Corneal endothelial cells' protection against thermal injury: influence of ophthalmic viscoelastic substances in experimental study on rabbits.

PURPOSE: To quantify the maximal level of temperature and the time the maximal temperature is achieved and correlate the temperature parameters to the mean rate of endothelial cell loss after standardized ultrasound delivery assisted with four viscoelastic substances or different temperature of balanced salt solution (BSS). METHODS: Thirty rabbits (60 eyes) were divided into six groups in which different viscoelastic substances or different temperature of BSS were used: Group 1, Viscoat; 2, Provisc; 3, soft shell technique; 4, Celoftal; 5, BSS 22 degrees C; and 6, BSS 4 degrees C. The same parameters of ultrasound energy were delivered by standard phaco tip introduced into pupillary plane. Thermocamera was employed for measurements of temperature parameters. Endothelium cell count was measured before surgery and 1 month postoperatively. RESULTS: Maximal level of temperature was measured as follows: Group 5, 27.85 +/- 0.52 degrees C; Group 2, 27.75 +/- 0.54 degrees C; Group 3, 27.74 +/- 0.46 degrees C; Group 4, 27.25 +/- 0.60 degrees C; Group 6, 26.81 +/- 0.34 degrees C; Group 1, 26.52 +/- 0.48 degrees C (p<0.05). The time the maximal temperature is achieved was statistically shorter in Groups 5 and 6: 4 seconds, 5 seconds, respectively, p<0.0001, as compared with Group 2 (30 seconds), Group 3 (40 seconds), Group 1 (45 seconds), and Group 4 (50 seconds). The mean rate of endothelial cell loss was calculated as follows: Group 1, 4.35%+/-2.55%; Group 2, 8.43%+/-5.2%; Group 3, 6.25%+/-4.20%; Group 4, 6.53%+/-4.65%; Group 5, 14.3%+/-3.85%; and Group 6, 8.78%+/-4.45%. CONCLUSIONS: Viscoelastic substances offer different levels of endothelial cell protection against temperature increase during phacoemulsification. The mean rate of endothelial cell loss correlates with the time the maximal temperature is achieved rather than with the value of maximal level of temperature. This implicates that surgical strategy should consider the choice of the most effective viscoelastic substances, particularly in difficult cases, e.g., hard nucleus, shallow anterior chamber, primary endothelial abnormality.

Corneal endothelial cells' protection against thermal injury: influence of ophthalmic viscoelastic substances in experimental study on rabbits.

PURPOSE: To quantify the maximal level of temperature and the time the maximal temperature is achieved and correlate the temperature parameters to the mean rate of endothelial cell loss after standardized ultrasound delivery assisted with four viscoelastic substances or different temperature of balanced salt solution (BSS). METHODS: Thirty rabbits (60 eyes) were divided into six groups in which different viscoelastic substances or different temperature of BSS were used: Group 1, Viscoat; 2, Provisc; 3, soft shell technique; 4, Celoftal; 5, BSS 22 C; and 6, BSS 4 C. The same parameters of ultrasound energy were delivered by standard phaco tip introduced into pupillary plane. Thermocamera was employed for measurements of temperature parameters. Endothelium cell count was measured before surgery and 1 month postoperatively. RESULTS: Maximal level of temperature was measured as follows: Group 5, 27.85 0.52 C; Group 2, 27.75 0.54 C; Group 3, 27.74 0.46 C; Group 4, 27.25 0.60 C; Group 6, 26.81 0.34 C; Group 1, 26.52 0.48 C (p<0.05). The time the maximal temperature is achieved was statistically shorter in Groups 5 and 6: 4 seconds, 5 seconds, respectively, p<0.0001, as compared with Group 2 (30 seconds), Group 3 (40 seconds), Group 1 (45 seconds), and Group 4 (50 seconds). The mean rate of endothelial cell loss was calculated as follows: Group 1, 4.35%2.55%; Group 2, 8.43%5.2%; Group 3, 6.25%4.20%; Group 4, 6.53%4.65%; Group 5, 14.3%3.85%; and Group 6, 8.78%4.45%. CONCLUSIONS: Viscoelastic substances offer different levels of endothelial cell protection against temperature increase during phacoemulsification. The mean rate of endothelial cell loss correlates with the time the maximal temperature is achieved rather than with the value of maximal level of temperature. This implicates that surgical strategy should consider the choice of the most effective viscoelastic substances, particularly in difficult cases, e.g., hard nucleus, shallow anterior chamber, primary endothelial abnormality.

[The influence of the hormonal replacement therapy on the amount and stability of the tear film among peri- and postmenopausal women]. / Wplyw hormonalnej terapii zastepczej na wydzielanie i stabilnosc filmu lzowego u kobiet w okresie okolo- i pomenopauzalnym.

PURPOSE: To estimate the amount of the tear-film and its stability among women treated due to endocrinological or gynecological indications with hormone replacement therapy. MATERIAL AND METHODS: 60 women treated with hormonal replacement therapy (HRT) were divided into 3 groups of examination: group 1 (20 women), treated with HRT after up to 1 year of menopausal symptoms, group 2 (20 women) treated with HRT between 1-5 years of menopausal symptoms, group 3 (20 women) treated with HRT after more than 5 years of menopausal symptoms. The secretion of the tear-film was measured using Schirmer I test and lisozyme test. The stability of the tear-film was measured with respect to the break-up time (BUT). The examinations were performed 3, 6, 12 months after HRT treatment. The values obtained before HRT treatment served as control. RESULTS: Before HRT treatment we observed significantly decreased tear secretion and lower stability in group 2 and group 3 as compared with group 1. We noticed the negative correlation between the secretion of the tear film as compared to age of examined women. HRT made the tear secretion significantly increased in group 2 and group 3 after 6, 12 and 3, 6, 12 months of HRT treatment respectively. We assessed a significant improvement of the tear film stability with respect to BUT in group 2 and 3 in all months of HRT treatment. We found significant correlation between modified Schirmer I test and lisozyme test (p < 0.001). CONCLUSION: The age and changes of the hormonal homeostasis have negative influence on the tear secretion, tear-film stability among peri and postmenopausal women. HRT treatment has beneficial influence on the tear film secretion and tear stabilization. Our results suggest that hormonal replacement therapy can be suitable for the treatment of the postmenopausal dry eye syndrome.

[The influence of the hormonal replacement therapy on conjunctival epithelium morphology among peri- and postmenopausal women]. / Wplyw hormonalnej terapii zastepczej na stan morfologiczny komórek nablonka spojówki u kobiet w okresie okolo- i pomenopauzalnym.

PURPOSE: To estimate the status of the conjunctival morphology among women treated due to endocrinological or gynecological indications with hormone replacement therapy. MATERIAL AND METHODS: 60 women treated with hormonal replacement therapy (HRT) were divided into three groups of examination: group 1 (20 women), treated with HRT after up to 1 year of menopausal symptoms, group 2 (20 women) treated with HRT between 1-5 years of menopausal symptoms, group 3 (20 women) treated with HRT after more than 5 years of menopausal symptoms. The morphology of the conjunctival epithelium was assessed by impressive cytology. The examinations were performed 3, 6, 12 months after HRT treatment. The values obtained before HRT treatment served as control. RESULTS: The preliminary examinations showed changes of the morphology of conjunctival epithelium in all groups. The longer duration of postmenopausal period, the more advanced morphological changes. In all groups of examinations the HRT has the beneficial influence on the state of conjunctival epithelium morphology. CONCLUSION: The age and changes of the hormonal homeostasis have negative influence on conjunctival epithelium morphology among peri- and postmenopausal women. HRT treatment has beneficial effect on the conjunctival epithelium morphology. Our results suggest that hormonal replacement therapy can be suitable for prevention and treatment of postmenopausal conjunctival changes.

[Assessment of nitric oxide level in aqueous humor under physiological conditions and after lens extraction with PMMA during experimental work in rabbits]. / Ocena stezenia tlenku azotu w cieczy wodnistej w warunkach fizjologicznych oraz po usunieciu soczewki i wszczepie sztucznej soczewki z PMMA w badaniach doswiadczalnych u królika.

PURPOSE: To evaluate the presence of nitric oxide and measure its level in the aqueous humor of the rabbit's eye, in physiological conditions and after extracapsular lens extraction and PMMA artificial lens implantation. We also investigated nitric oxide maintenance during early postoperative period (between 1-5 day after surgery). MATERIAL AND METHODS: We used 30 rabbits (weighing 3.0-3.5 kg) Just before surgery samples of aqueous humor were aspirated by anterior chamber puncture. Lens was extracted with extracapsular (envelope) technique. In 15 eyes PMMA IOL was implanted in the bag and 15 eyes were left aphakic. The aqueous samples were collected on 1st, 3rd, 5th days after surgery. Nitric oxide in each sample was measured with respect to fluorometric assay. RESULTS: In aqueous humor in physiological conditions we detected nitric oxide. Its level was estimated on the value of 26.52 nM/dl. After extracapsular lens extraction in both groups the level of nitric oxide was significantly higher than in control group. The day and value of NO level was different among examined groups. Nitric oxide level diminished significantly on 5th postoperative day. CONCLUSION: We came to conclusion that after ECCE and PMMA IOL implantation NO level was significantly higher as compared with control. This higher NO level after lens extraction can be responsible for the blood aqueous breakdown.

[Assessment of nitric oxide level in aqueous humor under physiological conditions and after lens extraction and artificial foldable acrylic lens implantation during experimental work in rabbits]. / Ocena stezenia tlenku azotu w cieczy wodnistej w warunkach fizjologicznych oraz po usunieciu soczewki i wszczepie sztucznej zwijalnej soczewki akrylowej w badaniach doswiadczalnych u królika.

PURPOSE: To evaluate the presence of nitric oxide (NO) and its level in the aqueous humor of rabbit's eye physiological conditions and after phacoemulsification and acrylic foldable artificial lens implantation. We also investigated nitric oxide maintenance during early postoperative period (between 1-5 days after surgery). MATERIAL AND METHODS: We examined 30 rabbits (weighing 3.0-3.5 kg) Just before surgery samples of aqueous humor were aspirated. Lens was extracted with phacoemulsification technique. In 15 eyes acrylic foldable IOL (group III) was implanted and 15 eyes were left aphakic (group IV). The aqueous samples were collected on 1, 3, 5 days after surgery. Nitric oxide in each sample was determined with fluorometric assay. RESULTS: The level of NO in aqueous humor in physiological conditions was estimated to 26.52 nM/dl. After phacoemulsification in both groups the level of nitric oxide was higher than in control group. The day and value of the highest NO level was different among examined groups. The highest level of NO was released during 1st day in group III and on the 3rd day in the group IV. CONCLUSION: We came to conclusion that the level of nitric oxide in aqueous humor after phacoemulsification in both groups is higher than in control group but significantly lower than in previously examined groups in which the surgery was made with extracapsular technique.

[Direct measurement of nitric oxide levels in aqueous humor with selective iso-NO electrode under physiologic conditions and after phacoemulsification and artificial acrylic lens implantation in experiments on rabbits]. / Bezposredni pomiar stezenia tlenku azotu w cieczy wodnistej selektywna elektroda pomiarowa Iso-NO w warunkach fizjologicznych oraz po fakoemulsyfikacji i wszczepie sztucznej akrylowej soczewki w badaniach doswiadczalnych u królika.

PURPOSE: Using a direct method, with selective and nitric oxide sensitive electrode Iso-NO, we estimated the level of the Nitric Oxide (NO) in the aqueous humor of the rabbit's eye after phacoemulsification and acrylic foldable lens implantation. We also analysed the NO level during early postoperative days between the 1st and the 5th postoperative day. The current methods of the NO level estimations are also considered. MATERIAL AND METHODS: We examined 30 gray rabbits (weighing 3.0-3.5 kg). Just before surgery, samples of aqueous humor were aspirated. Lens was extracted with phacoemulsification technique. In 15 eyes acrylic foldable IOL was implanted and 15 eyes were left aphacic. The aqueous samples were collected 1, 3, 5 days after surgery. Nitric oxide in each sample was determined with direct, selective nitric oxide sensitive electrode Iso-NO. Because of changing values of the NO concentration and its characteristic course, we expressed the concentration of NO in aqueous humor using field-under-curve method to compare it with control group. The results of our examination are presented in the absolute values. RESULTS: During physiological conditions the mean value of the field under curve of the NO concentration was estimated as 4987.29 +/- 895.89. After phacoemulsification with or without artificial lens implantation the level of the NO was higher as compared to the control group. After phacoemulsification and acrylic foldable lens implantation the highest level of NO was estimated on the 1st postoperative day as 6917.10 +/- 1199.72. During the examinations, the field under curve of NO concentration was estimated as 6246.63 +/- 327.02 and 5172.28 +/- 552.67 (on the 3rd and 5th days respectively). Only on the 1st and the 3rd postoperative day, the value of the field under curve of NO was significantly higher as compared with the control group. In contrast, after phacoemulsification without lens implantation the highest value of NO field under curve, was estimated on the 3rd postoperative days as 5801.44 +/- 344.45. During the examinations, the field under curve of NO concentration was estimated as 5115.30 +/- 796.11 and 4837.12 +/- 205.87 (on the 1st and the 5th days, respectively). Moreover, it was the only one day of examination with significantly higher value of NO field under curve as compared with the control. CONCLUSION: We came to conclusion that the level of nitric oxide in aqueous humor after phacoemulsification with or without artificial lens implantation is higher than in control group. The highest value of the field under curve was estimated on the 1st postoperative day after phacoemulsification and acrylic foldable lens implantation and on the 3rd postoperative day after phacoemulsification without lens implantation.

[Direct measurement of nitric oxide levels in aqueous humor with selective iso-NO electrode under physiologic conditions and after extracapsular cataract extraction and artificial lens implantation with PMMA in experiments with rabbits]. / Bezposredni pomiar stezenia tlenku azotu w cieczy wodnistej, selektywna elektroda pomiarowa Iso-NO w warunkach fizjologicznych oraz po zewnatrztorebkowym usunieciu soczewki i wszczepie sztucznej soczewki z PMMA w badaniach doswiadczalnych u królika.

PURPOSE: To estimate the level of the nitric oxide (NO) within the aqueous humor of the rabbit eye after ECCE and PMMA artificial lens implantation using selective, nitric oxide sensitive electrode Iso-NO. We analysed the NO level during early postoperative period between the 1st and the 5th day. MATERIAL AND METHODS: We examined 30 gray rabbits (weighing 3.0-3.5 kg). Just before surgery, samples of aqueous humor were aspirated to control the NO level in physiological condition. Lens was extracted with ECCE (envelope) technique. In 15 eyes PMMA IOL were implanted and 15 eyes were left aphacic. The aqueous samples were also collected 1, 3, 5 days after surgery. Nitric oxide in each sample was estimated directly with selective, nitric oxide sensitive electrode Iso-NO. Changing values of the NO concentration during the examination were expressed using evaluation of field under curve in the absolute values. Such results were compared with control group. RESULTS: During physiological conditions the mean value of the field under curve of the NO concentration was estimated as 4987.29 +/- 895.89. After ECCE with or without PMMA artificial lens implantation the levels of the NO were higher as compared to the control group. After ECCE and PMMA artificial lens implantation the highest level of NO was estimated on the 3rd postoperative day (7978.98 +/- 949.77). During the examinations the fields under curve of NO concentration were estimated as 6626.30 +/- 1176.53 and 6288.19 +/- 604.90 (on the 1st and the 5th days, respectively). On all postoperative days, values of the field under curve of NO were significantly higher as compared to the control group. In contrast, after ECCE without lens implantation the highest value of NO field under curve, was estimated on the 1st postoperative day as 11727.83 +/- 1032.44. During the examinations, the fields under curve of NO concentration were estimated as 9841.52 +/- 698.06 and 5446.96 +/- 568.47 (on the 3rd and the 5th postoperative days, respectively). Moreover, on all days of examination the value of NO fields under curve were significantly higher as compared to the control group. CONCLUSION: The level of nitric oxide in aqueous humor after ECCE with or without artificial lens implantation was higher than in the control group. The highest value of the field under curve was estimated on the 3rd postoperative day after ECCE and PMMA artificial lens implantation and on the 1st postoperative day after ECCE without lens implantation. The use of direct selective electrode Iso-NO is a simple method of nitric oxide estimation in aqueous humor, but the interpretation of results seems to be very difficult. This method may be suitable for comparative estimations of NO during the experimental works.

[Use of keratoprosthesis type "champagne cork"--case report]. / Zastosowanie keratoprotezy typu "korek od szampana"--opis przypadku.

Kerathoprosthesis application is limited to strictly definite indications such as: after a severe corneal scald, after repeated graft rejections or temporarily just before the intricate eye operation to expose the posterior segment. Considerable progress in this province has been observed since PMMA were introduced. Recently a new successful method of "champagne cork" kerathoprosthesis, described firstly by Worst, has been reported. It is designed as a reverse cone and in comparison with other models provides significantly wider range of vision and simultaneuosly better visibility of fundus, which are the main advantages of this prosthesis. In our case this pattern of prosthesis was implanted in general anaesthesis and 24 hours after operation the visual acquity was 3/50. The insight into fundus was too blurred to assess fundus details. After 48 hours the haemorrhage to corpus vitreum appeared and after 3 months without clot absorption the decision was made to extract it by pars plana vitrectomy. In local anaesthesis the operation was performed with 3 typical entrance incisions, and clots that formed non-transparent membrane on the cone together with involved corpus vitreum were removed. After 24 hours visual acquity was 5/50 and corpus vitreum and retina could be assessed through an anterior segment. It seems that this type of kerathoprosthesis should be widely recommended.

Changes in the structure and properties of corpus vitreous and the preservation of enzymatic composition of rabbit antioxidative system under the influence of sulphur hexafluoride gas.

PURPOSE: To evaluate clinical, physiochemical and biochemical changes in rabbit vitreous body caused by local injection of sulphur hexafluoride gas. MATERIAL AND METHODS: The volume of fluid vitreous fraction was measured with Na+, K+, Mg2+, Ca2+ levels and full proteins concentration in both vitreous fractions in 24 New Zealand rabbits at 2, 7 and 14 day after SF6 injection. The activity of superoxide dismutase, catalase and malonyl dialdehyde were used to evaluate the activity of antioxidative enzymatic system. Control group consisting of 6 New Zealand rabbits had no experimental procedures. RESULTS: In the investigated group, the fluid vitreous fraction volume was increased while gelatous one was diminished from 0.08 ml in control group to 0.32 ml in the study group (on day 14). The level of Na+, K+, Mg2+, Ca2+ in the fluid fraction was unchanged. On day 7, we noticed statistically significant increase in protein concentration in comparison with the control group and the study group on 14 day. The activity of superoxide dismutase and catalase as well as the level of malonyl dialdehyde were increased in the fluid vitreous fraction compared to the gelatous one in the control group. After the SF6 injection we did not observe any changes of superoxide dismutase and catalase activities in the gelatous part of vitreous body while in the fluid one there was statistically significant decrease in the enzymatic activity and the MDA level in the whole observation time. CONCLUSIONS: The injected sulphur hexafluoride gas caused the damage of the gelatous vitreous fraction with the increase in the fluid one. The oxygen free radicals might trigger these pathological processes.

Influence of rectus eye muscles tenotomy on the aqueous humor composition in rabbits.

INTRODUCTION: Anterior segment ischaemia manifesting in aqueous malformation may follow tenotomy of the extraocular muscles. MATERIAL AND METHODS: Tenotomy of 2 or 4 rectus eye muscles was performed on the right eyes of 23 adult rabbits. The aqueous humor was withdrawn from the anterior chamber of both eyes in 7 rabbits on the 11th, on the 22nd in 8 and on the 32nd postoperative day in 8 rabbits. Aqueous natrium, potassium and glucose concentrations and protein electrophoresis were examined. RESULTS: The only significant change was lower mean aqueous potassium concentration in the operated eyes as compared to controls on the 11th postoperative day. CONCLUSION: Tenotomy of rectus eye muscles in healthy rabbits evoked a discrete blood-aqueous barrier break-down.

[The physical and chemical changes in the eye structure after sulfurhexafluoride injection into the rabbit vitreous]. / Zmiany fizyczne i chemiczne w strukturach galki ocznej po podaniu szesciofluorku siarki do ciala szklistego królików.

AIM: The aim of our paper was to observe the physical and chemical changes in the aqueous humor, lens, gelatous and fluid part of the vitreous body after the sulfurhexafluoride injection into the vitreous body. MATERIAL AND METHODS: The New Zealand rabbits were randomized into the control and experimental group which were injected the gas into the vitreous body. The interesting samples were investigated during the 2nd, 7th and 14th day of the experiment. We estimated the volume of the fluid part of the vitreous body, its electrical resistance, the whole protein concentration (in the aqueous humor, lens and vitreous), and electrolite concentration (in the aqueous humor and fluid part of the vitreous body). RESULTS: We observed the increase of the fluid fraction in the vitreous body with the increasing of the whole protein concentration, changes in the K+ concentration and decrease of the electrical resistance in the vitreous fluid fraction. CONCLUSION: On the basis of our experimental results we can assume that expanding sulfurhexafluoride gas could mechanically disrupt the vitreous structure. Moreover, the rapid intrabulbar pressure increase after the injection can cause the cilliary body ischaemia and the eye barrier collapse.

[Lacrimation disorders in workers chronically exposed to petroleum derivatives]. / Zaburzenia wydzielania lez u pracowników narazonych na przewlekle oddzialywanie pochodnych ropy naftowej.

Lacrimal fluid plays a very significant role in maintaining proper functions of conjuctivas, cornea and eyelids. The fluid is secreted by the main lacrimal gland and additional glands. It produces the so called preocular lacrimal film. A number of clinical tests, such as Chirmer's tests I and II, break-up-time (BUT), lysozyme, and flow tests are used in quantitative and qualitative analyses, as well as in the determination of the lacrimal film stability. The aim of work was to utilize these in assessing the lacrimal secretion and the lacrimal film stability in workers chronically exposed to petroleum derivatives. Fifty three workers from departments of acetobenzene, benzene and butadiene, phenol and acetone, sewage waters, asphalt oxidas, polyethylene and polypropylene, were eligible for the study (group I). During previous examinations, acquired disorders in colour perception were diagnosed in all the subjects by means of the Mansuella-Fansworth 100-Hue test. The age range was 25 to 56 years, with a mediane of 44.1 years +/- 6.5. Mean duration of employment was 22 years (SD +/- 8.25). The control group (group II) was composed of 28 men aged between 24 and 60 years with a median of 42.7 years +/- 6.3, never employed under conditions of exposure to toxic chemicals. On the right eye of each subject Schirmer's test was performed after instilling into the conjunctival sac 1-2 drops of Alcain solution according to Whitcher. Five min following anesthesia of the conjunctival sac, a standardised belt of blotting-paper with colour dampness markers Vidisic (Dr Mann Pharma GMBH, Germany) was placed in the vicinity of the external angle of the eye. After 5 min the degree of the belt dampness was measured in millimetres. After 30 min the break-up-time test was performed on the left eye. Fluorescein was released to conjunctival sac from a sterile belt of blotting-paper (Haag-Strait Co.). A slit lamp with cobalt filter was used to calculate time (in sec) that elapsed between opening of the lid slit and the first symptom of breaking-up the lacrimal film. The results obtained were presented in the form of arithmetic means and standard deviation values +/- SD. Schirmer's test was 13.40 +/- 7.43 mm in group 1, and 22.54 +/- 8.25 mm in the control group, mean values differed significantly, p < 0.01. Lacrimal film break-up-time was 16.30 +/- 6.19 sec in group 1, and 31.48 +/- 7.96 sec in the control group, mean values differed significantly, p < 0.01. In persons chronically exposed to petroleum derivatives, statistically significant decrease in lacrimal secretion, as well as shortening of lacrimal film break-up-time were found when compared with the control group.

[Changes in the antioxidant system of the vitreous in rabbits after administration of sulfur hexafluoride]. / Zmiany w ukladzie antyoksydacyjnym ciala szklistego królików po podaniu szesciofluorku siarki.

PURPOSE: To evaluate the enzymatic activity of antioxidant system of rabbit's vitreous after sulfur hexafluoride (SF6) application. MATERIAL AND METHODS: Activity of CuZn-SOD, catalase and concentration of MDA in fluid and gel fraction of vitreous were determined in 24 rabbits of New Zealand race on the 2nd, 7th and 14th day after SF6 application. Control group consisted of 6 animals which did not undergo any operations. RESULTS: Dismutase and catalase activity as well as MDA concentration were higher in fluid fraction than in gel fraction in animals of control group. After SF6 application the activity of enzymes and MDA concentration did not change, whereas in fluid fraction all these values were statistically significantly reduced in all time intervals. CONCLUSIONS: SF6 leads to disintegration of vitreous structure especially just after its application. Damage to hyalocytes causes dysfunction of enzymatic system. Specific fluid fraction structure and insufficient number of substrates for peroxidation processes are the reasons for simultaneous reduction of MDA concentration.

[Changes in the antioxidant system of the aqueous humor, lens and erythrocytes after sulfur hexafluoride application to the vitreous of rabbits]. / Zmiany w ukladzie antyoksydacyjnym cieczy wodnistej, soczewce i krwinkach czerwonych krwi obwodowej po podaniu szesciofluorku siarki do ciala szklistego królików.

AIM: To determine the activity of superoxide dismutase, catalase and the concentration of malondialdehyde (MDA) in aqueous humor, lens and red blood cells after application of sulfur hexafluoride (SF6) into vitreous of rabbits. MATERIAL AND METHODS: 0.5 ml of 100% SF6 was injected into the vitreous of 24 rabbits of New Zealand race. The animals were randomly divided into 3 groups (of 8 rabbits each) depending on the observation day: group 1-2nd day of experiment, group 2-7th day and group 3-14th observation day. The control group (gr. 0) consisted of 6 rabbits that did not undergo any operations. Activity of superoxide dismutase, catalase and MDA concentration were determined in aqueous humor, lens and systemic blood erythrocytes. RESULTS: On the 7th day of observation an increased activity of dismutase and catalase as well as simultaneous increased MDA concentration were observed. In the lens on the 7th day the increased activity of dismutase was significant in relation to the results in the next time interval, whereas MDA concentration was significantly lower in all time intervals of the experiment in comparison with control group. In erythrocytes an increased activity of catalase was noticed on the 2nd and 14th day. CONCLUSIONS: Increased occurrence of active oxygen species in aqueous humor leads to insufficiency of the antioxidant system and intensification of peroxidation processes, which is reflected by increased MDA concentration. However, in the lens of this experimental model a slight stimulation of antioxidant system by a small number of free radicals is observed, which provokes a reaction of sweeping them away. Efficiency of lens antioxidant system is secured by weakening of peroxidation processes, which is expressed in minimal drop of MDA concentration.

[Evaluation of blood flow rate in the internal carotid system in various types of retinal vein occlusion]. / Ocena predkosci przeplywu krwi w ukladzie tetnicy szyjnej wewnetrznej w róznych postaciach zmian zakizepowych zyl siatkówki.

UNLABELLED: The aim of the study was to evaluate blood flow rate by means of Doppler pulsating ultrasonography focused in internal carotid artery, opthalmic artery and posterior ciliary arteries in patients with different types of retinal veins occlusion. The material included 8 patients with congestive venous retinopathy, 27 with ischaemic central retinal vein occlusion and 35 with central retinal vein branch occlusion. The flow measurements were performed using ultrasound 3-D trans Scan of EME company. RESULTS: Patients with ischaemic occlusion revealed statistically significant decrease of blood flow rate in opthalmic artery and posterior ciliary arteries on the ill eye side. Moreover, these patients had the worst course of the disease, including permanent sight defect, ischaemic complications in the funds of the eye and in fluorescein angiography. Flow measurements confirmed the role of arterial flow insufficiency in formation and clinical course of retinal vein occlusion and in development of complications.

[Evaluation of the general condition and selected biochemical blood parameters in various types of retinal vein occlusion]. / Ocena stanu ogólnego i wybranych parametrów biochemicznych krwi w róznych typach zmian zakrzepowych zyl siatkówki.

UNLABELLED: The aim of the study was to evaluate the coagulant and fibrinolytic system, lipid economy and neurological condition in patients with various types of retinal vein occlusion. The material was 70 patients: 8 with diagnosed congestive venous retinopathy, 27 with ischaemic central retinal vein occlusion and 35 with central retinal vein branch occlusion. Apart from the neurological evaluation, every patient underwent determination of: hematocrit, number of blood platelets, total plasma protein with its electrophoretic division, plasma fibrinogen level, kaolin-cephalin and prothrombin coefficient, and the level of triglycerides, total cholesterol with its fractions LDL and HDL. RESULTS: Considerable percentage of patients with arterial hypertension and suffering from partial or multi-symptomatic hemiparesis associated with complication in plasma lipid content indicates significant atheromatous changes in vascular wall which promote occlusion formation. The role of rheological factors in pathogenesis of these changes seems to be secondary.

[Clinical course and complications of different retinal occlusion types based on personal material]. / Przebieg kliniczny i powiklania róznych postaci zmian zakrzepowych w ukladzie zylnym siatkówki w materiale wlasnym.

UNLABELLED: The aim of the study was to analyse the clinical course and frequency of complications depending on type of retinal vein occlusion. The material included 70 patients (27 men, 43 women) aged 60.3 +/- 10.5 years. Follow-up period was 3 to 36 months from the occurrence of first clinical symptoms. Case history included occurrence of common diseases predisposing to occlusion formation, use of drugs and type of predromal symptoms. Full ophthalmologic examination was performed at the start and the end of follow-up. Visual field was measured with TOPCON statistic perimeter SPB 2020. Fluorescein angiography was done in 45 patients. RESULTS: 8 patients appeared to have congestive retinography, 27-ischaemic retinal vein occlusion and 35-central retinal vein branch occlusion. Prodromal symptoms were mainly short-term (few minutes) eye blindness. Both the evaluation of sight organ function and ophthalmoscopy indicated more severe course of ischaemic occlusion in comparison with congestive occlusion. Absence of retinal capillary perfusion was observed only in cases of ischaemic occlusion.

[Contemporary views on the etiopathogenesis of thrombotic changes in the retinal vein]. / Wspólczesne poglady na etiopatogeneze zmian zakrzepowych w ukladzie zylnym siatkówki.

The authors emphasize the complex and multifactorial mechanism by which retinal vein occlusion occurs. A special attention is paid to arterial insufficiency which impacts formation of clinical picture as well as the development of occlusion and the complications.

[Acquired color vision disturbances as a sensitive marker of chronic exposure to petroleum derivatives]. / Nabyte zaburzenia widzenia barw jako czuly wskaznik przewleklej ekspozycji na pochodne ropy naftowej.

The Farnsworth-Munsell 100 Hue test was used to examine 75 males aged 25-60 years before and after a break in exposure to petroleum derivatives and 30 males non-occupationally involved in the petrochemical industry. Acquired colour vision disturbances were found in 29% of those under study before and in 16% after a break in exposure and rest while in the control group they were diagnosed in 17% of subjects before and in 7% after rest. Remission of acquired dyschromatopsia of the blue and yellow axis was most commonly observed. This kind of disturbances accounted for 70% out of all disorders found in the basic group and they represented the only kind of disorders detected in the controls. An observed tendency towards remission of disturbances in the blue and yellow axis indicates a functional nature of the visual analyzer damage. Dyschromatopsia of the blue and yellow axis with concomitant disturbances in the red and green axis or without specified axis is more persistent and may indicate an organic damage of the route that transmits information about colours.