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Objective: The foramen of Luschka is a natural hole between the fourth ventricle and the subarachnoid space of the cerebellopontine angle (CPA). The obstruction of the foramen is a rare entity with primary and secondary forms. The secondary form is a result of various pathologies, while the primary [for full text, please go to the a.m. URL], 69. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit der Mexikanischen und Kolumbianischen Gesellschaft für Neurochirurgie

Goals Periarticular fat pads of the human knee are relatively well studied structures, but the majority of the reviewed articles focus on fat pads of the anterior part of the knee. Therefore, the goal of this scoping systematic review is to summarize and disseminate current knowledge about the only fat pad in the posterior part of the knee – the pericruciate fat pad (PCFP). Methods In November 2020 two independent researchers, in order to gather the maximally broad set of articles pertaining to the studied topic, searched the following databases: PubMed, Embase, Karger, Scopus, using terms: pericruciate fat pad, PCL fat pad, posterior cruciate ligament fat pad. The article inclusion criteria was that it contained any scientific or clinical data about the PCFP, regardless of the type of article (original study, case report, review), and the year of its publication. Article exclusion criteria were that the study was not related to the PCFP and the article was written in any other language than English. In order to write each section of this review the included studies were then sorted into subtopics related to the PCFP. Main findings During the initial search of medical databases only eight articles mentioning the PCFP were identified, and only four directly focused on the PCFP. PCFP is located in the intercondylar fossa, filling the space between cruciates near their femoral attachment sites, surrounding the posterior cruciate ligament (PCL) and directly contacting the posterior capsule of the knee joint. The PCFP is composed of fatty tissue, covered by a thin synovial layer. It can be visualized on a magnetic resonance imaging (MRI) and during arthroscopy. Injuries of the PCFP may occur, resulting in nonspecific posterior knee pain. It has been proposed that alterations of the PCFP signal in MRI were a secondary sign of acute anterior cruciate ligament (ACL) injury, and an early indicator of osteoarthritis of the knee joint. While functions of the PCFP are not yet well studied, the PCFP is hypothesized to be a container of reparative stem cells. In agreement with this hypothesis, „the PCL fat pad transfer technique” was described as a promising treatment to enhance synovialization and revascularization of the ACL, after its repair or reconstruction. Conclusions Anatomy and imaging of PCFP is relatively well studied, however, we still need additional studies concerning its histology, functions, injuries, and a role in osteoarthritis. While there are theoretical promising benefits of using PCFP in ACL repair or reconstruction, high level-of-evidence research is needed to formulate any stronger opinions on the topic.

Background The bicipital tunnel is the extra-articular, fibro-osseous structure that encloses the long head of the biceps tendon. Methods Twelve cadaveric shoulder specimens underwent in situ casting of the bicipital tunnel with methyl methacrylate cement to demonstrate structural competence (n = 6) and en bloc harvest with gross and histologic evaluation (n = 6). The percentage of empty tunnel was calculated histologically by subtracting the proportion of cross-sectional area of the long head of the biceps tendon from that of the bicipital tunnel for each zone. Results Cement casting demonstrated that the bicipital tunnel was a closed space. Zone 1 extended from the articular margin to the distal margin of the subscapularis tendon. Zone 2 extended from the distal margin of the subscapularis tendon to the proximal margin of the pectoralis major tendon. Zone 3 was the subpectoral region. Zones 1 and 2 were both enclosed by a dense connective tissue sheath and demonstrated the presence of synovium. Zone 3 had significantly greater percentage of empty tunnel than zones 1 and 2 did ( P Conclusion The bicipital tunnel is a closed space with 3 distinct zones. Zones 1 and 2 have similar features, including the presence of synovium, but differ from zone 3. A significant bottleneck occurs between zone 2 and zone 3, most likely at the proximal margin of the pectoralis major tendon. The bicipital tunnel is a closed space where space-occupying lesions may produce a bicipital tunnel syndrome. Careful consideration should be given to surgical techniques that decompress both zones 1 and 2 of the bicipital tunnel.

We report a methodology for computing functional vascular density within a rodent dorsal window chamber model based on long-exposure laser speckle imaging (LSI). This technique relies on the presence of flow to create detailed vasculature maps. Employing this contrast mechanism is not possible using conventional imaging methods. Additionally, a freeware algorithm for computing functional vascular density (FVD) from images acquired using long-exposure LSI is also described to facilitate ease in adopting this method. We demonstrate that together these tools can be used to compute FVD nearly twelve times faster than manual computation, yet with with comparable accuracy.

OBJETIVO: Avaliar e comparar o posicionamento dos túneis ósseos na cirurgia de reconstrução do ligamento cruzado anterior (LCA) pela técnica artroscópica e pela técnica aberta através da artrotomia. MÉTODO: Foi realizado um estudo retrospectivo comparativo de 70 pacientes acometidos por lesão do LCA. Trinta e cinco pacientes foram submetidos à reconstrução do LCA por via aberta e 35 por via artroscópica utilizando a técnica via portal anteromedial. Todos os pacientes foram submetidos à reconstrução do LCA usando enxerto autólogo do terço central do tendão patelar fixado com parafusos de interferência. As radiografias pós-operatórias foram revisadas e o posicionamento do túnel femoral foi avaliado pelos métodos propostos por Harner e Aglietti, enquanto o túnel tibial foi avaliado pelo método proposto por Staubli e Rauschning. RESULTADOS: Foram observados 54 pacientes do sexo masculino e 16 do sexo feminino. A média de idade na ocasião do procedimento foi de 34 anos e três meses, variando de 17 a 58 anos. A técnica artroscópica mostrou-se mais precisa que a técnica aberta quanto ao posicionamento dos túneis ósseos, tanto femoral quanto tibial. CONCLUSÃO: Através da análise radiológica dos joelhos submetidos à reconstrução do LCA, observou-se que o posicionamento dos túneis ósseos, tanto femoral quanto tibial, apresenta menor variação quando a cirurgia é feita pela via artroscópica. OBJECTIVES: To evaluate and compare bone tunnel positioning in anterior cruciate ligament (ACL) reconstruction surgery using the arthroscopic technique and the open technique consisting of arthrotomy. METHOD: A comparative retrospective study on 70 patients with ACL lesions was conducted. Thirty-five patients underwent ACL reconstruction by means of the open technique and 35 by means of the arthroscopic technique using an anteromedial portal. All the patients underwent ACL reconstruction using an autologous graft from the middle third of the patellar tendon, fixed using interference screws. The postoperative radiographs were reviewed and the positioning of the femoral tunnel was evaluated using the methods proposed by Harner and Aglietti, while the tibial tunnel was assessed using the method proposed by Rauschning and Staubli. RESULTS: Fifty-four of the patients were male and 16 were female. Their mean age at the time of the procedure was 34 years and 3 months, with a range from 17 to 58 years. The arthroscopic technique was shown to be more accurate than the open technique for positioning both the femoral and the tibial bone tunnels. CONCLUSIONS: Radiological analysis on the knees subjected to ACL reconstruction showed that the positioning of both the femoral and the tibial bone tunnels presented less variation when the surgery was performed arthroscopically.

In 1994, the World Health Organization published diagnostic criteria for osteoporosis. Since then, many new technologies have been developed for the measurement of bone mineral at multiple skeletal sites. The information provided by each assessment will describe the clinical characteristics, fracture risk and epidemiology of osteoporosis differently. Against this background, there is a need for a reference standard for describing osteoporosis. In the absence of a true gold standard, this paper proposes that the reference standard should be based on bone mineral density (BMD) measurement made at the femoral neck with dual-energy X-ray absorptiometry (DXA). This site has been the most extensively validated, and provides a gradient of fracture risk as high as or higher than that of many other techniques. The recommended reference range is the NHANES III reference database for femoral neck measurements in women aged 20–29 years. A similar cut-off value for femoral neck BMD that is used to define osteoporosis in women can be used for the diagnosis of osteoporosis in men — namely, a value for BMD 2.5 SD or more below the average for young adult women. The adoption of DXA as a reference standard provides a platform on which the performance characteristics of less well established and new methodologies can be compared.

The periosteum is a thin layer of connective tissue that covers the outer surface of a bone in all places except at joints (which are protected by articular cartilage). As opposed to bone itself, it has nociceptive nerve endings, making it very sensitive to manipulation. It also provides nourishment in the form of blood supply to the bone. The periosteum is connected to the bone by strong collagenous fibres called Sharpey's fibres, which extend to the outer circumferential and interstitial lamellae of bone. The periosteum consists of an outer "fibrous layer" and inner "cambium layer". The fibrous layer contains fibroblasts while the cambium layer contains progenitor cells which develop into osteoblasts that are responsible for increasing bone width. After a bone fracture the progenitor cells develop into osteoblasts and chondroblasts which are essential to the healing process. This review discusses the anatomy, histology and molecular biology of the periosteum in detail.

White matter and the inner granular layer of rat cerebellum was analysed by imaging time-of-flight secondary-ion mass spectrometry (TOF-SIMS) equipped with a Bi+ ion cluster gun. Samples were prepared by high pressure freezing, freeze-fracturing and freeze drying or by plunge freezing and cryostat sectioning. The identified and localized chemical species were: sodium, potassium, phosphocholine, cholesterol and galactosylceramide (GalC) with carbon chain lengths C18:0 (N-stearoyl-galactosylceramide) and C24:0 (N-lignoceroylgalactosylceramide) with CH24:0 (hydroxy-lignoceroylgalactosylceramide). We report new findings regarding the organization of myelin in white matter. One is cholesterol-rich, ribbon-shaped 10-20 microm areas excluding Na+ and K+. The second finding is the different distribution of GalC C18 and GalC C24 in relation to these areas, where GalC C18 was localized in cholesterol-rich areas and GalC C24 was localized in Na/K-enriched areas. The distribution of GalC was in small spots, homogeneous in size, of 0.8-1.5 microm. Sample preparation with high pressure freezing allowed separate localization of sodium and potassium in tissue samples.

We measured arterial diameter as a function of generation number (#) in the arteriograms of six postmortem lung preparations from human infants aged 35 to 48 wks post-conceptional age (PCA). The log-log plot of mean diameter as a function of generation number revealed a linear decrease in mean and median diameter with increasing #, which was characterized by its slope alpha and intercept beta (linear regression). The mean arterial diameter per generation as well as the ratio (F) between mother and larger daughter branch and the relative ratio of asymmetry (A) between the larger and the smaller daughter branch was calculated. The values of F(#) and A(#) were found to be constant between 2 and 15 generations in individual lungs which is consistent with the pulmonary arterial tree exhibiting fractal properties. The averaged values (F and A within a subject) of F(#) and A(#) as well as alpha and beta were determined for each lung preparation and found to be constant from 35 to 48 weeks of age, revealing unchanged branching properties in the pre- and postnatal phase of human lung development.

The cave-dwelling (hypogean) form of the teleost Astyanax fasciatus is blind, having only subdermal eye rudiments, but nevertheless maintains intact opsin genes. Second generation offspring of a cross between these and the normally sighted surface (epigean) form inherit opsin genes from both ancestries. A study of the expressed hypogean opsins of the hybrids, in comparison to the epigean forms, was undertaken by microspectrophotometry. The hybrid population showed considerable variation in the visual pigments of double cones, with evidence for two groups of cells with λmax intermediate to those of the epigean pigments. Possible explanations for these intermediate pigments are discussed, including the hypothesis that they may represent hybrid genes similar to the genes for anomalous cone pigments in humans. Evidence was also found for ultraviolet-sensitive single cones and for an additional MWS pigment.

Summary Background Three-dimensional (3D) imaging of delicate, moving soft-tissue body parts is very difficult. Our understanding of the muscles that control lip movements is based largely on histological and cadaveric studies, which provide scant information about dynamic morphology. Our aim was to develop an innovative scanning technique for the imaging and reconstruction of dynamic orofacial morphology by use of 3D and four-dimensional (4D, ie, 3D plus time) ultrasonography. Methods Four volunteers (including one patient) underwent ultrasonography with 3D/4D imaging systems. To avoid deformation of the delicate orofacial structures, a water bath with an acoustic window was devised. The orofacial part was immersed in the bath throughout scanning, and a timer was used to synchronise lip movements with the 4D scan. Findings 4D views showed the functional differences in superficial and deep muscle groups of the lips, and clearly showed the changes occurring with movement of the lips and mouth. In the patient, a pathological layer and its extension corresponding to surface malformation were clearly identified. Interpretation We have developed a prototype device that has made possible 3D and 4D examination of orofacial anatomy and function. With further refinement of the device and improvement in 4D acquisition timing, this technique may offer a new way of dynamically imaging and quantifying many soft-tissue parts in 3D without deforming structure or disturbing function.

We present a general scheme for automatically building a morphometric anatomical atlas. We detail each stage of the method, including the non-rigid registration algorithm, three-dimensional line averaging and statistical processes. We apply the method to obtain a quantitative atlas of skull crest lines. Finally, we use the resulting atlas to study a craniofacial disease; we show how we can obtain qualitative and quantitative results by contrasting a skull affected by a mandible deformation with the atlas.

The salivary glands of Sphaerodema rusticum consist of paired principal and accessory glands. Each principal gland is made up of a superior and an inferior lobe; the latter is differentiated into 3 regions. The accessory glands are vesicular anteriorly and tubular posteriorly. The salivary ducts originate from the hilus of the principal glands; the accessory gland ducts also open into the hilus. The salivary ducts of 2 sides meet within the salivarium to form a very short common duct. Each lobule of the principal glands consists of a syncytial epithelium, enclosing a large lumen. The lobules open either into the central longitudinal canal or into another lobule. The inferior lobe homogenate contained protease and amylase, and that of the superior lobe only amylase. The accessory glands showed weak amylase activity; they also contained a watery fluid in the vesicular part.