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P Bischoff

Publications and source records attributed to P Bischoff.

At least 37 records · Page 2Linked to original sources

[Simultaneous ICG- and fluorescein-angiography for fundus examination].

BACKGROUND: An indocyanine-green (ICG) angiography is rarely used as the only diagnostic procedure. Almost always it is performed additionally to a fluorescein angiography. The use of simultaneous ICG and fluorescein (SIF) angiography therefore makes sense. Several examples for the application of SIF-angiography are presented. MATERIALS AND METHODS: SIF-angiography was performed using a 2-wavelength scanning laser ophthalmoscope (SLO). Images were digitally recorded in real time with a graphics workstation. The following cases will be presented: choroidal neovascularization in age-related macular degeneration, choroidal hemangioma, inflammatory fundus disease (APMPPE) and idiopathic polypoidal choroidal vasculopathy. RESULTS: ICG and fluorescein angiography can be simultaneously recorded with the 2-wavelenghth SLO. The quality of the combined pictures is comparable to single-channel recordings of separate ICG and fluorescein images. We show results of the above mentioned cases. CONCLUSIONS: SIF angiography is time efficient and allows precise comparison and analysis of the transit of both dyes through retinal and choroidal circulation. The topographic relation of pathologic findings in ICG angiograms with the critical retinal vascular landmarks is facilitated.

Adult↗

[Automatic measurement of dye filling of simultaneous digital ICG- and fluorescein angiography sequences].

BACKGROUND: The ICG filling is supposed to be faster than Fluorescein filling. Interestingly the filling characteristics of these dyes were never correlated directly using precise quantitative methods. Since ICG and Fluorescein are injected as a mixture, the simultaneous 2-channel angiography provides a suitable method to correlate the filling characteristics of the dyes. MATERIAL AND METHODS: The simultaneous ICG and Fluorescein angiograms were recorded with a Rodenstock Scanning Laser Ophthalmoscope. The angiographic images were digitized real-time with a graphic workstation. Filling characteristics of the two dyes was calculated after off-line eye tracking in different regions of interests (ROIs) on the central retina. RESULTS: The Fluorescein filling was faster than the ICG filling in 56.5% of our patients. In 26% of our patients was a mixed filling detectable. Depending on the position of the ROIs the Fluorescein or ICG filling was faster. In only 17.5% of our cases was the ICG filling faster than the Fluorescein filling. CONCLUSION: Our results show that Fluorescein filling in more than 50% of the cases is faster than ICG filling and only a minority of the patients has a faster ICG filling. According to our experience the filling pattern of the two dyes is individual, there is no rule of thumb for the filling.

Angiography, Digital Subtraction↗

Topography of clonidine-induced electroencephalographic changes evaluated by principal component analysis.

BACKGROUND: Principal component analysis is a multivariate statistical technique to facilitate the evaluation of complex data dimensions. In this study, principle component analysis was used to reduce the large number of variables from multichannel electroencephalographic recordings to a few components describing changes of spatial brain electric activity after intravenous clonidine. METHODS: Seven healthy volunteers (age, 26 +/- 3 [SD] yr) were included in a double-blind crossover study with intravenous clonidine (1.5 and 3.0 microg/kg). A spontaneous electroencephalogram was recorded by 26 leads and quantified by standard fast Fourier transformation in the delta, theta, alpha, and beta bands. Principle component analysis derived from a correlation matrix calculated between all electroencephalographic leads (26 x 26 leads) separately within each classic frequency band. The basic application level of principle component analysis resulted in components representing clusters of electrodes positions that were differently affected by clonidine. Subjective criteria of drowsiness and anxiety were rated by visual analog scales. RESULTS: Topography of clonidine-induced electroencephalographic changes could be attributed to two independent spatial components in each classic frequency band, explaining at least 85% of total variance. The most prominent effects of clonidine were increases in the delta band over centroparietooiccipital areas and decreases in the alpha band over parietooccipital regions. Clonidine administration resulted in subjective drowsiness. CONCLUSIONS: Data from the current study supported the fact that spatial principle component analysis is a useful multivariate statistical procedure to evaluate significant signal changes from multichannel electroencephalographic recordings and to describe the topography of the effects. The clonidine-related changes seen here were most probably results of its sedative effects.

Adult↗

Ex vivo determination of the effect of whole-body exposure to fast neutrons on murine spleen cell viability and apoptosis.

The effects of high-linear energy transfer (LET) radiations on lymphoid tissues and lymphocytes are not well understood. As a first approach to delineate these effects, the present work was conducted to assess the effects of high-LET radiations on murine spleen cells ex vivo and in vitro. BALB/c mice were irradiated whole-body with 65 MeV neutrons or 15 MV X rays at doses ranging from 0.2 to 3 Gy. Spleens were removed 1 day postirradiation and weighed, and single cell suspensions were prepared and cultured for several days. Apoptosis occurring in vitro was determined at different times by flow cytometry analysis of cells labeled with propidium iodide. It was found that irradiation with fast neutrons reduced spleen weight and cellularity to a greater extent than photons. Considering the spleen cellularity as end point, the relative biological effectiveness (RBE) of fast neutrons was 2. However, for both modes of irradiation, apoptosis of recovered spleen cells in vitro increased as a function of dose and the duration of culture. The level of apoptosis occurring at various times postirradiation was found to be identical for high- and low-LET radiations. Taken together, these results suggest that external as well as cellular factors might differentially modulate the sensitivity of lymphocytes to fast neutrons and photons.

Animals↗

Molecular screening of potential HNPCC patients using a multiplex microsatellite PCR system.

Microsatellite instability (MSI) is a molecular hallmark of the H ereditary N on- P olyposis C olorectal C ancer (HNPCC) syndrome occurring in about 80-90% of the tumours and also in sporadic tumours of different organs, albeit at lower frequency. Highly unstable colorectal tumours (MSI-H) have different histopathological features and tend to have a better prognosis compared to neoplasms without (MSS) or with low levels of microsatellite instability (MSI-L). Since MSI classification allows the identification of potential HNPCC patients and might represent a valuable diagnostic parameter an increasing demand for high-throughput microsatellite analysis will arise. Therefore, we have adapted five diagnostic microsatellites, m(odified) ACTC, mBAT26, mD5S107, mD5S406 and mD13S153, to allow coamplification. Using this multiplex polymerase chain reaction (PCR) system 29 colorectal tumour tissues with known MSI status could be unambiguously identified as MSI-H (13 cases) or MSI-L/MSS (16 cases). Highly unstable colorectal tumour detection frequency of individual markers reached 77% (mD5S406), 85% (mACTC), 85% (mD5S107), 92% (D13S153) and 100% (mBAT26) showing similar sensitivity but improved specificity as compared with a microsatellite reference panel. In a prospective analysis of 31 colorectal tumours, the multiplex PCR system identified five MSI-H cases. Multiplex MSI PCR is a time saving and cost-effective method not restricted to specific technical equipment and applicable to a variety of microsatellite-based genotyping approaches.

Colorectal Neoplasms↗

Primary liver disease as a determinant for acute rejection after liver transplantation.

BACKGROUND: Graft rejection and infection remain major problems following liver transplantation; both are heavily influenced by the immunosuppressive regimen. Despite the disparity in the primary disease leading to transplantation, all patients receive the same posttransplant immunosuppressive treatment in a given center. The aim of this study is to detect a possible effect of the underlying disease on the incidence of early acute rejection episodes after orthotopic liver transplantation (OLT). PATIENTS AND METHODS: Retrospective analysis on all 101 consecutive liver transplants performed in 95 patients between 1983 and March 1998; five of these patients, surviving less than 30 days, were not included. The immunosuppressive regimen was based on conventional triple therapy during the whole study period. The diagnosis and treatment of acute rejection within the first 30 days post-OLT was uniform throughout the whole study period. RESULTS: Though there were no differences with respect to patients' characteristics [age, child classification, number of HLA-mismatches or cytomegalovirus (CMV)-serocompatibility], patients with primary biliary cirrhosis (PBC) showed a significant increase of acute rejection after OLT compared with the other patients transplanted for other liver diseases (P = 0.024). The incidence of infection was not elevated in patients transplanted for PBC when compared with other diagnoses. CONCLUSION: Our results indicate that primary liver disease may be a determinant for acute graft rejection in PBC. Furthermore, these results suggest that immunosuppressive regimens based on the underlying disease should be considered.

Acute Disease↗

[Macular edema: from symptom to diagnosis].

BACKGROUND: In this study, the "Macular edema" syndrome is examined in detail from the symptoms right through to the diagnosis. The 9 most important differential diagnoses are also listed, as well as a summary of the currently applicable therapy recommendations. MATERIAL AND METHODS: This overview is based on existing literature as well as own case studies. RESULTS: The symptoms of macular edema consist of visual acuity deterioration, micropsy, metamorphopsy, reduced colour perception, as well as central or paracentral scotoma. Ophthalmologist checks should include a case history (age, diabetes, hypertonia, allergies, cataract surgery?), a detailed examination of the fundus, if possible with a slit-lamp and a contact or non-contact lens, whereby one must pay attention here to the swelling of the retina as well as the presence of hard exsudates in the macular region. It is important to use fluorescence angiography in this case, to achieve a correct differential diagnosis, and eventually for treatment. This angiography may equally reveal a capillary leakage, a cystoid macular edema, a leaking point or a choroidal neovascularization. The differential diagnosis can be divided into the following commonly-occurring groups: age-related macular degeneration/macular edema after a branch or central retinal vein thrombosis/central serous chorioretinopathy/Irvine-Gass syndrome after cataract operation/uveitis/epiretinal fibroplasia/juxtafoveal retinal teleangiectasis and tumors (choroidal melanoma, metastasis and hemangioma). TREATMENT: Apart from the seldomly applicable causal therapy, the following treatments can be used: laser photocoagulation, anti-inflammatory and rinse medication, and in some cases vitrectomy as well as a low dosage of radiation therapy. CONCLUSIONS: In the case of macular edema the ophthalmologist's responsibility is to perform a differential diagnosis and recommend appropriate and sensible methods or treatment.

Diagnosis, Differential↗

Middle latency auditory evoked responses and electroencephalographic derived variables do not predict movement to noxious stimulation during 1 minimum alveolar anesthetic concentration isoflurane/nitrous oxide anesthesia.

UNLABELLED: The electroencephalogram (EEG) and middle latency auditory evoked responses (MLAER) have been proposed for assessment of the depth of anesthesia. However, a reliable monitor of the adequacy of anesthesia has not yet been defined. In a multicenter study, we tested whether changes in the EEG and MLAER after a tetanic stimulus applied to the wrist could be used to predict subsequent movement in response to skin incision in patients anesthetized with 1 minimum alveolar anesthetic concentration (MAC) isoflurane in N2O. We also investigated whether the absolute values of any of these variables before skin incision was able to predict subsequent movement. After the induction of anesthesia with propofol and facilitation of tracheal intubation with succinylcholine, 82 patients received 1 MAC isoflurane (0.6%) in N2O 50% without an opioid or muscle relaxant. Spontaneous EEG and MLAER to auditory click-stimulation were recorded from a single frontoparietal electrode pair. MLAER were severely depressed at 1 MAC isoflurane. At least 20 min before skin incision, a 5-s tetanic stimulus was applied at the wrist, and the changes in EEG and MLAER were recorded. EEG and MLAER values were evaluated before and after skin incision for patients who did not move in response to tetanic stimulation. Twenty patients (24%) moved after tetanic stimulation. The changes in the EEG or MLAER variables were unable to predict which patients would move in response to skin incision. Preincision values were not different between patients who did and did not move in response to skin incision for any of the variables. MLAER amplitude increased after skin incision. We conclude that it is unlikely that linear EEG measures or MLAER variables can be of practical use in titrating isoflurane anesthesia to prevent movement in response to noxious stimulation. IMPLICATIONS: Reliable estimation of anesthetic adequacy remains a challenge. Changes in spontaneous or auditory evoked brain activity after a brief electrical stimulus at the wrist could not be used to predict whether anesthetized patients would subsequently move at the time of surgical incision.

Adolescent↗

Indocyanine green versus fluorescein angiography in the differential diagnosis of arteritic and nonarteritic anterior ischemic optic neuropathy.

PURPOSE: We evaluated in a prospective study the usefulness of indocyanine green (ICG) versus fluorescein angiography in the differential diagnosis between arteritic and nonarteritic anterior ischemic optic neuropathy (AION). METHODS: Simultaneous ICG and fluorescein angiography was performed on 22 eyes with AION. Appearance of both dyes in the choroid and in the retina, laminar flow, venous filling, and complete filling of the choroid were measured independently. Massive delayed choroidal filling corresponding to occluded posterior ciliary arteries was especially assessed, as it is almost always diagnostic of arteritic AION. We considered the choroidal filling as massive delayed if it was still incomplete after the venous filling. RESULTS: We diagnosed 5 arteritic AIONs, confirmed by biopsy, and 17 nonarteritic AIONs. In both types of angiography, 3 of 5 patients with arteritic AION showed massive delayed complete choroidal filling times (44.2, 45.8, and 70 seconds), and patients with nonarteritic AION had normal complete choroidal filling times. Dye appearance at the different angiographic times was similar for fluorescein and ICG angiography (P = 0.95-0.96). CONCLUSION: Fluorescein angiography alone is sufficient to reveal massive delayed choroidal filling time in arteritic AION. For our purpose, ICG angiography provides no additional information.

Aged↗

[Interdisciplinary evaluation for liver transplantation: the Bern concept].

Orthotopic liver transplantation (OLT) is the therapy of choice for a variety of end-stage liver diseases. The 5 year survival rate for electively operated patients with non malignant liver disease is exceeding 70%. Crucial for patient management is the early referral of the patient to a liver transplant center where an interdisciplinary evaluation of the patient is undertaken during a short hospital stay. The diagnosis will be confirmed, the operability assessed, contraindications excluded and the conservative treatment improved. A timely operation is of extreme importance and is based on an estimation of the severity and the dynamics of the liver disease. The liver transplantation should be performed early in a patient with a preserved liver function in order to achieve the best results.

Contraindications↗

[Electrophysiologic arousal reactions during sufentanil-/isoflurane anesthesia].

PURPOSE: There is controversy about relevant EEG signal changes indicating adequate or inadequate anaesthesia. Differences of drug-induced and nociceptive mediated signal changes have not been studied in detail. The present study investigates whether signal changes during decreases of depth of anaesthesia due to surgical stimulation depend on different isoflurane concentrations during sufentanil anaesthesia. METHODS: Following IRB approval and written informed consent 28 patients (ASA: I; age 43 +/- 11 y) scheduled for elective abdominal surgery were included in the study. Anaesthesia: propofol (2.0 mg/kg) and sufentanil (1.0 micrograms/kg). Following endotracheal intubation (vecuronium 0.1 mg/kg) patients were normoventilated (P(ET)CO2: 36-38 mmHg). Randomly assigned to steady-state anaesthesia (group 1: P(ET)Isoflurane 0.2%, (14n); group 2: P(ET)Isoflurane 0.6%, (14n) during the start of surgery. Monitoring: heart rate (HF), mean arterial blood pressure (MAP), P(ET)CO2, arterial oxygen saturation and rectal temperature. EEG (16 channels referenced to Cz; CATEEM, Medisyst, Linden) recorded 5 min before until 10 min after the start of surgery. EEG-analysis (FFT: 4s, 256/s, 0.45-35.0 Hz): topographical distribution of power spectral densities (delta, theta, alpha 1, and alpha 2). Artifact control: ECG and EOG. RESULTS: Surgical stimulation resulted in increases of MAP in both groups (p < 0.05 vs BL), whereas HR was only slightly affected in group 2 when compared with BL. Other variables except of EEG data did not change over time. In group 1 (0.2% isoflurane) surgical stimulation resulted in decreases of delta over the whole cortex (F2, C3, P3, O1) and in marked increases of alpha predominantly at central leads (C3)(p < 0.05 vs BL). In group 2 (0.6% isoflurane) nociceptive stimulation was associated with decreases of faster waves (alpha: F3)(p < 0.05 vs BL) and increases in delta at fronto-central areas (F3, C3)(p < 0.05 vs BL). CONCLUSIONS: EEG recordings are useful in assessing pharmacodynamic drug effects. In contrast, intraoperative EEG recordings have a low correlation to clinical signs of changes in the anaesthetic state. Previous studies demonstrate paradoxical EEG-arousal reactions during isoflurane anaesthesia. The present data suggest that classical or even paradoxical EEG arousal due to nociceptive stimulation may depend on the isoflurane concentration. It seems reasonable that the ascending reticular formation is functionally blocked by isoflurane in a dose-dependent manner.

Adult↗

[Digital internet-based ophthalmologic image databank].

OBJECTIVE: To manage an ophthalmological image database easily and rationally. MATERIALS AND METHODS: Fundus, macro and simultaneously recorded Fluorescein and ICG angiography images were digitized and archived using personal computers and UNIX workstations. Image data were written to CD-recordables. The CD-s with image information were stored in a jukebox-server. On demand image information was converted to dynamic hypertext markup language (html) with a WWW-server. Information stored on the servers could be observed with browser programs running on client computers connected to local area network. The communication with ophthalmologist working outside our hospital was realized by electronic mail. RESULTS: Different platforms (PC, Mac, workstations, etc.) and operating systems (Windows 3.x, 95, NT, MacOS, UNIX, etc.) can be used as clients. The communication with the system is accomplished by standard internet programs (Internet Explorer, Netscape Navigator, etc.). Thanks to the intuitive graphical user interface, no special computer knowledge is required to retrieve the stored data. CONCLUSION: Our digital image database has many advantages over a conventional image archive: it is round the clock available, images can be stored and copied without loss of quality, digital images can be easily integrated in other applications, it can be used without special computer knowledge, it is expandable and compatible with all contemporary computer platforms.

Computer Communication Networks↗

[Susac syndrome--a case report].

BACKGROUND: The Susac syndrome is often misdiagnosed as Multiple Sclerosis. In the absence of an early diagnosis of the disease, both the doctors and patients concerned are left in an uncertainly regarding the interpretation, diagnosis and prognosis of the discovered illness. PATIENT: The following case report focuses on this syndrome. CONCLUSION: The disease mainly affects young women and appears in the triple form of retinal arterial occlusion, hearing impairment and Encephalopathy.

Adult↗

Quantitative topographical electroencephalographic analysis after intravenous clonidine in healthy male volunteers.

UNLABELLED: We used quantitative topographical electroencephalography (EEG) to determine the time course of changes in brain electrical activity after clonidine infusion. Twenty healthy male volunteers (aged 24 +/- 5 yr) were included in the randomized, double-blind, placebo-controlled (Group 1, placebo, n = 10; Group 2, 2.0 micrograms/kg clonidine, n = 10) study. EEG (17 electrodes, common average reference, fast Fourier transformation, band pass 0.4-35.0 Hz) output was recorded until 145 min after drug infusion. Subjects were intermittently stimulated by verbal commands. Clonidine-related changes resulted in attenuation of the physiological alpha fluctuations seen in untreated subjects and were most pronounced at parietooccipital (P4, O2) recording sites. This was associated with initial maximal increases in slow wave activity (delta) almost uniformly distributed over the whole cortex, restricting with time to occipital regions (O2). The EEG mapping technique may provide more specific information about clonidine-mediated sedative effects, indicating facilitations of EEG patterns that are not homogeneously distributed. These EEG changes cannot be explained by physiologic changes in vigilance or by normal sleep stages because they were not observed after placebo. EEG effects seem to be unrelated to changes in hemodynamics. IMPLICATIONS: In healthy volunteers, placebo-controlled signal changes in the electroencephalogram were evaluated to quantify sedative drug effects after intravenous application of clonidine. A multichannel recording system and electroencephalogram mapping technique indicate fluctuations of electroencephalogram patterns that are not homogeneously distributed over the cortex associated with sedation.

Adrenergic alpha-Agonists↗

[Effect of remifentanil on clinical and electroencephalographic parameters of depth of anesthesia in balanced anesthesia with propofol, enflurane or isoflurane].

UNLABELLED: Electrophysiological parameters are well-suited to detect changes in cerebral function. The present study investigates whether balanced anaesthesia with remifentanil during nociceptive stimulation is associated with changes in clinical and electrophysiological parameters indicating inadequate depth of anaesthesia. Following IRB approval and written informed consent, 23 patients (ASA: I; age: 36 +/- 11) scheduled for elective gynaecological laparoscopy were included in the study. Without any premedication, anaesthesia was induced with remifentanil (1.0 microgram/kg bolus injection), propofol (0.5 mg/kg added by repetitive (10 mg) bolus injections every 10 s until unconciousness) and vecuronium (0.1 mg/kg). Following endotracheal intubation (normoventilation: PetCO2: 36 bis 38 mmHg), remifentanil infusion was started with continuous doses of 0.5 microgram/kg/min over 5 minutes and maintained with 0.25 microgram/kg/min during surgery. Remifentanil was randomly combined with propofol (group 1: 100 micrograms/kg/min; n = 7), enflurane (group 2: 0.5 MAC; n = 8) or isoflurane (group 3: 0.5 MAC; n = 8). Monitoring included: heart rate (beats/min), mean arterial pressure (mmHg), oxygen saturation (%), endtidal CO2 (mmHg) and endtidal enflurane and isoflurane (%). EEG: 2-channel recordings of Fz versus mastoid and ECG (artefact control) during steady-state anaesthesia and surgery. Following fast-fourier-transformation (4 s; 256/s; 0.5 to 35.0 Hz), spectral power densities were calculated for the selected frequency bands. Auditory evoked potentials (AEP; middle latency) were registered simultaneously after binaural stimulation via head-phones click-stimulation (6 Hz; 75 dB above hearing threshold; 512 stimulations per average). Bandpass was 0.01 to 2.0 kHz. ANALYSIS: Na, Pa, Nb (latencies; ms) and peak-to-peak amplitudes (NaPa, PaNb; microV). EEG and AEP recording technique [15]. The study protocol included baseline values from pre-intubation, pre-surgery, the respective post-stimulation values (1 min, 3 min, 5 min) and all data at five-minute intervals during surgery until emergence from anaesthesia. During steady-state study conditions with defined remifentanil applications, mean data indicate that in response to nociceptive stimuli no changes in clinical or electrophysiological parameters were observed. In contrast to other studies using different anaesthetic techniques, the present data from remifentanil indicate very stable haemodynamic and electrophysiological parameters (EEG, AEP) during noxious stimulations. Adjustable and with no plasma accumulation, remifentanil demonstrates potent antinociceptive effects resulting in signs of adequate anaesthesia.

Adult↗

The significance of shed membrane particles during programmed cell death in vitro, and in vivo, in HIV-1 infection.

The plasma membrane remodeling, including the early transverse redistribution of phosphatidylserine, is a general feature occurring in cells in which a death program has been induced. In most cases, studies of this kind have focused mainly on cells. In this study, we report a clear correlation between the degree of apoptosis induced by a variety of agents in several types of cultured cells and the amount of shed membrane microparticles captured in the corresponding supernatants by insolubilized annexin V, a protein showing a strong affinity for phosphatidylserine. Such particles carry membrane antigens specific of the cells they stem from, and through which capture is also feasible. Homologous circulating microparticles were captured in peripheral blood from individuals with HIV-1 infection. A substantial proportion bore CD4 antigen. In some cases, CD4+ particles could be detected even in the absence of circulating CD4+ T cells, testifying to the presence of such resident cells in lymphoid tissues. These results suggest that shed membrane particles are one of the hallmarks of programmed cell death, of particular interest when the corresponding cells are hardly accessible.

Acquired Immunodeficiency Syndrome↗

Safety of a new transpulmonary echocontrast agent (Albunex) in repeated echocardiographic studies in patients.

BACKGROUND AND HYPOTHESIS: Multiple contrast-enhanced echocardiographic studies are to be expected in patients with cardiac ischemic disease, but the sonication process used to produce the echocontrast agent Albunex may result in new epitopes that could cause an immunogenic response. METHODS: Repeated exposures to intravenous Albunex over a period of time long enough to allow development of an eventual immune reaction were performed in 12 patients while monitoring for lymphocyte transformation, microsphere specific IgE and IgG antibodies, and systemic, pulmonary artery, capillary wedge, and right atrial pressures, as well as cardiac output, left ventricular fractional shortening, and blood gases. RESULTS: No significant 3H-thymidine incorporation and thus no specific blastic transformation of the patients' lymphocytes were observed either for high or low Albunex concentrations, corresponding to the expected hepatic and plasma concentrations of microspheres. No formation of microsphere-specific IgE and IgG antibodies was observed after the first or second Albunex exposure. Furthermore, no clinically significant hemodynamic or respiratory adverse reactions were observed in any patient. CONCLUSION: These results suggest that repeated exposures to intravenous Albunex induce no adverse effect on the cellular and humoral immune systems and on left and right heart hemodynamics in patients.

Albumins↗

Low dose radiation for subfoveal choroidal neovascularization in age-related macular degeneration. A pilot study: radiotherapy for age-related macular degeneration.

The aim of our pilot study was to test the effect of low dose radiation on classic and occult subfoveal choroidal neovascularization (CNV) in age-related macular degeneration (AMD). The posterior pole of the afflicted eye of 12 patients was irradiated with 5 Gray (Gy), and that of 34 patients with 8 Gy. The radiotherapy was done by a linear accelerator (6 MV X-rays) during 4 consecutive days with daily doses of 1.25 Gy and 2 Gy respectively. At the time of treatment, and 6 weeks, 6 months and 1 year after, a simultaneous fluorescein and ICG angiography of both eyes were carried out, and the distance visual acuity was measured. In none of the cases were we able to note a reduction in the subfoveal membrane's size. With regards to the visual acuity, the evolution was slightly better than the spontaneous courses described in existing literature. Further prospective randomized studies with higher dose radiation are necessary in order to determine the significance of radiotherapy in the treatment of this pathology.

Aged↗