Manfred R. Tetz

Photographic image analysis system of posterior capsule opacification.

Purpose: To describe a morphological scoring system of posterior capsule opacification (PCO) that is not based on visual acuity testing. Setting: Department of Ophthalmology, University of Heidelberg, Germany. Methods: Following dilation of the pupil, standardized photographs of the pseudophakic anterior segments were obtained using a photo slitlamp. Posterior capsule opacification was scored by evaluating retroillumination photographs. The individual PCO score was calculated by multiplying the density of the opacification (graded from 0 to 4) by the fraction of capsule area involved behind the intraocular lens (IOL) optic. To evaluate the reliability of the morphological scoring system, six observers examined photographs of five eyes each (Experiment A, interindividual reliability). The same observer scored the PCO in three eyes on five different days (Experiment B, intraindividual reliability). Results: Morphological PCO scores were very reliable. With PCO scoring from 0 to 4, the interindividual reliability showed standard deviations between 0.08 and 0.25. The intraindividual reliability showed standard deviations between 0.06 and 0.19 of the mean individual PCO scores. Standard deviation was 0.12 when different photographs of the same eye were scored. Conclusion: The morphological scoring system evaluates the entire area behind the IOL optic and thus includes a larger area of the posterior capsule than does visual acuity testing. The method revealed high reliability and insignificant investigatordependent variations. When using a standardized photographic setup, systematic errors by the photographic technique were not relevant. This method may be an important tool to accurately test for differences in PCO formation with various IOL styles and surgical methods.

Measuring anterior chamber depth with the Orbscan Topography System

Purpose: To assess the reliability of the Orbscan Topography System in measuring anterior chamber depth (ACD). Setting: Department of Ophthalmology, Ruprecht‐Karls‐University of Heidelberg, Heidelberg, Germany. Methods: The Orbscan Topography System is a 3‐D, scanning slit beam system for analyzing corneal surfaces as well as structures of the anterior segment, e.g., iris, lens. Reflected surface data points are measured in the x, y, and z axes, creating color‐coded true surface topography maps. We measured ACID prior to cataract surgery in 56 eyes of 37 patients (mean age 70.4 years + 13.2 [SD]) using the Orbscan system and, as a control, the Grieshaber Biometric System (ultrasound) and the Jager ACD slitlamp measurement system. Results: Mean ACD values measured with the Orbscan system were 3.23 0.55 mm; ultrasound measurements were 3.27 ± 0.54 mm and Jäger measurements, 3.10 ± 0.55 mm. The average difference between Orbscan and ultrasound values was 0.04 ± 0.15 mm. The correlation coefficient between Orbscan and ultrasound was 0.96 (P < .00001) and between Orbscan and Jäger, 0.899 (P < .0001). Conclusion: The ACID measurements by the Orbscan system were equivalent to common reference measurements.

Inhibition of posterior capsule opacification by an intraocular-lens-bound sustained drug delivery system: An experimental animal study and literature review

Purpose: To find a way to prevent or significantly reduce posterior capsule opacification (PCO) with modern phacoemulsification and in‐the‐bag intraocular lens (IOL) implantation. Setting: Department of Ophthalmology and Institute for Pharmaceutical Technology and Biopharmacy, Ruprecht‐Karls‐University of Heidelberg, Germany. Methods: We evaluated the effects of an IOL‐bound sustained drug delivery system (SDDS) consisting of the carrier substance poly‐DL‐lactid and the drug daunorubicin or indomethacin. The system was applied to the IOL surface and implanted in rabbit eyes. At 8 weeks postoperatively, PCO wet mass was determined. Toxic and inflammatory effects were documented by histopathology. Results: The average PCO wet mass was 54.6 mg in the control group, 28.6 mg with daunorubicin, and 64.1 mg with indomethacin. Statistical analysis showed a significant reduction of PCO with daunorubicin (Mann‐Whitney U‐test, P = .025) and no PCO‐reducing effect with indomethacin. Light microscopy of the specimens revealed mild inflammation, especially at the limbus, and some endothelial cell loss in the daunorubicin group and iris and ciliary body inflammation in the indomethacin group. Conclusion: In the rabbit eye, slow release of daunorubicin reduced PCO formation by approximately 50%. It must be determined whether the endothelial side effects are specific to the rabbit species or whether the human cornea is as sensitive. The principle of the IOL‐bound SDDS and the evaluation procedure can be standardized and used for systematic tests in the future.

Relative anterior microphthalmos: morphometric analysis and its implications for cataract surgery.

PURPOSE To evaluate morphometric data and risk factors for complications of cataract surgery in patients with relative anterior microphthalmos (RAM). DESIGN Retrospective, comparative study (Part I) and matched pairs analysis with controls (Part II). PARTICIPANTS Sixty-two patients with RAM who underwent cataract surgery at the Department of Ophthalmology, Ruprecht-Karls-University of Heidelberg, Germany, between 1989 and 1997. RAM is defined as eyes with horizontal corneal diameters </=11 mm, axial length of >20 mm, and no other morphologic malformation. MAIN OUTCOME MEASURES Part I: Patients were examined preoperatively for anterior chamber (AC) depth, lens thickness, total axial length, and refraction. Associated ocular pathologic conditions (such as glaucoma or previous surgical interventions) were recorded. Part II: A matched pairs analysis concerning the anatomic features was performed with a group of 17 patients with RAM and 17 patients (controls) that matched the RAM group in terms of axial length, age, and gender but showed corneal diameters >11 mm. RESULTS Part I: Anatomic parameters in RAM showed an average corneal diameter of 10.7 +/- 0.34 mm, AC depth of 2.20 +/- 0.49 mm, and average lens thickness of 5. 05 +/- 0.45 mm. Fifty-five percent of the patients had myopic refraction. There was a high incidence of glaucoma (77.4%), cornea guttata (45.2%), and pseudoexfoliation syndrome (16.1%) in the RAM group. Sixty percent of patients had undergone previous glaucoma surgery. After cataract surgery, 51.2% of patients achieved a visual acuity of >20/40 and 69.8% of >20/50. Temporary corneal edema (54. 8%) and ciliolenticular block (11.6%) were the most important complications after cataract surgery. Part II: Matched pairs analysis showed significant differences between RAM and controls in terms of AC depth (P =0.029) but no difference in lens thickness (P = 0.12). CONCLUSIONS Relative anterior microphthalmos can be characterized in terms of morphometric data as eyes with corneal diameters </=11 mm and AC depths of 2 mm. The small anterior segment, especially the shallow anterior chamber, is responsible for the high incidence of glaucoma and postoperative complications after cataract surgery. Identifying these patients before surgery helps the cataract surgeon to be prepared for potential problems.

Treatment of traumatic cataracts

Purpose: To analyze the postoperative outcome and complication rate following cataract extraction because of post‐traumatic lens opacification. Setting: University medical center. Methods: A retrospective analysis was done of 148 eyes with traumatic cataracts operated on between 1978 and 1992. Age, sex, traumatic sequelae, surgical strategies, and postoperative complications were reviewed for all eyes. Results: In 85 eyes, Group A, a history of blunt trauma could be ascertained. In 63 eyes, Group B, there had been a penetrating injury. Secondary glaucoma was observed more frequently in patients with blunt trauma. A posterior chamber intraocular lens was implanted in 85% of Group A eyes and in 67% of Group B eyes. Mild or moderate postoperative complications occurred in 15% of all cases. Postoperatively, the incidence of glaucoma remained unchanged. Visual acuity improved in 90% of eyes. Ten percent of eyes did not benefit from cataract surgery because of severe traumatic involvement of the retina or optic nerve. Conclusions: In this study, a majority of eyes with traumatic cataract were safely rehabilitated with posterior chamber lens implantation. Visual acuity improved in 90% of eyes; complications were seen in 15%.

Cataracta complicata bei verschiedenen Formen der Retinitis pigmentosa Art und Häufigkeit

Purpose: To study the incidence and types of cataract in retinitis pigmentosa (RP) and their variations among different forms of RP.Patients and methods: This analysis was based on data from 473 patients with RP (autosomal dominant, n=87; autosomal recessive, n=79; x chromosomal recessive, n=23; simplex RP, n=215; Ushers syndrome n=80; M. Refsum and others, n=9) that were retrieved from the literature and patient charts in our clinic.Results: Posterior subcapsular cataract (PSC) developed with the following frequencies for the different genetic types of RP: autosomal dominant, 45.3%; autosomal recessive, 44.0%; x chromosomal recessive, 40.7%; simplex RP, 46.1%; Ushers syndrome, 52.9%. PSC was the only type of lens opacity in patients with Ushers syndrome and autosomal recessive RP. PSC development correlated with early onset of RP symptoms. Nuclear cataracts showed a statistically significant higher frequency in patients with simplex RP (14.8%) than in other genetic types (0–5.9%) (P<0.01). In addition, nuclear cataracts developed in simplex RP at a significantly later age (69.6±12.4 years) than PSC (44.4±12.3 years) (P<0.001). Patients with cataracts showed significantly worse visual fields than patients with clear lenses (P=0.00067).Conclusions: The typical RP cataract (PSC) was found in similar frequencies among all genetic types of RP. PSC was the only type of lens opacity in patients with Ushers syndrome and autosomal recessive RP. Nuclear cataracts developed on average 20 years later than PSC and had their highest incidence in patients with simplex RP. Patients with cataracts showed significantly worse visual field results, indicating a more pronounced retinal pathology.Hintergrund: Ziel dieser Studie war es, die Häufigkeit und die Art der Katarakt bei Retinitis pigmentosa (RP) und deren Ausprägung bei den verschiedenen Vererbungsformen der RP zu untersuchen.Patienten und Methode: Zur Auswertung kamen Daten von insgesamt 473 Patienten mit RP (autosomal-dominant n=87, autosomal-rezessiv n=79, X-chromosomal-rezessiv n=28, Simplex-RP n=215, Usher-Syndrom n=60, Morbus Refsum u.a. n=9), die aus der Literatur und aus dem eigenen Patientenkollektiv zusammengestellt wurden.Ergebnisse: Für die für RP typische Trübungsform der Cataracta subcapsularis posterior (PSC) fand sich folgende Häufigkeitsverteilung: autosomal-dominant 45,3%, autosomal-rezessiv 44,0%, X-chromosomal-rezessiv 40,7%, Simplex-RP 46,1%, Usher-Syndrom 52,9%. Bei den Patienten mit Usher-Syndrom und autosomal-rezessiver RP war die PSC die einzige Trübungsform. Kerntrübungen traten bei Patienten mit Simplex-RP signifikant häufiger auf (14,8%) als bei den anderen Vererbungsformen (0–5,9%, p<0,001). Des weiteren zeigte sich, daß Kerntrübungen bei Simplex-Patienten in einem signifikant höheren Lebensalter (69,6±12,4 Jahre) auftraten als eine PSC (44,4±12,3 Jahre; p<0,001). Patienten mit Katarakt zeigten zudem signifikant schlechtere Gesichtsfeldbefunde als Patienten ohne Katarakt (p=0,00067).Schlußfolgerungen: Die RP-typische Cataracta subcapsularis posterior kommt bei den verschiedenen Vererbungsmodi in ähnlicher Häufigkeit vor. Bei den hier geprüften Patienten mit Usher-Syndrom und autosomal-rezessiver RP war die PSC sogar die einzige erfaßte Trübungsform. Kerntrübungen bei RP traten erst in höherem Alter auf und waren am häufigsten mit der Simplex-Form assoziiert. Patienten mit Kataraktausbildung zeigten zusätzlich deutlich schlechtere Gesichtsfeldbefunde, was ein Hinweis für eine stärker ausgeprägte retinale Pathologie in dieser Gruppe ist.

Posterior capsule opacification and problems of Nd:YAG laser capsulotomy in retinitis pigmentosa

Background: Retinitis pigmentosa (RP) is associated with the development of a posterior subcapsular cataract (PSC). The development of posterior capsule opacification (PCO) after cataract surgery and a decrease of central visual acuity is sometimes misinterpreted by the patients as natural course of RP. Therefore, therapeutic intervention is often delayed. Patients and methods: In a retrospective study (part 1) the incidence of PCO was evaluated in a group of 26 RP patients who underwent cataract surgery and IOL implantation. In a prospective analyse (part 2) PCO was quantified in 13 RP patients using the standardized photographic technique and image analysis system introduced by Tetz et al. Matched pairs were formed with a control group of 13 patients without retinal disease who matched the RP group in terms of age distribution and postoperative follow-up time. In part 3 the parameters of Nd:YAG laser capsulotomy in 12 RP patients and 14 controls were evaluated. Results: Part 1: The cumulative PCO rate in RP at the end of the first postoperative year was 14.6 %, 26.8 % in the second, 53.7 % in the third and 70.7 % after the third year. Nd:YAG laser capsulotomy was performed in 70 % of eyes (after 18.4 ± 14.7 months). In eyes with significant PCO development 70 % had PSC preoperatively, while in eyes without PCO formation only 41.7 % showed PSC. Part 2: The matched pairs analysis showed a significantly higher PCO value for RP patients (2.11 ± 1.42) than for the control group (0.89 ± 0.72) (P = 0.038). Part 3: Average Nd:YAG laser energy levels were 12.8 ± 11.2 MJ (RP) and 7.6 ± 6.7 MJ (control). Some 25 % of RP patients required further laser treatment of regrown secondary cataract. Conclusions: Patients with RP showed a significantly higher incidence and density of PCO. Whether RP-specific pathomechanisms are responsible for this needs further investigation.Hintergrund: Patienten mit Retinitis pigmentosa (RP) entwickeln schon in jungen Jahren eine Cataracta complicata. Nach erfolgter Kataraktoperation wird die Ausbildung einer Cataracta secundaria und ein damit einhergehender Visusabfall von den Patienten häufig dem Verlauf der RP zugeordnet und die Möglichkeit einer therapeutischen Intervention nicht bedacht. Patienten und Methoden: Die Nachstarinzidenz wurde im Teil 1 der Studie retrospektiv bei 41 Augen von 26 RP-Patienten, die eine postoperative Nachbeobachtungszeit von mindestens 3 Monaten aufwiesen, untersucht. Im Teil 2 dieser Studie wurde bei 13 RP-Patienten mit dem Nachstar-Bildanalyse-System nach Tetz die Nachstarausprägung quantifiziert und in einem Paarvergleich mit einer Kontrollgruppe von 13 netzhautgesunden Patienten verglichen. Im Teil 3 wurden die Energiemengen zur Nd:YAG-Laser Kapsulotomie von 12 RP-Patienten und 15 netzhautgesunden Patienten verglichen. Ergebnisse: Teil 1: Die kumulative Nachstarrate der RP-Patienten betrug im ersten postoperativen Jahr 14,6 %, im zweiten 26,8 %, im dritten 53,7 % und erreichte bei den Patienten, mit einem Nachbeobachtungszeitraum > 36 Monaten, 70,7 %. Bei 70 % der Augen mit Nachstar mußte eine Nd: YAG-Laser Kapsulotomie durchgeführt wurde (nach 18,4 ± 14,7 Monaten). 70 % der Augen der Nachstargruppe zeigten als Kataraktform die typische subkapsuläre posteriore Katarakt, während diese in der Gruppe ohne Nachstarbildung nur in 41,7 % vorlag. Teil 2: der gematchte Paarvergleich zeigte für die RP-Patienten mit einem Nachstarwert von 2,11 ± 1,42 einen signifikant höheren Wert als die Kontrollgruppe (0,89 ± 0,72) (p = 0,038). Teil 3: Die durchschnittliche Nd:YAG-Laserenergiemenge betrug für die Gruppe der RP-Patienten 12,8 ± 11,2 mJ, für die Vergleichsgruppe 7,6 ± 6,7 mJ. 25 % der RP-Patienten mußten nachgelasert werden. Schlußfolgerungen: Patienten mit Retinitis pigmentosa weisen eine signifikant höhere Nachstarrate und Nachstarausprägung auf, die sich auch klinisch in einen höheren Energiebedarf bei der Nd:YAG-Laserkapsulotomie ausdrückt. Ob RP-spezifische Pathomechanismen hierfür verantwortlich sind, läßt sich z. Z. noch nicht abschließend beurteilen. Hierfür sind weitere Studien notwendig.

Clinicopathological finthngs in human autopsy eyes with an Anis circular lens

Purpose: To evaluate the long‐term performance of the Anis circular intraocular lens (IOL). Setting: Center for IOL Research, Storm Eye Institute, Charleston, South Carolina. Materials: Fifteen human autopsy eyes with an Anis circular IOL submitted between 1985 and 1993 were evaluated. The eyes were sectioned at the equatorial plane, and the anterior segment containing the capsular bag and the IOL was photographed from the posterior perspective. Fixation, centration, capsular bag shape, zonular damage, central posterior capsule opacification (PCO), and Soemmering’s ring formation were analyzed. The results were compared with those of a control group comprising human autopsy eyes with a one‐piece (n = 15) or three‐piece (n = 15) poly(methyl methacrylate) IOL with a C‐loop design. Results: All 15 Anis IOLs showed symmetrical in‐the‐bag fixation. Mean decentration in the Anis IOL eyes was significantly lower than in the control eyes (P = .02). Eyes with the Anis IOL had fewer zonular defects (P = .0005) and a better circular extension of the capsular bag (P = .003). There were no statistically significant differences in PCO (P = .29) or Soemmering’s ring formation (P = .67). Conclusion: The Anis IOL with a circular haptic design had better centration and capsular bag morphology than the control eyes, although a difference in PCO and Soemmering’s ring formation could not be shown.

Cataracta secundaria : Analyse der Energiemengen zur Nd:YAG-Laserkapsulotomie

Hintergrund: Die Ausbildung der Cataracta secundaria wird von einer Vielzahl von Faktoren wie Linsenmaterial und -design, Alter, Nachbeobachtungszeitraum sowie okulären und systemischen Erkrankungen beeinflußt. Inwiefern sich diese Faktoren klinisch auf die am Nd:YAG-Laser benutzten Energiemengen auswirken, ist Gegenstand dieser Untersuchung. Patienten und Methoden: Bei 172 Patienten im Alter von 67,3±15,9 Jahren wurden Daten zur Nd:YAG-Laser Kapsulotomie ausgewertet. Untersucht wurden der Einfluß von Alter, Post-OP-Zeitraum, Linsenfixation und verschiedener okulärer Erkrankungen auf Gesamtenergiemengen und Re-Nd:YAG-Rate. 69/172 der Patienten (=43,7%) zeigten keine weiteren okulären Pathologien (=Normalpatienten), bei 24/172 (=15,2%) lag ein Glaukom, bei 14/172 (=8,9%) eine diabetische Retinopathie, bei 12/172 (=7,6%) eine Retinitis pigmentosa, bei 8/172 (=5,1%) eine Myopia magna, bei 7/172 (=4,4%) ein Z.n. Triple Procedure mit KPL vor. 24/172 (=15,2%) zeigten verschiedene zusätzliche okuläre Erkrankungen (z.B. PEX) und wurden in der Gruppe “Sonstige” zusammengefaßt. Die Patienten sind im Zeitraum von 1988 bis 1995 kataraktoperiert und mit PMMA-Hinterkammerlinsen versorgt worden. Ergebnisse: Die Nd:YAG-Laser-Kapsulotomien erfolgten 28,2±17,7 Monate nach Kataraktoperation. Die Gesamtenergiemenge betrug für alle Patienten 12,7±9,4 mJ. Der Visus vor der Laserbehandlung betrug 0,3±0,2. Bei den Normalpatienten fand sich keine Korrelation zwischen Gesamtenergie und Post-OP-Dauer oder Patientenalter (p>0,43). Bei 26 Patienten erfolgte eine zweite Nd:YAG-Laser-Kapsulotomie zur Erweiterung der vorbestehenden Lücke. Hier zeigten Patienten mit Retinitis pigmentosa eine signifkant höhere Re-YAG-Rate als die übrigen Patientengruppen (p=0,00059). Der Vergleich von sulkus- versus kapselsackfixierten HKL zeigte, daß bei Augen mit sulkusfixierten Linsen früher und mit höheren Energiemengen gelasert wurde. Schlußfolgerungen: Die verschiedenen okulären Erkrankungen des vorderen und hinteren Augenabschnittes zeigen ein unterschiedliches Profil bezüglich der Energiemengen und der Re-YAG-Laserraten. Patienten mit Retinitis pigmentosa zeigten eine signifikant höhere Re-YAG-Rate. Sulkusfixation einer HKL resultierte in früheren Kapsulotomien und höheren Energiemengen im Vergleich zur Kapselsackfixation.Background: Formation of secondary cataract is influenced by various factors, such as IOL material, IOL design, age, follow-up time and ocular and systemic diseases. It has not yet been studied whether these factors have an clinical impact on the energy used for Nd:YAG laser capsulotomy. Patients and methods: We examined 172 patients, aged 67.3±15.9 years, concerning energy levels required for Nd:YAG laser capsulotomy. We analysed the influence of age, implant duration, IOL fixation and ocular conditions on total energy and repetition rate of Nd:YAG laser capsulotomy. Sixty-nine patients (43.7%) had no other ocular pathology (control), 24 (15.2%) glaucoma, 14 (8.9%) diabetic retinopathy, 12 (7.6%) retinitis pigmentosa, 8 (5.1%) high myopia, 7 (4.4%) triple procedure with perforating keratoplasty. Twenty-four (15.2%) presented with various additional ocular conditions such as pseudoexfoliation syndrome. Patients had undergone cataract surgery between 1988 and 1995 with implantation of PMMA-IOLs. Results: Nd:YAG laser capsulotomies were performed on average 28.2±17.7 months postoperatively. The average total energy used was 12.7±9.4 mJ. Visual acuity (Pre-YAG) was 0.3±0.2. In the control group there was no correlation between energy and implant duration or age (P>0.43). 26 patients required a second Nd:YAG laser capsulotomy. Patients with retinitis pigmentosa showed a significantly higher re-YAG rate than the other patient groups (P=0.00059). In eyes with sulcus fixation of the IOL, capsulotomies were performed earlier and with higher energy levels than for in-the-bag fixation. Conclusions: The different ocular conditions of the anterior and posterior segment showed a different profile for Nd:YAG laser capsulotomy energy level and Nd:YAG laser repetition rate. Sulcus fixation of an IOL resulted in earlier capsulotomies with higher energy levels.

Entwicklung eines standardisierten Bewertungsschemas der Cataracta complicata bei Retinitis pigmentosa

Einleitung: Alle Formen der Retinitis pigmentosa (RP) sind mit der Ausbildung eine Cataracta complicata, meist in Form einer posterioren subkapsulären Katarakt (PSC) assoziiert. Wegen der häufig nur einen kleinen Teil der Linse betreffenden Trübungsform fällt die Graduierung der PSC und die Indikationsstellung zur Kataraktoperation oftmals schwer.Patienten und Methode: Die Methode wurde in Analogie zu einem standardisierten Nachstarbewertungsschema nach Tetz entwickelt. Bei maximaler medikamentöser Mydriasis wurden Vorderabschnittsaufnahmen im regredienten Licht an einer Zeiss®-Photospaltlampe Modell 40 SL/P angefertigt. Für jedes Auge wurde ein Kataraktindex ermittelt, der sich aus der Multiplikation von 2 Werten ergab: 1. Der Dichte der PSC (graduiert von 0 – 4), 2. des prozentualen Befalls der Fläche im zentralen Pupillarbereich (Durchmesser 4 mm) (als dezimaler Bruch). Zur Überprüfung der Reliabilität der Bewertungsmethode wurden in Teil 1 dieser Studie von 2 Untersuchern Aufnahmen von jeweils 11 Patientenaugen mit RP und unterschiedlich ausgeprägter PSC unabhängig voneinander ausgewertet. In Teil 2 dieser Studie wurden 37 Augen von 24 RP-Patienten im Alter von 47,2±11,8 Jahren ausgewertet und die Kataraktindizes mit verschiedenen Parametern (Visus, Alter, Gesichtsfeld, ERG-Befunde usw.) korreliert.Ergebnisse: Teil 1. Die Werte der Kataraktdichtegraduierung der 11 Patienten lagen zwischen 1 und 4. Bezogen auf den zentralen Pupillarbereich (Durchmesser 4 mm) waren zwischen 13 und 100% der Fläche betroffen. Die Kataraktindizes (Dichte×Areal) lagen insgesamt zwischen 0,13 und 4,0 (Mittelwerte: Untersucher 1: 1,41±1,49; Untersucher 2: 1,28±1,46; Untersucher 3: 1,22±1,44; Unterschiede nicht signifikant: p = 0,77). Teil 2. Bei den 24 Patienten lag bei einer durchschnittlichen Dauer der RP von 23 Jahren ein durchschnittlicher Kataraktindex von 1,72±1,35 vor. Es zeigten sich keine Korrelation der Kataraktausprägung zu ERG- oder GF-Befunden (r <0,2; p>0,4), hingegen eine gute Korrelation zum Visus (r = –0,72; p = 0,0001). Patienten mit Frühmanifestation der RP (vor 20. Lebensjahr) zeigten bei gleicher Verlaufsdauer der Erkrankung eine stärkere Kataraktausprägung (Kataraktindex: 2,06±1,67) als Patienten mit einer Spätmanifestation der RP (Kataraktindex: 0,61±0,44).Schlußfolgerung: Das Bewertungsschema erlaubt eine reproduzierbare Beurteilung der PSC bei RP-Patienten und kann als nützliche Hilfe zur Indikationsstellung der Kataraktoperation bei RP herangezogen werden.Introduction: Retinitis pigmentosa (RP) is associated with the formation of a posterior subcapsular cataract (PSC). As only a small part of the crystalline lens is usually affected, it is sometimes difficult to determine to what extent the visual loss is caused by the PSC alone.Patients and methods: The methodology was developed in analogy to a scoring system for posterior capsule opacification by Tetz et al. Following dilation of the pupil, standardized photographs of the anterior segments were obtained utilizing a Zeiss photoslitlamp model 40 SL/P. The PSC was scored by evaluating retroillumination photographs. The individual PSC index was calculated by multiplying the density of the opacification (graded from 0 to 4) by the area involved in the central 4 mm zone of the pupil (calculated between 0 and 1). For testing the reliability of the evaluation system in part 1 of this study, 11 RP patients with different grades of PSC were examined by three independent observers. In part 2 of this study 37 eyes of 24 RP patients, aged 47.2±11.8 years, were evaluated and the PSC index was correlated with different parameters (visual acuity, age, visual fields, eletroretinography).Results: Part 1. The cataract-density grades were between 1 and 4 in the 11 patients. In relation to the central 4-mm pupillary zone between 13 and 100% of the area were opacified. Cataract indices (density×area) were between 0.13 and 4.0 (Mean values: Examiner 1: 1.41±1.49; Examiner 2: 1.28±1.46; Examiner 3: 1.22±1.44; differences not significant: P = 0.77). Part 2. After an average duration of RP of 23 years, the average cataract index of the 24 patients was 1.72±1.35. There was no correlation between cataract index and ERG or visual fields (r<0.2; P>0.4); however, there was a good correlation to visual acuity (r = –0.72; P = 0.0001). Patients with early onset of RP (before 20th year of life) presented on average with an higher cataract index (2.06±1.67) compared to patients with late manifestation (0.61±0.44), but equivalent duration of RP.Conclusions: The evaluation system offers a reliable and reproducible method for measuring PSC density and extension in RP patients. The method can serve as a useful tool for documenting PSC development and help to define the indications for cataract surgery in RP.