Jörn Kuchenbecker

Ophthalmodynamometry: a reliable method for measuring intracranial pressure.

Under physiological conditions, the pressure in the central retinal vein is equal to or higher than the intracranial pressure (ICP) because the cerebrospinal fluid (CSF) passes the sheath of the optic nerve before draining into the cavernous sinus. The optic nerve sheath is where the ICP affects the retinal venous pressure. Ophthalmodynamometry (ODM) is a useful method for determining the central retinal artery pressure. While papilledema and a lack of venous pulsations are commonly used as a vague indication of the ICP, ODM may be advantageous for determining the pressure in the central retinal vein. Until now, however, the venous pressure has never been compared with the intracranial pressure. In the present study, the pressure in the central retinal vein was recorded in 31 patients while the ICP was simultaneously being recorded for various reasons. The results demonstrate a linear correlation (r = 0.968) between the pressure in the central retinal vein and the ICP. This correlation is of great practical value since until now, reliable intracranial pressure monitoring has only been possible by invasive means, by placing a probe either in the brain parenchyma or the ventricle. Ophthalmodynamometry is useful for momentary assessment of the ICP, can easily be repeated, and may be used whenever an elevated ICP is suspected in hydrocephalus, brain tumors and after head injury. However, it is not suitable for continuous ICP monitoring.

Laser iridocystotomy for bilateral acute angle-closure glaucoma secondary to iris cysts

PURPOSE To report laser iridocystotomy for bilateral acute angle-closure glaucoma secondary to peripheral iris cysts. METHOD Case report. RESULTS In a 55-year-old man with increased bilateral intraocular pressure, gonioscopy revealed varied angle narrowing. Bilateral angle-closure glaucoma secondary to peripheral iris cysts was diagnosed by ultrasound biomicroscopy. The peripheral iris cysts could not be seen in mydriasis by gonioscopy. Therefore, we decided to perform laser iridocystotomy with argon and Nd:YAG laser. Collapse of the cysts after laser treatment was demonstrated by ultrasound biomicroscopy. At follow-up, 9 months after laser treatment, intraocular pressure had dropped below 20 mm Hg in both eyes without further therapy. The iris cysts did not recur, which was demonstrated by ultrasound biomicroscopy. CONCLUSIONS Peripheral iris cysts may produce angle closure and may cause secondary angle-closure glaucoma. If transpupillary laser cystotomy is not possible, laser iridocystotomy may produce collapse of the iris cysts and correction of secondary angle closure.

Use of internet technologies for data acquisition in large clinical trials.

Data acquisition for automated processing is a central aspect of clinical trials with large numbers of cases because of their extensive demand for manpower. Scientific data can be collected using data forms, which are created in Hypertext Markup Language and published on the Internet. The completed data form can be returned via E-mail or Common Gateway Interface-Script and forwarded into a study database. For the Internet-based data acquisition of a prospective multicenter trial (e.g., on endophthalmitis incidence after cataract extraction), we developed two special HTML forms that can be opened in the ophthalmology departments homepage. A large number of acquired anonymous data has been collected via Internet and automatically transferred into the trial database. The Internet provides a fast and easy avenue for the acquisition of scientific data. This method of data acquisition and data processing will become more common place in multicenter clinical trials.

Inadvertent Scleral Perforation in Eye Muscle versus Retinal Detachment Buckle Surgery

Purpose. Inadvertent scleral perforation is a recognized complication of eye muscle and retinal detachment buckle surgery. If these operations are performed by the same surgeon, it is unknown which of these procedures has a higher risk of scleral perforation. Methods. In the period from 1999 until 2004, 427 eyes of 317 patients were operated using eye muscle surgery and 81 eyes of 80 patients with retinal detachment buckle surgery. All operations were performed by the same surgeon (JK). In a retrospective, single-center, comparative, observational study, the records of these patients were assessed to determine the number of scleral perforations with retinal damage or drainage of subretinal fluid. Results. In the group receiving retinal detachment buckle surgery there were two cases of scleral perforation. In one case, scleral perforation occurred during buckle installation and in the other case during placement of a cerclage. The rate of scleral perforation was 2.5 % per patient and per eye in this group. In the group receiving eye muscle surgery no scleral perforations occurred. Conclusion. The number of scleral perforations was higher in retinal detachment buckle surgery than in eye muscle surgery, with all procedures haveing been performed by the same surgeon.

Concentration of moxifloxacin in serum and human aqueous humor following a single 400 mg oral dose

Viscodissection (injection of an ophthalmic viscosurgical device [OVD] between the capsule and cortex) is recommended during phacoemulsification in eyes with congenital posterior polar cataracts to prevent posterior dislocation of lens material and/or anterior prolapse of vitreous because of a possible posterior capsule defect. One of us (R.M. Jr) theorized that routine viscodissection in eyes without congenital cataracts might reduce the incidence of posterior capsule rupture during phacoemulsification by creating a barrier that would prevent inadvertent contact between the posterior capsule and the phaco tip or other instruments. Because to our knowledge no study has been reported, we performed a prospective study using viscodissection during phacoemulsification. In the patients having viscodissection, approximately 0.15 cc of sodium hyaluronate 3.0%–chondroitin sulfate 4.0% (Viscoat) was injected in a side-to-side sweeping motion for 180 degrees opposite the primary phaco incision immediately after hydrodissection. All procedures were performed by the same surgeon (R.J.M.), who had extensive experience with phacoemulsification. The technique previously reported was used in all procedures. Briefly, the Alcon Infiniti system was used to sculpt a central nuclear bowl, followed by horizontal chopping of the nucleus into multiple segments. Chopping was accomplished by impaling the nucleus when it was of sufficient density. In eyes with a softer lens, manual chopping (no impaling) with the chopper and phaco tip was performed. Nuclear segments were then removed in the standard fashion. A retrospective analysis was performed by chart review. The number of eyes that experienced posterior capsule rupture during phacoemulsification using hydrodissection only between September 1, 2004, and January 31, 2005 (control group), was compared with the number of eyes that experienced posterior capsule rupture during phacoemulsification using hydrodissection and viscodissection (treatment group) between September 1, 2005, and January 31, 2006.

Colorimetric Analysis of Three Editions of the Velhagen-Broschmann Pseudoisochromatic Colour Plates

Purpose: Chromatic variations across different copies and different editions of pseudoisochromatic tests and violation of underlying principles of construction for individual plates can influence test results. Methods: We analysed the colorimetric characteristics of three different editions of Velhagen-Broschmann pseudoisochromatic plates (30th edition printed in 1995, 31st edition printed in 1997, 32nd edition printed in 2000). One hundred and twelve coloured dots of 18 plates were chosen from each edition. We measured RGB and CIE XYZ values using a spectrophotometer. Differences in lightness and chromaticity between corresponding dots of different editions were analysed in terms of ΔL* and Δu’v’, respectively. For each plate deviations from dichromatic confusion lines were analysed. Furthermore, we determined the relative luminance of a target compared to its background in terms of the Weber contrast. Results: The mean ΔL* across editions was 2.05 (±1.4) and the mean Δu’v’ was 0.0078 (±0.0029). For two plates the deviations of targets from dichromatic confusion lines exceeded suggested values. For a number of plates, the lightness contrast between the symbol and its background was high. Comparison with psychophysical data showed that these colour plates are easily detectable by colour-deficient observers. Conclusions: Lightness and chromatic variation across the three editions was moderate except for a small number of plates perhaps due to inaccuracies in the printing process. The design of several plates should be revised according to standard principles of construction of colour deficiency tests.

Einseitiger, pulsierender Exophthalmus

Die korrigierte Sehschärfe betrug beidseits 1,0. Das Goldmann-Gesichtsfeld zeigte regelrechte Außengrenzen. Die Patientin gab keine Doppelbilder an,und die Beweglichkeit der Augen war nicht eingeschränkt. Es bestand keine relative afferente Pupillenstörung. Hertel-Exophthalmometer: 15,0–16,5 mm (pulssynchron) – 103 mm – 15 mm. Die Lidspaltenweite betrug rechts 11 mm und links 9 mm (⊡ Abb. 1). Der Vorderabschnitt zeigte rechts keine Lidverdickung, keine Chemosis, keine gestauten episkleralen Gefäße, keine Lisch-Knötchen und war beidseits altersentsprechend. Der Augendruck (Applanationstonometrie) lag beidseits bei 15 mmHg. Der Augenhintergrund war beidseits altersentsprechend. Auskultation der Orbitae: kein pulssynchrones Strömungsgeräusch. Manuelle Kompression der rechten V. jugularis: keine Änderung des Zustandes. MRT-Orbita: knöcherner Defekt des Orbitadaches rechts mit Duravorwölbung im Sinne einer Meningoenzephalozele (⊡ Abb. 2). MR-Angiographie: Nachweis einzelner geschlängelt verlaufender Gefäße in der Orbita ohne Kontakt zu größeren Arterien sowie ohne Nachweis eines erhöhten Flusses, Digitale Subtraktionsangiographie (DSA) der rechten Karotis: keine pathologischen Gefäße im Bereich der Orbita (⊡ Abb. 3).

Quantitative und objektive topo-metrische Analyse von Drusenpapillen mit dem Heidelberg-Retina-Tomographen (HRT)

ZusammenfassungHintergrund und Ziele. Drusen des Sehnervenkopfes stellen eine der häufigsten Ursachen für kongenitale Papillenschwellungen dar. Sie führen zu Defekten der Nervenfaserschicht und zu Gesichtsfeldausfällen. Mittels Heidelberg-Retina-Tomographen (HRT) ist eine dreidimensionale topometrische Analyse von Papillenprominenzen und Messung der peripapillären retinalen Nervenfaserschicht (RNFL) möglich. Patienten und Methoden. Mittels HRT wurde bei 18 Augen von 9 Patienten mit sonographisch nachgewiesenen Drusen eine Topometrie der Papille durchgeführt. Als Vergleich diente eine Gruppe von 18 Augen von 9 altersentsprechenden augengesunden Patienten. Die statistische Auswertung der Daten erfolgte mittels univariater Varianzanalyse. Bei den Patienten mit Drusenpapillen wurde außerdem das Gesichtsfeld mittels 30° Computerperimetrie (Octopus 101), mit Bestimmung der mittleren Empfindlichkeit, des mittleren Defektes und der Verlustvarianz durchgeführt. Aufgrund unzuverlässiger Angaben (Zuverlässigkeitsfaktors >10) in der Computerperimetrie bei 4 von 18 Augen wurden nur die Daten von 14 Augen berücksichtigt. Es wurde die Korrelation von Gesichtsfeldbefunden mit HRT-Parametern durch Bestimmung des Pearson-Korrelationskoeffizienten ermittelt. Ergebnisse. Die peripapilläre “mean retinal nerve fiber layer (RNFL) thickness” der Patienten mit Drusenpapillen unterschied sich signifikant (p<,05) von den Werten der Augengesunden. In der Gruppe der Patienten mit Drusenpapille wurde ein negativer Korrelationskoeffizient (r) zwischen der “mean RNFL thickness” und der Verlustvarianz (r=−0,50; p=0,03) sowie zwischen der “RNFL cross section area” und der Verlustvarianz (r=−0,47; p=0,04) festgestellt. Schlussfolgerung. Mittels HRT konnte eine verminderte peripapilläre “mean retinal nerve fiber layer (RNFL) thickness” bei Drusenpapillen nachgewiesen werden. Diese korrelierte mit der Verlustvarianz des Gesichtsfeldes. Um eine quantitative und objektive topometrische Analyse bei Drusenpapillen durchzuführen, sollte der HRT verwendet werden.AbstractBackground and purpose. Optic nerve head drusen (ONHD) are one of the most frequent causes for congenital swelling of the optic nerve head. Visual field and retinal nerve fiber layer defects are reported in cases of ONHD. The Heidelberg Retina Tomograph (HRT) allows a 3-dimensional topometric analysis of the optic nerve disc and measurement of the peripapillary mean retinal nerve fiber layer. Patients and methods. A total of 18 eyes from 9 patients with sonographically confirmed drusen were analyzed with the HRT. Data were compared to a control group of 18 eyes from 9 matched healthy individuals. Statistical analyses were performed by using ANOVA (univariate). All patients with ONHD underwent a computerised visual field test (30°, Octopus 101). Due to a bad reliability factor of over 10 in the visual fields by 4 out of 18 eyes, only measurements from 14 eyes were included in the study. We correlated visual field and HRT parameters and calculated the Pearsons correlation coefficient (r). Results. We found a significant difference in the measured parameter mean retinal nerve fiber layer (RNFL) thickness (p<0.05) between the two groups. In the ONHD group a negative correlation coefficient was found between the peripapillary mean RNFL thickness and the loss variance (r=−0.50, p=0.03) as well as between the peripapillary RNFL cross-sectional area and the loss variance (r=−0.47, p=0.04). Conclusions. The HRT is able to detect a peripapillary RNFL thinning in cases with ONHD. The mean RNFL thickness correlated with the loss variance. The HRT should be used to perform a quantitative and objective topometric analysis in cases with ONHD.

Quantitative and objective topometrical analysis of drusen of the optic nerve head with the Heidelberg retina tomograph (HRT)

ZusammenfassungHintergrund und Ziele. Drusen des Sehnervenkopfes stellen eine der häufigsten Ursachen für kongenitale Papillenschwellungen dar. Sie führen zu Defekten der Nervenfaserschicht und zu Gesichtsfeldausfällen. Mittels Heidelberg-Retina-Tomographen (HRT) ist eine dreidimensionale topometrische Analyse von Papillenprominenzen und Messung der peripapillären retinalen Nervenfaserschicht (RNFL) möglich. Patienten und Methoden. Mittels HRT wurde bei 18 Augen von 9 Patienten mit sonographisch nachgewiesenen Drusen eine Topometrie der Papille durchgeführt. Als Vergleich diente eine Gruppe von 18 Augen von 9 altersentsprechenden augengesunden Patienten. Die statistische Auswertung der Daten erfolgte mittels univariater Varianzanalyse. Bei den Patienten mit Drusenpapillen wurde außerdem das Gesichtsfeld mittels 30° Computerperimetrie (Octopus 101), mit Bestimmung der mittleren Empfindlichkeit, des mittleren Defektes und der Verlustvarianz durchgeführt. Aufgrund unzuverlässiger Angaben (Zuverlässigkeitsfaktors >10) in der Computerperimetrie bei 4 von 18 Augen wurden nur die Daten von 14 Augen berücksichtigt. Es wurde die Korrelation von Gesichtsfeldbefunden mit HRT-Parametern durch Bestimmung des Pearson-Korrelationskoeffizienten ermittelt. Ergebnisse. Die peripapilläre “mean retinal nerve fiber layer (RNFL) thickness” der Patienten mit Drusenpapillen unterschied sich signifikant (p<,05) von den Werten der Augengesunden. In der Gruppe der Patienten mit Drusenpapille wurde ein negativer Korrelationskoeffizient (r) zwischen der “mean RNFL thickness” und der Verlustvarianz (r=−0,50; p=0,03) sowie zwischen der “RNFL cross section area” und der Verlustvarianz (r=−0,47; p=0,04) festgestellt. Schlussfolgerung. Mittels HRT konnte eine verminderte peripapilläre “mean retinal nerve fiber layer (RNFL) thickness” bei Drusenpapillen nachgewiesen werden. Diese korrelierte mit der Verlustvarianz des Gesichtsfeldes. Um eine quantitative und objektive topometrische Analyse bei Drusenpapillen durchzuführen, sollte der HRT verwendet werden.AbstractBackground and purpose. Optic nerve head drusen (ONHD) are one of the most frequent causes for congenital swelling of the optic nerve head. Visual field and retinal nerve fiber layer defects are reported in cases of ONHD. The Heidelberg Retina Tomograph (HRT) allows a 3-dimensional topometric analysis of the optic nerve disc and measurement of the peripapillary mean retinal nerve fiber layer. Patients and methods. A total of 18 eyes from 9 patients with sonographically confirmed drusen were analyzed with the HRT. Data were compared to a control group of 18 eyes from 9 matched healthy individuals. Statistical analyses were performed by using ANOVA (univariate). All patients with ONHD underwent a computerised visual field test (30°, Octopus 101). Due to a bad reliability factor of over 10 in the visual fields by 4 out of 18 eyes, only measurements from 14 eyes were included in the study. We correlated visual field and HRT parameters and calculated the Pearsons correlation coefficient (r). Results. We found a significant difference in the measured parameter mean retinal nerve fiber layer (RNFL) thickness (p<0.05) between the two groups. In the ONHD group a negative correlation coefficient was found between the peripapillary mean RNFL thickness and the loss variance (r=−0.50, p=0.03) as well as between the peripapillary RNFL cross-sectional area and the loss variance (r=−0.47, p=0.04). Conclusions. The HRT is able to detect a peripapillary RNFL thinning in cases with ONHD. The mean RNFL thickness correlated with the loss variance. The HRT should be used to perform a quantitative and objective topometric analysis in cases with ONHD.

Trypan-Blue-Assisted Anterior Continuous Curvilinear Capsulorhexis in a Case of Ocular Pemphigoid

Purpose: To report on trypan-blue-assisted anterior continuous curvilinear capsulorhexis (ACCC) in a case of ocular pemphigoid. Methods: Interventional case report. Results: Due to the reduced visibility especially in the corneal periphery caused by the ocular pemphigoid, trypan blue 0,06% (Acri.Blue®) was used to stain the anterior capsule of the lens. Then anterior continuous curvilinear capsulorhexis was performed. Due to the blue staining, the visualization of the margin of the rhexis was always good and phacoemulsification procedure was successfully performed afterwards. During the follow-up period of 12-months-postsurgically, no exacerbation of the ocular pemphigoid occurred. Conclusions: The use of trypan blue staining of the anterior capsule enabled the surgeon to perform a safe anterior continuous curvilinear capsulorhexis and a subsequent phacoemulsification in ocular pemphigoid. No progression of the ocular pemphigoid was seen within the 12-months-post-surgery period.