[Abstract]
Objective: To investigate the clinical characteristics of infant
congenital tongue base cysts.
Methods: This retrospective study involved 37 infants with congenital
tongue base cysts in our hospital.
Results: The median age at admission was 95 (15-360) d for these babies.
The main clinical manifestations were laryngeal stridor (33/37 89.2%),
dyspnea (8/37 21.6%), inspiratory trisomy (6/37 16.2%), and choking
and vomiting milk (14/37 37.8%). Eight cases (21.6%) were misdiagnosed
as laryngomalacia in another hospital, while 4 cases (10.8%) were
misdiagnosed as pneumonia. One case required emergency intubation for
rescue due to dyspnea before surgery. The root of the tongue was found
to occupy space during intubation. Six cases (16.2%) had cysts found
through CT examination. Three cases (8%) had cysts found during
bronchoscopy due to pneumonia. The remaining cysts were found in the
root of the tongue through laryngoscopy. Laryngoscopy was performed in
all children before the operation, and CT examination in 28 patients
before the operation showed that the median diameter of the cyst was 10
mm (5-20 mm), All children underwent radiofrequency ablation of glossal
root cysts through laryngoscopy. Eight patients were transferred to the
intensive care unit (ICU) for treatment post-operatively. The median
intubation time was 4.5 days (2-5 days).
Conclusion: Infancy congenital tongue base cysts have an early onset and
atypical clinical manifestations. Electronic laryngoscopy combined with
neck CT should be performed promptly in patients with laryngeal stridor
and feeding difficulty to facilitate accurate diagnosis, and timely
surgery is needed.
Succinct key points:
1、Congenital tongue base cyst in infants is located at the bottom of
the tongue root, with a low incidence.
2、This retrospective study involved 37 infants with congenital tongue
base cysts in our hospital.
3、Infancy congenital tongue base cysts have an early onset and atypical
clinical manifestations.
4、Electronic laryngoscopy combined with neck CT should be performed
promptly in patients with laryngeal stridor and feeding difficulty.
5、It is vital for these patients to be diagnosed and treated as soon as
possible.
Key words: Airway obstruction; infant; thyroglossal cyst; laryngoscopy
Congenital tongue base cyst in infants is located at the bottom of the
tongue root, with a low incidence, which can cause respiratory and
swallowing disorders[1]. The clinical manifestations of congenital
tongue root cysts are similar to those of congenital laryngeal
chondromalacia and congenital laryngeal web, which are easily
misdiagnosed. This paper analyzes the clinical characteristics of 37
cases of congenital tongue root cysts diagnosed and treated in our
hospital.
Methods:
This study is a retrospective study. From January 2014 to January 2022,
37 cases of congenital tongue base cysts confirmed by surgery and
pathology in the Department of Otolaryngology of“Blinded for review”
were included in this study for analysis.
The diagnosis mainly depends on the patient’s medical history, physical
examination and auxiliary examination, as follows: (1) The age of onset
and visit ranged from 0-1 years old. (2) Main symptoms and signs:
laryngeal stridor and feeding difficulty were found at admission.
Inspiratory trisomy was found on physical examination. (3) Auxiliary
examination: neck CT showed round or oval cysts at the root of the
tongue, clearly demarcated from the surrounding tissues, with regular
contours. Electronic laryngoscopy revealed a hemispherical gray-white
cystic neoplasm at the root of the tongue, with a smooth surface,
squeezing the epiglottis and blocking the upper airway. (4) Pathological
examination after the operation mainly showed squamous epithelium,
interstitial edema and congestion. Combined with the history, signs,
auxiliary examinations and pathological results, congenital cysts of the
root of the tongue can be diagnosed. We retrospectively analyzed the
children’s sex, symptom onset time, visit time, main manifestations,
complications such as pneumonia and laryngomalacia, intubation before
and after surgery, admission to the ICU, neck CT, treatment and
postoperative outcomes.
The patients were followed up 6 months to 7 years, with an average of
56.6 months.
The descriptive analysis method was adopted. Count data are expressed as
the number of cases and percentage. Measurement data with a normal
distribution are expressed as ±s, and measurement data with a nonnormal
distribution are expressed as the median (min-max).
The clinical protocol used for these cases was established according to
the ethical guidelines of the Helsinki Declaration and was approved by
the Human Ethics Committee of “Blinded for review”.
Ethical considerations
This study was approved by the Institutional Ethics and Research
Committee of Our hospital
Results:
Among the 37 children with congenital tongue base cysts, 23 were male,
14 were female, 17 were born via cesarean section, and 20 were
spontaneous deliveries. All of them were full-term infants, with a birth
weight of 3331.6 ± 389.87 g.
The median admission age of the 37 children was 95 days (15-360 days).
Twenty-six (70.3%) children had laryngeal stridor and inspiratory
dyspnea after birth. Two (5%) patients were less than one month old.
Eight (21.6%) patients were misdiagnosed with laryngomalacia in other
hospitals, and 4 (10.8%) patients were misdiagnosed with pneumonia in
other hospitals. One patient required emergency intubation for rescue
because of dyspnea before the operation. The root of the tongue was
found to occupy space during intubation, and 6 (16.2%) patients were
found to have cysts of the root of the tongue through CT examination.
Three cases (8%) were found to have tongue root cysts by bronchoscopy
due to pneumonia, and the rest were found to have tongue root cysts by
laryngoscopy.
A total of 33 cases (89.2%) had laryngeal stridor, 8 cases (21.6%) had
dyspnea, 6 cases (16.2%) had inspiratory trisomy, 14 cases (37.8%) had
cough and vomiting, 14 cases (37.8%) had cough and stridor at the same
time, 13 cases (35.1%) had pneumonia, 10 cases (27.1%) had
laryngomalacia, and 9 cases (24.3%) had pneumonia and laryngomalacia at
the same time when they came to our hospital.
All children were examined with electronic laryngoscopy (Figure 1-A), 28
patients were examined with neck CT (Figure 1-B), and the median tumor
diameter was 10 mm (5-20 mm).
All children received radiofrequency surgery with a self-retaining
laryngoscope. During the operation, the cyst was completely removed, and
hyoid contouring was performed during the surgery. Eight patients were
intubated and transferred to the ICU for treatment after the operation.
The median intubation time was 4.5 days (2-5 days). The examination of
the laryngoscope after the operation indicated that the white wound
membrane was well formed. Histological examination confirmed the
diagnosis of a congenital tongue base cyst (Figure 1-C). There was no
recurrence after 6 months of follow-up (Figure 1-D).
Discussion:
Congenital tongue base cysts usually occur on the midline between the
back of the tongue and the lingual foramen cecum. Most cysts are mucous
retention cysts[2]. They are generally deep and covered with a thick
layer of mucous membrane. Inside the cyst is serous liquid, and it is
usually near and oppresses the epiglottis, which may lead to respiratory
obstruction and feeding difficulty. The cysts originate from the
endoderm and mesoderm of the embryonic stage. Because of the lack of
specificity in clinical manifestations, they are easily misdiagnosed as
congenital laryngomalacia and neonatal pneumonia. As a result, children
cannot receive timely and effective treatment, resulting in serious
consequences. It has been reported in the literature that 50% of
congenital tongue base cysts are definitively diagnosed after
autopsy[3], indicating that the rates of missed diagnosis and
misdiagnosis of this disease are high.
This study shows that 26 children (70.3%) suffered from laryngeal
wheezing, dyspnea and feeding difficulties after birth, which indicates
that the clinical symptoms in these children occur early. The common
clinical manifestations of this disease are laryngeal wheezing,
inspiratory dyspnea, choking, and vomiting. These clinical
manifestations lack specificity, so it is impossible to make a diagnosis
based on these clinical manifestations. The diagnosis must be made
through auxiliary examination. Because congenital tongue base cysts grow
expansively, squeezing the epiglottis, they may cause dyspnea and
dysphagia.
This study shows that electronic laryngoscopy has a high detection rate
for congenital tongue base cysts and is the first choice for such
children[4]. Electronic laryngoscopy has good flexibility and a wide
field of vision and can more clearly demonstrate the scope and
characteristics of the lesions. Electronic laryngoscopy also causes less
stimulation for children and can detect and diagnose laryngeal diseases
earlier, but it also has certain limitations. For example, the size and
scope of the tumor cannot be accurately measured, and the anatomical
relationship with the surrounding tissues cannot be determined. CT
scanning can accurately display the anatomical location of the cyst and
the relationship between the cyst and the hyoid bone. It is the most
commonly used imaging examination method for diagnosing congenital
tongue base cysts. MR examination is not recommended for this disease.
Because MR examination takes a long time, it is not suitable for
children with serious illness. In addition, MR examination requires
sedatives, which may increase the risk of upper airway obstruction.
Thyroid cartilage has not been ossified in the neonatal period.
Ultrasound has good sound transmission and can show the throat and
related areas well. It can identify the location, boundary, shape, blood
flow and other conditions of the lesions. It can identify cystic and
solid properties and can exclude ectopic thyroid glands, hemangioma and
other related diseases. Ultrasound also has the advantages of high
safety, convenient inspection, no radioactivity, and no need for
sedation and can be used as an important modality for screening
congenital tongue base cysts[5]. However, the results of ultrasonic
examination are often affected by the experience of the examiner and the
performance of the machine, which may affect the detection rate.
Therefore, electronic laryngoscopy, neck ultrasound and neck CT should
be combined to make a correct diagnosis, to improve the diagnostic
accuracy of congenital tongue base cysts and to reduce the incidence of
missed diagnosis or misdiagnosis.
For children with congenital tongue base cysts, surgery should be
carried out as soon as possible to remove the occupation and relieve the
obstruction. The surgery should remove as much of the cyst wall as
possible and contour the hyoid bone to reduce postoperative recurrence.
When the child has obvious dyspnea, aspiration of the cysts can
temporarily relieve the symptoms, and surgery can be performed when the
situation permits. Although pure puncture aspiration can quickly relieve
the clinical symptoms, after puncture aspiration, the cyst fluid flows
out, and the cyst volume is significantly reduced. As a result, pure
puncture aspiration is not conducive to surgery, and the cyst easily
recurs after puncture; thus, it is not recommended to puncture the cyst
before surgery.
Conclusion:
The symptoms of congenital tongue root cysts in infancy appear early but
lack specificity. For children with dyspnea and feeding difficulty,
electronic laryngoscopy, ultrasound, and neck CT should be performed in
a timely manner to make a clear diagnosis. It is vital for these
patients to be diagnosed and treated as soon as possible.
Figure-1
A Electronic laryngoscopy revealed that the cyst was located at the root
of the tongue, compressed the epiglottis, and was hemispherical. The
glottis was poorly exposed.
B Neck CT examination revealed a round cystic mass at the base of the
tongue, with a clear boundary and a diameter of about 16mm
C Pathological examination showed irregular fissure structure under
squamous epithelium with inflammatory cell infiltration
D Six months after operation, laryngoscopy showed that the cyst at the
base of the tongue was completely removed, and there was no sign of
recurrence.