Cerebral Oximetry as an Auxiliary Diagnostic Tool in the Diagnosis of Brain Death.

AIM: To investigate the efficacy of cerebral oximetry (CO) as an auxiliary diagnostic tool in brain death (BD). MATERIALS AND METHODS: This observational case-control study was performed on patients with suspected BD. Patients with diagnosis of BD confirmed by the brain death committee were enrolled as the BD group and other patients as the non-BD group. CO monitoring was performed at least 6 h, and cerebral tissue oxygen saturation (ScO2) parameters were compared. RESULTS: Mean ScO2 level in the BD group was lower than non-brain-dead patients: mean difference for right lobe = 6.48 (95% confidence interval [CI] 0.08-12.88) and for left lobe = 6.09 (95% CI -0.22-12.41). Maximum ScO2 values in the BD group were significantly lower than the non-BD group: mean difference for right lobe = 8.20 (95% CI 1.64-14.77) and for left lobe = 9.54 (95% CI 3.06-16.03). The area under the curve for right lobe maximum ScO2 was 0.69 (95% CI 0.55-0.81) and for left lobe was 0.72 (95% CI 0.58-0.84). CONCLUSION: Maximum ScO2 in brain-dead patients at CO monitoring is significantly low. However, this cannot be used to differentiate brain-dead and non-brain-dead patients. CO monitoring is therefore not an appropriate auxiliary diagnostic tool for confirming BD.

Vessel diameter study: intravitreal vs posterior subtenon triamcinolone acetonide injection for diabetic macular edema.

PurposeTo detect and compare the vessel diameter effect of intravitreal vs subtenon injection of triamcinolone for diabetic macular edema (DME).MethodsSixty patients with DME who underwent triamcinolone injection either intravitreally (N=30) or under the tenon capsule (N=30) were included. Non-injected fellow eyes served as control. The main outcome measures were central retinal artery equivalent (CRAE), central retinal vein equivalent (CRVE), and artery-vein ratio (AVR).ResultsIn the intravitreal group, pre-injection mean CRAE (147.07 µ) decreased to 141.03 µ at 1 week and to 139.43 µ at 1 month (P<0.001) while baseline CRVE (209.61 µ) decreased initially to 198.85 µ at 1 week then to 198.49 µ at 1 month (P<0.001). In the subtenon group, pre-injection CRAE (152.18 µ) decreased to 149.49 µ at 1 week and to 147.47 µ at 1 month (P=0.017), while baseline CRVE (215.60 µ) decreased initially to 208.69 µ at 1 week then to 207.25 µ at 1 month (P=0.003). Pre-injection AVR values did not change at 1 week and at 1 month in both injection groups (P=0.66 and P=0.196, respectively). In the control group, none of the 3 parameters changed throughout the study period compared to the baseline (P>0.28).ConclusionIn eyes with DME, both intravitreal and subtenon triamcinolone injection led to a significant constriction of retinal arteries and veins.

Retinal thickness change in relation to visual acuity improvement after 23-gauge vitrectomy for idiopathic epimacular membrane.

PURPOSE: To assess the course of macular thickness change in relation to visual acuity improvement, in patients being operated for idiopathic epimacular membrane by 23-gauge pars plana vitrectomy. MATERIALS AND METHODS: The clinical charts of 21 eyes of 19 consecutive patients (9 male and 10 female) were assessed retrospectively. Postoperatively, patients were followed up by best-corrected Snellen visual acuity (BCVA), a thorough ophthalmological examination, including fundoscopy, retinal thickness, and macular morphology as demonstrated by optical coherence tomography. The main outcome measures of the study were changed in central macular thickness (CMT)and visual acuity during the follow-up period. RESULTS: The mean duration of follow-up was 15.9 ± 1.0 months (range 12-24 months). Mean baseline BCVA improved from 0.22 ± 0.03 (decimal fraction) to 0.50 ± 0.07 at the last visit (P = 0.001), whereas baseline CMT (408 µm) decreased to 283 µm at final examination (P = 0.001). During the follow-up, 10 eyes (47%) achieved 0.5 or better BCVA. The first significantly lower CMT readings were obtained at third-month visit while BCVA showed an improvement with the significant difference following 9 months after the surgery. In total, 8 out of 11 phakic eyes underwent cataract extraction with a mean of 6.8 months (range 1-12 months). CONCLUSIONS: After a successful epimacular membrane removal, functional recovery takes at least 9 months in comparison to much early resolution in macular oedema that was evident at third month following the surgery.

Surgical outcome of coaxial phacoemulsification with torsional ultrasound after a 2.4 mm versus 3.2 mm clear corneal temporal incision.

PURPOSE: This study aimed to evaluate and compare outcomes of phacoemulsification surgery with purely torsional ultrasound in coaxial small incision procedures. METHODS: This study was a prospective observational series of 50 eyes of 50 patients with age-related cataracts. There were two groups each with 25 eyes. Group 1 eyes were treated with microcoaxial phacoemulsification using a 2.4 mm temporal clear corneal incision; group 2 eyes were treated with phacoemulsification using a 3.2 mm temporal clear corneal incision. Both groups underwent a standardised surgical procedure using purely torsional ultrasound. Outcome measures were best corrected visual acuity, percentage increase in postoperative corneal thickness, and surgically-induced astigmatism assessed at day 1, week 1, month 1 and month 3 postoperatively. RESULTS: Both groups were comparable with respect to age, cataract grading and intraoperative parameters such as cumulative dissipated energy and irrigation volume. The only statistically significant outcome difference was surgically induced astigmatism at postoperative day 1 (higher in group 2). Intraoperative and early postoperative complications were similar in both groups. CONCLUSIONS: Coaxial phacoemulsification with purely torsional ultrasound produced satisfactory results for 2.4 mm and 3.2 mm incisions. There were no differences in outcomes between groups.

Alterations in central retinal sensitivity after intravitreal triamcinolone injection for diffuse diabetic macular edema.

PURPOSE: To evaluate alterations in central retinal sensitivity following intravitreal triamcinolone injection in patients with diffuse diabetic macular edema that persisted after laser treatment. METHODS: Fourteen eyes of 14 patients that received 4 mg 0.1 cc intravitreal triamcinolone underwent macular threshold test using computerized visual field analyzer before and after 1, 2, 3, and 5 months of triamcinolone injection. Pre- and postinjection values of total defect depth, total threshold, and best-corrected visual acuity were compared and correlated. RESULTS: At the last follow-up, compared to baseline, visual acuity improved from 1.4+/-0.4 (logMAR, mean +/- standard deviation) to 1.0+/0.4 (p=0.01). Total defect depth tended to recover from 148+/-64 dB to 121+/-48 dB (p=0.12), and total threshold tended to increase from 241+/-87 dB to 271+/-68 dB (p=0.16), but these values did not reach significance. There was a significant correlation between baseline and 5 months postinjection values of total defect depth (rho=0.60, p=0.02), and of total threshold of light sensitivity (rho=0.55, p=0.04). CONCLUSIONS: Best-corrected visual acuity was found improved in patients with diabetic macular edema 5 months after triamcinolone injection. Improvement in central retinal sensitivity did not reach significant level at the last follow-up. Macular threshold test may be a valuable tool in the follow- up of patients with diffuse diabetic macular edema after intravitreal triamcinolone injection.

Comparison of ICG-assisted ILM peeling and triamcinolone-assisted posterior vitreous removal in diffuse diabetic macular oedema.

AIM: To compare the effect of indocyanine green (ICG)-assisted internal limiting membrane (ILM) peeling and triamcinolone acetonide-assisted posterior vitreous removal on visual acuity in patients with diffuse diabetic macular oedema (DMO). METHODS: In total, 24 patients with diffuse DMO who underwent pars plana vitrectomy were included in this study. In all, 11 patients (mean age 57 years) were performed ICG-assisted ILM peeling; while 13 patients (mean age 54 years) underwent triamcinolone-assisted posterior vitreous removal. Patients from two different treatment regimens were compared in terms of best-corrected visual acuity (BCVA) at postoperative sixth months. RESULTS: In ICG-assisted ILM peeling group, preoperative BCVA (1.3+/-0.4, mean+/-SD, logMAR) improved postoperatively to 0.9+/-0.5 (P=0.011). In eyes underwent triamcinolone-assisted posterior vitreous removal, baseline BCVA of 1.4+/-0.4 improved to 1.0+/-0.5 (P=0.007). There was no difference between baseline as well as postoperative sixth-month BCVA results of both groups (P=0.59 and P=0.57, respectively). CONCLUSIONS: Triamcinolone-assisted posterior vitreous removal and ICG-assisted ILM peeling have the same effect in terms of postoperative BCVA in patients with diffuse DMO.

Plasma malondialdehyde and nitric oxide levels in age related macular degeneration.

AIMS: To evaluate alteration of plasma malondialdehyde (MDA) and nitric oxide (NO) levels in patients with exudative age related macular degeneration (ARMD). METHODS: Plasma nitrite plus nitrate concentrations as an index of plasma NO levels and plasma MDA level as a marker of lipid peroxidation were measured in patients with exudative ARMD and age and sex matched healthy subjects. RESULTS: Significantly higher MDA and lower NO levels were detected in plasma of patients with ARMD compared with their controls (p=0.01, p=0.001, respectively). CONCLUSION: The results may support involvement of oxidative damage and vascular theory in the pathogenesis of ARMD as part of the ageing process.

Effect of Ca(2+)-free and Mg(2+)-free BSS Plus solution on the retinal pigment epithelium and retina in rabbits.

PURPOSE: To determine whether intravitreal irrigation with Ca(2+)-free and Mg(2+)-free BSS Plus (Alcon Laboratory, Fort Worth, Texas) solution alters the adhesiveness between the retinal pigment epithelium and the retina of rabbits. METHODS: Thirty-four eyes of 34 Dutch pigmented rabbits underwent lensectomy and vitrectomy. Subsequently, the vitreous cavity of 24 eyes was irrigated with Ca(2+)-free and Mg(2+)-free BSS Plus solution for 10 or 20 minutes. The other 10 eyes were irrigated with BSS Plus solution for 20 minutes as controls. To determine the adhesiveness between the retinal pigment epithelium and retina, a retinal detachment was produced in 12 of the 34 eyes. The apical surface of the retinal pigment epithelium and the photoreceptor outer segments were examined by scanning electron microscopy. Retinal physiology was assessed by electroretinography and retinal morphology by light microscopy. RESULTS: After retinal detachment was produced, the number of cone sheaths on the apical surface of the retinal pigment epithelium after irrigation with Ca(2+)-free and Mg(2+)-free BSS Plus solution for 20 minutes (33 +/- 15, mean +/- SD) was significantly less than the number of cone sheaths on the apical surface of the retinal pigment epithelium of eyes after irrigation with BSS Plus solution for 20 minutes (120 +/- 50) or the number of cone sheaths on the apical surface of the retinal pigment epithelium of eyes after 10 minutes of irrigation with Ca(2+)-free and Mg(2+)-free BSS Plus solution (115 +/- 49; P =.02). The b-wave amplitudes in the eyes irrigated with Ca(2+)-free and Mg(2+)-free BSS Plus solution for 20 minutes were depressed compared with the b-waves in eyes irrigated with BSS Plus solution for 20 minutes on the first postoperative day (P =.03). After the third postoperative day, there was no significant difference in the b-waves (P >.06). Light microscopy demonstrated no morphologic abnormalities after the use of both solutions. CONCLUSIONS: Intravitreal irrigation with Ca(2+)-free and Mg(2+)-free BSS Plus solution for 20 minutes altered the adhesion between the retinal pigment epithelium microvilli and retinal outer segments and made the creation of retinal detachment less traumatic. These results suggest that Ca(2+)-free and Mg(2+)-free BSS Plus solution may be of clinical value for the creation of an intentional retinal detachment for foveal translocation surgery.

Incidence of keratoconus in subjects with vernal keratoconjunctivitis: a videokeratographic study.

PURPOSE: To detect the incidence of keratoconus by videography in patients with vernal keratoconjunctivitis (VKC) and to evaluate the clinical characteristics of VKC associated with keratoconus. DESIGN: a prospective, cross-sectional (prevalence) study. PARTICIPANTS: Eighty-two consecutive subjects with the diagnosis of VKC. METHODS: Both eyes of VKC subjects were investigated by videokeratography in comparison with slit-lamp biomicroscopy and keratometry. To detect keratoconus, corneal topography maps were examined with modified Robinowitz-McDonnell test. MAIN OUTCOME MEASURES: In this test, maps with central corneal power greater than 47.2 diopters and/or the inferosuperior asymmetry value greater than 1.4 were considered to have a keratoconus pattern. The findings of VKC were also recorded, RESULTS: The distribution of clinical forms of VKC were as follows: 46.34% mixed, 43.90% palpebral, and 9.76% limbal types. Twenty-six (31.7%) of 82 subjects had complications with keratopathy such as pseudo-genontoxon, punctate keratitis, and shield ulcer. Forty-four eyes (26.8%) were detected as keratoconus by quantitative evaluation of videokeratography maps. 14 eyes (8.5%) by biomicroscopy, and 30 eyes (18.3%) by keratometry. The increased incidence of keratoconus was associated with male gender, long-standing disease, mixed and palpebral forms, and advanced corneal lesions. CONCLUSIONS: The higher incidence of keratoconus in our study compared with the previous reports may result from early detection of mild keratoconus by interpretation of color-coded videokeratographic maps with a sensitive quantitative method.

Comparison of subretinal fluid levels of two 0.3% ciprofloxacin-containing eye drops.

PURPOSE: Two ophthalmic solutions of 0.3% ciprofloxacin eye drops are available in Turkey: Ciloxan and Siprogut. A previous study by the same authors was the first to report vitreous penetration of ciprofloxacin-containing eye drops. The aim of the present study was to compare the levels of drug found in the subretinal fluid by the two products following local administration. METHODS: Forty-three patients undergoing conventional retinal detachment surgery received either Ciloxan (22 patients) or Siprogut (21 patients). Beginning 6 h before surgery, two drops of solution were instilled onto the operative eye every 30 min for the first 3 h and then hourly for the next 3 h. Subretinal fluid samples were collected 30 min after administration of the last dose and were assayed for ciprofloxacin levels using a method involving high-performance liquid chromatography with fluorometric detection. RESULTS: The minimum and maximum subretinal fluid concentrations measured were 0.11 microg/mL and 0.65 microg/mL, respectively, with Ciloxan, and 0.08 microg/mL and 0.62 microg/mL, respectively wth Siprogut. There was no statistical difference between the subretinal fluid ciprofloxacin levels of the two products. The subretinal fluid drug evels attained by both products were below the minimum inhibitory concentrations of common ocular pathogens. CONCLUSIONS: Ciloxan and Siprogut can penetrate subretinal fluid. The ocular bioavailability of ciprofloxacin after local administration is equivalent for both pharmaceutical products.

Effect of caffeic acid phenethyl ester on corneal neovascularization in rats.

PURPOSE: Caffeic acid phenethyl ester (CAPE), a biologically active component of propolis from honeybee hives, has potent antiinflammatory and antioxidant properties. We aimed to evaluate the ability of topically applied CAPE in comparison with known steroidal (dexamethasone sodium phosphate) and nonsteroidal (indomethacin) topical agents to reduce corneal neovascularization (CNV) induced by silver nitrate cauterization in rats. METHODS: Following silver nitrate cauterization on both eyes, male rats were randomly assigned to the study and control groups, each consisting of ten rats. The inhibitory effects of the test drugs against a placebo (isotonic saline) on CNV were tested and compared to each other using a previously described method in which extent of neovascularization and burn stimulus intensity were scored by a masked examiner. Briefly, burn stimulus intensity was scored from 0 to +3 according to the height of blister from corneal surface, and extent of neovascularization was recorded from 0 to +6 according to the distance from limbus to the end point of CNV toward the central corneal burn. Results. The mean burn stimulus score were not different among the groups (P = 0.807). Percent inhibition of CNV compared to the placebo control and its significance were 31.5 %, P = 0.011 for indomethacin; 56 %, P < 0.001 for dexamethasone; and 52 %, P < 0.001 for CAPE. Dexamethasone was significantly (P < 0.05) more effective than indomethacin in inhibition of neovascular growth. CAPE was found to be superior (P < 0.05) to indomethacin and almost as effective as (P > 0.05) dexamethasone in reducing CNV. Conclusion. Topically applied CAPE was demonstrated to have an inhibitory effect, comparable to that of topical dexamethasone, on CNV in this rat model. Antiinflammatory and antioxidant properties of CAPE may contribute to its suppression on CNV.

nm23 Expression in choroidal melanoma.

nm23 protein expression of choroidal melanoma was investigated to determine its relationship with clinical and histopathological characteristics of the tumour. Thirty-four consecutive choroidal melanoma patients were examined by immunohistochemistry. Although age, sex, tumour cell type, tumour size, pigmentation, necrosis, apoptosis and tumour lymphocytic infiltration were not correlated with nm23 protein expression, tumours with low percentages of nm23-positive cells revealed higher nuclear grades and predominant mitotic figures. nm23 may be associated with melanoma progression, but there is no proof that it plays a role in the metabolic process of the tumour.

Subretinal fluid levels of topical, oral, and combined administered ciprofloxacin in humans.

AIMS: To investigate the subretinal fluid (SRF) penetration of ciprofloxacin following topical, oral, and combined administration. METHODS: 34 patients undergoing conventional retinal reattachment surgery were randomly assigned to three groups. Twelve patients received topical ciprofloxacin, 11 patients received oral ciprofloxacin, and the other 11 patients received combined drug administration. SRF drug level was measured by using high performance liquid chromatography method. RESULTS: The highest drug concentrations of all tested modes were attained following combined administration and lowest following topical administration (p<0.001). The SRF drug concentration following oral administration was also significantly higher than that of topical administration (p<0.001). Concentrations after oral and combined administration did not differ significantly (p = 0.217). CONCLUSIONS: Topical ciprofloxacin can penetrate SRF. Ocular bioavailability of ciprofloxacin in SRF after oral and combined administration is equivalent.

Bilateral cataract surgery in adult and pediatric patients in a single session.

PURPOSE: To evaluate the results of bilateral simultaneous cataract surgery in adult and pediatric patients under local or general anesthesia. SETTING: Department of Ophthalmology, Inönü University, Turgut Ozal Medical Center, Malatya,Turkey. METHODS: Eighty-two eyes of 41 patients were included in the study. Twelve of 17 pediatric patients with congenital cataract had bilateral simultaneous lensectomy, posterior capsulotomy, and anterior vitrectomy; 5 patients, aged 10 to 19 years, had bilateral extracapsular cataract extraction (ECCE) with posterior chamber intraocular lens (PC IOL) implantation. Forty-eight eyes of 24 adult patients had bilateral simultaneous ECCE with primary (43 eyes) or secondary (5 eyes) PC IOL implantation. Local anesthesia was administered to 20 adult patients by retrobulbar injection; the other cases were performed using general anesthesia. The procedures were treated as 2 separate surgeries in the same session; care was taken to ensure surgical asepsis. RESULTS: No serious intraoperative complications occurred such as posterior capsule rupture, vitreous loss, endophthalmitis, and anesthesia-related problems. Of patients tested, 84.4% achieved a final best corrected visual acuity of 6/12 or better and 31.0%, of 6/6 or better. CONCLUSIONS: Simultaneous bilateral cataract surgery was not associated with an increased rate of complications, and visual results were good. If strict rules of surgical asepsis are followed, this may be a useful option in a variety of bilateral cases using general or local anesthesia.

Small incision extracapsular cataract surgery with manual phacotrisection.

PURPOSE: To evaluate the safety and efficacy of small incision extracapsular cataract extraction (ECCE) using the manual phacotrisection technique. SETTING: Department of Ophthalmology, Turgut Ozal Medical Center, InönüUniversity, Malatya, Turkey. METHODS: Fifty-nine eyes of 54 patients had small incision ECCE by the manual phacotrisection technique. Mean follow-up was 10 months. After capsulorhexis and hydrodissection were performed, the endonucleus was prolapsed into the anterior chamber and trisected using an anteriorly positioned triangular trisector and posteriorly placed solid vectis. Pieces were extracted with a forceps through a small incision. RESULTS: Postoperatively, best spectacle-corrected visual acuity of 20/40 or better was achieved in 48 eyes (83%) and of 20/25 or better in 28 eyes (47%). The most frequent intraoperative complication was posterior capsule rupture (n = 5). Of eyes that developed posterior capsule rupture, 3 had vitreous loss and 2 had implantation of an anterior chamber intraocular lens (IOL). In 44 eyes, the IOL was implanted in the bag and in 12 eyes, in the ciliary sulcus. The most significant postoperative complication was transient corneal edema, which developed in 32 eyes (54%). No permanent complications (e.g., corneal endothelial decompensation) occurred in any case. CONCLUSIONS: Manual phacotrisection has several advantages such as nucleus safety, less dependence on assistant personnel, the elimination of the phaco machine, and cost effectiveness.