Papers by Christoph Amstutz
Patient-Reported Outcome Measures (PROMs) with Refractive and Diffractive Extended Depth of Focus (EDOF) Intraocular Lenses
Klinische Monatsblätter für Augenheilkunde, Apr 1, 2024
Disease characteristics. VCAN-related vitreoretinopathy, which includes Wagner syndrome and erosi... more Disease characteristics. VCAN-related vitreoretinopathy, which includes Wagner syndrome and erosive vitreoretinopathy (ERVR), is characterized by "optically empty vitreous" on slit-lamp examination and avascular vitreous strands and veils, mild or occasionally moderate to severe myopia, presenile cataract, night blindness of variable degree associated with progressive chorioretinal atrophy, retinal detachment at advanced stages of the disease, and reduced visual acuity. Systemic abnormalities are not observed. The first signs usually become apparent during early adolescence, but onset can be as early as age two years. Diagnosis/testing. The clinical diagnosis of VCAN-related vitreoretinopathy is established based on typical clinical findings and a family history consistent with autosomal dominant inheritance. VCAN (previously CSPG2) is the only gene known to be associated with Wagner syndrome and ERVR. Molecular genetic testing is available on a clinical basis. Management. Treatment of manifestations: Refractive error is corrected by spectacles or contact lenses; visually disabling cataract is treated by cataract surgery, preferably by an experienced surgeon. Retinal breaks without retinal detachment are treated with laser retinopexy or cryocoagulation. Vitreoretinal surgery is indicated for retinal detachment, vitreoretinal traction involving the macula, or epiretinal membranes involving the macula. Surveillance: annual ophthalmologic examination by a vitreoretinal specialist. Testing of relatives at risk: for the purpose of early diagnosis and treatment of ophthalmologic complications in at-risk relatives: molecular genetic testing if the disease-causing mutation has been identified in the family; otherwise, ophthalmologic evaluation. Genetic counseling. VCAN-related vitreoretinopathy is inherited in an autosomal dominant manner. Most individuals diagnosed with VCAN-related vitreoretinopathy have an affected parent. Each child of an affected individual has a 50% chance of inheriting the mutation. Although no laboratories listed in the GeneTests Laboratory Directory offer molecular genetic testing for prenatal diagnosis of VCAN-related vitreoretinopathy, such
Preliminary results of aflibercept in treatment naïve choroidal neovascularization of neovascular age-related macular degeneration
Investigative Ophthalmology & Visual Science, Apr 30, 2014
The aim of this study was to evaluate the early response of aflibercept as first-line therapy in ... more The aim of this study was to evaluate the early response of aflibercept as first-line therapy in treatment-naive patients with newly diagnosed choroidal neovascularization (CNV) in age-related macular degeneration (AMD). An analysis of 35 eyes (35 patients, 28 female, 7 male) with treatment-naive active CNV was undertaken. Lesion activity was determined based on fluorescein angiography, clinical and optical coherence tomography (OCT) findings, including the presence of sub-, intraretinal fluid, retinal pigment epithelial (RPE) detachment and hemorrhage. Logarithm of the minimum angle of resolution (LogMAR) charts were used for testing best corrected or best available visual acuity (BCVA). Treatment response was evaluated based on changes in BCVA and lesion activity. Classic or predominantly classic CNV was diagnosed in 7 eyes (20.0%), occult or minimally classic in 21 eyes (60.0%), retinal angiomatous proliferation in 5 eyes (14.3%) and polypoidal choroidal vasculopathy in 2 eyes (5.7%). Lesion activity was evaluated as unchanged in only one eye. In all other eyes, a definite treatment response was observed with complete resolution of fluid in 20 eyes after a single injection. Three eyes did not show improved sub-RPE fluid with smaller pigment epithelial detachments. A rip of the RPE was seen in 3 eyes. All patients maintained vision, 7 patients (7 eyes) gained >15 letters from baseline to month 2 follow-up, of whom 4 reached this level of visual acuity after one injection. The visual acuity gains in this study were maintained through 6 months. There seems to be a rapid treatment response to aflibercept independent of the underlying CNV. Aflibercept may be beneficial even in eyes with large pigment epithelial detachments due to exudative AMD.
Normalization of Functional and Anatomic Changes in Carcinoma Associated Retinopathy
Investigative Ophthalmology & Visual Science, Apr 28, 2009
Langzeit-Verlauf bei Patienten mit intravitrealer Anti-VEGF Therapie für neovaskuläre AMD
Klinische Monatsblatter Fur Augenheilkunde, Apr 22, 2015
ABSTRACT Randomized controlled phase III studies have shown that intravitreal anti-VEGF therapy i... more ABSTRACT Randomized controlled phase III studies have shown that intravitreal anti-VEGF therapy is effective for exsudative age-related macular degeneration (AMD) over two years. Recently, the seven-year outcomes in ranibizumab-treated patients of the ranibizumab phase III studies have been published. Only a few other studies with such a long follow-up for intravitreal anti-VEGF therapy in patients with exsudative AMD have been published so far. We report on the outcome of patients receiving intravitreal anti-VEGF therapy for exudative AMD at the Department of Ophthalmology, University Hospital of Zurich with follow-up of 3 to 7 years. Retrospective chart review of all patients treated at our institution for exudative AMD with begin of treatment since 2006. The numbers of patients with a follow-up of 3 to 4, 4 to 5, 5 to 6, 6 to 7, and more than 7 years were 430, 277, 151, 87, and 47, respectively. Mean follow-up time was 4.9 years, and median was 4.6 years. Changes in visual acuity for these patients were - 5.0, - 7.8, - 11.7, - 12.8, and - 19.2 ETDRS letters, respectively. Whereas in patients with exudative AMD during the first two years of intravitreal anti-VEGF treatment visual acuity can at least be stabilised, after three and more years visual acuity decreases in spite of continued treatment. Georg Thieme Verlag KG Stuttgart · New York.
Unfallchirurg, Jan 25, 2008
Klinische Monatsblatter Fur Augenheilkunde, Apr 1, 2010
Background: Treatment of neovascular age-related macular degeneration (AMD) with Lucentis® shows ... more Background: Treatment of neovascular age-related macular degeneration (AMD) with Lucentis® shows a broad spectrum regarding the course of visual acuity (VA). While some patients show a good response (increase in VA), others disclose much less promising results. Patients and Methods: A retrospective data analysis of all eyes treated for neovascular AMD at the University Hospital of Zurich, Switzerland for at least 12 months was carried out. The courses of VA between the 90th (good responders, GR) and the 10th (bad responders, BR) percentiles were compared at 3, 12 and 24 months from baseline. An analysis regarding demographic data, lesion type and size as well as injection frequency and visits was done and predictive factors for GR and BR were evaluated. Results: Marked differences in the course of VA between GR (n = 30) and BR (n = 30) are already observed 3 months from baseline. In GR the gains in VA after 3, 12 and 24 were 15.7 ± 9 letters ETDRS, 25.3 ± 7 and 14.0 ± 14. BR showed a deterioration of 8.3 ± 11 letters ETDRS after 3, 22.1 ± 8 after 12 and 23.6 ± 13 after 24 months. The gender distribution was equal with a higher percentage of female patients (64 % in BR and 66 % in GR). The baseline VA was statistically significantly lower in GR (45.7 ± 10 vs. 55.4 ± 11, p < 0.05) than in BR. No other significant differences in baseline data were found, and no predictor for group membership could be identified. Conclusions: Only the course of VA in the first three months seems to be of value for an estimation of the response to treatment. In the future the response to treatment in the early phase may influence the treatment algorithm and the injection frequency.
Clinical validation of a patient-specific model of the cornea on cataract interventions
Disease characteristics. VCAN-related vitreoretinopathy, which includes Wagner syndrome and erosi... more Disease characteristics. VCAN-related vitreoretinopathy, which includes Wagner syndrome and erosive vitreoretinopathy (ERVR), is characterized by “optically empty vitreous” on slit-lamp examination and avascular vitreous strands and veils, mild or occasionally moderate to severe myopia, presenile cataract, night blindness of variable degree associated with progressive chorioretinal atrophy, retinal detachment at advanced stages of the disease, and reduced visual acuity. Systemic abnormalities are not observed. The first signs usually become apparent during early adolescence, but onset can be as early as age two years. Diagnosis/testing. The clinical diagnosis of VCAN-related vitreoretinopathy is established based on typical clinical findings and a family history consistent with autosomal dominant inheritance. VCAN (previously CSPG2) is the only gene known to be associated with Wagner syndrome and ERVR. Molecular genetic testing is available on a clinical basis. Management. Treatment...
Silicone Oil Tamponade for the Prevention of Posterior Arcuate Retinal Folds Following Pars Plana Vitrectomy for Superior Bullous Rhegmatogenous Retinal Detachment
Investigative Ophthalmology & Visual Science, 2008
Kombinationstherapie mit PDT und Avastin bei der AMD
Klinische Monatsblätter für Augenheilkunde, 2006
Langzeit-Verlauf bei Patienten mit intravitrealer Anti-VEGF Therapie für neovaskuläre AMD
Klinische Monatsblätter für Augenheilkunde, 2015
ABSTRACT Randomized controlled phase III studies have shown that intravitreal anti-VEGF therapy i... more ABSTRACT Randomized controlled phase III studies have shown that intravitreal anti-VEGF therapy is effective for exsudative age-related macular degeneration (AMD) over two years. Recently, the seven-year outcomes in ranibizumab-treated patients of the ranibizumab phase III studies have been published. Only a few other studies with such a long follow-up for intravitreal anti-VEGF therapy in patients with exsudative AMD have been published so far. We report on the outcome of patients receiving intravitreal anti-VEGF therapy for exudative AMD at the Department of Ophthalmology, University Hospital of Zurich with follow-up of 3 to 7 years. Retrospective chart review of all patients treated at our institution for exudative AMD with begin of treatment since 2006. The numbers of patients with a follow-up of 3 to 4, 4 to 5, 5 to 6, 6 to 7, and more than 7 years were 430, 277, 151, 87, and 47, respectively. Mean follow-up time was 4.9 years, and median was 4.6 years. Changes in visual acuity for these patients were - 5.0, - 7.8, - 11.7, - 12.8, and - 19.2 ETDRS letters, respectively. Whereas in patients with exudative AMD during the first two years of intravitreal anti-VEGF treatment visual acuity can at least be stabilised, after three and more years visual acuity decreases in spite of continued treatment. Georg Thieme Verlag KG Stuttgart · New York.
Computer Aided Surgery, 2003
Objective: Precise transducer calibration is an essential prerequisite for reliable surface regis... more Objective: Precise transducer calibration is an essential prerequisite for reliable surface registration based on ultrasound B-mode imaging devices. The clinical usage of a novel B-mode trans- ducer calibration technique was evaluated and its attainable calibration precision assessed. Materials and Methods: The Three Wire Method and the Cambridge Calibration Method were used as reference techniques to compare the efficiency, calibration precision and spatial requirements of the different techniques. A total of 20 calibration trials were performed using each technique and were statistically evaluated for accuracy and speed. Results: The mean error characterizing the calibration precision of the Three Wire Method was 3.2 mm, obtained in a phantom with a volume of 14 x lo6 nun' in 18.48 min. The Cambridge method resulted in a mean calibration error of 2.2 mm, but required a larger phantom with a volume of 35 x lo6 mm3 to be used for a duration of 9.30 min. The proposed method yielded an average calibration error of 1.9 mm and was performed, on average, in 2 min using a phantom with a size smaller than 1 x lo6 mm3. Conclusions: The suggested calibration method offers decreased time and space while retaining an equivalent calibration precision when compared to established reference methods.
Klinische Monatsblätter für Augenheilkunde, 2010
Hintergrund: Die Visusverläufe unter der Therapie mit Ranibizumab (Lucentis®) bei neovaskulärer a... more Hintergrund: Die Visusverläufe unter der Therapie mit Ranibizumab (Lucentis®) bei neovaskulärer altersbedingter Makuladegeneration (AMD) zeigen ein breites Spektrum. Während einige Patienten sehr gut ansprechen und eine Visusverbesserung erfahren, zeigen andere deutlich schlechtere Resultate trotz ähnlicher Therapieregimes. Patienten und Methoden: Retrospektive Analyse aller am UniversitätsSpital Zürich über mindestens 12 Monate mit Lucentis® behandelten Augen mit neovaskulärer AMD. Vergleich der Visusverläufe der 90. (good responders, GR) und 10. Percentile (bad responders, BR) nach 3, 12 und 24 Monate und Analyse der demographischen Charakteristiken, Läsionstyp und -grösse sowie Anzahl durchschnittliche Ranibizumab Injektionen und Kontrollen. Evaluation prädiktiver Faktoren für die Zugehörigkeit zu einer der beiden Gruppen. Ergebnisse: Ein deutlicher Unterschied der Visusverläufe zwischen GR (n=30) und BR (n=30) zeigt sich bereits in den ersten 3 Monaten nach Behandlungsbeginn. In GR betrug der Visusgewinn 15.7±9 Buchstaben ETDRS nach 3 Monaten, 25.3±7 nach 12 und 14.0±14 nach 24 Monaten. In BR zeigte sich ein Verlust von 8.3±11 Buchstaben ETDRS nach 3 Monaten, 22.1±8 nach 12 und 23.6±13 24 Monate. Erwartungsgemäss zeigte sich in den beiden Gruppen einen höheren Anteil an Frauen (64% in BR, 66% in GR). Einzig der Ausgangsvisus war in GR statistisch signifikant schlechter als in BR (45.7±10 vs 55.4±11 Buchstaben ETDRS, p<0.05). Weitere signifikante Unterschiede fanden sich nicht. Ausgehend von den analysierten Daten konnten keine prädiktive Faktoren für die Gruppenzugehörigkeit (BR/GR) ermittelt werden. Schlussfolgerungen: Allein der Visusverlauf innerhalb der ersten 3 Monate nach Therapiebeginn scheint Hinweise für das weitere Ansprechen der intravitrealen Ranibizumab Therapie zu liefern. Der Therapieverlauf in den ersten Monaten könnte in Zukunft das Therapieschema und die Injektionsfrequenz wesentlich beeinflussen. Abstract (English) Background: Treatment of neovascular age related macular degeneration (AMD) with Lucentis® shows a broad spectrum regarding the course of visual acuity (VA). While some patients show a good response (increase in VA), others disclose much less promising results. Patients and Methods: Retrospective data analysis of all eyes treated for neovascular AMD at the University Hospital of Zurich, Switzerland for at least 12 months. Comparison of the courses of VA between 90th (good responders, GR) and 10th (bad responders, BR) percentiles 3, 12 and 24 months from baseline. Analysis regarding demographic data, lesion type and size as well as injection frequency and visits. Evaluation of predicitive factors for GR and BR. Results: Marked difference in the course of VA between GR (n=30) and BR (n=30) is already observed 3 months from baseline. In GR the gain in VA after 3, 12 and 24 was 15.7±9 letters ETDRS, 25.3±7 and 14.0±14. BR showed a deterioration of 8.3±11 letters ETDRS after 3, 22.1±8 after 12 and 23.6±13 after 24 months. The gender distribution was equal with a higher percentage of female patients (64% in BR and 66% in GR). The baseline VA was statistically significant lower in GR (45.7±10 vs. 55.4±11, p<0.05) than in BR. No other significant differences in baseline data were found, no predictor for group membership could be identified. Conclusions: Only the course of VA in the first three months seems to be of value for an estimation of the response to treatment. In the future the response to treatment in the early phase may influence the treatment algorithm and the injection frequency.
Follicular Conjunctivitis Caused by a Mantle Cell Lymphoma
Klinische Monatsblätter für Augenheilkunde, 2004
Lymphoma of the conjunctiva as part of a systemic disease is rare. The follicular appearance of t... more Lymphoma of the conjunctiva as part of a systemic disease is rare. The follicular appearance of the lymphocyte hyperplasia may mimic the clinical picture of infectious or allergic conjunctivitis. We report on a case of marked chronic follicular conjunctivitis, finally diagnosed as mantle cell lymphoma. A 52-year old male with a history of epiphora for one year, presented with follicular conjunctivitis in both eyes, a nodal mass in the upper right eyelid and nuchal lymphadenopathy. No infectious or allergic aetiology could be found. Conjunctival biopsy revealed a mantle cell lymphoma. Magnetic resonance tomography showed a bilateral spread into the orbital cavity. Other sites of involvement were the epipharynx and the cervical, axillary and paratracheal lymph nodes. Chemotherapy with hyper-CVAD (cyclophosphamide, vincristine, doxorubicine, dexamethasone) was initiated. After 4 of 6 cycles, all clinical tumour manifestations had disappeared completely. Conjunctival lymphoma may clinically resemble follicular conjunctivitis. Conjunctival biopsy may lead to early diagnosis and initiation of therapy.
Accuracy of navigated surgery of the pelvis after surface matching with an a‐mode ultrasound probe
Journal of Orthopaedic Research, 2008
Computer‐aided surgery (CAS) allows for real‐time intraoperative feedback resulting in increased ... more Computer‐aided surgery (CAS) allows for real‐time intraoperative feedback resulting in increased accuracy, while reducing intraoperative radiation. CAS is especially useful for the treatment of certain pelvic ring fractures, which necessitate the precise placement of screws. Flouroscopy‐based CAS modules have been developed for many orthopedic applications. The integration of the isocentric flouroscope even enables navigation using intraoperatively acquired three‐dimensional (3D) data, though the scan volume and imaging quality are limited. Complicated and comprehensive pathologies in regions like the pelvis can necessitate a CT‐based navigation system because of its larger field of view. To be accurate, the patient's anatomy must be registered and matched with the virtual object (CT data). The actual precision within the region of interest depends on the area of the bone where surface matching is performed. Conventional surface matching with a solid pointer requires extensive s...
Journal of Biomechanics, 2013
Validation of a numerical method to compute arterial deformations under the insertion of an "extr... more Validation of a numerical method to compute arterial deformations under the insertion of an "extra-siff" guidewire during Endovascular Repair of Abdominal Aortic Aneurysm. Methods: We propose the validation of a previously developed simulation method. The model is calibrated using anatomical hypothesis and intraoperative observations. Simulation results are blindly evaluated against 3D imaging data acquired during the surgical procedure on 28 patients, based on the predicted position of the intraoperative guidewire. Results: Simulation was successfully conducted on the 28 patients. The mean position error given by the Modified Hausdorff Distance for the 28 cases was 3.8 ± 1.9 mm, which demonstrates very good results for most of the cases. Conclusion: The work reported here shows that numerical simulation can predict some rather large variations in the vascular geometry due to tools insertion, for a wide variety of aorto-iliac morphologies. This is a new step toward clinically applicable mechanical simulation. Significance: Validation on 3D intraoperative data on a large number of cases-Robustness on adverse anatomies.
Journal of American Association for Pediatric Ophthalmology and Strabismus, 2010
To report the long-term outcome of full-tendon vertical rectus muscle transposition combined with... more To report the long-term outcome of full-tendon vertical rectus muscle transposition combined with chemodenervation of the ipsilateral medial rectus muscle for acquired chronic sixth (abducens) nerve palsy. A retrospective study of all patients treated for severe abduction deficit with transposition plus botulinum toxin over the course of 11 years. Minimum follow-up was 12 months. Main outcome measures were the surgical result and its stability. RESULTS A total of 22 patients were included. Mean age at the time of surgery was 41.7 AE 19.1 years (range, 4.5-69). The etiologies for the palsy were head trauma (11), tumor (10), and idiopathic (1). Mean follow-up time was 44.2 AE 37.4 months (range, 12-123). The average distance deviation was 38.1 D AE 11.6 D preoperatively, 4.0 D AE 16.1 D 3 months after the operation (p 5 0.0004), and 7.9 D AE 8.8 D at 12 months (p 5 0.0003), with no subsequent change. At the final examination, on average 44.2 months after the operation, 13 patients (59%) were within 10 D of alignment, 2 (1%) were overcorrected, and 7 (32%) had vertical deviations. The majority of patients (73%) had no double vision in the primary position. No patient developed anterior segment ischemia. CONCLUSIONS Vertical rectus muscle transposition combined with intraoperative botulinum toxin injection into the ipsilateral medial rectus muscle improved alignment in patients with complete chronic sixth nerve palsy. While the effects of treatment may have diminished slightly during the first year after surgery, they remained stable thereafter. ( J AAPOS 2010;14:498-501)
International Journal of Radiation Oncology*Biology*Physics, 2012
IEEE Transactions on Biomedical Engineering, 2010
Accurate placement of lesions is crucial for the effectiveness and safety of a retinal laser phot... more Accurate placement of lesions is crucial for the effectiveness and safety of a retinal laser photocoagulation treatment. Computer assistance provides the capability for improvements to treatment accuracy and execution time. The idea is to use video frames acquired from a scanning digital ophthalmoscope (SDO) to compensate for retinal motion during laser treatment. This paper presents a method for the multimodal registration of the initial frame from an SDO retinal video sequence to a retinal composite image, which may contain a treatment plan. The retinal registration procedure comprises the following steps: 1) detection of vessel centerline points and identification of the optic disc; 2) prealignment of the video frame and the composite image based on optic disc parameters; and 3) iterative matching of the detected vessel centerline points in expanding matching regions. This registration algorithm was designed for the initialization of a real-time registration procedure that registers the subsequent video frames to the composite image. The algorithm demonstrated its capability to register various pairs of SDO video frames and composite images acquired from patients.
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Papers by Christoph Amstutz