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Allergic granulomatosis accompanied by angiitis (Churg-Strauss syndrome) constitutes an unusual disorder which is characterized clinically by bronchial asthma and hypereosinophilia, accompanied by systemic symptoms of histopathologically and by necrotizing vasculitis, extravascular granulomas and tissue infiltration by eosinophils. We report a case of a 4 year-old child presenting with acute pneumonia and deteriorated general condition. The biopsy of an inflammatory pseudotumor of the right anterior orbit revealed necrotizing vasculitis, extravascular epitheloid granuloma and eosinophilic tissue infiltration. These are characteristic changes of allergic granulomatous vasculitis (Churg-Strauss syndrome. Laboratory findings were characterized by blood eosinophilia, increased IgE value and the presence of antineutrophil cytoplasmic ant antibodies (p-ANCA). Local and systemic manifestations quickly regressed after parenteral application of corticosteroids. Two exacerbations of inflammatory pseudotumor occurred after reduction of the corticosteroid dosage. Systemic vasculitic syndromes are rare in childhood. Orbital manifestations in Churg-Strauss syndrome in childhood have never been reported.

Slitlamp observations of the position of the ciliary body behind the iris root are possible only in cases of gross anatomic, and probably also functional, abnormalities. This study was performed to investigate physiological changes of the human ciliary body configuration during accommodation.We used the 50 MHz ultrasound biomicroscope to measure the ciliary body changes in 5 left eyes of normal subjects during accommodation, while the right eye, wearing corrective spectacles, focussed Snellen letters at a distance of 3 m. For desaccommodation plus lenses were utilized, while negative lenses were applied to blur vision as a stimulus for accommodation. During postprocessing the best images of the video sequence were recalled on a monitor and the profile of the ciliary body was manually drawn on a transparent folder. For interpretation we used a projection system with vector analysis.During accommodation there is a shift of the ciliary body anteriorly toward the scleral spur and in the direction of the lens equator. In 4 out of 5 eyes a contact between the ciliary body and the posterior iris surface could be demonstrated. There was a measurably widening of the anterior chamber angle in 3 out of 5 eyes.Ultrasoundbiomicroscopy seems to be a way for assessing ciliary body deformation during accommodation. Our results are in accordance with histologic and gonioscopic findings and confirm biomechanical theories of the accommodation process. Further investigations including online digital image processing will be necessary to evaluate accommodation in its complexity.

There is little information about the state of human keratocytes in longterm cornea storage and the influence of these cells on the survival of the corneal transplant after keratoplasty. Up to now stromal keratocytes have not been taken into consideration in regard to the culture conditions in cornea banking. Therefore, a method was used, first described by Poole et al., who stained porcine corneas using the Live/Dead-Assay (Molecular Probes Inc.). After staining porcine and human corneal slices with the fluorogenic substance calcein AM and the fluorochrome ethidium homodimer, we examined the fluorescing cells to acquire more knowledge about the density, morphology and vitality of human keratocytes. Living cells are distinguished by the presence of ubiquitous intracellular esterase activity, determined by the enzymatic conversion of the virtually non-fluorescent cell-permeant calcein AM to the intensely fluorescent calcein, producing an intense, uniform, green fluorescence in living cells. Ethidium homodimer enters cells with damaged membranes and undergoes a 40-fold enhancement of fluorescence on binding nucleic acids, thereby producing a bright red fluorescence in dead cells. The examinations were performed using a conventional fluorescence microscope and a confocal slit scanning microscope. Like in the porcine corneas, we found three keratocyte subpopulations in the human corneas, but there were some differences in morphology and patterns of staining between the two species in the central and posterior stroma. After long periods of cornea storage we found signs of cell degeneration like loss of cytoplasmic processes and an increasing number of dead cells.(ABSTRACT TRUNCATED AT 250 WORDS)

The coding of ophthalmological diagnoses is a long-standing problem that has recently been highlighted by the planned introduction of ICD 10.Using an alphanumerical classification system for the first time, ICD 10 offers the space needed for necessary expansion without leading once again to dislocations in the numbering system. The FoxPro 2.5 database system was used to create a program based on an expanded ICD 10 that can be applied from DOS and Windows.ICD 10 was expanded by the addition of a numerical fifth digit, thus increasing the number of classifiable ophthalmological disorders by a factor of 4.2 from 390 to 1635. The new program greatly facilitates the handling of this substantial amount of data.The enhanced diagnosis coding achieved with the expanded ICD 10 permits nosologically exact statistics to be kept for use as a basis for further scientific work.

An orbital implant after enucleation compensates for volume deficiency and increases prosthesis motility. In the literature, however, an extrusion rate of orbital implant between 10 and 25% is reported. Since the introduction of hydroxylapatic ceramics (HAC), these numbers have been reduced considerably. The HAC, which is derived from corals, has a rough surface and requires a scleral covering for implantation. The HAC, which is made in the laboratory, can be produced with smoother surfaces, so that a homoplastic covering is no longer mandatory. A composite implant was developed to improve prosthesis motility further. This consists of artificial HAC at its anterior surface to guarantee safe tissue integration; the posterior part of the implant is manufactured from silicon rubber to create a jointlike structure in Tenon's capsule. Integration of the porous HAC in the orbital soft tissues has been tested and confirmed by animal experiments. After 30 full HAC implants and 25 composite implants, only one extrusion occurred. In all other cases, compatibility proved to be excellent; transmission of the motility to the prosthesis was moderate to good. Examinations comparing prosthesis motility and computer tomographically evaluated implant motility enabled the analysis of deficits in motility transmission of the implant for the artificial eye.

In patients with a reduction in visual function because of optic nerve neuritis, light sensitivity is tested to detect differences between the right and left eye in combination with the swinging flashlight test and visual evoked potential (VEP). A binocular Zeiss microscope was modified to use integrated photometer-controlled binocular stimulus fields and a central light system for fixation and variation of the contrast (background illumination). For exact binocular measurements of light sensitivity on both eyes, electronically controlled test fields (visual angle 5 degrees-20 degrees) guarantees only macular or overfoveolar stimulation. In addition, splitting the light for each stimulus field from only one halogen lamp guarantees wave-length-independent testing. Patients with various retinal diseases and neuritis nervi optici pathology were examined using pattern VEP, testing of the absolute lower threshold of light sensitivity, and binocular comparison over the range of luminous density. This binocular optical photometer system allowed minimal differences to be identified in the present visual function and after the eye had recovered from optic nerve neuritis.

Eine Moglichkeit der Korrektur einer hohen Myopie am linsenhaltigen Auge stellt die Implantation einer retropupillaren, flexiblen Intraokularlinse dar. Die Beziehung zwischen Linsenhaptik und umgebenden Bulbusstrukturen last sich mit herkommlichen Untersuchungsmethoden postoperativ nicht erfassen. Wir haben daher Untersuchungen mit Hilfe der Ultraschallbiomikroskopie durchgefuhrt, um die Lage und das Zentrierungsverhalten dieser Implantate zu erfassen. Insgesamt zehn dieser Myopielinsen wurden in menschliche Leichenaugen implantiert und anschliesend vermessen. Desweiteren konnten wir eine Patientin drei Jahre nach komplikationsloser Implantation dieser epilentikularen Myopielinsen untersuchen.

Ultrasound biomicroscopy (UBM) allows high-resolution imaging of the anterior segment due to ultrasound transducers between 50 and 100 MHz. At present stage of experience, mainly analysis of iris and ciliary body structures seem to be clinically rewarding. This is demonstrated by two similar looking tumors, involving the chamber angle. By means of UBM it was possible to differentiate between cystic and solid growths and to assess tumor extensions.

We reviewed 184 cases of uveal melanoma treated with 106Ru eye plaques. The influences of the dose rate, the total dose and the initial tumour size on the incidence of metastases were of major interest in this retrospective analysis. It is widely accepted that the risk of metastatic spread increases with increasing tumour volume. However, for tumours measuring10 mm in basal diameter the dose rate in brachytherapy with 106Ru eye plaques might be important, since we observed a better prognosis for patients treated with plaques of relatively low activity.

Mit Hilfe eines Finite-Elemente (FE)-Modells wurden die mechanischen Wechselwirkungen der Implantation von Intraokularlinsen (IOL) in den Kapselsack berechnet. Die Wechselwirkung von IOL-Kapselsack und dessen Beanspruchung wird mit speziellen Kriterien beschrieben.

Das Ultraschallbiomikroskop ist ein Hochfrequenzultraschallgerat mit einem Auflosungsvermogen bis 50 µm. Es ermoglicht, Strukturen der vorderen Augenabschnitte differenziert darzustellen. Intraokularlinsen sind hoch reflektierende Substanzen, die mittels Ultraschall gut abgrenzbar sind. Wir untersuchten die Lage der Linsenoptik und -haptik. Eine gute Dokumentation der Lokalisation einer Kunstlinse ist moglich. Die exakte Zuordnung der Haptik zum Ziliarkorper gelingt nicht immer. Eine routinemasige Untersuchung von Hinterkammerlinsenimplantaten erscheint momentan nicht sinnvoll.

Neurofibromatosis (NF) is one of the most frequent autosomal-dominant hereditary disorders. The molecular-genetic differentiation of NF 1 and NF 2 has important implications for the ophthalmologist. Among 80 patients with NF 1, Lisch nodules were diagnosed in 83% as typical criteria for the disease. In 6 patients who did not meet the NIH criteria for NF 1 and NF 2, the ophthalmological investigation showed no cataracts or Lisch nodules; thus, the ophthalmological examination can help to confirm a subtype of NF. In 8 out of 22 NF 2 patients a juvenile posterior subcapsular cataract was diagnosed. Our examination demonstrates that the diagnostic value of lens opacities in NF 2 patients--especially for early detection of the disease--must be clarified, especially with regard to the fact that there were no patients with incipient cataract and no neuroradiological criteria for the disease.

The influence of the dose-rate on tumor response in radiotherapy with 106-Ruthenium eye plaques has been investigated in an experimental tumor system.The identical total dose was applied within three different overall treatment times (42 hr, 192 hr and 312 hr), corresponding to dose-rates of 6.0 Gy/hr, 1.3 Gy/hr and 0.8 Gy/hr.The therapeutic outcome of brachytherapy varied significantly between the three groups of animals treated with different dose-rates. At a dose-rate of 1.3 Gy/hr all tumors were locally controlled, but no local control was observed when a dose-rate of 6.0 Gy/hr was delivered. 0.8 Gy/hr was less effective than 1.3 Gy/hr but more effective than 6.0 Gy/hr.These results were unexpected but they might be explained by an incomplete reoxygenation if the overall treatment time is too short (42 hr, dose-rate 6.0 Gy/hr) and by proliferation of tumor cells under treatment if the overall treatment time is too long (312 hr, 0.8 Gy/hr).

In detachment surgery after a mechanically stabile chorioretinal scar is at present full scleral indentation no longer mandatory. Following these considerations absorbable scleral implants have been developed and tested in an animal model. Cylindrical pieces of absorbable composite-material with a diameter of 5 mm were sutured as radial scleral explants in 18 rabbits. The composite material consisted of a polyglactin-polydioxanon ratio 7:1. The absorption time for polyglactin is 60 days, for polydioxanon 180 days. The explants produced initially in ultrasonographically measured buckle height between 3.2 and 4.0 mm. The clinical and ultrasonographical follow up study demonstrated a continuous decrease of buckle height. Two weeks after implantation there was a medium height of 2.0 mm after five weeks a medium elevation of 0.5 mm was found. Histopathological examinations showed incidence of a slight resorptive inflammation in the area of the buckle which was not evident after 12 weeks. No scleral infiltration or scleral thinning was found. The promising results have justified controlled clinical trials with the absorbable material which might allow to combine the advantages of silicone sponge explants (precise localization) with those of scleral buckles by inflatible balloons (reversibility).

Intraokularlinsen mit zirkularer Haptik sollen die gleichmasige kreisformige Kapselsackausspannung zur Verhinderung von Dezentrierung und Tilting garantieren. Hier wurden 2 unter dieser Zielsetzung konstruierte Intraokularlinsen einer konventionellen Linse mit Zweipunkthaptik gegenubergestellt. In den dynamometrischen Messungen wurden alle 3 Haptiken radiar und sagittal komprimiert und die entstehenden Ruckstellkrafte gemessen. In der radiaren Messung ergaben sich die kleinsten Kraftdifferenzen entlang der Mespunkte an der auseren Zirkumferenz bei der neuen Zirkularhaptik-Linse. In den ersten klinischen Beobachtungen ist eine geringe Dezentrierungsrate zu verzeichnen. Die dynamometrisch ermittelten Ruckstellkrafte nach Sagittalkompression am auseren Haptikbugel sind bei diesem Linsenmodell zirkular gleichformig niedrig. Ob die spezielle Hochkantprofilie-rung der Haptikbugel und die damit gewonnene Torsionssteifigkeit klinisch die Haufigkeit des Tiltings signifikant senken kann, bleibt weiteren Untersuchungen vorbehalten.

Nach Elastizitatsmessungen des von Kern und Rindenmassen gereinigten menschlichen Kapselsacks wird ein Modell aus Siliconkautschuk entwickelt, das es erlaubt, vergleichende Untersuchungen zur Verformung verschiedener Intraokularlinsentypen durchzufuhren. Durch die Angabe eines Verformungsquotienten, gebildet aus dem grosten und kleinsten Kapselsackmodelldurchmeser, ist es moglich, durch einen Meswert eine Aussage uber die Anpassungsfahigkeit eines Kunstlinsenmodells an den menschlichen Kapselsack zu machen. Die Werte schwanken zwischen lâsso und lâsso 92, wobei sowohl Haptikgeometrie als auch Haptikmaterial den Verformungsquotienten beeinflussen.

73 verschiedene Intraokularlinsen mit konventioneller offener oder geschlossener Haptik wurden in Kapselsackmodelle mit den Durchmessern 8,5 mm, 9,5 mm und 10,5 mm implantiert. Die biomechanischen Eigenschaften dieser aus Silikonkautschukmembranen hergestellten Modelle entsprechen weitgehend einem durch Rhexis eroffneten, von Kern und Rinde gereinigtem menschlichen Kapselsack, der noch im Zonulaapparat verankert ist.

An experimental setting is presented to evaluate the endothelial protection offered by various viscoelastic materials applied in cataract surgery. The substances used were: hydroxypropylmethylcellulosis, a hyaluronic acid preparation (molecular weight 5.10(6), concentration 10 mg/ml), a hyaluronic acid preparation (molecular weight 800 000, concentration: 35 mg/ml), and balanced salt solution as control. The endothelial surface of pig corneas were covered by test substances and spread with a loop of prolene 4.0 suture material in a mechanically standard way. A total of 40 corneas were examined and the amount of endothelial damage evaluated by photometry using Janus-green wash-out, a substance, which selectively binds to damaged endothelial cells or descement membrane. The damaged surfaces differed significantly in all groups of viscoelastic substances and in the control group. Examination showed that the least damage was in group 3, followed by group 1 and the most damage in group 2. Endothelial protection during cataract surgery can be improved by modifications of the substances presently applied.

We report this exemplary case of a drug addict with candida endophthalmitis where we used the new form of amphotericin B, encapsulated in liposomes. We were able to reconfirm the reduced number of side effects and the minimized nephrotoxicity reported by authors of other specialties. In our patient, a reduction or elimination of the yeast was probably achieved, nevertheless, he developed a traction retinal detachment. In future cases of fungal endophthalmitis, we recommend liposomal amphotericin B in higher doses.

A randomized retrospective study concerning survival of Ruthenium treatment and enucleation in melanoma patients has been performed. For 112 patients from Hamburg who underwent Ruthenium therapy individual match partners were selected in Copenhagen where during the same period of time enucleation was the standard procedure. Selection took place concerning patient's age and sex at the time of treatment, initial tumor volume and the time of treatment. The present status of the patients was not known during the selection process. During the observation time of 12 years there was a survival rate after irradiation of 77.9% and after enucleation of 78.6%. Cox' regression disclosed a coefficient of 0.049 with a standard aviation of 0.293 and a P-value of 0.867. All parameters were showing no statistical difference between Ruthenium treated and enucleated patients. The survival rate in males was 69.2%, female patients 87.2%. For male patients there was a 2,4-fold higher risk to develop metastasis compared with female patients. Patient's age at the time of treatment correlated significantly with the prognosis. There was an increase in mortality risk by factor 1.4 per decade.

Microsurgical removal of a large congenital orbital teratoma is reported with successful preservation of visual function. The importance of interdisciplinary work-up including neuroradiology, ophthalmology, maxillo-facial surgery and histopathology is demonstrated. During the postoperative period closed follow-up to control refraction and to treat amblyopia is mandatory to gain optimal results.

In three prospectively randomized groups of patients viscoelastic materials during IOL-implantation have been compared concerning 1. intraocular pressure, 2. endothelial cell count, 3. corneal thickness. Examinations were performed preoperatively, the first, second and fifth postoperative day. There was no statistical difference between hydroxypropylmethylcellulose (2%), hyaluronic acid (1%) and air. Examinations were performed preoperatively the first, the second and the fifth postoperative day. There was no statistically significant difference between all groups of patients, Advantages and disadvantages for routine use of viscoelastic substances are discussed.

In spite of modern optical examination techniques such as sonography, nuclear magnetic resonance tomography (NMR) and x-ray computer tomography up to now the meningioma of the optic nerve sheath still poses a problem in respect of differential diagnosis. This problem is illustrated by two case reports. In both patients a meningioma of the optic nerve sheath could be diagnosed only after various attempts using all the imaging techniques mentioned above. NMR in combination with Gadolinium injection gave most important information.

B-scan guided pulsed Doppler ultrasonography was applied in 62 patients with unilateral malignant melanoma. Prior to radiotherapy Doppler frequency shifts were detected in all but one neoplasm. The average systolic tumour blood flow velocity was recorded as 18.8 +/- 7.6 cm/s. Frequency shifts after radiotherapy are described. Probably the methods will find a place in the evaluation of indeterminate fundus lesions and in the follow-up of irradiated ocular melanomas.

Doppler shifts were detected using duplex and color Doppler scanning in 41 of 42 patients with malignant melanomas of the uvea. Mean maximum tumor systolic velocity was 18.8 +/- 7.6 cm/s. Time-averaged maximum velocity in the tumor vessels was 12.3 +/- 5.3 cm/s. Maximum tumor velocity increased in four of eight tumors and was unchanged or had diminished in the other four 2 to 3 days after ruthenium plaque irradiation. Doppler shifts were undetectable in three tumors, markedly reduced in three tumors, and unchanged in one tumor 1 to 4 months after treatment. We detected minimal non-pulse-synchronized Doppler shifts in one of three tumors, and no shifts in the remaining two tumors 1 1/2 to 4 years after therapy. Color duplex scanning allowed a rapid overview of tumor vasculature and facilitated study of individual vessels.

The authors followed the clinical course of two patients with osteoma of the posterior pole for a period of two years. A 60 year old male patient whose bone formation was confined to the episclera remained asymptomatic during the follow-up period. In contrast, the visual acuity of a 9 year old female patient with an osteoma of the choroid fell from 1.0 (20/20, 6/6) initially to 0.2 (20/100, 6/30) during the same two year follow-up interval. After reviewing the literature, the authors consider the pathophysiological prerequisites for ocular bone formation and discuss the differential diagnostic possibilities.

The influence of the dose-rate of 106Ru-plaques on tumor response was investigated in an experimental tumor-host system (rhabdomyosarcome R1H of the rat). A highly significant difference in tumor response was observed between tumors treated with the identical total dose (25 Gy) but varying dose rates (1.3 Gy/h vs 6.0 Gy/h). All tumors treated with the low-dose irradiation were locally controlled, whereas only one local tumor was controlled by higher dose irradiation. These unexpected results may be explained by the short overall treatment time with high dose rates, which does not allow sufficient reoxygenation of hypoxic tumor cells. In addition to the total dose, the dose rate should be included in treatment planning for choroidal melanoma brachytherapy, and analysis of the clinical data on this topic seems to be necessary in order to develop new therapy concepts.

By employing the so-called inversion recovery technique, one has a nuclear magnetic resonance method at hand that allow discrete imaging of lesion in the intraorbital portion of the optic nerve in patients with optic neuritis. In our series, signal rich areas were visible in affected optic nerves in 15 of 18 patients. The areas of increased signal intensity involved the middle or the proximal third of the nerve and were still demonstrable following recovery of visual function. On the other hand, inversion recovery studies of the affected optic nerves following long inflammation free periods after an attack were within normal limits. Inflammatory edema or alterations in glial tissue may be considered as the causes of the increased signals.

Anhand des sogenannten Kontrast-Sensitivitats-Tests nach Ginsburg wurde das Kontrastsehen von Tragern diffraktiver IOL mit dem Kontrastsehen von Tragern monofokaler IOL verglichen. Zudem wurde versucht, Dammerungssehen und Blendungs-empfindlichkeit am gleichen Patientengut mit dem Rodenstock-Nyktometer zu bestimmen. Das Nyktometer stellte sich jedoch wegen seiner zu geringen Kontraste und der zu hohen angebotenen Blendung fur eine Untersuchung an Tragern intraokularer Linsen als ungeeignet heraus. Der Kontrast-Sensitivitats-Test nach Ginsburg zeigte deutlich besseres Kontrastsehen der Trager monofokaler IOL. Daher sollte insbesondere bei Patienten aus bestimmten Berufsgruppen vor der Implantation einer diffraktiven IOL sorgfaltig abgewogen werden, ob diese physikalisch-optische Eigenschaft fur den jeweiligen Patienten nicht eine Einbuse der postoperativ angestrebten visuellen Qualitat bedeutet.

Bei 48 Patienten wurden 50 diffraktive Intraokularlinsen (3M Typ P751E) implantiert (mittleres Patientenalter 71 Jahre). Nach einer mittleren Nachbeobachtungszeit von 7,5 Monaten wurden die Sehscharfen in 5, 3 und 1 m und in 40 cm mit bester Fernkorrektur und ohne Korrektur bestimmt. 35 Patienten wunschten eine Fernkorrektur. Danach betrug die mittlere notwendige Korrektur −0,7 dpt. sph= −1,25 cyl. 12 Patienten benotigten die Fernkorrektur zum Lesen, 8 Patienten waren auf eine Bifokalbrille angewiesen. Es bestand kein Zusammenhang zwischen der Fahigkeit beide Foci auszunutzen und der Dezen-trierung der Linse (bis 1 mm bei 7 Patienten, bis 1,5 mm bei 2 Patienten). 39 Patienten waren mit dem Visusergebnis zufrieden. Auf Befragen wurden folgende Sehstorungen geausert: Auffallige Sehminderung in der Dammerung (12), Ringe um Lichtquellen (8), starke Blendung (5), Unsicherheit beim Treppenlaufen (5), gelegentlich Kopfschmerzen und Doppelbilder (4). Der Anteil der Patienten, der im Alltag auf die Brille verzichten konnte, war gering. Eine Uberlegenheit diffraktiver multifokaler Linsen gegenuber monofokalen scheint z. Z. noch nicht belegbar. Endgultige Empfehlungen sind noch nicht zu geben, weitere kontrollierte Studien notwendig.

Die mechanische Stabilitat des von Kern- und Rindenmassen gereinigten Kapselsacks wird wesentlich von der Beschaffenheit der Kapsulotomierander bestimmt. Bei der „Dosenoffnertechnik“ entstehen zwangslaufig multiple, radiar gerichtete Einrisse in der vorderen Linsenkapsel, die bei Belastung in den Kapselsackaquator und daruber hinaus in die Hinterkapsel hinein weiterreisen konnen.

Bezuglich der makrofotografischen und histologischen Beurteilung eines neuen Kunstlinsen-Designs im Rahmen einer tierexperimentellen Studie werden folgende Schlusse gezogen: Die Qualitat der Makrofotografie ist deutlich besser nach koronarer Bulbuseroffnung. Die Kunstlinsen in pigmentierten Augen lassen sich makrofotografisch gut im Auflicht dokumentieren. Albino-Augen machen eine spezielle diaphanoskopische Technik notig. Gut beurteilt werden konnen hierbei: Kunstlinsenform und grose, Sitz der Kunstlinse in Relation zum Kapselsackaquator, Verkippung der Linse, Deformierung der Linsenhaptik, Verlagerung der Linsenhaptik gegenuber der Linsenoptik, Ausmas von Kortexresten, Lokalisation des Nachstars, Synechien, sog. „Iris capture“, Iris-tuck-Phanomen. Die sog. „Spaltlampenansicht“ kann bei weichen Kunstlinsenmaterialien eine hilfreiche Erganzung darstellen bezuglich Synechierungsverlauf, Verkippung der Linse und Verhaltnis der Kunstlinse zum Kapselsack. Die sagittale Bulbuseroffnung stellt fur die anschliesende histologische Untersuchung die besseren Voraussetzungen dar und sollte daher im Zweifel bevorzugt werden. Im histologischen Schnitt lassen gunstigenfalls Abdrucke und Gewebsaussparungen auf den ehemaligen Sitz von Kunstlinsenoptik und haptik schliesen, da sich sowohl PMMA- als auch Silikonlinsen beim Durchbringen durch eine Alkoholreihe komplett auflosen. Histologisch gut beurteilbar sind: Entzundungsreaktionen und sonstige Alterationen von Hornhaut, Kammerwinkel, Iris, Ziliarkorper und Kapselsack, Ausmas und Lage des Nachstars sowie der verbliebenen Kortexreste und Synechien.

Bei bisherigen Untersuchungen von Schadenmustern auf Intraokularlinsenmaterialien nach Nd-YAG-Laserbeschus konzentrierten sich die Autoren auf die Beschreibung und Quantifizierung von Oberflachenveranderungen. In dieser Untersuchung wurde die Erfassung der raumlichen Ausdehnung der Schaden in PMMA (Spritzgusverfahren) und Silikonkautschuk (Hochtemperaturvulkanisation) versucht. Die Schadenserfassung erfolgt lupenmikroskopisch durch die Schnittkante der Pruflinge. Die Dichte, die zur Auslosung eines Schadens ausreicht, liegt bei PMMA geringfugig hoher als bei Silikonkautschuk (1,8 mJ Leistung fuhrten bei PMMA in 90%, bei Silikonkautschuk in 96% zu sichtbaren Schaden). Der frontale Durchmesser der Schaden im Material betrug bei PMMA ca. 300 µ, bei Silikonkautschuk 30 µ. Fur die Klinik last sich daraus folgern, das Y AG-Lasereffekte im Silikon bei kleiner frontaler Ausdehnung geringere Streulichtquellen darstellen als die schneeflockenahnlichen Trubungsformen in PMMA-Materialien.

Uber das Formerinnerungsvermogen verschiedener Haptikmaterialien ist in der Literatur Gegensatzliches berichtet worden. Zur Klarung dieser Frage wurden Kunstlinsen mit PP-Bugeln und PMMA-Bugeln identischer Geometrie gegenubergestellt. Sie wurden bis zu 12 Monate in zylindrischen Behaltnissen mit einem Innendurchmesser von 11 mm eingespannt. Der unbeeinfluste Ausendurchmesser der Implantate betrug 14,0 mm. Zu unterschiedlichen Zeitpunkten wurden die Bugeldurchmesser im entspannten Zustand vermessen und die Ruckstellkrafte mit einem elektronischen Dynamometer bestimmt. Die PMMA-Schlaufen zeigten ein geringfugig besseres Formerinnerungsvermogen und erzeugten bei identischer Verformung grosere Ruckstellkrafte als Polypropylene-Haptiken. Der Einflus der Geometrie — es wurden jeweils C- und J-Schlingen beider Materialien verglichen — erwies sich als starker als die Materialeigenschaften. Fur die Biomechanik der Kunstlinse kommt danach der Formgebung eine grosere Bedeutung als den Materialeigenschaften zu.

Inversion recovery sequences with short inversion periods (STIR sequences) are particularly suitable for the examination of the intra-orbital and intracanalicular portion of the optic nerve, since they selectively suppress interference from neighbouring fat. This technique makes possible direct demonstration of retrobulbar neuritis that had to be diagnosed exclusively by clinical criteria up to now. As evidence of inflammatory changes in 15 out of 18 patients with acute retrobulbar neuritis, there were areas of increased signal intensity in the affected nerve; in six cases the nerve was also swollen. In eight normals and five patients with healed retrobulbar neuritis, the signal and calibre of the optic nerves were normal.

The relations between the deformation and resulting resilience of lens haptics with various geometries and made of different materials were studied. While there are no fundamental differences between PMMA and PP haptics with identical geometries, the resilience of soft lenses made of poly-HEMA and silicone rubber subjected to the same deformation is significantly higher. On the basis of such measurements it is possible to estimate stress on the capsular bag during and after implantation. In light of recent publications concerning the prevention of secondary cataract, permanent circular tensioning of the lens capsule appears a desirable goal. This requirement is best satisfied with a material with permanently high elasticity, which tensions the equator of the capsular bag over 360 degrees.

Von insgesamt funf Weichlinsentypen, zum Teil auf dem Markt erhaltlich, zum Teil als experimentelle Prototypen, wurde die Verformung der Haptikschlaufen unter der Belastung von 0,5 N gemessen. Die Untersuchungen erfolgten an einem elektronischen Dynamometer, die Fixierung der Linsen war durch eine Vakuumhalterung sichergestellt. Die Verformung der Weichlinsen lag zwischen 0,05 und 2,5 mm, die Auslenkung konventioneller J- und C-Schlingen zwischen 2,7 und 3,8 mm. Daraus wird abgeleitet, das der bei den Weichlinsen sehr viel grosere Haptikquerschnitt fur den vergleichsweise starren Halteapparat verantwortlich ist. Im Hinblick auf diese Ergebnisse ist eine besonders gute Anpassung der Linsengeometrie an den Implantationsort auch im nichtkomprimierten Zustand zu fordern.

Macroscopic appearance of the schwannomas is often found by echography (5 on 11 cases: 45% of the patients). As a correlate, we can assume that confronted with an extraconal and/or dumb-bell lesion with cystic spaces, the first diagnosis to think of is that of orbital schwannoma. Differentiation with malignant peripheral nerve sheath tumor is impossible. Cystic spaces within the lesion are as well detected as by CT or MRI. New B-mode equipment with high energetic, high resolution good gray scale probes proved to be very helpful, giving as much information as Standardised A-mode.

Electronic dynamometry measurements, performed upon intraocular lens (IOL) haptics of prototype one-piece three-loop silicone lenses, accurately defined the relationships between elastic force and haptic displacement. Lens implantations in the capsular bag of dogs (loop span equal to capsular bag diameter, loops underformed immediately after the operation) were evaluated macrophotographically 5-8 months postoperatively. The highly constant elastic property of silicon rubber permitted quantitative correlation of subsequent in vivo haptic displacement with the resultant force vectors responsible for tissue contraction. The lens optics were well centered in 17 (85%) and slightly offcenter in 3 (15%) of 20 implanted eyes. Of the 60 supporting loops, 28 could be visualized sufficiently well to permit reliable haptic measurement. Of these 28, 20 (71%) were clearly displaced, ranging from 0.45 mm away from to 1.4 mm towards the lens' optic center. These extremes represented resultant vector forces of 0.20 and 1.23 mN respectively. Quantitative vector analysis permits better understanding of IOL-capsular interactions.

Fibrous histiocytomas are not rare. The diagnosis of fibrous histiocytoma might be evoked in case of a well circumscribed, heterogenous tumor, with bony deformation and no bony erosion. New B-mode equipment with high energetic, high resolution good gray scale probes proved to be very helpful, giving as much information as Standardised A-mode. It is always possible to differentiate such a tumor from cavernous hemangioma. Unfortunately, differential diagnosis with hemangiopericytoma and peripheral nerve sheath tumors is not always possible.

Mit Hilfe eines elektronischen Dynamometers werden die zur Verformung von Linsenhaptiken erforderlichen Krafte mit hoher Prazision bestimmt.

In patients with enlargement of the dural diameter of the optic nerve A- and B-scan ultrasonograms compared with coronal sections of high resolution NMR-images using a specially designed surface coils. According to preliminary results subarachnoidal space widening can be differentiated with both techniques, but the true nature and its chemical and physical properties still remain uncertain preoperatively. Tumors such as meningeomas, gliomas as well as various reasons of disc edema are analyzed.

Treatment with Ruthenium-106-radioactive plaques has proven to be an effective method achieving local tumor control of choroidal melanomas. (Lommatzsch and Vollmar, 1966; Lommatzschn, 1983; Forster et al., 1983; Forster et al., 1984) Success rates are dependent on a proper localization of the plaque as well as the exact measurements of tumor dimensions to calculate the irradiation dose required. Both parameters are highly dependent on ultrasonographical examinations. (Guthoff et al, 1983).

The sensitivity of modern pulsed duplex-scanners has been experimentally proven to be sufficient for measurements of flow velocity in the central retinal vessels. Clinical examinations were performed in 158 eyes with various diseases, including 27 malignant melanomas of the choroid. In vascular disturbancies the findings did not show significant deviations from the normal values.

Bei 27 Intraokularlinsentypen wurde die mechanische Stabilitat in der Sagittalachse vermessen. Die Fixierung der Linsen erfolgte in einer zylindrischen Plexiglashalterung mit einem Innendurchmesser von 10,5 mm. Eine Kraft von 0,005 N war in der Lage, das optische Zentrum der Linse um 0,05–0,5 mm auszulenken. Bei Anlenkung des Linsenaquators verlagerte sich der Mespunkt um 0,05–2 mm. Der Einflus der Haptikgeometrie auf die axiale Stabilitat der unterschiedlichen Linsenmodelle wird diskutiert.

The present paper reports on follow-up examinations of 246 patients after Ruthenium106 treatment of choroidal melanomas (follow-up time 1.8 to 13 years). In January 1988, 212 patients were alive and free of metastases; 15 had died, 12 of them of melanoma metastases, and 17 could not be followed up. In a retrospective analysis of factors influencing tumor-related mortality, the rate of regression of irradiated tumors was found to be particularly significant. The mean time taken to reduce tumor volume by half was 4.4 months in patients who died of metastases, as against 6.6 months in a matched group of survivors. Using discriminance analysis, the difference was found to be highly significant (P = 0.0058). In the total patient population, a significant correlation was found between pretreatment tumor volume and the probability of metastases (P = 0.058). It may be concluded, though with the qualification that the number of tumor-related deaths was small, that the tumor regression rate is an important factor in the prognosis for patients with Ruthenium-treated malignant choroidal melanomas.