Zusammenfassung
Hintergrund: Die vaskuläre Dysregulation wird als Risikofaktor diverser Augenerkrankungen diskutiert. Zweck dieser Studie war die Evaluation der retinalen Gefäßantwort auf Flickerlicht bei gesunden Personen mit vasospastischer Diathese. Patienten und Methoden: 30 gesunde Personen kaukasischen Ursprungs, 18 – 35 Jahre alt, wurden für die Studie rekrutiert. Jeweils 15 Personen bildeten die vasospastische Gruppe, respektive die Kontrollgruppe. Vasospasmus war dabei definiert durch die Anamnese oft kalter Hände, sogar im Sommer, plus übereinstimmendem Resultat in der Nagelfalz-Kapillarmikroskopie. Die Kontrollgruppe wies weder das erste noch das zweite dieser Merkmale auf. Mithilfe des Retinal Vessel Analyser wurde die Reaktion des Gefäßdurchmessers auf Flickerlicht in 1 – 2 Papillendurchmessern Entfernung von der Papille gemessen. Aufgezeichnet wurden 3 Phasen Flickerlicht von 20 s Dauer, gefolgt von einer Grünlichtphase von 80 s Dauer. Die höchste Reaktion auf Flickerlicht wurde in jeder Flickerphase evaluiert und über die 3 Resultate gemittelt. Ergebnisse: Die maximale durchschnittliche Gefäßantwort im Verhältnis zur Basalphase erreichte auf der arteriellen Seite einen Mittelwert ± Standardabweichung von 2,9 ± 1,7 % in der vasospastischen Gruppe und von 4,8 ± 2,6 % in der Kontrollgruppe (t = 2,34; p = 0,025). Die venöse Gefäßantwort war in beiden Gruppen vergleichbar. Schlussfolgerungen: In der Studie wiesen Personen mit vasospastischer Anamnese eine im Vergleich zur Kontrollgruppe veränderte Gefäßreaktion auf Flickerlicht auf.
Abstract
Background: Vascular dysregulation is considered to be a risk factor in several ophthalmic diseases. The purpose of this study was to evaluate the reaction of retinal vessels to flicker light in otherwise healthy subjects with a vasospastic propensity. Patients and Methods: Thirty healthy Caucasians, aged between 18 – 35 years were recruited for this study and grouped into vasospastics, based on a history of frequent cold hands, even in summer, with concordant findings in nailfold capillary microscopy, or as controls, if such a history was absent. The reaction of the retinal vascular diameter to flicker light was observed in a distance of two to three discs diameters away from the optic nerve head with the retinal vessel analyser. Three phases of flicker light of twenty seconds followed by baseline light phases of eighty seconds were recorded. The maximal vasodilatory amplitude of each flicker phase was determined and the results averaged. Results: The maximal average dilatory amplitude at the arterial side reached (mean ± SD) 2.9 ± 1.7 % and 4.8 ± 2.6 % of the baseline amplitude respectively in vasospastic subjects and in healthy controls (t = 2.34; p = 0.025). The reaction at the venous side was statistically comparable in both groups. Conclusions: Otherwise healthy, vasospastic subject disclosed an altered reaction of the retinal vasculature to flicker light in this study.
Schlüsselwörter
Flickerlicht - Netzhaut-Gefäßnetz - Retinal Vessel Analyser - vaskuläre Dysregulation - Vasospasmus
Key words
flicker light - retinal vasculature - retinal vessel analyser - vascular dysregulation - vasospasm
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Konstantin Gugleta, MD
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