A new parameter for the management of positional plagiocephaly: the size of the anterior fontanelle matters.

PURPOSE: The rate of positional plagiocephaly has increased since guidelines for the prevention of sudden infant death have led to the recommendation of positioning infants on their back during sleeping. Therapy includes repositioning, physiotherapy, and helmet therapy. To date, there is no consensus on the treatment of positional plagiocephaly. Therefore, it was the goal of this study to compare the results of physiotherapy and helmet therapy and to investigate if the size of the anterior fontanelle can be used as an additional parameter for the indication of the helmet therapy. METHODS: We enrolled 98 infants with a diagonal difference of 7 mm or more and plagiocephaly classified as Argenta II or more. Patients were grouped into infants with a small anterior fontanelle (< 25mm2) and infants with a large anterior fontanelle (≥ 25mm2). The patients were observed for at least 18 months. Sixty-eight patients were treated with repositioning and physiotherapy, whereas 30 infants received helmet therapy. RESULTS: The remolding rate was significantly higher with the helmet therapy than with physiotherapy. In patients with a small fontanelle, a lower spontaneous remolding rate was seen pointing to their lower correction potential. Especially in these patients, plagiocephaly was reduced significantly more quickly with the helmet treatment than with physiotherapy, so that they may benefit from the helmet due to their otherwise reduced spontaneous remolding capacity. CONCLUSION: The helmet therapy led to a faster reduction of the asymmetry than physiotherapy in this study. In patients with a small anterior fontanelle and therefore lower remolding potential, the helmet treatment was more effective than physiotherapy.

Prospective documentation and analysis of the pre- and early clinical management in severe head injury in southern Bavaria at a population based level.

Treatment of patients suffering from severe head injury is so far restricted to general procedures, whereas specific pharmacological agents of neuroprotection including hypothermia have not been found to improve the outcome in clinical trials. Albeit effective, symptomatic measures of the preclinical rescue of patients (i.e. stabilization or reestablishment of the circulatory and respiratory system) or of the early clinical care (e.g. prompt diagnosis and treatment of an intracranial space occupying mass, maintenance of a competent circulatory and respiratory system, and others) by and large constitute the current treatment based on considerable organizational and logistical efforts. These and other components of the head injury treatment are certainly worthwhile of a systematic analysis as to their efficacy or remaining deficiencies, respectively. Deficits could be associated with delays of providing preclinical rescue procedures (e.g. until intubation of the patient or administration of fluid). Delays could also be associated in the hospital with the diagnostic establishment of intracranial lesions requiring prompt neurosurgical intervention. By support of the Federal Ministry of Education and Research and under the auspices of the Forschungsverbund Neurotraumatology, University of Munich, a prospective system analysis was carried out on major aspects of the pre- and early clinical management at a population based level in patients with traumatic brain injury. Documentation of pertinent data was made from August 1998 to July 1999 covering a catchment area of Southern Bavaria (5.6 mio inhabitants). Altogether 528 cases identified to suffer from severe head injury (GCS < or = 8 or deteriorating to that level within 48 hrs) were enrolled following admission to the hospital and establishment of the diagnosis. Further, patients dying on the scene or during transport to the hospital were also documented, particularly as to the frequency of severe head injury as underlying cause of mortality. The analysis included also cases with additional peripheral trauma (polytrauma). The efficacy of the logistics and organization of the management was studied by documentation of prognosis-relevant time intervals, as for example until arrival of the rescue squad at the scene of an accident, until intubation and administration of fluid, or upon hospital admission until establishment of the CT-diagnosis and commencement of surgery or transfer to the intensive care unit, respectively. The severity of cases studied in the present analysis is evident from a mortality of far above 40% of cases admitted to the hospital, which was increased by about 20% when including prehospital mortality. The outcome data notwithstanding, the emerging results demonstrate a high efficacy of the pre- and early clinical management, as indicated by a prompt arrival of the rescue squad at the scene, a competent prehospital and early clinical management and care, indicative of a low rate of avoidable complications. It is tentatively concluded on the basis of these findings that the patient prognosis is increasingly determined by the manifestations of primary brain damage vs. the development of secondary complications.

Tissue compatibility and biodegradation of new absorbable stents for tracheal stabilization: an experimental study.

Newly designed absorbable stents for temporary tracheal stabilization were implanted into the trachea of 35 Wistar rats. The stents consisted of Vicryl filaments in a homogeneous PDS melt. Compatibility and biodegradation were investigated over a study period of up to 24 weeks. After the animals were killed, the trachea was examined with an optic and scanning electron microscope. During the first 2 weeks erosive mucosal defects appeared in the trachea, as well as distinct polyps of granulation tissue, focal metaplasia of the epithelium, and inflammatory infiltrates of the lamina propria. During the period leading to the sixth week, the granulations flattened and mild fibrotic alterations evolved. After the eighth week no stent residues could be detected, whereas only slight signs of chronic fibrotic inflammation persisted. No evidence for aspiration of foreign bodies or progressive inflammatory changes of the mediastinum was found.

Recognition of damage in polarizing transmission-grating facets.

An optical setup was built for microscopic damage inspection on transmission-grating facets composed of a gold-wire structure. Contrast improvement was achieved by exploiting the polarizing properties of these gratings in the near-infrared region. Spatial filtering yields an additional contrast enhancement and reduces unwanted signals caused by the periodic support structure. An image-processing algorithm is developed that evaluates the number and the size of the faults in a grating facet with high accuracy from only one digital image.

Polarimetry of transmission gratings.

We have investigated the polarizing properties of gold wire gratings in the resonance domain. The partial polarizing properties of 1-µm period gratings in the near IR are then used to orient the wire structure of transmission grating facets parallel to each other by means of an alignment polarimeter technique. The absolute alignment accuracy for these gratings is limited by the influence of the support structure on the orientation of the polarization ellipse. If the polarizing properties of this perturbative component are known, the accuracy can be enhanced by treating the polarization by means of the Mueller calculus.

Highly conducting wire gratings in the resonance region.

We present a theoretical approach for calculating the fields diffracted by gratings made of highlyconducting wires that have a rectangular shape. The fields between the wires are represented in terms of modal expansions that satisfy the approximated impedance boundary condition. Our results show thatthis procedure is particularly suited to dealing with gold gratings used in the infrared range, a spectral region where the assumption of a perfect conductor does not hold, and where the rigorous modal method assuming penetrable wires exhibits numerical instabilities linked with the high conductivity of gold. Numerical results are presented, and the theory is used to determine wire parameters by fitting theoretical and experimental data.

Characterization of x-ray transmission gratings.

Self-supporting transmission gratings with periods of 1 microm or below are used in combination with grazing-incidence telescopes in celestial x-ray astronomy. They can be produced with sizes up to only a few cm(2); therefore, several hundreds or even thousands of individual elements are needed in order to cover the aperture of a telescope. This large number leads to the problem of characterization of the gratings regarding their x-ray performance. We demonstrate that spectrometry in the resonance domain using H polarization is a suitable method for the determination of the grating wire profile and deviations of the grating surface from a plane. Although developed originally for microwave applications it can be shown that the methods of strict solution of the Helmholtz equation are able to explain even small effects related to imperfections of periodic submicrometer structures.