Dimitrios Papaconstantinou

Foveal thickness after phacoemulsification as measured by optical coherence tomography

Background Despite a significant body of research, no consistency on postoperative foveal thickness as measured by optical coherence tomography (OCT), can be recorded. The purpose of our study was to evaluate the effect of uncomplicated cataract surgery in the thickness of the retina in the foveal area during the early postoperative period. Methods In a prospective study, 79 eyes were assessed by OCT, on day 1, and weeks 2 and 4 after uncomplicated phacoemulsification with intraocular lens implantation in the Athens University Clinic. The outcome measure was the thickness of the retina in the foveal area. Results The thickness of the retina preoperatively is significantly smaller (150.4 ± 18.8) (p < 0.05) than the thickness of the retina on day 1 (171.8 ± 21) and week 2 (159.7 ± 19) and returned to the initial levels on week 4 (152 ± 17.1). The estimated correlation coefficients between preoperative and postoperative thickness of the retina were significant (p < 0.05). Conversely, no association was found between postoperative visual acuity and thickness of the retina, neither between the phacoemulsification energy and retinal thickness. Operation time, although inversely related with postoperative visual acuity, was not associated with the thickness of the retina. Conclusions Following phacoemulsification, an increase in the foveal thickness was detected in the early postoperative period, quantified and followed up by OCT. The foveal thickness returned to the preoperative level, 1 month following surgery in our study. No association was shown between intraoperative parameters and increased postoperative retinal thickness.

Visual Outcomes After Descemet Membrane Endothelial Keratoplasty Versus Descemet Stripping Automated Endothelial Keratoplasty-Comparison of Specific Matched Pairs.

Purpose: To compare visual rehabilitation after Descemet membrane endothelial keratoplasty (DMEK) and Descemet stripping automated endothelial keratoplasty (DSAEK) for Fuchs endothelial dystrophy. Methods: The medical records of patients undergoing endothelial keratoplasty were retrospectively evaluated. A DMEK (n = 25 eyes) and a DSAEK (n = 25 eyes) group were formed. Specific matched pairs consisting of 1 DMEK and 1 DSAEK eye with the same preoperative best spectacle-corrected visual acuity (BSCVA) were built and compared with regard to visual rehabilitation, subjective refraction, central corneal thickness, and endothelial cell density. Results: Preoperative median BSCVA (logarithm of the minimal angle of resolution) was for both groups 0.7 (range, 0.2–1.70). At 12 months, median BSCVA was 0.0 (range, −0.08 to 0.7) after DMEK and 0.3 (range, 0.1–0.52) after DSAEK (P < 0.001). The spherical equivalent changed after DMEK from 0.0 D (range, −2.75 to 4.63 D) to 0.5 D (range, −1 to 2.5 D) and after DSAEK from −0.32 D (range, −2.50 to 1 D) to 0.63 D (range, −2.38 to 2 D). Central corneal thickness decreased from 718 &mgr;m (range, 566–1041 &mgr;m) to 533 &mgr;m (range, 460–605 &mgr;m) after DMEK and from 650 &mgr;m (range, 527–749 &mgr;m) to 605 &mgr;m (range, 486–650 &mgr;m) after DSAEK. Endothelial cell density decreased from 2448 cells/mm2 (range, 2106–3000 cells/mm2) to 1263 cells/mm2 (range, 589–2282 cells/mm2) after DMEK and from 2348 cells/mm2 (range, 2156–2781 cells/mm2) to 1327 cells/mm2 (range, 664–1972 cells/mm2) after DSAEK. Conclusions: DMEK patients showed faster rehabilitation and higher BSCVA at all postoperative visits; however, the decline in grafts endothelial cell count and change in the spherical equivalent were similar for both procedures.

The effect of prostaglandin analogs on the biomechanical properties and central thickness of the cornea of patients with open-angle glaucoma: a 3-year study on 108 eyes.

Purpose To evaluate the effect of prostaglandin analogs (PGAs) on the biomechanical properties (corneal hysteresis [CH], corneal resistance factor [CRF]) and central corneal thickness (CCT) of patients with open-angle glaucoma. Methods A total of 108 eyes were prospectively included for repeated measurements of intraocular pressure (IOP) with Goldmann applanation tonometry (GAT) and ocular response analyzer (ORA), CCT, followed by CH and CRF measurements by the ORA, during the same visit. Of these, 66 were treated with latanoprost, and 42 were treated with latanoprost and timolol. IOP, CH, CRF, and CCT were measured before treatment and at 6-month intervals. Results It appears that under local PGA treatment, IOP values decreased and CH and CCT significantly increased, whereas CRF did not. CCT slightly but significantly increased at all time points of the study (0.50–3.00 μm and 1.50–5.50 μm), and we observed a constant significant increase in CH (0.4–0.7 mmHg and 0.65–0.95 mmHg). Concerning the correlation of GAT IOP with CCT and CH, it was found that at the time points 0, 1, and 2 there were statistically significant correlations. Conclusion The changes of CCT and CH under PGA treatment in clinical practice may influence IOP measurements and patient follow-up significantly. This should be investigated further to confirm the relationship between corneal properties and treatment of open-angle glaucoma.

The effect of subconjunctival ranibizumab on corneal and anterior segment neovascularization: study on an animal model.

Purpose To evaluate the effect of subconjunctival anti—vascular endothelial growth factor (VEGF) ranibizumab on corneal and anterior segment neovascularization. Methods In this experimental study and laboratory investigation, chemical cauterization was utilized to induce corneal neovascularization in 16 rabbits randomly divided in 2 equal groups. Cauterized eyes were either treated with 0.1 mL (1 mg) of subconjunctival ranibizumab or administered a sham injection. A third group of 4 rabbits served as control for side effects after ranibizumab administration. All animals were monitored daily for 14 days and the extent of corneal scarring and neovascularization was measured on days 1, 7, and 14. After enucleation, ocular tissues were separated under a surgical microscope and VEGF levels were measured with ELISA. Statistical analysis was performed to compare the extent of corneal neovascularization and VEGF levels between treated and untreated eyes. Results Subconjunctival ranibizumab inhibited corneal neovascularization significantly both in the first and the second week compared to untreated controls (p = 0.006 and p = 0.001, respectively). The VEGF levels were significantly lower in all anterior segment tissues like the cornea, iris, aqueous humor, and conjunctiva of the treated eyes (p<0.01). The reduction of VEGF levels ranged from 19% to 73% in different ocular tissues. Corneal scarring was not significantly affected by anti-VEGF treatment (p = 0.7). No side effects were noticed. Conclusions Early subconjunctival administration of ranibizumab may successfully inhibit alkali-induced corneal neovascularization in an animal model. Subconjunctival ranibizumab reduces VEGF levels significantly not only in the cornea and the bulbar conjunctiva but also in the aqueous humor and the iris.

The effect of prostaglandin analogues on central corneal thickness of patients with chronic open‐angle glaucoma: a 2‐year study on 129 eyes

Purpose:  To evaluate the effect of prostaglandin analogues on the central corneal thickness (CCT) of patients with chronic open‐angle glaucoma (COAG).

New nonlinear multivariable model shows the relationship between central corneal thickness and HRTII topographic parameters in glaucoma patients

Purpose: In this paper a new nonlinear multivariable regression method is presented in order to investigate the relationship between the central corneal thickness (CCT) and the Heidelberg Retina Tomograph (HRTII) optic nerve head (ONH) topographic measurements, in patients with established glaucoma. Methods: Forty nine eyes of 49 patients with glaucoma were included in this study. Inclusion criteria were patients with (a) HRT II ONH imaging of good quality (SD < 30 μm), (b) reliable Humphrey visual field tests (30-2 program), and (c) bilateral CCT measurements with ultrasonic contact pachymetry. Patients were classified as glaucomatous based on visual field and/or ONH damage. The relationship between CCT and topographic parameters was analyzed by using the new nonlinear multivariable regression model. Results: In the entire group, CCT was 549.78 ± 33.08 μm (range: 484–636 μm); intraocular pressure (IOP) was 16.4 ± 2.67 mmHg (range: 11–23 mmHg); MD was −3.80 ± 4.97 dB (range: 4.04 – [−20.4] dB); refraction was −0.78 ± 2.46 D (range: −6.0 D to +3.0 D). The new nonlinear multivariable regression model we used indicated that CCT was significantly related (R2 = 0.227, p < 0.01) with rim volume nasally and type of diagnosis. Conclusions: By using the new nonlinear multivariable regression model, in patients with established glaucoma, our data showed that there is a statistically significant correlation between CCT and HRTII ONH structural measurements, in glaucoma patients.

Multiple spots of photodynamic therapy for the treatment of severe chronic central serous chorioretinopathy

Purpose To evaluate the efficacy and safety of fluorescein angiography (FA)-guided photodynamic therapy (PDT) for the treatment of severe chronic central serous chorioretinopathy (CSC). Methods Patients presenting with chronic CSC with multiple areas of retinal pigment epithelium decompensation, with or without focal leaks, were treated with FA-guided full-fluence PDT. Best-corrected visual acuity (BCVA), optical coherence tomography (OCT), FA, indocyanine green angiography, and fundus autofluorescence were used to determine functional and anatomic outcomes. Results Twenty-one eyes (17 patients) were treated with PDT and followed for a median of 24 months (range, 12–73). In fourteen eyes (66.66%), two PDT spots were performed within the same session. In three eyes (14.28%), three PDT spots were performed, in two eyes (9.52%) four spots, and in two eyes (9.52%) five spots. In 17 eyes (80.95%), the leakage in FA and the subretinal fluid in OCT disappeared after only one session of PDT. In four eyes (19.05%), a second session – with only one spot – of PDT was required due to persistent or recurrent leakage and subfoveal SRF. Median BCVA improved significantly from 20/63 at baseline to 20/40 at 3 months (P = 0.0002) and 20/32 at 6 months (P < 0.0001), and remained improved until the last examination (20/25, P < 0.0001). Two patients complained of a transient central scotoma after the treatment. Conclusion FA-guided full-fluence PDT with multiple PDT spots within the same session seems to be effective and safe for the treatment of chronic CSC cases with multiple areas of retinal pigment epithelium decompensation.

Different Types of Conjunctival Papilloma Presenting in the Same Eye

A 31-year-old Black man presented with two oval masses in his right conjunctiva. The tumors were completely excised and histology showed that the inferior lesion was a conjunctival squamous papilloma with pigmentation while the superior one was an inverted conjunctival papilloma, which grew in an endophytic manner. Follow up examination one year later showed no recurrence. Literature search revealed no previous report of simultaneous appearance of these types of papilloma in the same eye. Management of conjunctival squamous papillomas is difficult and is complicated by multiple recurrences in contrast to inverted conjunctival papillomas where no recurrences have been reported after complete excision. Thus, histopathology is an absolute necessity even when papillomas appear in the same eye.

Nd: YAG capsulotomy for posterior capsule opacification after combined clear corneal phacoemulsification and vitrectomy

Purpose: To evaluate the efficacy and safety of Neodymium:YAG (Nd:YAG) laser capsulotomy for posterior capsule opacification (PCO) following combined phacoemulsification and vitrectomy for the treatment of cataract in association with macular hole (MH) or epiretinal membrane (ERM). Methods: Retrospective clinical study of 34 eyes of 34 patients who underwent combined cataract surgery and vitrectomy, developed PCO, and subsequently underwent Nd:YAG laser capsulotomy. Follow-up examinations included visual acuity measurement, evaluation of intraocular lens (IOL) centration, intraocular pressure (IOP) measurement, and dilated fundus examination. Results: Nd:YAG laser capsulotomy was performed in all 34 eyes. The mean age of the patients was 65.08 years (range 45–87) and the mean follow up period was 11.05 months (range 4–23). The mean time elapsed between the last intraocular operation and the development of PCO was 10.00 months for patients with previous ERM and 15.33 for those with MH (P = 0.001, t-test for equality of means). None of our patients developed recurrence of MH, retinal detachment, IOL dislocation, or permanent IOP elevation. Conclusion: In our study, the most remarkable observation is that no complication occurred after the YAG capsulotomy, possibly because the eyes were vitrectomized and vitreous seems to play an important role in the occurrence of post-Nd:YAG complications. In addition we noted that PCO seems to occur earlier in the eyes undergoing combined surgery for cataract and ERM when compared with those where combined phacoemulsification and vitrectomy are performed for cataract and MH.

Evolution of retinitis sclopetaria after blunt trauma

A 33-year-old man presented after striking his right eye with a champagne cork. His visual acuity was ‘hand movements’ and intraocular pressure of 4 mmHg. Anterior chamber was normal apart from microhyphema; the lens was clear with no signs of subluxation. Fundoscopy was difficult to perform because of diffuse vitreous haemorrhage. Indirect ophthalmoscopy, however, disclosed a superotemporal ‘avulsion’ of choroid and retina with subretinal-choroidal haemorrhage (Fig. 1a). CT scan excluded globe rupture but showed an ‘avulsed’ tissue separating from the intact sclera (Fig. 2). Ultrasound examination showed no signs of retinal detachment. Conservative management was undertaken at the time. During the following 2 months, the vitreous haemorrhage cleared; the subretinal-choroidal blood gradually resolved and the retina and choroid adhered to the underling sclera (Fig. 1b). A fibroglial scar was formed in the margin between bare sclera and choroid/retina. However, chorioretinal folds were evident centrally to the chorioretinal defect (Figs 1b,c,3). Eight months later, fundal examination was unchanged and visual acuity 6/36 (Fig. 4). The term sclopetaria was first used in 1901; it is believed to derive either from the latin word ‘sclopetum’ that refers to a Roman handgun or from the English verb ‘sclow’ that means scratch or tear Retinitis sclopetaria is a rare manifestation of ocular trauma with the largest published series of only 13 cases. It is a rare condition that is traditionally associated with high velocity objects that pass adjacent to, but do not penetrate the globe. The injury of retinitis sclopetaria usually consists of a full thickness defect in the choroid, Bruchs’s membrane and retina adjacent to the path of missile; the latter is accompanied by retraction of this tissue to expose bare sclera. The macula is involved in most of these patients and final visual acuity is usually poor. Bottle cork injury to the eye can cause serious damage, as a blunt object with a diameter smaller that the rim of the orbit hits the eye and the full impact of the shock wave is absorbed by the globe. We postulate that in our patient the rigorous contusion injury caused by the high velocity and force of the champagne cork was followed by severe anteroposterior compression with subsequent equatorial expansion of the globe, resulting in not only choroidal and retinal rupture but also ‘avulsion’ of the choroid and retina from the sclera and subretinal-choroidal haemorrhage (Figs 1a,2). Chorioretinal folds may have developed secondarily, as the result of gravity on the relatively redundant ‘avulsed’ chorioretinal tissue and the resolution of subretinal-choroidal haemorrhage (Fig. 1b,c). In spite of the severity of the trauma, retinal detachment did not occur in our patient and this is in accordance with other published reports concerning retinitis sclopetaria. This could be possibly attributed to the proliferation of fibrous tissue that caused the firm adherence of the retina and the choroid to the sclera (Fig. 1b,c). In concussion, retinal and choroidal avulsion, which to the best of our knowledge has never been reported before, may rarely occur after severe blunt injury. Because of its rarity, it may represent a diagnostic challenge to the oph-