Biomedical subjects

M Spitznas

Publications and source records attributed to M Spitznas.

At least 73 records · Page 4Linked to original sources

PubMed1992

Tear secretion in dry eyes as assessed by objective fluorophotometry.

To date, little information has been available about the actual amount of tear secretion in dry eyes. In the present study tear secretion was studied in 20 consecutive dry eye patients [40 eyes; Schirmer test after topical anesthesia < 5.5 mm/5 min; at least moderate squamous metaplasia of the conjunctival epithelium; bengal rose staining (Bijsterveld score > 4); severe dry eye complaints]. Tear secretion was evaluated by automated, computerized objective fluorophotometry and compared with that in an age-matched healthy control group. Tear secretion of the dry eyes examined was found to have decreased drastically (0.2 +/- 0.2 microliters/min) compared with that in healthy control eyes (1.2 +/- 0.5 microliters/min; P < 0.001). None of the dry eyes had a tear secretion of > 0.4 microliters/min.

Anesthesia, Local↗

PubMed1991

Leukoplakia of the cornea presenting as fingerprint epithelial lines: a case report.

Opacities in association with fingerprint patterns of the epithelium were seen in the upper half of the right cornea of a 52-year-old patient complaining of decreased vision. Removal of the corneal epithelium from the involved area resulted in visual improvement and normalization of corneal appearance. Histological examination of the removed epithelium failed to reveal the typical intraepithelial formation of basement membrane invaginations even in the areas corresponding to the fingerprint patterns. Moderate to severe degree of atypia were seen in the epithelial cells. No abnormalities were observed in 3 conjunctival specimens excised at the time of epithelial removal. The diagnosis of corneal dysplasia (leukoplakia) was made. Our report is the first description of epithelial fingerprint patterns of the cornea associated with leukoplakia.

Basement Membrane↗

PubMed1991

A multiport illumination system for panoramic bi-manual vitreous surgery.

A multiport illumination system (MIS) suitable for use during microsurgery of the vitreous body is presented. The MIS consists of several thin, illuminated pilot tubes, which are secured in the pars plana region and emit bright light at a wide angle. Through their lumen interchangeable 20 gauge instruments for active bi-manual vitreous surgery and an infusion pipe can be introduced. The system illuminates the entire field of wide-angle observation devices without the need for an additional hand-held light source.

Animals↗

PubMed1991

Endothelial barrier function after phacoemulsification: a comparison between diabetic and non-diabetic patients.

In all, 21 diabetic and 23 non-diabetic patients underwent endothelial fluorophotometry before and at 4 days, 3 weeks and 6 weeks after phacoemulsification with posterior chamber intraocular lens (IOL: PMMA) implantation. After topical fluorescein instillation, fluorophotometry was performed using an automated computerized fluorophotometer. The aim of this study was to assess early postoperative endothelial damage quantitatively and to detect possible differences between diabetic and non-diabetic patients in that regard. Preoperatively, the endothelial permeability of diabetic patients did not differ from that of non-diabetic individuals (P = 0.5). At 4 days after phacoemulsification with posterior chamber IOL implantation, endothelial permeability was significantly increased in both groups (P less than 0.001), but significantly more so in diabetic patients (P less than 0.001). The endothelial barrier function had fully recovered 3 weeks after surgery in non-diabetic subjects and 6 weeks after surgery in diabetic patients as well.

Aged↗

PubMed1991

Effect of topically applied oxymetazoline on tear volume and tear flow in humans.

Vasoconstrictive, alpha-sympathicomimetic eye drops are ophthalmic drugs that are extensively used. However, patients often complain of typical dry eye symptoms, especially after long-lasting application of such eye drops. In the present study, the effect of sympathicomimetic eye drops (0.026% oxymetazoline) on the tear volume and tear flow of 38 healthy individuals was determined quantitatively by means of objective fluorophotometry. Both tear volume and tear flow were found to be significantly (P less than 0.001) decreased up to 6 h after instillation, reaching a minimum 90 min after application (tear volume: -63%; tear flow: -71%). Thus, alpha-sympathicomimetic eye drops containing 0.026% oxymetazoline lead to a marked and protracted decrease in tear volume and tear flow. After frequent or long-lasting application, this fact may be responsible for severe dry eye conditions.

Administration, Topical↗

PubMed1991

Effects of artificial tears on corneal epithelial permeability in dry eyes.

The aim of this study was to detect possible changes in the permeability of the corneal epithelium in dry eye patients treated with artificial tears. For this reason, corneal epithelial permeability was measured in 68 consecutive dry eye patients before and after 8 weeks of treatment with artificial tears by means of objective fluorophotometry (polyvinyl alcohol 1.4% + chlorobutanol 0.5%, 25 subjects; polyvinyl pyrrolidone 2% + benzalkonium chloride 0.005%, 25 subjects; polyvinyl pyrrolidone 2% without preservative, 18 subjects). Before treatment, the stromal fluorescein uptake of dry eyes was three times higher than that of healthy control eyes. Eight weeks after the beginning of treatment the corneal epithelial permeability of patients treated with polyvinyl alcohol 1.4% + chlorobutanol 0.5%, as well as of those treated with polyvinyl pyrrolidone 2% without preservative, was reduced significantly (-44.9% and -43.4%, respectively; P less than 0.001). However, patients who had been treated with polyvinyl pyrrolidone 2% + benzalkonium chloride 0.005% showed no significant change in corneal epithelial permeability after treatment (-7.9%; P = 0.3).

Cornea↗

PubMed1991

Idiopathic posterior subretinal neovascularization (IPSN) is related to myopia.

In 153 eyes with idiopathic posterior subretinal neovascularization (IPSN) and myopia of no greater than -6 dpt, the relative risk of this disorder was determined with regard to refraction. It was shown that the probability of developing this condition is directly proportional to the degree of myopia. By using data obtained from the literature for calculating the relative risk regarding refraction, it was demonstrated that the same is true for subretinal neovascularization in degenerative myopia greater than -7.5 dpt (Fuchs' spot). The relative risk for developing one of both disorders increases exponentially with increasing myopia.

Adolescent↗

PubMed1991

Effect of eledoisin on tear volume and tear flow in humans as assessed by fluorophotometry.

Topical application of the endekapeptide eledoisin has been reported to increase tear secretion in patients with dry eye. However, to date the efficacy of eledoisin has been proved only by methods that are not easily reproduced and have an enormous intraindividual scatter range (Schirmer test, basic secretion test). In the present study the effect of topically applied eledoisin on tear volume and tear flow was determined quantitatively by means of objective fluorophotometry in 40 subjects, 20 of whom suffered from severe dry eyes. Both tear volume and tear flow were found to be significantly increased up to 2 h after instillation, reaching a maximum 1 h after application (tear volume: +87% and +35% for dry eyes and healthy controls, respectively; tear flow: +250% and +27% for dry eyes and healthy controls, respectively).

Administration, Topical↗

PubMed1991

Is chronic intraocular inflammation after lens implantation of bacterial origin?

In an effort to better understand the cause of chronic intraocular inflammation after intraocular lens (IOL) implantation, both scanning and transmission electron microscopy were used to compare 1 anterior chamber, 1 iris-fixated, and 3 posterior chamber IOLs removed for this condition between 2 and 16 months after implantation with 8 IOLs explanted for other reasons (decentration in 4 cases, bullous keratopathy in 4 cases). Colonization with non-slime-producing, as well as slime-producing bacteria (1 case) in the presence of a thin membranous structure of cellular origin (multinucleated giant cells and macrophage-like cells) was demonstrated on all of the 5 IOLs explanted from inflamed eyes. Neither bacteria nor membranous structures could be identified on the IOLs removed because of dislocation or from eyes with bullous keratopathy. These observations indicate that bacterial colonization and the consequent host response may be characteristic features of many otherwise unexplained cases of intraocular inflammation after IOL implantation.

Aged↗

PubMed1991

Mycotic infection of the capsular bag in postoperative endophthalmitis.

A case of mycotic infection after uncomplicated extracapsular cataract extraction with implantation of a posterior chamber modified C-loop intraocular lens (IOL) is reported. Severe postoperative intraocular inflammation, diagnosed by aqueous cultures as secondary to Staphylococcus aureus endophthalmitis, did not respond to antibiotic therapy. Despite IOL and capsular bag removal and further antibiotic treatment, the inflammation persisted and phthisis followed. Retrospective electron microscopic examination of the explanted material demonstrated the presence of abundant fungal elements in the capsular bag and spores on the IOL surface. Vitreous taps performed at the time of explantation were negative for bacteria and fungi, confirming the localized nature of the mycotic infection. To our knowledge this report represents the first observation of a mycotic infection confined to the capsular bag after cataract surgery with implantation of a posterior chamber IOL.

Aged↗

PubMed1991

[Perioperative risk of infection in cataract surgery].

The presence of bacteria during cataract surgery was studied on 71 consecutive patients. Lid and conjunctival smears were cultured 24 hours preoperatively. Additional conjunctival smears were harvested in the operating room before and after conjunctival disinfection by oxycyanate. Moreover, the whole irrigation fluid was collected under sterile condition and examined microbiologically. 24 hours preoperatively 61 of 71 patients had positive cultures of their lids and/or conjunctivae. 8 of them showed growth of pathogenous bacteria (7 staphylococcus aureus, 1 proteus mirabilis). In the operating room before oxycyanate disinfection 5 patients were positive for staphylococcus aureus and 13 for coagulase negative staphylococci (none for proteus species). After oxycyanate disinfection 4 residual conjunctival smears showed bacterial growth when cultured (3 coagulase negative staphylococci, 1 proteus mirabilis). 22 of 71 collected irrigation fluids content few numbers of bacteria. One was positive for proteus mirabilis, 3 for staphylococci. The patient showing growth of proteus after oxycyanate disinfection and one of the patients with staphylococcus aureus positive irrigation fluid did not show this kind of micro-organism in any smear before. The authors conclude that preoperative cultures do not give real security about the presence or absence of bacteria during the operation.

Bacterial Infections↗

PubMed1991

[Visual results of extracapsular cataract surgery with posterior chamber lenses].

In a total of 1663 consecutive patients best corrected visual acuity after extracapsular cataract extraction with implantation of a posterior chamber lens was determined. Average follow-up time was 21 months. Visual acuity improved from an average of 0.15 preoperatively to 0.6 postoperatively. In the absence of other ocular disorders postoperative vision averaged 0.7. The visual outcome was clearly related to the age of the patients and showed a continuous decline for operations performed after the age of 69 years.

Adult↗

PubMed1991

[Lens changes following intraocular tamponade in vitrectomy. Linear densitometric image analysis of Scheimpflug photographs 6 months after operation].

A complication arising from vitrectomy is the formation of cataract. As a result of an intra- and postoperative tamponade chosen (BSS, air, SF6-gas, silicon oil) the size and frequency of the cataract varies accordingly. 6 months after vitrectomy Scheimpflug photography and microdensitometric evaluation of the negatives were performed on 30 pairs of phacic eyes showing changes in the transparency of the lens. Following silicon oil tamponade a significant deterioration of transparency (t-test) was observed in the lens nucleus of the operated eye; in the area of the lens in front of the nucleus a marked but not significant deterioration of transparency was discovered following both silicon oil and SF6-gas tamponade. In the case of the area in front of the nucleus following SF6-gas tamponade as well as the whole of the lens following BSS or air tamponade a small but not at all significant difference in lens transparency was apparent after comparison of the operated to the non-operated eyes.

Cataract↗

PubMed1991

[Refraction after cataract surgery with posterior chamber lenses].

In an attempt to determine the accuracy of ultrasound biometry, the spherical equivalent of the refraction obtained after ECCE and implantation of a posterior chamber IOL in 1663 patients was compared to the desired refraction determined prior to surgery. Follow up time was 21 months on the average. In only 7.4% of the eyes was the exact predetermined value obtained. In 44.3% it differed toward plus and in 46.6% toward minus. The predetermined value +/- 1 dpt was obtained in 63.8% and +/- 2 dpt in 88.3% of the cases. In 11.7% of the eyes, the desired value was missed by more than +/- 2 dpt.

Eyeglasses↗

PubMed1991

[Visually evoked cortical potentials for early detection of optic neuritis in ethambutol therapy].

Ethambutol leads to chronic, severe optic neuritis with sudden onset in approximately 5-14% of all patients. Therefore, the ability of visually (pattern) evoked potentials for the early diagnosis of ethambutol-induced optic neuritis was tested. During ethambutol therapy prolonged latency was documented in 5 of 15 cases (33%). One of these 5 cases showed a reversible decrease in visual acuity. Thus, during treatment with ethambutol visually (pattern) evoked potentials may reveal a surprisingly high percentage of subclinical optic neuritis. These patients need close supervision in order to facilitate early discontinuation of the drug when neuritis develops.

Adolescent↗

PubMed1991

[Delayed resorption of subretinal fluid after pneumatic retinopexy].

Delayed resorption of pooled subretinal fluid has been reported to cause impaired visual acuity due to involvement of the macula in up to 10% of all case. In our series of 60 eyes treated consecutively with pneumatic retinopexy for retinal detachment, 9 eyes experienced delayed absorption of subretinal fluid. Only 6 eyes showed the phenomenon of pooled, localized subretinal fluid without peripheral extension to the ora serrata. The time for complete absorption of these circumscribed subretinal bullae ranged from 8 to 52 weeks (mean 22.7 weeks). Impaired visual acuity could not be detected in any of these cases. This may be due to the location of these bullae, which never involved the macula. Therefore, we do not consider the occurrence of this phenomenon to be a reason not to carry out pneumatic retinopexy.

Adult↗

PubMed1991

[Effect of vasoconstrictor eyedrops on tear volume and tear secretion].

Vasoconstrictive, alpha-sympathicomimetic eye drops are ophthalmic drugs that are extensively used. However, patients often complain of typical dry eye symptoms, especially after long-lasting application of such eye drops. In the present study, the effect of sympathicomimetic eye drops (oxymetazoline 0.026%) on the tear volume and tear flow of 16 healthy individuals was determined quantitatively by means of objective fluorophotometry. Both tear volume and tear flow were found to be significantly (p less than 0.001) decreased 3 h after instillation (tear volume: -52%; tear flow: -31%). Thus, alpha-sympathicomimetic eye drops containing oxymetazoline 0.026% lead to marked and protracted decrease in tear volume and tear flow. After frequent or long-lasting application, this fact may be responsible for severe dry eye conditions.

Adult↗

PubMed1991

[Development of lens opacities in a period of 6 months after pneumatic retinopexy].

When performing a pneumatic retinopexy, air or gas is injected into the vitreous cavity to reattach a primary, rhegmatogenous retinal detachment. SF6 gas, for examples, remains in the vitreous cavity for up to 2 weeks before it is completely absorbed. It is conceivable that the injection of SF6 gas into the vitreous cavity interferes with lens metabolism, thus causing opacities of the lens. Even minor early changes in lens transparency can be monitored by Scheimpflug photography. Two months after performing a pneumatic retinopexy, 31 out of 100 consecutive eyes showed a loss of lens transparency, which was not pronounced or statistically significant. Six months after surgery the loss of transparency was more pronounced in all lens layers, increasing from the front to the back. The increment was statistically significant for the anterior lens cortex. Further investigations are needed to determine whether lens changes are the result of the intraocular tamponade with SF6 gas or are related to other factors, such as the surgical maneuver itself.

Cataract↗