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Ophthalmologe | 2007

A comparison of rebound tonometry (ICare) with TonoPenXL and Goldmann applanation tonometry

W. Schreiber; Christian K. Vorwerk; Achim Langenbucher; W. Behrens-Baumann; A. Viestenz

ZusammenfassungHintergrundMit dem Applanationstonometer nach Goldmann und dem Dynamischen Contour-Tonometer (PASCAL) stehen spaltlampenadaptierte Tonometer zur Verfügung. Bettlägerige Patienten oder Kinder können mitunter nur mit kleineren, handgehaltenen Tonometern untersucht werden (z.xa0B. TonopenXL, Perkins-Tonometer, Draeger-Tonometer). Ziel war es, das auf der Rebound-Methode basierende handgehaltene ICare-Tonometer zu evaluieren.Patienten und MethodeUntersucht wurden 102 Augen durch 2 erfahrene Augenärzte: 1. ophthalmologischer Status, 2. zentrale Hornhautbrechkraft (Zeiss IOL-Master), 3. zentrale Hornhautdicke (Tomey-Ultraschall-Pachymeter, 5 aufeinander folgende Messungen), 4. Intraokulardruck (IOD)-Messung mit dem Goldmann-Applanationstonometer (GAT) 1×, 5. TonopenXL (1×), 6. ICare jeweils 3 aufeinander folgende Messzyklen zu je 6 Messungen.ErgebnisseDer IODGAT betrug im Mittel 13,2±3,0xa0mmHg im Vergleich zum IODTonopenXL mit 13,4±3,1xa0mmHg und zum IODICare (1. Messzyklus: 14,6±3,9xa0mmHg). Die einzelnen IOD-Werte korrelierten miteinander (r=0,592–0,642; p<0,001). Zwischen den einzelnen Messmethoden gab es große intraindividuelle Unterschieden mit einer Spanne bis zu 17xa0mmHg. Während der 3 ICare-Messzyklen zeigte sich ein Tonographieeffekt (Abnahme des IOD von 14,6xa0mmHg bei der ersten ICare-Messung, über 14,2xa0mmHg bei der zweiten, auf 14,0xa0mmHg bei der dritten ICare-Messung). Die Reliabilität der ICare-Messungen war sehr hoch (Cronbachs α=0,974).SchlussfolgerungenMit dem ICare steht dem Augenarzt ein leicht zu bedienendes handgehaltenes Tonometer mit hoher Reliabilität zur Verfügung, dessen Messwerte mit denen des Goldmann-Tonometers vergleichbar erscheinen. Bei unmittelbar aufeinander folgenden Kontrollmessungen sollte ein Tonographieeffekt von 0,6xa0mmHg beachtet werden.AbstractBackgroundGoldmann applanation tonometry and dynamic contour tonometry (PASCAL) are two well established slit lamp mounted tonometric methods. Intraocular pressure measurement in bedridden patients and children is often only possible using hand held tonometers (TonoPenXL, Perkins tonometer, Draeger tonometer). This study was performed to evaluate the hand held ICare tonometer, which is based on the rebound method.MethodsA total of 102 eyes were examined by two highly experienced ophthalmologists for: 1) ophthalmological status, 2) central corneal power (Zeiss IOL-Master), 3) central corneal thickness (Tomey ultrasound pachymetry, five successive measurements, SD<5%), 4) intraocular pressure (IOP) measurement with the Goldmann applantation tonometer (GAT) 1×, 5) TonoPenXL (1×), 6) ICare with three successive measurement series of 6 single measurements.ResultsThe mean IOPGAT was 13.2±3.0xa0mmHg compared with the mean IOPTonoPenXL (13.4±3.1xa0mmHg) and with the IOPICare (mean value of first measurement series: 13.4±3.1xa0mmHg). The series of measurements with the ICare showed a tonography effect (decrease of IOP from 14.6xa0mmHg at the first measurement and 14.2xa0mmHg at the second to 14.0xa0at the third measurement). The ICare-measurements were highly reliable (Cronbach’s alpha=0.974) and showed a good correlation between the measurement series (r=0.592–0.642; p<0.001). There was a great intra-individual variability of up to 17xa0mmHg between the GAT, TonoPenXL and ICare methods.ConclusionsThe ICare tonometer is easy to handle and high reliability. The data are comparable with those from the Goldmann tonometer. A tonography effect of 0.6xa0mmHg in the successive measurement series was found.


Ophthalmologe | 2007

Evaluierung der Reboundtonometrie (ICare) im Vergleich zum TonopenXL und dem Goldmann- Applanationstonometer

W. Schreiber; Christian K. Vorwerk; Achim Langenbucher; W. Behrens-Baumann; A. Viestenz

ZusammenfassungHintergrundMit dem Applanationstonometer nach Goldmann und dem Dynamischen Contour-Tonometer (PASCAL) stehen spaltlampenadaptierte Tonometer zur Verfügung. Bettlägerige Patienten oder Kinder können mitunter nur mit kleineren, handgehaltenen Tonometern untersucht werden (z.xa0B. TonopenXL, Perkins-Tonometer, Draeger-Tonometer). Ziel war es, das auf der Rebound-Methode basierende handgehaltene ICare-Tonometer zu evaluieren.Patienten und MethodeUntersucht wurden 102 Augen durch 2 erfahrene Augenärzte: 1. ophthalmologischer Status, 2. zentrale Hornhautbrechkraft (Zeiss IOL-Master), 3. zentrale Hornhautdicke (Tomey-Ultraschall-Pachymeter, 5 aufeinander folgende Messungen), 4. Intraokulardruck (IOD)-Messung mit dem Goldmann-Applanationstonometer (GAT) 1×, 5. TonopenXL (1×), 6. ICare jeweils 3 aufeinander folgende Messzyklen zu je 6 Messungen.ErgebnisseDer IODGAT betrug im Mittel 13,2±3,0xa0mmHg im Vergleich zum IODTonopenXL mit 13,4±3,1xa0mmHg und zum IODICare (1. Messzyklus: 14,6±3,9xa0mmHg). Die einzelnen IOD-Werte korrelierten miteinander (r=0,592–0,642; p<0,001). Zwischen den einzelnen Messmethoden gab es große intraindividuelle Unterschieden mit einer Spanne bis zu 17xa0mmHg. Während der 3 ICare-Messzyklen zeigte sich ein Tonographieeffekt (Abnahme des IOD von 14,6xa0mmHg bei der ersten ICare-Messung, über 14,2xa0mmHg bei der zweiten, auf 14,0xa0mmHg bei der dritten ICare-Messung). Die Reliabilität der ICare-Messungen war sehr hoch (Cronbachs α=0,974).SchlussfolgerungenMit dem ICare steht dem Augenarzt ein leicht zu bedienendes handgehaltenes Tonometer mit hoher Reliabilität zur Verfügung, dessen Messwerte mit denen des Goldmann-Tonometers vergleichbar erscheinen. Bei unmittelbar aufeinander folgenden Kontrollmessungen sollte ein Tonographieeffekt von 0,6xa0mmHg beachtet werden.AbstractBackgroundGoldmann applanation tonometry and dynamic contour tonometry (PASCAL) are two well established slit lamp mounted tonometric methods. Intraocular pressure measurement in bedridden patients and children is often only possible using hand held tonometers (TonoPenXL, Perkins tonometer, Draeger tonometer). This study was performed to evaluate the hand held ICare tonometer, which is based on the rebound method.MethodsA total of 102 eyes were examined by two highly experienced ophthalmologists for: 1) ophthalmological status, 2) central corneal power (Zeiss IOL-Master), 3) central corneal thickness (Tomey ultrasound pachymetry, five successive measurements, SD<5%), 4) intraocular pressure (IOP) measurement with the Goldmann applantation tonometer (GAT) 1×, 5) TonoPenXL (1×), 6) ICare with three successive measurement series of 6 single measurements.ResultsThe mean IOPGAT was 13.2±3.0xa0mmHg compared with the mean IOPTonoPenXL (13.4±3.1xa0mmHg) and with the IOPICare (mean value of first measurement series: 13.4±3.1xa0mmHg). The series of measurements with the ICare showed a tonography effect (decrease of IOP from 14.6xa0mmHg at the first measurement and 14.2xa0mmHg at the second to 14.0xa0at the third measurement). The ICare-measurements were highly reliable (Cronbach’s alpha=0.974) and showed a good correlation between the measurement series (r=0.592–0.642; p<0.001). There was a great intra-individual variability of up to 17xa0mmHg between the GAT, TonoPenXL and ICare methods.ConclusionsThe ICare tonometer is easy to handle and high reliability. The data are comparable with those from the Goldmann tonometer. A tonography effect of 0.6xa0mmHg in the successive measurement series was found.


Ophthalmologe | 2006

Evaluation of dynamic contour tonometry in penetrating keratoplasties

A. Viestenz; Achim Langenbucher; B. Seitz

PURPOSEnThe PASCAL dynamic contour tonometer (DCT) adapted to the corneal geometry is a new approach for digital measurement of intraocular pressure (IOP). The purpose of this study was to evaluate the DCT vs Goldmann applanation tonometry (GAT) in penetrating keratoplasties.nnnMETHODnWe included 92 consecutive eyes after penetrating keratoplasty (57 without sutures, 32 with 2 running sutures, 3 with 1 running suture) in this prospective cross-sectional study. The mean outcome measurements were central corneal power (Zeiss ophthalmometer) and central corneal thickness (ultrasound pachymetry Tomey AL-1000). IOP was evaluated in consecutive measurements including 3x DCT and 1x GAT.nnnRESULTSnThe mean IOP measured with DCT was 18.3+/-4.0 mmHg in contrast to GAT with 14.3+/-4.1 mmHg (p<0.001). Both methods showed a strong correlation of IOP values (r=0.74, p<0.001). The quality of measurement in keratoplasties after complete suture removal was between Q1 and Q3 in 88% with DCT in contrast to 59% with two running sutures. Three values with a reproducibility of 0.97 (Cronbachs alpha) could be obtained in 53 eyes without sutures and with a reproducibility of 0.94 (Cronbachs alpha) in 20 eyes (62.5%) with 2 running sutures. DCT or GAT did not correlate with central corneal thickness. The mean astigmatism did not differ between keratoplasties without sutures (4.86+/-3.35 D) or with two running sutures (4.2+/-2.8 D, p=0.38).nnnCONCLUSIONSnThe DCT provides reproducible IOP measurements in penetrating keratoplasties with significantly higher values in comparison to GAT. Nevertheless, as known for GAT, postoperative intrastromal corneal sutures after penetrating keratoplasty disturb the exact DCT measurement as well.ZusammenfassungHintergrundMit dem dynamischen Konturtonometer PASCAL® („Dynamic Contour Tonometer“; DCT) steht ein digitales Messgerät zur Bestimmung des Intraokulardrucks (IOD) zur Verfügung, welches der natürlichen Geometrie der Hornhaut angenähert wurde. Ziel war die Evaluierung des DCT im Vergleich zum Goldmann-Applanationstonometer (GAT) bei Hornhäuten nach penetrierender Keratoplastik.MethodenDie prospektive Querschnittstudie umfasste 92 konsekutive Augen von Patienten mit penetrierender Keratoplastik (57 ohne Fäden, 32 mit zwei fortlaufenden Fäden, 3 mit einem fortlaufenden Faden). Erfasst wurden die zentrale Hornhautbrechkraft (Zeiss-Ophthalmometer) und die zentrale Hornhautdicke (Ultraschallpachymeter Tomey AL-1000). Der IOD wurde direkt aufeinander folgend 3-mal mit dem DCT und abschließend einmal mittels GAT gemessen.ErgebnisseDer mittlere IODDCT betrug 18,3±4,0xa0mmHg gegenüber dem IODGAT mit 14,3±4,1xa0mmHg (p<0,001). Die IOD-Werte beider Messmethoden korrelierten stark miteinander (r=0,74, p<0,001). Die Qualität der Messwerte bei Keratoplastiken nach kompletter Fadenentfernung lag mit dem DCT in 88% zwischen Q1–Q3 bei drei Messungen im Gegensatz zu 59% bei liegenden Hornhautfäden. Bei 53xa0Augen ohne Hornhautfäden konnten drei DCT-Messungen mit einer Reproduzierbarkeit von 0,97 (Cronbachs alpha) gegenüber 20xa0Augen bei zwei liegenden Hornhautfäden mit einer Reproduzierbarkeit der DCT von 0,94 (Cronbachs alpha) erhoben werden. Sowohl mit dem GAT als auch mit dem DCT gemessen zeigte sich keine Abhängigkeit von der Hornhautdicke. Die Höhe des mittleren Astigmatismus unterschied sich nicht zwischen Keratoplastiken ohne Fäden (4,86±3,35xa0dpt) und mit zwei fortlaufenden Fäden (4,2±2,8xa0dpt, p=0,38).SchlussfolgerungDas DCT (PASCAL®) liefert reproduzierbare IOD-Messwerte nach penetrierender Keratoplastik, misst jedoch signifikant höher als das GAT. Analog zum GAT stellen die noch liegenden Hornhautfäden einen nicht zu vernachlässigenden Störfaktor dar.AbstractPurposeThe PASCAL dynamic contour tonometer (DCT) adapted to the corneal geometry is a new approach for digital measurement of intraocular pressure (IOP). The purpose of this study was to evaluate the DCT vs Goldmann applanation tonometry (GAT) in penetrating keratoplasties.MethodWe included 92 consecutive eyes after penetrating keratoplasty (57 without sutures, 32 with 2 running sutures, 3 with 1 running suture) in this prospective cross-sectional study. The mean outcome measurements were central corneal power (Zeiss ophthalmometer) and central corneal thickness (ultrasound pachymetry Tomey AL-1000). IOP was evaluated in consecutive measurements including 3x DCT and 1x GAT.ResultsThe mean IOP measured with DCT was 18.3±4.0xa0mmHg in contrast to GAT with 14.3±4.1xa0mmHg (p<0.001). Both methods showed a strong correlation of IOP values (r=0.74, p<0.001). The quality of measurement in keratoplasties after complete suture removal was between Q1 and Q3 in 88% with DCT in contrast to 59% with two running sutures. Three values with a reproducibility of 0.97 (Cronbach’s alpha) could be obtained in 53 eyes without sutures and with a reproducibility of 0.94 (Cronbach’s alpha) in 20 eyes (62.5%) with 2 running sutures. DCT or GAT did not correlate with central corneal thickness. The mean astigmatism did not differ between keratoplasties without sutures (4.86±3.35xa0D) or with two running sutures (4.2±2.8xa0D, p=0.38).ConclusionsThe DCT provides reproducible IOP measurements in penetrating keratoplasties with significantly higher values in comparison to GAT. Nevertheless, as known for GAT, postoperative intrastromal corneal sutures after penetrating keratoplasty disturb the exact DCT measurement as well.


Ophthalmologe | 2008

Aniridie-Intraokularlinsen bei Augen mit traumatischen Irisdefekten

K. Schmitz; A. Viestenz; Daniel Meller; W. Behrens-Baumann; K.-P. Steuhl

BACKGROUNDnGlobe injuries frequently are the cause of permanent loss of visual function. Especially ruptures of the globe have a 50 times lower chance of achieving a final visual acuity better than 20/200 as compared to contusions of the globe. Besides injury to the retina and choroids, injury of the iris-lens diaphragm plays an important role for visual rehabilitation (10% iris defects and 1% aniridia after blunt trauma). Against this background the surgical results after implantation of aniridia intraocular lenses were investigated.nnnPATIENTS AND METHODSnEleven patients (41.9+/-19.6 years of age) after globe injury (three ruptures of the globe, eight penetrating injuries with trauma of the iris) were implanted with an aniridia IOL.nnnRESULTSnThe implantation of an aniridia IOL was performed on average 1.0+/-0.6 years (range: 0.4-2.3 years) after the primary injury. In ten eyes an aniridia IOL model HMK ANI 2 (Ophtec/Polytech) was implanted and in one eye an aniridia IOL model 67 (Morcher). Most patients were very satisfied with the results achieved (average corrected visual acuity 0.48; 0.05-1.0). Of the operated eyes, 63% reached a visual acuity > or = 0.4. All patients noticed a significant reduction in glare disability as compared to the preoperative condition. The incidence of secondary glaucoma remained unchanged after the secondary implantation. One patient demonstrated retinal detachment 3 months after receiving the secondary implant, which was successfully treated with vitrectomy and gas tamponade.nnnCONCLUSIONSnThe implantation of aniridia IOLs seems to be a beneficial therapeutic option in post-traumatic eyes with partial or complete aniridia and aphakia with good visual recovery. During the postoperative follow-up special attention must be paid to sufficient regulation of intraocular pressure and to the retinal situation.ZusammenfassungHintergrundBulbusverletzungen führen häufig zu einer dauerhaften Beeinträchtigung des Sehvermögens. Insbesondere bei Bulbusrupturen ist die Chance, einen Visus >0,1 zu erreichen 50-mal geringer als nach Bulbuskontusion. Neben Netzhaut- und Aderhauttrauma kommt dem Iris-Linsendiaphragma (ca. 10% Irisdefekte und 1% Aniridie nach stumpfer Verletzung) bei der visuellen Rehabilitation eine häufig unterschätzte Rolle zu. Vor diesem Hintergrund wurden die operativen Ergebnisse nach Implantation von Aniridie-Intraokularlinsen untersucht.Patienten und Methoden11xa0Patienten (41,9±19,6xa0Jahre) mit Z.xa0n. Bulbustrauma (3-mal Bulbusruptur, 8-mal penetrierende Bulbusverletzung mit Iris-Linsenbeteiligung) wurden mit einem Aniridie-Implantat versorgt.ErgebnisseDie Implantation der Aniridie-IOL erfolgte im Mittel 1,0±0,6xa0Jahre (Spanne 0,4–2,3xa0Jahre) nach der primären Wundversorgung. Bei 10 Augen wurde eine Aniridie-IOL Modell HMK ANI 2 (Ophtec/Polytech), bei 1 Auge eine Aniridie-IOL Modell 67 (Morcher) implantiert. Die postoperative Patientenzufriedenheit war hoch (korrigierter Visus im Mittel 0,48; 0,05–1,0). 63% der operierten Augen erreichten einen Visus ≥0,4. Alle Patienten erfuhren eine Reduktion der präoperativ bestandenen Blendungsempfindlichkeit. Die Inzidenz von Sekundärglaukomen wurde durch die Sekundärimplantation nicht erhöht. Ein Patient erlitt 3xa0Monate nach Implantation eine Netzhautablösung, die durch ppV und Gastamponade behoben werden konnte.SchlussfolgerungBei Trauma-Augen mit partieller oder vollständiger Aniridie und gleichzeitig bestehender Aphakie erscheint die Implantation von Aniridie-IOLs als eine therapeutische Option mit z.xa0T. guter visueller Rehabilitation. Bei der postoperativen Verlaufskontrolle ist auf ausreichende Tensionseinstellung und Ablatioprodromi zu achten.AbstractBackgroundGlobe injuries frequently are the cause of permanent loss of visual function. Especially ruptures of the globe have a 50 times lower chance of achieving a final visual acuity better than 20/200 as compared to contusions of the globe. Besides injury to the retina and choroids, injury of the iris-lens diaphragm plays an important role for visual rehabilitation (10% iris defects and 1% aniridia after blunt trauma). Against this background the surgical results after implantation of aniridia intraocular lenses were investigated.Patients and methodsEleven patients (41.9±19.6xa0years of age) after globe injury (three ruptures of the globe, eight penetrating injuries with trauma of the iris) were implanted with an aniridia IOL. ResultsThe implantation of an aniridia IOL was performed on average 1.0±0.6xa0years (range: 0.4–2.3xa0years) after the primary injury. In ten eyes an aniridia IOL model HMK ANI 2 (Ophtec/Polytech) was implanted and in one eye an aniridia IOL model 67 (Morcher). Most patients were very satisfied with the results achieved (average corrected visual acuity 0.48; 0.05–1.0). Of the operated eyes, 63% reached a visual acuity ≥0.4. All patients noticed a significant reduction in glare disability as compared to the preoperative condition. The incidence of secondary glaucoma remained unchanged after the secondary implantation. One patient demonstrated retinal detachment 3xa0months after receiving the secondary implant, which was successfully treated with vitrectomy and gas tamponade.ConclusionsThe implantation of aniridia IOLs seems to be a beneficial therapeutic option in post-traumatic eyes with partial or complete aniridia and aphakia with good visual recovery. During the postoperative follow-up special attention must be paid to sufficient regulation of intraocular pressure and to the retinal situation.


Ophthalmologe | 2013

DALK and penetrating laser keratoplasty for advanced keratoconus

B. Seitz; Claus Cursiefen; M. El-Husseiny; A. Viestenz; Achim Langenbucher; N. Szentmáry

BACKGROUNDnIn cases of contact lens intolerance and/or central corneal scars, corneal transplantation is indicated for advanced keratoconus. This can be performed as deep anterior lamellar keratoplasty (DALK) or as penetrating keratoplasty (PKP). The German keratoplasty registry shows that the proportion of anterior lamellar grafts in Germany has remained stable at approximately 5u2009% in recent years.nnnMETHODSnUp to now DALK has not been technically standardized but can result in a good visual acuity using the big bubble technique if Descemets membrane is laid bare intraoperatively. In 10-20u2009% a conversion to PKP is required if perforation of Descemets membrane occurs. In cases of advanced keratoconus PKP is still the method of first choice especially after corneal hydrops due to rupture of Descemets membrane. Non-contact excimer laser trephination seems to be especially beneficial for eyes with iatrogenic keratectasia after LASIK and those with repeat grafts in cases of keratoconus recurrence due to the graft being too small. For donor trephination from the epithelial side, an artificial chamber is used. Wound closure is achieved by a double running cross-stitch suture according to Hoffmann. Graft size is adapted individually depending on corneal size (as large as possible and as small as necessary). Limbal centration is given priority intraoperatively due to optical displacement of the pupil.nnnRESULTSnProspective clinical studies have shown that the technique of non-contact excimer laser PKP improves donor and recipient centration, reduces vertical tilt and horizontal torsion of the graft in the recipient bed, thus resulting in significantly less all-sutures-out keratometric astigmatism (2.8xa0D versus 5.7xa0D), higher regularity of the topography (SRI 0.80 vs. 0.98) and better visual acuity (0.80 vs. 0.63) in contrast to the motor trephine. The stage of the disease does not influence functional outcome after excimer laser PKP.nnnCONCLUSIONSnIn cases with optimal course DALK achieves the same visual outcome as mechanical PKP but the healthy endothelium can be preserved and endothelial immune reactions are prevented in keratoconus. In contrast to the undisputed clinical advantages of excimer laser keratoplasty with orientation teeth/notches in keratoconus, the major disadvantage of femtosecond laser application is still the necessity of suction and applanation of the cone during trephination.ZusammenfassungHintergrundBei Kontaktlinsenintoleranz und/oder zentralen Hornhautnarben ist beim fortgeschrittenen Keratokonus die Korneatransplantation angezeigt. Diese kann prinzipiell als anteriore lamelläre Keratoplastik (bevorzugt als „deep anterior lamellar keratoplasty“, DALK) oder als perforierende Keratoplastik (PKP) durchgeführt werden. Das Deutsche Keratoplastikregister weist für die letzten Jahre stabil einen Anteil von etwa 5u2009% an anterioren lamellären Keratoplastiken aus.MethodenDie DALK ist bis heute technisch nicht standardisiert, kann aber mittels Big-Bubble-Technik zu guten Visusergebnissen führen, wenn intraoperativ die Descemet-Membran freigelegt wurde. In 10–20u2009% der Eingriffe ist bei Perforation der Descemet-Membran die Konversion zur PKP nötig. Bei fortgeschrittenem Keratokonus – besonders bei Zustand nach akutem Keratokonus mit Descemet-Ruptur – wird die PKP nach wie vor für die Methode der Wahl gehalten. Die kontaktfreie nichtmechanische Excimerlasertrepanation bietet sich in besonderem Maße auch für die iatrogene Keratektasie nach Laser-in-situ-Keratomileusis (LASIK) und die Rekeratoplastik bei sog. „Keratokonusrezidiv“ wegen zu kleinem Transplantat an. Für die Spendertrepanation von epithelial wird eine künstliche Vorderkammer eingesetzt, der wasserdichte Wundverschluss erfolgt mittels doppelt fortlaufender Naht nach Hoffmann. Die Transplantatgröße wird individuell an die Hornhautgröße angepasst („so groß wie möglich, so klein wie nötig“). Der Limbuszentrierung wird wegen der optischen Verlagerung der Pupille intraoperativ der Vorzug gegeben.ErgebnissePublizierte klinische Studien haben gezeigt, dass die Technik der Non-contact-Excimerlasertrepanation die Spender- und Empfängerzentrierung, die „vertikale Verkippung“ sowie die „horizontale Torsion“ des Transplantates im Empfängerbett verbessert. Daraus resultieren nach Fadenentfernung ein signifikant geringerer Astigmatismus (2,8 vs. 5,7xa0dpt), eine höhere Regularität der Topografie [Surface Regularity Index (SRI) 0,80 vs. 0,98] und vor allem ein besserer Visus (0,80 vs. 0,63) im Vergleich zum Motortrepan. Die funktionellen Ergebnisse nach Excimerlaser-PKP sind bei Operation im fortgeschrittenen Stadium nicht schlechter als bei Operation in früheren Stadien des Keratokonus.SchlussfolgerungenBei optimalem Verlauf kann die DALK bei Erhalt des eigenen gesunden Endothels zu Visusergebnissen analog denen der PKP führen und endotheliale Immunreaktionen komplett vermeiden. Den unbestrittenen klinischen Vorteilen der Excimerlasertrepanation für die PKP bei Keratokonus steht bei der Femtosekundenlasertrepanation die Notwendigkeit der Ansaugung und Applanation des Konus als gravierender Nachteil gegenüber.AbstractBackgroundIn cases of contact lens intolerance and/or central corneal scars, corneal transplantation is indicated for advanced keratoconus. This can be performed as deep anterior lamellar keratoplasty (DALK) or as penetrating keratoplasty (PKP). The German keratoplasty registry shows that the proportion of anterior lamellar grafts in Germany has remained stable at approximately 5u2009% in recent years.MethodsUp to now DALK has not been technically standardized but can result in a good visual acuity using the big bubble technique if Descemet’s membrane is laid bare intraoperatively. In 10–20u2009% a conversion to PKP is required if perforation of Descemet’s membrane occurs. In cases of advanced keratoconus PKP is still the method of first choice especially after corneal hydrops due to rupture of Descemet’s membrane. Non-contact excimer laser trephination seems to be especially beneficial for eyes with iatrogenic keratectasia after LASIK and those with repeat grafts in cases of keratoconus recurrence due to the graft being too small. For donor trephination from the epithelial side, an artificial chamber is used. Wound closure is achieved by a double running cross-stitch suture according to Hoffmann. Graft size is adapted individually depending on corneal size (as large as possible and as small as necessary). Limbal centration is given priority intraoperatively due to optical displacement of the pupil.ResultsProspective clinical studies have shown that the technique of non-contact excimer laser PKP improves donor and recipient centration, reduces vertical tilt and horizontal torsion of the graft in the recipient bed, thus resulting in significantly less all-sutures-out keratometric astigmatism (2.8xa0D versus 5.7xa0D), higher regularity of the topography (SRI 0.80 vs. 0.98) and better visual acuity (0.80 vs. 0.63) in contrast to the motor trephine. The stage of the disease does not influence functional outcome after excimer laser PKP.ConclusionsIn cases with optimal course DALK achieves the same visual outcome as mechanical PKP but the healthy endothelium can be preserved and endothelial immune reactions are prevented in keratoconus. In contrast to the undisputed clinical advantages of excimer laser keratoplasty with orientation teeth/notches in keratoconus, the major disadvantage of femtosecond laser application is still the necessity of suction and applanation of the cone during trephination.


Journal of Cataract and Refractive Surgery | 2012

Comparison of Goldmann applanation and dynamic contour tonometry before and after cataract surgery

Mitja A. Heinrich; Timo Eppig; Achim Langenbucher; S. Walter; W. Behrens-Baumann; A. Viestenz

PURPOSE: To validate changes in intraocular pressure (IOP) after phacoemulsification with intraocular lens (IOL) implantation without pressure‐lowering surgery in previously unoperated eyes of normal and glaucoma patients. SETTING: University Eye Clinic, Otto‐von‐Guericke‐University, Magdeburg, Germany. DESIGN: Cohort study. METHODS: The IOP in both eyes of patients was determined by Goldmann applanation tonometry (GAT) and dynamic contour tonometry (DCT) 1 to 2 days before and after uneventful unilateral surgery. Central corneal thickness was used to correct raw GAT readings. RESULTS: Of the 50 patients having unilateral phacoemulsification, 29 had had cataract extraction in the contralateral eye. The mean baseline IOP was 17.4 ± 4.4 mm Hg (GAT) and 16.6 ± 2.9 mm Hg (DCT). Postoperatively, the GAT IOP decreased to 16.4 ± 6.5 mm Hg and the DCT IOP increased slightly to 17.1 ± 4.1 mm Hg. The mean tonometer difference (ΔIOP = GAT − DCT) amounted to ΔIOPpre = +0.75 ± 2.69 mm Hg in phakic eyes and ΔIOPpost = −0.70 ± 3.76 mm Hg in pseudophakic eyes (P=.0011). Consistent results were found in pairs of phakic eyes and pseudophakic eyes (mean IOP 18.0 ± 4.8 mm Hg [GAT] and 17.0 ± 3.3 mm Hg [DCT]). In fellow eyes, the mean GAT reading was 13.4 ± 4.4 mm Hg and the mean DCT value, 14.8 ± 2.4 mm Hg. ΔIOPphakic was +1.04 ± 2.75 mm Hg and ΔIOPpseudophakic was −1.48 ± 2.78 mm Hg (P=.00000021). CONCLUSIONS: The GAT IOP readings in pseudophakic eyes seemed to be falsely low. Hence, special attention in the screening, diagnosis, and management of glaucoma is necessary. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned.


Ophthalmologe | 2007

Torische Intraokularlinsen und Astigmatismuskorrektur

A. Viestenz; S. Walter; Anja Viestenz; W. Behrens-Baumann; Achim Langenbucher

ZusammenfassungTorische Intraokularlinsen (tIOLs) können den kornealen Astigmatismus korrigieren. Der Hintergrund dieser Übersicht ist1.die biometrischen, keratometrischen und topographischen Konditionen für eine tIOL-Implantation zu beschreiben,2.Vor- und Nachteile von tIOLs aufzuzeigen,3.Indikationen und Kontraindikationen für tIOLs zu definieren,4.klinische Empfehlungen für die Implantation von tIOLs anzubieten und5.die Spezifikationen der derzeit kommerziell erhältlichen tIOLs aufzuzeigen.AbstractToric intraocular lenses (tIOLs) have the potential to correct corneal astigmatism. The purpose of this review paper is1.to describe the biometric, keratometric and topographic conditions for implantion of tIOLs,2.to highlight the advantages and disadvantages of tIOLs,3.to define indications for and contraindications to tIOL implantation,4.to provide clinical recommendations for the implantation of toric lenses, and5.to report the specifications of all tIOLs that are currently available commercially.Toric intraocular lenses (tIOLs) have the potential to correct corneal astigmatism. The purpose of this review paper is: 1. to describe the biometric, keratometric and topographic conditions for implantion of tIOLs, 2. to highlight the advantages and disadvantages of tIOLs, 3. to define indications for and contraindications to tIOL implantation, 4. to provide clinical recommendations for the implantation of toric lenses, and 5. to report the specifications of all tIOLs that are currently available commercially.


Ophthalmologe | 2008

Biometrie des vorderen Augensegmentes mittels optischer Kohärenztomographie

A. Viestenz; S. Vogt; Achim Langenbucher; S. Walter; W. Behrens-Baumann

ZusammenfassungHintergrundDie digitale Visualisierung des Augenvorderabschnittes zur Diagnostik und Biometrie gewinnt zunehmend an Bedeutung. Als kommerziell erhältliche optische Kohärenztomographen (OCT) wurden das Visante-OCT (Carl-Zeiss Meditec, Jena) und das Spaltlampen-OCT (SL-OCT; Heidelberg Engineering) evaluiert. AM SC-OCT wurden zusätzlich ein manueller und ein semiautomatischer Biometriealgorithmus miteinander verglichen.Patienten und MethodenFünfzig Augen wurden durch drei Ophthalmologen standardisiert untersucht. Bei allen Patienten wurde ein kompletter Augenstatus erhoben. Es wurden je drei Vorderabschnittsaufnahmen horizontal und vertikal erstellt. Während beim Visante-OCT die Auswertung mit einem im Gerät integrierten manuellen Auswertemodus erfolgte, wurde beim SL-OCT die am besten zentrierte Aufnahme mittels manuell zu bedienender Software (EyelabGlobal/4Optics) und digitaler, semiautomatischer Software (HEYEX) evaluiert. Verglichen wurden die zentrale Hornhautdicke (CCT), die Vorderkammertiefe (VKT), der Pupillendurchmesser (PD) sowie der Kammerwinkel-Kammerwinkel-Abstand (KW-KW).ErgebnisseGerätevergleich: Der horizontale Kammerwinkel-Kammerwinkel-Abstand (KW-KW) betrug beim Visante-OCT 11,65±0,47xa0mm und beim SL-OCT mit 12,0±0,57xa0mm (n=33, p=0,002). Vergleichende Vertikalscans waren nur bei 10 Augen möglich. Die zentrale Hornhautdicke betrug im Horizontalscan mit dem Visante-OCT 568±61xa0µm, mit dem SL-OCT 581±48xa0µm (n=35, p=0,03); im Vertikalscan mit dem Visante-OCT 565±62xa0µm und mit dem SL-OCT 568±51 µm (n=27, n.s.). Die Abweichungen beider Messmethoden schwanken im Horizontalscan zwischen −54,7 und 80,8xa0µm und im Vertikalscan zwischen −84,9 und 91,1xa0µm um die mittlere Differenz beider Messmethoden.n Analyseprogramm-Vergleich: Beim Horizontalscan korrelierte die manuelle Analyse mit der semiautomatischen bei der CCT 581±51xa0µm vs. 572±53xa0µm (r=0,903), bei der VKT 2,89±0,74xa0mm vs. 2,95±0,72xa0mm (r=0,98), beim PD 5,22±2,12xa0mm vs. 5,14±1,91xa0mm (r=0,917) und beim KW-KW 11,59±1,02xa0mm vs. 11,79±0,60xa0mm (r=0,47). Die manuelle und semiautomatische Auswertung von CCT und VKT unterschieden sich signifikant (p<0,026). Beim Vertikalscan korrelierte die manuelle Analyse mit der semiautomatischen bei der CCT 578±65xa0µm vs. 573±63xa0µm (r=0,593), bei der VKT 3,04±0,83xa0mm vs. 3,03±0,75xa0mm (r=0,92), beim PD 5,28±1,99xa0mm vs. 5,45±2,00xa0mm (r=0,899) und beim KW-KW mit 11,75±0,66xa0mm vs. 11,82±0,60xa0mm (r=0,537).SchlussfolgerungenIm Vergleich zum Vertikalscan erlaubt ein Horizontalscan zumeist die Untersuchung des gesamten Hornhaut-Vorderkammer-Iris-Segmentes inklusive Kammerwinkel. Hierzu stehen OCT zur Visualisierung und Biometrie des vorderen Augenabschnitts zur Verfügung, die mittels der Non-Contact-Methode einfach zu bedienen sind. Die untersuchten Geräte zeigen eine eingeschränkte Vergleichbarkeit.Mit der manuell zu bedienenden EyelabGlobal-Analyse war im Vergleich zum semiautomatischen HEYEX eine Untersuchung aller Augen möglich. Beide Softwaresysteme ermöglichen vergleichbare Vorderabschnittsmessungen. Der semiautomatische Biometriemodus kann die Auswertungszeit auf 10% reduzieren, setzt allerdings exzellente und gut zentrierte SL-OCT-Scans voraus.AbstractBackgroundDigital visualisation of the anterior eye segment is becoming more and more important. Two commercially available optical coherence tomographs (OCTs) — Visante OCT (Carl-Zeiss Meditec Jena) and Slit Lamp-OCT (SL-OCT. Heidelberg Engineering) — were evaluated. Additionally, a manual and a semiautomatic analysis mode for the anterior segment biometry were compared using the SL-OCT.Patients and methodsFifty eyes were examined by three ophthalmologists with complete eye status in a standardised fashion. Three anterior segment scans (horizontal and vertical) were performed using the Visante OCT and the SL-OCT. The manual integrated analysis mode of the Visante OCT was used. The best centred SL-OCT scan was analysed with a manual (EyelabGlobal/4Optics) and a semiautomatic procedure (HEYEX). Central corneal thickness (CCT), anterior chamber depth (ACD), pupillary diameter (PD) and chamber angle–angle distance (CAAD) were compared.ResultsComparison of Visante OCT and SL-OCT: The horizontal CAAD was 11.65±0.47xa0mm for the Visante-OCT and 12.0±0.57xa0mm for the SL-OCT (p=0,002), vertical scans were comparable in 10xa0eyes only. The CCT was 568±61 µm with the Visante-OCT and 581±48 µm with the SL-OCT (n=35, p=0.03) in horizontal scans and 565±62 µm with the Visante-OCT and 568±51 µm with the SL-OCT in vertical scans (n=27, not significant). Deviation of the two measurement methods varied between –54.7 and 80.8 µm in horizontal scans and between –84.9 and 91.1 µm in vertical scans from the mean difference of the two methods.n Comparison of the analysis programs: Horizontal scans: Manual analysis correlated with semiautomatic analysis in CCT as 581±51 µm vs. 572±53 µm (r=0.903), ACD 2.89±0.74xa0mm vs. 2.08±0.72xa0mm (r=0.98), PD 5.22±2.12xa0mm vs. 5.14±1.91xa0mm (r=0.917) and CAAD 11.59±1.02xa0mm vs. 11.79±0.6xa0mm (r=0.47). The manual and a semiautomatic analysis modes for CCT and ACD differed significantly (p<0.026). Vertical scan: Manual versus semiautomatic analysis modes correlated in CCT as 578±65 µm vs. 573±63 µm (r=0.593), ACD with 3.04±0.83xa0mm vs. 3.03±0.75xa0mm (r=0.92), PD with 5.28±1.99xa0mm vs. 5.45±2.00xa0mm (r=0.899) and CAAD with 11.75±0.66xa0mm vs. 11.82±0.6xa0mm (r=0.537).ConclusionsA near complete investigation of the cornea–anterior–chamber–iris segment is provided by the horizontal scan compared with the vertical scan. The noncontact OCT method is an easily handled tool for visualisation and biometry of the anterior eye segment. The investigated OCTs show a limited comparability.A complete analysis was possible in all eyes with the EyelabGlobal system in contrast to the HEYEX analysis software. Both analysis programs provided comparable measurements of the anterior eye segment. The semiautomatic biometrical mode may reduce the analysis time in qualitative excellent and well-centred scans to 10%.BACKGROUNDnDigital visualisation of the anterior eye segment is becoming more and more important. Two commercially available optical coherence tomographs (OCTs) - Visante OCT (Carl-Zeiss Meditec Jena) and Slit Lamp-OCT (SL-OCT. Heidelberg Engineering) - were evaluated. Additionally, a manual and a semiautomatic analysis mode for the anterior segment biometry were compared using the SL-OCT.nnnPATIENTS AND METHODSnFifty eyes were examined by three ophthalmologists with complete eye status in a standardised fashion. Three anterior segment scans (horizontal and vertical) were performed using the Visante OCT and the SL-OCT. The manual integrated analysis mode of the Visante OCT was used. The best centred SL-OCT scan was analysed with a manual (EyelabGlobal/4Optics) and a semiautomatic procedure (HEYEX). Central corneal thickness (CCT), anterior chamber depth (ACD), pupillary diameter (PD) and chamber angle-angle distance (CAAD) were compared.nnnRESULTSnComparison of Visante OCT and SL-OCT: The horizontal CAAD was 11.65+/-0.47 mm for the Visante-OCT and 12.0+/-0.57 mm for the SL-OCT (p=0,002), vertical scans were comparable in 10 eyes only. The CCT was 568+/-61 microm with the Visante-OCT and 581+/-48 microm with the SL-OCT (n=35, p=0.03) in horizontal scans and 565+/-62 microm with the Visante-OCT and 568+/-51 microm with the SL-OCT in vertical scans (n=27, not significant). Deviation of the two measurement methods varied between -54.7 and 80.8 microm in horizontal scans and between -84.9 and 91.1 microm in vertical scans from the mean difference of the two methods. Comparison of the analysis programs: Horizontal scans: Manual analysis correlated with semiautomatic analysis in CCT as 581+/-51 microm vs. 572+/-53 microm (r=0.903), ACD 2.89+/-0.74 mm vs. 2.08+/-0.72 mm (r=0.98), PD 5.22+/-2.12 mm vs. 5.14+/-1.91 mm (r=0.917) and CAAD 11.59+/-1.02 mm vs. 11.79+/-0.6 mm (r=0.47). The manual and a semiautomatic analysis modes for CCT and ACD differed significantly (p<0.026). Vertical scan: Manual versus semiautomatic analysis modes correlated in CCT as 578+/-65 microm vs. 573+/-63 microm (r=0.593), ACD with 3.04+/-0.83 mm vs. 3.03+/-0.75 mm (r=0.92), PD with 5.28+/-1.99 mm vs. 5.45+/-2.00 mm (r=0.899) and CAAD with 11.75+/-0.66 mm vs. 11.82+/-0.6 mm (r=0.537).nnnCONCLUSIONSnA near complete investigation of the cornea-anterior-chamber-iris segment is provided by the horizontal scan compared with the vertical scan. The noncontact OCT method is an easily handled tool for visualisation and biometry of the anterior eye segment. The investigated OCTs show a limited comparability. A complete analysis was possible in all eyes with the EyelabGlobal system in contrast to the HEYEX analysis software. Both analysis programs provided comparable measurements of the anterior eye segment. The semiautomatic biometrical mode may reduce the analysis time in qualitative excellent and well-centred scans to 10%.


Ophthalmologe | 2008

Schwere Bulbus eröffnende Augenverletzungen

W.F. Schrader; A. Viestenz

In spite of the technical progress in vitreoretinal surgery, the anatomical and functional results of severe ocular injuries involving the posterior segment are still discouraging. Perforating injuries and ruptures that extend posterior to the muscle insertions have the worst outcomes. When the secondary intervention is usually performed between days 7 and 14 post trauma, it is not unlikely that a severe proliferative vitreoretinopathy has already occurred. With a new concept--to act rather than to react to alterations secondary to severe posterior segment trauma--the functional results of these injuries may be further improved, according to various studies. The internal reconstruction is in part performed together with the primary wound closure, or, alternatively, within 100 h after the trauma. This idea is currently being further evaluated in a prospective multicenter multinational study conducted by the World Eye Injury Register.ZusammenfassungTrotz der enormen technischen Fortschritte der vitreoretinalen Mikrochirurgie sind die Ergebnisse nach schweren Augapfel eröffnenden Verletzungen, v.xa0a. perforierenden Verletzungen und Rupturen mit Beteiligung postäquatorialer Strukturen, unbefriedigend. Dabei spielt die sehr früh einsetzende proliferative Vitreoretinopathie (PVR), die schon in den ersten Tagen zu Traktionsmembranen und Netzhautablösungen führt, eine wichtige Rolle. Wird die sekundäre interne Rekonstruktion in der 2. posttraumatischen Woche vorgenommen, trifft man oft auf eine nur noch schwer zu beherrschende PVR-Ablatio. Laut neueren Studien können die anatomischen und funktionellen Ergebnisse verbessert werden, wenn die zu erwartende Komplikation bereits vorbeugend chirurgisch angegangen wird. Dabei wird die interne Rekonstruktion z. T. bei der primären Wundeversorgung vorgenommen, spätestens jedoch innerhalb einer 100-h-Frist. Dieses Vorgehen wird zurzeit in einer weltweiten multizentrischen Beobachtungsstudie prospektiv untersucht.AbstractIn spite of the technical progress in vitreoretinal surgery, the anatomical and functional results of severe ocular injuries involving the posterior segment are still discouraging. Perforating injuries and ruptures that extend posterior to the muscle insertions have the worst outcomes. When the secondary intervention is usually performed between days 7 and 14 post trauma, it is not unlikely that a severe proliferative vitreoretinopathy has already occurred. With a new concept – to act rather than to react to alterations secondary to severe posterior segment trauma – the functional results of these injuries may be further improved, according to various studies. The internal reconstruction is in part performed together with the primary wound closure, or, alternatively, within 100xa0h after the trauma. This idea is currently being further evaluated in a prospective multicenter multinational study conducted by the World Eye Injury Register.


Klinische Monatsblatter Fur Augenheilkunde | 2008

Traumatic Endophthalmitis Prevention Trial (TEPT)

A. Viestenz; W. Schrader; W. Behrens-Baumann

AIMnPost-traumatic endophthalmitis is one of the most severe complications occurring in 2-17% after open globe injuries. Early intravenous antibiotics may minimise the risk of post-traumatic endophthalmitis. The design of a new study to evaluate the role of an additional intravitreal antibiotic injection in the prevention of post-traumatic endophthalmitis is presented in this paper.nnnPATIENTS AND METHODSnA prospective, multicentre, randomised controlled study was designed. Patients with penetrating or perforating eye injuries will be included up to the year 2010. The wound closure and IOFB (intraocular foreign body) removal must be performed within 24 hours after the trauma. After grouping into low risk (e. g., metallic IOFB) or high risk patients (e. g., agricultural trauma, organic IOFB) each patient will be randomised for 1) intravenous moxifloxacin only or 2) intravenous moxifloxacin plus intravitreal 1 mg Vancomycin plus 2.25 mg [DOSAGE ERROR CORRECTED] Ceftazidim.nnnRESULTSn17 European Departments of Ophthalmology have agreed to participate. The rate of post-traumatic endophthalmitis in each group will be statistically compared. The follow-up period of this study will last 6 months.nnnCONCLUSIONnOther Departments of Ophthalmology are invited to join the TEPT.

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W. Behrens-Baumann

Otto-von-Guericke University Magdeburg

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Achim Langenbucher

University of Erlangen-Nuremberg

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B. Seitz

University of Erlangen-Nuremberg

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S. Walter

Otto-von-Guericke University Magdeburg

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Synke Meltendorf

Otto-von-Guericke University Magdeburg

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Christian K. Vorwerk

Otto-von-Guericke University Magdeburg

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Kelly D. Hirschfeld

Otto-von-Guericke University Magdeburg

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Matthias Evert

Otto-von-Guericke University Magdeburg

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