Combined Features in Region of Interest for Brain Tumor Segmentation

Diagnosis of brain tumor gliomas is a challenging task in medical image analysis due to its complexity, the less regularity of tumor structures, and the diversity of tissue textures and shapes. Semantic segmentation approaches using deep learning have consistently outperformed the previous methods in this challenging task. However, deep learning is insufficient to provide the required local features related to tissue texture changes due to tumor growth. This paper designs a hybrid method arising from this need, which incorporates machine-learned and hand-crafted features. A semantic segmentation network (SegNet) is used to generate the machine-learned features, while the grey-level co-occurrence matrix (GLCM)-based texture features construct the hand-crafted features. In addition, the proposed approach only takes the region of interest (ROI), which represents the extension of the complete tumor structure, as input, and suppresses the intensity of other irrelevant area. A decision tree (DT) is used to classify the pixels of ROI MRI images into different parts of tumors, i.e. edema, necrosis and enhanced tumor. The method was evaluated on BRATS 2017 dataset. The results demonstrate that the proposed model provides promising segmentation in brain tumor structure. The F-measures for automatic brain tumor segmentation against ground truth are 0.98, 0.75 and 0.69 for whole tumor, core and enhanced tumor, respectively.

The potential and limitations of utilising head impact injury models to assess the likelihood of significant head injury in infants after a fall

The use of engineering principles in assessing head injury scenarios is of increasing significance in investigations into suspected child abuse. A fall scenario is often given as the history for a head injury to an infant. This paper addresses the basic engineering principles and factors to be considered when calculating the severity of a head impact after free-fall. The application of head injury models (HIMs) to ascertain the forces involved in childhood head injuries from impact is also discussed. Previous studies including Duhaime et al. [J. Neurosurg. 66 (1987) 409] and Nokes et al. [Forensic Sci. Int. 79 (1995) 85] have utilised HIMs for this purpose: this paper reviews those models most widely documented.The HIM currently considered the 'state-of-the-art' is the head injury criterion (HIC) and it is suggested that this model should be utilised for assessing head impact injury in child abuse cases where appropriate.

A novel approach to forensic investigation: three-dimensional kinematic and kinetic motion analysis

Following a domestic incident, a five-year-old child was pronounced dead on arrival at hospital. The subsequent post-mortem examination found that the cause of death was peritonitis as a result of a rupture of the duodenum. During the police interview, the main suspect alleged that the injury occurred whilst playing a game which involved standing on the child's abdomen and chest. A reconstruction of the game was performed using 3-dimensional kinematic and kinetic motion analysis to investigate the feasibility of the statement as described by the defendant. Presented is a summary of the investigation together with a description of kinematic and kinetic methods employed.

A biomechanical reconstruction of a wound caused by a glass shard--a case report

During the course of a criminal trial, an investigating pathologist is commonly asked how much force was required to produce an injury. This subjective opinion is based on the pathologist's previous experience of dealing with wounds inflicted with similar weapons. However, in the case of stab wounds inflicted by broken glass, it is unlikely that two glass fragments would be physically similar. In the case studied, two theories were examined: that a wound resulted from a thrown glass fragment or that it had been caused as a stab injury by the glass held in the bare hand. The investigation involved quantifying the energy required for human tissue penetration, comparison of sharpness, a biomechanical analysis of throwing actions and testing of the hypothesis that if the glass shard were used as a stabbing implement it would result in a cut to the hand.The investigation utilised a scientific methodology that reduced the need for speculative (though informed) opinion from the pathologist by producing quantitative results.

Subjective assessment of blunt impacts

An important role of an eyewitness to an assault is to effectively quantify the degree of force used; yet evidence of this form is often subjective and relies on personal opinion. Twelve subjects were asked to strike a load cell with a wooden bat, using varying degrees of force. The strikes were recorded by video camera and 50 people observed the video and were asked to grade the strikes. On average 44% accurately assessed the severity of the strikes, whilst 26% over-estimated. Results suggest that the evidence of eyewitnesses should be treated with caution.

Observation on the recent examination of bones from St David's Cathedral

Bones discovered in 1866 walled up in St David's Cathedral, West Wales were thought possibly to be those of St David and his companion St Justinian, both of whom died in the late 6th or early 7th century. Examination and radio carbon dating of the bones suggested that these were not from St David nor St Justinian. Some of the bones could be the remains of St Caradoc, a 12th century hermit. It is likely, however, that the bones are remains of clergy who, for reasons not yet understood, were re-interred into the wall.

Dynamics of stab wounds: force required for penetration of various cadaveric human tissues

It is often said that once the skin has been penetrated no further force is required to produce penetration of underlying tissues. This experimental study has used technology which was not available to earlier investigators to examine this issue in detail. The results confirm the importance of skin penetration but indicate that the penetration of other tissues may also require significant force.

The use of low-frequency vibration measurement in orthopaedics

This paper reviews the literature regarding the use of applying conventional low-frequency vibration analysis as a possible diagnostic tool in the orthopaedic field. Although a considerable number of investigations have been carried out, including the effects of soft tissue, the technique has not been widely accepted clinically. The application of ultrasound appears to be a more realistic alternative.

The use of ultrasonics in orthopaedics--a review

Ultrasonic testing of bones has been used with varying degrees of success for more than 40 years to determine mechanical properties of bone tissue and strength of whole bones. Ultrasound has also been used in an effort to develop non-invasive techniques for monitoring fracture healing in long bones. Despite early promising results, clinically useful methods have yet to be developed. This paper provides a comprehensive review of the literature of determining mechanical properties of bone and the monitoring of fracture healing.

Biomechanics of judicial hanging: a case report

A prisoner in Washington State in the United States of America appealed against sentence of death by hanging on the grounds that it was 'cruel and unusual' and hence contravened the Eighth Amendment of the US Constitution. The man weighed 184 kg (406 lb) and it was suggested that the 'drop' proposed to effect judicial hanging might result in decapitation. This hypothesis was tested by applying simple biodynamic principles to the available data from past hangings. It was concluded that decapitation was a significant possibility.

Postmortem electrical excitability of skeletal muscle: preliminary investigation of an animal model

Presented is a preliminary study of the feasibility of using an animal model to investigate the postmortem time-dependent decay in muscular response, when subjected to electrical stimulation and to develop an animal model for the assessment of the use of electrical excitability as a method for determining the postmortem period of a human corpse. Analysis of the results shows a correlation between the rate of decay of muscular response with the postmortem interval.

Determination of fracture healing by transverse vibration measurement: a preliminary report

We present results from seven patients with closed mid-shaft tibial fractures and question the hypothesis that transverse wave response ratio analysis could be used to assess the progress of healing fractures. No correlation could be found between the response ratio and the post-fracture time as an indicator of bone fracture healing.

Examination of the eye as a means to determine the early postmortem period: a review of the literature

Reported are various techniques to determine the early postmortem period by examining the eye. These include corneal opacity, retinal vessel segmentation, pupil reaction, retinal changes and intraocular pressure. All are subjective, requiring experience to implement the techniques.

The use of either the nose or outer ear as a means of determining the postmortem period of a human corpse

Presented in this paper are the initial results involving the use of the nose or outer ear as temperature measurement sites to determine the postmortem period of the human corpse. Simple mathematical models for both sites are developed based on cooling curves of five corpses. Analysis of errors between actual and calculated postmortem intervals suggest that in its present form, the described methods would not be suitable for use in accurately determining the time since death of human corpses.

The application of eight reported temperature-based algorithms to calculate the postmortem interval

There exist numerous temperature-based techniques to calculate the early postmortem interval of human corpses. This paper presents eight commonly used time of death algorithms and describes how they were applied to eight corpses.

Detection of internal fixation plate loosening by means of an analysis of vibratory responses

This paper reports an in vitro investigation of a non-invasive method for detecting the loosening of internal fixation plates. The technique involves the electromechanical vibration of the fixation plate and the electromagnetic detection of its vibratory response. Frequency domain analysis of both fixed and loosened plates are compared and spectral artefacts are suggested as a means of classifying the mode and extent of plate loosening. An algorithm for the diagnosis of loose plates using the new approach is included.

Investigations into the analysis of the rate of decay of the compound action potentials recorded from the rat sciatic nerve after death: significance for the prediction of the post-mortem period

There have been a number of papers that have reported the investigations of electrical stimulation of muscle groups in order to determine the post-mortem period. To the authors knowledge, no techniques have been described that analyse the compound action potentials (CAP) of various nerve fibre groups after death. This paper reports the monitoring of both the amplitude and latency changes of the CAP recorded from a stimulated rat sciatic nerve after death. Initial results suggest that the method my be useful in determining the early post-mortem period within 1 or 2 h after death. It may also be of use in measuring nerve conduction delay in various pathological conditions that can affect the neural network; for example diabetes.

Estimation of the post mortem period by multiple-site temperature measurements and the use of a new algorithm

The estimation of the post mortem period, in cases where death occurred under suspicious circumstances, is usually attempted using temperature measurements taken at a single body site. Early investigations of the validity of such an approach use the abdominal skin surface, the axilla and the rectum as measurement sites (B.H. Knight, Forensic Sci. Int., 36 (1987) 47-55). However, it has recently become more common to use the rectum alone, though the ear and the nasal passages have also been utilized. Whatever site is employed, the estimates are frequently found to be inaccurate. There are several fundamental reasons for these inaccuracies, the most prominent being the unknown variation in the ambient temperature between the time of death and the commencement of measurements, and the unknown body temperature at the time of death. This paper proposes a method of overcoming the above difficulties by taking a series of measurements concurrently at a number of body sites, a technique used by several previous workers (B.H. Knight, Forensic Sci. Int., 36 (1987) 47-55). Initial investigations have shown that an improved estimation of post mortem period is obtainable by the application of a suitable decision-making algorithm.

Natural frequency of fracture fragments in the assessment of tibial fracture healing

The natural frequency of fracture fragments has been measured at various times in the course of healing of 11 midshaft tibial fractures. The major fragments manifest different frequencies which are themselves distinct from that of the intact bone. It has been shown that the difference in frequency between the major fragments falls with time, so that the separate frequencies approach a common value which corresponds with the healed state. The results have been used to construct a model healing curve, against which other tibial fractures can be compared.

A self-contained method for determining time since death from temperature measurements

An equation suggested by Brown and Marshall that represented the cooling curve of the human corpse is modified in order to estimate the time of death without resource to lengthy mathematical techniques. A comparison with two other predictive procedures for estimating the time of death is given.