Vitrified before and after genome editing via electroporation.

BACKGROUND: Cryopreservation of bovine zygotes allows for a flexible schedule of genome editing via electroporation. However, vitrification-induced cell membrane damage may not only affect embryonic development but also genome mutation. OBJECTIVE: To investigate the effects of vitrification of zygotes before and after electroporation treatments on the development and genome mutation of bovine presumptive zygotes. MATERIALS AND METHODS: In vitro-derived bovine zygotes were electroporated with the CRISPR/Cas9 system immediately (Vitrified-EP) or 2 h after incubation (Vitrified-2h-EP) following vitrification and warming, or electroporated before vitrification (EP-vitrified). RESULTS: The development rates of vitrified-warmed zygotes were significantly lower (p < 0.05) than those of control zygotes that were not vitrified. Moreover, no differences were observed in the mutation rates and mutation efficiency of the blastocysts resulting from electroporated zygotes, irrespective of the timing of electroporation treatment. CONCLUSION: Our results suggest that vitrification before and after electroporation treatments does not affect the genome editing of zygotes.

Effects of nilvadipine, a calcium antagonist, on rabbit ocular circulation and optic nerve head circulation in NTG subjects.

PURPOSE: To study the effects of nilvadipine, a Ca2+ antagonist, on tissue circulation in the optic nerve head (ONH), choroid, and retina in rabbits and on the ONH circulation in normal tension glaucoma (NTG) patients. METHODS: Nilvadipine (3.2 microg/kg) or vehicle solution was injected intravenously into urethane-anesthetized rabbits, and the normalized blur value (NB), a quantitative index of in vivo tissue blood velocity, was measured in the choroid and in an area of the ONH and retina free of visible surface vessels before and for 90 minutes after injection, using the laser speckle method. The effects of nilvadipine on the ONH circulation was also studied using the H2 gas clearance method in separate groups of rabbits. Oral nilvadipine (4 mg/d) or placebo was administered to NTG patients in a double-masked manner, and NB in an area of the ONH rim free of visible surface vessels was measured by the same method before and 2, 4, 8, and 12 weeks after administration. RESULTS: The NB obtained from the ONH, choroid, or retina during the experimental period was increased by approximately 10% to 25% in the nilvadipine group compared with the NB in the control group (P < 0.0001, ANOVA), although systemic condition parameters and intraocular pressure (IOP) showed no significant intergroup difference except for a transient decrease in blood pressure in the nilvadipine groups. Blood flow rate in the ONH determined by the H2 gas clearance method also showed an approximately 25% increase in the nilvadipine group. The NB in the ONH of the oral nilvadipine-treated patients was significantly increased, by approximately 20% compared with the placebo-treated patients throughout the follow-up period. No significant intergroup difference was seen in blood pressure, pulse rate, or IOP. CONCLUSIONS: Nilvadipine increased blood velocity and, probably, blood flow in the ONH, choroid, and retina of rabbits. It also increased blood velocity in the ONH of NTG patients.

Effects of topical latanoprost on optic nerve head circulation in rabbits, monkeys, and humans.

PURPOSE: To evaluate the effect of topically administrated latanoprost on optic nerve head (ONH) circulation in Dutch rabbits, cynomolgus monkeys, and normal humans. METHODS: The ONH tissue blood velocity (NB(ONH)) was determined using the laser speckle method. Latanoprost (0.005%, 30 microl) was instilled into one eye, and vehicle into the other eye as a control. In rabbits, NB(ONH) was measured for 90 minutes after a single instillation and before and after a 7-day once-daily instillation regimen. In monkeys, NB(ONH) was measured before and after 1, 4, and 7 days of a once-daily instillation regimen. The effect of intravenous indomethacin on the latanoprost-induced NB(ONH) change was also studied in rabbits and monkeys. In humans, the time-course changes in NB(ONH) were measured for 4.5 hours before and after a 7-day once-daily instillation regimen. Intraocular pressure (IOP) and systemic parameters were simultaneously studied in each experiment. All measurements were performed by investigators masked to the experimental condition. RESULTS: Latanoprost significantly increased NB(ONH) 10% to 19% in treated eyes after a single instillation (P = 0.035) or 7-day instillation regimen (P = 0.035) in rabbits, after a 4-day (P = 0.035) or 7-day (P = 0.035) instillation regimen in monkeys, and after a 7-day (P = 0.013) instillation regimen in humans, whereas there were no significant changes in the vehicle-treated eyes in any of the experiments (P > 0.5). Pretreatment with indomethacin (5 mg/kg) abolished the NB(ONH) increase but not the IOP reduction in latanoprost-treated eyes in rabbits and monkeys. IOP remained unchanged in both eyes in rabbits (P > 0.4), whereas it significantly decreased only in latanoprost-treated eyes in monkeys (P < 0.05) and humans (P < 0.05). CONCLUSIONS: Topical latanoprost significantly increased ONH blood velocity only in treated eyes in rabbits, monkeys, and humans. This effect was independent of the IOP-reducing effect of latanoprost and probably was associated with local penetration of the drug and the production of endogenous prostaglandins.

Effects of topical adrenergic agents on tissue circulation in rabbit and human optic nerve head evaluated with laser speckle tissue circulation analyzer.

The effects of topical adrenergic agents on the tissue circulation of the optic nerve head (ONH) were studied in animal and human eyes with use of a laser speckle tissue circulation analyzer. Drugs studied were nipradilol, a beta1-2-blocker with weak alpha-blocking and nitroglycerinlike activities; bunazosin, a selective alpha1-blocker; carteolol, a beta1-2-blocker with intrinsic sympathomimetic activity; and betaxolol, a selective beta1-blocker. In the animal experiment, one eye each of nine albino rabbits received 0.25% nipradilol (N = 9) twice daily for 15 days or 0.01% bunazosin (N = 10) twice daily for 20 days; the fellow eye received the vehicle of each drug in a randomized masked design. Normalized blur (NB) in an area of ONH free of visible surface vessels, a quantitative index of peripheral blood velocity in ONH, was measured under general anesthesia before treatment and 2 hours after the last instillation on the 15th or 20th day. At 15 days, intraocular pressure and NB in the nipradilol-treated eyes decreased by 4.3 mm Hg (P < 0.01) and increased by 15.9% (P < 0.01), respectively, while those in the vehicle-treated eyes showed little change. At 20 days NB in both bunazosin- and vehicle-treated eyes showed little change, while intraocular pressure decreased only in the bunazosin-treated eyes (P < 0.01). In the human volunteer experiment NB was averaged over five pulses (mean NB) in both eyes before and 1.5, 3.0 and 4.5 hours after a 30 microL instillation of the vehicle of carteolol or betaxolol to serve as a control. Intraocular pressure, blood pressure and pulse rate were also measured. One week later a 30 microL drop of 2.0% carteolol (N = 6) or 0.5% betaxolol (N = 10) was instilled in one randomly chosen eye and the vehicle for each drug in the other eye, and those parameters were measured as above in a double-masked manner. In the carteolol experiment, mean NB in both eyes was significantly higher at 3 hours than it was in the control experiment (P < 0.05), while intraocular pressure was significantly lower in both eyes and blood pressure and pulse rate showed little change. In the betaxolol experiment, intraocular pressure at 1.5 hours and blood pressure at 4.5 hours were significantly lower than those in the control experiment (P < 0.05), while mean NB and pulse rate showed little change. In summary, using the laser speckle method we found that topical nipradilol and carteolol increase ONH blood velocity in rabbits and humans, respectively. This finding suggests that some topical beta-blockers used clinically may influence the ONH tissue circulation in patients and that this method may be used in clinical situations to assess the effect of various drugs on ONH circulation.

Retrobulbar circulation in myopic patients with or without myopic choroidal neovascularisation.

AIM: To investigate the effect of myopia and myopic choroidal neovascularisation (CNV) on retrobulbar circulation in central retinal artery (CRA) and vein (CRV) and posterior ciliary artery (PCA). METHODS: 52 subjects with and without myopia were included in the study. Retrobulbar circulation was measured using colour Doppler imaging. Analysis of correlation of degree of myopia with blood flow velocity parameters was done. Circulatory differences between eyes of patients with unilateral neovascular degenerative myopia were estimated. RESULTS: The analysis of correlation between dioptry and blood flow velocity in the CRA, CRV, and PCA showed a significant positive correlation. Axial length was also significantly correlated with CRA and CRV blood velocity and had a tendency to be correlated with PCA blood velocity. When compared with the fellow eye, the eye with myopic CNV had significantly higher resistivity index (RI) (p=0.048) in the PCA and no significant difference in the circulatory parameters of the CRA and CRV. CONCLUSION: Central retinal and posterior ciliary blood velocity decreases with the increase of the degree of myopia. PCA RI is higher in myopic CNV.

Effects of scleral buckling and encircling procedures on human optic nerve head and retinochoroidal circulation.

AIMS: To study the effects of segmental scleral buckling and encircling procedures on tissue circulation in the human optic nerve head (ONH) and choroid and retina. METHODS: Using the laser speckle method, the normalised blur (NB) value, a quantitative index of tissue blood velocity, was measured every 0.125 seconds and averaged over three pulses in the optic nerve head (NB(ONH)) and choroid and retina (NB(ch-ret)) in 10 patients with unilateral rhegmatogenous retinal detachment (mean age 52 (SD 17)). NB(ONH), NB(ch-ret), and intraocular pressure (IOP) in both eyes, and blood pressure (BP) were measured before, and 1, 4, and 12 weeks after the scleral buckling and encircling procedure. RESULTS: NB(ch-ret) on the buckled side was significantly reduced after surgery and smaller than that in the unoperated contralateral eye throughout the study period (ANOVA, p<0.0001). NB(ch-ret) on the unbuckled side, in the foveal area, NB(ONH), IOP, and BP showed no significant change. CONCLUSIONS: It was indicated that the segmental scleral buckling procedure with encircling elements decreased tissue blood velocity in the choroid and retina on the buckled side but caused no significant change on tissue circulation in other areas of the fundus or ONH.

Relation between retrobulbar circulation and progression of diabetic retinopathy.

AIMS: To investigate retrobulbar circulatory parameters in type 2 diabetic patients with and without diabetic retinopathy (DR) progression. METHODS: This was a prospective cohort study. One eye of 35 diabetic patients with background DR (BDR) were included in the study. Eyes without DR, with proliferative DR, photocoagulation, past surgical procedures, or other ophthalmic disease except BDR and cataract were excluded. The study was masked. Colour Doppler imaging (CDI) was used to measure the retrobulbar circulation at the beginning of the study and after a mean follow up interval of 21 months. Peak systolic velocity (PSV), end diastolic velocity (EDV), and resistivity index (RI) in the central retinal artery and vein and the posterior ciliary artery were measured. RESULTS: 18 patients who developed DR progression showed significantly increased central retinal vein PSV ( 5.6 (3.5-9.1) p = 0.003), EDV ( 3.4 (2.3-4.4) p = 0.04), and RI ( 0.43 (0.20-0.56) p = 0.02) at the final measurement compared to the initial measurement (PSV = 4.6 (3.2-7.0); EDV = 3.0 (2.3-3.7); RI = 0.40 (0.17-0.52)). Circulatory parameters in the central retinal artery and the posterior ciliary artery did not alter significantly after progression of DR. 17 patients were without DR progression and they did not show any significant differences in the measured circulatory parameters on entry compared to the final measurement. CONCLUSION: The authors suggest that the initial changes in the retrobulbar circulation during DR progression occur in the central retinal vein.

Effect of topical beta-blockers on tissue blood flow in the human optic nerve head.

PURPOSE: To study the effect of topical 0.5% timolol and 2% carteolol on tissue blood flow in the human optic nerve head (ONH). METHODS: Using a laser speckle tissue blood flow analyzer, normalized blur (NB), a quantitative index of tissue blood velocity, was measured every 0.125 s in the temporal site of the ONH free of visible surface vessels and averaged over 3 cardiac pulses (NBONH). To serve as a baseline, NBONH and intraocular pressure (IOP) in both eyes, blood pressure (BP) and pulse rate (PR) were recorded in healthy volunteers before, 1.5, 3 and 4.5 hrs after a 30L instillation of the vehicle of timolol or carteolol. From the following day and twice daily for 3 weeks, 30L of either 0.5% timolol or 2% carteolol was instilled into one eye and the respective vehicle into the fellow eye in a masked manner. NBONH, IOP, BP and PR were again recorded on the 21st and last experiment day. IOP was also recorded on the 7th and 14th days. Carteolol concentration in the plasma was also recorded after instillation of carteolol on the 21st day. RESULTS: During the baseline experiments, all the parameters recorded showed no significant change. After topical timolol, IOP was significantly reduced bilaterally with more reduction in the timolol-treated eye. Bilateral NBONH, BP and PR showed little change on the 21st day. After topical carteolol, IOP was significantly reduced bilaterally with more reduction in the carteolol-treated eyes on the 21st day. NBONH in the carteolol- and vehicle-treated eyes was significantly higher on the 21st day than recorded in the same eye in the baseline experiment (P = 0.013 and 0.047), while BP and PR showed little change. The maximum carteolol concentration in plasma at 3 hrs on the 21st day averaged 1294 pg/ml. CONCLUSIONS: Results indicated that 3-week twice daily topical timolol treatment had no deleterious effect on the ONH tissue blood flow in the human eye, and that 3-week twice daily topical carteolol treatment may increase the tissue blood flow in the human ONH.

Effect of topical betaxolol on tissue circulation in the human optic nerve head.

There have been no reports to date on long-term betaxolol instillation effects on the human optic nerve head (ONH) tissue circulation. The purpose of this study was to study the effect of topical 0.5% betaxolol on tissue blood velocity in the human ONH. Using a laser-speckle tissue blood flow analyzer, normalized blur (NB; a quantitative index of tissue blood velocity) was measured every 0.125 seconds at a temporal ONH site free of visible surface vessels. Measurements were averaged for 3 cardiac cycles (NB(ONH)). For baseline comparison (day 0), recordings of bilateral NB(ONH) and intraocular pressure (IOP), blood pressure (BP) and pulse rate (PR) were recorded in healthy volunteers before, and 2, 4.5, and 7 hr after, instillation of 30 microL of betaxolol vehicle, and again on day 21; IOP was also recorded on days 7 and 14. On day 1 (the day after baseline measurements), and twice daily for 3 weeks, 30 microL of 0.5% betaxolol into one eye and 30 microL vehicle was instilled into the other in a double-blind study. Measurements as on day 0 were again recorded on day 21; IOP was also recorded on days 7 and 14. During baseline recordings, no significant changes were noted in any parameters. After administration of topical betaxolol, IOP was significantly reduced, bilaterally, with greater reduction in the betaxolol-treated eyes on day 21. Also on day 21, the NB(ONH) of the betaxolol-treated eyes was significantly higher 4.5 hr after instillation than that of the comparable baseline recording (p = 0.035 with Bonferroni's correction); BP, PR, and NB(ONH) in the eye which received only the vehicle showed little change. Tissue blood velocity in the human ONH was increased at least temporarily by instillation of topical betaxolol twice daily for 3 weeks. Although the obtained increase is small and may be clinically insignificant, the potential of betaxolol that can affect the ONH tissue circulation in humans after 21 days of instillation is thought to deserve further investigation.

Protective efficacy of sodium hyaluronate on the corneal endothelium against the damage induced by sonication.

The protective efficacy of sodium hyaluronate (Na-HA) on the corneal endothelium against the damage induced by sonication was investigated using enucleated rabbit eyes and Na-HA fluorescence labeled with 5-aminofluorescein (FA-HA). The anterior chamber was reformed by injecting a 1% solution of FA-HA, and then sonication, irrigation and aspiration were performed in the anterior chamber using a phaco-needle attached to phacoemulsification and aspiration (PEA) equipment. The protective efficacy was evaluated by the area of damaged corneal endothelium. When the anterior chamber was reformed by the solution of FA-HA with a molecular weight of 2010 x 10(3) (FA-HA (2010 x 10(3) group), most of the FA-HA was eliminated within 20 seconds after starting the irrigation and aspiration, and the area of damaged endothelium was the same with the case when the FA-HA was not pre-injected (Control group). On the other hand, when the anterior chamber was reformed by the solution of FA-HA with a molecular weight of 1130 x 10(3) (FA-HA (1130 x 10(3) group), the FA-HA was gradually eliminated after mixing with an irrigating solution, and the area of damaged endothelium was significantly smaller than those of the Control and FA-HA (2010 x 10(3)) groups. These results suggest that the corneal endothelial damage induced by PEA can be avoided by pre-injecting a viscoelastic material which can remain in the anterior chamber during PEA.

Topical latanoprost and optic nerve head and retinal circulation in humans.

The purpose of the present study was to study the effect of a single instillation of latanoprost on the human optic nerve head (ONH) and retinal circulation. Using laser-speckle tissue blood flow analysis, normalized blur (NB; a quantitative index of tissue blood velocity) was measured every 0.125 sec at a temporal ONH site free of visible surface vessels. Measurements were averaged for 3 cardiac cycles (NB(ONH)). Color Doppler Imaging (CDI) was also used to evaluate peak systolic blood velocity (PSV), endo-diastolic velocity (EDV), and resistive index (RI) in the central retinal artery (CRA) and mean blood velocity (MV) in the central retinal vein (CRV). One drop of 0.005% latanoprost was instilled into one eye and its vehicle into the other in eleven healthy volunteers in a double-blinded manner. Measurements of bilateral NB(ONH), CDI parameters, intraocular pressure (IOP), blood pressure (BP), and pulse rate (PR) were performed before, and 45, 90, 180, and 270 min after instillation. After a single instillation of latanoprost or the vehicle, there was no significant bilateral difference throughout the experimental period. The difference in NB(ONH) between that before and at each time point of measurement (delta NB(ONH)) in the latanoprost-treated eyes was significantly higher between 45 and 270 min after instillation than that in vehicle-treated eyes (P = 0.0003 to 0.0156); ANOVA for repeated measurements also revealed significant difference between both eyes (P < 0.00001). BP, PR, and NB(ONH) in the eye that received only the vehicle, PSV, EDV, and RI in the CRA in both eyes, and MV in the CRV in both eyes changed little. Tissue blood velocity in the ONH increased at least temporarily following a single instillation of topical latanoprost. Although the mechanism of the increase is unclear, the effects of latanoprost on ONH tissue circulation in humans may have clinical implications.

Effect of topical unoprostone on circulation of human optic nerve head and retina.

The purpose of the present study was to study the effect of topical unoprostone on the circulation of human optic nerve head (ONH) and retina in normal subjects. Using laser-speckle tissue blood flow analysis, normalized blur (NB), a quantitative index of tissue blood velocity, was measured every 0.125 sec at a temporal ONH site, free of visible surface vessels. Measurements were averaged for 3 cardiac cycles (NB(ONH)). Color Doppler imaging (CDI) was also used to evaluate peak systolic blood velocity (PSV), end-diastolic velocity (EDV), and resistive index (RI) in the central retinal artery (CRA) and mean blood velocity (MV) in the central retinal vein (CRV). For baseline comparison (Day 0), recordings of bilateral NB(ONH) and intraocular pressure (IOP), blood pressure (BP), and pulse rate (PR) were recorded in healthy volunteers before, and 45, 90, 180, and 270 min after instillation of one drop of unoprostone vehicle. On Day 1 (the day after baseline measurements), and twice daily for 7 days, one drop of 0.12% unoprostone was instilled into one eye and its vehicle into the other in a double-blinded manner. Measurements as on Day 0 were recorded on Days 1 and 7. CDI measurements were performed before and at 45 and 180 min after morning instillation on Days 1 and 7. During baseline recordings, there were no significant changes in any parameters. After administration of topical unoprostone, IOP was significantly lower bilaterally with more reduction in the unoprostone-treated eyes on Day 7. On Day 7, the NB(ONH) of the unoprostone-treated eyes was significantly higher 45 min after instillation than baseline (P = 0.035 with Bonferroni's correction). Analysis of variance for repeated measurements also revealed significant difference between Day 0 and Day 7 (P = 0.0017). BP, PR, NB(ONH) in the eye that received only the vehicle, PSV, EDV, and RI in the CRA in both eyes, and MV in the CRV in both eyes changed little. Tissue blood velocity in the ONH increased, at least temporarily, following instillation of unoprostone twice daily for 7 days. Although the clinical implication of the increase is unclear, the effects of topical unoprostone on human ONH circulation deserve further consideration.

Blood velocity in the ophthalmic artery determined by color Doppler imaging in normal subjects and diabetics.

Color Doppler imaging was used to analyze the blood velocity in the ophthalmic artery (BVA) of 33 normal subjects and 36 diabetic patients. Maximum systolic BVA (Vmax), minimum end-diastolic BVA (Vmin) and Pourcelot index (RI: index of vascular resistance) were determined by analyzing the pulse wave of flow velocity in the ophthalmic artery. The coefficient of reproducibility of Vmax, Vmin and RI in normal subjects was 10%, 9% and 4%, respectively, when analyzed twice at one-hour intervals. There was no significant difference in the indices of the right eyes compared to those of the left eyes. The averages of Vmax, Vmin and RI were 25.4 +/- 7.6 cm/s, 6.3 +/- 2.3 cm/s and 0.75 +/- 0.052 (mean +/- SD), respectively. Vmax and Vmin decreased significantly with age (Vmax: r = -0.65, P < 0.001; Vmin: r = -0.61, P < 0.001). RI did not change with age. Vmax, Vmin and RI were compared between normal subjects and patients. RI was significantly higher in diabetics (0.775 +/- 0.047 in patients without retinopathy, 0.779 +/- 0.084 in patients with background retinopathy and 0.786 +/- 0.081 in patients with preproliferative or proliferative retinopathy) than in normal subjects (0.728 +/- 0.054). This suggests there is a pathological increase in choroidal vascular resistance and/or a decrease in the diameter of the ophthalmic artery in diabetics.

Real-time blood velocity measurements in human retinal vein using the laser speckle phenomenon.

PURPOSE: To measure the in vivo blood velocity in human retinal veins using a laser speckle system. METHODS: The system consists of a fundus camera, a diode laser, an image sensor, and a personal computer system. The fundus area, including a target retinal vein, is illuminated with a diode laser through a fundus camera and the laser speckle pattern is imaged onto the area sensor. From the time change of the contrast of the speckle pattern, the normalized blur (NB) value, a quantitative index of blood velocity, was calculated using a logic board. RESULTS: In an in vitro experiment, the NB obtained from blood flow in 50-300 microm internal diameter glass capillary tubes, used as an analogue of a retinal vein, correlated with the diameter of the tube, the actual blood flow rate, and the background NB value, which was used as an analogue of choroidal circulation. In the in vivo experiment, the blood velocity in human retinal veins of approximately 50 microm in diameter was estimated in 16 normal human eyes using nomograms based on the result of the in vitro experiment. Velocity averaged 11.1+/-0.6 mm/s (mean +/- SD, n = 16) in retinal veins 53+/-6 microm in diameter. The coefficient of reproducibility of 5-minute interval measurements was 2.5+/-0.9%, and it took 63+/-15 seconds for one measurement. CONCLUSIONS: The present methodology is clinically valid for measuring blood velocity in retinal veins.

Two cases of frosted branch angiitis with central retinal vein occlusion.

BACKGROUND: Frosted branch angiitis usually occurs in children, and has a good prognosis. We report two cases of unilateral frosted branch angiitis in adults. Both had poor visual outcomes because of associated central retinal vein occlusion and neovascular glaucoma. CASES: Case 1 was a 36-year-old woman. Almost all retinal veins and some retinal arteries showed vasculitis in her right eye, and veins were slightly dilated and sheathed. Case 2 was a 23-year-old woman. Angle hypopyon was observed in her left eye. Retinal veins were dilated, meandering, and sheathed. Retinal hemorrhages were also observed. In both cases, after systemic steroid therapy the retinal vasculitis gradually decreased, but central retinal vein occlusions gradually developed. Despite systemic administration of urokinase and panretinal photocoagulation, neovascular glaucoma developed, and visual acuity diminished in both cases. CONCLUSIONS: Two cases of frosted branch angiitis complicated by retinal vein occlusion are reported. Careful observation of retinal blood flow is necessary in frosted branch angiitis in adults.

Real-time measurement of human optic nerve head and choroid circulation, using the laser speckle phenomenon.

A modification of a previously described instrument that used the laser speckle phenomenon for noncontact two-dimensional analysis of the fundus tissue circulation was devised so that tissue circulation in the optic nerve head (ONH) or choroid of the human eye could be measured on a real-time basis. The fundus was illuminated by a diode laser spot and the image speckle was recognized by an area sensor. A quantitative index of blood velocity, normalized blur (NB), was calculated by a logistic board every 0.125 seconds for 7 seconds. Using this modified device, the average NB of the measurement field in the temporal ONH, free of visible surface vessels (NBONH), and that in the posterior choroid (NBch) of normal human eyes were measured. The coefficients of reproducibility of 1-minute interval measurements were 11.7% for the NBONH) and 8.7% for the NBch (each, an average of 5 pulses), and those of 24-hour interval measurements were 13.0% (NBONH) and 9.7% (NBch). The pulsatile component average of NBONH was 38.4% of mean NBONH; of NBch, 26.6% of the mean NBch.

Comparison of severity of acquired renal cysts between CAPD and hemodialysis.

The prevalence and severity of renal cystic changes in 15 continuous ambulatory peritoneal dialysis (CAPD) patients were compared with those in 15 hemodialysis patients matched by age, sex and duration of dialysis. Cyst grade and kidney volume were prospectively evaluated using CT scan. In 15 age- and sex-matched patients on long-term dialysis, follow-up for a mean of 32 months, beginning 73 months after the start of dialysis, revealed that, in both treatment modalities, a significant increase in cyst grade, kidney volume and the rate of increase in kidney volume as a reflection of cystic change (3.08 +/- 3.87 [mean +/- SD] ml/month in CAPD, 1.43 +/- 1.17 ml/month in hemodialysis) had occurred. However, differences in these parameters between CAPD and hemodialysis groups were not significant. In 7 patients in the CAPD group who were also treated by hemodialysis, it could not be statistically proven that the rate of increase in kidney volume during initial hemodialysis was different from that observed in subsequent CAPD (2.60 +/- 2.44 ml/month during hemodialysis, 5.13 +/- 4.94 ml/month during CAPD). This longitudinal prospective study suggests that the prevalence and severity of acquired renal cystic disease are the same in long-term CAPD and hemodialysis patients.

[Analysis of blood flow velocity in the ophthalmic artery by color Doppler imaging. 2. Studies on diabetic eyes].

Color Doppler imaging was used to investigate the changes in Pourcelot index (RI), which is an index for vascular resistance calculated from the blood flow velocity of the ophthalmic artery, related to the complications of diabetes mellitus (diabetic retinopathy, diabetic nephropathy) and systemic background (duration of diabetes mellitus, value of hemoglobin A1C (HbA1c)) in 46 diabetic patients and in 20 normal subjects. RI was significantly higher in diabetic patients than in normal subjects (p < 0.05). RI increased in patients without retinopathy (p < 0.05), in patients with background retinopathy (p < 0.05), and in patients with preproliferative or proliferative retinopathy (p < 0.05), but it did not change in patients after panretinal photocoagulation, compared with the normal subjects. In diabetic patients, RI was higher (p < 0.05) in patients with nephropathy than in those without nephropathy. The time from onset of diabetes mellitus and the value of HbA1c had no correlation with RI. Our results indicate that choroidal circulation was changed in diabetic patients compared with normal subjects and that the changes were related to diabetic nephropathy.

[Measurements of blood flow velocity in human retinal veins using laser speckle flowgraphy system].

We measured the blood flow velocity in human retinal veins using a laser speckle flowgraphy system. This system consists of a fundus camera, a diode laser, an image sensor and a personal computer system. The fundus is illuminated with a diode laser through a fundus camera and the laser speckle pattern is imaged onto the area sensor. From the time change of contrast of speckle pattern, normalized blur (NB) value, a quantitative index of tissue blood velocity, was calculated by means of a logistic board, and two-dimensional distribution of NB in the measurement field was displayed in a color display. In the in vitro experiment, the NB obtained from the blood flow in a glass capillary tube was correlated with the diameter of the tube, background NB value and the blood flow rate actually measured. In the in vivo experiment, the blood velocity in human retinal veins of approximately 50 microns in diameter was estimated in 16 normal eyes using nomograms based on the results of the in vitro experiment. Velocity averaged 11.1 +/- 0.6 mm/ sec (mean +/- standard deviation, n = 16) in retinal veins of 53 +/- 6 microns in diameter and the reproducibility index of the in vivo measurements was 2.5 +/- 0.9%.

[Analysis of blood flow velocity of ophthalmic artery with color Doppler imaging. 1. Studies on normal human eyes].

Color Doppler imaging was used to analyze the blood flow velocity of the ophthalmic artery (BVA) by measuring the pulse wave of flow velocity in the ophthalmic artery of normal subjects. Maximum systolic BVA (Vmax), minimum end-diastolic BVA (Vmin), time-averaged BVA (Vmean), Pourcelot index (RI) and pulsatility index (PI) were determined using color Doppler imaging. The coefficients of reproducibility of Vmax, Vmin, Vmean, RI and PI were 10%, 9%, 15%, 4% and 14%, respectively, when analyzed twice at one-hour intervals. There was no significant difference between the values of the right eye and that of the left eye in each case. The averages of Vmax, Vmin, Vmean, RI and PI of 33 normal eyes were 25.4 +/- 7.6 cm/sec, 6.3 +/- 2.3 cm/sec 16.7 +/- 6.6 cm/sec, 0.75 +/- 0.052, 1.19 +/- 0.25 (mean +/- S.D.), respectively, Vmax, Vmin and Vmean decreased significantly with age (Vmax:linear correlation coefficient r = -0.65, p < 0.001; Vmin: r = -0.61, p < 0.001, r = -0.64, p < 0.001. RI did not change with age. PI increased significantly with age (r = 0.30, p < 0.05).