123 research outputs found
Anatomy of the posterior cruciate ligament
The purpose of the study was to explain the architecture of the posterior cruciate
ligament because the views on its structure presented in the literature are
inconsistent - from those considering it as indivisible to those presenting it as
a multifascicular structure. Twenty formalin-fixed ligaments from human knee
joints were tested using the preparation technique. All posterior cruciate ligaments
clearly divided into the anterolateral bundle and the posteromedial bundle
(20/20). In all ligaments, 2 fascicles were identified in the posteromedial
bundle (20/20). In most cases, 2 fascicles were also seen in the anterolateral
bundle (14/20). Less commonly, it consisted of multiple fascicles (6/20)
Course variability of the atlantic (V3) segment of vertebral artery: anatomical study with clinical implications
Background: The atlantic segment of vertebral artery (V3) located at the centre of the cranio-vertebral junction is known for its variability and asymmetry, and is either the target or on the way of numerous procedures in this region. The aim of the study was to visualise variability of V3 segment.
Materials and methods: The V3 segment was studied in 49 specimens of the suboccipital region injected with coloured gelatine. Direct measurements were performed and probabilistic maps were created using digital photography.
Results: The V3 segment has wavy course with possible lateral and significant postero-inferior expansions. In relation to the foramen transversarium the V3 reached up to 5 mm laterally, 23 mm posteriorly, 27 mm medially and up to 11 mm downward. Looking from the medial aspect the course of the V3 is less predictable compared to the lateral approach. Linear measurements and probabilistic maps revealed significant variability and large range of variation. There were 11 cases of V3 tortuosity found in studied material.
Conclusions: The complex and variable spatial conformation of V3 makes individual diagnostic and preoperative approach necessary
Anatomy of sartorius muscle
A sartorius muscle is the longest muscle of the human system. It runs over 2 joints— hip and knee joints. In the study 10 sartorius muscles were examined. They were dissected free of lower human limbs. Dimensions of limbs which these muscles come from and dimensions of the muscles and their component parts were examined. The attention was paid mainly to parts of tendon located inside the muscle belly. The results show that they are either of a comparable length (distal tendon) or several times longer (proximal tendon) than visible parts located outside of the muscle. Moreover, a complex structure of the distal tendon which includes 2 tracts of different places of insertion was stated. Inferior tract inserted in the same place as muscle tendons: semitendinosus and gracilis. The superior tract inserted transversely against the former one. The tendon of the sartorius muscle forms additionally an aponeurosis whose fibres enter into the deep fascia of crus. The muscle belly is characterised with various width on different levels of its length. In half of casess word-like distal segment of belly is formed
Controlling charge injection in organic field-effect transistors using self-assembled monolayers
We have studied charge injection across the metal/organic semiconductor
interface in bottom-contact poly(3-hexylthiophene) (P3HT) field-effect
transistors, with Au source and drain electrodes modified by self-assembled
monolayers (SAMs) prior to active polymer deposition. By using the SAM to
engineer the effective Au work function, we markedly affect the charge
injection process. We systematically examine the contact resistivity and
intrinsic channel mobility, and show that chemically increasing the injecting
electrode work function significantly improves hole injection relative to
untreated Au electrodes.Comment: 5 pages, 2 figures. Supplementary information available upon reques
The study of arterial anastomoses in the region of the alveolar process and the anterior maxilla wall in foetuses
The anterior maxilla wall and alveolar process are covered by the arterial network.
Procedures in this region can cause heavy bleeding. Knowledge of the
anatomical course of a particular artery is essential for performing surgery in
this area. The aim of this study was to search for and then analyse anastomoses
between the infraorbital and posterior superior alveolar artery.
In the study, 19 maxillas of foetuses were analysed. The arteries were injected
with coloured latex. The dissection was carried out using a surgical microscope
and microsurgical equipment. The lower eyelid with cheek skin was separated
and the facial muscles were cut to expose the maxilla and arteries of the alveolar
process.
The study revealed that in 10 out of 19 of the specimens there was an arterial
connection between the infraorbital and posterior superior alveolar artery. The
course of the analysed anastomosis was diverse. In all cases we observed an
anterior superior alveolar artery. In all specimens the alveolar process was vascularised
by many arteries originating from the analysed anastomosis.
The location of the analysed anastomosis can be stated before operation, on
the line between the medial eye angle and the sixth tooth of the same side.
The anastomosis described in the study means that caudally running arteries
are important in choosing incisions in procedures performed at the alveolar
process
Image-guided dissection of human white matter tracts as a new method of modern neuroanatomical training
Neuronavigation is a kind of image-guided surgery used during neurosurgical
procedures. Based on specific equipment which is compatible with the software
calculating and processing the patient’s data; this method allows the determination
of the location of anatomical structures and visualisation of surgical instruments
in the operative field. Although standard brain dissection is still the best
method of neuroanatomical training, some limitations occur. The most important
of these is the inability of conversion from three-dimensional (3D) view to
flat pictures of the brain structures, as viewed on computed tomography (CT)
and magnetic resonance imaging (MRI), being essential in neuroanatomical training
nowadays. The aim of the study was the implementation of a neuronavigating
system for brain anatomy training purposes. The study was performed on
10 human brain hemispheres, dissected due to classical methods (standard brain
anatomical sections, stepwise ventricular system opening and partial dissection
of white matter tracts using Klingler’s dissection technique). The material was
scanned in a 1.5 T magnetic resonance scanner using a modified neuronavigation
protocol. The brains were prepared before dissection as proposed by Klingler.
The subsequent steps of the dissection were documented with a digital
camera. The progress of the dissection was visualised using the neuronavigation
system (Medtronic Stealth Station Treon) with cranial application software. In
the course of the study, numerous 3D and 2D images were obtained. The images
were related to each other and linked anatomical structures in the specimen
with their appearance on CT and MRI scans. The implementation of a neuronavigation
system for brain structures dissection facilitates visualization and understanding
of their proper location. This new method offers a constant and precise
orientation and simplifies understanding of the relation of the 3D view of a specimen
to that of the 2D image
The anatomy of the fundic branches of the stomach: preliminary results
The fundic branches of the stomach can be defined as a group of vessels that
can arise either directly or indirectly from the following source arteries: the left
inferior phrenic artery, the accessory left hepatic artery, the left gastric artery,
the left middle suprarenal artery, the main trunk of the splenic artery, the posterior
gastric artery, the superior polar artery, the gastrosplenic artery, the left
gastroepiploic artery and the splenic artery with its inferior and superior terminal
branches. It is worth mentioning that the fundic branches of the left gastroepiploic
artery and the superior and inferior terminal branches of the splenic
artery, like other vessels arising from these three source arteries and supplying
the stomach, are defined as short gastric arteries.
The anatomy of these fundic branches, particularly relevant to some surgical
procedures, is not sufficiently described, and the current literature suffers from
lack of publications on this particular topic. We therefore decided to explore in
detail the arterial vascularisation of the gastric fundus.
The research was carried out on material consisting of 15 human stomach
specimens. The anatomical analysis comprised the following: the number of
occurrences of fundic branches in each of the source arteries defined above,
the distance between the origins of the source artery and its arising fundic
branch, the way in which the fundic branches arose, the length, diameter at
point of origin and morphology of the fundic braches, as well as the exact
point of perforation of each fundic branch on the fundus.
The highest incidence of the direct-branching pattern of fundic branches was
in the left middle suprarenal artery, the gastrosplenic artery and the left gastrosplenic
artery. The accessory left hepatic artery, the left gastric artery and the
main trunk of the splenic artery were the most frequent site of the indirectly
arising pattern of fundic branch. The highest median value of fundic branch
length was 63.05 mm, found in the accessory left hepatic artery group. The
largest median diameter value of the vessel was encountered among those
originating in the left middle suprarenal artery and reached 2.17 mm. The
posterolateral quadrant of the fundus received the largest number of fundic
branches, amounting to 46.5% of all the fundic branches studied. (Folia Morphol
2008; 67: 120–125
Radiological anatomy of the ambient cistern in children
Ambient cistern (AC) is a thin extension of the subarachnoid space surrounding
the brainstem at the level of the mesencephalon and pons. Despite various
definitions, it constitutes an important landmark in clinical assessment of intracranial
volume reserve. Although it is indisputably useful, there exists no
defined standard for radiological examination for the dimensions and ranges
in specific age groups. This paper aims to describe the ambient cistern anatomically
and give the ranges of dimensions for proper radiological interpretation.
The study was performed on 160 axial computed tomography (CT) examinations
of Polish children of both sexes, aged 1-18 years, admitted to the
hospital because of mild brain concussion. Pictures were made using a Siemens
8-row CT scanner, without contrast administration. We estimated distances
at the level of the pons and midbrain, based on axial cross-sections,
according to standard radiological protocol. The parameters included the width
of the AC in its anterior and posterior part, the width of the tentorial notch,
and the distance from the pons and sella. All measurements were analyzed
statistically with StatSoft Statistica 8.0 software. The average width of the AC
differs between age groups. It is greatest at 1-3 years (2.8 ± 0.6 mm) and
lowest at 4-10 years (2.4 ± 0.6 mm). AC is more likely to be greater in its
anterior part in boys. The distance from the sella to the pons is greatest in 1-3-year-old girls (6.9 ± 1.3 mm), and the tentorial notch is widest in the 15-18-year-old group (24.6 ± 2.4 mm). Dimensions of the AC correlate with intracranial
reserve volume. This is particularly visible in the youngest children. Thin
and narrow AC is not always a sign of raised intracranial pressure. It may be
specific for the child’s age. (Folia Morphol 2010; 69, 2: 78-83
Diversity of coronary arterial tree in laboratory mice
Background: Research on the development and topography of mouse coronary arteries has been conducted for many years. Patterns of the course of these vessels have been described in various mouse strains. Our research focused on hearts of MIZZ mice.
Materials and methods: We visualised the coronary artery system by means of latex dye perfusion via the aorta. The injected latex did not reach the capillary vessel system.
Results: The heart of MIZZ mice is supplied with blood by two main coronary arteries: the right and the left one. They deliver blood to the right and left part of the heart, respectively. The right coronary artery arises from the right sinus of the aorta and the left coronary artery from the left sinus. The interventricular septum is usually supplied by the septal artery, which is the main branch of the right coronary artery. All arteries of the coronary system run intramurally. The number of branches and the location of their ostia differed among the examined individuals.
Conclusions: Detailed information about the normal topography of coronary arteries, the number and course of their branches, as well as the area of the heart which is vascularised by these vessels constitutes the basic knowledge necessary to conduct further experiments
Median aperture of the fourth ventricle revisited
Background: The median aperture of Magendie is the largest of three openings
of the fourth ventricle and thus it forms the main path for the outflow of
the cerebrospinal fluid from the ventricle. The Magendie aperture connects the
fourth ventricle with the cisterna magna and makes a natural corridor for neurosurgical
approach and inspection of the ventricle and its floor. The purpose
of this study was to give a contemporary anatomical view of this structure in
the context of historical data.
Material and methods: The Magendie foramen was studied in 30 fixed specimens
of human brainstems with cerebella. The microdissection technique
was used. Measurements were taken with a microscope ocular ruler.
Results: The aperture is limited by the following structures: obex and gracile
tubercles inferiorly, and tela choroidea with choroid plexus superolaterally. Obex
tubercles usually have the form of a piece of neural tissue bridging two halves
of the brainstem above the entrance to the central canal. Gracile tubercles
together are 8.15 mm wide and the maximal width of the foramen is 6.53 mm.
Tela choroidea attaches laterally at both sides to the inferior medullary velum.
In most cases the right and left choroid plexus are connected to each other
with a triangular membrane of tela choroidea, which protrudes through the
median foramen and attaches to the vermis at a highly variable level.
Conclusions: We hope that the presented description of anatomical relations
around the Magendie aperture, with its new measurements, will be helpful for
those operating in the area and will explain some of the inaccuracies found in
literature. (Folia Morphol 2011; 70, 2: 84–90
- …