PubMed Health⌕ Search

Biomedical subjects

E Gürsel

Publications and source records attributed to E Gürsel.

10 recordsLinked to original sources

Penetration of topical fluconazole into human aqueous humor.

The purpose of this study was to determine the aqueous levels and pharmacokinetics of topical fluconazole 0.2% upon single and multiple drop applications. Forty-nine patients undergoing cataract surgery were given topical fluconazole 0.2%. They either received single drop or a loading dose of 1 drop per 5 min for 20 min. Aqueous samples were obtained during surgery 5, 15, 30, 45 and 60 min after the last drop. The samples were analysed by high-pressure liquid chromatography to determine aqueous concentrations. After single and loading dose applications peak aqueous levels were achieved at 15 min (3.35 +/- 0.64 and 7.13 +/- 0.79 microg ml(-1), respectively). Both had a steady decrease in concentration at 30, 45 and 60 min down to 4.06 +/- 0.37 microg ml(-1)with loading dose and undetectable levels with single dose application. Comparing the concentrations with the minimum inhibitory concentrations (MIC) of yeasts determined by the National Committee for Clinical Laboratory Standards showed that concentrations achieved with single dose applications were higher than MICs of Candida albicans and Candida parapsilosis and concentrations achieved after loading dose applications were higher than MICs of C. parapsilosis, C. albicans and Candida tropicalis. We concluded that topical fluconazole 0.2% penetrates into the aqueous humor in concentrations that satisfy MICs of most of the Candida strains. It can be a good alternative to Amphotericin B for treatment of Candida keratitis.

Administration, Topical↗

Protein C, protein S and antithrombin III deficiencies in retinal vein occlusion.

PURPOSE: The role of decreased levels of protein C, protein S and antithrombin III were investigated in patients with branch and central retinal vein occlusion. METHODS: Forty-five patients with retinal vein occlusion and 20 healthy subjects as a control group was studied. Fourteen patients (31%) had central retinal vein occlusion and 31 (69%) had branch retinal vein occlusion. The concentrations of protein C, protein S and antithrombin III were measured. RESULTS: Plasma levels of protein C, protein S and antithrombin III were not reduced in the control group. Six of the 14 central retinal vein occlusion cases and 3 of the 31 retinal branch vein occlusion cases had decreased levels of protein C. One of the 14 central retinal vein occlusion cases and 1 of the 31 retinal branch vein occlusion cases had decreased levels of protein S. Antithrombin III was reduced in 1 patient of the 31 retinal branch vein occlusions. We found statistically significant differences for number of cases with protein C deficiency between the central retinal vein occlusion cases and the branch retinal vein occlusion cases (p<0.05). CONCLUSION: Deficiency of anticoagulant proteins, especially protein C, may play a role in the etiology of retinal vein occlusion. Measurement of these parameters may be useful in preventing venous thrombosis elsewhere in the body.

Biomarkers↗

Divergence paralysis & intracranial hypertension due to neurobrucellosis. A case report.

CASE REPORT: A 22 year old female presented with sudden onset of uncrossed diplopia at distance, intracranial hypertension, esotropia and was evaluated. Microbiological tests of CSF and sera showed for brucellosis and the patient received therapy for this and her intracranial hypertension. The papilledema, headache, esotropia and diplopia all disappeared after therapy. CONCLUSIONS: Diagnostic tests for brucella must be considered for patients who have divergence palsy and papilledema, especially those living in endemic areas.

Acetazolamide↗

A topical or oral carbonic anhydrase inhibitor to control ocular hypertension after cataract surgery.

PURPOSE: To compare the effects of oral acetozolamide and topical 2% dorzolamide to prevent ocular hypertension after cataract surgery. METHODS: This prospective, randomized study comprised 62 consecutive patients who had extracapsular cataract extraction and posterior chamber intraocular lens implantation. Patients received either oral acetozolamide (Diazomide) 250 mg three times daily or topical dorzolamide 2% (Trusopt) three times daily, for three days. Intraocular pressures (IOP) were measured by Goldmann applanation tonometry preoperatively and 16, 40, 64 hours postoperatively. RESULTS: IOP in the dorzolamide group peaked at 16 hours and had returned to preoperative values by 40 hours. In the acetozolamide group mean IOP was significantly higher than preoperative values at 16, 40 and 64 hours (p<0.05). At all three postoperative measurement times, mean IOP was significantly higher in the acetozolamide group (p<0.05). CONCLUSIONS: Topical dorzolamide 2% offers better IOP control than oral acetozolamide to prevent ocular hypertension after cataract surgery.

Acetazolamide↗

Risk factors for vitreous loss in cataract surgery.

PURPOSE: To evaluate the risk factors for posterior capsule rupture with or without vitreous loss (PCR +/- VL) in extracapsular cataract extraction (ECCE). METHODS: The charts of 2794 consecutive patients who had ECCE with or without intraocular lens implantation between January 1992 and December 1997 were reviewed retrospectively. Probable risk factors included age, sex, operated eye (right or left), presence of diabetes mellitus, systemic hypertension, history of vitreous loss in the other eye (if operated), type of cataract, axial length of the eye, preoperative visual acuity, glaucoma, presence of pseudoexfoliation, preoperative shallow anterior chamber and experience of surgeon (resident, general ophthalmologist, cataract surgeon). We compared 192 patients who had PCR +/- VL with complete data and 275 randomly selected patients who had no complications, using multiple logistic regression analysis. RESULTS: Two hundred and fifty-four patients (9.09%) had PCR and 197 (7.05%) had PCR + VL. The surgeon's experience (p < 0.0005), glaucoma (p < 0.005), type of cataract (p < 0.005), presence of pseudoexfoliation (p < 0.05) and systemic hypertension (p < 0.05) were significant risk factors. CONCLUSIONS: Patients with risk factors such as glaucoma, pseudoexfoliation, traumatic cataract and systemic hypertension should be operated by experienced surgeons.

Adolescent↗

Asteroid hyalosis.

PURPOSE: This study evaluated ocular and systemic diseases in patients with asteroid hyalosis and compared axial lengths of asteroid hyalosis patients with the normal population. METHODS: The examination of 26 patients with asteroid hyalosis consisted of complete history, complete ocular examination, blood pressure and laboratory studies in order to detect systemic diseases, A and B scan ultrasonography to measure axial lengths and to detect posterior vitreous detachment. RESULTS: All patients had unilateral asteroid hyalosis; 10 (38.5%) were symptomatic. Eight patients (20.5%) had type II diabetes mellitus, 13 (33.3%) patients had systemic arterial hypertension and 7 (18%) had atherosclerotic heart disease; 5 (12.8%) had hyperlipidemia and 6 (15.4%) had hypercholesterolemia. Posterior vitreous detachment was found in 3 (11.5%) patients with asteroid hyalosis, and 6 patients in the control group (23.1%) had posterior vitreous detachment (p<0.01). In patients with asteroid hyalosis, the mean axial length difference between two eyes was 0.32 +/- 0.06, against 0. 10 +/- 0.02 in the control group (p<0.01). CONCLUSION: Asteroid hyalosis may be found together with systemic diseases and such patients must be evaluated systematically for diabetes mellitus, hypertension and hyperlipidemia. Asteroid hyalosis can also cause artefactual lowering of axial length measurement, leading to significant error in calculations of intraocular lens power. This must be kept in mind before cataract surgery.

Aged↗

Eyelid malpositions after cataract surgery.

PURPOSE: To estimate the incidence and the factors that may play a role in the etiology of eyelid malpositions after cataract extraction. METHODS: We followed up 124 patients for six months after cataract extraction. Palpebral aperture, levator function, height of the upper lid crease, lower eyelid laxity and position of the punctums were recorded preoperatively and postoperatively. Post-cataract ptosis was defined as a 2 mm or greater drop in the lid margin after correcting for any change in the fellow eye. RESULTS: None of the patients developed ectropion or entropion, but five (4%) developed punctal ectropion after surgery. The incidence of post-cataract ptosis was 7.3% at six months. Age, sex, preoperative measurements of levator function, lid crease and dermatochalasis were not predictive for the development of ptosis at six months. However, there was a significant difference in the preoperative palpebral fissure width between the patients with ptosis and those without (p<0.05). There was a positive correlation between the mean volume of local anesthetic and the degree of ptosis on the first postoperative day (p<0.05, r: 0.1873). The presence and amount of ptosis on the first postoperative day was the best predictor of post-cataract ptosis at six months (p<0.001). CONCLUSIONS: Several factors are involved in the development of post-cataract ptosis. Temporary ptosis may be related to the myotoxicity of the local anesthetic. The presence of ptosis on the first postoperative day is the best predictor for the development of ptosis at six months.

Adult↗

The penetration of ofloxacin into human aqueous humor given by various routes.

This study was designed to measure the concentration of ofloxacin in aqueous humor after topical, oral and intravenous administration in 50 patients undergoing cataract extraction. In Group 1, ofloxacin 0.3% eyedrops were topically instilled ten times and the aqueous humor concentration was 2.73 +/- 0.88 microg/ml. In Group 2, ofloxacin 0.3% eyedrops were topically instilled six times and the aqueous humor concentration was 0.84 +/- 0.61 microg/ml. Aqueous humor concentration 12 hours after 200 mg oral dose in Group 3, was 0.38 +/- 0.12 microg/ml. In Group 4, patients were given ofloxacin as a single intravenous 200 mg dose and the aqueous humor concentration 2 hours after the end of infusion was 0.45 +/- 0.11 microg/ml. Concentrations were determined by high performance liquid chromatography (HPLC) with fluorescence detection. There was a significant difference between Group 1 and the other groups, but not between Group 2 and Groups 3, 4. It was concluded that ofloxacin penetrates the corneal and the blood-aqueous barriers and can achieve good aqueous levels when given topically and systematically. Ofloxacin can be applied topically for external bacterial infections such as conjunctivitis and keratitis. Systematically administered ofloxacin reached higher levels than the MIC for some bacteria which cause endophthalmitis.

Administration, Oral↗

Color Doppler imaging of the retrobulbar circulation in age-related macular degeneration.

PURPOSE: The aim of this study was to assess hemodynamic changes in the retrobulbar circulation in patients with age-related macular degeneration (ARMD). METHODS: Color Doppler imaging was used to calculate blood flow velocities and vascular resistance of the central retinal artery, short posterior ciliary artery and ophthalmic artery in patients with ARMD and in control patients. RESULTS: The average peak systolic velocity was significantly lower in the central retinal artery (p < 0.001), posterior ciliary artery (p < 0.001) and ophthalmic artery (p < 0.01) of the patients with ARMD than in control. End-diastolic blood flow velocities in the retrobulbar arteries of ARMD patients were also significantly lower (p < 0.001) than controls. Gosling's pulsatility index was significantly higher in the ophthalmic artery (p < 0.01) and posterior ciliary artery (p < 0.001) of eyes with ARMD. In addition, the resistivity index was significantly higher in all retrobulbar arteries (p < 0.001) of these patients. CONCLUSIONS: The hemodynamic abnormalities in the retrobulbar circulation suggest that vascular impairment may play a role in the pathogenesis of ARMD.

Aged↗