DISCUSSION
Contact granuloma, also called larynx contact ulcer or vocal process
granuloma4. It is reported that the incidence of the
contact ulcer is approximately 0.9%-2.7% in voice
disorders5. It is more common in man than woman, more
precisely, man suffer 2~9 times large than woman among
the disease6 . The lesions usually appear in
unilateral vocal folds and sometimes bilateral vocal folds, and
typically in term of nodularation and epithelial ulceration of varying
degrees. The diagnosis of granuloma is very easy, generally based on
symptoms and laryngoscopy without biopsy, which is different from
laryngeal cancer. Pathologically, contact granuloma is not true
granuloma that because of lacking in cluster of mononuclear and
multinucleated histiocytes. They usually manifested as infiltration of
inflammation cells, capillary proliferation and fibrosis, and sometimes
as epithelial hyperplasia and perichondrium
keratosis7.According to a grading system by Farwell et
al8, clinical manifestations of the patient may be
asymptomatic or have varying degrees of voice disturbance, throat edema,
and varying levels of laryngeal discomfort and breathing difficulties.
Contact granuloma is always considered idiopathic when the common causes
like laryngopharyngeal reflux and anesthesia intubation are eliminated,
and some other causes are no-good habits of voice like incorrect
phonation and habitual throat clearing. That’s to say, The mechanical
irritation caused by bilateral vocal fold collision and the inflammation
caused by gastric acid reflux cause direct damage to the vocal fold
mucosa9. meanwhile, Smoking, inflammation, allergic
reaction, postnasal drip and social psychological pressure are also
important inducing factors of granuloma10. Only a few
patients can determine the reasons through application of reflux symptom
index and reflux finding score, and pharyngo-oesophageal 24-h pH
monitoring. The complexity of the causes makes the treatment difficult
and controversial. The current treatment for LCG mainly includes voice
correction, medication, surgical treatment and vocal fold injection.
Empirically, voice therapy and PPI is its first-line
treatment11. During the treatment cycle, patients are
instructed to silence their voices, try to avoid unconscious throat
clearing and coughing, and change incorrect phonation. At the same time,
patients need to improve their lifestyles to reduce laryngopharyngeal
reflux, including losing weight, reducing the amount of meals, and
avoiding lying down within 3 hours after eating, adhering to a low-fat
and low-acid diet, and avoiding intake carbonated or caffeinated
beverages and spicy stimulation food.
PPI are effciency in contact granuloma even though the patient do not
combined with laryngopharyngeal reflux12. However, the
treatment cycle of internal medicine is very long, and the average
treatment period is about 4.7 months13. Some patients
may experience gastrointestinal disorders such as diarrhea, nausea,
abdominal pain, or lack of gastric motility such as flatulence and
constipation or other symptoms. The recurrence rate up to 12.12% when
recurrent patient received PPI, and 3% even though combined with
injection corticosteroids into granuloma14.
Surgical treatment is usually considered in the case of drug treatment
failure or recurrence granuloma. Surgical removal were not recommended
by some researchers because of it can shrink the size of the granuloma
in the short term but has high rate of recurrence in the long
term11. An recent study indicate that The initial
non-surgical treatment (67 percent) has a much higher cure rate than
surgical treatment (30 percent) in contact granuloma
patients9. Jingyi Wu reported that given postoperative
radiotherapy within 24 hours can reduce the recurrence of laryngeal
granuloma effectively15. Vojko Djukic have studied
that Zinc supplementation for the treatment of granuloma of the larynx
is one of the conservative treatment16. Zinc affects
the healing process of wounds though the exact mechanism is unclear.
From Q Pham, botulinum toxin A injection threaten the powerful collision
and adduction of posterior portion larynx via relaxing lateral
cricoarytenoid muscle17. The collision of bilateral
arytenoid cartilage can cause local cartilage inflammation, mucosal
ulcers, and granulation tissue hyperplasia. Therefore, botulinum toxin A
injection can temporarily act on the denervated vocal fold muscles,
reducing the strong collision of the bilateral vocal folds and promoting
the repair of the vocal fold mucosa. The team’s previous research showed
that surgery combined withbotulinum toxin A injection is highly
effective in voice disorders18. A series of studies
also show that botulinum toxin A injection is safe and effective in the
treatment of LCG17,19. Botulinum toxin A injection
broaden the structure of the granuloma strategy from a chemical point of
view for the first time and transfer to innervated muscles and can be
alternative therapy under patients’ choice and institution’s situation
or applied to the failure on voice therapy or PPI 17,20.
The recurrence and refractory of LCG has always been the clinical focus
of attention of otolaryngologists. Regardless of the surgery strategy,
CO2 laser, angiolytic potassium titanyl phosphate laser or cold
instrument resection, it is difficult to achieve the desired effect in
the operation to remove the lesion alone. In this study, the pedicled
mucosal flap of ventricular band was transferred to the wound after
laser resection of granuloma, and the mucosa was anastomosed by
microsurgery. This is an update of the traditional operation of Ni Xin
et al21and solves the problem that the released
mucosal margin of the wound cannot completely cover the fresh wound,
which may resulting in easy recurrence. In this study, no matter the
size of granulomatous wound, we can take the pedicled mucosal flap to
completely close the wound, which eliminates the potential pathological
basis of granulomatous inflammation and achieves the purpose of one-time
basic cure. The acquisition and transfer of mucosal flap follows the
principle of voice surgery, staying in as a superficial plane as
possible and preserving the normal mucosa. It not only completely
excises the lesion, but also limits the lesion wound to the root of
granuloma, and completely reconstructs the cover-body of vocal fold
(epithelium plus superficial lamina propria), which is conducive to the
recovery of vocal fold mucosal wave and the prevention of local scar or
stenosis. At the same time, assisted microsurgery can avoid mucosal
avulsion and displacement, accelerate fibrosis of the mucosal flap wound
and granuloma wound. Secondly, the choice and acquisition of mucosal
flap is minimally invasive, easy to obtain and survive, which avoids
open surgical trauma and increases the survival rate of mucosal flap.
Recently, the combined treatment of vocal fold granuloma has
significantly improved the efficiency compared with the single
treatment, and has gradually become a trend 14,13, 22. This method combined with
botulinum toxin A injection reserve a time window for the recovery of
mucosal flap, also help to correct the phonation model and stabilize the
surgical effect. Postoperative PPI therapy is an important step to
consolidate the curative effect, control potential gastric acid reflux
and avoid recurrence. It can be seen that the concept of combined
treatment of LCG retains the advantages of various treatment methods,
which is of great significance for the thorough treatment of the
disease, and is an undeniable trend in the treatment of contact
granuloma.
Precision operability with great patience and caution is needed in the
surgery. The width of the pedicle should not be less than half of its
length in theory, so that the flap can survive. When suturing, the
surgeon should pay attention to the position of the needle and the
control of the wrist strength, the tension should be appropriate, the
torsion or fenestration of the pedicle of the microflap should be
prevented from necrosis of the mucosa, and the fully mucosal coverage of
the surgical wound is the key to the success of the operation.
Furthermore, experienced anesthesiologists will use a smaller diameter
endotracheal tube to expose the surgical field more clearly. At the same
time, when the glottis is exposed by endotracheal intubation, surface
anesthesia will be combined to reduce the fluctuation of vital signs and
hemodynamics during the operation.
After standardized medical
treatment and voice correction for 3 months, there was no significant
improvement in refractory LCG. It was suggested that local pedicled
mucosal flap transfer combined with botulinum toxin A injection should
be performed. As a preliminary study, there were no systemic or local
complications, high cure rate and low recurrence rate. The cure of the
disease also inspired the treatment of vocal fold scar, adhesion,
laryngeal stenosis, etc. we will continue to further clinical
observation and including more patients.