Biomedical subjects

O Hilberg

Publications and source records attributed to O Hilberg.

28 records · Page 2Linked to original sources

PubMed1993

Septoplasty and compensatory inferior turbinate hypertrophy: a randomized study evaluated by acoustic rhinometry.

The present study deals with the indication for inferior turbinate surgery in cases of concomitant anterior septal deviation. We define, by acoustic rhinometry, the characteristics of the obstructed nose and define mucosal turbinate hypertrophy. A random sample of 80 patients with nasal obstruction and anteriorly located septal deviation were objectively evaluated by acoustic rhinometry pre- and post-operatively. All had septoplasty and half were randomly selected to have anterior inferior turbinoplasty performed in the side opposite to the major septal deviation. Severe septal deviation, expressed by a minimal cross-sectional area less than 0.4 cm2 was present in 37 patients. In this group inferior turbinate reduction seems advisable. In the wide side, the minimal cross-sectional area and the cross-sectional areas at 3.3 and 4.0 cm from the nostrils increased in the turbinectomy group and decreased in the non-turbinectomy group after correction of the septal deviation. In the group with less pronounced septal deviation no influence of turbinate reduction could be detected.

Adolescent↗

PubMed1993

Nasal airway geometry: comparison between acoustic reflections and magnetic resonance scanning.

To evaluate the accuracy of the acoustic reflection (AR) technique for determination of nasal cavity cross-sectional areas, the area-distance function of both sides of the nose was determined in 10 subjects and compared with magnetic resonance imaging (MRI). Interindividual variation for the correlation between MRI and AR was seen, but in general the areas from 1 to 6 cm into the nasal cavity measured by AR were larger than areas measured by MRI, especially where the surface was most convoluted. The total volume for this region was 6.47 +/- 1.83 (SD) cm3 for AR and 5.65 +/- 1.34 cm3 for MRI. It was demonstrated that this could be due to errors in calculation of the areas on the basis of MRI and AR. In the posterior part of the nasal cavity and the epipharynx, there was a convincingly higher correlation between acoustic measurements and a scan perpendicular to the assumed geometrical axis of the epipharynx than between acoustic measurements and coronal scanning. This indicates that the sound axis roughly follows the geometrical axis. In a model of two tubes (nasal cavities) joined in a larger tube (the epipharynx), closure of the posterior part of the latter revealed that the contralateral nasal cavity is likely to cause overestimation of the posterior part of the epipharynx during AR compared with MRI.

Adult↗

PubMed1993

Nasal reaction to changes in whole body temperature.

The changes in nasal patency following a 1.5 degrees C decrease or increase in whole body temperature were measured in 8 healthy young males, during and after 30 min of immersion in a 15 degrees C cold or a 40 degrees C warm bath, breathing air at the same temperature, in a cross-over experimental design. The nasal reactions were traced by consecutive measurements of changes in nasal cavity volumes by acoustic rhinometry. Swelling of the mucosa during cooling and an almost maximal shrinkage of the mucosa during heating were indicated by respectively a decrease and an increase in nasal cavity volumes. The reactions were determined predominantly by the whole body thermal balance, but were also influenced by the temperature of the inhaled air, either enhanced, reduced or temporarily reversed. The greatest change occurred in the nasal cavity, left or right, which differed most from the final state at the beginning of exposure due to the actual state of nasal cycle.

Adult↗

PubMed1992

Nasal packing after septoplasty.

A prospective study to compare 3 different types of nasal pack after septoplasty with or without a supplementary turbinectomy has been performed with respect to discomfort and complications caused by the packing and the short-term results evaluated 3 months after operation. Fingerstall packings gave less problems than either Merocel or hydrocortisone-terramycine gauze packs with ventilation tubes. They were easier to remove and were associated with less persistent secretion in the post-operative period. No definite advantage from the patient's point of view has been demonstrated by the use of tubes and nasal packing. An analysis of the nasal patency 3 months post-operatively by peak-flow index and acoustic rhinometry revealed no differences between groups.

Adolescent↗

PubMed1991

Acoustic rhinometry, used as a method to demonstrate changes in the volume of the nasopharynx after adenoidectomy.

Acoustic rhinometry is a method of investigating the geometry of the nasal cavity and the nasopharynx. An acoustic impulse is transferred to the nasal cavity and the reflected signal is analysed expressing the cross-sectional area in the nasal cavity and the nasopharynx as a function of the distance from the nostril. The method provides an accurate and objective measurement of the geometry of the nasal cavity and the nasopharynx in a non-invasive way. In a series of 20 children, age range 4-16 years, it has been possible to demonstrate the changes in the volume of the nasopharynx after adenoidectomy. The relation between the volume of the adenoid and the calculated change of volume in the nasopharynx is found to be proportional and highly significant (P = 0.0005). It is concluded that acoustic rhinometry, which is very easy to perform, gives a reliable, objective measurement of the amount of adenoid tissue in the nasopharynx. The results from these and future studies may help reduce the number of unnecessary adenoidectomies.

Adenoidectomy↗

PubMed1991

Acoustic rhinometry: values from adults with subjective normal nasal patency.

The nose with normal feeling of nasal patency, and no gross structural changes has been described in 82 individuals by acoustic rhinometry. Curves for one and both sides of the nasal cavity and before and after decongestion have been recorded. We have found that the minimal cross-sectional area (MCA) is located anteriorly in the nasal cavity; in some subjects it is localized at the head of the inferior turbinate and in other subjects more anteriorly at the nasal valve. After decongestion MCA moves even more anteriorly. Beyond the MCA the dimension of the nasal cavity increases, with maximal effect of decongestion at 4 cm from nostrils. Decongestion increases the total volume of the nasal cavity by 35%.

Acoustics↗

PubMed1990

Turbinate hypertrophy. Evaluation of the nasal cavity by acoustic rhinometry.

We used acoustic rhinometry to assess the geometry of the nasal cavity. The cross-sectional area of the nasal cavity as a function of distance from the nostrils was obtained. Seventeen patients with hypertrophy of the inferior turbinate and septal deviations were examined preoperatively and postoperatively; 34 normal subjects served as controls. The cross-sectional area at the anterior part of the nose suggested that skeletal hypertrophy of the inferior turbinate might be expected in the side opposite the main septal deviation. Unilateral inferior turbinoplasty seems advisable.

Acoustic Impedance Tests↗

PubMed1990

Evaluation of the effect of localized skin cooling on nasal airway volume by acoustic rhinometry.

Ten healthy subjects (four men and six women) were subjected to localized skin cooling by submersion for 5 min of both feet and, in another experiment, one hand and forearm into ice-cold water. Repeated measurements of nasal cavity volumes by a new method, acoustic rhinometry, showed characteristic patterns ranging from marked increases in volumes lasting the entire exposure period to transient monophasic or biphasic responses to no change at all. The pattern in individual subjects was reproducible with the two methods of cooling, and it could be characterized by five types when related to baseline measurements during the preexposure period. Because of large minute-to-minute variations, probably determined by local differences and fluctuations in blood flow in tissues through the nose, evaluation of induced changes in the nasal cavity volume cannot be based on single measurements as has frequently been done in the past by using rhinomanometry as the experimental method. The mechanisms behind the characteristic patterns in immediate human nasal response to local skin cooling challenge remains to be explored.

Adult↗

PubMed1989

Acoustic rhinometry: evaluation of nasal cavity geometry by acoustic reflection.

To study the geometry of the nasal cavity we applied an acoustic method (J. Appl. Physiol. 43: 523-536, 1977) providing an estimate of cross-sectional area as a function of distance. Acoustic areas in a model constructed from a human nasal cast, in the nasal cavity of a cadaver and in 10 normal subjects and two patients with well-defined afflictions of the nasal cavity, were compared with similar areas obtained by computerized tomography (CT) scans, a specially developed water displacement method, and anterior rhinomanometry. We found a coefficient of variation of the areas of less than 2% by the acoustic method compared with 15% for the rhinomanometric measurements. Acoustic areas correlated highly to similar areas obtained by CT scanning (r = 0.94) and by water displacement (r = 0.96). In two patients the acoustic method accurately outlined, respectively, a tumor in the nose and a septum deviation. It is concluded that this method provides an accurate method for measuring the geometry of the nasal cavity. It is easy to perform and is potentially useful for investigation of physiological and pathological changes in the nose.

Acoustics↗

PubMed1989

Acoustic rhinometry: evaluation of the nasal cavity with septal deviations, before and after septoplasty.

We introduce acoustic rhinometry as a new, objective method to assess the geometry of the nasal cavity. The cross-sectional area of the nasal cavity as a function of distance from the nostrils was obtained. A group of 21 patients with septal deformities was examined with acoustic rhinometry preoperatively and postoperatively. These values were compared with those of 21 normal control subjects. The minimal cross-sectional area (MCA) is located in the anterior part of the nose, and it shifts anteriorly under the effect of decongestion. The preoperative value of MCA is related to the location and severity of the anterior septal deformity. Postoperative smaller MCA found in the opposite side of that narrowed by a severe anterior septal deformity may be explained by the impact of septoplasty without reduction of a hypertrophic turbinate. A highly significant relation between MCA and the subjective feeling of nasal patency, before and after surgery, suggests that MCA is a valuable parameter to express nasal patency. Correction of posterior septal deformities is found to increase significantly the cross-sectional area posteriorly. The effect of decongestion in the postoperative values, however, suggests that the mucosa contributes even more to the cross-sectional area of the posterior part of the nose. Acoustic rhinometry seems very suitable for evaluation of the nasal cavity in cases where septoplasty and turbinoplasty is considered, as well as for the postoperative evaluation.

Adolescent↗