Anja M. Palmowski

Influence of photodynamic therapy in choroidal neovascularization on focal retinal function assessed with the multifocal electroretinogram and perimetry.

PURPOSE To study the influence of photodynamic therapy (PDT) on retinal function in patients with a predominantly classic choroidal neovascular membrane. DESIGN Comparative observational study. PARTICIPANTS Sixteen eyes with a choroidal neovascular membrane eligible for PDT were included. METHODS Visual acuity, multifocal electroretinogram (MF-ERG, Electrodiagnostic Imaging, San Mateo, CA) recordings and visual fields (Octopus d32) were obtained before PDT with Visudyne, Novartis AG, Basel, Switzerland, and at follow-up 2 weeks to 3 months later. MAIN OUTCOME MEASURES Visual acuity as well as peak-to-peak amplitudes, peak latencies, and focal differences in the scalar product of the two MF-ERG recordings were analyzed. Mean deviation, loss variance, and the absolute difference in sensitivity in the fields obtained were also analyzed. RESULTS After PDT, mean visual acuity stabilized or improved in 13 eyes. Except for two eyes with a predominantly parafoveolar choroidal neovascular membrane, the MF-ERG contribution from the central 4 degrees was reduced below the normal level. Although it improved slightly after PDT, it remained below the normal range. In the central 7.5 degrees, retinal sensitivity increased by up to 80 dB and within the paracentral 7.5 degrees to 15 degrees, it increased by up to 183 dB in 13 eyes. CONCLUSIONS Consistent with the results of the treatment of age-related macular degeneration with photodynamic therapy (TAP) study, PDT can lead to stabilization of visual acuity. Improvement in parafoveal function can be demonstrated in the central visual field, as well as in MF-ERG recordings, even in patients whose visual acuity remains stable. Therefore, the MF-ERG and central perimetry may aid the assessment of retinal function in treatment trials of patients with age-related macular degeneration.

Melanoma-associated retinopathy: high frequency of subclinical findings in patients with melanoma.

Summary Background Melanoma‐associated retinopathy (MAR) is a paraneoplastic syndrome with symptoms of night blindness, light sensations, visual loss, defect in visual fields, and reduced b‐waves in the electroretinogram. Patients with MAR often suffer from a sudden onset of ocular symptoms that are believed to result from antibody production against melanoma‐associated antigens that cross‐react with corresponding epitopes on retinal depolarizing bipolar cells.

Influence of cataract on the multifocal ERG recording: a pre- and postoperative comparison

To study the influence of cataract on the multifocal electroretinogram (mfERG), 18 patients underwent mfERG recordings prior to and following cataract surgery. The central 50° of the retina were stimulated by 103 hexagons alternating independently between white and black according to a binary m-sequence. The frame rate was 75 Hz. The maximum luminance was 200 cd/m2, the minimum luminance <1 cd/m2with a mean luminance of 100 cd/m2. For each retinal location, the latencies of the first negative peak (N1), the first positive peak (P1) and the second negative peak (N2) as well as the amplitude from N1 to P1 and the amplitude from P1 to N2 of the first order response were obtained. Concentric ring averages around the foveal response were analyzed. Following cataract surgery, the mean amplitude of the response in the central four degrees increased from 37.83 to 42.37 for N1P1 (p= 0.019) and from 39.44 to 47.20 for P1N2 (p= 0.001). To reduce the influence of retest variability, each response average was divided by the recordings overall amplitude. For the central 4 degrees this ratio increased by 0.18 (p= 0.002) for N1P1 and by 0.27 (p< 0.001) for P1N2. Clouding of the optic media such as produced by cataracts has a slight but significant influence on the multifocal ERG.

Multifocal electroretinography (MF-ERG) in age-related macular degeneration

SummaryPurpose: Small areas of retinal pathology may pose diagnostic difficulties. The noninvasive multifocal electroretinogram (MF-ERG) provides a topographical mapping of retinal function. Its role in the diagnosis of macular diseases is examined in age-related macular degeneration (AMD). AMD is a main cause of central visual loss in the elderly population, affecting the second eye in 75 %. Methods: MF-ERG recordings of three patients with AMD were compared to the findings of fundus photography and fluorescein angiography. During the MF-ERG recordings the central 50 ° of the retina was stimulated. The visual stimulus consisted of 241 hexagons that alternated, independently and pseudorandomly, between black and white according to a special predetermined binary sequence. Local retinal response components were extracted using the Fast m-Transform Algorithm. Results: Three of six eyes had undergone cataract surgery with implantation of a posterior chamber lens (PCL). In accordance with an increase in light transmission through PCLs, these eyes showed an increase in the MF-ERG responses. MF-ERG allowed accurate topographic mapping of focal areas of retinal dysfunction in all patients tested. There was good correspondence to anatomical changes detected by fluorescein angiography. Conclusion: The high resolution of the MF-ERG enables detection of small areas of retinal pathology. It thus presents a clinically useful, noninvasive method in the early diagnosis and follow-up of macular disease.ZusammenfassungHintergrund: Kleine Areale retinaler Pathologie können, insbesondere im Anfangsstadium, schwer zu diagnostizieren sein. Das multifokale Elektroretinogramm (MF-ERG) bietet seit kurzem die Möglichkeit der topographischen retinalen Funktionsprüfung. Die Eignung des MF-ERGs in der Diagnostik fokaler retinaler Pathologie soll am Beispiel der altersabhängigen Makuladegeneration (AMD) geprüft werden. Die AMD, die in 75 % bilateral verläuft, ist die häufigste Ursache einer Beeinträchtigung des zentralen Sehvermögens bei älteren Menschen. Patienten und Methode: Die Ergebnisse der MF-ERG-Ableitungen dreier Patienten mit AMD wurden in Bezug zur Fundusfotografie und dem fluoreszenzangiographischen Befund gesetzt. Bei der MF-ERG Ableitung wurden die zentralen 50 ° der Netzhaut stimuliert. Der visuelle Stimulus bestand aus 241 Hexagonen, die anhand einer vorbestimmten, speziellen, binären Sequenz, unabhängig voneinander zwischen Schwarz und Weiß wechselten. Die fokalen, retinalen Reizantworten wurden von der Gesamtableitung mittels dem Fast m-Transform-Algorithmus extrahiert. Ergebnisse: In 3 der 6 untersuchten Augen lag nach extrakapsulärer Kataraktextraktion eine Hinterkammerlinsenimplantation (HKL) vor. In diesen Augen zeigten sich im MF-ERG erhöhte Reizantworten, die mit einer vermehrten Lichtdurchlässigkeit der HKL in Verbindung gebracht werden können. Bei allen Patienten konnten mittels MF-ERG Ableitung fokale Areale retinaler Funktionsstörungen topographisch dargestellt werden. Diese zeigten eine gute Übereinstimmung mit ophthalmoskopisch oder fluoreszenzangiographisch nachweisbaren anatomischen Defekten. Schlußfolgerung: Durch das hohe Auflösungsvermögen können mittels MF-ERG auch kleinste Areale retinaler Pathologie aufgezeigt werden. Die topographische retinale Funktionsprüfung mittels MF-ERG stellt eine sensible, nichtinvasive Ergänzung in der Früherkennung und Verlaufskontrolle von Makulaveränderungen dar.

Follow up in open angle glaucoma. A comparison of static perimetry and the fast stimulation mfERG

Purpose:To compare changes in the mfERG to visual field changes observed in OAG. Methods: Twenty-nine eyes with OAG were included. Visual fields (Octopus d32) and mfERGs (VERIS™) were obtained at a mean interval of 9 months (SD 6 months). MfERG recording parameters were as follows: 103 hexagons stimulated the central 50 degrees. M-sequence 25, stimulus base interval 13.33 ms, Lmax 200 cd/m2, contrast 99%. First (KI) and second (KII) order response components were analyzed for the individual quadrants of the visual field and compared to the corresponding mean deviation (MD) of the static perimetry. Results: Changes in visual field parameters and changes in the mfERG did not differ significantly. Overall, as mean deviation increased there was a tendency for implicit times to increase and for amplitudes to decrease. However, over the follow up interval of 9 months only minor changes were observed. The second order response component correlated best with changes in MD (p < 0.05). These were the correlation between MD and KII N1 (r : 0.36) in the upper temporal field, between MD and KII N2 (r : 0.40) in the upper nasal field and between MD and KII P1 (r : 0.38) in the lower temporal field. When a subgroup of 10 eyes that had been tested at least 3 times over 16.8 months (SD 5.5) was examined there were still only minor changes observed in either parameter. Conclusion: While the changes over time in the mfERG and the visual field showed a reasonable correlation, changes observed in either parameter were extremely small over the time period observed, thus requiring a longer follow up and/or a more sensitive stimulation technique.

Detection of retinal dysfunction in vitelliform macular dystrophy using the multifocal ERG (MF-ERG).

Vitelliform macular dystrophy (VMD) is widely known for an abnormal EOG in the presence of a normal ERG. In this study the multifocal electroretinogram (MF-ERG) is described as an additional tool to detect retinal dysfunction in VMD. Three patients aged 30, 37 and 59 years with VMD and a visual acuity of OD: 0.4; OS 0.05 (patient 1), 1.25 OU (patient 2) and OU: 0.6 (patient 3) underwent additional electrophysiological testing with the MF-ERG. A multifocal-ERG of the central 50 degrees of the retina was obtained using the VERIS ™-system. During recording 103 hexagons flickered according to a binary m-sequence of 215. Mean luminance was 100 cd/m2, contrast was set at 99%. The MF-ERG recordings were compared to age matched control groups. In all three patients the MF-ERG of the central 6 degrees showed reduced amplitudes for N1P1 (first negative peak to first positive peak) and for P1N2 (P1 to the second negative peak). Implicit times were not affected. Therefore the MF-ERG can detect focal retinal dysfunction in VMD which would not be apparent in the summed retinal response recorded with the ganzfeld ERG. In contrast to other diseases, amplitudes rather than implicit times seem to be affected in the MF-ERG of vitelliform macular dystrophy.

The cornea and systemic diseases.

&NA; Corneal involvement in systemic diseases is multifold. Dry eye syndome may be associated with autoimmune diseases. Type I diabetes mellitus shows a positive correlation between HbA1c‐level and dry eye syndrome. Autoimmune diseases and occasionally malignancies may be associated with ulcerative keratitis. Opportunistic infections do not only occur in the immunocompromised patient. Storage diseases can cause corneal deposits that may be of great diagnostic halp. Dermatologic diseases can cause various corneal lesions or opacifications.

Multifocal examination techniques in malingering: case report of a patient with monocular vertical hemianopia.

We wish to report on a patient complaining of monocular vertical hemianopia in whom multifocal stimulation techniques helped to verify malingering. Monocular temporal hemianopia may occur secondary to juxtasellar lesions close and anterior enough to the chiasm to selectively impair the ipsilateral crossing nasal optic nerve fibers, or in conjunction with an occlusion of an anomalous central retinal artery branching. Multifocal electrophysiologic techniques offer help to clarify cases of suspected malingering through simultaneous, objective, non-invasive electrophysiological testing of multiple areas in either hemifield. The multifocal electroretinogram (mfERG) has previously been shown to effectively map retinal function in normals and in patients with retinal dysfunction. Recent studies demonstrated that the multifocal visual evoked cortical potentials (mfVEP) can objectively map dysfunction of the visual pathway from the ganglion cells onward [4, 6]. Graefe’s Arch Clin Exp Ophthalmol (2003) 241:70–71

Differenzierte Untersuchung der Netzhautfunktion bei regionaler Retinitis pigmentosa mit Hilfe des multifokalen Elektroretinogramms

ZusammenfassungHintergrund. Generalisierte Netzhauterkrankungen können mit fokalen Funktionsstörungen beginnen. Diese sind mit speziellen Untersuchungstechniken, wie z. B. dem multifokalen Elektroretinogramm, objektivierbar. Fallbeispiel. Mutter und Tochter zeigten bilaterale sektorförmige, knochenbälkchenartige tapetoretinale Degenerationen der kaudalen Retina mit korrespondierenden kranialen Skotomen in der zentralen statischen Perimetrie und in der kinetischen Perimetrie nach Goldmann. Ergebnisse. Muster-VEP, Muster-ERG, Elektrookulogramm und Ganzfeld-ERG zeigten Normalbefunde. Im skotopischen ERG lagen die Amplituden im unteren Normbereich. Das multifokale Zapfen-ERG der zentralen 50° zeigte in der Reizantwort der ersten Ordnung gegenüber der Norm verringerte Amplituden der Reizantworten sowie eine Zunahme der Latenzzeiten. Schlussfolgerung. Mithilfe des MF-ERGs können im Rahmen der Retinopathia pigmentosa fokale Funktionsausfälle unterschiedlicher Ausprägung objektivierbar dargestellt werden. So kann eine höhere Diagnosesicherheit erreicht und eine Zapfenbeteiligung frühzeitig aufgezeigt werden.AbstractPurpose. Generalized retinal degenerations such as retinitis pigmentosa may manifest with focal retinal dysfunctions. These may be detected objectively by new electrophysiological techniques, such as multifocal electroretinography (ERG). Case report. A mother and daughter, aged 81 and 46 years, showed bilateral caudal bone spiculae formations with corresponding cranial visual field defects in the static perimetry of the central visual field (Octopus) and in the kinetic perimetry (Goldmann). Results. Pattern VEP, pattern ERG, EOG, and cone ERG were within the normal range. The scotopic ERG was in the lower normal range. The multifocal cone ERG of the central 50° showed reduced amplitudes and prolonged latencies in the first-order response component. These findings corresponded to the area of the bone spiculae and the scotomata. Conclusion. Multifocal ERG enables the detection of focal retinal cone dysfunction in segmental retinitis pigmentosa. It is an additional tool that may aid in the diagnosis and classification of this disease.