Keywords mucociliary clearance - nasal obstruction - turbinates
Introduction
Nasal obstruction is one of the most common symptoms encountered by otorhinolaryngologists
in clinical practice. It is usually caused by hypertrophy of the inferior turbinate.
Among the surgical methods commonly used to treat nasal obstruction due to turbinate
hypertrophy are cryosurgery, electrocautery, partial turbinectomy, laser turbinoplasty,
and radiofrequency thermal ablation (RFTA).[1 ]
The primary goal of therapy is to maximize the nasal airway for as extended a period
of time as possible while minimizing therapeutic complications, such as crust formation,
nasal drying, hemorrhage, and edema.[2 ]
Preserving mucosal surfaces and nasal epithelial function during reduction of the
hypertrophied inferior turbinate is important for mucociliary clearance (MCC) because
MCC is a primary defense mechanism in the upper respiratory system.[3 ] MCC can be measured by various techniques. The saccharin test is a simple test used
to evaluate MCC. In the presence of normal mucociliary action, the saccharin is swept
backward to the nasopharynx and a sweet taste is perceived by the patient.[4 ]
The aim of this study was to assess the efficacy of RFTA and bipolar electrocautery
(BEC). Patients with inferior turbinate hypertrophy treated with either of these procedures
were also evaluated in terms of postoperative morbidity. The advantages and disadvantages
of each treatment were discussed.
Patients and Methods
From October 2014 to December 2014, 23 patients (10 women, 13 men) who underwent RFTA
and 20 patients (11 women, 9 men) who underwent BEC were recruited. Inclusion criteria
for both groups were nasal obstruction caused only by inferior turbinate hypertrophy
and age over 18 years. Patients with deviation of the nasal septum or diseases such
as allergic rhinitis and sinonasal infections were excluded, as were smokers. Subjective
assessments of nasal patency, MCC, and postoperative morbidity (edema, nasal bleeding,
and crusting) were determined using a visual analog scale (VAS), the saccharin clearance
test (SCT), and endoscopic examination, respectively. This study was performed in
accordance with the Helsinki Declaration of the World Medical Association and was
approved by the Research Ethics Committee of a tertiary referral center. Surgeries
were performed under local anesthesia.
For RFTA, the probe was placed longitudinally and submucosally in the anterior, middle,
and posterior portions of the turbinate. The procedure was completed by applying 350 J
of energy for 20 seconds in each of the three areas. For BEC, a bipolar probe delivering
20 W of energy was inserted between the submucosa and periosteum in the anterior,
middle, and posterior portions of the turbinate. Bipolar cauterization was stopped
when minimal coagulation of the nasal mucosa was achieved, as determined visually
by whitening of the treated tissues. The conchal and periosteal mucosae were preserved.
Patients in the RFTA and BEC groups underwent VAS evaluation and an SCT before and
2 months after the respective procedure. SCT time was measured by placing a fourth
of a saccharin tablet (5 mg saccharin) behind the anterior edge of the inferior turbinate.
The interval between the beginning of the test and the point at which the taste was
perceived by the patient was recorded in seconds. In the VAS evaluation of nasal patency,
a score of 0 indicated no nasal obstruction and 10 complete nasal obstruction. Edema,
nasal bleeding, and crusting were assessed via nasal endoscopic examination performed
postoperatively during routine weekly visits. The date when each sign disappeared
was recorded. Statistical analysis was performed using the Statistical Package for
Social Sciences, version 20.0 for Windows software (SPSS Inc., Chicago, Illinois,
United States). A two-tailed t test was used for descriptive statistical analysis (mean ± standard deviation) of
quantitative data. A p value < 0.05 was considered to indicate statistical significance.
Results
The mean age of the patients was 32.08 ± 7.42 years in the RFTA group and 29.66 ± 9.33
years in the BEC group. In the RFTA group, the mean preoperative MCC was 561.3 ± 69
second (range: 465 to 713 seconds and the VAS score for nasal patency was 7.13 ± 0.9.
Postoperatively, the corresponding values were 560.8 ± 64 seconds (range: 450 to 725 seconds
and 3.56 ± 0.8). The pre- and postoperative VAS scores, but not the MCC values, were
significantly different (p = 0.001 and p = 0.86, respectively). In the BEC group, the mean MCC was 570.6 ± 61 seconds (range:
435 to 735 seconds before treatment and 584.9 ± 61 seconds (range: 460 to 690 seconds
2 months after treatment, and the difference between two tests was not statistically
significant (p = 0.75). Mean VAS score for nasal patency was 7.1 ± 1.13 before treatment and 3.4 ± 1.0
2 months after treatment, and the difference between the two results was statistically
significant (p = 0.001). [Tables 1 ] and [2 ] present the SCT and VAS data for the RFTA and BEC groups. No bleeding was observed
in either group. Edema and crusting in the turbinate disappeared in all patients by
the end of the first week. [Figs. 1 ] and [2 ] show the turbinates pre and postoperatively for both techniques.
Table 1
Saccharin clearance test results
Preoperative
Postoperative
p
[a ]
Radiofrequency thermal ablation (s)
561.3 ± 69
560.8 ± 64
0.86
Bipolar electrocautery (s)
570.6 ± 61
584.9 ± 61
0.25
a Two-tailed t test.
Table 2
Visual analog score results
Preoperative
Postoperative
p
[a ]
Radiofrequency thermal ablation
7.13 ± 0.9
3.56 ± 0.8
0.001
Bipolar electrocautery
7.1 ± 1.13
3.44 ± 1
0.001
a Two-tailed t test.
Fig. 1 Right inferior turbinates before and after radiofrequency thermal ablation.
Fig. 2 Left inferior turbinates before and after bipolar electrocautery.
Discussion
Reduction of the volume of the inferior turbinate can be achieved by a variety of
methods. Turbinate reduction procedures should cause minimal patient discomfort and
few or no adverse effects while preserving the physiologic function of the turbinate,
such as MCC.[2 ] Surgical treatments of the inferior turbinate may lead to deterioration of MCC by
damaging the nasal mucosa. The MCC system is important in defense of the upper and
lower respiratory tracts. In patients undergoing turbinate reduction, a damaged nasal
mucosa and impaired MCC have been implicated in many postoperative side effects such
as bleeding, crusting, dryness, defective sense of smell, pain, hyposmia, synechia,
and osteonecrosis.[5 ] Several methods are available to assess MCC activity. In this study, we used the
SCT, which is reliable, simple, and inexpensive.[6 ]
RFTA is a widely used treatment for nasal obstruction caused by turbinate hypertrophy.
The technique is based on local submucosal transport of energy by means of a specifically
adapted electrode. The applied energy increases the local temperature of the deep
mucosa and causes a thermal lesion without damaging the mucosal surface. The healing
process secondarily induces fibrosis and wound contraction, resulting in a reduction
in tissue volume.[7 ]
In BEC, an electrical circuit is established between two probe tips. The resulting
thermal energy induces coagulation and thus a reduction in the vascularity and volume
of tissue, both in the short and long term. The depth of the burn and lateral thermal
injury are less when bipolar rather than unipolar devices are used.[8 ]
The effects of RFTA on MCC and nasal patency have been investigated in several studies.
Uz et al and Parida et al used the SCT and VAS to evaluate the efficacy of RFTA and
the postoperative morbidity associated with the procedure.[5 ]
[9 ] They reported no adverse effects of RFTA on mucociliary activity and a significant
improvement in VAS scores. Duran and Ulkü obtained similar results with respect to
MCC.[10 ] Cukurova et al assessed the long-term (60 months) results of RFTA based on VAS scores
and acoustic rhinometry measurements.[11 ] The cited authors concluded that significant long-term improvements could be achieved
with RFTA. Our study confirms these findings.
Taneja and Taneja compared monopolar cauterization, bipolar cauterization, and diathermy,
evaluating outcomes with the SCT.[12 ] All three techniques led to significant improvements in the quality of life but,
based on the SCT values, none yielded significant long-term results. In addition,
the authors found that BEC, when performed over the turbinate mucosa, triggered histologic
changes involving the transformation of columnar epithelium into cuboidal or squamous
epithelium, due to burn injury. The importance of submucosal cauterization while preserving
the mucosa was emphasized.[12 ] Kilavuz et al assessed RFTA and BEC by VAS, inspiratory peak flowmetry, and magnetic
resonance imaging.[13 ] They reported significant improvements in the VAS scores and inspiratory peak flowmetry.
They noticed that although RFTA and BEC techniques are effective treatment methods,
BEC technique is superior to RFTA to achieve high efficiency.
In our patients, the SCT times and VAS scores obtained with the two procedures were
comparable and in agreement with results reported in the medical literature. It can
therefore be concluded that RFTA and BEC are both effective to improve nasal patency
without damaging MCC or causing complications such as bleeding, edema, and crusting.
In addition, although cost analysis was not an aim of this study, the economic differences
between the two techniques should not be underestimated. BEC equipments are inexpensive
and can be used repeatedly, unlike RFTA equipments.
Conclusions
Submucosal cauterization with preservation of the nasal mucosa and periosteum is an
effective, inexpensive, and safe method to achieve a reduction in inferior turbinate
hypertrophy.
