Correlation of tubal function and volume of mastoid and middle ear space as related to otitis media

The possible associations of septal deviation on mastoid pneumatization and chronic otitis

OBJECTIVES

The purpose of this study was to determine the role of nasal septal deviation on volume of mastoid air cells and possible relationship to chronic otitis.

MATERIALS AND METHODS

Between May 2010 and September 2012, paranasal sinus computed tomographic findings of 825 patients (470 male and 355 female subjects) who were treated in Ear Nose and Throat Department of Bozok University Medical Faculty were retrospectively analyzed. By excluding the other coexistent sinonasal pathologies, 100 patients (45 male and 55 female subjects; mean age, 37.7 ± 10.4 yr; range, 18-70 yr) with nasal septal deviations were recruited for the study. The convex side of the septal curvature was accepted as the direction of deviation. The findings were grouped according to the radiologically measured angle of nasal septal deviations. The deviation angle of the nasal septum was described as follows: mild (<9 degrees), moderate (9-15 degrees), or severe (≥ 15 degrees). The volume of each mastoid air cells was also calculated using the computer program. Chronic otitis was defined a abnormality criteria of the normal temporal scan. Criteria for a normal temporal bone were as follows: 1) absence of bony destruction or sclerosis; 2) absence of fluid or mass in any of the temporal bone air spaces; and 3) the presence of "normal" air cells.

RESULTS

There were 45 male and 55 female subjects (mean age, 37.7 ± 10.4 yr; range, 18-70 yr). Nasal septal deviation angles were found to range between 5 and 28.1 degrees (mean, 14 ± 1.2 degrees). The left-sided deviations included 16 mild (<9 degrees, Group I), 15 moderate (9-15 degrees, Group II), and 17 severe (≥ 15 degrees, Group III) subjects. The right-sided deviations included 18 mild (<9 degrees, Group I), 16 moderate (9-15 degrees, Group II), and 18 severe (≥ 15 degrees, Group III) cases. We could not demonstrate a statistically significant difference between the right mastoid cell volumes of the Group I and Group II in left-sided deviation cases (p = 0.51). In the same side comparison of Group I to Group III and Group II to Group III, the mastoid cell volume differences were found to be significantly meaningful (p = 0.00 and p = 0.00, respectively). Identical results were yielded in the right-sided septal deviation group related to the mastoid cell volumes of Group I and Group II and Group I to Group III and Group II to Group III comparisons (p = 0.55, p = 0.00, and p = 0.011, respectively). In both right and left deviation groups, ipsilateral and contralateral mastoid cell volume comparisons produced statistically significant results (p = 0.04 and p = 0.003, respectively). The presence of chronic otitis findings were significantly increased in both groups (p = 0.00). Statistical significance was set at p < 0.05.

CONCLUSION

Our findings suggest that mastoid cell volumes tend to be larger at the contralateral side of the severe septum deviations.

Prevalence of radiologic superior canal dehiscence in normal ears and ears with chronic otitis media

OBJECTIVES/HYPOTHESIS

Although labyrinth fistulae are caused mostly by cholesteatoma, they can occur in long-standing chronic otitis media (COM) without cholesteatoma. We aimed to compare the prevalence of radiologic SCD on computed tomography (CT) between normal ears and contralateral COM ears in patients with unilateral COM and to assess the prevalence of superior canal dehiscence (SCD) according to the age.

STUDY DESIGN

Case series with comparison performed at a tertiary care academic referral center.

METHODS

We retrospectively reviewed consecutive temporal bone CT scans of 759 patients with unilateral COM between 2009 and 2011. The mean (± standard deviation) age was 48 years (±14 years). Images were independently evaluated by two otologists, and the bone overlying the superior canal was characterized as normal, suspicious, or definite SCD.

RESULTS

The prevalence (3.4%) of definite SCD in COM ears was significantly higher than that (0.3%) in normal ears. The prevalence (6.6%) of suspicious or definite SCD in COM ears was also higher than that (1.2%) in normal ears. There was no correlation between the prevalence of SCD and age in either normal or COM ears. All of the normal ears with suspicious or definite SCD also showed contralateral suspicious or definite SCD (bilateral involvement).

CONCLUSIONS

Our present findings suggest that the COM is related to the presence of SCD. The roof of the temporal bone may become thin by the failure of postnatal bone development and susceptible to chronic brain pulsation and pressure exerted by the temporal lobe in COM ears.

How does childhood otitis media change the radiological findings of the temporal bone?

CONCLUSION

Inflammatory changes in the middle ear mucosa since childhood may affect mastoid pneumatization without a change in the position of the sigmoid sinus. Also, despite the fact that recurrences of inflammatory middle ear disease lead to bone destruction, we did not see any relationship between the childhood otitis media and bone destruction.

OBJECTIVE

To assess radiological findings in temporal bone in both healthy ears and diseased ears in patients with unilateral chronic otitis media since their childhood.

METHODS

Twenty-five patients who had unilateral otological symptoms, such as recurrent otalgia, purulent otorrhea or hearing loss since their childhood were included in the study. Assessment of radiological parameters was performed using a quantitative digital image processing computed tomography program.

RESULTS

Mastoid volume values in the chronic otitis media group were significantly smaller when compared with those of a healthy group (p < 0.05). In healthy and diseased mastoid groups, there were no significant differences between groups when we assessed Henle spine-sigmoid sinus (HS-SS) distances. There was a significant correlation (p = 0.001) in both the groups when we compared mastoid volume values with HS-SS distances. There was ossicular discontinuity in two cases and in one patient tegmen tympani was not intact in diseased ears.

Variation and modalities of growth and development of the temporal bone pneumatization in Neandertals

The temporal bone is used frequently to determine taxonomic affinities as it contains several features that differentiate Neandertals from anatomically modern Homo sapiens. However, only little information is available about temporal bone pneumatization in Neandertals. This study provides descriptions and comparisons of the disposition and the extensiveness of the pneumatization of the temporal bone in large samples of Neandertal specimens of different geological and developmental ages (25 individuals and 33 temporal bones from the sites of Engis, Krapina, La Chapelle aux Saints, La Ferrassie, La Quina, Pech de l'Azé, and Spy). Although temporal bone pneumatization shows some individual variability, a similar pattern of distribution is found in all adult Neandertal individuals from Krapina and Western Europe. Pneumatization is restricted mainly to most parts of the petromastoid areas. We also retrace for the first time the modalities of growth and development of this pneumatization in Neandertals. Finally, this study provides new information about possible correlations between the extension and position of temporal bone pneumatization and some of the morphological features used to characterize the temporal bone of the Neandertals. These latter features include the relatively low and short temporal squama, the robust zygomatic process with a relatively marked lateral projection, the strong supramastoid crest, the significant thickness of the tympanic part of the temporal bone, and the relatively small mastoid process and large juxtamastoid eminence. Our results suggest that the development of pneumatization in Neandertals is related to available space and to temporal bone morphology. Moreover, it appears that the development of pneumatization does not play an active role in determining the morphology of the apomorphic features of the temporal bone in Neandertals.

Cranial base morphology and temporal bone pneumatization in Asian Homo erectus

The external morphological features of the temporal bone are used frequently to determine taxonomic affinities of fossils of the genus Homo. Temporal bone pneumatization has been widely studied in great apes and in early hominids. However, this feature is rarely examined in the later hominids, particularly in Asian Homo erectus. We provide a comparative morphological and quantitative analysis of Asian Homo erectus from the sites of Ngandong, Sambungmacan, and Zhoukoudian, and of Neandertals and anatomically modern Homo sapiens in order to discuss causes and modalities of temporal bone pneumatization during hominid evolution. The evolution of temporal bone pneumatization in the genus Homo is more complex than previously described. Indeed, the Zhoukoudian fossils have a unique pattern of temporal bone pneumatization, whereas Ngandong and Sambungmacan fossils, as well as the Neandertals, more closely resemble the modern human pattern. Moreover, these Chinese fossils are characterized by a wide midvault and a relatively narrow occipital bone. Our results support the point of view that cell development does not play an active role in determining cranial base morphology. Instead, pneumatization is related to available space and to temporal bone morphology, and its development is related to correlated morphology and the relative disposition of the bones and cerebral lobes. Because variation in pneumatization is extensive within the same species, the phyletic implications of pneumatization are limited in the taxa considered here.

Computerized assessment of the mastoid air cell system

There have been many arguments on the development of pneumatization of temporal bone. However, a technique for direct volume measurement from high resolution computed tomography has never been reported. The aim of this paper is to develop a technique by using digital image processing to measure the volume of the mastoid air cell system. Forty three ears of 26 healthy subjects (13 males and 13 females) without a history of chronic or exudative otitis media, clear signs of Meniere's disease, severe sensorineural hearing impairment or malformation of temporal bone were eligible for enrolment in this study. Using a digital image processing technique, only the black air cells and tympanic cavity on the CT films are easily selected. Then, after image processing, only areas of these extracted black pneumatized parts are calculated. Consequently, the volume of pneumatized parts of temporal bone could be calculated separately as total volume and as partial volume that divided by several CT planes. The average volume of pneumatization in 43 temporal bones was 5.97 ml. However, since the volume of pneumatization in the temporal bone has traditionally been estimated by analyzing areas on X-ray films, the new method described in this study is significant for its ability to directly measure the volume of pneumatization in the temporal bone.

A community-based nursing approach to the prevention of otitis media

Otitis media (OM), a disease of the middle ear, is one of the most common diseases of childhood. Although the medical and surgical treatment of the disease by physicians is covered at length in the literature, information about the role of nurses in dealing with OM is scant. The purpose of this article is to propose a community-based nursing prevention plan for OM based on what is known about its prevalence and pathogenesis.

Size variation of mastoid air cell system in Indian people at different age groups: a radiographic planimetric study

A radiographic planimetric study of mastoid air cell system was carried out on 100 normal human subjects of which 50 were males and 50 females--who were further subdivided into five age groups. They had no history of past ear disease or any other clinical ENT abnormality. The mean area of the mastoid air cell system was measured planimetrically on X-rays and the data analysed according to age and sex. It was 12.05 +/- 0.67 cm2 in males and 11.45 +/- 0.70 cm2 in females (which are more or less the same as that of Western people). The size of the cranial bones has no apparent role in the size variation of the mastoid air cell system. The development of the latter was very rapid up to 10 years of age in both sexes and it continued even after 20 years of age but at a much slower rate.

Value of middle ear inflation as a diagnostic indicator of eustachian tube patency

The value of tubal inflation as a diagnostic procedure for Eustachian tube patency and function is controversial. In an attempt to assess the diagnostic value of air douche in atelectatic ears, 49 such ears of 40 patients were politzerized. The procedure was successful in 45 ears. However, of the four unsuccessful cases, two of the patients were able to autoinflate their ears. These results show that air douches pass regularly through the Eustachian tube into the tympanic cavity even in atelectatic ears, which by definition suffer from aeration deficiency, which is often considered to be secondary to 'Eustachian tube obstruction', or alternatively 'Eustachian tube dysfunction'. Thus, the ability to force air through the Eustachian tube by politzerization is of no diagnostic value as an indicator of normal or abnormal tubal patency or functioning in atelectatic ears and most probably in allied conditions.

Anthropological study of the mastoid air cell system in Pakistani races

This is an anthropological study of the development of the mastoid process in the four ethnic groups of Pakistani races: Turko-Iranian, Indo-Aryan, Scytho-Dravidian, and Aryo-Dravidian. Cephalometric studies have established that the majority of Pakistanis are brachio to ultra-brachiocephalic (Cephalic Index 82-x). Radiological evaluation of normal mastoids and their planimetric measurements show that the mastoid process is smaller (Av: 10.24 sq.cm. +/- 0.8) than the Caucasian Western races (Av: 12-15 sq.cm.). Neither combined approach tympanoplasty, nor mastoid obliteration technique may be required, nor technically possible in a small mastoid. Natural epithelization of a small 'peanut size' mastoidectomy cavity does not justify these procedures. A modified radical mastoidectomy and tympanoplasty reconstruction provides a satisfactory result in chronic discharging ears.

The infant's eustachian tube lumen: the pharyngeal part

A study of Eustachian tube measurements in infants and children is presented. The study included 33 Eustachian tubes from normal temporal bones and 10 Eustachian tubes from temporal bones harbouring acute otitis media. The temporal bones underwent histologic serial sectioning. The lumen of the Eustachian tube's first portion, i.e. the pharyngeal part, was measured with the aid of a grid mounted on a microscope. These measurements show: A. The Eustachian tube lumen grows and enlarges to a small extent with age. B. Each age group presents a considerable variation in the range of area of the lumen comparable with the natural biological distribution. C. No statistical difference was found between the size of the pharyngeal portion of the lumen of the Eustachian tube from temporal bones which had acute otitis media and those coming from non-pathological ears. This comparison took into consideration age and physiological distribution. These findings are similar to our earlier findings regarding the isthmic region.

Caliber of the lumen of the eustachian tube pre-isthmus in infants and children

We measured the eustachian tubes in temporal bones taken from infants and children. These specimens included eustachian tubes from 35 normal temporal bones and 13 temporal bones containing acute and secretory otitis media. All temporal bones were serially sectioned for histological studies. The lumen of the third portion of each eustachian tube (i.e., the pre-isthmus or the physiological isthmus) was measured with the aid of a grid mounted on a microscope. These measurements showed: (1) the eustachian tube lumen grows and enlarges to a small degree with age; (2) each age group has a considerable variation in the size of the lumen which is compatible with natural biological distribution; (3) no statistical differences were found in the size of the pre-isthmus lumina of those eustachian tubes from temporal bones showing acute or secretory otitis media when compared with the lumina of eustachian tubes in non-pathological ears.

The eustachian tube midportion in infants

The eustachian tube midportion in infants and children was measured in 44 eustachian tubes from normal temporal bones and 11 eustachian tubes from temporal bones harboring acute otitis media. The temporal bones were serially sectioned, and the lumina of the eustachian tubes' midportions were measured with the aid of a grid mounted on a microscope. These measurements showed that the eustachian tube lumen grows to a small degree with age. Each age group showed a considerable variation in the range of the luminal area compatible with natural biologic distribution. No statistically significant difference was found in the sizes of the midportions of the eustachian tube lumina from temporal bones that harbored acute otitis media when compared with the lumina of the eustachian tube midportions from normal ears.

The human Eustachian tube lumen in children. I. The isthmus

A study of Eustachian tube measurement in infants and children is presented. The study comprised 53 Eustachian tubes from normal temporal bones and 17 Eustachian tubes from temporal bones harbouring acute and secretory otitis media. The temporal bones underwent histologic serial sectioning. The lumen of the Eustachian tube isthmus was measured with the aid of a grid mounted on a microscope. These measurements show: A) the Eustachian tube isthmus lumen does grow and enlarge slightly with age; B) each age group presents a considerable range in area, compatible with a natural biological distribution; C) no statistical difference was found in the size of isthmus lumens obtained from temporal bones which had been affected by acute or secretory otitis media, when compared with lumens of Eustachian tubes coming from non-pathological ears. This comparison took into consideration both age and physiological distribution.

The temporal bone in patients with Meniere's disease

Sixty-three patients with Meniere's disease were compared with a group of healthy individuals with respect to findings at tomography and plain radiography. The temporal bone in patients differed in many respects from that in the healthy controls. Characteristic features in patients were a lack of periaqueductal pneumatization, a lack of pneumatization medial to the arcuate eminence, a short vestibular aqueduct, a narrow external aperture of the vestibular aqueduct, and a reduction in size of the mastoid air cell system. The mean mastoid area in the diseased ear in patients was 7.93 cm2 and in controls 11.59 cm2. The vestibular aqueduct was visible in its full length on tomograms in 81% of the healthy controls and in 65% of the diseased ears in patients. The mean volume of the mastoid air cell system in Meniere patients, determined at operation, was 5.3 ml.

Comparative anatomy of eustachian tube and middle ear cavity in animal models for otitis media

The comparative anatomy of the normal eustachian tube (ET) and normal middle ear cavity of three animal species (rat, gerbil, and chinchilla) is described relating to the usefulness of these animals as models for otitis media (OM). Routine histological and anatomical techniques and procedures were used. The gerbil and chinchilla, although of different sizes, are quite similar, having hypertrophied middle ear bullae, nearly vertical ET, and similar histology including seromucous glands draining directly into the ET. In contrast, the rat has a small bulla, a nearly horizontal ET, and a large concentration of goblet cells but few mucous glands in the ET. It appears that the chinchilla and the gerbil may serve as alternative models for OM research. Chinchillas and gerbils are relatively free of naturally occurring OM, while the rat has a high incidence of naturally occurring OM.

Temporal bone pneumatization. A planimetric study

This present study is based on the results of a planimetric investigation of temporal bone pneumatization in 73 children (with and without middle ear pathology). Radiologic and clinical follow-up studies indicate a definite inhibition of pneumatization due to chronic secretory or recurrent suppurative otitis media. This process is partially reversible if the underlying pathologic ventilation of the middle ear spaces is cured by an adequate treatment, such as direct adenoidectomy and/or long-term middle ear ventilation (6 months indispensable).

Intratympanic gas-pressure in cases of SOM and atelectasis

Direct manometric measurement of gas pressure in the middle ear, by piercing the tympanic membrane with a hollow needle, has been made leak-free. Even so, the rather small negative pressures (a few mm of H2O2) found in cases of secretory otitis media (SOM) and in atelectatic ears, are in error due to a previously unsuspected, significant correction factor. For the proper application of the correction, the volume of the free gas-space in each ear would have to be known. This volume was unavailable to us for the individual ear, yet in cases like ours it ranges between 0.5 to 2.5 ml and therefore an average of 1.2 ml was assumed. Our results, calculated on this basis, were -34 +/- 86 mmH2O and -9 +/- 86 mmH2O for 24 cases of SOM and 32 cases of atelectasis respectively. Like all previous measurements, there too show a large scatter. This is accounted for by two factors (i) the use of the average instead of the individual ear volume, (ii) actual fluctuation in middle ear aeration and therefore of pressure, pointing to the fact that underaeration is a functional disorder rather than an obstruction of the Eustachian tube.

Meniere's disease and the mastoid pneumatization

The size of the mastoid penumatization was radiographically examined and planimetrically measured in the patients with Meniere's disease, patients with other sensorineural hearing loss and clinically ear healthy persons. Law projection was used for the radiographical examination. No statistical differences were seen among the three groups. Meniere's disease and the factors which influence the mastoid pneumatization are discussed.

Aeration in chronic otitis media

The mastoid air cell system must be looked upon as an air reservoir. The tympanic membrane is an air pressure regulator. The smaller the air volume of the mastoid the more pronounced is the volume displacement of the tympanic membrane. The more inefficient the Eustachian tube function, the more pronounced is the tympanic membrane displacement. The significance of these factors must be considered not only when discussing the etiology of chronic otitis media including cholesteatoma, but also when it comes to selecting procedures in restoring middle ear anatomy and physiology in chronic middle ear surgical disease.