The impact of nasal surgery on air-conditioning of the nasal airways.

Air-conditioning in the nasal passageways is one of the most important functions of the upper airways. By means of in-vivo-measurements and numerical simulation, the air-conditioning function of the nose has been extensively investigated. Less well known is the effect of nasal surgery on the nasal climate. The following study presents a summary of the effect of various rhino-surgical operations, i.e. turbinoplasty, septoplasty, septorhinoplasty, repair of septal perforations, functional and radical sinus surgery, on the air-conditioning function of the nose. Nasal and sinonasal interventions have been demonstrated to be associated with increased nasal heating and humidification when the mucosal lining is preserved. Radical interventions with reduction of turbinate tissue cause reduced nasal warming and moistening within the nasal airway, with increased risk of nasal dryness and crusting. Although the impact of the nasal cycle and the airflow distribution within the nasal cavity on nasal temperature and humidity distribution is not fully understood yet, too much widening of the nasal cavity by sinunasal interventions has carefully to be avoided.

Dynamic nasal infrared thermography in patients with nasal septal perforations.

BACKGROUND: Nasal obstruction is a typical symptom in patients with nasal septal perforations. Rhinomanometry and acoustic rhinometry are not reliable in these cases because the perforations generate incorrect results. Infrared thermography camera (ITC) systems allow contact-free intranasal recordings of the nasal surface temperature and the semiquantification of nasal airflow. The aim of this study was to perform contact-free temperature measurements of the nasal vestibular surface by application of ITC systems in patients with septal perforations to investigate the disturbed intranasal heat exchange and nasal airflow. METHODS: The surface temperature profiles within the nasal vestibules of healthy volunteers (n=10) and patients with septal perforations (n=3) were recorded with an ITC during several breathing cycles. Thermal images were taken (60/s) displaying the surface temperature in degrees centigrade corresponding to a color scale. RESULTS: The temperature recordings showed a disturbed intranasal heat exchange during inspiration and expiration in patients with septal perforations in comparison with healthy subjects. A reduced and irregular inspiratory cooling of the entire surface within the nasal vestibules visualizes a reduced and disturbed airflow volume. CONCLUSION: The study was able to prove the feasibility of intranasal temperature recordings of the surface with an ITC system in patients with septal perforations. Contrary to rhinomanometry and acoustic rhinometry, thermography cameras can be applied to examine airflow in patients with septal perforations. The detected reduced cooling of the surface during inspiration might be a possible explanation for the patients' feelings of nasal obstruction.

Effect of carboxymethylcellulose nasal packing on wound healing after functional endoscopic sinus surgery.

BACKGROUND: Functional endoscopic sinus surgery (FESS) has become the treatment of choice for patients with medically resistant chronic rhinosinusitis. Nasal packing is usually placed after the surgery to support wound healing and prevent adhesions. The purpose of this study was to investigate the effect of carboxy-methylated cellulose (CMC) nasal packing on wound healing after FESS compared with no nasal packing. METHODS: Twenty-six patients underwent bilateral FESS. The patients were randomized to receive CMC mesh or gel packing on one side and no packing on the opposite side. The patients were followed at 2, 4, and 12 weeks after surgery. Endoscopically visible CMC, crusting, mucosal integrity, synechia formation, granulation tissue formation, and adverse side effects were assessed and documented. RESULTS: No adverse side effects were observed. No significant differences were found between the CMC-packed side and the unpacked side with respect to the outcome measure of wound healing. No difference was found between two different forms of CMC in terms of wound healing. Two weeks after surgery, endoscopically visible CMC was detected in four patients of the CMC mesh group, whereas none of the patients in the CMC gel group had endoscopically visible CMC (p = 0.040). CONCLUSION: As we were unable to establish an effect, we must question the efficacy of this packing material and the necessity of its use after FESS based on the technique of the Graz University Medical School. The mesh form of CMC could be potentially useful as a vehicle for extended drug delivery owing to its longer retention time in the nose.

CMC packing in functional endoscopic sinus surgery: does it affect patient comfort?

BACKGROUND: Functional endoscopic sinus surgery (FESS) has become the treatment of choice for patients with medically resistant chronic rhinosinusitis (CRS and nasal polyposis). Nasal packing is usually placed after the surgery to minimize mucosal bleeding and support the wound healing process. Both the packing itself and its removal are often associated with pain and discomfort. OBJECTIVE: To evaluate the effect of carboxymethylcellulose (CMC) nasal packing on patient comfort following FESS. METHODS: Forty consecutive patients underwent bilateral FESS. One side of the nasal cavity was packed with CMC (mesh or gel) and the opposite side was not packed, the sides having been randomly selected. Postoperatively, patients were given visual analog scales to rate nasal airway obstruction and headache/pressure separately for the right and left sides. They also rated sleep disturbance and general well-being. RESULTS: No significant differences were found between the CMC-packed side and the unpacked side with regard to patient comfort. No significant differences were found between CMC mesh and CMC gel. CONCLUSION: Based on the presented data concerning patient comfort, CMC appears to be an ideal packing material following FESS. However, there is no other study revealing an identical study design focusing on other resorbable packing material. As a consequence, other available resorbable packing material should be investigated to find the ideal packing material following FESS, if packing is required.

Dynamic infrared thermography of the nasal vestibules: a new method.

OBJECTIVE: The surface temperature distribution within the nasal vestibule and the nasal cavity strongly depends on the exact intranasal detection site and point of time during the respiratory cycle. Therefore, conventional temperature measurements e.g. with thermocouples only provide selective measurements. The use of infrared thermography cameras could present a new contactless method with a high spatiotemporal resolution. The aim of the present study was to evaluate the use of infrared thermography camera systems for measurements of the nasal surface temperature during respiration. METHODS: The surface temperature profiles within the nasal vestibules of healthy volunteers were recorded with infrared thermography cameras during several breathing cycles. Two different types of infrared thermography standard systems were used. RESULTS: The recordings allowed a display of temperature alterations within the nasal vestibules in a high spatiotemporal resolution synchronous to the breathing cycle. During inspiration, the vestibular surface cooled down presenting a non-homogenous distribution (range, 24.7 to 30.2 degrees C). During expiration, the vestibular surface was warmed again with a non-homogenous distribution (range, 33.1 to 36.2 degrees C). The results of both camera systems were comparable. CONCLUSION: Infrared thermography cameras allow the exact mapping of nasal surface temperature within the nasal vestibules with a high spatiotemporal resolution without surface contact.

Control of bleeding following functional endoscopic sinus surgery using carboxy-methylated cellulose packing.

The aim of this study is to evaluate the haemostatic effect of carboxy-methylated cellulose (CMC) nasal packing following functional endoscopic sinus surgery (FESS). The design includes an investigator-initiated, randomized, single-blinded, controlled, prospective clinical study. A bilateral FESS procedure was performed on 41 patients. At the end of the operation, one side was randomly filled with CMC nasal packing, the other side remained without packing. The patients were blinded to the side of nasal packing and were postoperatively examined on the 1st day, after 2 and 4 weeks and the extent of the postoperative bleeding was quantified with a clinical grading system. Even though there were slightly more postoperative bleedings reported for the non-packed sides as compared to the CMC-packed sides, these differences were at no point statistically significant within the monitored postoperative period of 4 weeks. In the examined collective, the CMC packing investigated did not statistically prove to have an effect on bleeding control in this study design.