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1.
Arch Phys Med Rehabil ; 104(12): 1987-1994, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37582475

RESUMEN

OBJECTIVE: To investigate the efficacy of the augmented reality (AR) app "Negami" as an active exploration training for the treatment of spatial neglect. Improvements of the ipsilesional attention and orientation bias (and resulting contralesional neglect) will be examined in stroke patients with spatial neglect and compared with a control group. DESIGN: Randomized controlled trial with an experimental Negami group, consisting of patients with spatial neglect, and a group of neglect patients receiving standard neglect therapy. SETTING: Three rehabilitation hospitals. PARTICIPANTS: Twenty right hemispheric stroke patients with spatial neglect (N=20). INTERVENTION: Over a period of 2 weeks, both groups received 5 training sessions per week (à 25 minutes). Neglect behavior was assessed weekly over a 5-week period, with the Negami therapy group receiving a second follow-up assessment at 1-to-2-month intervals after completion of training. MAIN OUTCOME MEASURES: Letter Cancellation, Bells Test, Copying Task, Line Bisection Task, and a self-developed "Exploration Test". RESULTS: Both groups improved significantly. While the Negami therapy group improved in 4 of 5 neglect tests used, the standard therapy group improved in only 1 of these tests. We observed significantly better improvement in the Negami group already after the first week of training. This difference was also significant after the end of the training as well as 1 week after the end of training and remained stable 1-2 months after the end of treatment. CONCLUSION: Negami can be used as an effective alternative or addition to current standard neglect therapy, and may even be superior to it.


Asunto(s)
Realidad Aumentada , Aplicaciones Móviles , Trastornos de la Percepción , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular/complicaciones , Trastornos de la Percepción/etiología , Trastornos de la Percepción/rehabilitación , Rehabilitación de Accidente Cerebrovascular/métodos
2.
PLoS One ; 17(11): e0277601, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36445903

RESUMEN

In biotechnology, cell growth is one of the most important properties for the characterization and optimization of microbial cultures. Novel live-cell imaging methods are leading to an ever better understanding of cell cultures and their development. The key to analyzing acquired data is accurate and automated cell segmentation at the single-cell level. Therefore, we present microbeSEG, a user-friendly Python-based cell segmentation tool with a graphical user interface and OMERO data management. microbeSEG utilizes a state-of-the-art deep learning-based segmentation method and can be used for instance segmentation of a wide range of cell morphologies and imaging techniques, e.g., phase contrast or fluorescence microscopy. The main focus of microbeSEG is a comprehensible, easy, efficient, and complete workflow from the creation of training data to the final application of the trained segmentation model. We demonstrate that accurate cell segmentation results can be obtained within 45 minutes of user time. Utilizing public segmentation datasets or pre-labeling further accelerates the microbeSEG workflow. This opens the door for accurate and efficient data analysis of microbial cultures.


Asunto(s)
Manejo de Datos , Aprendizaje Profundo , Programas Informáticos , Flujo de Trabajo , Análisis de Datos
3.
Radiat Oncol ; 16(1): 51, 2021 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-33726751

RESUMEN

BACKGROUND: Several radiotherapeutic approaches for patients with oligotopic malignant liver lesions unfit for surgical resection exist. The most advanced competitive techniques are high-dose-rate (HDR) brachytherapy, Cyberknife, volume-modulated-arc therapy (VMAT) and Tomotherapy. We evaluated the optimal technique by a planning study for a single ablative dose with different lesion sizes. METHODS: We compared dose distributions of HDR-brachytherapy with stereotactic ablative radiotherapy using the Cyberknife, VMAT or Tomotherapy. Tumor-control-probabilities (TCP), normal-tissue-complication-probabilities (NTCP) were determined in a theoretical framework applying a single dose of 20 Gy (demanding 95% coverage) for intrahepatic lesions of 1-5 cm in size. We evaluated therapeutic ratios by TCP (mean dose in the lesion) relative to high-dose (conformality) or low-dose liver exposition in dependency on the lesion size for each technique. In addition, we considered treatment times and accuracy (clinical target volume vs planning target volume). RESULTS: HDR-brachtherapy has the highest therapeutic ratios with respect to high-dose as well as low-dose liver exposition even for extended lesions, and the Cyberknife being suited second best. However, for lesions ≥ 3 cm diameter the therapeutic ratios of all ablative techniques are increasingly converging, and better tolerance and shorter treatment times of noninvasive external techniques become more important. On the other hand, mean tumor doses of HDR-brachytherapy of near 60 Gy are unattainable by the other techniques gaining only 22-34 Gy, and the conformality of HDR-brachytherapy is still rather good for lesions ≥ 3 cm diameter. CONCLUSIONS: HDR-brachytherapy is by far the most effective technique to treat intrahepatic lesions by a single fraction, but sparing of the surroundings declines with increasing lesion size and approaches the benchmarks of external beam radiosurgery techniques. External beam radiotherapy has the advantage to use suitable fractionation schedules.


Asunto(s)
Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/secundario , Braquiterapia , Humanos , Tolerancia a Radiación , Radiocirugia , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada , Factores de Tiempo
4.
Radiat Oncol ; 10: 91, 2015 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-25896675

RESUMEN

BACKGROUND: To compare highly sophisticated intensity-modulated radiotherapy (IMRT) delivered by either helical tomotherapy (HT), RapidArc (RA), IMRT with protons (IMPT) in patients with locally advanced cervical cancer. METHODS AND MATERIALS: Twenty cervical cancer patients were irradiated using either conventional IMRT, VMAT or HT; ten received pelvic (PEL) and ten extended field irradiation (EFRT). The dose to the planning-target volume A (PTV_A: cervix, uterus, pelvic ± para-aortic lymph nodes) was 1.8/50.4 Gy. The SIB dose for the parametrium (PTV_B), was 2.12/59.36 Gy. MRI-guided brachytherapy was administered with 5 fractions up to 25 Gy. For EBRT, the lower target constraints were 95% of the prescribed dose in 95% of the target volume. The irradiated small bowel (SB) volumes were kept as low as possible. For every patient, target parameters as well as doses to the organs at risk (SB, bladder, rectum) were evaluated intra-individually for IMRT, HT, VMAT and IMPT. RESULTS: All techniques provided excellent target volume coverage, homogeneity, conformity. With IMPT, there was a significant reduction of the mean dose (Dmean) of the SB from 30.2 ± 4.0 Gy (IMRT); 27.6 ± 5.6 Gy (HT); 34.1 ± 7.0 (RA) to 18.6 ± 5.9 Gy (IMPT) for pelvic radiation and 26.3 ± 3.2 Gy (IMRT); 24.0 ± 4.1 (HT); 25.3 ± 3.7 (RA) to 13.8 ± 2.8 Gy (IMPT) for patients with EFRT, which corresponds to a reduction of 38-52% for the Dmean (SB). Futhermore, the low dose bath (V10Gy) to the small bowel was reduced by 50% with IMPT in comparison to all photon techniques. Furthermore, Dmean to the bladder and rectum was decresed by 7-9 Gy with IMPT in patents with pelvic radiation and EFRT. CONCLUSION: All modern techniques (were proved to be dosimetrically adequate regarding coverage, conformity and homogeneity of the target. Protons offered the best sparing of small bowel and rectum and therefore could contribute to a significant reduction of acute and late toxicity in cervical cancer treatment.


Asunto(s)
Adenocarcinoma/radioterapia , Carcinoma de Células Escamosas/radioterapia , Fotones/uso terapéutico , Terapia de Protones/métodos , Radioterapia de Intensidad Modulada/métodos , Neoplasias del Cuello Uterino/radioterapia , Adenocarcinoma/patología , Adulto , Anciano , Carcinoma de Células Escamosas/patología , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Órganos en Riesgo , Pelvis/efectos de la radiación , Pronóstico , Dosificación Radioterapéutica , Recto/efectos de la radiación , Vejiga Urinaria/efectos de la radiación , Neoplasias del Cuello Uterino/patología
5.
Strahlenther Onkol ; 190(5): 453-8, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24595415

RESUMEN

PURPOSE: The aim of this chart review of adult patients treated for acute lymphoblastic leukemia (ALL) with total body irradiation (TBI) was to evaluate early and late toxicity and long-term outcome. PATIENTS AND METHODS: A total of 110 adult patients (34 ± 12 years) with ALL underwent TBI (6 fractions of 2 Gy for a total of 12 Gy) as a part of the treatment regimen before transplantation. Treatment-related toxicity, mortality, and hematologic outcome are reported. RESULTS: Mean follow-up was 70 months. The 2- and 5-year leukemia-free survival rates were 78 and 72%, respectively. In all, 29% (32/110) patients suffered from medullary recurrence after a median time of 7 months. Gender was the only statistically significant prognostic factor in terms of overall survival in favor of female patients. Treatment-related mortality and overall survival after 2 and 5 years were 16 and 22%, and 60 and 52.7%, respectively. The most frequent late reaction wascGVHD of the skin (n = 33, 30%). In addition, 15.5% (17/110 patients) suffered pulmonary symptoms, and 6 patients developed lung fibrosis. Eyes were frequently affected by the radiation (31/110 = 28%); 12 of 110 patients (11%) presented with symptoms from osteoporosis, 5 of 110 patients (4.5%) developed hypothyreosis and 2 patients diabetes mellitus. Of the male patients, 11% reported erectile dysfunction or loss of libido, while 2 of 36 women reported menopausal syndrome at the mean time of 28 months after treatment with requirement for substitution. No women became pregnant after treatment. No acute or late cardiac toxicities were documented in our patients. No secondary malignancies were documented. CONCLUSION: Although hematologic outcome was in the upper range of that reported in the literature, treatment-related mortality (TRM) and medullary recurrences remain a challenge. Sophisticated radiation techniques allow for decreasing toxicity to certain organs and/or dose escalation to the bone marrow in highly selected patients in order to improve therapeutic breadth.


Asunto(s)
Leucemia-Linfoma Linfoblástico de Células Precursoras/radioterapia , Irradiación Corporal Total , Adulto , Purgación de la Médula Ósea , Terapia Combinada , Supervivencia sin Enfermedad , Femenino , Enfermedad Injerto contra Huésped/etiología , Trasplante de Células Madre Hematopoyéticas , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidad , Traumatismos por Radiación/etiología , Traumatismos por Radiación/mortalidad , Estudios Retrospectivos
6.
Strahlenther Onkol ; 190(6): 538-45, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24589918

RESUMEN

BACKGROUND AND PURPOSE: To compare MRI-guided brachytherapy (BT) and two different dose prescriptions for robotic radiosurgery (RRS) in locally advanced cervical cancer. METHODS AND MATERIALS: Eleven patients with FIGO stage IIB-IIIB cervical cancer underwent RRS instead of BT for various reasons. A total dose of 30 Gy was administered in five fractions. The maximum dose was chosen such that the prescribed dose was 70 % of the maximum dose (RRS70). To simulate BT more closely, additional plan calculations were carried out for a higher maximum dose with the same enclosing dose of 30 Gy being now 25 % of the maximum dose (RRS25). BT plans were calculated for the same patients (BTRRS). Finally, the resulting three sets of treatment plans were compared with 38 other patients treated with MRI-guided BT and the same dose prescription (BTref). Plan comparisons were performed based on DVH parameters with regard to target coverage (V100), conformation number (CN), and sparing of the organs at risk (OARs). RESULTS: The best coverage of V100 = 100 ± 0 % was obtained with RRS25, followed by RRS70 with 97.1 ± 2.7 %, BTref with 90.9 ± 8.9 %, and the intraindividual BTRRS with 80.6 ± 6.4 %. The sparing of OARs was associated with D0.1 cc, D2 cc, and D5 cc to the rectum, sigmoid, and bladder walls. OAR doses were compliant with the GEC-ESTRO guidelines and comparable among RRS70, RRS25, BTRRS, and BTref. By contrast, RRS25 could not fulfill these guidelines, exceeding considerably the tolerable dose constraints for the walls of the critical OARs. CONCLUSION: Despite of the excellent coverage and higher maximum dose, the unacceptably high exposure to the OARs disqualified RRS25 as an alternative for BT in cervical cancer patients. By contrast, RRS70 offered the best protection for the OARs, comparable to BT, and even better target coverage and conformity than BT.


Asunto(s)
Braquiterapia/métodos , Imagen por Resonancia Magnética Intervencional/métodos , Radiocirugia/métodos , Robótica/métodos , Neoplasias del Cuello Uterino/cirugía , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Neoplasias del Cuello Uterino/patología
7.
Int J Radiat Oncol Biol Phys ; 87(5): 897-903, 2013 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-24119834

RESUMEN

PURPOSE: To evaluate intensity modulated proton therapy (IMPT) in patients with cervical cancer in terms of coverage, conformity, and dose-volume histogram (DVH) parameters correlated with recommendations from magnetic resonance imaging (MRI)-guided brachytherapy. METHODS AND MATERIALS: Eleven patients with histologically proven cervical cancer underwent primary chemoradiation for the pelvic lymph nodes, the uterus, the cervix, and the parametric region, with a symmetric margin of 1 cm. The prescription was for 50.4 Gy, with 1.8 Gy per fraction. The prescribed dose to the parametria was 2.12 Gy up to 59.36 Gy in 28 fractions as a simultaneous boost. For several reasons, the patients were unable to undergo brachytherapy. As an alternative, IMPT was planned with 5 fractions of 6 Gy to the cervix, including the macroscopic tumor with an MRI-guided target definition, with an isotropic margin of 5 mm for planning target volume (PTV) definition. Groupe-Europeen de Curietherapie and European society for Radiotherapy and Oncology (GEC-ESTRO) criteria were used for DVH evaluation. Reference comparison plans were optimized for volumetric modulated rapid arc (VMAT) therapy with the RapidArc (RA). RESULTS: The dose to the high-risk volume was calculated with α/ß = 10 with 89.6 Gy. For IMPT, the clinical target volume showed a mean dose of 38.2 ± 5.0 Gy (35.0 ±1.8 Gy for RA). The D98% was 31.9 ± 2.6 Gy (RA: 30.8 ± 1.0 Gy). With regard to the organs at risk, the 2Gy Equivalent Dose (EQD2) (α/ß = 3) to 2 cm(3) of the rectal wall, sigmoid wall, and bladder wall was 62.2 ± 6.4 Gy, 57.8 ± 6.1 Gy, and 80.6 ± 8.7 Gy (for RA: 75.3 ± 6.1 Gy, 66.9 ± 6.9 Gy, and 89.0 ± 7.2 Gy, respectively). For the IMPT boost plans in combination with external beam radiation therapy, all DVH parameters correlated with <5% risk for grades 2 to 4 late gastrointestinal and genitourinary toxicity. CONCLUSION: In patients who are not eligible for brachytherapy, IMPT as a boost technique additionally to external beam radiation therapy provides good target coverage and conformity and superior DVH parameters, compared with recommendations to MRI-guided brachytherapy. For selected patients, IMPT might be a valid alternative to brachytherapy and also superior to reference VMAT plans.


Asunto(s)
Braquiterapia , Terapia de Protones/métodos , Radioterapia Guiada por Imagen/métodos , Radioterapia de Intensidad Modulada/métodos , Neoplasias del Cuello Uterino/radioterapia , Adenocarcinoma/patología , Adenocarcinoma/radioterapia , Adulto , Anciano , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/radioterapia , Colon Sigmoide/efectos de la radiación , Femenino , Humanos , Imagen por Resonancia Magnética Intervencional/métodos , Persona de Mediana Edad , Órganos en Riesgo/efectos de la radiación , Dosificación Radioterapéutica , Recto/efectos de la radiación , Vejiga Urinaria/efectos de la radiación , Neoplasias del Cuello Uterino/patología
8.
Radiat Oncol ; 8: 109, 2013 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-23638755

RESUMEN

PURPOSE: To evaluate the technique, dosimetry, dose-volume-histograms (DVHs) and acute toxicity for CyberKnife® boost irradiation instead of intra-cervical brachytherapy in patients with cervical cancer. METHODS AND MATERIALS: Eleven who were not suitable for brachytherapy with FIGO stage IIB-IIIB cervical cancer underwent primary chemoradiation. After fiducial implantation, T2 contrast-enhanced planning MRI and CT scans at 2-mm slice thickness were collected in the treatment position. The clinical target volume was defined as cervix + macroscopic residual tumour on MRI. Five fractions of 6 Gy each were prescribed to the target volume with a covering single dose 6 Gy. DVH parameters were evaluated for the target and organs at risk. Acute toxicity was documented once a week. RESULTS: DmeanPTV ranged from 33.6-40 Gy, median 36.7 Gy with a coverage of the PTV calculated to 100% of the prescribed dose ranging from 93.0-99.3% (median 97.7%). For the PTV the median CN was 0.78 (range, 0.66 to 0.87) and the median CI was 1.28 (range 1.15 to 1.52). Gastrointestinal (GI) and genitourinary (GU) toxicity was mild. There was no grade 3 or higher GI and GU toxicity. After 6 months of follow up, there were no local recurrences. For the complete treatment, a median EQD2 to 1 cc and 2 cc of the bladder wall was 98.8 Gy and 87.1 Gy, respectively. Median EQD2 to 1 cc and 2 cc of the rectal wall was 72.3 Gy and 64 Gy, respectively, correlating with a risk < 10% for Grade 2-4 late toxicity. CONCLUSIONS: CyberKnife robotic radiosurgery in patients with cervical cancer provides excellent target coverage with steep dose gradients toward normal tissues and safe DVH parameters for bladder, rectum and sigmoid. Acute toxicity was mild. Longer follow-up is needed to evaluate the oncological equality.


Asunto(s)
Braquiterapia/métodos , Radiocirugia/métodos , Procedimientos Quirúrgicos Robotizados/métodos , Neoplasias del Cuello Uterino/cirugía , Adulto , Anciano , Femenino , Marcadores Fiduciales , Humanos , Persona de Mediana Edad , Planificación de la Radioterapia Asistida por Computador , Robótica/métodos
9.
Radiat Oncol ; 8: 92, 2013 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-23587349

RESUMEN

BACKGROUND: Establishing Total Body Irradiation (TBI) using Helical Tomotherapy (HT) to gain better control over dose distribution and homogeneity and to individually spare organs at risk. Because of their limited body length the technique seems especially eligible in juvenile patients. PATIENTS AND METHODS: The cohort consisted of 10 patients, 6 female and 4 male, aged 4 - 22 y with acute lymphoblastic- (ALL) or acute myeloic leukemia (AML). All patients presented with high risk disease features. Body length in treatment position ranged from 110-180 cm. Two Gy single dose was applied BID to a total dose of 12 Gy. Dose volume constraint for the PTV was 95% dose coverage for 95% of the volume. The lungs were spared to a mean dose of [less than or equal to] 10 Gy. Patients were positioned in a vac-loc bag in supine position with a 3-point head mask. RESULTS: Average D95 to the PTV was 11.7 Gy corresponding to a mean coverage of the PTV of 97.5%. Dmean for the lungs was 9.14 Gy. Grade 3-4 side effects were not observed. CONCLUSIONS: TBI using HT is feasible and well tolerated. A benefit could be demonstrated with regard to dose distribution and homogeneity and the selective dose-reduction to organs at risk.


Asunto(s)
Trasplante de Células Madre/métodos , Irradiación Corporal Total/métodos , Adolescente , Niño , Preescolar , Femenino , Humanos , Leucemia Mieloide Aguda/terapia , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Dosificación Radioterapéutica , Radioterapia de Intensidad Modulada , Adulto Joven
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