EVALUATION OF MICROBIAL GROWTH ON SINGLE-USE VITRECTOMY PROBES REPROCESSED IN HEALTHCARE PRACTICE

The aim of this study was to evaluate the microbial growth on single-use vitrectomy probes reprocessed in healthcare practice. We investigated nine vitrectomy probes that had been reused and reprocessed using different methods. The samples were sectioned, individually, in portions of 3.5 cm, totaling 979 sampling units (extensions, connectors and vitrectomy cutters), which were inoculated in culture medium and incubated at 37 C for 14 days. The results showed microbial growth on 57 (5.8%) sample units, 25 of which had been sterilized using ethylene oxide, 16 by hydrogen peroxide plasma, and 16 by low-temperature steam and formaldehyde. Seventeen microbial species were identified. The most prevalent were: Micrococcus spp., coagulase-negative Staphylococcus, Pseudomonas spp., and Bacillus subtilis. The reuse of single-use vitrectomy probes was shown to be unsafe, therefore this practice is not recommended.

Corneal wavefront-guided photorefractive keratectomy with mitomycin-C for hyperopia after radial keratotomy: Two-year follow-up

PURPOSE: To assess corneal wavefront-guided photorefractive keratectomy (PRK) to correct hyperopia after radial keratotomy (RK). SETTING: Sadalla Amin Ghanem Eye Hospital, Joinville, Santa Catarina, Brazil. DESIGN: Case series. METHODS: Excimer laser corneal wavefront-guided PRK with intraoperative mitomycin-C (MMC) 0.02% was performed. Main outcome measures were uncorrected (UDVA) and corrected (CDVA) distance visual acuities, spherical equivalent (SE), corneal aberrations, and haze. RESULTS: The mean time between RK and PRK in the 61 eyes (39 patients) was 18.8 years +/- 3.8 (SD). Before PRK, the mean SE was +4.17 +/- 1.97 diopters (D); the mean astigmatism, -1.39 +/- 1.04 D; and the mean CDVA, 0.161 +/- 0.137 logMAR. At 24 months, the mean values were 0.14 +/- 0.99 D (P<.001), -1.19 +/- 1.02 D (P=.627), and 0.072 +/- 0.094 logMAR (P<.001), respectively; the mean UDVA was 0.265 +/- 0.196 (P<.001). The UDVA was 20/25 or better in 37.7% of eyes and 20/40 or better in 68.9%. The CDVA improved by 1 or more lines in 62.3% of eyes. Two eyes (3.3%) lost 2 or more lines, 1 due to corneal ectasia. Thirty eyes (49.2%) were within +/- 0.50 D of intended SE and 45 (73.8%) were within +/- 1.00 D. From 6 to 24 months, the mean SE regression was +0.39 D (P<.05). A significant decrease in coma, trefoil, and spherical aberration occurred. Three eyes developed peripheral haze more than grade 1. CONCLUSION: Corneal wavefront-guided PRK with MMC for hyperopia after RK significantly improved UDVA, CDVA, and higher-order corneal aberrations with a low incidence of visually significant corneal haze.

A study of pent-up demand in ophthalmology: Divinolandia Hospital/Unicamp

Objective: To assess the waiting time for eye care identifying the number of patients with each complaint; to investigate how the waiting time may worsen the patient's condition; to check the screening of urgent cases for effectiveness; and to devise means of increasing the medical-surgical care capacity. Methods: A retrospective descriptive survey was conducted using data obtained on 12 occasions during collaborative team visits to provide eyecare services. These initiatives were designed to decrease the waiting time and to treat urgent cases that occurred on each occasion; eyecare services were provided every Saturday, in the period from June to August 2006, in 16 cities of the region covered by Conderg (Consortium for the Development of the Sao Joao da Boa Vista Administrative Region). Results: Referrals used 1,743 (87.1%) of the 2,000 places available. The most frequent diagnoses were refractive errors, with 683 cases, corresponding to 39.1% of the total, followed by cataracts, with 296 cases, corresponding to 20.9%. Of the 238 surgeries indicated, 54.6% were phakectomies. Thirty-five (2.0%) cases were considered urgent. Conclusion: The most common diagnoses made during the team visits to manage the excess demand for eyecare were refractive errors and cataracts, which, together, accounted for the majority of the cases. The Divinolandia Hospital has the necessary human and material resources to meet the demand left unattended by the local SUS network. Immediate referral of urgent cases by the primary units' screeners proved effective.

Rescue technique for salvaging toric intraocular lens alignment

Accurate alignment of a toric intraocular lens (IOL) is a requisite to achieving the intended reduction in astigmatism at the time of cataract surgery. However, it requires a reasonably clear view of the limbal vascular anatomy, which is sometimes altered by chemosis from a subconjunctival anesthetic injection or a hemorrhage. We describe a technique that can quickly restore vascular anatomy and facilitate toric IOL alignment.

Sulcus anatomy and diameter in pseudophakic eyes and correlation with biometric data: Evaluation with a 50 MHz ultrasound biomicroscope

PURPOSE: To evaluate the sulcus anatomy and possible correlations between sulcus diameter and white-to-white (WTW) diameter in pseudophakic eyes, data that may be important in the stability of add-on intraocular lenses (IOLs). SETTING: University Eye Hospital, Tuebingen, Germany. DESIGN: Case series. METHODS: In pseudophakic eyes, the axial length (AL) and horizontal WTW were measured by the IOLMaster device. Cross-sectional images were obtained with a 50 MHz ultrasound biomicroscope on the 4 meridians: vertical, horizontal (180 degrees), temporal oblique, and nasal oblique. Sulcus-to-sulcus (STS), angle-to-angle (ATA), and sclera-to-sclera (ScTSc) diameters were measured. The IOL optic diameter (6.0 mm) served as a control. To test reliability, optic measurements were repeated 5 times in a subset of eyes. RESULTS: The vertical ATA and STS diameters were statistically significantly larger than the horizontal diameter (P=.0328 and P=.0216, respectively). There was no statistically significant difference in ScTSc diameters. A weak correlation was found between WTW and horizontal ATA (r = 0.5766, P<.0001) and between WTW and horizontal STS (r = 0.5040, P=.0002). No correlation was found between WTW and horizontal ScTSc (r = 0.2217, P=.1217). CONCLUSIONS: The sulcus anatomy had a vertical oval shape with the vertical meridian being the largest, but it also had variation in the direction of the largest meridian. The WTW measurements showed a weak correlation with STS. In pseudophakic eyes, Soemmerring ring or a bulky haptic may affect the ciliary sulcus anatomy.

Capsulorhexis rescue after peripheral radial tear-out: Quick-pull technique

We describe a technique to rescue the continuous curvilinear capsulorhexis (CCC) in cases in which complete radial tears make it impossible to use normal traction forceps. A circumferential path and rapid movement are applied in the plane of the anterior capsule in the direction of the center pupil. This technique was used in 50 cases. In 47, the CCC could be completed; in 3, it could not and surgery was continued with low-parameter phacoemulsification. No other intraoperative complications occurred.

Effect of aspherical and yellow tinted intraocular lens on blue-on-yellow perimetry

PURPOSE: To investigate the possible effect of aspherical or yellow tinted intraocular lens (IOL) on contrast sensitivity and blue-on-yellow perimetry. METHODS: This prospective randomized bilateral double-masked clinical study included 52 patients with visually significant bilateral cataracts divided in two groups; 25 patients (50 eyes) received aspherical intraocular lens in one eye and spherical intraocular lens in the fellow eye; and 27 patients (54 eyes) received ultraviolet and blue light filter (yellow tinted) IOL implantation in one eye and acrylic ultraviolet filter IOL in the fellow eye. The primary outcome measures were contrast sensitivity and blue-on-yellow perimetry values (mean deviation [MD] and pattern standard deviation [PSD]) investigated two years after surgery. The results were compared intra-individually. RESULTS: There was a statistically significant between-group (aspherical and spherical intraocular lens) difference in contrast sensitivity under photopic conditions at 12 cycles per degree and under mesopic conditions at all spatial frequencies. There were no between-group significant differences (yellow tinted and clear intraocular lens) under photopic or mesopic conditions. There was no statistically significant difference between all intraocular lens in MD or PSD. CONCLUSION: Contrast sensitivity was better under mesopic conditions with aspherical intraocular lens. Blue-on-yellow perimetry did not appear to be affected by aspherical or yellow tinted intraocular lens. Further studies with a larger sample should be carried out to confirm or not that hypotheses.

Cancelamento de cirurgias de catarata em um hospital público de referência

OBJETIVO: Analisar a incidência e causas de cancelamento de cirurgias de catarata em um hospital público de referência. MÉTODOS: Trata-se de um estudo retrospectivo em que foram analisados o número de cancelamentos de facectomias durante o ano de 2009. Foram analisados sexo, idade, tipo de procedimento suspenso (facoemulsificação ou extração extracapsular do cristalino), tipo de anestesia, convênio (Sistema Único de Saúde ou convênio/particular) e motivo de suspensão da cirurgia (causas clínicas, institucionais ou pessoais). RESULTADOS: Foram agendadas no período 2.965 cirurgias de catarata, havendo 650 cancelamentos (21,92%). Dentre as principais razões para a suspensão do procedimento destacaram-se as causas clínicas (86,90%). Os meses de inverno apresentaram os maiores índices de suspensão de cirurgias de catarata. CONCLUSÃO: A taxa de cancelamento de cirurgia de catarata em serviços públicos parece ser a mesma que há 10 anos. A principal causa de suspensão deve-se por condições clínicas (hipertensão, diabetes, falta de exames, etc.).

Facoemulsificação versus extração extracapsular no sistema público de saúde: análise de custos para o hospital, para o governo e para a sociedade

OBJETIVO: Comparar custos da cirurgia de catarata em larga escala para um hospital público, para o governo e para a sociedade, pelas técnicas de facoemulsificação (FACO) e extração extracapsular (EECP). MÉTODOS: Foi realizada revisão baseada principalmente em diversos estudos clínicos realizados entre 2002 e 2010, no Centro Cirúrgico Ambulatorial do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. RESULTADOS: Os gastos estimados com os insumos utilizados para as cirurgias foram de R$ 468,92 no grupo FACO e R$ 259,96 no grupo EECP. As despesas hospitalares com o acompanhamento pós-operatório foram em média de R$ 16,40 (42%) menores no grupo FACO. Com relação ao gasto estimado para a Previdência Social, o grupo EECP custou em média, US$ 44,58 por paciente a mais que o grupo FACO. CONCLUSÃO: O incentivo e o investimento governamental para a realização da FACO no SUS são socialmente justificados, deve-se considerar também a economia dos pacientes e do sistema empresarial, bem como as vantagens clínicas para os pacientes e vantagens econômicas para os hospitais.

A clinical comparison between DisCoVisc and 2% hydroxypropylmethylcellulose in phacoemulsification: a fellow eye study

OBJECTIVE: This study sought to compare the effects and outcomes of two ophthalmic viscosurgical devices, 1.6% hyaluronic acid/4.0% chondroitin sulfate and 2.0% hydroxypropylmethylcellulose, during phacoemulsification. METHODS: This prospective, randomized clinical trial comprised 78 eyes (39 patients) that received phacoemulsification performed by the same surgeon using a standardized technique. Patients were randomly assigned to receive either 1.6% hyaluronic acid/4.0% chondroitin sulfate or 2.0% hydroxypropylmethylcellulose on the first eye. The other eye was treated later and received the other viscoelastic agent. Preoperative and postoperative examinations (5, 24 and 48 hours; 7 and 14 days; 3 and 6 months) included measurements of the total volume of the ophthalmic viscosurgical device, ultrasound and washout times to completely remove the ophthalmic viscosurgical device, intraocular pressure, central corneal thickness and best-corrected visual acuity. The corneal endothelial cell count was measured at baseline and at six months postoperatively. ClinicalTrials.gov: NCT01387620. RESULTS: There were no statistically significant differences between groups in terms of cataract density or ultrasound time. However, it took longer to remove 2.0% hydroxypropylmethylcellulose than 1.6% hyaluronic acid/ 4.0% chondroitin sulfate, and the amount of viscoelastic material used was greater in the 2.0% hydroxypropylmethylcellulose group. In addition, the best-corrected visual acuity was significantly better in the hyaluronic acid/ chondroitin sulfate group, but this preferable outcome was only observed at 24 hours after the operation. There were no statistically significant differences between the two ophthalmic viscosurgical devices regarding the central corneal thickness or intraocular pressure measurements at any point in time. The corneal endothelial cell count was significantly higher in the hyaluronic acid/chondroitin sulfate group. CONCLUSION: The ophthalmic viscosurgical device consisting of 1.6% hyaluronic acid/4.0% chondroitin sulfate was more efficient during phacoemulsification and was easier to remove after IOL implantation than 2.0% hydroxypropylmethylcellulose. In addition, the corneal endothelial cell count was significantly higher following the use of hyaluronic acid/chondroitin sulfate than with hydroxypropylmethylcellulose, which promoted an improved level of corneal endothelium protection.

Pathogenic mechanisms in mitochondrial optic neuropathies

Leber’s hereditary optic neuropathy (LHON) and Autosomal Dominant Optic Atrophy (ADOA) are the two most common inherited optic neuropathies and both are the result of mitochondrial dysfunctions. Despite the primary mutations causing these disorders are different, being an mtDNA mutation in subunits of complex I in LHON and defects in the nuclear gene encoding the mitochondrial protein OPA1 in ADOA, both pathologies share some peculiar features, such a variable penetrance and tissue-specificity of the pathological processes. Probably, one of the most interesting and unclear aspect of LHON is the variable penetrance. This phenomenon is common in LHON families, most of them being homoplasmic mutant. Inter-family variability of penetrance may be caused by nuclear or mitochondrial ‘secondary’ genetic determinants or other predisposing triggering factors. We identified a compensatory mechanism in LHON patients, able to distinguish affected individuals from unaffected mutation carriers. In fact, carrier individuals resulted more efficient than affected subjects in increasing the mitochondrial biogenesis to compensate for the energetic defect. Thus, the activation of the mitochondrial biogenesis may be a crucial factor in modulating penetrance, determining the fate of subjects harbouring LHON mutations. Furthermore, mtDNA content can be used as a molecular biomarker which, for the first time, clearly differentiates LHON affected from LHON carrier individuals, providing a valid mechanism that may be exploited for development of therapeutic strategies. Although the mitochondrial biogenesis gained a relevant role in LHON pathogenesis, we failed to identify a genetic modifying factor for the variable penetrance in a set of candidate genes involved in the regulation of this process. A more systematic high-throughput approach will be necessary to select the genetic variants responsible for the different efficiency in activating mitochondrial biogenesis. A genetic modifying factor was instead identified in the MnSOD gene. The SNP Ala16Val in this gene seems to modulate LHON penetrance, since the Ala allele in this position significantly predisposes to be affected. Thus, we propose that high MnSOD activity in mitochondria of LHON subjects may produce an overload of H2O2 for the antioxidant machinery, leading to release from mitochondria of this radical and promoting a severe cell damage and death ADOA is due to mutation in the OPA1 gene in the large majority of cases. The causative nuclear defects in the remaining families with DOA have not been identified yet, but a small number of families have been mapped to other chromosomal loci (OPA3, OPA4, OPA5, OPA7, OPA8). Recently, a form of DOA and premature cataract (ADOAC) has been associated to pathogenic mutations of the OPA3 gene, encoding a mitochondrial protein. In the last year OPA3 has been investigated by two different groups, but a clear function for this protein and the pathogenic mechanism leading to ADOAC are still unclear. Our study on OPA3 provides new information about the pattern of expression of the two isoforms OPA3V1 and OPA3V2, and, moreover, suggests that OPA3 may have a different function in mitochondria from OPA1, the major site for ADOA mutations. In fact, based on our results, we propose that OPA3 is not involved in the mitochondrial fusion process, but, on the contrary, it may regulate mitochondrial fission. Furthermore, at difference from OPA1, we excluded a role for OPA3 in mtDNA maintenance and we failed to identify a direct interaction between OPA3 and OPA1. Considering the results from overexpression and silencing of OPA3, we can conclude that the overexpression has more drastic consequences on the cells than silencing, suggesting that OPA3 may cause optic atrophy via a gain-of-function mechanism. These data provide a new starting point for future investigations aimed at identifying the exact function of OPA3 and the pathogenic mechanism causing ADOAC.

Studio caso-controllo multicentrico su distacco di retina e movimentazione manuale di carichi

Obiettivo Valutare l’ipotesi secondo cui la movimentazione manuale di carichi possa essere un fattore di rischio per il di distacco di retina. Metodi Si è condotto uno studio caso-controllo ospedaliero multicentrico, a Bologna, (reparto di Oculistica del policlinico S. Orsola Malpighi, Prof. Campos), e a Brescia (reparto di oculistica “Spedali Civili” Prof. Semeraro). I casi sono 104 pazienti operati per distacco di retina. I controlli sono 173 pazienti reclutati tra l’utenza degli ambulatori del medesimo reparto di provenienza dei casi. Sia i casi che i controlli (all’oscuro dall’ipotesi in studio) sono stati sottoposti ad un’intervista, attraverso un questionario strutturato concernente caratteristiche individuali, patologie pregresse e fattori di rischio professionali (e non) relativi al distacco di retina. I dati relativi alla movimentazione manuale di carichi sono stati utilizzati per creare un “indice di sollevamento cumulativo―ICS” (peso del carico sollevato x numero di sollevamenti/ora x numero di anni di sollevamento). Sono stati calcolati mediante un modello di regressione logistica unconditional (aggiustato per età e sesso) gli Odds Ratio (OR) relativi all’associazione tra distacco di retina e vari fattori di rischio, tra cui la movimentazione manuale di carichi. Risultati Oltre alla chirurgia oculare e alla miopia (fattori di rischio noti), si evidenzia un trend positivo tra l’aumento dell’ICS e il rischio di distacco della retina. Il rischio maggiore si osserva per la categoria di sollevamento severo (OR 3.6, IC 95%, 1.5–9.0). Conclusione I risultati, mostrano un maggiore rischio di sviluppare distacco di retina per coloro che svolgono attività lavorative che comportino la movimentazione manuale di carichi e, a conferma di quanto riportato in letteratura, anche per i soggetti miopi e per coloro che sono stati sottoposti ad intervento di cataratta. Si rende quindi evidente l’importanza degli interventi di prevenzione in soggetti addetti alla movimentazione manuale di carichi, in particolare se miopi.

Identifizierung und Charakterisierung von Protein-Biomarkern beim Glaukom

Das Glaukom ist, nach dem Katarakt, die zweithäufigste Ursache für Erblindungen weltweit mit Milionen von Betroffenen, die von dieser zunächst weitgehend symptomfreien neurodegenerativen Erkrankung heimgesucht werden. Die Möglichkeiten auf dem Feld der Diagnose beschränken sich bislang weitestgehend auf die Messung des Augeninnendrucks und der Beurteilung des Augenhintergrundes durch einen erfahrenen Augenarzt. Eine labordiagnostische Prophylaxe ist bis heute nicht verfügbar, die Zahl unerkannter Erkrankungen dementsprechend hoch. Hierdurch geht wertvolle Zeit verloren, die man für eine effektive Therapie nutzen könnte.rnBezüglich der Pathogenese des Glaukoms geht man heute von mehreren, miteinander wechselwirkenden Pathomechanismen aus, zu denen neben mechanischen Einflüssen durch einen erhöhten IOD auch Hypoxie, verminderte Neutrophinversorgung, Exzitotoxizität, oxidativer Stress und eine Beteiligung autoimmuner Prozesse gezählt werden. Unabhängig vom Pathomechanismus folgt stets die Etablierung umfangreicher degenerativer Prozesse im Sehnervenkopf, den retinalen Ganglienzellen und den Axonen des Sehnerven, die letztlich im irreversiblen Untergang dieser Neuronen münden. Diese pathologischen Prozesse im ZNS hinterlassen auf Proteomebene Spuren, die mithilfe moderner massenspektrometrischer Methoden in Kombination mit multivariaten statistischen Methoden detektierbar und als sogenannte Biomarker-Kandidaten mit definiertem Molekulargewicht darstellbar sind. In dieser Arbeit wurde ein „Workflow“ entwickelt, der es ermöglicht, diese Biomarker-Kandidaten im Blutserum und in der Tränenflüssigkeit in einfachen, reproduzierbaren Schritten zu identifizieren und zu charakterisieren. Abweichend von der etablierten Methotik der Bottom-Up-Proteomics musste hierfür eine Methode entsprechend einer Top-Down-Philosophie entwickelt werden, die es erlaubt, die Spuren des Glaukoms im Proteom zu detektieren und zu charakterisieren.rnDies erfolgte in dieser Arbeit durch sowohl massenspektroskopischen Methoden wie SELDI-TOF® und MALDI-Tof-Tof als auch durch Bead-, Gel- und Flüssigkeits-chromatographisch-basierte Separations und Fraktionierungstechniken.rnDie erfolgreiche Kombination dieser Methoden führte zu Identifikationen einer ganzen Reihe von Biomarker-Kandidaten. Unter den identifizierten Proteinen, die bezüglich ihres korrespondierenden SELDI-Peaks im Massenbereich von Biomarker-Kandidaten liegen, finden sich Zytokine und Effektormoleküle der angeborernen Immunität, stressinduzierbare Kinasen, Faktoren, die zum Schutz der Telomeren dienen, Proliferationsmarker, neuronale Antigene und Transportproteine. Darüber hinaus wurden Komponenten identifiziert, die an der neuronalen Neutrophinversorgung beteiligt sind, neuronale Rezeptoren und Antigene, Komponenten des Komplementsystems und des MHC-I-Komplexes. All diese identifizierten Proteine sind bezüglich ihrer Funktion und möglichen Rolle innerhalb der Pathogenese des Glaukoms detailliert beschrieben und charakterisiert. Dies erlaubt einen umfassenden Einblick in alle Pathomechanismen, denen nach heutigem Kenntnisstand, eine Rolle an der Pathogenese des Glaukoms unterstellt wird.rn

Simple and objective method for routine detection of the macular pigment xanthophyll

A new simple method for two-dimensional determination of optical density of macular pigment xanthophyll (ODx) in clinical routine is based on a single blue-reflection fundus image. Individual different vignetting is corrected by a shading function. For its construction, nodes are automatically found in structureless image regions. The influence of stray light in elderly crystalline lenses is compensated by a correction function that depends on age. The reproducibility of parameters in a one-wavelength reflection method determined for three subjects (47, 61, and 78 years old) was: maxODx = 6.3%, meanODx = 4.6%, volume = 6%, and area = 6% already before stray-light correction. ODx was comparable in pseudophakic and in an eye with a crystalline lens of the same 11 subjects after stray-light correction. Significant correlation in ODx was found between the one-wavelength reflection method and the two-wavelength autofluorescence method for pseudophakic and cataract eyes of 19 patients suffering from dry age-related macular degeneration (AMD) (R(2) = 0.855). In pseudophakic eyes, maxODx was significantly lower for dry AMD (n = 45) (ODx = 0.491±0.102 ODU) than in eyes with healthy fundus (n = 22) (ODx = 0.615±0.103 ODU) (p = 0.000033). Also in eyes with crystalline lens, maxODx was lower in AMD (n = 125) (ODx = 0.610±0.093 ODU) than in healthy subjects (n = 45) (ODx = 0.674±0.098 ODU) (p = 0.00019). No dependence on age was found in the pseudophakic eyes both of healthy subjects and AMD patients.