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1.
Klin Monbl Augenheilkd ; 238(5): 617-639, 2021 May.
Artigo em Alemão | MEDLINE | ID: mdl-33592637

RESUMO

Echography (also ultrasound) is a clinical, non-invasive imaging module that is used for the measurement of the axial length of the eye and for the investigation of pathologic entities of the chamber angle, the iris and the ciliary body. Furthermore, its role in the management of vitreoretinal pathologies and the differentiation of intraocular tumors is indisputable. Echography remains the first-choice imaging tool in case of insufficient visualization of the posterior segment due to opacity or obstruction of the optical media of the eye. In addition, it can contribute to a more precise diagnostic characterization of lesions in all eye segments. Patients with corneal opacities, abnormalities of the iris, the chamber angle and the ciliary body, as well as patients with dense cataract, vitreous hemorrhage or inflammatory opacities can be properly diagnosed via ultrasound and be treated accordingly.


Assuntos
Segmento Anterior do Olho , Opacidade da Córnea , Segmento Anterior do Olho/diagnóstico por imagem , Corpo Ciliar/diagnóstico por imagem , Humanos , Iris , Ultrassonografia
2.
Phys Med ; 121: 103358, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38643558

RESUMO

PURPOSE: To review required margins in ocular proton therapy (OPT) based on an uncertainty estimation and to compare them with widely used values. Further, uncertainties when using registered funduscopy images in the 3D model is investigated. METHODS: An uncertainty budget in planning and delivery was defined to determine required aperture and range margins. Setup uncertainties were considered for a cohort of treated patients and tested in a worst-case estimation. Other uncertainties were based on a best-guess and knowledge of institutional specifics, e.g. range reproducibility. Margins for funduscopy registration were defined resulting from scaling, rotation and translation of the image. Image formation for a wide-field fundus camera was reviewed and compared to the projection employed in treatment planning systems. RESULTS: Values for aperture and range with margins of 2.5 mm as reported in literature could be determined. Aperture margins appear appropriate for setup uncertainties below 0.5 mm, but depend on lateral penumbra. Range margins depend on depth and associated density uncertainty in tissue. Registration of funduscopy images may require margins of >2 mm, increasing towards the equator. Difference in the projection may lead to discrepancies of several mm. CONCLUSIONS: The commonly used 2.5 mm aperture margin was validated as an appropriate choice, while range margins could be reduced for lower ranges. Margins may however not include uncertainties in contouring and possible microscopic spread. If a target base is contoured on registered funduscopy images care must be taken as they are subject to larger uncertainties. Multimodal imaging approach in OPT remains advisable.


Assuntos
Terapia com Prótons , Planejamento da Radioterapia Assistida por Computador , Incerteza , Humanos , Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias Oculares/radioterapia , Neoplasias Oculares/diagnóstico por imagem
3.
Ophthalmologie ; 120(9): 932-939, 2023 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-37052707

RESUMO

BACKGROUND: The health sector is facing new challenges due to the impact of climate change on health. At the same time, it significantly contributes to our society's climate footprint. Hospitals producing considerable amounts of waste are an important aspect of this burden. The aim of this work was to quantify the amount of waste produced by eye surgery and, as an optimization measure, to evaluate the effect of glass separation from residual waste. MATERIAL AND METHODS: Over a 2-week period, the waste generated by eye operations in the surgical theater of our university hospital was measured. Another 2­week long measurement was conducted after the initiation of glass separation from general waste. The data obtained allowed a comparison of the two periods, the type of waste (residual and recyclable) as well as the type of operation (intraocular, extraocular). Considering regional waste disposal costs, an economic comparison was also performed. RESULTS: In the first measurement period (196 operations), a total of 549.6 kg of waste was generated, 87% (478.3 kg) of which was residual waste, corresponding to 14.3 tons of total waste annually. Intraocular procedures generated on average 80% more waste than extraocular procedures: 18.1 ± 3.9 kg and 11.4 ± 4.0 kg, respectively, per day and theater. Separation of glass from residual waste reduced its quantity by 7.2% in the second measurement period (197 procedures). As the disposal of glass is free of charge in the city of Essen, this resulted in a small economic advantage (extrapolated to 112 € per year). CONCLUSION: The amount of waste generated by ophthalmic surgery is substantial, with a predominant proportion of non-recyclable residual waste. Intraocular operations are the cause of the majority of the waste produced. Simple measures, such as disposing of glass separately, are helpful and inexpensive to reduce the quantity of residual waste.


Assuntos
Eliminação de Resíduos , Humanos , Eliminação de Resíduos/métodos , Hospitais , Cidades
4.
Med Phys ; 50(1): 365-379, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36195575

RESUMO

BACKGROUND: Until today, the majority of ocular proton treatments worldwide were planned with the EYEPLAN treatment planning system (TPS). Recently, the commercial, computed tomography (CT)-based TPS for ocular proton therapy RayOcular was released, which follows the general concepts of model-based treatment planning approach in conjunction with a pencil-beam-type dose algorithm (PBA). PURPOSE: To validate RayOcular with respect to two main features: accurate geometrical representation of the eye model and accuracy of its dose calculation algorithm in combination with an Ion Beam Applications (IBA) eye treatment delivery system. METHODS: Different 3D-printed eye-ball-phantoms were fabricated to test the geometrical representation of the corresponding CT-based model, both in orthogonal 2D images for X-ray image overlay and in fundus view overlaid with a funduscopy. For the latter, the phantom was equipped with a lens matching refraction of the human eye. Funduscopy was acquired in a Zeiss Claus 500 camera. Tantalum clips and fiducials attached to the phantoms were localized in the TPS model, and residual deviations to the actual position in X-ray images for various orientations of the phantom were determined, after the nominal eye orientation was corrected in RayOcular to obtain a best overall fit. In the fundus view, deviations between known and displayed distances were measured. Dose calculation accuracy of the PBA on a 0.2 mm grid was investigated by comparing between measured lateral and depth-dose profiles in water for various combinations of range, modulation, and field-size. Ultimately, the modeling of dose distributions behind wedges was tested. A 1D gamma-test was applied, and the lateral and distal penumbra were further compared. RESULTS: Average residuals between model clips and visible clips/fiducials in orthogonal X-ray images were within 0.3 mm, including different orientations of the phantom. The differences between measured distances on the registered funduscopy image in the RayOcular fundus view and the known ground-truth were within 1 mm up to 10.5 mm distance from the posterior pole. No clear benefit projection of either polar mode or camera mode could be identified, the latter mimicking camera properties. Measured dose distributions were reproduced with gamma-test pass-rates of >95% with 2%/0.3 mm for depth and lateral profiles in the middle of spread-out Bragg-peaks. Distal falloff and lateral penumbra were within 0.2 mm for fields without a wedge. For shallow depths, the agreement was worse, reaching pass-rates down to 80% with 5%/0.3 mm when comparing lateral profiles in air. This is caused by low-energy protons from a scatter source in the IBA system not modeled by RayOcular. Dose distributions modified by wedges were reproduced, matching the wedge-induced broadening of the lateral penumbra to within 0.4 mm for the investigated cases and showing the excess dose within the field due to wedge scatter. CONCLUSION: RayOcular was validated for its use with an IBA single scattering delivery nozzle. Geometric modeling of the eye and representation of 2D projections fulfill clinical requirements. The PBA dose calculation reproduces measured distributions and allows explicit handling of wedges, overcoming approximations of simpler dose calculation algorithms used in other systems.


Assuntos
Terapia com Prótons , Humanos , Terapia com Prótons/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Dosagem Radioterapêutica , Prótons , Algoritmos , Imagens de Fantasmas , Método de Monte Carlo
5.
Cancers (Basel) ; 14(19)2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36230660

RESUMO

The main objective of this prospective observational study was the characterization of the feasibility and early outcome of image-guided (IG) volumetric modulated arc (VMAT) radiosurgery (SRS) followed by resection for patients with large intraocular melanoma. Our study included consecutive patients with unfavorable-risk melanoma, enrolled in an ophthalmic oncology center. IG-VMAT-SRS was applied by high-resolution 4D image guidance and monitoring. Current stereotactic technique parameters were evaluated for comparison. Side effects and eye function, based on a 5-point CTC assessment score, were quantified. In patients with tumors located more than 0.7-1 mm apart from the optic nerve, partial to complete volume-sparing of the optic nerve head could be achieved. In 95.5% of this subgroup, the vitality of the optic nerve and vision could be preserved by the multimodality-treatment approach (mean follow-up: 18 months (7.5-36 months)). The advanced technology of stereotactic radiotherapy demonstrated the achievability of steep dose gradients around the high-dose volume, with 4D-IG-VMAT dose application. These results enforce IG-VMAT-SRS followed by resection as one of the major therapeutic options for patients with large intraocular melanoma. The combination of 4D-IG high-precision SRS and resection provides an effective treatment for large intraocular melanoma, with few side effects, and enables an eye bulb and even vision preserving modus operandi.

7.
PLoS One ; 7(4): e34891, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22514688

RESUMO

BACKGROUND/OBJECTIVE: Parkinson's disease (PD) and the atypical parkinsonian syndromes multiple system atrophy (MSA), progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS) are movement disorders associated with degeneration of the central nervous system. Degeneration of the retina has not been systematically compared in these diseases. METHODS: This cross-sectional study used spectral-domain optical coherence tomography with manual segmentation to measure the peripapillar nerve fiber layer, the macular thickness, and the thickness of all retinal layers in foveal scans of 40 patients with PD, 19 with MSA, 10 with CBS, 15 with PSP, and 35 age- and sex-matched controls. RESULTS: The mean paramacular thickness and volume were reduced in PSP while the mean RNFL did not differ significantly between groups. In PSP patients, the complex of retinal ganglion cell- and inner plexiform layer and the outer nuclear layer was reduced. In PD, the inner nuclear layer was thicker than in controls, MSA and PSP. Using the ratio between the outer nuclear layer and the outer plexiform layer with a cut-off at 3.1 and the additional constraint that the inner nuclear layer be under 46 µm, we were able to differentiate PSP from PD in our patient sample with a sensitivity of 96% and a specificity of 70%. CONCLUSION: Different parkinsonian syndromes are associated with distinct changes in retinal morphology. These findings may serve to facilitate the differential diagnosis of parkinsonian syndromes and give insight into the degenerative processes of patients with atypical parkinsonian syndromes.


Assuntos
Transtornos Parkinsonianos/patologia , Tomografia de Coerência Óptica/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Retina/patologia
8.
Acta Ophthalmol ; 87(8): 866-70, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18983619

RESUMO

PURPOSE: In this retrospective case series, we studied the effect of 'heavy' silicone oil on persisting macular holes. Patients with macular holes that failed to close after conventional macular hole surgery were retreated with the longterm internal tamponade Densiron-68. METHODS: Twelve patients with primary macular holes that persisted after pars plana vitrectomy, peeling of the internal limiting membrane and internal gas tamponade with SF6 (sulphur hexafluoride) were retreated with heavy silicone oil, Densiron-68, in the University Eye Hospital, Cologne. After 1.5-4 months the Densiron-68 was removed. Best corrected visual acuity (VA), slit-lamp examination, binocular fundus examination and optical coherence tomography (OCT) were used for evaluation pre- and postoperatively. The follow-up period was 3-7 months. RESULTS: Preoperatively, all patients displayed full-thickness macular holes, with a mean size of 502.25 microm (+/- 129.39 microm). Postoperatively, 11 of 12 macular holes were closed. One patient experienced a reopening of the macular hole. Mean VA was 20/250 (1.07 +/- 0.22 logMAR) prior to treatment with Densiron-68 and 20/160 (0.84 +/- 0.24 logMAR) postoperatively. Visual acuity increased from baseline in nine patients and decreased in one. CONCLUSIONS: Retreatment of persisting macular holes with the heavy, longterm tamponade Densiron-68 resulted in anatomical closure of the hole in 11 of 12 cases. This result was accompanied by a functional improvement in VA in nine of 12 patients.


Assuntos
Perfurações Retinianas/tratamento farmacológico , Óleos de Silicone/uso terapêutico , Idoso , Câmara Anterior , Catarata/etiologia , Feminino , Seguimentos , Humanos , Pressão Intraocular/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Perfurações Retinianas/diagnóstico , Perfurações Retinianas/fisiopatologia , Perfurações Retinianas/cirurgia , Retratamento , Estudos Retrospectivos , Supuração/etiologia , Tomografia de Coerência Óptica , Falha de Tratamento , Resultado do Tratamento , Acuidade Visual
9.
J Cataract Refract Surg ; 35(12): 2136-43, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19969220

RESUMO

PURPOSE: To evaluate a new diffractive multifocal intraocular lens (IOL) as an additional (add-on) IOL for sulcus-based implantation. SETTING: Augenklinik am Neumarkt, Köln, Germany. METHODS: In this prospective study, cataract patients had phacoemulsification and IOL implantation. After phacoemulsification, an aspheric silicone monofocal IOL (MS 612 ASP-Y) with a power range of +4.00 to +27.00 diopters [D]) was implanted in the capsular bag. This was followed by sulcus placement of an add-on multifocal IOL (MS 714 PB) with a +3.50 D diffractive element for near but zero refractive power for distance. RESULTS: The study included 56 eyes of 30 patients. Three months postoperatively, the mean monocular uncorrected distance visual acuity was 0.10 logMAR +/- 0.11 (SD) (median 1.00 decimal; 20/20 Snellen), with a remaining mean postoperative spherical equivalent of 0.01 +/- 0.51 D. The mean uncorrected intermediate visual acuity was 0.20 +/- 0.15 logMAR (median 0.63 decimal; 20/30 Snellen) with a luminance of 500 lux at 1 m. The mean uncorrected near visual acuity (Early Treatment Diabetic Retinopathy chart) was 0.16 +/- 0.13 logMAR (median 0.80 decimal; Jaeger 2). No major complications (eg, iris chafing, iris capture, lens epithelial cell ingrowth, glaucoma) were associated with the add-on IOL in the sulcus. CONCLUSIONS: Combined implantation of an add-on diffractive sulcus IOL and a monofocal capsular bag IOL was safe and effective in improving far and near visual acuity in cataract surgery. Preliminary visual acuity results were similar to those in eyes with a single 1-piece diffractive multifocal IOL.


Assuntos
Implante de Lente Intraocular/métodos , Lentes Intraoculares , Facoemulsificação , Idoso , Feminino , Humanos , Cápsula do Cristalino/cirurgia , Masculino , Estudos Prospectivos , Pseudofacia/fisiopatologia , Acuidade Visual/fisiologia
10.
Graefes Arch Clin Exp Ophthalmol ; 242(8): 638-47, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15300442

RESUMO

PURPOSE: To report the practicability and efficacy of autologous iris pigment epithelium (IPE) translocation in exudative age-related macular degeneration (ARMD) over 1 year. METHODS: The consecutive interventional case series included 56 patients with exudative ARMD. During vitrectomy the submacular neovascular membrane (CNV) was removed and IPE cells, harvested from a peripheral iridectomy, were injected into the submacular space. Included were patients with subfoveal occult CNV (11 eyes), classic CNV (10 eyes), mixed CNV (17 eyes), CNV with a pigment epithelial detachment (13 eyes) or CNV with a hemorrhage (5 eyes). Outcome measures were visual acuity, foveal fixation, size of CNV and rate of recurrence based on fluorescence angiographic imaging. RESULTS: All patients underwent successful surgical removal of the CNV with consecutive subretinal IPE injection. Visual acuity was better than 20/100 in 19 patients preoperatively and in 18 patients postoperatively. A visual acuity of 20/100 or less was found in 37 patients preoperatively and in 38 patients postoperatively. Mean preoperative visual acuity (1.0+/-0.3 logMAR units) did not change significantly after 1 year (1.0+/-0.3 logMAR units). Ten eyes (18%) developed a recurrence. Fixation within the surgically denuded area could be demonstrated in 25 eyes (45%). CONCLUSIONS: Autologous IPE translocation for ARMD over one year can preserve foveal function on a low level, but cannot improve visual acuity. IPE translocation is technically feasible with a low rate of complications. Continued research seems justified to improve functional outcome.


Assuntos
Iris/transplante , Degeneração Macular/cirurgia , Epitélio Pigmentado Ocular/transplante , Transplante Heterotópico , Idoso , Feminino , Angiofluoresceinografia , Seguimentos , Fóvea Central/fisiopatologia , Humanos , Estudos Longitudinais , Degeneração Macular/diagnóstico , Degeneração Macular/fisiopatologia , Masculino , Projetos Piloto , Transplante Autólogo , Resultado do Tratamento , Acuidade Visual
11.
Graefes Arch Clin Exp Ophthalmol ; 241(10): 860-70, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14605902

RESUMO

PURPOSE: To correlate the histopathological diagnoses established by diagnostic vitrectomy and chorioretinal biopsy in patients with clinically suspected primary intraocular lymphoma (PIOL) or chronic idiopathic uveitis, and the clinical follow-up data. METHODS: Eighty-four consecutive pars plana vitrectomy (PPV) specimens, three chorioretinal biopsies and two enucleated eyes taken from 80 patients were evaluated. All PPV specimens were unfixed; these were centrifuged, the "cytospins" being stained conventionally (May-Grünwald-Giemsa) and using immunocytology (CD79a, CD3, CD68, immunoglobulin (Ig) light chains). An extended immunohistochemical panel, as well as polymerase chain reaction (PCR) for rearrangements of the Ig heavy chain gene (IgH-PCR), were used to investigate the chorioretinal biopsies and the enucleated eyes. Diagnoses, made on the basis of morphology and immunophenotype, included "reactive cellular infiltrate", "malignant lymphoma", "suspicious of neoplastic disease", and "insufficient for diagnosis". The corresponding clinical data were collected and compared with the diagnosis. RESULTS: The 80 patients consisted of 46 women and 34 men. The patients' age range varied from 21 to 100 years (mean age 62 years). Sixty-two (74%) of the 84 vitrectomy specimens were diagnosed as "reactive cellular infiltrate", 12 (14%) as definite "malignant lymphoma", 5 (6%) as "suspicious of neoplastic disease" and 5 (6%) specimens were considered "insufficient for diagnosis". An additional chorioretinal biopsy enabled an unequivocal diagnosis of PIOL to be reached in 3 patients. All PIOL were diffuse large cell B-cell lymphoma (DLBCL), with the immunophenotype CD79+, CD20+, BCL-2+, BCL-6+, MUM1+ and monotypical expression for IgM+. A monoclonal IgH-PCR amplification product was obtained in four vitrectomy specimens, two chorioretinal biopsies and one of the enucleated eyes. Comparison of the diagnoses with long-term follow-up clinical data resulted in concordance in 77 (96%) cases and discrepancies ("false-negative" diagnoses) in 3 patients (4%). The patients diagnosed with lymphoma were treated with either radiotherapy, chemotherapy or both. At final follow-up (mean 35 months), 5 patients (6%) had developed cerebral lymphomatous manifestation, and 7 (9%) had succumbed to their disease. CONCLUSION: The diagnosis of PIOL is often extremely difficult, requiring sufficient rapidly transported good-quality material, and experienced interpretation. Although cytological examination of vitreal aspirates remains the gold standard in diagnosis, examination of chorioretinal biopsies increase the reliability of diagnosing or excluding a PIOL that involves the retina or choroid. Most PIOL are DLBCL with an immunophenotype suggesting a cellular origin from germinal centre cells.


Assuntos
Neoplasias da Coroide/diagnóstico , Linfoma de Células B/diagnóstico , Linfoma Difuso de Grandes Células B/diagnóstico , Neoplasias da Retina/diagnóstico , Corpo Vítreo/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Biópsia , Neoplasias da Coroide/tratamento farmacológico , Neoplasias da Coroide/radioterapia , Terapia Combinada , Diagnóstico Diferencial , Feminino , Rearranjo Gênico de Cadeia Pesada de Linfócito B/genética , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/radioterapia , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/radioterapia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Neoplasias da Retina/tratamento farmacológico , Neoplasias da Retina/radioterapia , Estudos Retrospectivos , Uveíte/diagnóstico , Vitrectomia
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