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1.
In vivo confocal microscopy in the normal corneas of cats, dogs and birds   总被引：1，自引：1，他引：0  
OBJECTIVE: To evaluate the applicability of in vivo confocal microscopy (IVCM) in veterinary ophthalmology and analyze the morphology of living, healthy cornea. ANIMALS EXAMINED: Thirty-seven dogs, 34 cats and five birds. PROCEDURE: Various corneal sublayers were visualized in the central region using an in vivo confocal corneal microscope (HRTII/RCM). RESULTS: An investigation method was developed and adapted for use on animals with varying skull forms and eye positions. Real-time images of the epithelial cells, the corneal stroma and the endothelial layer were obtained. The corneal stromal nerve trunks and the subepithelial and basal epithelial nerve plexus were visualized. In dogs, full corneal thickness (FCT) was 585 +/- 79 microm (mean +/- SD) and endothelial cell density (ECD) 3175 +/- 776 cells/mm(2) (mean +/- SD). In cats, FCT was 592 +/- 80 microm and ECD 2846 +/- 403 cells/mm(2). There were no significant differences between canine and feline FCT and ECD and no morphologic differences could be seen between dogs and cats. The bird images revealed a number of structural differences. CONCLUSION: Noninvasive IVCM allows accurate detection of corneal sublayers, corneal pachymetry, endothelial cell density and corneal innervation in various animal species. For clinical usage, patients must be under general anesthesia. The confocal images provided anatomic reference images of various healthy corneal structures in dogs, cats and birds.  相似文献   

2.
Endothelial cell function is essential to maintain corneal transparency, but unfortunately the regenerative capacity of the endothelium is limited. There are only a few reports describing the effect of age on morphologic appearance of corneal endothelial cells of dogs. Studies of normal corneal endothelial cells in humans and dogs have shown a decrease in endothelial cell density (ECD) and an increase in pleomorphism and polymegethism with advancing age. The purpose of this study was to investigate the effect of age on ECD and endothelial cell morphology in dogs. A total of 30 dogs were divided into three groups (10 dogs/group) based on age: group 1 (2-12 months old), group 2 (24-72 months old), and group 3 (84 months or older). Corneas were processed for light and scanning electron microscopy. Results showed only difference in cell density between group 1 and groups 2 and 3, showing an initial decrease in cell density as the animal matured. Whereas there was significantly greater variation in cell size within the dogs in group 3 than there was within the other two groups, suggesting that there was increased polymegethism and pleomorphism with advancing age.  相似文献   

3.
The corneal endothelium is essential for the maintenance of the corneal transparency. The aim of this study was to examine the morphology of the endothelial surface and perform morphometric analysis of the normal corneal endothelial cells of the Magellanic penguin (Spheniscus magellanicus) using scanning electron microscopy. The present work demonstrates that the corneal endothelium of the Magellanic penguin is similar to those described in other vertebrates.  相似文献   

4.
The purpose of this study was to investigate the effect of age on endothelial morphology and morphometry in cats. The corneal endothelium was studied using a contact specular microscope. A total of 18 cats (Felis catus Linnaeus, 1758) were evaluated in this study. The subjects were divided into three groups of six cats each in function of age: G1 (1 to 3 months old), G2 (5 to 12 months old), and G3 (24 to 40 months old). The examination presented data as endothelial cell density (ECD), average cell area, corneal thickness, polymegathism, and pleomorphism. Results revealed ECD decrease in corneas of normal cats with age, as well as a corresponding increase in endothelial cell area and pleomorphism. The present work suggests that the endothelial parameters evaluated change with advancing age.  相似文献   

5.
Objective  To describe morphologic features, pachymetry and endothelial cell density of the normal equine cornea and limbus by in vivo confocal microscopy.
Animals studied  Ten horses without ocular disease.
Procedure  The central and peripheral corneas were examined with a modified Heidelberg Retina Tomograph II and Rostock Cornea Module using a combination of automated and manual image acquisition modes. Thickness measurements of various corneal layers were performed and endothelial cell density determined.
Results  Images of the constituent cellular and noncellular elements of the corneal epithelium, stroma, endothelium, and limbus were acquired in all horses. Corneal stromal nerves, the subepithelial nerve plexus, and the sub-basal nerve plexus were visualized. Cells with an appearance characteristic of Langerhans cells and corneal stromal dendritic cells were consistently detected in the corneal basal epithelium and anterior stroma, respectively. Median central total corneal thickness was 835 μm (range 725–920 μm) and median central corneal epithelial thickness was 131 μm (range 115–141 μm). Median central endothelial cell density was 3002 cells per mm2 (range 2473–3581 cells per mm2).
Conclusions  In vivo corneal confocal microscopy provides a noninvasive method of assessing normal equine corneal structure at the cellular level and is a precise technique for corneal sublayer pachymetry and cell density measurements. A resident population of presumed Langerhans cells and corneal stromal dendritic cells was detected in the normal equine cornea. The described techniques can be applied to diagnostic evaluation of corneal alternations associated with disease and have broad clinical and research applications in the horse.  相似文献   

6.
Objective To investigate the potential damage to the canine corneal endothelium following transcorneal iridal laser photocoagulation using a semiconductor diode laser. Animals studied Sixteen young mongrel dogs. Procedures Baseline corneal endothelial cell counts and corneal thickness were measured in the central and temporal quadrants using a noncontact specular microscope under general anesthesia. Transcorneal iridal photocoagulation was applied using a semiconductor diode laser in a continuous mode with the use of an operating microscope. Fifteen dogs were treated, and the sixteenth dog served as a control. Fifteen different treatment combinations were randomly assigned to the 30 eyes; the fellow eye was treated differently. Three treatment factors were investigated: (1) laser energy intensity, (2) target tissue to endothelial distance, and (3) laser application duration. After 3 weeks the dogs were euthanized, specular microscopy was repeated, and the cornea was examined by scanning electron microscopy. Results Dyscoria and focal iris darkening were noted in all eyes immediately following laser treatment. Focal corneal edema (n = 2) and an incipient anterior capsular cataract (n = 1) were also noted. Baseline mean corneal endothelial cell densities were 2530 cells/mm2 centrally and 2607 cells/mm2 temporally. Postlaser corneal endothelial cell densities were 2499 cells/mm2 centrally and 2523 cells/mm2 temporally. Mean prelaser corneal thickness measurements were 0.555 mm centrally and 0.549 mm temporally. Postlaser corneal thickness measurements were 0.580 mm centrally and 0.554 mm temporally. Statistical analyzes revealed no significant changes in endothelial cell densities (P > 0.05) or corneal thickness (P > 0.05) induced by any treatment combination. Aside from tissue handling and processing artifacts, scanning electron microscopy revealed no endothelial cell damage. Conclusions Our study demonstrated by specular and scanning electron microscopy that diode laser iridal photocoagulation had no significant effect on the canine corneal endothelium within the parameters described. However, one must take into consideration the young age of the dogs and the potential for corneal endothelial cell regeneration in young dogs, and the relatively short period of postoperative study.  相似文献   

7.
OBJECTIVE: To determine density of corneal endothelial cells and corneal thickness in eyes of euthanatized horses. SAMPLE POPULATION: 52 normal eyes from 26 horses. PROCEDURE: Eyes were enucleated after horses were euthanatized. Eyes were examined to determine that they did not have visible ocular defects. Noncontact specular microscopy was used to determine density of corneal endothelial cells. Corneal thickness was measured, using ultrasonic pachymetry or specular microscopy. RESULTS: Mean density of corneal endothelial cells was 3,155 cells/mm2. Cell density decreased with age, but sex did not affect cell density. Values did not differ significantly between right and left eyes from the same horse. Cell density of the ventral quadrant was significantly less than cell density of the medial and temporal quadrants. Mean corneal thickness was 893 microm. Sex or age did not affect corneal thickness. Dorsal and ventral quadrants were significantly thicker than the medial and temporal quadrants and central portion of the cornea. We did not detect a correlation between corneal thickness and density of endothelial cells in normal eyes of horses. CONCLUSIONS AND CLINICAL RELEVANCE: Density of corneal endothelial cells decreases with age, but corneal thickness is not affected by age or sex in normal eyes of horses. The technique described here may be useful for determining density of endothelial cells in the cornea of enucleated eyes. This is clinically relevant for analyzing corneal donor tissue prior to harvest and use for corneal transplantation.  相似文献   

8.
Wound repair in horse limbs is often complicated by excessive fibroplasia and scarring. Occlusion of the microvessels populating the granulation tissue appears to be involved in the excessive accumulation of extracellular matrix during the repair of limb wounds. This study aimed to determine whether endothelial cell hypertrophy or hyperplasia, or both, contribute to microvascular occlusion and whether the pericyte is involved in this anomaly. We created 5 wounds, each 2.5 x 2.5 cm, on both forelimbs and on the body of 6 horses. One limb was bandaged to stimulate excessive wound fibroplasia. Weekly biopsy specimens were evaluated by transmission electron microscopy to measure microvessel luminal diameters and the surface area of endothelial cells and to count endothelial cells and pericytes. Microvessels were occluded significantly more often in limb wounds than in body wounds. The surface area of endothelial cells lining occluded microvessels (mean +/- standard error, 28.4013 +/- 1.5154 microm2) was significantly greater (P = 0.05) than that of cells lining patent microvessels (26.2220 +/- 1.5268 microm2). Conversely, neither the number of endothelial cells nor the number of pericytes differed between patent and occluded microvessels or between limb and body wounds. Furthermore, the wound location and the status of the microvessels (patent or occluded) did not alter the ratio of endothelial cells to pericytes. These data suggest that endothelial cell hypertrophy might play a role in the microvascular occlusion present in granulation tissue of limb wounds in horses, but the contribution of the pericyte remains obscure.  相似文献   

9.
OBJECTIVE: To determine density of corneal endothelial cells, corneal thickness, and corneal diameters in normal eyes of llamas and alpacas. ANIMALS: 36 llamas and 20 alpacas. PROCEDURE: Both eyes were examined in each camelid. Noncontact specular microscopy was used to determine density of corneal endothelial cells. Corneal thickness was measured, using ultrasonographic pachymetry. Vertical and horizontal corneal diameters were measured, using Jameson calipers. RESULTS: Values did not differ significantly between the right and left eyes from the same camelid. There was no significant effect of sex on density of corneal endothelial cells or corneal thickness in either species. Mean density of endothelial cells was 2,669 cells/mm2 in llamas and 2,275 cells/mm2 in alpacas. Density of endothelial cells decreased with age in llamas. Polymegathism was observed frequently in both species. Mean corneal thickness was 608 microm for llamas and 595 microm for alpacas. Corneal thickness and density of endothelial cells were negatively correlated in llamas. Older (> 36 months old) llamas had significantly larger horizontal and vertical corneal diameters than younger llamas, and older alpacas had a significantly larger vertical corneal diameter than younger alpacas. CONCLUSIONS AND CLINICAL RELEVANCE: Density of corneal endothelial cells is only slightly lower in camelids than other domestic species. Density of endothelial cells decreases with age in llamas. Age or sex does not significantly affect corneal thickness in normal eyes of llamas and alpacas. Specular microscopy is useful for determining density of corneal endothelial cells in normal eyes of camelids.  相似文献   

10.
Erythrocyte volume distribution in rainbow trout   总被引：1，自引：0，他引：1  
Reference mean corpuscular volume and volume heterogeneity values for erythrocytes of 23 rainbow trout were measured, using an electronic particle counter, and were analyzed, using a particle-size analyzer and microcomputer. The mean (+/- SD) erythrocyte count was 1.5 X 10(6) +/- 0.16 X 10(6) cells/microliter, the mean corpuscular volume was 346 +/- 25 fl, and the mean coefficient of variation of erythrocyte volumes was 29 +/- 2.3%. All erythrogram curves were skewed to the right, representing a mean of 15.6 +/- 3.5% of the total cells counted.  相似文献   

11.
Tooth surface and interradicular area (furcation) measurements were taken of 20 first mandibular molar teeth obtained randomly from canine cadavers. The lingual furcation entrance had a mean width of 1.2 +/- 0.3 mm. The buccal furcation entrance had a mean width of 1.3 +/- 0.4 mm. There was no significant difference between mean furcation entrance measurements. The horizontal attachment area between the cementoenamel junction and the coronal roof of the lingual furcation was 1.1 +/- 0.4 mm. The horizontal attachment area between the cementoenamel junction and the coronal roof of the buccal furcation (0.5 +/- 0.3 mm) was significantly different from the lingual horizontal attachment area. Distal root length and mesial root length were 16.0 +/- 1.5 mm and 16.1 +/- 1.6 mm, respectively. The mean coefficient of variation for variables measured was 14.0%. Tooth size did not have a significant effect on furcation entrance measurement. All teeth had a concavity coronal to the furcation area, which extended apically for a mean distance of 65.6% of the distal root length and 83.8% of the mesial root length. Furcation anatomy of the first mandibular molar is complex and may be a contributing factor in periodontal disease involving the interradicular area.  相似文献   

12.
As part of a clinical workup of dental problems in a large crocodilian collection, mandibular nerve blocks were performed in the animals. A nerve locator was used to facilitate placement of the nerve blocks in American alligators (Alligator mississippiensis), Yacare caiman (Caiman yacare), and a dwarf crocodile (Osteolaemus tetraspis). Provision of analgesia is a frequently underused aspect of patient care in reptiles. Use of a nerve stimulator provides an objective measurement of nerve conduction blockade and may be useful in exotic species in which anatomic landmarks for nerve block placement are not well established.  相似文献   

13.
Contact in vivo wide-field specular microscopy was performed on right eyes of 20 healthy dogs after sodium hyaluronate (1%, n = 5), sodium chondroitin sulfate (4%) and sodium hyaluronate (3%, n = 5), hydroxypropyl methylcellulose (2%, n = 5), or balanced salt solution (control, n = 5) was injected into the anterior chamber. Using computerized morphometric analysis and pachymetry, changes in endothelial cell density, cell morphologic features, and corneal thickness from baseline values were evaluated at postinjection hour (PIH) 72 and PIH 168. Changes were not seen in endothelial cell density or cell morphologic features in any treated eye. The mean corneal thickness of all treated eyes at PIH 72 increased 6%, significantly greater than that of the nontreated eyes (P = 0.03). Mean corneal thickness of treated and nontreated eyes was similar at baseline and PIH 168 in all treatment groups.  相似文献   

14.
The lamina cribrosa surface of the pig was examined using trypsin digestion, scanning electron microscopy, and computerized image analysis. Six normal eyes from healthy pigs were studied. The total intralaminar scan area, total number of laminar pores, median individual laminar pore areas, median individual pore form factors, and mean pore density were determined for the dorsal, ventral, nasal and temporal hemicircles, the dorsal-nasal, dorsal-temporal, ventral-nasal, and ventral-temporal quadrants, and their central and peripheral subdivisions. The mean (+/- SD) total intralaminar scan area was 8.29 +/- 1.54 mm2. The mean (+/- SD) total laminar pore count was 517 +/- 73 pores. The mean pore count was significantly larger in the ventral than the dorsal hemicircle (292 +/- 39 vs. 225 +/- 38 pores, respectively; P = 0.001), and significantly greater in the periphery compared to the center (388 +/- 58 vs. 129 +/- 27 pores, respectively; P = 0.0001). The overall mean (+/- SD) pore density was 67 +/- 7 pores mm-2. Mean pore density was significantly greater in the ventral than the dorsal hemicircle (70 +/- 8 vs. 64 +/- 6 pores mm-2, respectively; P = 0.019), and significantly greater in the center compared to the periphery (75 +/- 9 vs. 60 +/- 8 pores mm-2, respectively; P = 0.020). The mean (+/- SD) median individual pore area was 3752 +/- 572 &mgr;m2. The mean (+/- SD) median pore form factor was 0.680 +/- 0.035. No significant regional differences were found in mean median pore form factor or mean median individual pore areas. The intralaminar optic nerve of pigs is 55.1% non-neural connective and vascular tissue. A pigmented ventral fascial groove in the scleral lamina cribrosa appears unique to the porcine lamina cribrosa, and may be a vestige of the embryonic optic fissure.  相似文献   

15.
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16.
Tooth surface and interradicular area (furcation) measurements were determined for 20 fourth maxillary premolar teeth obtained randomly from canine cadavers. The palatal furcation entrance had a mean width of 1.2 +/- 0.1 mm. The coronal roof of the palatal furcation was located at the cementoenamal junction (CEJ). The buccal furcation entrance had a mean width of 0.9 +/- 0.2 mm. The horizontal attachment area between the CEJ and the coronal roof of the buccal furcation was 1.3 +/- 0.3 mm. The mesial furcation entrance had a mean width of 0.4 +/- 0.1 mm. The horizontal attachment area between the CEJ and the coronal roof of the mesial furcation entrance was 1.7 +/- 0.3 mm. The mean coefficient of variation for variables measured was 10.3%. Tooth size did not have a significant effect on furcation entrance measurement. All teeth had a fluted area between the CEJ and mesial furcation, a concavity coronal to the furcation area, a distal concavity of the mesial root trunk between the mesiopalatal and mesiobuccal roots, and a mesial furcation concavity of the distal root extending apically for a mean distance of 60% of the distal root length. The complexity of furcation entrance anatomy may be a factor in the manifestation of periodontal disease involving the furcation of the fourth maxillary premolar in dogs.  相似文献   

17.
Tooth root and root trunk surface area measurements were taken from 20 first mandibular molar (M1) teeth obtained randomly from canine cadaver specimens. The mean root surface area for all teeth was 497.1 +/- 116.2 mm2. The cumulative surface areas of the mesial (MR) and distal (DR) roots were 251.4 +/- 70.2 mm2 and 211.7 +/- 51.9 mm2, respectively. The root trunk surface area was 34.0 +/- 21.4 mm2. Surface area measurements for individual roots and the root trunk were significantly different. Cumulative individual root surface area (MR + DR) was 93.2% of total root surface area. The MR surface area contributed most to total root surface area (50.6%) and cumulative individual root surface area (54.3%). The mean distance from the beginning of the root trunk to the furcation was 2.1 mm. On the basis of the linear variation of the percentage of root surface area of the M1, 44.6% of the total root surface area was 3 to 7 mm apical to the most coronal aspect of the cementoenamel junction. The MR was heart-shaped, compared with the more cylindrical shape of the DR.  相似文献   

18.
Accumulation of equine eosinophils at sites of parasite infestation or allergic inflammation depends upon their adherence to vascular endothelial cells and subsequent migration through the endothelium and extracellular matrix. This study has examined whether cytokines, which cause endothelial cell-dependent eosinophil adherence in other species, and histamine and substance P, which increase adherence of equine eosinophils to protein coated plastic, induce equine eosinophil adherence to cultured equine digital vein endothelial cell (EDVEC) monolayers. The EDVEC monolayers were stimulated with recombinant human (rh) interleukin (IL)-1beta, rhTNFalpha, substance P or histamine for different times and with a range of concentrations of mediators and the adherence of blood eosinophils from normal horses examined. All four mediators caused time- and concentration-dependent increases in adherence. However, neither the response to substance P, nor that to histamine, reached a maximum at the highest concentration tested (10-3 M: 10.6 +/- 2.6% and 4.5 +/- 0.6% adherent cells vs. background adherence of 1.9 +/- 0.4% and 1.1 +/- 0.2%; values for substance P and histamine, respectively, expressed as a percentage of total cells added initially; n=4). These data suggest that, as in other species, cytokines induce endothelial cell-dependent eosinophil adherence and mediators released during allergic inflammation may play a role in eosinophil recruitment by this mechanism.  相似文献   

19.
The aim of this study was to measure the direct release of nitric oxide (NO) from the porcine mitral valve using a NO microelectrode. Furthermore, the expression and localization of endothelial nitric oxide synthase (eNOS) in the mitral valve was studied using immunohistochemistry, Western blotting and RT-PCR. Results show that bradykinin increases NO release from mitral valves (DeltaBradykinin: 33.71 +/- 10.41 nm NO, P < 0.001, n = 10), whereas N-nitro-l-arginine methyl esther (l-NAME) decreases NO release when compared with basal level (Deltal-NAME: 82.69 +/- 15.66 nm NO, P < 0.005, n = 4). Both protein and mRNA expression of eNOS in mitral valves and in isolated valvular endothelial cells suggest that the NO release is mainly associated with the mitral valve endothelium. It is concluded that direct NO release from porcine mitral valves coincides with eNOS expression. This study documents useful techniques for investigations into the role of local NO release in mitral valve diseases.  相似文献   

20.
The replacement of the normal endothelial cell morphology with formation of a fibrocellular posterior collagenous layer by the corneal endothelium was demonstrated in an eight-year-old male German shepherd dog with bilateral progressive corneal oedema. Descemet's membrane was multilaminar and thickened. The ultrastructural findings in this dog are similar but not identical to histological changes present in several human corneal diseases.  相似文献   

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