Discussion
Caustic ingestion of household cleaner by children aged 2-6 years
accounted for 80% of cases of caustic injury. The severity of the
injury depends on a number of factors, such as the property (acid or
base), state and quantity of the substance. Acids produce coagulation
necrosis, causing cicatrices, while alkalis produce liquefaction
necrosis, immediately leading to severe penetrating damage. As to
physical form, the rapid flow of liquid substances not only damages the
mouth and pharynx, but also causes digestive tract
burns[2, 3]. Due to the protective effect of the
epiglottis, the vocal cords are generally not damaged, which explains
why hoarseness is uncommon in these patients.
Pharyngeal stenosis is a complication caused by ingestion of harmful
substances, total laryngectomy, chemoradiation, or malignant tumors. The
cases of pharyngeal stenosis surgery caused by caustic ingestion are
few. Berlucchi M[4] and Velasco
KJS[5] chose the same way of removing the stenosis
directly and applying mitomycin C to prevent the stenosis. We sought
improvement upon this foundation.
How to prevent fibrosis and recurrence postoperatively is always a
challenge to surgeon. Whether using a cold instrument or CO2 laser,
simple excision of the tissue increases the risk of postoperative
recurrence and scar formation. Many researchers have worked on this
problem. Placement of laryngeal stent and graft of intervening tissue
has been proven to improve phonation[6, 7]. Yılmaz
T[8] first proposed the concept of butterfly
mucosal flap. The sutured flaps covered raw surfaces, thus diminishing
the risk of reformation of web postoperatively. Subjective and objective
voice indicators and ventilation were significantly improved with this
technique. In opinion of the author, besides smearing chemical drugs
like mitomycin and steroids, these methods are all about diminishing the
contact of surgical wounds to prevent recurrence. This technique is
based on the same principle.
In the surgical treatment of glottic web, the removal of excess mucosa
is controversial. Schweinfurth[9] recommended
removal of excess mucosa directly, while Yılmaz
T[8] suggested that the mucosal flap was
insufficient to cover all the exposed mucosal surface and thus should be
preserved. However, this problem is absent in the hypopharyngeal
stenosis area in consequence of the larger mucosal area. But there is a
fact that the flap shrinks during the development process. It should be
noted that the flap should not be too small and the tension should not
be too high during the process of making the mucosal flap and suturing.
At the beginning of the operation, the anesthesiologist should stop
supplying pure oxygen and instead supply mixed air to prevent the airway
from burning due to the laser. Tracheotomy and insertion of nasogastric
tube after pharyngoplasty are often difficult to avoid. In this case,
the patient’s parents were very resistant to tracheotomy and nasal
feeding. Finally, the patient did not suffer these means, and achieved
satisfactory therapy effect.
It is the first case in which CO2 ablation and mucosal flap suture have
been applied conjunctively to the treatment of pharyngeal stenosis
caused by caustic ingestion. This new attempt yielded satisfactory
results. Upholding the principle of covering the bare mucosal wound, the
method could be applied to similar diseases, such as pharyngeal web, but
it still needs more study and clinical practice.
Conclusion :
Pharyngoplasty with mucosal dislocation incision and complementary
suture is an effective technique to resect stenosis and prevent the
recurrence. More case studies are needed to practice and validate the
effectiveness of this technology in treating pharyngeal adhesions and
stenosis.