Search PubMed⌕ Search

Biomedical subjects

S Anagnostopoulou

Publications and source records attributed to S Anagnostopoulou.

At least 19 recordsLinked to original sources

Thecaloscopy through sacral bone approaches, cadaver study: further anatomic landmarks.

Endoscopy of the spinal canal, for interventional studies, diagnosis and therapy, is a scientific topic that has attracted the interest of neurosurgeons, anesthesiologists and orthopedic surgeons for the past twenty years. Endoscopy of the thecal sac was assumed to be less important than endoscopy of the ventricular system by neurosurgeons. Nevertheless, during the last years it has attained increasing scientific interest, firstly because of the introduction of small diameter flexible endoscopes and secondly due to the growing interest for minimal invasive diagnostic and therapeutic procedures in modern neurosurgery. Until now thecaloscopy was performed by the ISGT (International Study Group for Thecaloscopy) using co-axial downward orientated approaches. We have examined transsacral approaches to facilitate the navigation of flexible scopes in the lumbosacral subarachnoid space, and thus we now introduce further recognizable endoscopic anatomic landmarks.

Adult↗

The development of the spiral ganglion in the human foetus.

The development of the spiral ganglion was studied in steps sections of 81 human temporal bones. By the 8th week, the spiral ganglion has already separated from the vestibular ganglion. At 13 weeks two distinct populations are observed that correspond to neuron and Schwann cells. At 15 weeks the spiral ganglion has increased its distance from the cochlear duct and is surrounded by mesenchyme near the scala tympani. At 14 weeks a gradual decrease in the nucleus-to-cell area ratio was observed in spiral ganglion neurons that may reflect a morphological adaptation to function. By the 23rd week the modiolus begins to ossify and the spiral ganglion is surrounded by bony trabeculae. The time course of spiral ganglion development follows that of the stria vascularis and organ of Corti, although maturation changes are still observed in the neuronal population even beyond 20 weeks.

Cell Nucleus↗

Ketamine-induced changes in metabolic and endocrine parameters of normal and 2-kidney 1-clip rats.

BACKGROUND AND OBJECTIVE: The aim of this study was to investigate the effect of ketamine on the endocrine and lipid metabolic status of the renal-banded animals. METHODS: Forty male rats were randomly divided into four groups. Group A served as control, Group B animals received ketamine intraperitoneally at a dose of 100 mg kg(-1), Group C was submitted to 2-kidney 1-clip experimental hypertension and Group D received ketamine as above, as well as being submitted to renal artery clipping. Atrial natriuretic peptide, angiotensin II and free fatty acid concentrations were measured in serum. In addition, adipose tissue lipoprotein lipase activity and angiotensin II content were determined, while the left ventricular weight relative to body weight was used as a cardiac hypertrophy index. RESULTS: In renal-banded rats (Groups C and D) serum atrial natriuretic peptide, free fatty acid and angiotensin II concentrations as well as ventricular weight were increased, while adipose tissue lipoprotein lipase activity was lower than in control animals (Groups A and B). Ketamine administration did not influence angiotensin II concentrations either in normal (Group B) or banded rats (Group D). Ketamine increased serum atrial natriuretic peptide and free fatty acid concentrations only in normal animals (Group B). It had no influence on adipose tissue lipoprotein lipase activity either in normal (Group B) or banded animals (Group D). Adipose angiotensin II content did not differ between the four groups. CONCLUSION: Ketamine increased the atrial natriuretic peptide and free fatty acid concentration in normal rats. In 2-kidney 1-clip animals, ketamine did not elicit an additional response of serum atrial natriuretic peptide or free fatty acids levels. Its contribution to these factors was not significant.

Adipose Tissue↗

Angioplasty and stenting of extracranial vertebral artery stenosis.

Percutaneous angioplasty and stent placement seem a useful technique for the treatment of vertebro-basilar insufficiency and the first treatment to be proposed. This technique appears safe and effective for alleviating symptoms and improving blood flow to the cerebral circulation, with a low complications rate and good long-term results. However, this procedure needs experienced interventionists to choose the stent and have appropriate placement of the stent in the ostium of the vertebral artery (VA). The tortuosity of the VA may be technically challenging. The new coronary stents seem to be well suited to treat atherosclerotic lesions of the origin and of the proximal VA. A large variability of restenosis risk has been reported. Drug eluting stents may be the solution. Prospective randomized studies are needed to demonstrate the clinical effectiveness of VA stenting in stroke prevention, its durability, and to define more clearly its indications.

Angiography↗

A new morphometric method for the sella turcica and the hypophyseal fossa and its clinical relevance.

The sella turcica and the hypophyseal fossa should be considered different entities, the latter being part of the former. Their morphology and dimensions correlate to some extent with those of the contained pituitary gland and have, for this reason, attracted the interest of anatomists and radiologists. With the application of MRI, however, these data are of limited use in the diagnosis of pituitary disorders, although they remain valuable with regard to a microsurgical approach to the hypophysis. The proposed morphometric method was applied to 20 dry skulls. We first made casts of the corresponding sellae. Their volumes were then measured by immersion. The frontal section of each hypophyseal fossa was obtained through its deepest point and magnified. The Cartesian co-ordinates of the contour of the section were used to evaluate the corresponding area and centroid. The volume of each fossa was finally obtained by the use of Pappus' theorem applied to solids of rotation. The volumes of the sellae obtained as above ranged from 460 mm3 to 1570 mm3 with a mean value of 835 mm3. These figures are comparable to those reported from previous authors. To our knowledge the method described has enabled a close approximation of the volumes of the hypophyseal fossae to be made for the first time. These volumes ranged from 24 mm3 to 300 mm3, with a mean value of 157 mm3. Similar numerical methods might be applicable in vivo by the use of MR imaging.

Anthropometry↗

Topographic relationship between the cochlea and the middle fossa floor: the anatomical basis for an alternative approach to the cochlear turns.

The cochlea has attained extreme surgical interest since cochlear implantation has been recognized as an established method for the management of certain types of bilateral profound hearing loss. Traditionally access to the cochlear turns is achieved through the middle ear. Extremely limited references exist in the literature regarding alternative surgical approaches to the cochlea. In the present study we tried to highlight the anatomic relationships of the superior aspect of the bony cochlea to the adjacent superficial structures of the petrous bone, as there have been suggestions that the cochlea is surgically accessible through the floor of the middle cranial fossa (MCF). A total of 58 dry human adult skulls (116 temporal bones) were studied. The groove for the greater superficial petrosal nerve (GGSPN) and the facial hiatus were used as landmarks in order to expose the superior aspect of the cochlea. Measurements were made of the following distances: a) between the MCF floor and the superficial part of the basal turn (SPBT), b) between the MCF floor and the apex of the cochlea, c) between the SPBT and the GGSPN and d) between the SPBT medially and the first genu of the facial canal laterally. Our results indicate that adequate and reliable surgical access to the bony cochlea could be achieved through the MCF floor.

Cadaver↗

A regulated telemedicine system for day to day application in remote areas.

The NIVEMES project creates an international network of Health Service providers which offer Telemedicine-Teleconsultation services to Remote, Isolated places and to ship vessels for both routine and emergency situations. The base of the system is the powerful Multimedia Health Record, with the ability to manage conventional data, images, videos and biosignals, acquired directly from the medical device. National and international medical codification schemata are employed such as ICD-X and WHO standards. Telemedicine and Computing in Health Care are rapidly covering a pending gap, not fulfilled by current bureaucratic and telematic procedures. However even from the first test fields conducted during the past year, it is obvious that a variety of new training needs has arisen. The users of such systems need to be instructed new ways of conducting their business, of taking advantage of the services, even a new way of perceiving health care provision. The user interface of the software is kept simple, thus getting acquainted with it requires minimum effort; however there are other issues on which training is required to best exploit the advantages the system offers. The telemedical networks spawned in each country must be co-ordinated, and the user needs to know where and how he/she will acquire the necessary support. Home-cared patients will have to operate medical devices and telemedical software, a task which although made easy from today's technology, it still requires some basic training, specially as far as elderly users are concerned. The NIVEMES system uncovers a set of new training needs, but it offers at the same time a vehicle for educating the professional health-carers. The Health Record comprises a multimedia, explicit account of the patient history, which can be used for detailed and integrated study from trainee health carers of all levels (as well as from officers on board, people taking care of home-confined patients and others), on real data or in a simulated environment. At the same time the telemedicine facilities may increase the effectiveness of junior doctors working in remote areas and enhance the confidence residents have about their local health centres. Systems like NIVEMES prove that new user needs arise nowadays and employment of modern tools requires training in modern methods and in a new way of thinking.

Europe↗

Classification of communications between the musculocutaneous and median nerves.

In 16 out of 79 cadavers 22 communications were found between the musculocutaneous and median nerves. In six subjects they were present bilaterally. There were three types, based on the sites of communication. Type I: The communication was proximal to the entrance of the musculocutaneous nerve into coracobrachialis (9/22); Type II: The communication was distal to the muscle (10/22); Type III: The nerve as well as the communicating branch did not pierce the muscle (3/22). Bilateral communications were not necessarily of the same type. The possible clinical implications of these communications (relating either to the surgical approach to the shoulder joint, or to entrapment syndromes) are discussed.

Brachial Plexus↗

Classification of human maxillar sinuses according to their geometric features.

119 casts of maxillary sinuses have been taken out of 60 dry skulls. In these specimens, the volume V, the area of the basal (i.e. corresponding to the nasal cavity) surface S and the height h have been measured. The sinuses are subsequently arranged into 4 classes, according to their similarity to solids of revolution such as: semi-ellipsoid (class a: 15% of specimens); paraboloid (class b: 30%); hyperboloid (class c: 47%) and cone (class d: 8%). As criterion for this classification, the value of the coefficient K, equal to v/Sh has served. Beyond the eventual anatomical and anthropological interest of this classification, a clinical interest may exist in combination with Computed Tomography or eventually with Echography. The asymmetry that exists between maxillary sinuses (56% of our sample comprises pairs of sinuses arranged in different classes) suggests the eventual necessity of separate radiography of each individual sinus.

Algorithms↗

[The infraorbital foramen (the position of the infraorbital foramen in man)].

The injection of the infraorbital nerve in the infraorbital canal, gives a full anesthesia to the anterior superior nerve, for a major operations in the anterior part of the upper jaw or in case which an infection precludes a local injection. In this study we describe in detail the position of the infraorbital foramen in 55 crania and in 16 cadavers. As landmarks in the cadavers, we used the lateral point of the wing of the nose, and the medial angulus oculi. As landmarks in the crania we used, the inferior orbital rim, the zygomaticoalveolar crest and the anterior nasal spine. The results of our measurements are the following: 1. The infraorbital foramen is situated in equal distance from the medial angulus oculi and the zygomaticoalbeolar crest. 2. The infraorbital foramen, the anterior nasal spine and the zygomaticoalveolar crest form the vertex of an isosceles triangle. The infraorbital foramen is situated in the vertex which corresponds to the one of the equal angles. 3. The infraorbital foramen is situated 7.19 mm below the infraorbital.

Humans↗

[Anatomical and radiographic study of the sinus floor distance from the alveolar crest in edentulous area of skulls].

The distance between the floor of the maxillary sinus and the alveolar crest in edentulous areas (where the 2nd bicuspid 1st and 2nd molars were previously located) were studied both anatomically and radiographically. The material consisted of 22 skulls in which 33 edentulous maxillary areas were found. Direct anatomical measurements were performed and measurements on periapical radiographs were made. The most important findings can be summarized as follows: 1. The mean distance from the alveolar crest to the floor of the sinus in locations corresponding to the 1st and 2nd molars and the 2nd bicuspid was 5.09 mm, 5.16 m.m. and 6.67 m.m. respectively. 2. Comparison of the anatomical measurements to those made on the radiographs proved that there are some differences but not statistically significant. These differences range between 0 to 5.5 m.m. for the 2nd bicuspid location, while for the 1st and 2nd molar locations they range between 0 to 2 mm.

Alveolar Process↗