Correction of low-set ear: superoposterior mobilization of the ear as a transposition flap pivoted on the ear canal with burring of the superoposterior canal wall

In a number of congenital, developmental, and postoperative conditions, many patients have a difference in the vertical and anteroposterior position of the ears. On correction of this deformity, the most difficult problem is the low and anterior location of the external auditory canal. To overcome this unyielding limitation, the authors perform superoposterior transposition of the low-set ear pivoted on the ear canal after making a new path for the canal by burring of the thick superoposterior canal wall. A mastoid hairline incision is followed by three-quarters circumferential subpericranial dissection around the bony ear canal posteriorly. A preauricular incision is followed by subcutaneous dissection anteriorly. By using the natural deformability of the cartilaginous ear canal, the S-shaped canal can be straightened through a new path made by burring of the thick superoposterior wall. Then the low-set ear can be mobilized superoposteriorly as a transposition flap pivoted on the ear canal with minimal tension by straightening of the canal. The corrected auricular position can be maintained by (1) several permanent sutures between the cavum conchae and the mastoid and deep temporal fascia, (2) a suspensory temporoparietal fascial loop, and (3) a skin support provided by the repair in an elevated position and V-Y-plasty or Z-plasty on the lower pole of the ear. From December of 1997 to October of 1998, three cases with a maximum follow-up of 15 months were examined. Symmetric ear position was achieved and maintained on both frontal and lateral views after the operation in all cases. This new technique for correction of low-set ear produces symmetric ear position in both vertical and anteroposterior dimensions for a long time. In addition, it can be performed with various other surgical procedures safely and simultaneously in a variety of pathologic conditions.     

湿型外耳道分泌物的菌群结构及其药物敏感性分析

人的外耳道中存在种类繁多的微生物。为了解健康人湿型外耳道分泌物中的细菌数量、种类及其对药物敏感性,收集了38例无耳道疾病健康人左、右耳的湿型外耳道分泌物76份。采用分离培养的方法进行平板涂布、菌落计数及鉴定,分析其菌群数量及种类;通过纸片扩散法(Kirby-Bauer纸片扩散法)对分离的细菌进行药物敏感性试验,并利用头孢硝噻吩纸片检测青霉素耐药株产β-内酰胺酶情况。结果显示,88.3%的湿型外耳道分泌物的菌群数量在1×10² CFU/mL～1×10⁶ CFU/mL;共检出细菌20种,其中球菌占97.1%,主要为葡萄球菌;杆菌为2.9%。分离率前4位的细菌为头葡萄球菌、耳葡萄球菌、人葡萄球菌和表皮葡萄球菌,对临床常用的妥布霉素、米诺环素、万古霉素和呋喃妥因等抗生素敏感率达90.0%以上;对复方新诺明和青霉素耐药率相对较高,但低于50.0%。分离得到的132株葡萄球菌中,25株对青霉素耐药,耐药株的β-内酰胺酶阳性率为44.0%。结果提示,从健康人湿型外耳道分泌物中分离的细菌种类多样,以葡萄球菌为主,对临床常用的抗生素有较高的敏感性,但对青霉素、复方新诺明等具有一定耐药性。     

Prevalence of Chlamydia trachomatis and genital mycoplasmas in asymptomatic women.

To establish the prevalence of Chlamydia trachomatis, Mycoplasma hominis and Ureaplasma urealyticum in women attending a family planning and a prenatal clinic in Halifax, cervical swabs were obtained at the time of the first visit from 491 women who had no symptoms of genital infection. Among the women attending the family planning clinic M. hominis occurred in combination with C. trachomatis more frequently than expected (p less than 0.05). It occurred in the absence of U. urealyticum in only a few cases (13% of the occurrences in the family planning clinic and 6% of those in the prenatal clinic). C. trachomatis was significantly more prevalent in women under 25 years of age (p less than 0.04). However, mycoplasmas were as prevalent in women over 30 years as in those under 30. There were no significant differences in the infection rates of the organisms by trimester among pregnant women. More research is necessary for a proper understanding of the role of M. hominis and U. urealyticum in genitourinary infections and pregnancy outcomes.     

Ultrastructure of elastic cartilage in the rat external ear

Summary The structure of elastic cartilage in the external ear of the rat was investigated by transmission and scanning electron microscopy.The narrow subperichondrial, boundary zone contains predominantly ovoid cells rich in cell organelles: mitochondria, Golgi complex, granular endoplasmic reticulum and small (40–100 nm) vesicles. Scarce glycogen granules and bundles of 6–7 nm cytoplasmic filaments are also present. Deeper in the boundary zone, one or more cytoplasmic lipid droplets appear and cytofilaments become more abundant.Fully differentiated chondrocytes in the central zone of the cartilage plate resemble white adipose cells. They are globular and contain a single, large cytoplasmic lipid droplet. The cytoplasm is reduced to a thin peripheral rim; it contains a flattened nucleus, few cytoplasmic organelles and abundant, densely packed, cytoplasmic filaments.The intercellular matrix is very sparse. The pericellular ring consists of collagen fibrils about 20 nm in diameter and a proteoglycan cartilage matrix in the form of a stellate reticulum. The complex of these two structures appears in the scanning electron micrographs as a network of randomly oriented, ca 100 nm thick fibrils. Spaces between pericellular rings of matrix also contain thick elastic fibers or plates, apparently devoid of microfibrils. In scanning electron micrographs elastic fibers could be detected only in a few areas, in which they were not obscured by other constituents of the matrix. Immature forms of elastic fibers, oxytalan (pre-elastic) and elaunin fibers, were found in the perichondrial and boundary zones.     

Origins of the mycoplasmas: sterol-nonrequiring mycoplasmas evolved from streptococci.

We report the establishment of a phylogenetic relationship between the sterol-nonrequiring mycoplasmas (Acholeplasma species) and streptococci. Three specific antisera prepared against purified Streptococcus faecalis fructose diphosphate aldolase and glyceraldehyde-3-phosphate dehydrogenase and Pediococcus cerevisiae glyceraldehyde-3-phosphate dehydrogenase were used for comparative enzyme immunological studies; the Ouchterlony double-diffusion technique and the quantitative microcomplement fixation procedure were employed. The reactions obtained provide evidence showing that all seven ACholeplasma species studied (A. laidlawii, A. granularum, A. modicum, A. oculi, A. axanthum. A. hippikon, and A. equifetale) are phylogenetically related to streptococci and that they evolved from streptococci. The data strongly suggest that the acholeplasmas comprise a distinct evolutionary group that has diverged from streptococci belonging to Lancefield group D or N. No reactions were observed between these enzyme antisera and cell extracts from six fermentative Mycoplasma species. These results support the view that mycoplasmas are derived from various bacteria.     

Directionality of sound perception in the external ear of the dog

Sound pressure level of tone was measured using a probe tube microphone at entrance to the dog's external meatus as a function of the azimuth of the sound source. It was demonstrated that directionality of the dog's external ear and corresponding values of interaural intensity differences (delta I) were gradually increased as the tone frequency raised from 0.5 to 40 kHz. Transfer in pinnae locations from lateral to frontal positions (one of the components of orientation reaction to an unexpected sound) resulted in some narrowing of directionality diagrams and in a displacement of their maxima towards the head midline. It was calculated that owing to this effects the extent of monotonic part of the function relating delta I and azimuth of a source were enlarged. The lateral pinnae position was suggested to be optimal for sound detection and the frontal one for localization of the moving sound source.     

A morphometric study of the external ear: age- and sex-related differences

The human ear is a defining feature of the face. Its subtle structures convey signs of age and sex that are unmistakable yet not easily defined. With analysis of normative cross-sectional data, this study explored anatomic and aesthetic differences in the ear between men and women, as well as changes in ear morphology with age. A total of 123 volunteers were randomly selected for this study. The cohort consisted of 89 women ages 19 to 65 years (median age, 42 years) and 34 men ages 18 to 61 years (median age, 35 years). The average total ear height across the entire cohort for both left and right ears was 6.30 cm, average lobular height was 1.88 cm, and average lobular width was 1.96 cm. As expected based on head size, significant sex-related differences were noted in the distance from the lateral palpebral commissure to both the helical root and insertion of the lobule. Measured distances in both vectors were approximately 4.6 percent longer in men than in women. Similarly, the height of the pinna was significantly larger in men than in women by approximately 6.5 percent. The average height and width of the lobule, however, were nearly identical in men and women. Analysis of age-related data showed a significant difference in the total ear height between the subpopulations; however, this difference was not significant after the lobular height was subtracted from total ear height, suggesting that the lobule was the only ear structure that changed significantly with age. In addition, lobular width decreased significantly with age. This study establishes normative data for ear morphology and clearly demonstrates the changes in earlobe morphology that occur with advancing age.     

Detection of Alloiococcus otitidis in the nasopharynx and in the outer ear canal

Alloiococcus otitidis has been recovered from the middle ear of children with otitis media with effusion, but its natural habitat is not known. To determine whether the nasopharynx and the outer ear canals are the natural habitats of A. otitidis, 145 swabs (50, nasopharynx; 95 outer ear canal) collected from 50 children were screened by polymerase chain reaction. A. otitidis DNA was detected in seven (4.8%) of the 145 specimens, of which four were nasopharynx, and three outer ear canal. These results indicate that the nasopharynx and outer ear canal may be the body sites for localization of A. otitidis.     

Synchronization of estrus and fertility in goats with norgestomet ear implants

Estrus was synchronized in 64 dairy goats in July with norgestomet ear implants. Half the does received ear implants that contained 6 mg norgestomet and the remaining does received implants that contained 3 mg. Implants were left in place for 11 days. Each doe received i.m. injections of 400 IU PMSG and 50 mug cloprostenol 24 hours prior to implant removal. Twenty-eight of 32 does (87.5%) that received 6 mg or 3 mg norgestomet exhibited onset of estrus within 24 hours of implant removal. All does had exhibited onset of standing estrus by 43 hours after implant removal. Does were hand-mated to fertile bucks twice daily while in standing estrus. There were no differences between does implanted with 6 mg or 3 mg in fertility to the induced estrus (74.2% vs 75% kidding), mean length of gestation (151.0 +/- 3.2 vs 151.6 +/- 2.0 days), mean number of kids per doe (2.1 +/- 0.8 vs 2.3 +/- 0.7) or in mean kid weights (3.10 +/- 0.80 vs 3.06 +/- 0.86 kg) (6 mg vs 3 mg, respectively). It was concluded that ear implants that contained 3 mg of norgestomet were equally as effective as implants that contained 6 mg for synchronization of estrus in dairy goats.