Efecto de la acetazolamida en la vasculatura retiniana y coroidea de la mácula y el disco óptico mediante angiografía OCT / The effect of acetazolamide on the retinal and choroidal vasculature of the macula and the optic disc using OCT angiography

Introducción y objetivos Investigar el efecto de la acetazolamida (AZ) sobre la microvasculatura ocular retiniana y coroidea en la mácula y los capilares peripapilares radiales (CPR) del disco óptico con angiografía-OCT (OCTA). Materiales y métodos Estudio transversal observacional de 9meses de duración. Se reclutaron 45 ojos de 45 participantes sanos que se sometieron a cirugía de cataratas. Se comparó la densidad de vasos (DV) de la retina macular y la coriocapilar (CC) y la DV de la CPR en la zona del disco óptico antes y 60 min después de administrar 250mg de AZ por vía oral. También se midieron la presión intraocular (PIO) y la presión arterial (PA) sistémica antes de cada exploración. Resultado La edad media era de 73,1±6,9 años. La densidad de vasos (DV) en el plexo capilar superficial (PCS) y profundo (PCP) de la retina y la CC en el área macular no mostraron cambios significativos (p>0,5, para todos los parámetros). La DV en los CPR no mostró cambios significativos con la AZ (p>0,5, para todos los parámetros). El grosor foveal y parafoveal aumentó de 248,98 (± 23,89) a 250,33 (± 23,74) y de 311,62 (± 16,53) a 311,98 (± 16,38) (p<0,001 y p=0,046), respectivamente. La PIO disminuyó de 13,2 (± 3,0) mmHg a 11,8 (± 3,2) mmHg (p<0,001), mientras que la PA sistólica y diastólica disminuyó de 144,8 (± 21,8) a 137,7 (± 19,0) y de 80,0 (± 12,7) a 76,2 (± 11,7) (p=0,021 y p=0,030), respectivamente. Conclusiones Las imágenes de OCTA no revelaron cambios significativos en la VD del disco óptico ni en el VD de la retina y la coroides en la mácula con AZ oral una hora después de su administración en participantes por lo demás sanos que se sometieron a cirugía de cataratas (AU)

Introduction and objectives To investigate the effect of acetazolamide (AZ) on the retinal and choroidal ocular microvasculature in the macula and radial peripapillary capillaries (RPC) of the optic disc with OCT Angiography (OCTA). Materials and method Nine-month observational cross-sectional study. Forty-five eyes from 45 healthy participants who underwent cataract surgery were recruited. Macular retina and choriocapillaris vessel density (VD) and RPC VD in the optic disc area were compared before and 60minutes after 250mg acetazolamide per os. Intraocular pressure (IOP) and systemic blood pressure (BP) were also measured before each scan. Result Mean age was 73.1±6.9 years. VDs in the superficial (SCP) and deep (DCP) capillary plexus of the retina and the choriocapillaris (CC) in the macular area showed no significant change (p>0.5, for all parameters). VD in the RPC showed no significant change with AZ (p>0.5, for all parameters). Foveal and parafoveal thickness increased from 248.98 (±23.89) to 250.33 (±23.74) and from 311.62 (±16.53) to 311.98 (±16.38) (p<0.001 and p=0.046), respectively. IOP decreased from 13.2 (±3.0) mmHg to 11.8 (±3.2) mmHg (p<0.001), while systolic and diastolic BP decreased from 144.8 (±21.8) to 137.7 (±19.0) and from 80.0 (±12.7) to 76.2 (±11.7) (p=0.021 and p=0.030), respectively. Conclusion OCTA imaging did not reveal any significant changes in the VD of the optic disc or the retinal and choroidal VD in the macula with oral AZ one hour after its administration in otherwise healthy participants who underwent cataract surgery (AU)

The effect of acetazolamide on the retinal and choroidal vasculature of the macula and the optic disc using OCT angiography.

INTRODUCTION AND OBJECTIVES: To investigate the effect of acetazolamide (AZ) on the retinal and choroidal ocular microvasculature in the macula and radial peripapillary capillaries (RPC) of the optic disc with OCT Angiography (OCTA). MATERIALS AND METHODS: Nine-month observational cross-sectional study. Forty-five eyes from 45 healthy participants who underwent cataract surgery were recruited. Macular retina and choriocapillaris vessel density (VD) and RPC VD in the optic disc area were compared before and 60min after 250mg acetazolamide per os. Intraocular pressure (IOP) and systemic blood pressure (BP) were also measured before each scan. RESULTS: Mean age was 73.1±6.9 years. VDs in the superficial (SCP) and deep (DCP) capillary plexus of the retina and the choriocapillaris (CC) in the macular area showed no significant change (P>.5, for all parameters). VD in the RPC showed no significant change with AZ (P>.5, for all parameters). Foveal and parafoveal thickness increased from 248.98 (±23.89) to 250.33 (±23.74) and from 311.62 (±16.53) to 311.98 (±16.38) (P<.001 and P=.046), respectively. IOP decreased from 13.2 (±3.0) mmHg to 11.8 (±3.2) mmHg (P<.001), while systolic and diastolic BP decreased from 144.8 (±21.8) to 137.7 (±19.0) and from 80.0 (±12.7) to 76.2 (±11.7) (P=.021 and P=.030), respectively. CONCLUSIONS: OCTA imaging did not reveal any significant changes in the VD of the optic disc or the retinal and choroidal VD in the macula with oral AZ one hour after its administration in otherwise healthy participants who underwent cataract surgery.

[Cross-linking in an artificial human cornea via induction of tissue transglutaminases]. / Vernetzung einer humanen künstlichen Hornhaut durch Induktion von Tissue-Transglutaminasen.

PURPOSE: In recent years many three-dimensional cornea models have been developed. However, they show poor collagen stability in the stroma. Transglutaminases (Tgases) are calcium-dependent proteins which play an important role in cross-linking of the corneal stroma. The purpose of this study was to find out whether it is possible to induce in vitro cross-linking of the stroma in an artificial hemicornea model with the help of Tgases. MATERIALS AND METHODS: For the construction of the hemicornea, human SV40 adenovector corneal epithelial cells (HCE) and human SV40 adenovector corneal keratocytes (HCK) were cultivated. Confluent HCK cells were treated for 24 h with transforming growth factor beta (TGFb) 1, 2 and 3 at different concentrations as well as with other growth factors and the treated cells were compared to untreated cultivated cells. The quantification of the expression of the Tgases by HCKs was examined with the use of real time PCR, Western blot imaging and immunochemistry. RESULTS: All concentrations of TGFbs used resulted in a significant increase of Tgase-mRNA, Tgase protein level and Tgase activity. The Tgases remained unaffected after treatment with other growth factors in comparison to untreated control cells. Treatment of the hemicornea with TGFb2 showed a very strong contraction and haze in comparison to the untreated hemicornea. CONCLUSION: It has been shown for the first time that TGFb induces a strong expression of Tgases in HCK cells. This effect caused an undesired contraction and haze of the human hemicornea model. Further research is necessary in order to find out whether the induction of Tgases in the HCK cells can be regulated without losing stability of the constructed hemicornea.

Repeatability and reproducibility of a-scan biometry quantitative findings.

PURPOSE: To determine repeatability and reproducibility of A-scan biometry quantitative findings in order to uniformly evaluate lenticular cataract changes. MATERIALS AND METHODS: Seventeen eyes from seventeen cataract patients were examined by three (trainee ophthalmologists). Results (ratio of mean internal lens spikes height/lens anterior surface spike height) were compared using coefficient of variation (CV), repeatability coefficient (CR), and intraclass correlation coefficients (ICC). RESULTS: Intra-observer consistency was CV = 0.36, CR = 0.49, and ICC = 0.778 for the first operator; CV = 0.33, CR = 0.52, and ICC = 0.642 for the second operator; and CV = 0.32, CR = 0.53, and ICC = 0.567 for the third operator. Concerning inter-observer agreement: CV (in 6 of 7 eyes) was > 8%, CR was > 0.21, and intraclass correlation coefficient for all eyes was < 0.81. CONCLUSIONS: Regarding repeatability and reproducibility, although there is a tendency for statistical significance, variability of the results does not allow the use of the method as a complementary clinical tool for comparing results. Standardization of this procedure, in order to achieve higher test reliability, might be the aim of relevant future studies, although there are a number of points that have to be addressed.

[Postoperative deposits on a second-generation silicone lens]. / Postoperative Eintrübungen einer Silikonlinse zweiter Generation.

BACKGROUND: In the literature there have often been reports about deposits (hydroxyapatite) in hydrophilic or hydrophobic intraocular lenses (IOLs). We report, for the first time, about deposits on a silicone IOL of the second generation. MATERIALS AND METHODS: A silicone IOL (Allergan, type SI-40) which was extracted due to gradual visual loss, has been examined. RESULTS: The examination with the scanning electron microscope (SEM) showed crystalline precipitations in the anterior surface of the IOL while the X-ray analysis showed the existence of calcium and carbon, whereas no phosphorus was found. CONCLUSIONS: It could be hypothesised that metabolic disorders in aqueous humor (i. e., in patients with diabetes mellitus), the quality of the production of the lens, and not the IOL material, are the main cause for deposits in the IOL surface.

A comparison of endophthalmitis after phacoemulsification or extracapsular cataract extraction in a socio-economically deprived environment: a retrospective analysis of 2446 patients.

PURPOSE: To assess which cataract operation technique involves least risk of postoperative endophthalmitis, when performed in a population living in poor hygiene conditions. METHODS: This retrospective clinical study evaluated 2446 cases at the Eye Clinic of the Komotini General Hospital, Greece, between January 1998 and January 2001. RESULTS: Endophthalmitis arose in 12/1055 patients (1.13%) after extracapsular cataract extraction (ECCE) and in 8/1391 after phacoemulsification (0.57%). The mean time to onset of endophthalmitis was 23 and 73 days respectively after phacoemulsification and ECCE. This difference was statistically significant. CONCLUSIONS: Endophthalmitis develops considerably later after ECCE than phacoemulsification. Thus it would appear that hygiene conditions have a stronger effect in patients operated with the ECCE technique. In order to reduce the risk of endophthalmitis after cataract extraction in patients living in substandard conditions, phacoemulsification is proposed as preferable to ECCE.

Retinoblastoma with an unusual presentation in a child with polydactyly. Clinical associations and genetic implications.

Retinoblastoma is the most common intraocular malignancy of childhood. It may rarely present with white spots on the iris and pseudohypopyon. We report a case of an 11-month old child with polydactyly with this presentation of retinoblastoma. There was no positive family history of the disease. Investigations included anterior segment examination under anaesthesia, fundoscopy with scleral indentation, A- and B-scan ultrasound and MRI examination of the head. This was a Reese Ellsworth group 5 retinoblastoma with an indication for enucleation. Pathology reports of the enucleated globe showed choroidal and ciliary body invasion. Therefore, subsequent chemotherapy treatment was undertaken. The retinoblastoma gene is located in the long arm of chromosome 13. Almost all familial and bilateral cases carry the abnormal gene. In unilateral isolated retinoblastomas--as in our case--most patients do not have a germinal mutation, however, only DNA analysis can safely exclude that. We also discuss possible factors having a link to both polydactyly and retinoblastoma.

Role of electroretinography in the assessment of retinal function as an indicator of vitamin A status.

Hypovitaminosis A is associated with exocrine pancreatic insufficiency in cystic fibrosis. Peripheral retinal dysfunction is an early finding of vitamin A deficiency. We evaluated serum retinol and zinc as well as visual adaptation in 41 patients with cystic fibrosis, receiving generous pancreatic enzyme and micronutrient supplementation. Forty-one normal individuals matched for age and sex served as controls. Peripheral retinal function was measured by clinical electroretinography using an Electrophysiologic Personal Interfaced Computer and applying a standard protocol. Serum retinol in cystic fibrosis was significantly lower than that of the control group (0.30+/-0.01 versus 0.39+/-0.02 mg/l, p<0.001). Serum zinc concentrations were normal in the cystic fibrosis group (1.21+/-0.03 mg/l) and significantly higher than that of the control group (1.02+/-0.01 mg/l, p<0.001). The overall visual adaptation, however, was found to be normal and comparable in the two groups. It is concluded that, in cystic fibrosis, despite appropriate vitamin A supplementation, retinol serum concentration may be low. As serum retinol does not reflect vitamin A status, evaluation of visual adaptation may be a more appropriate way to monitor for vitamin A deficiency in cystic fibrosis.

Ultrasonographic classification and phacoemulsification of white senile cataracts.

OBJECTIVE: To classify the white senile cataracts and report the results of phacoemulsification of white cataracts. DESIGN: Prospective, noncomparative case series. PARTICIPANTS: One hundred eyes were included. INTERVENTION: White cataracts were examined biomicroscopically before surgery, and their acoustic structure was analyzed with standardized A-scan echography. White cataract surgery was performed with phacoemulsification via a superior temporal near-limbus corneal approach using a bimanual divide-and-conquer or stop-and-chop technique. Patients were followed after surgery for a period of 9 months. MAIN OUTCOMES MEASURES: The A-scan acoustic structure of white cataracts; successful accomplishment of capsulorrhexis; mean phacoemulsification time, power, and energy; intraoperative and postoperative complications of phacoemulsification; and visual acuity at 9 months after surgery. RESULTS: White senile cataracts were categorized into three different types. Type I included intumescent, white cataracts with cortex liquefaction and high internal acoustic reflections (44 eyes), type II included white cataracts with voluminous nuclei, little amount of whitish solid cortex, and low internal acoustic reflections (49 eyes), and type III included white cataracts with fibrosed anterior capsule and low internal echospikes (7 eyes). Circular capsulorrhexis was completed in 79 eyes and was significantly less successful in eyes with type I intumescent, white cataracts compared with type II white cataracts (P = 0.0034). Mean phacoemulsification time and energy were higher in type II and type III white cataracts. Posterior capsule rupture occurred in ten eyes, and three of these eyes were complicated by vitreous loss. In 95 eyes, the posterior chamber lens was implanted in the capsular bag and in five eyes in the sulcus. After surgery, a transient corneal edema developed in 31 eyes. At the final 6-month examination, the mean postoperative visual acuity was 20/30. CONCLUSION: Current phacoemulsification techniques can safely manage eyes with senile white cataracts. The increased risk of difficulty with continuous capsulorrhexis in type-I and type-III white cataracts and the substantial nuclear hardness in type-II and mainly type-III white cataracts would suggest that current phacoemulsification techniques might not be as successful in these patients as they are in ordinary earlier cataracts.

Primary vitrectomy with perfluoro-n-octane use in the treatment of pseudophakic retinal detachment with undetected retinal breaks.

PURPOSE: This report describes the results of a prospective trial to evaluate the efficacy of pars plana vitrectomy (PPV) in conjunction with perfluoro-n-octane (PFO) as initial treatment of pseudophakic retinal detachment (RD) with no breaks diagnosed preoperatively. METHODS: Fourteen consecutive eyes presenting with pseudophakic RD in which retinal breaks could not be identified preoperatively underwent primary PPV, internal microsurgical identification of the retinal breaks with endoillumination and noncontact wide angle viewing system, PFO retinal reattachment, transscleral cryopexy or endolaser treatment of breaks, PFO-air exchange, and final injection of 20% sulfur hexafluoride. In five eyes, a scleral buckle was also used. Mean follow-up period was 18 months. RESULTS: In 13 of the 14 eyes in which no breaks had been identified preoperatively, breaks were diagnosed during surgery. Perfluoro-n-octane retinal attachment facilitated accurate microscopic treatment of retinal breaks. The retina was reattached with a single operation in all eyes. Eleven eyes had final visual acuity of 20/60 or better. Complications were minimal. CONCLUSIONS: Pars plana vitrectomy in conjunction with PFO expression of subretinal fluid is effective in the initial treatment of pseudophakic RD with no preoperative diagnosis of retinal breaks.