Study and type | Objectives | Participants | Methods | Main outcomes |
---|---|---|---|---|
Loimu et al. [9], prospective | Use of DWI for assessment of post-IMRT salivary gland function at rest and during stimulation Matching ADC changes with salivary gland radiation dose, correlating to salivary gland function on scintigraphy | 20 patients with HNSCC Treatment: Bilateral neck IMRT with concurrent cisplatin chemotherapy | MRI scanning at a mean 8 days prior to treatment commencement and mean 6 months after completion Post-treatment: DWI series acquired at rest and with ascorbic acid oral stimulation Salivary scintigraphy scanning at mean 3 days prior to treatment onset and mean 6 months after completion. Calculation of salivary ejection fraction | Significant increase in ADC values post-RT in both parotid and submandibular glands (p < 0.001) Significantly higher maximum ADC after stimulation in post-RT vs pre-RT (p < 0.001) Linear correlation between salivary gland RT dose and pre- to post-RT ADC change |
Zhang et al. [45], prospective | Use of DWI to assess post-RT salivary gland function during rest and stimulation Follow-up of radiation-induced xerostomia | 23 patients with NPC Treatment: IMRT with concurrent docetaxel, cisplatin and 5-fluorouracil chemotherapy | MRI scanning pre-RT, 1 week and 1 year post-RT completion Post-RT: DWI sequences acquired at rest and with ascorbic acid oral stimulation Clinical xerostomia assessment done at the same time as MRI scanning | Significant increase in 1 week post-RT parotid gland ADC at rest and max ADC at stimulation compared to pre-RT (p < 0.001), followed by decrease at 1 year post-RT but still higher than baseline (p < 0.001) Significant increase in 1 week post-RT submandibular gland ADC at rest compared to pre-RT (p < 0.001). No decrease at 1 year post-RT 4 significant predictors for improvement of xerostomia: dose to parotid glands, submandibular ADC at rest, max parotid ADC at stimulation, and time to max parotid ADC during stimulation at 1 week post-RT |
Fan et al. [59], prospective | Use of DWI to assess salivary gland function during post-RT follow-up | 31 patients with NPC Treatment: Induction chemotherapy followed by helical tomotherapy RT with concurrent docetaxel or cisplatin | MRI scanning at timepoints 2–3 weeks pre-RT and 1, 3, 6, 9 and 12 months post-RT Salivary flow rate and xerostomia assessment conducted with each MRI scan | Significantly higher ADC for parotid and submandibular glands at all post-RT timepoints compared to pre-RT (p < 0.01) Reduced salivary flow rate post-RT, with gradual improvement over time Linear correlation between mean parotid radiation dose and pre- to post-RT change in ADC Significantly higher parotid ADC 1 month and 3 month post-RT in those with mild and moderate xerostomia than those with severe xerostomia (p < 0.05) Positive correlation between salivary gland ADC values post-RT and xerostomia scores post-RT |
Shi et al. [60], prospective | Use of DWI with gustatory stimulation to assess salivary gland function pre- and post-RT Correlation of ADC changes with xerostomia scores | 30 patients with NPC Treatment: IMRT with concurrent platin-based chemotherapy | DW-MRI scanning before and after RT, follow-up of 12–30 months post-RT DWI sequences taken at rest and after lemon juice oral stimulation Salivary flow rate measurements at resting and stimulated states | Significant increase in resting and stimulated ADC for all salivary glands post-RT compared to pre-RT (p = 0.000) Significantly lower resting and stimulated salivary flow rate in all salivary glands post-RT compared to pre-RT (p = 0.000) Positive correlation between parotid gland ADC at rest post-RT and xerostomia scores post-RT |
Zhang et al. [47], prospective | Use of DWI to evaluate early ADC changes in salivary glands during RT Associate mid-RT ADC changes with post-RT xerostomia | 26 patients with NPC Treatment: IMRT | MRI scanning pre-RT and two weeks after RT commencement DWI sequences acquired at rest and during ascorbic acid oral stimulation Xerostomia evaluation 6 months post-RT | Significantly higher resting ADC in salivary glands during RT compared to pre-RT (p < 0.01) Negative correlation between ADC changes from pre- to mid-RT with degree of xerostomia at 6 months post-RT |