685 research outputs found
Jugular phlebectasia presenting as globus pharyngeus
Even though much has been written on the aetiology of globus pharyngeus, itstill remains elusive and multifactorial. We present a case of a 54-year-old womanwho was referred by an orthopedist to the radiology department with a 6-dayhistory of an intense feeling of “pressure” and “tightness” in the jugular notch.After performing a contrast-enhanced computed tomography scan, a phlebectasiaof the right anterior jugular vein was discovered. When trying to determinethe cause of the globus sensation one has to consider the possible existence ofa phlebectasia of one of the jugular veins
The biology behind the human intervertebral disc and its endplates
The intervertebral discs (IVDs) are roughly cylindrical, fibrocartilaginous, articulating structures connecting the vertebral bodies, and allowing movement in the otherwise rigid anterior portion of the vertebral column. They also transfer loads and dissipate energy. Macroscopically the intervertebral disc can be divided into an outer annulus fibrosus surrounding a centrally located nucleus pulposus. The endplates surround the IVD from both the cranial and caudal ends, and separate them from the vertebral bodies and prevent the highly hydrated nucleus pulposus from bulging into the adjacent vertebrae. The IVD develop from the mesodermal notochord and receive nutrients mostly through the cartilaginous endplates. Physiologically they are innervated only in the outer annulus fibrosus by sensory and sympathetic perivascular nerve fibres, branches from the sinuvertebral nerve, the ventral rami of spinal nerves or from the grey rami communicantes. The IVD undergo changes with ageing and degeneration, the latter having two types i.e. “endplate-driven” involving endplate defects and inward collapse of the annulus fibrosus and “annulus-driven” involving a radial fissure and/or an IVD prolapse. This review summarises and updates the current state of knowledge on the embryology, structure, and biomechanics of the IVD and its endplates. To further translate this into a more clinical context this review also demonstrates the impact of ageing and degeneration on the above properties of both the IVD and its endplates.
A Pixel Vertex Tracker for the TESLA Detector
In order to fully exploit the physics potential of a e+e- linear collider,
such as TESLA, a Vertex Tracker providing high resolution track reconstruction
is required. Hybrid Silicon pixel sensors are an attractive sensor technology
option due to their read-out speed and radiation hardness, favoured in the high
rate TESLA environment, but have been so far limited by the achievable single
point space resolution. A novel layout of pixel detectors with interleaved
cells to improve their spatial resolution is introduced and the results of the
characterisation of a first set of test structures are discussed. In this note,
a conceptual design of the TESLA Vertex Tracker, based on hybrid pixel sensors
is presentedComment: 20 pages, 11 figure
Endplate calcification and cervical intervertebral disc degeneration: the role of endplate marrow contact channel occlusion
Background: The aim of this study was to determine the fundamental relationships between cervical intervertebral disc (IVD) degeneration, endplate calcification, and the patency of endplate marrow contact channels (MCC). Materials and methods: Sixty cervical IVDs were excised from 30 human cadavers. After sectioning the specimens underwent micro computed tomography (microCT) — from all images the number, calibre, diameter and distribution of endplate openings were measured using ImageJ. Next, the specimens were scored for macroscopic degeneration (Thompson’s classification), and subsequently underwent histological analysis for both IVD and endplate degeneration (Boos’s classification) and calcification. Results: The study group comprised 30 female and 30 male IVDs (mean age ± SD: 51.4 ± 19.5). Specimen’s age, macroscopic and microscopic degeneration correlated negatively with the number of MCCs (r = –0.33–(–0.95); p < 0.0001), apart from the MCCs > 300 μm in diameter (r = 0.66–0.79; p < 0.0001). The negative relationship was strongest for the MCCs 10–50 μm in diameter. Conclusions: There is a strong negative correlation between the number of endplate MCCs, and both macroscopic and microscopic cervical IVD and endplate degeneration. This could further support the thesis that endplate calcification, through the occlusion of MCCs, leads to a fall in nutrient transport to the IVD, and subsequently causes its degeneration
Characterisation of Hybrid Pixel Detectors with capacitive charge division
In order to fully exploit the physics potential of the future high energy e+
e- linear collider, a Vertex Tracker providing high resolution track
reconstruction is required. Hybrid pixel sensors are an attractive technology
due to their fast read-out capabilities and radiation hardness. A novel pixel
detector layout with interleaved cells between the readout nodes has been
developed to improve the single point resolution. The results of the
characterisation of the first processed prototypes are reported.Comment: 5 pages, 2 figures, presented at LCWS2000, Linear Collider Workshop,
October 24-28 2000, Fermi National Accelerator Laboratory, Batavia, Illinois,
U.S.A. Proceedings to be published by the American Institute of Physic
Median nerve thenar motor branch anatomical variations
Aim. The aim of this study was to determine the prevalence of the different types of the median nerve thenar motor branch and to compare them with literature data.Materials and Methods. This study has been conducted using median nerves dissected from cadavers stored in a 10% solution of formaldehyde at the Department of Anatomy, Jagiellonian University Medical College (JUMC) and cadavers from the Department of Forensic Medicine (JUMC). The research protocol was approved by the Jagiellonian University Ethics Committee (registry KBET/209/B/2002).Results. The studied group comprised of 8 (26,7%) women and 22 men (age between 23-92 years), yielding a total of 60 thenar motor branches (30 right vs. 30 left). Forty-seven (78,3%) nerves were classified as extraligamentous, 12 (20%) were subligamentous and 1 (1,7%) was transligamentous. As for the side of origin of the thenar motor branch in 45 cases (75%) it was the radial side and in 2 cases (3,33%) it was the ulnar side.Conclusions. The obtained results confirm that the extraligamentous type of the thenar motor branch is the most common and that the ulnar origin of the thenar motor branch is the rarest
Computer-assisted assessment of the histological structure of the human sural nerve
Background: The aim of this study was to assess the histological structure (cross-sectional area — CSA, number of nerve bundles) of the human sural nerve at the level above the lateral malleolus, using computer-assisted image analysis.Materials and methods: This study has been conducted using sural nerves dissected from cadavers during routine autopsies. The harvested tissues samples were dehydrated, embedded in paraffin, sectioned at 4 μm and stained with haematoxylin and eosin. Each cross-section was photographed (16 × magnification) and the images were analysed using Java ImageJ.Results: The studied group comprised 12 women and 25 men (mean age 60.1 ± 15.7 years), yielding a total of 74 sural nerves (37 right vs. 37 left). The mean ± standard deviation CSA of the sural nerve was 0.14 ± 0.07 cm2. The mean number of nerve bundles in the sural nerve was 10.5 ± 6.0. In terms of gender and side, neither the CSA (p = 0.45 and p = 0.79, respectively) nor the number of nerve bundles revealed any differences (p = 0.34 and p = 0.47, respectively). Strong negative correlations were noted between the age of the donors and the sural nerve CSA (r = –0.69,p = 0.02), as well as the number of nerve bundles (r = –0.57, p = 0.06).Conclusions: This study shows that there are no statistical differences between the CSA and the number of nerve bundles in the sural nerve when compared by gender and side of the lower limb. This study also allows drawing the conclusion that the sural nerve degenerates with age in terms of both the CSA and the number of nerve bundles
Anatomic variability of groin innervation
Inguinal hernia repairs are very common yet fairly complex surgical procedures.Variations in the anatomical course of the inguinal nerves require that diligenceis taken in their proper recognition. Inadvertent surgical injury to these nerves isassociated with long term postoperative pain and complications. The aim of thepresent study was to highlight the complexity and variation in the innervation ofthe inguinal region in order to increase proper nerve identification during surgicalinterventions. Bilateral dissection of the inguinal and posterior abdominal regionsin one human male cadaver revealed an atypical anatomic topography of thegroin innervation. This unusual case was observed at the Jagiellonian UniversityAnatomy Department during routine cadaveric preparations. The left ilioinguinalnerve was absent. The left genital branch of the genitofemoral nerve arose higherthan expected from the lumbar plexus and supplied the groin region, which istypically innervated by the ilioinguinal nerve. Furthermore, the left lateral cutaneousfemoral nerve and the right genital branch of the genitofemoral nerve alsofollowed uncharacteristic courses. Awareness of topographical nerve variationsduring inguinal hernia repair will help surgeons identify and preserve importantnerves, thus decreasing the incidence of chronic postoperative pain
The anatomical landmarks effective in the localisation of the median nerve during orthopaedic procedures
Background: The aim of this study was to create a safe zone for surgeons who perform procedures in the wrist to avoid iatrogenic damage to the median nerve (MN) by identifying anatomical landmarks using ultrasound (USG).Materials and methods: We measured the distances between the MN and two easily identifiable anatomical landmarks at the level of the proximal border of carpal ligament using USG.Results: A total of 57 volunteers (n = 114 upper limbs) were included in this study. Our main findings revealed that the distance from the flexor carpi radialis tendon to MN (FCR-MN) was 7.87 mm (95% confidence interval 7.37–8.37) and the distance from flexor carpi ulnaris tendon to MN (FCU-MN) was 19.09 mm (95% confidence interval 18.51–19.67).Conclusions: The tendons of FCR and FCU are easily identifiable landmarks that can be distinguished using simple palpation. Based on our USG findings, the area around FCR should be carefully navigated to avoid iatrogenic injury to the MN during surgical procedures around the carpal tunnel
Vascular architecture of the human uterine cervix, as assessed in light and scanning electron microscopy
Objectives. The aim of this study was to visualize and describe the vasculature of the human uterine cervix.Materials and Methods. The material for this study was obtained from women (age between 20 to 45 years) during autopsy. The material was collected not later than 24 hours post-mortem. This study was performed using uteri from cadavers of menstruating nulliparas (33 uteri) and menstruating multiparas (27 uteri). Collected uteri were perfused via the afferent vessels with Mercox resin (for corrosion-casting and SEM assessment) or acrylic paint solution (light microscopy assessment). The research protocol was approved by the Jagiellonian University Ethics Committee (registry KBET/121/8/2007).Results. In all cases bilateral cervical branches (1-4), originating from the uterine artery, were found. Both in the vaginal and supravaginal parts of the cervix, four distinct vascular zones were found. In the pericanalar zone ran small veins, responsible for draining the mucosal capillaries. Both in the muscular layer, as well as in the pericanalar zone, arterioles and venules passed close to each other, often adjoining.Conclusions. This study does not confirm the existence of a single “cervicovaginal” artery, but shows that the vascular supply of the cervix comes from several vessels. It also introduces the idea of two systems, responsible for draining blood from the mucosal capillaries. Neither assessment in light microscopy nor in SEM has revealed any differences between multiparas and nulliparas, as to the vascular architecture of the cervix
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