H. Gerding

Einfluss von lokal appliziertem Lidocain auf die Ausprägung des okulokardialen Reflexes

Introduction: The oculocardiac reflex causes severe bradycardic arrhythmias and is a frequent complication during surgical manipulation at the medial rectus muscle. The purpose of this study was to evaluate the influence of lidocaine administered topically on the muscle on the incidence of the oculocardiac reflex.Patients and methods: After obtaining informed consent, 140 patients with strabism or retinal surgery were included in this study. All patients received standard premedication and anesthesia and were randomly assigned to two groups. Patients (n = 70) randomly assigned to the first group received 1 mg/kg lidocaine applied topically to the muscle after opening the conjunctiva. Individuals in the placebo group received the same volume of saline (0.9%). Surgical stimulation occurred 5 min after administration of the drug. The study parameters (blood pressure/heart rate) were recorded before and after stimulation of the oculocardiac reflex caused by routine surgical preparation.Results: Topical administration of lidocaine reduced the incidence of the oculocardiac reflex (86.1% vs 37.1%), and the frequency of severe bradycardiac arrhythmias was also significantly reduced (40 vs. 2.9%). Cardiac arrest for longer than 10 s did not occur in the lidocaine group. In the control group this phenomenon was observed in 14.8%.Problemstellung: Der okulokardiale Reflex führt, speziell nach chirurgischer Manipulation am M. rectus medialis, zu gravierenden bradykarden Rhythmusstörungen. Ziel dieser Studie war es, den Einfluß von lokal auf den Muskel appliziertem Lidocain auf die Inzidenz des Reflexes zu überprüfen.Methode: Nach Einwilligung wurde die Untersuchung an 140 Patienten im Rahmen von Strabismus- und Netzhautchirurgie durchgeführt. Prämedikation und Narkoseverfahren wurden standardisiert. Randomisiert wurde bei 70 Patienten nach Eröffnung der Bindehaut 5 min vor der chirurgischen Manipulation 1 mg/kg KG Lidocain lokal auf den M. rectus medialis appliziert. Die andere Hälfte des Patientenkollektivs erhielt das gewichtsbezogene Volumen NaCl. Vor und nach der Stimulation des okulokardialen Reflexes durch Muskelzug im Rahmen der routinemäßigen chirurgischen Manipulation wurden die hämodynamischen Parameter, arterieller Mitteldruck (MAP) und Herzfrequenz (HR), mittels Dinamap® und EKG ermittelt.Schlußfolgerungen: Unter lokaler Lidocainanwendung findet sich eine signifikant geringere Manifestation des okulokardialen Reflexes (86,1% vs. 37,1%). Schwerwiegende bradykarde Rhythmusstörungen können durch dieses Verfahren verhindert werden (40% vs. 2,9%). Ein Sinusarrest mit einer Dauer von 10 s, der in der Kontrollgruppe in 14,8% der untersuchten Fälle beobachtet werden konnte, wurde nach Lidocaingabe nicht mehr registriert.

Comparison of Two Partial Coherence Interferometry Devices for Ocular Biometry

BACKGROUND An estimation of the repeatability of the Lenstar LS 900 biometry parameters and comparison of these measurements to those evaluated with the IOLMaster were carried out. PATIENTS AND METHODS Axial length, corneal curvature, anterior chamber depth, central corneal thickness and lens thickness measurements were performed in 145 eyes using the Lenstar LS 900, while axial length, corneal curvature and anterior chamber depth were measured using the IOLMaster. The repeatability coefficients and the coefficients of variation were assessed. The Bland-Altman plots and the regression analysis were applied to evaluate the differences between the two methods. RESULTS Axial length was the most repeatable parameter and lens thickness the most variable. Axial length and corneal curvature measurements by IOLMaster and Lenstar LS 900 showed a good correlation (mean differences: 0.03 and 0.01 mm). Anterior chamber depth measurements by the two instruments resulted in a difference of 0.2 mm (all p values < 0.0001). Regression analysis showed a highly significant correlation between measurements by the two methods. Correlation coefficients were: axial length 0.999, corneal curvature 0.983, anterior chamber depth 0.925 (p < 0.0001). Bland-Altman plots demonstrated that measurements by the tested devices were closely related without systematic effects in the range of evaluated data. CONCLUSION Lenstar measurements yielded a high repeatability and correlate highly significant with the IOLMaster measurements.

Ranibizumab in retinal vein occlusion: treatment recommendations by an expert panel

Retinal vein occlusion (RVO) is a common cause of retinal vascular disease, resulting in potentially irreversible loss of vision despite the existence of several therapeutic options. The humanised monoclonal antibody fragment ranibizumab binds to and inhibits vascular endothelial growth factor, a key driver of macular oedema in RVO. In 2010, ranibizumab was approved in the USA for the treatment of macular oedema in RVO and, in 2011, ranibizumab was approved in the European Union for the treatment of visual impairment caused by macular oedema secondary to RVO in branch and central RVO. Ranibizumab provides an additional therapeutic option for this complex disease: an option that was not fully considered during the preparation of current international guidelines. An expert panel was convened to critically evaluate the evidence for treatment with ranibizumab in patients with visual impairment caused by macular oedema secondary to RVO and to develop treatment recommendations, with the aim of assisting physicians to optimise patient treatment.

Outcome of surgery after macula-off retinal detachment – results from MUSTARD, one of the largest databases on buckling surgery in Europe

Purpose:  To evaluate the anatomical success rate of scleral buckling surgery in the treatment of rhegmatogenous retinal detachment and to evaluate the differences in outcome between patients suffering macula‐off retinal detachment and those without a macular involvement.

Enucleation and development of cluster headache: a retrospective study

BackgroundCluster headache (CH) is a neurovascular, primary headache disorder. There are, however, several case reports about patients whose CH started shortly after a structural brain disease or trauma. Motivated by a patient who developed CH 3 weeks after the removal of an eye and by similar case reports, we tested the hypothesis that the removal of an eye is a risk factor for CH.MethodsA detailed headache questionnaire was filled out by 112 patients on average 8 years after enucleation or evisceration of an eye.ResultsWhile 21 % of these patients experienced previously unknown headaches after the removal of an eye, no patient fulfilled the diagnostic criteria for CH.ConclusionOur data does not suggest that the removal of an eye is a major risk factor for the development of CH.

Elektrostimulation des visuellen Systems: Von therapeutischer Empirie zur Entwicklung von Sehprothesen

ZusammenfassungDie Erprobung elektrischer Stimulation am visuellen System lässt sich im Wesentlichen drei aufeinander folgenden Entwicklungsabschnitten zuordnen: einer empirischen, einer diagnostischen und einer therapeutisch ausgerichteten Phase. Hierbei wurden die ersten elektrischen Stimulationen des visuellen Systems im 18. Jahrhundert aus wissenschaftlichem Interesse an Tieren durchgeführt. Trotz fehlender klinisch-pathologischer Kenntnisse erfolgten damals auch vereinzelt Stimulationsversuche wagemutig in therapeutischer Absicht an blinden Patienten. Mit zunehmenden neurologischen und technologischen Kenntnissen wurden hundert Jahre später Versuche einer gezielten Anwendung elektrischer Ströme am visuellen System des Menschen im Rahmen neuer elektrophysiologisch-diagnostischer Untersuchungsmethoden unternommen. Ab der späten Mitte des 20. Jahrhunderts setzten systematische Bemühungen ein, blinden Patienten, unter Zuhilfenahme elektrotechnisch arbeitender Implantate, eine visuell verwertbare Bildinformation zu vermitteln. Inzwischen haben sich weltweit neun Forschungsgruppen mit z. T. unterschiedlichen Arbeitsmodellen zur Erarbeitung epi-, subretinal, kortikal oder sehnervgebundener Prothesen etabliert. Die historische Entwicklung der elektrophysiologischen Stimulation des visuellen Systems und aktuelle Fortschritte bei der Konzeption von Sehprothesen sollen dargestellt werden.AbstractThe investigation of the influence of electrical stimulation on the visual system can be subdivided into empirical, diagnostic and therapeutic phases of development. The first electrical stimulations of the visual system in animals dating back to the eighteenth century represent empirical approaches well before knowledge on the principles of bioelectrical nerve activity was available. Despite this lack of understanding, attempts were made at that time to treat blind people by electrical stimulation. More than 100 years later, with the advancement of technology and knowledge on nerve function, attempts were made to establish various methods of electrical stimulation for the diagnosis of different diseases of the visual system. For more than 30 years attempts to develop electrical devices have been made to by-pass defects of the visual system and to restore basic orientation. Presently nine different groups world-wide are focusing on retinal, optic or cortical implants. A short review on the historical use of electrical stimulation and new therapeutical attempts are given in this paper.

Three Years Follow-up Results of Ranibizumab Treatment for Choroidal Neovascularization Secondary to Pathologic Myopia

BACKGROUND Choroidal neovascularization (CNV) secondary to pathological myopia (PM) is one of the main causes of severe visual impairment in patients younger than 50 years. In this analysis we want to demonstrate the long-term results of Ranibizumab treating CNV secondary to PM. PATIENTS AND METHODS We retrospectively analysed 15 treatment naive eyes of 13 patients (10 women, 3 men, mean age: 61.5, SD 11.6, range: 41-80) with visual impairment due to CNV secondary to PM, which were treated with ranibizumab. Criteria for re-treatment were reduction of visual acuity and/or activity in OCT or fluorescence angiography. RESULTS We applied a mean of 3 injections (standard deviation [SD] 2.5, range: 1-8) ranibizumab during a mean period of 39.6 months (SD 5.3, range: 31-52). The spherical equivalent was -12.4 diopters ± 4.1 (range -7.5 to -20.5 diopters). Before the first injection mean visual acuity (logMAR) was 0.69 ± 0.26. After one month visual acuity improved to 0.39 ± 0.23 (p = 0.002), after 3 months to 0.30 ± 0.22 (p = 0.002) and after 6 months up to 0.30 ± 0.22 (p = 0.002). After 12 months visual acuity was 0.30 ± 0.22 (p = 0.001) and after 24 months 0.30 ± SD 0.24 (p = 0.001). 11 patients reached a follow-up of at least 36 months and visual acuity was 0.30 ± 0.13 (p = 0.001). CONCLUSIONS Treating CNV secondary to PM with ranibizumab during a follow-up of 36 months, we found considerable improvement of visual acuity. Compared to treatment of CNV secondary to exudative age-related macular degeneration, CNVs secondary to PM seem to respond faster to ranibizumab treatment and less injections are neccessary to reach stabilization.

Symptomatic cicatrizial occlusion of canaliculi after insertion of herrick lacrimal plugs

PURPOSE To report severe symptomatic complications following bilateral insertion of Herrick lacrimal plugs. DESIGN Interventional case report. METHODS Bilateral clinical, surgical, and histologic findings in a patient with surgical revision of canaliculi after plug insertion. RESULTS A 55-year-old patient presented with recurrent inflammation, discharge, and epiphora 24 months after insertion of lacrimal plugs; surgical intervention and partial resection of the cicatrized canaliculi was necessary. Light microscopic histology revealed canaliculi destruction, reactive tissue embedding of the plugs, and dissociated plug material. CONCLUSIONS The application of Herrick lacrimal plugs may not be reversible and may require invasive surgical intervention.

A dummy orbit for training in diagnostic procedures and laser surgery with enucleated eyes

PURPOSE A dummy orbit for enucleated eyes was developed for training residents in diagnostic and surgical procedures. METHODS Porcine eyes were used to construct the model. The device is made of black anodized metal. The final prototype was tested for ease of use and optical quality. Principal elements are an adjustable eye support, a cylinder, and a removable ring. RESULTS The dummy orbit and enucleated eye allow direct and indirect ophthalmoscopy; inspection with contact lenses, including gonioscopy; and retinal laser coagulation using contact lenses. Laser trabeculoplasty, argon laser trabeculotomy, Nd:YAG laser iridectomy, and Nd:YAG laser capsulectomy are possible, as well as training in tonometry and ultrasonography techniques. CONCLUSION The dummy orbit is a valuable aid for teaching and training in diagnostic and laser surgery procedures with nondissected enucleated eyes.

Rhegmatogene Netzhautablösungen Saisonale Variation der Häufigkeit

SummarySeasonal variations in the relative incidence of rhegmatogenous retinal detachment were reported as a trend in several studies on the database of relatively limited cohort sizes.Patients and methods: An analysis on this topic was performed with a long-term database. A total of 3073 files of patients with rhegmatogenous retinal detachment, covering 11 years of observation, were reviewed for this study. Patients with signs of long-standing detachment or other predisposing diseases were excluded, so that a basic study population of 2314 patients remained for the analysis.Results: The averaged seasonal incidence of rhegmatogenous detachments revealed a significant (P<0.005) mid-summer peak (n in July = 228) and a winter trough (mean of December – January = 161; difference = 36%). Phase and curve fitting of the seasonal variations in the number of retinal detachment cases was similar to the seasonal variation of the astronomic duration of the day (P<0.001). The relation was closer compared to the average duration of light exposure per day calculated from behavioural data and the astronomic length of light phase (P<0.0002).Conclusion: This long-time study revealed a close correlation of the relative seasonal incidence of retinal detachment and the seasonal variation of light hours per day. So far, this observations cannot be explained pathogenetically. Two basic hypotheses ought to be investigated further: (1) The influence of light on the generation of toxic oxygen radicals and the subsequent destruction of the vitreous and (2) possible light-induced changes in vitreoretinal adhesion.ZusammenfassungJahreszeitliche Variationen der Häufigkeit rhegmatogener Netzhautablösungen deuten sich als Trend in verschiedenen Studien unterschiedlicher Fallzahl an.Patienten und Methode: Eine entsprechende Erhebung wurde an einem Kollektiv von 3073 Patienten der Universitäts-Augenklinik Münster über einen Beobachtungszeitraum von 11 Jahren vorgenommen. Unter Beachtung verschiedener Ausschlußkriterien (Aphakie-, Pseudophakieamotio, traumatische Genese, klinische Zeichen einer langbestehenden Amotio, andere prädisponierende Faktoren) verkleinerte sich das Studienkollektiv auf 2314 Patienten.Ergebnisse: Zu verzeichnen waren eine saisonale Variation der Häufigkeit von rhegmatogenen Netzhautablösungen mit einem deutlichen Maximum in den Sommer- und einem Minimum in den Wintermonaten (p<0,005) und eine hochsignifikante Korrelation der monatlichen Häufigkeit von Netzhautablösungen zur durchschnittlichen astronomischen Tageslänge (p<0,001). Eine statistisch noch deutlichere Beziehung ergab die Korrelation mit einer normierten tageszeitlich erlebten Hellphase (p<0,0002).Schlußfolgerung: Die dieser Koinzidenz zugrundeliegenden pathogenetischen Zusammenhänge sind nicht bekannt. Es sind v. a. 2 alternative Kausalzusammenhänge zu diskutieren: Der Lichteinfluß auf die Genese toxischer, an der Glaskörperdestruktion beteiligter Sauerstoffradikale und mögliche Variationen der Pigmentepithel-Retina-Adhärenz.