OBJECT: Examination of blood perfusion in the masseter muscle in the course of repetitive isometric contraction by arterial spin-labeling (ASL) MR imaging and additional T2 relaxation time measurements during and after masseter muscle activation. MATERIALS AND METHODS: Anatomical and ASL imaging was performed (3 T) in the masseter muscle of seven healthy volunteers before and after sustained clenching (30s) at maximum voluntary contraction (MVC). Several cycles of clenching were repeated in an overall period of 11 min. ASL imaging was performed by an adapted FAIR-TrueFISP technique. Time to peak and time to baseline were systematically analyzed in recorded perfusion curves. T2 relaxation times were estimated using a multi-echo spin-echo sequence. The influence of MVC on T2 was statistically analyzed. RESULTS: In all cases, perfusion imaging and assessment of T2 relaxation time was feasible. Mean perfusion values at rest calculated from all volunteers were 97.9 ± 17.1 ml/min/100 g (right masseter) and 83.0 ± 18.1 ml/min/100 g (left masseter). The percentage mean perfusion increase in all volunteers immediately after clenching ranged between 114 and 154%. Mean time to peak was 13.7 s (range: 8.0-26.7 s; SD 5.6 s), and mean time to baseline was 25.6 s (range: 18.7-37.0 s; SD 5.4 s). No significant influence of MVC on T2 relaxation time was found, although a tendency to T2 increase after each clenching stress was observed. CONCLUSION: Clear contraction-related perfusion changes of the masseter muscle could be assessed in high spatial and temporal resolution by means of ASL. In contrast, no significant T2 changes were measured. ASL imaging could serve as supplementing tool for studying masticatory function and dysfunction.
OBJECT: Examination of blood perfusion in the masseter muscle in the course of repetitive isometric contraction by arterial spin-labeling (ASL) MR imaging and additional T2 relaxation time measurements during and after masseter muscle activation. MATERIALS AND METHODS: Anatomical and ASL imaging was performed (3 T) in the masseter muscle of seven healthy volunteers before and after sustained clenching (30s) at maximum voluntary contraction (MVC). Several cycles of clenching were repeated in an overall period of 11 min. ASL imaging was performed by an adapted FAIR-TrueFISP technique. Time to peak and time to baseline were systematically analyzed in recorded perfusion curves. T2 relaxation times were estimated using a multi-echo spin-echo sequence. The influence of MVC on T2 was statistically analyzed. RESULTS: In all cases, perfusion imaging and assessment of T2 relaxation time was feasible. Mean perfusion values at rest calculated from all volunteers were 97.9 ± 17.1 ml/min/100 g (right masseter) and 83.0 ± 18.1 ml/min/100 g (left masseter). The percentage mean perfusion increase in all volunteers immediately after clenching ranged between 114 and 154%. Mean time to peak was 13.7 s (range: 8.0-26.7 s; SD 5.6 s), and mean time to baseline was 25.6 s (range: 18.7-37.0 s; SD 5.4 s). No significant influence of MVC on T2 relaxation time was found, although a tendency to T2 increase after each clenching stress was observed. CONCLUSION: Clear contraction-related perfusion changes of the masseter muscle could be assessed in high spatial and temporal resolution by means of ASL. In contrast, no significant T2 changes were measured. ASL imaging could serve as supplementing tool for studying masticatory function and dysfunction.
Authors: J M F Varela; N B Castro; B M Biedma; J L Da Silva Domínguez; J S Quintanilla; F M Muñoz; U S Penín; J G Bahillo Journal: J Oral Rehabil Date: 2003-10 Impact factor: 3.837
Authors: Brigitte Ohlmann; Peter Rammelsberg; Volkmar Henschel; Bodo Kress; Olaf Gabbert; Mark Schmitter Journal: Int J Prosthodont Date: 2006 Jul-Aug Impact factor: 1.681
Authors: M Banci; E Rinaldi; M Ierardi; N S Tiberio; G L Boccabella; C Barbieri; F Scopinaro; S Morelli; M DeSantis Journal: Angiology Date: 1998-08 Impact factor: 3.619
Authors: Jihan Harki; Mustafa Suker; M Sherezade Tovar-Doncel; Louisa Jd van Dijk; Désirée van Noord; Casper Hj van Eijck; Marco J Bruno; Ernst J Kuipers; Can Ince Journal: Clin Exp Gastroenterol Date: 2018-10-18