Search PubMed⌕ Search

Biomedical subjects

R E Wood

Publications and source records attributed to R E Wood.

At least 19 recordsLinked to original sources
PubMed2006

Forensic aspects of maxillofacial radiology.

Radiology has been used extensively in conventional dental identification, anatomically based identification and identification using maxillofacial skeletal landmarks such as the frontal sinus. Examples of these are well documented in the literature. The purpose of this paper was to revisit the methods where radiographic methods may be used to determine identity using the teeth, the root structures and the frontal sinuses. Additionally suggestions are offered for management of radiography in mass disasters and cases where age determination is required. Computer assisted tomography can be used in the assessment of the degree of fit of a weapon to a wound in cases of blunt force skull injury and plane films can assist in depicting the pattern of post mortem skull fractures. Micro-computed tomography has been used in matching weapons to wounds in sharp-force injury cases. The radiologist's role in cases of civil litigation and fraud is discussed and case examples are given. There are gaps in the science where radiological methods are used. The author offers several suggestions for possible research projects to close some of these gaps.

Age Determination by Teeth↗
PubMed2006

Advances in the diagnosis and management of chronic pulmonary aspiration in children.

Chronic pulmonary aspiration (CPA) in children is an important cause of recurrent pneumonia, progressive lung injury, respiratory disability and death. It is sporadic, intermittent and variable, and often occurs in children with complicated underlying medical conditions and syndromes that produce symptoms indistinguishable from CPA. For most types of aspiration there is no gold-standard diagnostic test. The diagnosis of CPA is currently made clinically with some supporting diagnostic evaluations, but often not until significant lung injury has been sustained. Despite multiple diagnostic techniques, the diagnosis or exclusion of CPA in children is challenging. This is of particular concern given the outcome of unrecognised progressive lung injury and the invasiveness of definitive therapies. Although new techniques have been introduced since the 1990s and significant advances in the understanding of dysphagia and gastro-oesophageal reflux have been made, characterisation of the aspirating child remains elusive.

Child↗
PubMed2006

Clinical and histopathological examination of experimental bite marks in-vivo.

Under rigorously controlled laboratory conditions, mechanically induced simulated human bite marks were made on pig skin to enable the clinical and histopatholgical study of experimental bite marks in-vivo. A series of bite marks were created on the abdomen and thorax of live anaesthetized juvenile pigs at specific times just prior to and after death. Following the release of the biting force clinical observations of antemortem wounds revealed slow diminishment of the bite indentations presumably due to dermal elastic recovery. Minutes after euthanasia of the animals, the indentations of the teeth from the postmortem bite marks faded rapidly. After the biting process the animals were placed on either the right or left side and this side was maintained until necropsy to examine for dependant and non-dependent side differences. All bite mark injuries located on the non-dependent side revealed specific pattern characteristics. However, on the dependent side whether the bite mark was antemortem or postmortem in areas of livor mortis, no clear pattern was visible. Histologically, the observations for each bite mark specimen were categorised by the presence or absence of extravasated red blood cells in the fatty or muscle layers. The histopathological findings correlate with the clinical observations of antemortem and postmortem bite marks located on the non-dependent side in regard to muscular erythema and extravasated red blood cells. It is clinically difficult to comment on temporal relationship of a bite mark in relation to time of death in areas affected by blood-pooling seen on the dependent side. In these situations, histopathological studies could be a reliable alternative to provide information regarding antemortem or postmortem injuries.

Adipose Tissue↗
PubMed2005

Clinical benefits of continuous leukocyte filtration during cardiopulmonary bypass in patients undergoing valvular repair or replacement.

Valve operations in the form of repair or replacement make up a significant population of patients undergoing surgical procedures in the USA annually with the use of cardiopulmonary bypass. These patients experience a wide range of complications that are considered to be mediated by activation of complement and leukocytes. The extracorporeal perfusion circuit consists of multiple synthetic artificial surfaces. The biocompatibility of the blood contact surfaces is a variable that predisposes patients to an increased risk of complement mediation and activation. This can result in an inflammatory process, causing leukocytes to proliferate and sequester in the major organ systems. The purpose of this study was to determine whether filtration of activated leukocytes improved clinical outcomes following surgical intervention for valve repair or replacement. In this paper, we report a retrospective matched cohort study of 700 patients who underwent valve procedures from June 1999 to December 2002. The control group (CG) consisted of patients who had a conventional arterial line filter. In the study group (SG), patients had a conventional arterial line filter and a leukocyte arterial line filter (Pall Medical, NY). In the SG, blood diverted to the cardioplegia system was also leukocyte depleted to enhance myocardial preservation by adapting this device to the outflow port on the filter. Patient characteristics were similar for the SG and the CG, including 228 males and 122 females, mean age (62.4 versus 64.2 years), cardiopulmonary bypass time (127+/-64 versus 116+/-53 min), and aortic crossclamp time (84+/-23 versus 81+/-23 min). Our results demonstrate that the SG achieved statistically significant reduction in the time to extubation (p =0.03) and the number of patients with prolonged intubation in excess of 24 hours (p <0.04), in addition to improved postoperative oxygenation (p=0.01), and decreased length of hospital stay (p =0.03). We believe that leukocyte filters are clinically beneficial, as demonstrated by the results presented in this study.

Cardiopulmonary Bypass↗
PubMed2005

Porcine skin as an in-vivo model for ageing of human bite marks.

Porcine skin has been shown to have similar histological, physiological and immunological properties to human skin and has been suggested as a good analogue for medical and forensic research. This study was undertaken to examine the appearance of bite mark wounds inflicted at known time intervals before and after death. Under general anaesthesia, a series of bite marks were created on a pig's abdomen with a device designed to mechanically produce simulated human bite mark wounds. The pig skin model showed that bite mark characteristics are similar to those found on human skin. This study has provided information on the window of time showing clearly detailed bite marks occurring around the time of death. It also demonstrated that it is possible under certain conditions to determine that a bite mark was made before or after death in a porcine model. Under these experimental conditions, the results suggest that an in-vivo porcine skin model should be considered as a representative model for the study of human bite marks.

Animals↗
PubMed2002

A prospective radiological analysis of fragment displacement in fractures of the mandibular condyle: evaluation of 96 consecutive cases.

A prospective radiological study of 96 patients with mandibular condylar neck fractures was undertaken to assess frequency and nature of mandibular condylar displacement. Data collected included age, gender, aetiology, and anatomical site of fracture and direction of displacement. Men aged 20-29 years sustained the majority of condylar fractures. Assault was the major cause of condylar fracture, followed by motor vehicle accidents and sport accidents. No anterior or posterior displacement of the condyle was noted. Medial displacement of the superior fragment was most frequently observed.

Accidents, Traffic↗
PubMed2001

Prospective analysis of endoscopic vein harvesting.

BACKGROUND: Utilization of bridging vein harvesting (BVH) of saphenous vein grafts (SVG) for coronary artery bypass grafting (CABG) results in large wounds with great potential for pain and infection. Endoscopic vein harvesting (EVH) may significantly reduce the morbidity associated with SVG harvesting. METHODS: A prospective database of 200 matched patients receiving EVH and BVH was compared. The patients all underwent CABG done over a period of 4 months (April to August 2000). Patients were excluded if they had prior vein harvesting. RESULTS: The EVH and BVH group included 100 patients each with similar demographics. The patients in the EVH group had significantly fewer wound complications, mean days to ambulation, and total length of stay (P <0.05). There was no difference in harvest time or vein injuries. CONCLUSION: Endoscopic vein harvesting results in significantly fewer wound complications, decrease in days to ambulation, and the total length of stay. EVH is superior to BVH in patients undergoing CABG.

Coronary Artery Bypass↗
PubMed2001

The emerging role of flexible bronchoscopy in pediatrics.

Great advances had been made in rigid instrumentation, with the introduction of the glass rod telescope. With relatively few exceptions, however, bronchoscopy was still performed primarily for therapeutic indications, such as the removal of foreign bodies from the airway. It would remain for the introduction of the flexible bronchoscope to stimulate the widespread development of diagnostic bronchoscopy in pediatric practice.

Bronchi↗
PubMed2001

Impact of guided exploration and enactive exploration on self-regulatory mechanisms and information acquisition through electronic search.

Following instruction in basic skills for electronic search, participants who practiced in a guided exploration mode developed stronger self-efficacy and greater satisfaction than those who practiced in a self-guided exploratory mode. Intrinsic motivation was not affected by exploration mode. On 2 post-training tasks, guided exploration participants produced more effective search strategies. expended less effort, made fewer errors, rejected fewer lines of search, and achieved higher performance. Relative lack of support for self-regulatory factors as mediators of exploration mode impacts was attributed to the uninformative feedback from electronic search, which causes most people to remain at a novice level and to require external guidance for development of self-efficacy and skills. Self-guided learning will be more effective on structured tasks with more informative feedback and for individuals with greater expertise on dynamic tasks.

Databases as Topic↗
PubMed2001

Does the lead apron and collar always reduce radiation dose?

The possibility that personal lead shielding devices can increase absorption of radiation has not been entertained. The purpose of the present investigation specifically was to determine whether pituitary dose might be increased when a leaded apron and thyroid collar are used. Thermoluminescent dosimeters (TLDs) were used to measure absorbed dose. They were calibrated at the kVp used in the clinical situation and a calibration curve relating light output to dose was generated. Lithium fluoride TLD discs were placed in the pituitary gland region of a Rando-Alderson female human phantom. The equivalent of 100 transpharyngeal exposures were delivered. The resultant light output from recovered dosimeters was converted to a uGy value using the calibration curve. The experiment was repeated using a 0.25 mm lead equivalent collar and apron fitted to the phantom in the customary manner. The entire process was repeated in order to have 30 dosimeters for the unshielded and 30 dosimeters for the shielded conditions. A further 30 dosimeters were sham irradiated and served as controls. A statistical comparison between unshielded and shielded conditions was performed. When the leaded apron and thyroid collar were used the absorbed dose to the pituitary gland was increased significantly (P < 0.05). Following this a second group, using a different dosimetry system and a male phantom repeated the experiment. In both cases, the shielded phantom received significantly higher dose to the pituitary region than the unshielded.

Absorption↗
PubMed2001

Extranodal non-Hodgkin's lymphoma of the maxillofacial region: analysis of 88 consecutive cases.

Examination of the records of 88 consecutive patients with extranodal maxillofacial non-Hodgkin's lymphoma (ENHL) was undertaken. Each patient's complete record was reviewed. Males outnumbered females by 1.7:1. Age at diagnosis ranged from 22 to 94 years (median 60.0). Affected anatomic sites included: maxillary sinus (22), nasal cavity (8), maxilla (13), mandible (8), salivary glands (14), and other (23). The most common presenting symptom was a non-painful mass. Associated dental symptoms were present in 72 patients and included intraoral swelling, pain, and loose teeth. Treatment included chemotherapy and radiation with a follow-up of 1-25 years. Treatment trends indicate a shift towards multimodal therapy. Non-Hodgkin's lymphoma of the head and neck, if discovered early, has an excellent prognosis.

Adult↗
PubMed2000

Tooth root colour as a measure of chronological age.

The purpose of this study was to assess a possible colour shift in the root surfaces of adult human teeth and if so, whether this colour change is related to chronological age. Teeth extracted from persons of known age and gender were obtained from Ontario dental practitioners and grouped into five-year age ranges. Three experiments were undertaken: (1) to identify a possible difference in yellow colouration between the four surfaces of tooth roots (mesial, distal, lingual, and buccal), (2) to investigate the difference in yellow colouration of tooth roots between non-molar teeth and molar teeth and (3) to assess the correlation between the age of teeth and root colour saturation for yellow, magenta, cyan and black. The teeth in all investigations were scanned by a flat-bed digital colour scanner with a Kodak colour scale control and viewed on a colour computer monitor. In the first two experiments the yellow colour saturation of the root surfaces was measured at six points on each root using Photoshop 5.0 software. A significant difference was observed in the percentage yellow colour saturation between the mesial and the other three anatomical surfaces (p < 0.01), and between the root surfaces of non-molar and molar teeth (p < 0.01) (ANOVA with Bonferroni post-test). The authors then randomly assigned tooth surfaces to select an equivalent number of posterior and anterior teeth in the study, assessing the relationship between age and root colouration. Four points of colour measurement on 40 teeth (sample size permitting, see Table 1) for each known age and gender were assessed for colour saturation (cyan, magenta, yellow and black). The correlation of chronological age to colour saturation was linear for all colours, with correlation coefficients ranging from r = 0.81 to r = 0.94. The high correlation values strongly support the conclusion that chronological age is related to increased root colouration.

Adolescent↗
PubMed1999

Operative therapy of coronary arterial aneurysm.

In summary, a patient with multiple coronary aneurysms and operative therapy is described and 17 previously reported similar cases are reviewed. The proper type of operation for this condition is as yet unclear, but, nevertheless, the reported cases and our case with operative therapy have done well postoperatively despite a variety of procedures performed.

Aged↗
PubMed1999

The effects of antitumor irradiation on mandibular opening and mobility: a prospective study of 58 patients.

OBJECTIVE: The purpose of this study was to analyze the effects of head and neck radiation therapy on jaw opening and mobility. STUDY DESIGN: Maximum jaw opening and mandibular mobility were measured before and after radiation treatment in 58 patients presenting for angle down wedge, homolateral wedge pair, and parallel pair head and neck radiation treatment. RESULTS: As dose to the temporomandibular joint and pterygoid muscles increased, maximal jaw opening decreased linearly. Mandibular dysfunction appeared to increase as radiation dose to the pterygoid muscles increased. Similar effects were not observed with temporomandibular joint irradiation. Irradiation of the pterygoid muscles appeared critical in the development of trismus. Angle down wedge treatment irradiated the temporomandibular joint and pterygoid muscles with clinical effects similar to those seen in homolateral wedge pair and parallel pair patients. Doses as low as 1493 cGy resulted in functional impairment. CONCLUSIONS: Future investigations into radiotherapy delivery and appropriate postradiation trismus treatment may reduce head and neck radiation morbidity.

Analysis of Variance↗
PubMed1999

Optimum dental radiography in bone marrow transplant patients.

OBJECTIVE: The purpose of this study was to establish an optimum radiographic examination regimen for patients undergoing bone marrow transplantation. Two radiographic examinations were compared: the panoramic radiograph and the full mouth series of radiographs. STUDY DESIGN: A prospective analysis of 65 consecutive patients undergoing bone marrow transplantation was undertaken. All patients were examined through use of both panoramic and full mouth series intraoral radiographs, including bitewings. Significant findings were recorded and compared by means of paired t test analysis for parametric data, such as caries, periapical inflammation and subgingival calculus, and by means of McNemar's test for nonparametric data, such as the presence or absence of severe periodontal disease. RESULTS: Acquired findings, such as caries, periodontal disease, and clinically significant faulty restorations, were detected more frequently from the full mouth series (P < .05). There was no significant difference in the detection of periapical pathosis. In 8 of 65 patients, clinically significant information, such as evidence of impacted wisdom teeth, neoplasms, and multiple myeloma, was better detected from the panoramic radiographs. CONCLUSIONS: The results suggest a combination of both modalities as the optimum means of radiologic survey in this "high-risk" patient population.

Adolescent↗
PubMed1999

Potential for fraudulent use of digital radiography.

BACKGROUND: Digital radiographic images can be manipulated using personal computers. To test the potential for fraudulent use, the authors altered a series of dental radiographs, printed them to simulate duplicated films and submitted them for authorization of proposed treatment. MATERIALS AND METHODS: The authors obtained periapical radiographs of teeth that contained small restorations or were unrestored from the files of three dental patients at a private dental practice. The authors used a flatbed scanner to digitize and import the radiographs into a computer. Then they added dental caries, large restorations, fractures and periapical pathosis to the radiographs. The authors proposed to the insurance companies that the teeth in question be restored using expensive treatment, such as root-canal therapy and full-coverage crowns. RESULTS: In each case, the insurance companies authorized the proposed treatment based on the appearance of the teeth on the radiographs. The altered images illustrated an apparent need for dental treatment that was not required and that could have led to payment for treatment that was not actually performed. CONCLUSIONS: This study illustrates the potential for the fraudulent use of manipulated digital radiographic images. CLINICAL IMPLICATIONS: Dentistry should be aware of the implications of the potential for such abuse and should develop measures both to prevent it from occurring and to facilitate its detection.

Computer Security↗