Light and electron microscopic morphology of accessory lacrimal glands.
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Cytoplasmic Granules↗
Biomedical subjects
M Spitznas
Publications and source records attributed to M Spitznas.
Influence of various pharmaceutical agents on tear flow as assessed by fluorophotometry.
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Bromhexine↗
Galactose- binding sites in the acinar cells of the human accessory lacrimal gland.
This investigation for the first time has collected evidence of a specific glycoconjugate contribution of the acinar cells from accessory lacrimal glands to human tears. Amongst group III lectin binding glycoconjugates, monosaccharides seem to be more prominent than disaccharides. alpha (and less obvious beta) Galactose sugar moieties appear to be specifically important. A need for further differentiating investigations is outlined.
Acetylgalactosamine↗
Increased lipid peroxide level and myeloperoxidase activity in the vitreous of patients suffering from proliferative vitreoretinopathy.
BACKGROUND: Retinal pigment epithelium cells and activated phagocytes are believed to be involved in the pathogenesis of proliferative vitreoretinopathy (PVR). Both cell types are capable of producing oxygen free radicals and other molecules with a high oxidative potential which can lead to a propagation of oxidative damage. It was the aim of this study to investigate whether products of oxidative reactions are detectable in the vitreous body of patients suffering from PVR. METHODS: In vitreous aspirates of patients vitrectomized because of PVR (n = 27), macular pucker (n = 9), or other reasons (controls, n = 31), the following parameters were determined: lipid peroxides (LPO), determined as malondialdehyde-like substances (MDA) and as thiobarbituric acid-reactive substances (TBARS), and myeloperoxidase activity (MPO). RESULTS: Compared with the controls, both LPO levels and MPO activities were significantly elevated in the vitreous of patients suffering from PVR. Vitreous of patients with macular pucker did not reveal any significant differences from controls in the parameters analyzed. CONCLUSION: Our results suggest that both oxygen free radicals and inflammation-related reactions participate in the process of PVR. Oxidative tissue damage is obviously not involved in the pathogenesis of macular pucker.
Free Radicals↗
Demonstration of nerve fibers in human accessory lacrimal glands.
To provide morphologic evidence for the innervation of accessory lacrimal glands, glands were biopsied and examined using standard transmission electron microscopic techniques. Non-myelinated nerve fibers were found in the connective tissue between the glandular epithelia where they made contact with glandular epithelial cells, myoepithelial cells, vascular endothelial cells, plasma cells and fibroblasts. The distances measured between axons and target cells ranged from 30 to 130 nm. Where nerve fibers approached cells sustaining a basement membrane, their basement membranes fused to form a discrete unit resembling so-called 'synapses à distance'. Cells with no basement membrane were situated in direct contact with the basement membrane of a nerve fiber. Single axons were identified between glandular epithelial cells and cells of intralobular ducts. Most of these axons contained many small clear vesicles and a few large, dense core vesicles, a finding considered typical of cholinergic parasympathetic nerve fibers. In addition, one of the axons identified contained small dense core vesicles typical of sympathetic nerve fibers. Human accessory lacrimal glands are therefore definitely innervated, with parasympathetic structures morphologically prevailing over sympathetic structures.
Axons↗
A light and electron microscopic study of the healing of pars plana incisions in the rhesus monkey.
Pars plana incisions were made in 11 rhesus monkey eyes. Six animals had injections of 0.1 ml of blood into the vitreous cavity with a 25-gauge needle and five animals had vitrectomy through a 4-mm incision with a multifunction vitrectomy probe. Six to 13 years later the scars in the pars plana were found to consist of fibrous tissue and blood vessels which extended from the episclera into the vitreous. The intravitreous scar was shaped by the incarceration of vitreous strands in the internal aspect of the wounds. There were quantitative, but no qualitative differences between the two types of incision. The ultrastructural features were those of mature scar tissue: fibroblasts, adult collagen, uveal melanocytes, macrophages, myelinated and non-myelinated nerves, and capillaries with non-fenestrated endothelium. There were associated proliferative ciliary epithelial changes, but no evidence of ciliary epithelial metaplasia.
Animals↗
Long-term results after removal of dislocated intraocular lenses from the retinal surface through a limbal approach.
BACKGROUND: The authors describe the use of a limbal approach for removing dislocated intraocular lenses (IOLs) from the retinal surface to minimize surgical trauma and optimize visual outcome. METHODS: Thirteen consecutive patients underwent removal of a dislocated posterior chamber IOL (PC IOL) from the retinal surface through a limbal approach. The surgical technique used in all patients included a limbal incision from the 3- to 9-o'clock positions; open-sky vitrectomy, grasping the IOL at the angle between loops and optics with an iris hook; and IOL removal through the corneoscleral opening. In all except one patient, who had high-degree myopia, an IOL was re-implanted during the same surgical procedure (free sulcus fixation of a PC IOL over remnants of the capsular bag, 7 patients; sulcus fixation of a PC IOL over remnants of the capsular bag combined with 1 transscleral suture, 3 patients; and implantation of an anterior chamber IOL, 2 patients). RESULTS: No retinal or corneal complications secondary to IOL removal and re-implantation through a limbal approach could be detected over an average follow-up period of 22.3 months (range, 17-27 months). Best-corrected visual acuity was 20/40 or better in seven patients, between 20/50 and 20/400 in three, and less than 20/400 in three. Visual outcome worse than 20/40 was related to pre-existing macular degeneration in five patients and retinitis pigmentosa in an additional one. CONCLUSIONS: The use of a limbal approach allows removal of an IOL from the retinal surface and secondary IOL implantation in the preferred site during the same surgical procedure. Because no special instrumentation is needed, this technique also is suitable for primary removal if dislocation occurs intraoperatively. The visual outcome and the long-term absence of complications recorded in our series indicate that a limbal approach may offer a reasonable alternative in managing IOLs luxated onto the retinal surface.
Adolescent↗
No cataract two years after pneumatic retinopexy.
PURPOSE: This study was conducted to examine possible adverse effects on lens transparency caused by pneumatic retinopexy using sulfur hexafluoride gas. METHODS: In a prospective study, both lenses of 33 patients undergoing pneumatic retinopexy in one eye were monitored up to 24 months postoperatively by slit-lamp examination and Scheimpflug photography. RESULTS: Pneumatic retinopexy does not cause significant lens opacifications up to 2 years after surgery. CONCLUSION: Temporary gas tamponade for pneumatic retinopexy is not associated with permanent changes in lens transparency.
Adult↗
Free radical scavenging and antioxidant activity of allopurinol and oxypurinol in experimental lens-induced uveitis.
PURPOSE: In addition to the inhibition of xanthine oxidase, allopurinol is known to act, dependent on the dose, as a free radical scavenger, an antioxidant, and a "scavenger" of hypochlorous acid. This activity was investigated using a model of lens-induced uveitis. METHODS: Lipid peroxides (LPO) were determined in aqueous humor and in retinal tissue. Reduced and oxidized glutathione (GSH and GSSG) of the aqueous humor and myeloperoxidase (MPO) activity in the iris-ciliary body complex were analyzed. Allopurinol and oxypurinol concentrations were determined by high-performance liquid chromatography in aqueous humor and retinal tissue of both control eyes and eyes with uveitis. These measurements were performed 6 hours after intravenous application of allopurinol. RESULTS: In lens-induced uveitis, LPO are significantly elevated, GSH is reduced, and GSSG and MPO are increased. A xanthine oxidase inhibition dose (< 10 mg/kg body weight) of allopurinol showed no effects on oxidative tissue damage in the model used in this study. Higher doses, however, were able to reduce the oxidative damage. Allopurinol (20 mg/kg body weight) had slight effects on GSH and GSSG. All parameters improved using a dose of 50 mg/kg body weight; a dose of 100 mg/kg body weight only showed additional improvement in GSH and GSSG. There was no further change in the other parameters. Allopurinol and oxypurinol concentrations in aqueous humor and retinal tissue showed a dose dependency reaching scavenger concentrations after application of 50 mg/kg body weight of allopurinol. CONCLUSIONS: These results suggest that the xanthine oxidase mechanism plays a minor role in the oxidative tissue damage due to lens-induced uveitis. Free radicals and oxidants are generated by activated leukocytes; therefore, the effect of higher doses of allopurinol is due to its free radical scavenging and antioxidative activity.
Allopurinol↗
[Chronic low grade endophthalmitis. A growing indication for explantation of intraocular lenses].
The aim of this study was to evaluate the effect of progress made in cataract surgery regarding the indications and results of intraocular lens (IOL) removal. For this purpose, the charts of all patients who had undergone IOL explantation at our institution between January 1990 and December 1992 were reviewed. Indications were divided into six groups: (a) chronic low-grade endophthalmitis; (b) pseudophakic bullous keratopathy; (c) luxation; (d) traumatic expulsion; (e) high-degree aniseikonia; (f) acute endophthalmitis. Visual acuities were grouped according to a good (1.0 to 0.5), acceptable (0.4 to 0.05) and poor (less than 0.05) outcome. Fifty-two IOL were removed from 52 eyes of 52 patients during the period considered in this study. Sixteen were anterior chamber, 5 were iris-fixated, and 31 were posterior chamber lenses. The removal rates were 30.8% for chronic, low-grade endophthalmitis (n = 16), 28.8% for bullous keratopathy (n = 15), 28.8% for luxation (n = 15), 5.8% for traumatic expulsion (n = 3), 3.8% for high-degree aniseikonia (n = 2), and 1.9% for acute endophthalmitis (n = 1). After explantation vision equal to or better than 20/400 was achieved by the vast majority of patients in all groups with the exception of those with bullous keratopathy. The progress made in cataract surgery over the last decade has greatly influenced the rate of complications leading to IOL removal. Continuous monitoring of explanted IOLs is mandatory to evaluate further changes in surgical technique and lens design.
Adolescent↗
Long-term results of sutureless phacoemulsification with implantation of a 7-mm polymethyl methacrylate intraocular lens.
In an attempt to minimize postoperative astigmatism while retaining the advantages of implanting intraocular lenses with large optics, sutureless phacoemulsification with implantation of a 7-mm polymethyl methacrylate intraocular lens was performed through a modified scleral tunnel in 100 consecutive patients. Visual and keratometric results, as well as complications, were recorded during a follow-up period of 12 months. Average uncorrected visual acuity improved from 20/153 before surgery to 20/66 as early as 1 week after surgery. Average best corrected visual acuity improved from 20/86 before surgery to 20/39 as early as 1 week after surgery. No significant changes in visual acuity were recorded thereafter. The absolute value of keratometric astigmatism was not increased significantly at any postoperative examination time. The induced cylinder shifted from 1.26 diopters x 74.40 degrees at 1 week to 1.22 D x 1.50 degrees at 1 month after surgery, without further relevant changes thereafter. Mean (+/- SD) endothelial cell loss was 7.2% +/- 6.1% at 1 month and 12.2% +/- 5.4% at 6 months after surgery. Corneal thickness was not increased significantly at any postoperative examination time. Implantation of intraocular lenses with large optics through a scleral tunnel allows quick visual rehabilitation as well as early stability of refraction.
Adult↗
Extracapsular cryoextraction and irrigation-aspiration procedure for removal of nuclear sclerotic lenses from vitrectomized eyes.
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Cataract Extraction↗
Increased lipid peroxide levels and myeloperoxidase activity in the vitreous of patients suffering from proliferative diabetic retinopathy.
Lipid peroxide (LPO) levels, as determined by high-performance liquid chromatography (HPLC) and by the thiobarbituric acid (TBA) method, and myeloperoxidase (MPO) activity in vitreous of patients vitrectomized because of proliferative diabetic retinopathy were compared with LPO levels and MPO activity in vitreous of patients with no vitreoretinal proliferation. Both LPO levels and MPO activity were significantly elevated in the vitreous of patients with fibrovascular vitreoretinal proliferations secondary to diabetes. The TBA method produced higher values for LPO levels than did the HPLC method. The correlation between the two methods was 0.94. Our results suggest that both oxygen-free radicals and inflammation-related reactions can participate in the pathogenesis of diabetic retinopathy.
Chromatography, High Pressure Liquid↗
Epithelial interface cysts after epikeratophakia.
BACKGROUND: Epithelial interface cysts have been occasionally observed after lamellar keratoplasty. The authors report the incidence, clinical significance, and management of this complication in epikeratophakia patients. METHODS: From August 1987 to January 1991, 108 consecutive patients undergoing epikeratophakia entered a prospective study aimed at evaluating both clinical results and changes in corneal physiologic parameters. After an average hospitalization of 6 days, all patients underwent complete ophthalmologic examinations at regular intervals after surgery. All postoperative complications, including the development of epithelial interface cysts, were recorded and photographed. RESULTS: Over a 3-year period, epithelial interface cysts were observed in 8 eyes, with an overall incidence of 7.4%. All cysts originated under the periphery of the epilens. In five patients, the cysts enlarged centripetally but eventually ceased to grow, causing no visual impairment. In two patients, after an initial increase in size the cysts slowly regressed and finally disappeared. In only one patient, a cyst migrated over the visual axis, thus necessitating surgical removal. The cyst did not recur during an observation time of 18 months after debridement, allowing full recovery of visual acuity. CONCLUSION: The incidence of epithelial interface cysts after epikeratophakia is relatively high. Because of their peripheral location and self-limited growth, the clinical significance of this complication is low. The possibility of spontaneous regression of the cysts supports a conservative approach, as long as the visual axis is not affected. Surgical removal is possible without compromising the epi-lens and is compatible with an excellent visual outcome.
Adult↗
Effect of topical 0.5% timolol on tear flow in patients with primary open-angle glaucoma as assessed by fluorophotometry.
The question as to whether or not topical medication with beta blockers causes a decrease in tear production remains unanswered. Earlier studies using filter-paper strip tests have yielded contradictory results. In the present study, computerized objective fluorophotometry was used to assess the effect of topical medication with 0.5% timolol (b.i.d.; OU) on tear volume and tear production in 24 consecutive patients with bilateral primary open-angle glaucoma. Tear-film fluorophotometry was performed before treatment as well as at 7 days, 14 days, and 4-7 months after the onset of treatment. The results showed that by 7 days after the initiation of timolol treatment, both tear volume (-29%, P < 0.01) and tear secretion (-36%, P < 0.01) had decreased significantly. However, at both 14 days and 4-7 months after the onset of treatment, none of the values differed significantly from those obtained before treatment. Thus, topical antiglaucomatous treatment with 0.5% timolol eye drops leads to a transient decrease in tear production. This effect, however, lasts no longer than 14 days after the beginning of treatment.
Administration, Topical↗
The architecture of human accessory lacrimal glands.
Human accessory lacrimal glands were examined both light and electron microscopically and their gross architecture was reconstructed from serial sections. Every accessory lacrimal gland nodule is an individual organ with its own connective tissue coat and excretory duct. Within the gland proper, the excretory duct ramifies to form intralobular ducts, which are connected to the secretory glandular epithelia. The secretory epithelia are composed of elongated tubules terminating in short end pieces with lumina of variable width. True acini are absent. Thus, the accessory lacrimal glands are tubular glands. The cells of tubules and end pieces contain large secretory granules suggestive of a regulated mechanism of secretion. The content of organelles and the amount of secretory material present in neighboring cells can show pronounced differences. Both end pieces and tubules and, to a lesser extent, the intralobular ducts are surrounded by myoepithelial cells. The interstitial connective tissue contains blood vessels, free cells, and fibroblasts. Axons of nonmyelinated nerve fibers are in close spatial contact to vascular endothelial cells, connective tissue cells, free cells, and glandular epithelial cells. A few axons with parasympathetic characteristics and, less frequently, with sympathetic characteristics were identified between the epithelial cells of both secretory epithelium and intralobular ducts.
Blepharoptosis↗
[Phacoemulsification without suture. Results of implantation of a large optic PMMA lens].
Sutureless phacoemulsification with implantation of a 7-mm PMMA intraocular lens was performed through a modified scleral tunnel in 100 consecutive patients. This was done to minimize postoperative astigmatism while retaining the advantages of implanting intraocular lenses with large optics. Visual and keratometric results and complications are reported after completion of a follow-up period of 6 months for the first 30 patients. Average uncorrected visual acuity improved from 0.13 preoperatively to 0.30 as early as 1 week postoperatively. Average best-corrected visual acuity improved from 0.23 before surgery to 0.51 as early as 1 week after surgery. No significant changes in visual acuity were recorded thereafter. The absolute value of keratometric astigmatism was not increased significantly at any postoperative examination time. The induced cylinder (Jaffe and Clayman) shifted from -1.27 D x 166 degrees at 1 week to 1.18 D x 91 degrees at 1 month postoperatively without further relevant changes thereafter. Endothelial cell loss did not differ from that reported by other authors after conventional cataract surgery. Corneal thickness was not increased significantly at any postoperative examination time. Implantation of intraocular lenses with large optics through a scleral tunnel allows quick visual rehabilitation as well as early stability of refraction.
Adult↗
Corneal epithelial permeability of dry eyes before and after treatment with artificial tears.
PURPOSE: The question of whether artificial tears can lead to objective improvement of ocular surface disease in dry eyes is still unanswered. The aim of the current study is to assess the influence of artificial tears on corneal epithelial permeability of dry eyes. Furthermore, the effect of benzalkonium chloride, used as a preservative of artificial tears, on corneal epithelial permeability is investigated. METHODS: The corneal epithelial permeability of 40 dry eye patients (80 eyes) was measured by computerized objective fluorophotometry before and 6 weeks after treatment with artificial tears containing either polyvinyl pyrrolidone 2% without preservative (20 patients) or polyvinyl pyrrolidone 2% preserved with benzalkonium chloride 0.005% (20 patients). RESULTS: Before treatment, the epithelial permeability of the dry eye patients was found to be 2.7 times that of a control group. After treatment, the epithelial permeability of patients treated with unpreserved polyvinyl pyrrolidone 2% had decreased significantly (-37%; P less than 0.001), whereas patients who had been treated with polyvinyl pyrrolidone 2% preserved with benzalkonium chloride 0.005% showed an increase in epithelial permeability (+21%; P = 0.05%). CONCLUSION: These data suggest that, in dry eyes, treatment with unpreserved artificial tears may lead to an objective improvement in corneal surface disease. However, this effect may be counteracted by preservation of tear substitutes with benzalkonium chloride.
Benzalkonium Compounds↗