Electroglottogram approximate entropy: a novel single parameter for objective voice assessment.

BACKGROUND: The electroglottogram approximate entropy value is a numerical variable which gives an overall measure of voice quality. It is derived by analysing the complexity of the electroglottogram waveform using regulatory statistics. AIMS: (1) To use electroglottogram approximate entropy to measure voice quality in patients with glottic pathology and in normal subjects, to ascertain whether this parameter can distinguish between pathological and normal voices. (2) To ascertain whether electroglottogram approximate entropy can measure voice change over time within individual subjects. (3) To determine any correlation between electroglottogram approximate entropy and the grade-roughness-breathiness-asthenia-strain scale. METHODS: One hundred and forty-one normal volunteers were recruited to characterise electroglottogram approximate entropy in the normal voice. One hundred and eighty-six patients with glottic squamous cell carcinoma underwent electroglottogram approximate entropy measurement prior to radiotherapy and then three to six months and one year after treatment. Subjects' voices were categorised by a speech therapist using the grade-roughness-breathiness-asthenia-strain scale. RESULTS: The mean electroglottogram approximate entropy of the normal volunteers was 0.302 (range 0.05-0.42). The mean electroglottogram approximate entropy of the glottic squamous cell carcinoma patients was significantly lower prior to treatment, at 0.227 (range 0.001-0.397; p < 0.0005), but improved after radiotherapy to 0.277 at three to six months and 0.282 at one year. Electroglottogram approximate entropy results correlated significantly with grade-roughness-breathiness-asthenia-strain scale results. CONCLUSION: Electroglottogram approximate entropy can be used to assess change in voice quality resulting from glottic morphological abnormality. Electroglottogram approximate entropy values improve as voice quality improves after treatment. Electroglottogram approximate entropy values correlate significantly with grade-roughness-breathiness-asthenia-strain scale results.

An assessment of clinically optimal gold marker length and diameter for pelvic radiotherapy verification using an amorphous silicon flat panel electronic portal imaging device.

Verification of target organ position is essential for the accurate delivery of conformal radiotherapy. Megavoltage electronic portal imaging with flat panel amorphous silicon detectors delivers high quality images that can be used for verification of bony landmark position. Gold markers implanted into the target organ can be visualized and used as a surrogate of actual organ position. On-line compensation for marker displacement, by adjusting patient position, can reduce geometric errors associated with radiation delivery. This study assesses the optimal marker length and diameter to be used with an amorphous silicon (a-Si) flat panel detector and electronic portal images (EPIs), prior to implementation of a clinical programme of gold marker insertion in prostate cancer patients. Seven marker sizes varying from 3 mm to 8 mm in length and 0.8 mm to 1.1 mm in diameter were investigated in a group of patients undergoing pelvic radiotherapy using an 8 MV Elekta SL20 linear accelerator. Markers were placed on the skin entry and exit sites of the treatment beam and EPIs in both lateral and anterior pelvic views were acquired. Three observers independently assessed visibility success and failure using a subjective scoring system. Markers less than 5 mm in length or 0.9 mm in diameter were poorly visualized (<70% visualization success in lateral EPIs). The marker measuring 0.9 mm x 5 mm appears to be clinically optimal in pelvic radiotherapy patients (80% visualization success in lateral EPIs) and will be used for actual organ implantation.

Evaluation of the LENT-SOMA scales for the prospective assessment of treatment morbidity in cervical carcinoma.

PURPOSE: To examine the Late Effects Normal Tissue Task Force (LENT)-Subjective, Objective, Management, Analytic (SOMA) scales prospectively in carcinoma of the cervix treated curatively with radiotherapy (RT) using interviews and postal questionnaires and to test the sensitivity of the scales in assessing the radiation effects. METHODS AND MATERIALS: A consecutive series of 100 patients completed questionnaires to score the subjective part of the published LENT-SOMA scales. Assessments were made before RT and at approximately 21, 70, 200, 400, 600, and 800 days after the start of treatment. The acceptability and feasibility of using the scales was examined using compliance in completion of the questionnaires. The scales were validated by evaluating the concordance of data obtained by two independent scorers and by examining the ability of the scales to measure radiation-related symptoms. RESULTS: Questionnaires were completed for 89 patients before RT. The level of noncompliance was 11%. The concordance between scores when two people completed the questionnaires independently was excellent. Subjective subsite scores were highest 21 days after treatment but generally fell by 70 days. The average baseline overall LENT-SOMA subjective scores increased with advancing stage (p = 0.008) and were higher for patients treated with RT alone (p = 0.044). CONCLUSION: In cervical carcinoma, the LENT-SOMA scales were acceptable and feasible to administer in the clinic and appropriate in the measurement of early subjective morbidity from RT.

Tumour size as a prognostic factor in carcinoma of the cervix: assessment by transrectal ultrasound.

Transrectal ultrasound (TRUS) was used to measure tumour size in patients with carcinoma of the cervix and to assess its prognostic significance. Clinical staging was conducted and at the time of examination under anaesthesia, TRUS was used to assess maximum transverse diameter of the tumour. Eighty-one patients were studied. FIGO stages were 1B 34 patients, IIA seven patients, IIB 31 patients, IIIA two patients and IIIB seven patients. Mean tumour diameters by stage were IB 37 mm, IIA 37 mm, IIB 49 mm, IIIA 42 mm and IIIB 50 mm. There was a significant correlation between size and stage (p = 0.001). With a median follow-up of 18 months, 16 relapses have occurred. The actuarial relapse rates at median follow-up by stage were IB 10%, IIA 17%, IIB 22%, IIIA 0% and IIIB 35%. The actuarial relapse rates by size grouping at median follow-up were less than 30 mm 0%, greater than 30 and less than 40 mm 11%, greater than 40 and less than 50 mm 22%, and greater than 50 mm 38%. There was a significant difference between the mean recorded size of the tumours in the relapsed group and the relapse-free group (p = 0.02). Despite the small number of patients and short follow-up, tumour size as measured by TRUS appears to predict relapse.