Geometrical Facial Deformation According to Posture and Non-invasive Ventilation Mask Virtual Fit in Amyotrophic Lateral Sclerosis
Conditions: Amyotrophic Lateral Sclerosis
Sponsor: Pusan National University Yangsan Hospital

2022-05-01 
 
NCT04798183 
Geometrical Facial Deformation According to Posture and Non-invasive 
Ventilation Mask Virtual Fit in Amyotrophic Lateral Sclerosis 
 
Background  
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that eventually affects 
the respiratory muscles. In most cases of the slow progression of respiratory failure, noninvasive 
ventilation (NIV) is the first treatment option. NIV treatment provides a better quality of life and is, 
therefore, strongly recommended; however, its use must consider the type of ALS. Severe bulbar 
dysfunction limits NIV treatment. Aside from additional NIV options in ALS, including mouthpiece 
ventilation and intermittent abdominal pressure ventilation, prolonged use of a ready-made face mask 
is impractical for several reasons. Cognitive impairments can affect the maintenance of NIV. 
Hypersalivation and bronchial secretion disrupting ventilation can lead to poor NIV adherence. Pressure 
injuries are another clinical issue. The incidence of pressure injuries associated with NIV masks ranges 
from 10–31%. Long-term use of NIV face masks can result in pressure injuries at the contact area, and 
skin-protective patches may not prevent skin problems. Patients with bulbar ALS frequently have 
postural facial deformations, and these can lead to difficulties in wearing the NIV mask. No previous 
study has analyzed morphological differences in facial soft tissue according to posture in ALS. 
 
Objective  
The aim of this study was to compare the deformations of the face in different postures in subjects with 
bulbar ALS and healthy participants. This study also virtually fitted an NIV mask to understand how 
the NIV mask interface affects the face in different postures. 
 
Methods 
Participants 
 
Amyotrophic lateral sclerosis with bulbar 
involvement patients 
Healthy participants 
Inclusion 
criteria 
• 
a patient with Amyotrophic Lateral 
Sclerosis, 16-60 years old 
• 
a patient with respiratory difficulty 
• 
a patient who requires or anticipates 
mechanical ventilation 
• 
a volunteer without history of facial 
surgery or neuromuscular disease, 16-60 
years old 
• 
a volunteer without respiratory difficulty 

2022-05-01 
 
NCT04798183 
• 
a patient who visit out- or inpatient clinic 
at rehabilitation hospital 
Exclusion 
criteria 
• 
a patient who cannot scan due to 
respiratory instability 
• 
a patient who cannot bear posture for 3D 
scanning 
• 
a volunteer with neuromuscular disease 
• 
a volunteer with history of facial surgery 
or palsy 
 
Interventions 
The face is scanned with 5-camera unit 3D scanning system (3dMD, Atlanta, Georgia) in the sitting, 
supine, and lateral decubitus positions. Ten anatomical landmarks are located in the nasal root area for 
4 points (sellion, glabella, left dacryon, and right dacryon) and in the oral area for 6 points (subnasale, 
SN; labial superius, LS; labial inferius, LI; cheilion left, CL; cheilion right, CR; and promentale, PM) 
where major skin deformations occur. Each subject should keep their mouth closed naturally during 
scanning. The amounts of change of a landmark position in the anteroposterior or lateral direction 
according to the posture change (from sitting to supine; from sitting to lateral decubitus) are measured. 
 
Outcome measurements and statistical analysis 
Primary outcome measure: The change in position of anatomical landmarks 
Change is reported as the mean displacement (mm) during the change in position from the initial 
position (sitting) to the subsequent position (supine & side-lying). The extent of facial landmark changes 
in different postures indicative of facial deformation in healthy subjects and subjects with bulbar ALS 
will be compared. A repeated-measures analysis of variance will be performed at a ¼ 0.05 to assess the 
effectiveness of the group and posture. The Tukey-Kramer method will be used as a post hoc analysis 
for multiple comparisons of means at a ¼ 0.05. All analyses will be performed using Minitab v.19 
(Minitab, State College, Pennsylvania).