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1.
AJNR Am J Neuroradiol ; 45(2): 139-148, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38164572

RESUMO

Resting-state (rs) fMRI has been shown to be useful for preoperative mapping of functional areas in patients with brain tumors and epilepsy. However, its lack of standardization limits its widespread use and hinders multicenter collaboration. The American Society of Functional Neuroradiology, American Society of Pediatric Neuroradiology, and the American Society of Neuroradiology Functional and Diffusion MR Imaging Study Group recommend specific rs-fMRI acquisition approaches and preprocessing steps that will further support rs-fMRI for future clinical use. A task force with expertise in fMRI from multiple institutions provided recommendations on the rs-fMRI steps needed for mapping of language, motor, and visual areas in adult and pediatric patients with brain tumor and epilepsy. These were based on an extensive literature review and expert consensus.Following rs-fMRI acquisition parameters are recommended: minimum 6-minute acquisition time; scan with eyes open with fixation; obtain rs-fMRI before both task-based fMRI and contrast administration; temporal resolution of ≤2 seconds; scanner field strength of 3T or higher. The following rs-fMRI preprocessing steps and parameters are recommended: motion correction (seed-based correlation analysis [SBC], independent component analysis [ICA]); despiking (SBC); volume censoring (SBC, ICA); nuisance regression of CSF and white matter signals (SBC); head motion regression (SBC, ICA); bandpass filtering (SBC, ICA); and spatial smoothing with a kernel size that is twice the effective voxel size (SBC, ICA).The consensus recommendations put forth for rs-fMRI acquisition and preprocessing steps will aid in standardization of practice and guide rs-fMRI program development across institutions. Standardized rs-fMRI protocols and processing pipelines are essential for multicenter trials and to implement rs-fMRI as part of standard clinical practice.


Assuntos
Neoplasias Encefálicas , Epilepsia , Humanos , Criança , Adulto , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Epilepsia/diagnóstico por imagem , Epilepsia/cirurgia , Idioma , Encéfalo/diagnóstico por imagem
2.
AJNR Am J Neuroradiol ; 41(4): 573-578, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32217553

RESUMO

Polymorphous low-grade neuroepithelial tumors of the young (PLNTYs) are recently described CNS tumors. Classically, PLNTYs are epileptogenic and are a subtype of a heterogeneous group of low-grade neuroepithelial tumors that cause refractory epilepsy, such as angiocentric gliomas, oligodendrogliomas, gangliogliomas, and pleomorphic xanthoastrocytomas. Although they are a relatively new entity, a number of imaging and histologic characteristics of PLNTYs are already known. We present the imaging and pathologic findings of such a tumor as well as the surgical approach and clinical management.


Assuntos
Neoplasias Encefálicas/patologia , Neoplasias Neuroepiteliomatosas/patologia , Adulto , Neoplasias Encefálicas/cirurgia , Calcinose , Feminino , Humanos , Neoplasias Neuroepiteliomatosas/cirurgia , Procedimentos Neurocirúrgicos
3.
AJNR Am J Neuroradiol ; 38(10): E65-E73, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28860215

RESUMO

INTRODUCTION: Functional MR imaging is increasingly being used for presurgical language assessment in the treatment of patients with brain tumors, epilepsy, vascular malformations, and other conditions. The inherent complexity of fMRI, which includes numerous processing steps and selective analyses, is compounded by institution-unique approaches to patient training, paradigm choice, and an eclectic array of postprocessing options from various vendors. Consequently, institutions perform fMRI in such markedly different manners that data sharing, comparison, and generalization of results are difficult. The American Society of Functional Neuroradiology proposes widespread adoption of common fMRI language paradigms as the first step in countering this lost opportunity to advance our knowledge and improve patient care. LANGUAGE PARADIGM REVIEW PROCESS: A taskforce of American Society of Functional Neuroradiology members from multiple institutions used a broad literature review, member polls, and expert opinion to converge on 2 sets of standard language paradigms that strike a balance between ease of application and clinical usefulness. ASFNR RECOMMENDATIONS: The taskforce generated an adult language paradigm algorithm for presurgical language assessment including the following tasks: Sentence Completion, Silent Word Generation, Rhyming, Object Naming, and/or Passive Story Listening. The pediatric algorithm includes the following tasks: Sentence Completion, Rhyming, Antonym Generation, or Passive Story Listening. DISCUSSION: Convergence of fMRI language paradigms across institutions offers the first step in providing a "Rosetta Stone" that provides a common reference point with which to compare and contrast the usefulness and reliability of fMRI data. From this common language task battery, future refinements and improvements are anticipated, particularly as objective measures of reliability become available. Some commonality of practice is a necessary first step to develop a foundation on which to improve the clinical utility of this field.


Assuntos
Algoritmos , Mapeamento Encefálico/métodos , Idioma , Imageamento por Ressonância Magnética/métodos , Cuidados Pré-Operatórios/normas , Adulto , Encefalopatias/cirurgia , Mapeamento Encefálico/normas , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética/normas , Masculino , Cuidados Pré-Operatórios/métodos , Reprodutibilidade dos Testes , Estados Unidos
4.
Arch Gynecol Obstet ; 295(1): 103-109, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27619683

RESUMO

INTRODUCTION: Pelvic floor ultrasound plays a major role in urogynecologic diagnostics. Using 3D ultrasound we can identify integrity of levator ani and measure hiatal area in the axial plane. The main goal of our study was to measure hiatal area on Valsalva in a cohort of urogynecological patients. Furthermore, we aimed to correlate hiatal area with urogynecological symptoms, levator integrity and evaluate cut-off values for pelvic organ prolapse. MATERIALS AND METHODS: In a retrospective analysis, we included 246 patients seen for urogynecological problems in our tertiary urogynecological unit. After a standardized interview and physical examination, a 3D pelvic floor ultrasound was performed. According to the cardinal urogynecological symptoms and signs, patients were categorized into three groups: pelvic organ prolapse, stress urinary incontinence and overactive bladder symptoms. RESULTS: Median age of our study population was 66 (range 29-94) years, median parity was 2.1 (range 0-9) with 17 (6.9 %) nulliparous women. Symptoms of overactive bladder in 71.1 % were most common, followed by 54.5 % symptoms of stress incontinence and 32.1 % symptoms of prolapse. On examination 49.2 % showed signs of prolapse. Levator avulsions on 3D ultrasound were detected in 20.7 %. Hiatal area was normally distributed with a median of 28.7 cm2 (range 10.4-50.0 cm2). Patients with levator avulsion had a significantly larger hiatal area (p < 0.001). Also patients with signs of prolapse had a significantly larger hiatal area (p < 0.001). There was no correlation between hiatal area and symptoms of overactive bladder (p = 0.374). Although not reaching statistical significance there was evidence of a smaller hiatal area for patients with stress incontinence (p = 0.016). In our cohort there were 33.7 % (83) women without ballooning, 27.2 % (67) showed mild, 18.3 % (45) moderate, 12.3 % (30) marked and 8.5 % (21) severe ballooning. The ROC curve analysis for hiatal area on patients with prolapse yielded an AUC of 0.755 [95 % CI (0.696-0.814)]. Using the Youden-Index we obtained 27.53 cm2 as a cut-off with a sensitivity of 0.70 and a specificity of 0.69. DISCUSSION: Hiatal area is a new repeatable diagnostic parameter. Its clinical application could improve our understanding of the pathophysiology of pelvic organ prolapse as a form of hiatal hernia.


Assuntos
Diafragma da Pelve/fisiopatologia , Prolapso de Órgão Pélvico/complicações , Ultrassonografia/métodos , Incontinência Urinária por Estresse/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Distúrbios do Assoalho Pélvico/complicações , Estudos Retrospectivos
5.
AJNR Am J Neuroradiol ; 36(6): E41-51, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25907520

RESUMO

MR perfusion imaging is becoming an increasingly common means of evaluating a variety of cerebral pathologies, including tumors and ischemia. In particular, there has been great interest in the use of MR perfusion imaging for both assessing brain tumor grade and for monitoring for tumor recurrence in previously treated patients. Of the various techniques devised for evaluating cerebral perfusion imaging, the dynamic susceptibility contrast method has been employed most widely among clinical MR imaging practitioners. However, when implementing DSC MR perfusion imaging in a contemporary radiology practice, a neuroradiologist is confronted with a large number of decisions. These include choices surrounding appropriate patient selection, scan-acquisition parameters, data-postprocessing methods, image interpretation, and reporting. Throughout the imaging literature, there is conflicting advice on these issues. In an effort to provide guidance to neuroradiologists struggling to implement DSC perfusion imaging in their MR imaging practice, the Clinical Practice Committee of the American Society of Functional Neuroradiology has provided the following recommendations. This guidance is based on review of the literature coupled with the practice experience of the authors. While the ASFNR acknowledges that alternate means of carrying out DSC perfusion imaging may yield clinically acceptable results, the following recommendations should provide a framework for achieving routine success in this complicated-but-rewarding aspect of neuroradiology MR imaging practice.


Assuntos
Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Neurologia/normas , Imagem de Perfusão/métodos , Radiologia/normas , Humanos , Neurologia/métodos , Radiologia/métodos
6.
Strahlenther Onkol ; 190(8): 753-7, 2014 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-24805160

RESUMO

In 1994 and 1998 reports on staffing levels in medical radiation physics for radiation therapy were published by the "Deutsche Gesellschaft für Medizinische Physik" (DGMP, German Society for Medical Physics). Because of the technical and methodological progress, changes in recommended qualifications of staff and new governmental regulations, it was necessary to establish new staffing levels. The data were derived from a new survey in clinics. Some of the previously established results from the old reports were adapted to the new conditions by conversion.The staffing requirements were normalized to main components as in the earlier reports resulting in a simple method for calculation of staffing levels. The results were compared with the requirements in the "Richtlinie Strahlenschutz in der Medizin" (guidelines on radiation protection in medicine) and showed satisfactory agreement.


Assuntos
Fidelidade a Diretrizes , Física Médica , Avaliação das Necessidades/estatística & dados numéricos , Admissão e Escalonamento de Pessoal/estatística & dados numéricos , Proteção Radiológica , Radioterapia de Intensidade Modulada/estatística & dados numéricos , Alemanha , Humanos , Equipe de Assistência ao Paciente , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada/métodos , Recursos Humanos , Adulto Jovem
7.
AJNR Am J Neuroradiol ; 34(9): 1836-40, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23557956

RESUMO

BACKGROUND AND PURPOSE: In an effort to reduce radiation exposure in children requiring regular follow up for shunted hydrocephalus, our institution implemented a rapid brain MR imaging protocol. The purpose of this study was to review an academic practice experience with pediatric rapid brain MR imaging without patient sedation in the evaluation of hydrocephalus and a limited group of other conditions. MATERIALS AND METHODS: We retrospectively analyzed limited-sequence, rapid brain MR imaging scans performed in nonsedated patients younger than 14 years between April 2009 and December 2011. So-called failed examinations were determined by consensus of 2 authors as insufficiently diagnostic for evaluation of ventricular size. CT and MR imaging quarterly volumes for hydrocephalus-related indications were determined from 2005-2012. Multivariable logistic regression analysis was performed to elucidate factors potentially affecting scan durations including examination indication and patient age, sex, inpatient status, and clinical conditions. RESULTS: A total of 398 examinations were performed on 168 patients (103 boys, 65 girls; median age, 13 months). None were deemed to be failed examinations. Median scan duration was 4.43 minutes (interquartile range, 4.42 minutes-5.88 minutes; SD, 2.42 minutes). Examination indication of altered mental status was the only factor associated with increased scan duration (+1.77 minutes; P = .0021). Hydrocephalus-related imaging volumes approximately doubled in the 7 years reviewed, but rapid MR imaging introduced in 2009 is quickly replacing CT scanning for these indications, accounting for nearly 7 of every 8 examinations at the end of the study period. CONCLUSIONS: In every case of initial work-up and follow-up, rapid brain MR imaging effectively evaluated ventricular size and/or intracranial fluid and represents a viable alternative to CT scanning, irrespective of a child's age or clinical condition. For this indication and patient group, MR imaging is now the predominant imaging method in our practice.


Assuntos
Centros Médicos Acadêmicos/estatística & dados numéricos , Hidrocefalia/epidemiologia , Hidrocefalia/patologia , Imageamento por Ressonância Magnética/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Doses de Radiação , Proteção Radiológica/estatística & dados numéricos , Encéfalo , Humanos , Lactente , Minnesota/epidemiologia , Pediatria/estatística & dados numéricos , Prevalência , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Risco , Sensibilidade e Especificidade , Fatores de Tempo , Carga de Trabalho/estatística & dados numéricos
8.
AJNR Am J Neuroradiol ; 32(6): E107-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20595367

RESUMO

We have encountered 2 cases of parathyroid adenomas that are atypical because of their large size, cystic character, and faint enhancement compared with the typical solid parathyroid adenomas. Specifically, the enhancement pattern of a typical parathyroid adenoma in a multiphasic scan demonstrates rapid arterial enhancement and rapid washout on delayed imaging, whereas, comparatively, the 2 cystic parathyroid adenomas we encountered demonstrated less arterial phase enhancement and little washout on venous and delayed-phase imaging.


Assuntos
Cistadenoma/diagnóstico por imagem , Cistadenoma/cirurgia , Neoplasias das Paratireoides/diagnóstico por imagem , Neoplasias das Paratireoides/cirurgia , Tomografia Computadorizada por Raios X/métodos , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Resultado do Tratamento
9.
AJNR Am J Neuroradiol ; 29(6): 1142-3, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18372420

RESUMO

Electrical injuries are becoming more common and are increasingly imaged with advanced technologies, such as MR imaging. However, the MR imaging findings of such injuries remain largely unstudied. We report a high-voltage electrical injury to the cerebral corticospinal tracts and document evolution on serial MR images.


Assuntos
Infarto Encefálico/etiologia , Infarto Encefálico/patologia , Traumatismos por Eletricidade/complicações , Imageamento por Ressonância Magnética/métodos , Tratos Piramidais/lesões , Tratos Piramidais/patologia , Adulto , Humanos , Masculino
10.
Neuroscience ; 145(2): 676-85, 2007 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-17239544

RESUMO

Deletion of transient receptor potential vanilloid type 1 (TRPV1)-expressing afferent neurons reduces presynaptic mu opioid receptors but paradoxically potentiates the analgesic efficacy of mu opioid agonists. In this study, we determined if removal of TRPV1-expressing afferent neurons by resiniferatoxin (RTX), an ultrapotent capsaicin analog, influences the development of opioid analgesic tolerance. Morphine tolerance was induced by daily intrathecal injections of 10 microg of morphine for 14 consecutive days or by daily i.p. injections of 10 mg/kg of morphine for 10 days. In vehicle-treated rats, the effect of intrathecal or systemic morphine on the mechanical withdrawal threshold was gradually diminished within 7 days. However, the analgesic effect of intrathecal and systemic morphine was sustained in RTX-treated rats at the time the morphine effect was lost in the vehicle group. Furthermore, the mu opioid receptor-G protein coupling in the spinal cord was significantly decreased ( approximately 22%) in vehicle-treated morphine tolerant rats, but was not significantly altered in RTX-treated rats receiving the same treatment with morphine. Additionally, there was a large reduction in protein kinase Cgamma-immunoreactive afferent terminals in the spinal dorsal horn of RTX-treated rats. These findings suggest that loss of TRPV1-expressing sensory neurons attenuates the development of morphine analgesic tolerance possibly by reducing mu opioid receptor desensitization through protein kinase Cgamma in the spinal cord. These data also suggest that the function of presynaptic mu opioid receptors on TRPV1-expressing sensory neurons is particularly sensitive to down-regulation by mu opioid agonists during opioid tolerance development.


Assuntos
Tolerância a Medicamentos/fisiologia , Morfina/farmacologia , Neurônios Aferentes/metabolismo , Dor/metabolismo , Células do Corno Posterior/metabolismo , Canais de Cátion TRPV/metabolismo , Analgésicos Opioides/farmacologia , Animais , Diterpenos/toxicidade , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/fisiologia , Masculino , Degeneração Neural/induzido quimicamente , Neurônios Aferentes/efeitos dos fármacos , Nociceptores/efeitos dos fármacos , Nociceptores/metabolismo , Dor/tratamento farmacológico , Dor/fisiopatologia , Limiar da Dor/efeitos dos fármacos , Limiar da Dor/fisiologia , Células do Corno Posterior/efeitos dos fármacos , Proteína Quinase C/efeitos dos fármacos , Proteína Quinase C/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/efeitos dos fármacos , Receptores Acoplados a Proteínas G/metabolismo , Receptores Opioides mu/efeitos dos fármacos , Receptores Opioides mu/metabolismo , Canais de Cátion TRPV/genética
11.
AJNR Am J Neuroradiol ; 27(7): 1483-5, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16908563

RESUMO

Pleomorphic adenomas (PAs), also known as benign mixed tumors, are common tumors of the parotid gland. These tumors occasionally undergo malignant transformation, with potentially devastating consequences. This case report presents the clinical and radiographic features of a rare case of biopsy proved brain and spinal cord metastases arising from carcinoma ex PA of the parotid gland.


Assuntos
Adenocarcinoma/secundário , Adenoma Pleomorfo/patologia , Neoplasias Encefálicas/secundário , Neoplasias Primárias Múltiplas/patologia , Neoplasias Parotídeas/patologia , Neoplasias da Medula Espinal/secundário , Adenocarcinoma/patologia , Adulto , Evolução Fatal , Humanos , Metástase Linfática/patologia , Imageamento por Ressonância Magnética , Masculino , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias
12.
AJNR Am J Neuroradiol ; 27(6): 1292-4, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16775282

RESUMO

We present our initial experience with the use of a modified 3-point Dixon technique to obtain reliable fast spin-echo T1- and T2-weighted fat-suppressed images in the soft-tissue neck. The method has less sensitivity to magnetic field inhomogeneity than frequency-selective radiofrequency fat saturation and provides uniform fat suppression even near tissue-tissue and air-tissue interfaces. Clinical advantages and limitations of the method are discussed and several examples are shown.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Humanos , Pescoço/patologia , Neoplasias de Tecidos Moles/diagnóstico
13.
Rofo ; 176(3): 392-7, 2004 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-15026953

RESUMO

To get a general idea of the actual staffing situation in medical radiation physics, all active members of the German Society of Medical Physics (DGMP) were surveyed by the task force "staff requirements" ("Personalbedarf") of the DGMP in 1999. Of the 322 forms sent out, 173 could be evaluated. The staff requirements in medical radiation physics were calculated from the major elements of the radiology equipment and from the staff responsibilities as defined in the DGMP Reports 8 and 10, and compared with the actual number of staff members. The data of this spot check were then extrapolated for the entire Federal Republic of Germany. The calculation revealed a deficit of 89% for the entire staff in diagnostic radiology and of 84% for physicists. Considering the age distribution of the DGMP members, a training capacity of about 100 medical physicists per year is needed to eliminate the calculated deficit within the next 10 years.


Assuntos
Física Médica , Medicina Nuclear , Radiologia , Alemanha , Humanos , Proteção Radiológica , Radiografia , Sistemas de Informação em Radiologia , Inquéritos e Questionários , Suíça , Recursos Humanos
15.
Radiology ; 221(1): 11-25, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11568316

RESUMO

Radio-frequency coils play a crucial role in the quest for optimal magnetic resonance (MR) image resolution. Given the growing variety of specialized coils available for neuroradiologic imaging applications, it is critical that radiologists use a coherent strategy for successfully matching these coils to specific imaging situations. First, fundamental concepts of coil design are reviewed. Subsequently, a coil-selection algorithm for neuroimaging applications is described. The algorithm uses the patient's clinical history to derive a region of interest, a desired spatial resolution, and a desired contrast resolution. These factors are then used to impose anatomic coverage and imaging protocol constraints on the set of available coils. Finally, coil selection is further refined according to patient tolerance factors. The following coils are considered for use with a 1.5-T superconducting MR imager; namely, quadrature birdcage head, neurovascular phased-array, and dual single-circular-element coils, as well as investigational coils that have not yet been approved by the U.S. Food and Drug Administration: reduced-volume birdcage end-cap, temporal lobe phased-array, carotid artery phased-array, coils. Rationales are discussed regarding appropriate coil selection for screening whole brain and imaging brainstem, cranial nerves, orbits, cerebral cortex, mesial temporal lobes, and internal auditory canal, and for MR angiography.


Assuntos
Encéfalo/anatomia & histologia , Imageamento por Ressonância Magnética/instrumentação , Base do Crânio/anatomia & histologia , Algoritmos , Desenho de Equipamento , Humanos , Anamnese
16.
Otolaryngol Head Neck Surg ; 118(1): 6-8, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9450821

RESUMO

Herein we report what we believe to be the only published case of an intracranial complication of otomastoiditis resulting from foreign-body material. The presence of a foreign body must be ruled out in any chronically draining ear, and all foreign material must be removed. The key to minimizing the morbidity of complications of infectious ear disease is early recognition and treatment. Early symptoms of complication include vertigo, new onset of headache or otalgia, or worsening headache or otalgia. Fever, malodorous ear drainage, and the presence of granulation tissue are warming findings. A high index of suspicion of infectious complications must be maintained in evaluating all patients with ear disease.


Assuntos
Abscesso Encefálico/etiologia , Corpos Estranhos/complicações , Mastoidite/etiologia , Meningite/etiologia , Bactérias Anaeróbias , Evolução Fatal , Feminino , Humanos , Pessoa de Meia-Idade
17.
Strahlenther Onkol ; 172(3): 148-53; discussion 154-5, 1996 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-8721263

RESUMO

METHODS AND RESULTS: Using a questionnaire, mean occupation time values for the different medical physics activities were derived in 1992; they formed the basis for recommendations of minimum physics staffing levels in radiotherapy. The recommended staffing levels were compared with the actual staffing levels and to other national and international recommendations.


Assuntos
Física Médica , Admissão e Escalonamento de Pessoal , Radioterapia , Alemanha , Física Médica/economia , Física Médica/estatística & dados numéricos , Humanos , Admissão e Escalonamento de Pessoal/economia , Radioterapia/economia , Radioterapia/estatística & dados numéricos , Recursos Humanos
18.
Radiobiol Radiother (Berl) ; 31(1): 39-45, 1990.
Artigo em Alemão | MEDLINE | ID: mdl-2343081

RESUMO

The irradiation of tumors in thoracal area presupposes an exact irradiation planning including the lung to prevent therapy limiting dosage errors. With it the exact dimension and the density of the lung have to be known. It was investigated of which factors the lung density depends on and how they affect the dosage precision. Within the lung the density fluctuates considerably; these fluctuations are different from patient to patient and depend on age among other things. This age dependence can be represented by a regression straight line; with this the lung density of patients can be found out from age approximatively. Individual investigation of density from CT-sections can improve precision of dose calculation up to 4%. It has to pay attention to producing CT-sections with normal respiration and in such position as the later irradiation shall be done in.


Assuntos
Pulmão/patologia , Planejamento da Radioterapia Assistida por Computador , Radioterapia Assistida por Computador , Neoplasias Torácicas/radioterapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/patologia , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Radiobiol Radiother (Berl) ; 30(2): 107-12, 1989.
Artigo em Alemão | MEDLINE | ID: mdl-2748800

RESUMO

In a collective of 70 patients with bone metastases the importance of CT for detection and extension diagnosis is shown. In 53% CT proved the scintigraphic and/or roentgenologic suspicion. In 30% CT gave more information than scintigraphy and plain radiography, but without any influence in the treatment. In 17% only CT gave such important information, that the planned treatment must be changed. The results led to the conclusion, that CT can be important for the optimization of radiological treatment.


Assuntos
Neoplasias Ósseas/secundário , Planejamento da Radioterapia Assistida por Computador , Radioterapia Assistida por Computador , Tomografia Computadorizada por Raios X , Neoplasias Ósseas/diagnóstico por imagem , Humanos
20.
Ann Otol Rhinol Laryngol ; 98(1 Pt 1): 37-40, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2910186

RESUMO

Most attempts at laryngeal reconstruction have sought to reestablish skeletal support. Bone and cartilage grafts have been used for this purpose, but they have often failed to maintain position in the larynx and/or trachea following reconstruction, and they tend to be reabsorbed. The rotary door flap can provide an undelayed, one-stage epithelial resurfacing of the larynx and trachea while simultaneously restoring luminal support without the need for transfer of cartilage or bone. Luminal support for the trachea is provided by the bulk, turgor, and anterior traction of the intact sternohyoid muscle, which serves as the carrier for the rotated skin island. During inspiration the intact muscle, whose points of attachment are anterior to the plane of the larynx and trachea, contracts and tends to open the airway to provide dynamic luminal support. The need for internal stenting is minimized. The technique is described and experience in 20 patients is presented.


Assuntos
Laringe/cirurgia , Retalhos Cirúrgicos , Traqueia/cirurgia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Humanos , Lactente , Músculos Laríngeos/cirurgia , Neoplasias Laríngeas/cirurgia , Laringoestenose/cirurgia , Pessoa de Meia-Idade , Complicações Pós-Operatórias
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