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P Michele Williams

Publications and source records attributed to P Michele Williams.

8 recordsLinked to original sources

Direct fluorescence visualization of clinically occult high-risk oral premalignant disease using a simple hand-held device.

BACKGROUND: A considerable proportion of oral cancer and precancer is not clinically apparent and could contribute significantly to the late diagnosis and high mortality of oral cancer. A simple method to identify such occult change is needed. METHODS: Patients in the Oral Dysplasia Clinics at British Columbia are currently being examined with a simple hand-held device that permits the direct visualization of alterations to autofluorescence in the oral cavity. Tissue showing loss of autofluorescence is biopsied. RESULTS: We present 3 representative cases in which occult lesions were identified with fluorescence visualization during longitudinal follow-up, resulting in the diagnosis of a primary dysplasia in case 1, a second primary cancer in case 2, and cancer recurrence in case 3. CONCLUSIONS: This is the first report of the diagnosis of occult oral disease using a simple noninvasive device. These early examples indicate the potential value of this technology to guide the management of patients with oral lesions, facilitating the detection of high-risk changes not apparent with white-light visualization.

Adult↗

Fluorescence visualization detection of field alterations in tumor margins of oral cancer patients.

PURPOSE: Genetically altered cells could become widespread across the epithelium of patients with oral cancer, often in clinically and histologically normal tissue, and contribute to recurrent disease. Molecular approaches have begun to yield information on cancer/risk fields; tissue optics could further extend our understanding of alteration to phenotype as a result of molecular change. EXPERIMENTAL DESIGN: We used a simple hand-held device in the operating room to directly visualize subclinical field changes around oral cancers, documenting alteration to fluorescence. A total of 122 oral mucosa biopsies were obtained from 20 surgical specimens with each biopsy being assessed for location, fluorescence visualization (FV) status, histology, and loss of heterozygosity (LOH; 10 markers on three regions: 3p14, 9p21, and 17p13). RESULTS: All tumors showed FV loss (FVL). For 19 of the 20 tumors, the loss extended in at least one direction beyond the clinically visible tumor, with the extension varying from 4 to 25 mm. Thirty-two of 36 FVL biopsies showed histologic change (including 7 squamous cell carcinoma/carcinomas in situ, 10 severe dysplasias, and 15 mild/moderate dysplasias) compared with 1 of the 66 FV retained (FVR) biopsies. Molecular analysis on margins with low-grade or no dysplasia showed a significant association of LOH in FVL biopsies, with LOH at 3p and/or 9p (previously associated with local tumor recurrence) present in 12 of 19 FVL biopsies compared with 3 of 13 FVR biopsies (P=0.04). CONCLUSIONS: These data have, for the first time, shown that direct FV can identify subclinical high-risk fields with cancerous and precancerous changes in the operating room setting.

Adult↗

The development, implementation, utilization and outcomes of a comprehensive dental program for older adults residing in long-term care facilities.

This paper documents the experience of the University of British Columbia's Geriatric Dentistry Program (GDP) with emphasis on the dental treatment needs of patients during its first year of operation. The GDP provided access to dental care for residents of longterm care facilities, education for hospital staff concerning daily mouth care, education of dental students and an opportunity for research. The first year of clinical activity saw a small, yet significant, improvement in oral health for residents using the dental services. We hope that the outcomes of this new dental program for long-term care facilities will encourage dentists to provide care for this vulnerable population.

Aged↗

Oral disorders in institution-dwelling elderly adults: a graphic representation.

This study was conducted to assess the oral health status and dental care needs of elderly adults living in long-term care facilities. Dentists examined 601 elderly adults, living in one of six extended-or intermediate-care facilities, between September 1999 and May 2000. Data from 532 of the subjects were analyzed with descriptive statistics and zero-order inverse polynomials. Using a computer program, the authors compiled summaries of oral health data on individuals and institutional levels. This study suggests that there are numerous unmet dental needs among elderly adults who live in institutions. The CODE index used to assess the oral health of these residents offers a systematic portrayal of oral disorders in terms of severity. As the authors demonstrated, this index can be readily analyzed using zero-order inverse polynomials to summarize collected data into a graphic description, which can be helpful in managing and administrating oral health care interventions in long-term care facilities.

Age Factors↗

Oral disorders and chronic systemic diseases in very old adults living in institutions.

This study evaluated whether oral disorders were associated with chronic systemic diseases in 532 Canadian adults who are old and very old and living in institutions. A brief oral examination documented tooth retention, caries, and periodontal and gingival health. Medical records provided information about chronic systemic conditions. A history of stroke was associated with a higher experience of caries, a higher ratio of decayed-to-present teeth, and more gingival and periodontal problems. Participants with high blood pressure, osteoporosis, or diabetes were more likely to be edentulous or to have fewer teeth than participants who did not have these conditions. Participants who had arthritis retained more teeth with age. Participants who had more diseases also tended to have poorer gingival or periodontal conditions, fewer teeth, and higher risk of edentulousness. The associations between systemic diseases and more severe oral disorders may be direct or may be mediated by underlying factors such as health behaviors.

Age Factors↗

Simple device for the direct visualization of oral-cavity tissue fluorescence.

Early identification of high-risk disease could greatly reduce both mortality and morbidity due to oral cancer. We describe a simple handheld device that facilitates the direct visualization of oral-cavity fluorescence for the detection of high-risk precancerous and early cancerous lesions. Blue excitation light (400 to 460 nm) is employed to excite green-red fluorescence from fluorophores in the oral tissues. Tissue fluorescence is viewed directly along an optical axis collinear with the axis of excitation to reduce inter- and intraoperator variability. This robust, field-of-view device enables the direct visualization of fluorescence in the context of surrounding normal tissue. Results from a pilot study of 44 patients are presented. Using histology as the gold standard, the device achieves a sensitivity of 98% and specificity of 100% when discriminating normal mucosa from severe dysplasia/carcinoma in situ (CIS) or invasive carcinoma. We envisage this device as a suitable adjunct for oral cancer screening, biopsy guidance, and margin delineation.

Carcinoma, Squamous Cell↗