow velocities and higher resistive indices in most retrobulbar vessels. Optic nerve head fluorescein filling defects were larger compared to controls. The filling defects were correlated with end diastolic velocities and resistive indices of the PCAs and with blood flow velocities of the CRA. Capillary loss of the optic nerve head may be related to higher downstream resistance and reduced blood flow velocities of the retrobulbar vessels.