The developing temporal bone: computed tomography measurements and assessment of suture closure from birth to 18 years of age.

PURPOSE: To describe the normal CT appearance of the developing temporal bone in children from birth to 18 years of age. METHODS: Two hundred and six temporal bone CTs of children from 0.14 to 18.95 years were retrospectively selected and reviewed. Temporal bones were measured in a standardized slice orientation using the length of the basal turn of the cochlea, the length and width of the petrous bone, the coronal extent, trailing edge and anterior-posterior dimension of the temporal bone and the angle between petrous bone's length and the midsagittal line in the axial plane showing the basal turn of the cochlea in its greatest extent. Two sutures, two synchondroses and three fissures of the temporal bone were evaluated and graded. RESULTS: Chosen measurements and calculations demonstrate an increase of values from 0 to 18 years with the greatest increase occurring during the first 2 years of life. The angle between the basal turn of the cochlea and the midsagittal line shows a large variability. Logarithmic trend lines illustrate larger measurements of males as compared to females. The ratio of the basal turn of the cochlea and the length of the petrous bone is about 1:4.1 (f/m) during the first year of life and about 1:6.1 (f)/1:6.8 (m) from 17 years onwards. Results of suture closure are described using box-and-whisker plots. CONCLUSIONS: The developing temporal bone grows the most during the first 2 years of life. Knowledge of changing proportions and suture closure is essential for evaluation of temporal bone CT of children.

Some Remarks on Imaging of the Inner Ear: Options and Limitations.

The temporal bone has a highly complex anatomical structure, in which the sensory organs of the cochlea and the vestibular system are contained within a small space together with the sound-conducting system of the middle ear. Detailed imaging is thus required in this anatomical area. There are a great many clinical aims for which the highest-possible spatial resolution is required. These include the localization of cerebrospinal fluid fistulas, the detection of malformations of the middle and inner ear and the vestibulocochlear nerve, an aberrant course of the facial nerve and anomalies of the arterial and venous structures, the confirmation of dehiscence of the semicircular canals and finally, the verification of endolymphatic hydrops in cases of Ménière's disease. However, the term 'high resolution' is very time dependent. Two milestones in this respect have been (in 1991) the 3D visualization of the inner ear by means of maximum-intensity projection (MIP) of a T2-weighted constructive interference in steady state (CISS) sequence of a 1.5-tesla magnetic resonance imaging (MRI) scanner (Tanioka et al., Radiology 178:141-144, 1991) and (in 1997) imaging of the vestibulocochlear nerve for the diagnosis of hypoplasia inside the internal auditory canal using the same sequence (Casselman et al., Radiology 202:773-781, 1997).The objective of this article is to highlight the options for, and the challenges of, contemporary imaging with regard to some clinical issues relating to the inner ear.

Radiological anatomy - evaluation of integrative education in radiology.

PURPOSE: Evaluation and analysis of the integrative course "Radiological Anatomy" established since 2007 at the Medical School Hannover (MHH) in comparison with conventional education. MATERIALS AND METHODS: Anatomy and radiology are usually taught separately with a considerable time lag. Interdisciplinary teaching of these associated subjects seems logical for several reasons. Therefore, the integrative course "Radiological Anatomy" was established in the second year of medical education, combining these two closely related subjects. This interdisciplinary course was retrospectively evaluated by consideration of a student questionnaire and staff observations. The advantages and disadvantages of integrative teaching in medical education are discussed. RESULTS: The course ratings were excellent (median 1; mean 1.3 on a scale of 1 to 6). This is significantly (p < 0.001) better than the average of all evaluated courses in the respective term (grade 2.8). The course improved the anatomical comprehension (90 %) and the students stated that the topics were relevant for their future medical education (90 %). Furthermore, interest in the subject's anatomy and radiology increased during the course (88 %). According to the students' suggestions the course was enhanced by a visitation in the Department of Radiology and the additional topic central nervous system. CONCLUSION: Integrative teaching of anatomy and radiology was well received by the students. Both, anatomical and radiological comprehension and the motivation to learn were improved. However, it should be considered, that the amount of work and time required by the teaching staff is considerably increased compared to traditional teaching.

[The role of CT in the diagnosis of peritonsillar abscesses after Punctio Sicca]. / Stellenwert der Computertomografie in der Peritonsillarabszessdiagnostik nach Punctio sicca.

BACKGROUND: Peritonsillar abscesses are considered to be complications of a peritonsillar inflammation and are a frequently occurring condition. Often, to confirm the presence of an abscess and to locate it following a dry-tap aspirate, computed tomography (CT) is performed. No validated data has been published to date concerning the role of CT in the diagnosis of peritonsillar abscesses. MATERIAL AND METHODS: In a retrospective analysis, the records of patients presenting at a German university hospital with a suspected peritonsillar abscess between 2006 and 2011 were evaluated. A particular focus was placed on the diagnostic procedure for patients with dry tap. The CT images were evaluated by 2 neuroradiologists. RESULTS: 310 patients with a suspected peritonsillar abscess from the period 2006­2011 were evaluated. In 51 cases (31 male and 20 female patients; 16.5 %), a dry tap was found to have occurred. Of these, in 42 patients (82.3 %) a CT scan was performed to rule out or locate an abscess. In 36 patients (85.7 %), an abscess was verified by CT imaging. CONCLUSION: Where there are clinical grounds for suspecting a peritonsillar abscess, and where a dry tap occurs, our data indicate that performing a CT scan to verify and locate an abscess is an effective diagnostic procedure. However, greater attention should be paid to additional diagnostic methods.

Influence of earthworms on the sulfur turnover in the soil.

Abstract The effects of earthworm activity on the concentration and isotopic composition of total sulfur in soils was investigated using batch experiments. Two ecologically different lumbricid species, the anecic Lumbricus terrestris and the endogeic Aporrectodea caliginosa, were used. The earthworms were fed birch leaves, beech leaves, cattle manure or mixed plant litter. All food sources differed isotopically (δ(34)S) from the soil (Parabraunerde). As a reference, one experiment was carried out without additional food. The experimental results show, that both earthworm species influence the total S-content and the δ(34)S-values in the soil by digestion of the different food sources. The differences in the total S-content of the earthworm tissues and in the S-isotopic composition of the casts can be attributed to the ecological differences between the earthworm species.

Sulfate Reduction in a Forested Catchment as Indicated by δ(34)S Values of Sulfate in Soil Solutions and Runoff.

Abstract In a forested catchment in the Fichtelgebirge mountains (NE-Bavaria, Germany) the long term SO(4) (2-) budget (average 1988-1994) indicated that about 40% of the input with throughfall (16.8 kg SO(4) (2-) S·ha(-1)·yr(-1)) was retained in the catchment. In order to identify processes acting as potential SO(4) (2-) sinks, δ(34)S values of SO(4) (2-) in soil solutions and runoff were measured between May and November 1994. δ(34)S values of the runoff and the fen were higher (5.8‰) than the δ(34)S values of the soil solution of the oxic soils in the terrestrial area (3.9‰). Because there is no lithogenic S source within the catchment, it can be assumed that SO(4) (2-) deposition is the only S source in the catchment. Thus the results were interpreted as a result of SO(4) (2-) reduction within the catchment, because the uptake of (32)S is favoured during the dissimilatory SO(4) (2-) reduction and (34)S is consequently enriched in the soil solution. To estimate the amount of SO(4) (2-) reduced isotopic fractionation factors between - 9‰ and -46‰ were considered, resulting in SO(4) (2-) reduction rates of 1.8-9.3 kg SO(4) (2)-S·ha(-1)yr(-1). It was concluded that besides dissimilatory SO(4) (2-) reduction another sink exists in the catchment (e.g. SO(4) (2-) sorption in deep soil layers).

Cyanogenesis inhibits active defense reactions in plants.

In the course of fungal attack on the cyanogenic rubber tree (Hevea brasiliensis Muell.-Arg.) HCN is liberated from infected tissue. The HCN interferes with plant host and fungal pathogen. It becomes inhibitory to active defense responses which are dependent on biosynthetic processes as far as a threshold concentration is transgressed.