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1.
Heliyon ; 10(1): e23610, 2024 Jan 15.
Article in English | MEDLINE | ID: mdl-38187263

ABSTRACT

Analyzing brain tumours is important for prompt diagnosis and efficient patient care. The morphology of tumours, which includes their size, location, texture, and heteromorphic appearance in medical pictures, makes them difficult to analyse. A unique two-phase deep learning-based framework is suggested in this respect to recognise and classify brain cancers in magnetic resonance images (MRIs). A new DTA approach is suggested in the first phase to successfully identify tumour MRI images from healthy persons. DTA are specifically designed and perform well are used to create the deep boosted feature space, which is then fed into the group of machine learning (ML) classifiers. In the second stage, a brand-new hybrid features fusion-based brain tumour classification technique is put forward, one that makes use of both static and dynamic features as well as an ML classifier to classify various tumour kinds. The proposed algorithm, which can recognise the heteromorphic and variable behaviour of different tumours, is where the dynamic characteristics are taken.In this paper, many segmentation algorithms for MRI and PET are reviewed together with their performance evaluations in order to detect brain tumours. There are numerous segmentation methods available for the diagnosis of medical images. The features of the image, such as the capacity to distinguish between similarities and discontinuities, are often used to classify the segmentation techniques. Neuroradiologists have a difficult issue in trying to quickly identify the abnormal region, which is essential in the medical field. In order to overcome this problem, the efficiency of different segmentation procedures is assessed. The segmentation methods considered here are Ant Colony Optimization (ACO), Wavelet Transform (WT), Gradient Vector Flow (GVF), Gray level Co-occurrence matrix (GLCM), and Artificial Bee Colony (ABC). The various performance metrics are used to evaluate the suggested segmentation algorithms. The GVF strategy works better with MRI images, whereas the ABC and ACO approaches perform similarly with PET scans, according to the data acquired.

2.
J Med Phys ; 33(2): 64-71, 2008 Apr.
Article in English | MEDLINE | ID: mdl-19893693

ABSTRACT

This paper describes the initial experience of quality assurance (QA) tests performed on the millennium multi-leaf collimator (mMLC) for clinical implementation of intensity-modulated radiotherapy (IMRT) using sliding window technique. The various QA tests verified the mechanical and dosimetric stability of the mMLC of linear accelerator when operated in dynamic mode (dMLC). The mechanical QA tests also verified the positional accuracy and kinetic properties of the dMLC. The stability of dMLC was analyzed qualitatively and quantitatively using radiographic film and Omnipro IMRT software. The output stability, variation in output for different sweeping gap widths, and dosimetric leaf separation were measured. Dose delivery with IMRT was verified against the dose computed by the treatment planning system (TPS). Monitor units (MUs) calculated by the planning system for the IMRT were cross-checked with independent commercial dose management software. Visual inspection and qualitative analysis showed that the leaf positioning accuracy was well within the acceptable limits. Dosimetric QA tests confirmed the dosimetric stability of the mMLC in dynamic mode. The verification of MUs using commercial software confirmed the reliability of the IMRT planning system for dose computation. The dosimetric measurements validated the fractional dose delivery.

3.
J Med Phys ; 33(4): 158-61, 2008 Oct.
Article in English | MEDLINE | ID: mdl-19893710

ABSTRACT

For radiotherapy of para-aortic and abdominal regions in male patients, gonads are to be protected to receive less than 2% of the prescribed dose. A testicular shield was fabricated for abdominal radiotherapy with 15 MV X-rays ((Clinac 2300 CD, Varian AG) with low melting point alloy (Cerroband). The dimensions of the testicular shield were 6.5 cm diameter and 3.5 cm depth with 1.5 cm wall thickness. During treatment, this shield was held in position by a rectangular sponge and Styrofoam support. Phantom measurement was carried out with a humanoid phantom and a 0.6 cc ion chamber. The mean energy of the scattered photon was calculated for single scattering at selected distances from the beam edge and with different field dimensions. One patient received radiotherapy with an inverted Y field and gonad doses were estimated using calibrated thermo-luminescent detector (TLD) chips. Measured doses with the ion chamber were 7.1 and 3.5% of the mid-plane doses without a shield at 3 and 7.5 cm off-field respectively. These values decreased to 4.6 and 1.7% with the bottom shield alone, and to 1.7 and 0.8% with both bottom and top shields covering the ion chamber. The measured doses at the gonads during the patient's treatment were 0.5-0.92% for the AP field (0.74 +/- 0.17%, n = 5) and 0.5-1.2% for the PA field (0.88 +/- 0.24%, n = 5). The dose received by the testis for the full course of treatment was 32 cGy (0.8%) for a total mid-plane dose of 40 Gy. The first-scatter energy estimated at the gonads is around 1.14 MeV for a primary beam of 15 MV for a long axis dimension of 37 cm of primary field. During the patient's treatment, the estimated absorbed doses at the gonads were comparable with reported values in similar treatments. The testicular shield reported in this study is of light weight and could be used conveniently in treatments of abdominal fields.

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