Distinctive Cortical Articulatory Representation in Cleft Lip and Palate: A Preliminary Functional Magnetic Resonance Imaging Study

Magnetoencephalographic evaluation of repaired lip sensation in patients with cleft lip

Background

Cleft lip is the most common congenital anomaly worldwide. Nevertheless, lip somatosensory characteristics of patients with cleft lip after cheiloplasty have not yet been determined. The present study used magnetoencephalography to objectively evaluate the lip sensation in patients with unilateral cleft lip to establish a new objective evaluation method.

Methods

Participants were 15 patients with unilateral cleft lip after cheiloplasty (UCL group), and 30 healthy young subjects (control group). Five points of the upper and lower lips were stimulated electrically to measure somatosensory evoked magnetic fields (SEFs). The sources of the magnetic fields were modeled as single equivalent current dipoles (ECDs). ECDs located on the central sulcus by superimposition on magnetic resonance images were analyzed. Latency and intensity at 50–75 ms (cP60m) observed in the UCL group were compared with those in the control group. Thresholds of tactile stimuli in both groups were obtained using Semmes–Weinstein monofilaments for subjective sensory evaluation.

Results

No significant difference was found in the intensity of the cP60m or subjective evaluation between the groups. However, the latency of the cP60m was significantly longer in the upper lip of the UCL group than in the control group.

Conclusions

SEFs showed a difference in lip sensation between the UCL group and the control group, suggesting that longer latency might be caused by the effects of surgical scarring on the neurotransmission pathway. These results suggest SEFs as useful for the objective evaluation of lip sensations. This study might improve future surgical procedures and lip functions of patients with cleft lip.

Temporal characteristics of nasalization in Persian speaker children with and without cleft palate

OBJECTIVES

The purpose of this study was to measure and compare temporal patterns of nasalization in Persian children with and without cleft palate in three vowel contexts.

METHODS

A Sample of 14 children with repaired cleft palates with or without cleft lip with moderate to severe hyper nasality and 14 children without cleft palate was chosen as subjects. The subjects were chosen from the ages of 4 to 12 years. The nasal onset interval, nasal offset interval and total nasalization duration were obtained from acoustic waveforms and spectrograms in three vowel contexts using Praat Software. For eliminating the effect of different speed of speech in the cleft palate group and control group, the ratio of nasalization duration was calculated.

RESULTS

Total nasalization duration are demonstrated by acoustic signals which shows the total significant different temporal patterns in children with cleft palate and without cleft palate and across the vowel contexts (P<0.000).

CONCLUSIONS

Longer nasalization durations in children with cleft palate in comparison to children without cleft palate show the delayed or deviant temporal patterns in children with cleft palate. The duration of nasalization reflecting temporal patterns of the oral-nasal acoustic impedance in children with cleft palate may have an influence on the perception of hyper nasality.

Functional neuroanatomy of lexical processing in children with cleft lip and palate

BACKGROUND

Patients with palatal clefts are predisposed to developing speech and language abnormalities. Emerging evidence indicates that children with cleft lip and/or cleft palate have higher rates of learning disabilities than the general population and differences in brain morphology.

METHODS

Magnetic resonance imaging of 12 individuals with isolated unilateral complete clefts of the lip and palate produced functional images during three lexical processing tasks: generation of verbs, opposites, and rhymes. Direct statistical comparisons were made between subjects with cleft lip and palate and controls (matched for age and performance) from an extant data set, both as a group and individually.

RESULTS

Two types of differences were found. Compared with unaffected controls, subjects with clefts showed a delayed and elongated blood oxygen level-dependent response in regions found throughout the cerebrum, including in the prefrontal cortex, cingulate gyrus, right precuneus, and right temporal gyrus. A right middle frontal gyrus region was activated by these tasks in controls but not in subjects with clefts. Developmental analysis showed that subjects 14.5 years and older (n = 5) had a larger number of age-related regions differing in blood oxygen level-dependent response from controls than did younger subjects (n = 7). Single-patient analysis demonstrated substantial individual variability.

CONCLUSIONS

Children with cleft lip and palate, performing lexical processing tasks at a comparable level of proficiency, use a similar but nonidentical functional neuroanatomy than peers without clefts. Differing neural circuitry for language tasks and differing developmental trajectories could help explain the predisposition to velopharyngeal dysfunction and learning disabilities in this population.

Combined fMRI and MRI movie in the evaluation of articulation in subjects with and without cleft lip and palate

OBJECTIVE

This study was undertaken to explore the application of functional magnetic resonance imaging (fMRI) and MRI movies in the evaluation of articulatory function in subjects with and without cleft lip and palate (CLP).

DESIGN

The authors examined brain activation and the dynamic movement of articulators during bilabial and velar plosives using fMRI and MRI movies.

SUBJECTS

Two subjects, one with unilateral cleft lip and palate (UCLP) and one with bilateral cleft lip and palate (BCLP), and 12 non-CLP volunteers.

RESULTS

Activation foci were found in the precentral gyrus, thalamus, and cerebellum in non-CLP volunteers. In comparison, similar regions were activated in the UCLP subject during both plosives, whereas the regions activated in the BCLP subject were different, particularly during the velar plosive. The dynamic movement of articulators in the UCLP subject was comparable to that in a non-CLP volunteer but different from that in the BCLP subject.

CONCLUSIONS

The results suggest that these two MRI modalities may be a promising evaluation methodology for articulatory function in CLP from central and peripheral perspectives.