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Objective: To characterise the activation of the contra- and ipsilateral primary somatosensory cortex (SI) after tactile stimulation of the face., Methods: Trigeminal somatosensory evoked magnetic fields (TSEFs) were recorded after tactile stimulation of the lower lip, cheek, chin and forehead in 11 healthy subjects. The responses were determined visually from the waveforms and modelled with equivalent current dipoles (ECDs)., Results: Contralateral SI responses were evoked in all subjects after lip stimulation, and in 91% and 64% after right and left cheek, 73% and 82% after chin and 64% and 27% after forehead stimulation. The responses usually showed an early double-peak wave pattern, the underlying sources localising to the SI. In addition, altogether 37 ipsilateral SI responses were evoked in eight subjects. Fourteen of these responses were amenable to ECD modelling and localised to ipsilateral SI., Conclusions: Tactile stimulation of the lip area reliably activates the contralateral SI in normal subjects, but the success rate for other trigeminal areas is lower. Ipsilateral responses can be present after stimulation of any of the trigeminal branches in normal subjects., Significance: Recording of TSEFs after tactile stimulation of particularly the lip area provides a non-invasive technique to study the function of the trigeminal nerve.

Articulatory proficiency of /r/ and /s/ sounds, voice quality and resonance, speech intelligibility, and intraoral sensation were examined prospectively before operation, and at four time points during a 1-year follow-up after microvascular transfer. Forty-one patients with a large oral or oropharyngeal carcinoma undergoing tumor resection and free-flap reconstruction usually combined with radiotherapy participated in the study. Articulation, voice, and resonance were investigated both live and from recorded speech samples by two trained linguistic examiners. The patients completed a self-rating of their speech intelligibility and were assessed for anterior intraoral surface sensation by means of 2-point moving discrimination. Misarticulations of /r/ and /s/ increased significantly after the therapy. Voice quality and resonance remained essentially normal. Speech intelligibility deteriorated significantly. Intraoral sensation decreased postoperatively but was not related to speech outcome. Sensate flaps did not prove to be superior in relation to speech tasks. A multidisciplinary approach is advocated in assessment of speech outcome after cancer surgery. Speech therapy is strongly recommended, even in the absence of a gross articulatory handicap.

Swallowing and intraoral sensation outcome were investigated prospectively after microvascular free-flap reconstruction. Forty-one patients with a large oral or oropharyngeal carcinoma underwent free-flap surgery usually combined with radiotherapy. The patients completed modified barium swallow, self-rating of swallowing, and 2-point moving discrimination preoperatively and at four time points during the 12-month follow-up period, and a plain chest X-ray one year after operation. Swallowing was impaired with respect to an objective and subjective measure after therapy. Rates for nonsilent and silent aspiration increased during the follow-up. Intraoral sensation deteriorated. Swallowing outcome was not related to sensation. One year after surgery, 86% of the patients ate regular masticated or soft food. Microvascular transfers offer a reasonable option for oral reconstruction. This study does not support the need for sensate flaps. Swallowing problems should be routinely sought and patients rehabilitated during a sufficiently long follow-up with videofluorography regardless of the patient's perception of swallowing.