[Ophthalmological health care of the institutionalized elderly : The OVIS study]. / Ophthalmologische Versorgung in Seniorenheimen : Die OVIS-Studie.

BACKGROUND: Due to demographic change and societal transformation the number of elderly persons living in retirement homes is growing in Germany. Access to health care is more complicated in the setting of nursing homes. Different regional studies suggest unmet ophthalmological health care needs in institutionalized elderly people. This study assessed the current ophthalmological health care structure and supply status in nursing homes in Germany. METHODS: This prospective, multicenter cross-sectional study was conducted by 14 study centers in Germany. Elderly people living in 32 nursing homes were included after approval by the local institutional review boards. A standardized examination was performed which included a detailed medical and ocular history, refraction, visual acuity testing, tonometry, biomicroscopy and dilated funduscopy. Unmet ophthalmological health care needs were documented and the data were analyzed descriptively and via logistic regression modelling. RESULTS: A total of 600 participants (434 women and 166 men) aged 50-104 years were examined of which 368 (61%) had ophthalmological conditions requiring treatment. The most prevalent findings were cataracts (315; 53%), disorders of the eyelids (127; 21%), dry eye disease (57; 10%) and posterior capsule opacification (43; 7%). In 63 (11%) of the participants glaucoma was suspected and 55 (9%) of the examined population had a known diagnosis of glaucoma, of whom one third was not on any or on insufficient anti-glaucomatous therapy. 236 (39%) showed signs of age-related macular degeneration (AMD). Only 52% of the examined cohort had been examined by an ophthalmologist within the last 5 years and 39% stated that they would currently not be able to consult an ophthalmologist. Reported barriers were mainly transport and lack of support. CONCLUSION: This study demonstrates considerable unmet ophthalmological health care needs of the institutionalized elderly in Germany. Novel and reformed models of specialist care provision have to be developed.

[Potential of fMRI for the Functional Assessment of the Pathological Visual System]. / Potenzial von fMRT für die Funktionsüberprüfung des pathologischen Sehsystems.

Current developments in functional magnetic resonance imaging (fMRI) of the human visual system have generated a set of powerful approaches that are of great promise for modern ophthalmology. These make it possible to perform an objective spatially resolved test of visual function in patients with strong visual impairment and even to investigate the functional organisation of the visual cortex in the blind. As a consequence, they open a broad field of applications for functional assessment in ophthalmology and provide fundamental insights into the interplay of pathology and plasticity in the human visual system. This is highlighted by current studies investigating patients with acquired or congenital defects of the macula, or with visual pathway abnormalities, extended retinal damage, and complete blindness. Therapeutic approaches targeting the restoration of visual input are expected to benefit from these fMRI applications, either for the estimation of the success rate of a planned retinal therapy or as an objective high-level biomarker for the readout of therapy success.

[The German Acanthamoeba keratitis register: Initial results of a multicenter study]. / Das Deutsche Akanthamöbenkeratitis-Register : Erste Ergebnisse einer multizentrischen Erhebung.

BACKGROUND AND PURPOSE: In September 2011 the cornea section of the German Ophthalmological Society (DOG) established the first German Acanthamoeba keratitis registry. The data of this multicenter survey are being collected, compiled and evaluated at the Department of Ophthalmology at the Saarland University. The aim of this article is to present an intermediate report. PATIENTS AND METHODS: Data from 172 eyes with Acanthamoeba keratitis were collected during the last 10 years. For this interim report we actually evaluated 121 eyes (60.2 % female patients, average age 41.3 years) and collected the following data: date of onset of symptoms, date and method of diagnosis, initial diagnosis, anamnestic data, clinical symptoms and signs at diagnosis and during follow-up, conservative and surgical therapy. Criteria for inclusion in the Acanthamoeba registry was the established diagnosis of an Acanthamoeba keratitis with at least one of the methods described in this article. RESULTS: Acanthamoeba keratitis could be histologically proven in 55.3 % of the cases, via PCR in 25.6 %, with confocal microscopy in 20.4 % and using in vitro cultivation in 15.5 %. Clinical symptoms and signs in Acanthamoeba keratitis were pain in 67.0 %, ring infiltrates in 53.4 %, pseudodendritiform epitheliopathy in 11.7 % and keratoneuritis in 5.8 %. In 47.6 % of the cases the initial diagnosis was herpes simplex virus keratitis followed by bacterial keratitis in 25.2 % and fungal keratitis in 3.9 %. Acanthamoeba keratitis was the correct initial diagnosis in only 23.2 % of cases. The average time period between first symptoms and diagnosis was 2.8 ± 4.0 months (range 0-23 months). A triple therapy with Brolene® Lavasept® and antibiotic eye drops at least 5 ×/day was used in 54.5 % of eyes (n = 66). Penetrating keratoplasty was performed in 40.4 %, in 18 cases in combination with cryotherapy of the cornea. The mean graft diameter was 7.9 ± 1.1 mm (range 3.5-11.0 mm). The final visual acuity (Snellen visual acuity chart at 5 m) was comparable in the two groups of eyes with (5/40 ± 5/25) and without (5/32 ± 5/25) keratoplasty. CONCLUSION: Acanthamoeba keratitis is a rare and often very late diagnosed disease and two thirds of the cases were initially misdiagnosed. The early recognition of the typical symptoms is crucial for the prognosis of the disease. All ophthalmological departments in Germany are invited to submit further data of all confirmed cases (berthold.seitz@uks.eu), whether retrospectively or prospectively in order to generate an adequate standardized diagnostic and therapeutic approach for this potentially devastating disease.

Motoneuron regeneration accuracy and recovery of gait after femoral nerve injuries in rats.

The rat femoral nerve is a valuable model allowing studies on specificity of motor axon regeneration. Despite common use of this model, the functional consequences of femoral nerve lesions and their relationship to precision of axonal regeneration have not been evaluated. Here we assessed gait recovery after femoral nerve injuries of varying severity in adult female Wistar rats using a video-based approach, single-frame motion analysis (SFMA). After nerve crush, recovery was complete at 4 weeks after injury (99% of maximum 100% as estimated by a recovery index). Functional restoration after nerve section/suture was much slower and incomplete (84%) even 20 weeks post-surgery. A 5-mm gap between the distal and proximal nerve stumps additionally delayed recovery and worsened the outcome (68% recovery). As assessed by retrograde labeling in the same rats at 20 weeks after injury, the anatomical outcome was also dependent on lesion severity. After nerve crush, 97% of the femoral motoneurons (MNs) had axons correctly projecting only into the distal quadriceps branch of the femoral nerve. The percentage of correctly projecting MNs was only 55% and 15% after nerve suture and gap repair, respectively. As indicated by regression analyses, better functional recovery was associated with higher numbers of correctly projecting MNs and, unexpectedly, lower numbers of MNs projecting to both muscle and skin. The data show that type of nerve injury and repair profoundly influence selectivity of motor reinnervation and, in parallel, functional outcome. The results also suggest that MNs' projection patterns may influence their contribution to muscle performance. In addition to the experiments described above, we performed repeated measurements and statistical analyses to validate the SFMA. The results revealed high accuracy and reproducibility of the SFMA measurements.

Differential effects of optic media opacities on simultaneous multifocal pattern electroretinograms and visual evoked potentials.

OBJECTIVE: To identify potential confounds in the comparison of simultaneously acquired multifocal electroretinograms (mfPERGs) and visual evoked potentials (mfVEPs) to pattern reversal stimulation. METHODS: With VERIS Science 5.1.10X monocular mfPERGs and mfVEPs were recorded simultaneously to optimised pattern-reversal stimulation for a reference condition and two filter conditions, i.e. blur and 8% luminance transmission, in two separate experiments in participants with normal vision. The impact of the filter conditions on mfPERG amplitude (P50 and N95 peaks), mfVEP-magnitude (root-mean-squares and signal-to-noise-ratios), and on the response timing was assessed. RESULTS: Blur reduced mfPERG P50 and N95 amplitudes to 16%, 21%, and mfVEP magnitude to 82%. Decreasing stimulus luminance to 8% reduced only the mfPERG (P50 to 72% and N95 to 74%), but delayed both mfPERG and mfVEP responses by 5.3 and 4.6ms, respectively. CONCLUSIONS: Comparatively minor stimulus manipulations, mimicking optic media opacities, had a differential effect on mfPERGs and mfVEPs magnitudes. SIGNIFICANCE: Simultaneous mfPERG/mfVEP recordings are a promising approach to compare retinal and cortical function, but caution must be exerted in the interpretation of response differences due to incongruent response characteristics.

[General substance classification and pharmacology of glaucoma]. / Allgemeine Substanzklassen und Pharmakologie bei Glaukom.

The pharmaceutical therapy of glaucoma dates back to 1875 when Weber introduced pilocarpine into the medicinal treatment of glaucoma. Since then there has been a continuous development of topical antiglaucoma therapy whereby the main developments date back to the 1980s and 1990s. All forms of medicinal therapy aim at lowering the intraocular pressure and achieve this either by inhibiting aqueous humor secretion into the ciliary body or by enhancing physiological drainage routes along Schlemm's canal. This article gives an overview over the most important classes of antiglaucoma drugs, the indications and contraindications as well as pharmacological characteristics. The focus lies on the market of combination and generic drug preparations that is currently rapidly developing and therefore needs to be discussed in detail.

[Clinical results of encapsulated bleb removal after Ahmed glaucoma valve implants]. / Klinische Ergebnisse von Kapselausschneidungen nach Ahmed-Implantaten.

In refractory glaucoma, surgical intervention is required which in most cases aims at artificially increasing the drainage of aqueous humor from the eye. One surgical option used with increasing frequency is the implantation of episcleral glaucoma drainage devices (GDD). The clinical success of such devices is often limited by excessive wound healing and scar formation around the base plate of the implant. In severe cases, which seem to occur most frequently in pediatric patients, the rapid formation of a thick, water-impervious fibrotic capsule within months after initial implantation leads to diminished aqueous resorption and an increase in intraocular pressure to presurgical values. Often additional surgical interventions become necessary. Excision of the fibrotic tissue around the implant may help to salvage function and might be an alternative to the more commonly practiced implantation of an additional GDD. In the case series presented here the surgical method of capsular revision is described and the clinical outcome in 11 eyes from 10 patients is reported.

[Pathophysiology of fibrotic encapsulation of episcleral glaucoma drainage implants: modification for improvement of clinical results]. / Pathophysiologie der fibrösen Abkapselung epibulbärer Glaukom-Drainage-Implantate : Modifikation zur Verbesserung der klinischen Ergebnisse.

Episcleral glaucoma drainage implants (GDI) are being used increasingly more as a surgical option for lowering intraocular pressure (IOP). One of the main reasons for failure to control IOP is the formation of water-impervious fibrotic tissue around the base plate of GDIs that prevents effective resorption of the drained aqueous humor and thus leads to an increase in IOP. Surgical removal of the fibrotic tissue can often rescue implant function; however, repeated encapsulation can often not be prevented and necessitates additional interventions up to the removal of the implant itself. The reasons for the fibrotic reaction are not fully understood. Apart from patient-dependent mechanisms that are also involved in bleb scarring after trabeculectomy, implant properties, such as size, shape, surface properties and biomaterial probably contribute to the encapsulation process. Based on the literature on this topic this article looks at possible ways of improving the design of currently used drainage implants including the potential use of GDIs as a carrier for antifibrotic medication released at low doses over an extended period of time.

[Tube versus trabeculectomy study]. / Tube versus Trabekulektomie (TVT)-Studie.

Epibulbar glaucoma drainage devices have been only slightly modified since their introduction more than 40 years ago. Having been used primarily in only difficult cases with a poor prognosis (and therefore with poor clinical results) the recently published trabeculectomy versus tube study (TVT) led to a change in our understanding of these devices. In this study epibulbar glaucoma drainage devices (here the Baerveldt device) were employed for early implantation (in some cases as primary glaucoma surgery intervention). Being sceptically monitored the results over the first 5 year clearly showed an almost equal or even better outcome in comparison to trabeculectomy. Despite these good results a critical evaluation seems mandatory mainly because of the unsolved problems concerning late complications. Late tube erosion with subsequent blebitis and enophthalmitis as well as late base plate encapsulation need to be mentioned here. The latter leads to thick fibrous tissue around the base plate resulting in an increase of intraocular pressure (IOP). Late corneal decompensation is also a late complication the pathomechanism of which is only poorly understood. Solving and treating such late complications are often troublesome and time consuming. Future experiments should lead to development of new drainage implant designs and the bulk material should be enhanced and optimized to increase clinical surgical results.

Deficient functional recovery after facial nerve crush in rats is associated with restricted rearrangements of synaptic terminals in the facial nucleus.

Crush injuries of peripheral nerves typically lead to axonotmesis, axonal damage without disruption of connective tissue sheaths. Generally, human patients and experimental animals recover well after axonotmesis and the favorable outcome has been attributed to precise axonal reinnervation of the original peripheral targets. Here we assessed functionally and morphologically the long-term consequences of facial nerve axonotmesis in rats. Expectedly, we found that 5 months after crush or cryogenic nerve lesion, the numbers of motoneurons with regenerated axons and their projection pattern into the main branches of the facial nerve were similar to those in control animals suggesting precise target reinnervation. Unexpectedly, however, we found that functional recovery, estimated by vibrissal motion analysis, was incomplete at 2 months after injury and did not improve thereafter. The maximum amplitude of whisking remained substantially, by more than 30% lower than control values even 5 months after axonotmesis. Morphological analyses showed that the facial motoneurons ipsilateral to injury were innervated by lower numbers of glutamatergic terminals (-15%) and cholinergic perisomatic boutons (-26%) compared with the contralateral non-injured motoneurons. The structural deficits were correlated with functional performance of individual animals and associated with microgliosis in the facial nucleus but not with polyinnervation of muscle fibers. These results support the idea that restricted CNS plasticity and insufficient afferent inputs to motoneurons may substantially contribute to functional deficits after facial nerve injuries, possibly including pathologic conditions in humans like axonotmesis in idiopathic facial nerve (Bell's) palsy.

[Preservatives from the perspective of glaucoma surgery]. / Konservierungsmittel aus Sicht der Glaukomchirurgie.

Trabeculectomy is still the gold standard in the surgical treatment of glaucoma patients. Development of a bleb is the primary goal of this procedure and the conjunctival status is therefore decisive. Only a good functioning bleb renders good intraocular pressure (IOP) control. Scar tissue formation leads to bleb failure which is quite common despite the use of antiproliferative agents, such as mitomycin C and 5 fluoruracil. Wound healing is important and is influenced and impaired by the chronic use of topical antiglaucoma drugs. Therefore, complete abstinence is recommended from 4-6 weeks prior to a planned trabeculectomy; however, it seems mandatory to completely abolish preservatives such as drops containing benzalkonium chloride to enhance trabeculectomy success rates.

[Morphological alterations induced by preservatives in eye drops]. / Morphologische Veränderungen durch Konservierungsmittel in Augentropfen.

A large number of experimental and clinical investigations carried out recently have confirmed that the chronic application of eye drops induces significant cytological and histological impairment in ocular tissues. It is also generally accepted that preservatives are the components responsible for the observed changes. The most commonly used preservative in ophthalmology is benzalkonium chloride (BAC), which has a relatively high toxicity. Possible consequences of preservatives on the eye are chronic inflammation and subsequent fibrosis of the subconjunctiva and cell loss and structural changes in the conjunctival epithelium as well as in the epithelial and endothelial layers of the cornea. Frequently, dry eye symptoms occur or deteriorate during therapy. During the last few years new preservatives have been developed which seem to have fewer side effects; however, relatively little data are available with regard to these new substances. To minimize impairments of the eye, preservative-free formulations should be considered for therapy.

[Osteogenesis imperfecta and glaucoma. A case report]. / Osteogenesis imperfecta und Glaukom. Eine Fallbeschreibung.

Osteogenesis imperfecta (OI) is a connective tissue metabolic disorder with autosomal inheritance. Ocular involvement includes blue sclera, myopia, glaucoma and keratoconus in addition to bone synthesis defects. We report the case of a male patient with OI who suffered from progressive visual field defects and advanced glaucomatous optic atrophy and underwent trabeculectomy on both eyes. Intraocular pressures (IOP) of 7-11 mmHg were measured 1 year postoperatively. This report illustrates peculiarities in the surgical therapy of open angle glaucoma in patients with OI as well as the options for complication management.