Sonographic evaluation of diaphragmatic function during breathing control.

OBJECTIVE: To investigate the effect of "breathing control" on sonographic diaphragmatic excursion. METHOD: A prospective, randomized, assessor-blinded study design involving 20 physiotherapy students; ten with knowledge of the breathing control technique (Group BC) and ten without (Group CON). All participants were asked to perform a Chester step test. Group BC performed BC, while Group CON adopted their own breathing pattern during recovery after the step test. Respiratory rate and sonographic parameters of the diaphragm including diaphragmatic excursion, speed of diaphragmatic contraction (slope of contraction), and inspiratory time were recorded before and after the step test. RESULTS: All baseline data were similar for both groups except age. Respiratory rate at 1 min post-step test was higher in Group CON (24.6±4.9 bpm) compared to Group BC (15.6 ± 3.8 bpm) (p < 0.001). Post-step test sonographic evaluation demonstrated an increase in diaphragmatic excursion with a significant time and group interaction (F(4,72) = 5.499, p = 0.005). Post hoc analysis revealed that the diaphragmatic excursion was significantly higher in Group BC compared to Group CON at first, second and third minute post-step test. Time and group interactions were not significant in inspiration time (F(4,72) = 2.459, p = 0.082) nor the slope of contraction (F(4,72) = 0.655, p = 0.582)]. CONCLUSION: Post-exercise diaphragmatic excursion was higher in participants applying BC. Non-invasive ultrasonography is able to promote objective evaluation of the relationship between breathing techniques and diaphragmatic function.

Assessment of post-radiotherapy salivary glands.

Salivary glands are usually irradiated during radiotherapy for head and neck cancers, which can lead to radiation-induced damage. Radiation-induced xerostomia (oral dryness) is the most common post-radiotherapy complication for head and neck cancer patients and can reduce the patient's quality of life. Accurate and efficient salivary gland assessment methods provide a better understanding of the cause and degree of xerostomia, and may help in patient management. At present, there are different methods for the assessment of salivary gland hypofunction; however, none of them are considered to be standard procedure. This article reviews the value of common methods in the assessment of post-radiotherapy salivary glands.

Evaluation of radiation-induced changes to parotid glands following conventional radiotherapy in patients with nasopharygneal carcinoma.

OBJECTIVES: Xerostomia is a common post-radiotherapy (post-RT) complication in nasopharyngeal carcinoma (NPC) patients. This study evaluated the relation of post-RT parotid gland changes with the dose received. METHODS: Data from 18 NPC patients treated by radiotherapy between 1997 and 2001 were collected. Parotid gland volumes were measured and compared between their pre-RT and post-RT CT images; both sets of CT were conducted with the same scanning protocol. Doppler ultrasound was used to assess the haemodynamic condition of the glands after radiotherapy. Doppler ultrasound results were compared against 18 age-matched normal participants. A questionnaire was used to evaluate the patients' comments of xerostomia condition. Radiotherapy treatment plans of the participants were retrieved from the Eclipse treatment planning system from which the radiation doses delivered to the parotid glands were estimated. The correlations of parotid gland doses and the post-RT changes were evaluated. RESULTS: The post-RT parotid glands were significantly smaller (p<0.001) than the pre-RT ones. They also demonstrated lower vascular velocity, resistive and pulsatility indices (p<0.05) than normal participants. The degree of volume shrinkage and subjective severity of xerostomia demonstrated dose dependence, but such dependence was not definite in the haemodynamic changes. CONCLUSION: It was possible to predict the gland volume change and subjective severity of xerostomia based on the dose to the parotid glands for NPC patients. However, such prediction was not effective for the vascular changes. The damage to the gland was long lasting and had significant effects on the patients' quality of life.