Urs Vossmerbaeumer

Original articleThe Impact on Vision of Aspheric to Spherical Monofocal Intraocular Lenses in Cataract Surgery: A Systematic Review with Meta-analysis

PURPOSEnTo provide a summary of the impact on vision of an aspheric intraocular lens (IOL) compared with a spherical IOL in cataract surgery.nnnDESIGNnSystematic review with meta-analysis.nnnPARTICIPANTSnPatients from published randomized controlled trials (RCTs) of cataract surgery with aspheric compared with spherical monofocal IOL implantation.nnnMETHODSnWe systematically searched the peer-reviewed literature in MEDLINE, EMBASE, Web of Science, BIOSIS, and the Cochrane Library according to the Cochrane Collaboration method to identify relevant RCTs. The inclusion criteria were RCTs on cataract surgery comparing the use of aspheric versus spherical IOL implantation that assessed visual acuity, contrast sensitivity, or quality of vision. The effects were calculated as mean differences or standardized mean differences (Hedges g) and pooled using random-effect models.nnnMAIN OUTCOME MEASURESnBest-corrected visual acuity (BCVA), contrast sensitivity, and subjective perception of the quality of vision.nnnRESULTSnForty-three studies provided data and were included, comprising 2076 eyes implanted with aspheric IOLs and 2034 eyes implanted with spherical IOLs. The BCVA showed a significant difference for aspheric IOLs (-0.01 logarithm of the minimum angle of resolution; 95% confidence interval [CI], -0.02 to -0.00). For contrast sensitivity, a significant advantage for aspheric IOLs was found under photopic and mesopic light conditions (photopic: Hedges g 0.42, 95% CI 0.24-0.61 (3 cycles per degree [cpd]) to 0.53, 95% CI 0.33-0.73 (12 cpd); mesopic: Hedges g 0.49, 95% CI 0.23-0.75 (1.5 cpd) to 0.76, 95% CI 0.52-1.00 (18 cpd)). Questionnaires targeting the subjective perception of quality of vision yielded less conclusive results.nnnCONCLUSIONSnOverall, a patient may achieve better contrast sensitivity with an aspheric IOL than with a spherical IOL, especially under dim light. There was no clinically relevant difference in BCVA between aspheric and spherical IOL implantation. The findings on the subjective perception of visual quality were heterogeneous with no clear result favoring either option.

Irregularity of the posterior corneal surface during applanation using a curved femtosecond laser interface and microkeratome cutting head.

PURPOSEnTo evaluate the irregularity of the posterior corneal surface and intrastromal dissection during the preparation of donor tissue for Descemet stripping automated endothelial keratoplasty (DSAEK) using a curved interface femtosecond laser and microkeratome.nnnMETHODSnSixteen human donor corneas unsuitable for transplantation were divided into two groups: a femtosecond (FS) laser group (n=7) using the VisuMax femtosecond laser (Carl Zeiss Meditec) and a microkeratome group (n=9) using the Amadeus II microkeratome (Ziemer Ophthalmic Group). The corneas were fixed on artificial anterior chambers. Horizontal cross-sections were obtained using spectral-domain optical coherence tomography prior to applanation, during applanation, as well as during and after intrastromal dissection at 450-μm corneal depth. The posterior surface and the dissection line were evaluated for irregularity by fitting a second-order polynomial curve using regression analysis and obtaining the root-mean-square error (RMSE). Groups were compared using analysis of variance.nnnRESULTSnThe RMSE of the posterior surface prior to applanation was 9.7 ± 3.1 μm in the FS laser group and 10.2 ± 2.3 μm in the microkeratome group. The RMSE increased to 50.7 ± 9.4 μm and 20.9 ± 6.1 μm during applanation and decreased again to 10.6 ± 1.4 μm and 8.1 ± 1.8 μm after applanation in the FS laser and microkeratome groups, respectively. The RMSE of the intrastromal cut was 19.5 ± 5.7 μm in the FS laser group and 7.7 ± 3.0 μm in the microkeratome group (P<.001).nnnCONCLUSIONSnOur results show significantly greater irregularity with the curved interface femtosecond laser-assisted cleavage compared to microkeratome-assisted corneal dissection, possibly due to applanation-derived deformation of the posterior cornea.

Curvature of iris profile in spectral domain optical coherence tomography and dependency to refraction, age and pupil size - the MIPH Eye&Health Study.

Optical coherence tomography (OCT) of the anterior segment allows quantitative analysis of the geometry of the iris. We performed spectral domain OCT examinations in healthy emmetropic, hyperopic and myopic subjects to investigate iris curvature and its associations.

Expanding the clinical spectrum of COL1A1 mutations in different forms of glaucoma.

BackgroundPrimary congenital glaucoma (PCG) and early onset glaucomas are one of the major causes of children and young adult blindness worldwide. Both autosomal recessive and dominant inheritance have been described with involvement of several genes including CYP1B1, FOXC1, PITX2, MYOC and PAX6. However, mutations in these genes explain only a small fraction of cases suggesting the presence of further candidate genes.MethodsTo elucidate further genetic causes of these conditions whole exome sequencing (WES) was performed in an Italian patient, diagnosed with PCG and retinal detachment, and his unaffected parents. Sanger sequencing of the complete coding region of COL1A1 was performed in a total of 26 further patients diagnosed with PCG or early onset glaucoma. Exclusion of pathogenic variations in known glaucoma genes as CYP1B1, MYOC, FOXC1, PITX2 and PAX6 was additionally done per Sanger sequencing and Multiple Ligation-dependent Probe Amplification (MLPA) analysis.ResultsIn the patient diagnosed with PCG and retinal detachment, analysis of WES data identified compound heterozygous variants in COL1A1 (p.Met264Leu; p.Ala1083Thr). Targeted COL1A1 screening of 26 additional patients detected three further heterozygous variants (p.Arg253*, p.Gly767Ser and p.Gly154Val) in three distinct subjects: two of them diagnosed with early onset glaucoma and mild form of osteogenesis imperfecta (OI), one patient with a diagnosis of PCG at age 4xa0years. All five variants affected evolutionary, highly conserved amino acids indicating important functional restrictions. Molecular modeling predicted that the heterozygous variants are dominant in effect and affect protein stability and thus the amount of available protein, while the compound heterozygous variants act as recessive alleles and impair binding affinity to two main COL1A1 binding proteins: Hsp47 and fibronectin.ConclusionsDominant inherited mutations in COL1A1 are known causes of connective tissues disorders such as OI. These disorders are also associated with different ocular abnormalities, although recognition of the common pathology for both features is seldom being recognized. Our results expand the role of COL1A1 mutations in different forms of early-onset glaucoma with and without signs of OI. Thus, we suggest including COL1A1 mutation screening in the genetic work-up of glaucoma cases and detailed ophthalmic examinations with fundus analysis in patients with OI.

Seizures following subconjunctival 5-FU therapy

Dear Editor, Antiproliferative treatment following glaucoma surgery includes subconjunctival 5-fluorouracil (5-FU) injections as a routine procedure. Cumulative dosage during the postoperative period is adjusted to individual needs ranging from 5 to 75 mg. We report the case of a 68-year-old male Caucasian patient who underwent uneventful trabeculectomy for advanced primary open-angle glaucoma with intraoperative application of Mitomycin C. Under topical anesthesia with tetracaine eye drops, a subconjunctival injection of 5 mg 5-FU was administered on postoperative day 4. A few minutes later, a generalized tonic and clonic seizure occurred lasting for 3 min that ended spontaneously. A second episode of seizures happened 3 h later. The patient did not retain any memory of the episode and amnesia was observed for the immediate postictal period. However, epilepsy was hitherto unknown in this patient nor did his medical history give any hints as to such a condition. Known systemic conditions included arterial hypertension, coronary heart disease, congenital aortic coarctation, hyperlipidemia, and prostate hyperplasia. Neurologic examination including electroencephalography and cranial imaging revealed spike wave complexes, but no specific focus. Thirteen days later, two more subconjunctival injections of 5 mg 5-FU were applied without complications under anticonvulsive therapy with Valproic acid 300 mg twice a day. No more seizures occurred in the domestic environment. When trabeculectomy was performed on the fellow eye 4 months later, 5 mg 5-FU was again applied to prevent bleb scarring without obvious complications. Upon a 5-h interval after the second injection, two more grand-mal convulsions occurred despite permanent therapy with gabapentin 300 mg three times a day and acute therapy with lorazepam 1 mg after the first seizure. Afterwards, the therapy was modified to Valproic acid 600 mg twice a day. 5-fluorouracil is a pyrimidine antimetabolite that prevents DNA synthesis and inhibits RNA processing and function. It quickly penetrates the blood–brain barrier and achieves significant concentrations within the cerebrospinal fluid. Observed neurotoxicity of 5-FU as a commonly used, systemic chemotherapy agent is estimated <1% [1–3], but also up to 5.7% [4, 5] in high-dose chemotherapy. Acute neurotoxicity is dose-related and generally reversible [6]. It typically manifests as encephalopathy with somnolence and confusion or cerebellar syndrome. However, seizures are described in a few cases [3, 6], and in only one case as isolated generalized tonic-clonic seizures [7]. The exact pathways of neurotoxicity are not completely understood. The most plausible pathogenetic mechanism for developing seizures or paresis-like symptoms may be the Krebs cycle blockade by fluoroacetate and fluorocitrate, which results in a reduction of high-energy adenosine triphosphate [2, 8, 9]. Other proposed mechanisms are thiamine deficiency and inherited deficiency of the enzyme dihydropyrimidine dehydrogenase (DPD), which metaboPresentation at a conference Parts of this case report were presented at the 107th Congress of the Deutschen Ophthalmologischen Gesellschaft (DOG), Leipzig

Central Corneal Thickness in Spectral-Domain OCT and Associations with Ocular and Systemic Parameters

Background. Optical coherence tomography (OCT) allows quantitative analysis of the anterior segment of the eye with a noncontact examination. The aim of this study is to analyze associations of central corneal thickness (CCT) as measured by OCT with ocular and systemic cardiovascular parameters. Methods. A cross-sectional study of 734 persons was performed in a working age population. Only healthy eyes were included. A comprehensive ophthalmological examination including refraction, noncontact tonometry, and imaging of the anterior segment by SD-OCT was performed. In parallel, a broad range of systemic cardiovascular parameters were measured. Associations were analyzed using a generalized estimating equations model. Results. CCT measurements showed a significant association with corneal curvature and intraocular pressure: a thinner CCT was associated with a flatter cornea and with lower intraocular pressure (p < 0.001). Age was positively associated with CCT (p < 0.001); all other cardiovascular parameters were not associated. Conclusion. A thinner cornea is associated with a flatter surface and with lower intraocular pressure readings, while there are no independent associations with refraction and systemic cardiovascular parameters. Our findings highlight the value of SD-OCT CCT measurements as a standard tool in anterior segment analysis.

Distribution of Anterior Chamber Angle Width and Correlation With Age, Refraction, and Anterior Chamber Depth-The Gutenberg Health Study.

PURPOSEnScheimpflug imaging allows quantitative analysis of the width of the anterior chamber angle. We report the population-based distribution of the anterior chamber angle width using this noncontact imaging technique and investigate associated factors.nnnMETHODSnA population-based cross-sectional study was carried out in Germany. A comprehensive ophthalmologic examination including refraction, biometry, and Scheimpflug imaging was performed. Automated measurement of the anterior chamber angle was performed in each anterior chamber quadrant. Exclusion criteria were previous ocular surgery or inadequate image quality. Association analyses were carried out to determine independently associated systemic and ocular factors for anterior chamber angle width using a generalized estimating equation model.nnnRESULTSnA total of 3014 subjects (48% female) with a mean age of 58.6 ± 10.4 years were included in this study. The mean anterior chamber angle width was 32.6° ± 5.5°. Statistical analysis revealed an independent association between a smaller anterior chamber angle and female sex, higher age, and more hyperopic refraction. When including biometric parameters, shallow anterior chamber depth, shorter axial length, higher central corneal thickness, and lower corneal power were independently associated with a narrower mean anterior chamber angle width.nnnCONCLUSIONSnThese parameters are considered risk factors for angle-closure glaucoma.

Visualization of corneal vascularization in peripheral hypertrophic subepithelial corneal opacification with OCT angiography

The major goal of this study was to test the hypothesis that in patients with peripheral hypertrophic subepithelial corneal opacification (PHSCO), visualization of corneal vessels is better with optical coherence tomography angiography (OCTA) than with conventional slit lamp microphotography.

Steeper Iris Conicity Is Related to a Shallower Anterior Chamber: The Gutenberg Health Study

Purpose To report the distribution of iris conicity (steepness of the iris cone), investigate associated factors, and test whether pseudophakia allows the iris to sink back. Methods A population-based cross-sectional study was carried out. Ophthalmological examination including objective refraction, biometry, noncontact tonometry, and Scheimpflug imaging (Pentacam®, Oculus) was performed including automated measurement of iris conicity. 3708 phakic subjects, 144 subjects with bilateral and 39 subjects with unilateral pseudophakia were included. Multivariable analyses were carried out to determine independently associated systemic and ocular factors for iris conicity in phakic eyes. Results Mean iris conicity was 8.28°u2009±u20093.29° (right eyes). Statistical analysis revealed associations between steeper iris conicity and shallower anterior chamber depth, thicker human lens and higher corneal power in multivariable analysis, while older age was related to a flatter iris conicity. Refraction, axial length, central corneal thickness, pupil diameter, and intraocular pressure were not associated with iris conicity. Pseudophakia resulted in a 5.82° flatter iris conicity than in the fellow phakic eyes. Conclusions Associations indicate a correlation between iris conicity with risk factors for angle-closure, namely, shallower anterior chamber depth and thicker human lens. In pseudophakic eyes, iris conicity is significantly lower, indicating that cataract surgery flattens the iris.

Suprachoroidal Bleeding after XEN Gel Implantation

Purpose: To report for the first time a clinical case of suprachoroidal bleeding after XEN45 gel implantation. Observations: A 84-year old female patient with pseudoexfoliation glaucoma with intraocular pressure (IOP) (20u2009mmu2009Hg) above target despite maximal IOP-lowering therapy was scheduled for XEN45 gel implantation. The XEN45 gel implantation went without complications and was properly placed in the anterior chamber and beneath the conjunctiva. On the first postoperative day, the patient presented with an IOP of 4u2009mmu2009Hg, a functioning bleb and a deep anterior chamber. On the second day she developed suprachoroidal bleeding. A wait and see strategy was followed and the patient monitored steadily. The bleeding resolved spontaneously after 6 weeks. Conclusions and Importance: Minimally invasive glaucoma surgery is developed to provide a safer and less-invasive option to reduce IOP in glaucoma patients compared with trabeculectomy. Although the concept of the XEN45 gel stent seems to be a favorable to reach IOP-lowering results similar to those of trabeculectomy, complications may be similar, too. We have to keep this in mind when informing patients about surgical options.