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1.
Radiother Oncol ; 173: 102-108, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35667574

RESUMO

INTRODUCTION: The aim was to evaluate and compare the dosimetric effect and robustness towards day-to-day anatomical and setup variations in the delivered dose for photon and proton treatments of sinonasal cancer (SNC) patients. MATERIALS AND METHODS: Photon (VMAT) and proton (IMPT) plans were optimized retrospectively for 24 SNC patients. Synthetic CTs (synCT) were obtained by deforming the planning CT (pCT) to the anatomy of every daily cone-beam CT. Both VMAT and IMPT plans were recalculated on the synCTs. The recalculated daily dose was accumulated over the whole treatment on the pCT. Target coverage and dose to organs and risk (OARs) were evaluated for all patients for the nominal, daily and accumulated dose distribution. RESULTS: In general, dose to OARs farther away from the target, including brain, chiasm and contralateral optic nerve, was lower for proton plans than photon plans. Whereas, OARs in proximity of the target received a lower dose for photon plans. For proton plans, the target coverage (volume of CTV receiving 95% of prescribed dose), V95%, fell below 99% for 9/24 patients in one or more fractions. For photon plans, 4/24 patients had one or more fractions where V95% fell below 99%. For accumulated doses, V95% was below 99% only in two cases, but above 98% for all patients. CONCLUSION: Photon and proton treatment have different strengths regarding OAR sparing. The robustness was high for both treatment modalities. Patient selection for either proton or photon radiation therapy of SNC patients should be based on a case-by-case comparison.


Assuntos
Neoplasias , Terapia com Prótons , Radioterapia de Intensidade Modulada , Humanos , Órgãos em Risco , Prótons , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Estudos Retrospectivos
2.
Clin Transl Radiat Oncol ; 27: 36-43, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33490653

RESUMO

INTRODUCTION: The aim was to characterise patterns and predictability of aeration changes in the ipsilateral maxillary sinus during intensity-modulated radiotherapy (IMRT) for sinonasal cancer (SNC), and in a sample evaluate the dosimetric effects of aeration changes for both photon and proton therapy. MATERIALS AND METHODS: The study included patients treated with IMRT for SNC in a single institution in 2009-2017. The volume of air in the ipsilateral maxillary sinus was recorded in 1578 daily cone beam computer tomography (CBCT) from 53 patients. Patterns of changing air volumes were categorised as 'stable', increasing', 'decreasing', or 'erratic'. For the prediction analysis, categorisation was performed based both on the entire treatment course and the first five fractions (F1-5). Photon and proton therapy plans were generated for four patients, the one from each category with the largest aeration variation. Synthetic CT images were generated for each CBCT and all plans were recalculated on the daily synthetic CTs. RESULTS: The absolute volume of air varied considerably during the treatment course, ranging from 0 to 25.9 cm3. Changes within a single participant varied in the range of 0-18.7 cm3. In the categorisation of patterns, most patients had increasing aeration of the sinus. Generally, patterns of aeration could not be predicted from F1-5. Patients categorised as increasing in F1-5 had the best prediction, with 78% predicted correctly as increasing for the entire treatment course. The numeric correlation coefficients for target coverage and air volume were low for 3/4 scenarios (photons 0.03-0.23, protons 0.26-0.48). No straightforward correlation between the dosimetric effect and the volume changes could be detected in the sample test of four patients for neither photon nor proton therapy. CONCLUSION: The variation of aeration was large and unpredictable. No clear dosimetric consequences of the aeration variation were evident for neither IMRT nor proton therapy for the patients investigated.

3.
Clin Transl Radiat Oncol ; 25: 52-60, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33024844

RESUMO

PURPOSE: The aim of the study was to evaluate neurocognitive late effects, structural alterations and associations between cognitive impairment and radiation doses as well as cerebral tissue damage after radiotherapy for sinonasal cancer. Furthermore, the aim was to report quality of life (QoL) and self-reported cognitive capacity. MATERIALS AND METHODS: Recurrence-free patients previously treated with intensity-modulated radiotherapy with a curative intent were eligible for the study. Study examinations comprised comprehensive neurocognitive testing, MRI of the brain, and self-reported outcomes. RESULTS: A total of 27 patients were included. Median age was 67 years (range 47-83). The majority of test outcomes were below normative values in any degree, and 37% of the participants had clinically significant neurocognitive impairment when compared with normative data. Correlations between absorbed doses to specific substructures of the brain and neurocognitive outcomes were present for Wechsler's Adult Intelligence Scale-digit span and Controlled Oral Word Association Test-S. Structural MRI revealed macroscopic abnormalities in three patients; infarction (n = 1), diffuse white matter intensities (n = 2) and necrosis (n = 1). In the analysis of atrophy of cerebral tissue, no correlations were present with neither radiation dose to cerebral substructures nor neurocognitive impairment. The global QoL of the cohort was 75. The most affected outcomes were 'fatigue', 'insomnia', and 'drowsiness'. A total of 59% of participants reported significantly impaired quality of sleep. Self-reported cognitive function revealed that 'memory' was the most affected cognitive domain. For the domains of 'memory' and 'language', self-reported functioning was associated with objectively measured neurocognitive outcomes. CONCLUSION: Cerebral toxicity after radiotherapy for sinonasal cancer was substantial. Clinically significant cognitive impairment was present in more than one third of the participants, and several dose-response associations were present. Furthermore, the presence of macroscopic radiation sequelae indicated considerable impact of radiotherapy on brain tissue.

4.
J Commun Dis ; 30(3): 175-8, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10093425

RESUMO

Intestinal perforation is an extremely uncommon complication of Mycobacterium tuberculosis (MTB) infection. We report a case of HIV infection in a male injecting drug user (IDU) with intestinal tuberculosis complicated with multiple ileal perforations at the Regional Institute of Medical Sciences Hospital, Imphal, Manipur. The emergency surgical therapy supported by antitubercular drugs (ATT) and parenteral nutrition saved the life of this patient who presented in a critical state of shock. The patient manifested with extrapulmonary tuberculosis, which is one of the criteria of AIDS. The authors stress the possibility that in future, tubercular complication till now considered atypical, may become more frequent.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/complicações , Doenças do Íleo/complicações , Perfuração Intestinal/etiologia , Mycobacterium tuberculosis , Tuberculose Gastrointestinal/complicações , Adulto , Humanos , Masculino
6.
Anthropol Anz ; 45(4): 351-60, 1987 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3501697

RESUMO

14 population groups of Sikkim (India)--Lepchas (2), Bhutias (2), Sherpas, Tamangs, Gurungs, Mangars, Rais, Limboos/Subbas, Pradhans (Newars), Brahmans, Chhetris, Scheduled Castes--have been studied in regard of the intra- and intergroup variability of colour blindness, ear lobe attachment, mid-phalangeal hair and behavioural traits (tongue folding, hand clapsing, arm folding, leg folding, handedness). Some of these variables show a considerable distribution heterogeneity, which is discussed considering history and marriage patterns of these populations. As most of them are highly endogamous one can assume that this heterogeneity is caused by locally acting factors such as drift and/or founder effects, which could be preserved due to as good as lacking gene flow among the populations under study. Beyond that the Sikkim data are compared briefly with those reported for other Indian and Asiatic populations.


Assuntos
Defeitos da Visão Cromática/genética , Orelha Externa/anormalidades , Dedos , Lateralidade Funcional , Genética Populacional , Cabelo , Hábitos Linguais , Frequência do Gene , Humanos , Índia
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