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1.
Science ; 258(5081): 455-7, 1992 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-1411539

RESUMEN

The corpse of a Late Neolithic individual found in a glacier in Oetztal is unusual because of the intact nature of all body parts that resulted from the characteristics of its mummification process and its protected geographical position with regard to glacier flow. Anthropological data indicate that the man was 25 to 40 years old, was between 156 and 160 centimeters in stature, had a cranial capacity of between 1500 and 1560 cubic centimeters, and likely died of exhaustion.


Asunto(s)
Hominidae/anatomía & histología , Momias , Animales , Austria , Oído/anatomía & histología , Congelación , Historia Antigua , Humanos , Italia , Masculino , Cráneo/anatomía & histología
2.
Bone ; 15(4): 387-91, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7917576

RESUMEN

Reduced bone mineral density (BMD) increases risk of fractures, thus making it necessary to monitor patients suffering from chronic renal failure and consecutive disturbance of bone metabolism. In order to evaluate the reliability of available methods, bone mineral density of the lumbar spine assessed with single energy computed tomography (QCT) was compared with bone mineral density of the lumbar spine, femoral neck, Ward's triangle and trochanteric region measured by dual energy photon absorptiometry (DPA) in 45 hemodialyzed patients with a mean hemodialysis duration of 35 +/- 26 months (SD). Depending on the measurement site and method 4-34% of dialyzed patients suffered from reduced BMD (z-score < -2). The highest correlation (r = 0.61, p < 0.01) was found between QCT of the spine, trabecular bone, and DPA of Ward's triangle. One year after baseline measurement bone mineral density was reassessed after randomization to either QCT or DPA in 14 and 18 patients, respectively. Whereas lumbar spine and femoral neck did not change, mean BMD showed a decrease at the measurement sites of Ward's triangle (DPA), trochanteric region (DPA) and trabecular bone of the spine (QCT), which, however, was statistically not significant. Cortical BMD of the spine assessed with QCT showed an increase. Although there is some reduction in bone density at most sites in hemodialyzed patients, no significant bone loss could be demonstrated over the course of 1 year.


Asunto(s)
Absorciometría de Fotón/métodos , Densidad Ósea/fisiología , Fallo Renal Crónico/terapia , Diálisis Renal , Tomografía Computarizada de Emisión de Fotón Único/métodos , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Calcio/sangre , Nefropatías Diabéticas/metabolismo , Nefropatías Diabéticas/terapia , Femenino , Cuello Femoral/patología , Cuello Femoral/fisiología , Estudios de Seguimiento , Fracturas Óseas/etiología , Humanos , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/metabolismo , Vértebras Lumbares/patología , Vértebras Lumbares/fisiología , Masculino , Persona de Mediana Edad , Radioinmunoensayo , Distribución Aleatoria , Factores de Riesgo
3.
Int J Radiat Oncol Biol Phys ; 48(1): 147-51, 2000 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-10924984

RESUMEN

PURPOSE: In prophylactic irradiation of infradiaphragmatic lymphatic nodes (LN), the width of the paraaortic and pelvic field is given by a line joining the tips of the transverse processes of the 11th thoracic to the 4th lumbar vertebrae. Then the field boundary follows a straight line to the most lateral point of the acetabulum seen on the simulation film. Another method of setting the field border is to project the lateral contours of the large abdominal vessels from T(1)-weighted coronal MR images of the abdomen onto the simulator radiographs and add a 2-cm margin along the so delineated vessels. In our study, we compared both methods as to full enclosure of paraaortic and pelvic lymphatics or nodal miss. MATERIAL AND METHODS: Abdominal CT scans of 81 patients with involvement of paraaortic lymph node regions with LN sizes not exceeding 2.5 cm were examined. The distance from the center of the appropriate vertebra to the center of the most lateral lymph node was referred to the transverse process as well as to the outside contour of the aorta on the left and the vena cava on the right side. Respectively, the LN were measured referenced to the iliac vessels from the 5th lumbar through to the 2nd sacral vertebra. At the level of the hip joint the distance was measured from the midline as determined by a line through the center of the sacrum, perpendicular to a line connecting center of both femoral heads. RESULTS: Our measurements showed that lymph nodes do occur (1) lateral to the transverse processes of the thoracic and lumbar vertebrae as well as (2) outside the 2-cm safety margin from the lateral contour of the large abdominal vessels. CONCLUSION: These data clearly show that the traditional fields for radiation of infradiaphragmatic lymphatic nodes have not been large enough to enclose almost all retroperitoneal and pelvic lymph nodes with certainty. We recommend an expansion of the fields.


Asunto(s)
Irradiación Linfática/métodos , Linfoma/radioterapia , Aorta Abdominal , Enfermedad de Hodgkin/diagnóstico por imagen , Enfermedad de Hodgkin/radioterapia , Humanos , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/patología , Linfoma/diagnóstico por imagen , Linfoma de Células B/diagnóstico por imagen , Linfoma de Células B/radioterapia , Linfoma no Hodgkin/diagnóstico por imagen , Linfoma no Hodgkin/radioterapia , Persona de Mediana Edad , Radioterapia Adyuvante , Espacio Retroperitoneal/diagnóstico por imagen , Tomografía Computarizada por Rayos X
4.
Eur J Radiol ; 8(1): 6-12, 1988 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3356198

RESUMEN

Preoperative planning of recurrent shoulder dislocation requires an accurate knowledge of bone and soft tissue lesions affecting the joint. A new method of double-contrast CT examination is presented which allows an accurate evaluation of the soft tissue structures important for the stability of the joint. Forty-two patients were examined with this technique, twenty-seven of whom (28 shoulders) were operated on, the procedure being selected on the basis of the CT findings. In all cases the preoperative CT findings corresponded to the intraoperative findings.


Asunto(s)
Luxación del Hombro/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Medios de Contraste , Humanos , Neumorradiografía , Cuidados Preoperatorios , Hombro/diagnóstico por imagen , Luxación del Hombro/cirugía
5.
Eur J Radiol ; 31(2): 88-96, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10565508

RESUMEN

Since the discovery of the Tyrolean Iceman in 1991 advanced imaging and post processing techniques were successfully applied in anthropology. Specific techniques include spiral computed tomography and 3-dimensional reconstructions including stereolithographic and fused deposition modeling of volume data sets. The Iceman's skull was the first to be reproduced using stereolithography, before this method was successfully applied in preoperative planning. With the advent of high-end graphics workstations and biomedical image processing software packages, 3-dimensional reconstructions were established as a routine tool for analyzing volume data sets. These techniques opened totally new insights in the field of physical anthropology. Computed tomography became the ideal research tool to access the internal structures of various precious fossils without damaging or even touching them. Many of the most precious specimens from the species Autralopithecus (1.8-3.5 Myears), Homo heidelbergensis (200-600 kyears) or Homo neanderthalensis (40-100 kyears) were scanned during the last 5 years. Often the fossils are filled with a stone matrix or other materials. During the postprocessing routines highly advanced algorithms were used to remove virtually these incrustations. Thus it was possible to visualize the morphological structures that lie beneath the matrix. Some specimen were partially destroyed, so the missing parts were reconstructed on computer screen in order to get estimations of the brain volume and endocranial morphology, both major fields of interest in physical anthropology. Moreover the computerized form of the data allows new descriptions of morphologic structures by the means of 'geometric morphometrics'. Some of the results may change aspects and interpretations in human evolution. The introduction of new imaging and post processing techniques created a new field of research: Virtual Anthropology.


Asunto(s)
Momias , Algoritmos , Animales , Gráficos por Computador , Historia Antigua , Hominidae/anatomía & histología , Humanos , Procesamiento de Imagen Asistido por Computador , Tomografía Computarizada por Rayos X , Interfaz Usuario-Computador
6.
Am J Sports Med ; 27(6): 733-7, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10569358

RESUMEN

Dynamic high-resolution ultrasonography findings obtained in 34 extreme rock climbers with finger injuries were compared with those in 20 healthy volunteers. Thicknesses of the flexor tendon and A-2 flexor tendon pulley system were measured at the base of the proximal phalanx. The distance between the tendon and phalanx was evaluated with the finger in extension and in forced flexion as a measure of bowstringing. Gliding ability of the flexor tendons was assessed during active and passive motion. Compared with healthy volunteers, climbers showed a significantly increased thickness of the flexor tendons and the flexor tendon pulley system but no impairment of the gliding mechanism. Only in climbers did the distance between tendon and phalanx increase from 0.14 cm (+/-0.07) during extension to 0.30 cm (+/-0.09) during forced flexion. In three climbers with complete A-2 pulley ruptures this distance was up to 0.51 cm (+/-0.15) during forced flexion. Clinically unsuspected synovial cysts, thickened joint capsules, fibrous tissue, or fluid collection were found only in climbers. We concluded that dynamic ultrasonography is a valuable tool for accurate assessment of early changes in "climber's finger." It provides useful information, especially in cases where clinical evaluation is difficult, and should be performed to select appropriate therapeutic management.


Asunto(s)
Traumatismos de los Dedos/diagnóstico por imagen , Montañismo/lesiones , Tendones/diagnóstico por imagen , Adulto , Femenino , Traumatismos de los Dedos/diagnóstico , Traumatismos de los Dedos/etiología , Humanos , Masculino , Persona de Mediana Edad , Rotura , Traumatismos de los Tendones , Tendones/patología , Ultrasonografía
7.
Rofo ; 142(4): 406-10, 1985 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-2986217

RESUMEN

In 100 consecutively operated patients with 167 aortocoronary bypass grafts (ACVB) routine catheterisation was performed three month postoperatively, as well as sequential, ECG-gated and dynamic computed tomography (CT) the day before angiography. The results showed a sensitivity of 92%, a specificity of 67% and an overall accuracy in 81% for CT. Serial (dynamic) CT provides for quantitative assessment of attenuation values of contrast medium enhancement in ACVB and aorta, which improves security of the CT-test in most patients with patent grafts. Therefore clinical contribution of CT will be greatest for routine screening post-operatively and for assessment of ACVB--patency in asymptomatic patients.


Asunto(s)
Angiografía , Puente de Arteria Coronaria , Tomografía Computarizada por Rayos X , Absorciometría de Fotón , Adulto , Electrocardiografía , Estudios de Evaluación como Asunto , Reacciones Falso Positivas , Femenino , Estudios de Seguimiento , Oclusión de Injerto Vascular/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Periodo Posoperatorio
8.
Rofo ; 151(3): 278-83, 1989 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-2552518

RESUMEN

In 26 patients with 35 aortocoronary venous bypass grafts (ACVB) quantitative invasive angiographic parameters were compared with flow parameters of contrast medium, assessed by computed tomography. Out of seven different CT-parameters, the maximum decrease of concentration of contrast medium (40 +/- 5 HE/sec; mean +/- SEM) showed a correlation with the angiographic parameter of contrast medium quantitative flow rate (7.2 +/- 0.5 cm/sec) and this correlation (r = 0.536/SEE = 23.17) is significant (p less than 0.001). We conclude that for the single patient assessment of quantitative flow in ACVB by CT with a 3-second repetition rate could be performed with limited accuracy.


Asunto(s)
Puente de Arteria Coronaria , Oclusión de Injerto Vascular/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Angiografía/métodos , Velocidad del Flujo Sanguíneo , Humanos , Yohexol , Ácido Yoxáglico , Periodo Posoperatorio , Factores de Tiempo , Tomografía Computarizada por Rayos X/métodos
9.
Rofo ; 151(3): 298-300, 1989 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-2552521

RESUMEN

The article reports on 18 sonographically examined patients with clinically verified Peyronie's disease (induratio penis plastica) who underwent a basic sonographical classification according to the system of Kelami. Four weeds after the initial sonography a control study was carried out in 17 patients. 10 of these received a treatment by local instillation with Ontosein, whereas seven patients remained without treatment. In one patient an operation (Nesbit) had been performed in the meantime. 10 of the 17 examined patients presented a change of the initial findings. Seven patients out of the number of the patients who had received treatment presented a change, whereas three patients showed no change of their basic findings. The untreated group of seven patients demonstrated in three cases a change of the sonographic pattern, and four cases were unchanged. The most significant change of the sonographic appearance (treated or untreated) was an increased echogenicity of the corpora cavernosa. In some cases no plaques could be found, in one cases a new plaque developed. In two cases the initial hypoechogenic rings sign disappeared. Sonography, however, cannot prove the success of a specific therapeutic regimen, because 50% of all patients recover without treatment.


Asunto(s)
Induración Peniana/diagnóstico , Pene/patología , Ultrasonografía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Seguimiento , Humanos , Masculino , Metaloproteínas/uso terapéutico , Persona de Mediana Edad , Induración Peniana/tratamiento farmacológico , Superóxido Dismutasa/uso terapéutico , Ultrasonografía/instrumentación , Ultrasonografía/métodos
10.
Rofo ; 154(3): 306-9, 1991 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-1849300

RESUMEN

In a follow-up study of 20 patients with a total of 52 aortocoronary venous bypass grafts (ACVB) three months after surgery, the patency of the grafts was assessed by magnetic resonance tomography (MR) followed by contrast enhanced CT-scan and selective coronary angiography on the following day. Each examination was interpreted independently and immediately after the procedure for the visibility and patency of the grafts. The statistical figures for the non-occluded grafts showed a sensitivity of 90.24% and a specificity of 54.54% for the CT scans and a sensitivity of 73.17% with a specificity of 72.72% for the MR. Although the sensitivity of the CT is somewhat higher than that of MR, neither procedure offers a clear advantage over each other and neither of both methods alone is adequate for the assessment of ACVB's. They are therefore only valuable as an adjunct to clinical data and as a screening procedure for selective coronary angiography.


Asunto(s)
Puente de Arteria Coronaria , Oclusión de Injerto Vascular/diagnóstico , Angiografía Coronaria , Estudios de Evaluación como Asunto , Estudios de Seguimiento , Oclusión de Injerto Vascular/diagnóstico por imagen , Oclusión de Injerto Vascular/epidemiología , Humanos , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos X
11.
Rofo ; 145(5): 586-90, 1986 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-3024259

RESUMEN

The changes of the early intraspinal conditions few days after an operation of a lumbar disc herniation are little known. We, therefore, examined these operation areas by CT on a representative group of 256 patients. Besides the "common" findings, such as seroma, one must classify conditions such as haematomas, isolated bone fragments and/or residual disc tissue as "unusual" changes. The CT findings are correlated with clinical symptoms. We conducted CT and clinical follow-up studies in 91 patients several weeks later. All patients showed epidural scars of very different intensity. The comparison between early postoperative findings and the controls documents the high accuracy of the interpretation of the early postoperative states seen by CT. Therefore, it is possible to give hints for the indication for early postoperative CT examinations, for the prognosis as well as for the technique for a safe operative procedure.


Asunto(s)
Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Femenino , Estudios de Seguimiento , Humanos , Desplazamiento del Disco Intervertebral/cirugía , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Masculino , Complicaciones Posoperatorias/diagnóstico por imagen , Pronóstico , Factores de Tiempo
12.
J Pharm Biomed Anal ; 7(2): 147-54, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2488615

RESUMEN

There are four general assay methods used to quantify a drug/biologic in a preparation, including: (1) in vivo bioassays; (2) in vitro bioassays; (3) immunoassays; and (4) receptor assays. The cell receptor assay is used to evaluate the first step in the molecular action of the drug biologic, its interaction with a specific cellular receptor. Subsequently, the drug biologic must initiate other events, such as internalisation, signal transduction, and/or alterations of one or more cellular constituents in order to elicit its biological effect. Major factors to consider in cell receptor assay development include: (1) establishment of a reference standard preparation; (2) labelling; purifying and characterisation of the biologic drug; (3) cell receptor source; (4) methodology, e.g. separation of bound and free, and other factors affecting accuracy and reproducibility; (5) ligand specificity; and (6) correlation with bioactivity. It should be emphasised that cell receptor binding cannot be assumed to correlate with biological activity because of the requirement that subsequent steps must take place prior to achieving the final response. Chemically altered drugs biologics may bind to a specific cell receptor without eliciting a biological activity. Thus, utilisation of a cell receptor assay requires careful evaluation at both the chemical and biological levels prior to its acceptance as a measure of potency.


Asunto(s)
Bioensayo , Receptores de Droga/efectos de los fármacos , Animales , Células Cultivadas , Humanos
13.
Urologe A ; 27(1): 54-7, 1988 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-3284146

RESUMEN

Malacoplakia is a granulomatous disease that most frequently involves the genitourinary tract. Because of the great variability of symptoms and lack of typical radiologic findings, this disease is usually not considered preoperatively. Generally of benign nature in the lower urinary tract, it leads to destruction and loss of renal function when affecting ureter and kidney. Progression of the latter can only be prevented by surgical intervention. Malacoplakia of the lower urinary tract requires long-term treatment with intracellularly active antibiotics in combination with drugs enhancing phagocytosis.


Asunto(s)
Enfermedades Renales/patología , Malacoplasia/patología , Femenino , Humanos , Riñón/patología , Persona de Mediana Edad , Tomografía Computarizada por Rayos X , Ultrasonografía , Urografía
14.
J Telemed Telecare ; 6 Suppl 1: S160-1, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10794006

RESUMEN

We assessed a data security system using biometric fingerprint techniques and smartcards to control access to a teleradiology system. Clinical cases were initially discussed between the referring physician and radiologist in Tyrol using a video-phone. Subsequent correspondence, including the transmission of images between the referring physician and the radiologist, was carried out by e-mail using the security system to prevent unauthorized access to patient information. Seventy-eight teleradiology sessions were conducted using this data security system. Speed and stability of data exchange were unaffected by the additional security feature. The average log-on time to the system was 7.8 s. The average training time on how to use the system was 15 min. The radiologist was able to issue a final patient report using the system within 1.5 of the initial contact. The data security feature was user-friendly and did not hinder the normal teleradiology consultation.


Asunto(s)
Seguridad Computacional/normas , Telerradiología/normas , Austria , Humanos , Sistemas de Registros Médicos Computarizados
15.
J Telemed Telecare ; 9 Suppl 1: S48-50, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12952721

RESUMEN

The Tyrolean telemedicine pilot project linked the University Clinic of Innsbruck and the district hospital in Reutte. Five medical specialties were investigated: teleradiology, telepathology, teledermatology, tele-ophthalmology and tele-oncology. A Tyrolean 'four-column model of quality management in telemedicine' was introduced to ensure a global view of the project and to avoid mistakes. In teleradiology, a 12-step workflow was developed, which described the medical responsibilities at each stage. We found that the defined teleradiology workflow and the technical equipment for data security and data exchange worked without problems in over 79% of a total of 424 cases. To ensure continuous quality assurance, the whole teleradiology workflow was ISO 9001:2000 certified.


Asunto(s)
Guías de Práctica Clínica como Asunto/normas , Telerradiología/normas , Austria , Humanos , Proyectos Piloto , Garantía de la Calidad de Atención de Salud , Telerradiología/organización & administración
16.
J Telemed Telecare ; 6(1): 27-30, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10824387

RESUMEN

We assessed Websites for radiological education. Of several hundred sites identified, 30 were randomly selected for evaluation by two groups of observers. All Web pages were rated with respect to time required to access the information; structure and organization of the site; image quality; and information content and relevancy. Rapid access was gained to many educational radiology Websites, which contained large numbers of interesting radiological images of good quality. A weak point was the structure and organization of the sites. The greatest variability in ratings was found in the information content and relevancy of the Websites.


Asunto(s)
Internet/normas , Radiología/educación , Telerradiología/normas , Estudios de Evaluación como Asunto , Humanos
17.
J Telemed Telecare ; 9 Suppl 2: S61-2, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14728764

RESUMEN

To guarantee the quality of teleradiology services in Austria we have developed an easy-to-use and continuously re-evaluated teleradiology workflow model. This is based on the quality management model (ISO 9001:2000) of the International Standardization Organization (ISO) and guarantees the quality of the process. From January 2002 to January 2003 we examined 544 emergency teleradiology computerized tomography studies transmitted to the Department of Radiology 2 in Innsbruck. The patients were from the rural hospital of Reutte. In 450 cases (83%) the sending of the written legal final report took less than 1 h. The numbers of mistakes (mostly minor workflow errors) were reduced from 23 errors per month in January 2002 to 9 errors per month in January 2003. The continuous cross-checking of the workflow and the training of the employees involved guaranteed a better standard of teleradiology in our department. Since December 2002, the whole Tyrolean teleradiology process has been ISO 9001:2000 certified.


Asunto(s)
Atención a la Salud/normas , Garantía de la Calidad de Atención de Salud/métodos , Telerradiología/normas , Austria , Atención a la Salud/organización & administración , Servicio de Urgencia en Hospital/organización & administración , Servicio de Urgencia en Hospital/normas , Humanos , Estándares de Referencia , Telerradiología/organización & administración
18.
Coll Antropol ; 23(2): 473-82, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10646222

RESUMEN

In this project we evaluate the dynamic changes during expiration at different levels of positive-end-expiratory pressure (PEEP) in ventilated patients. We wanted to discriminate between normal lung function and acute respiratory distress syndrome (ARDS). After approval by the local Ethic Committee we studied two ventilated patients: (one with normal lung function and one with ARDS) We used the 50 ms scan mode of the EBCT. The beam was positioned 1 cm above the diaphragm while the table position remained unchanged. We developed an electronic trigger that utilizes the respirator's synchronizing signal to start the EBCT at the onset of expiration. During controlled mechanical expiration at two levels of PEEP (0 and 15 cm H2O), pulmonary aeration was rated as: well-aerated (-900HU to -500HU), poorly aerated (-500HU to -100HU) and non-aerated (-100HU to +100HU). Pathological and normal lung functions showed different dynamic changes. The different PEEP levels resulted in a significant change of pulmonary aeration in the same patient. Although we studied only two patients, respiratory triggered EBCT may be accurate in discriminating pathological changes due to the abnormal lung function in a mechanically ventilated patient.


Asunto(s)
Pulmón/diagnóstico por imagen , Respiración con Presión Positiva , Síndrome de Dificultad Respiratoria/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Humanos , Pulmón/fisiopatología , Masculino , Persona de Mediana Edad , Síndrome de Dificultad Respiratoria/fisiopatología , Síndrome de Dificultad Respiratoria/terapia , Ventiladores Mecánicos , Capacidad Vital
19.
Coll Antropol ; 23(2): 495-509, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10646224

RESUMEN

Since the discovery of the Tyrolean Iceman in 1991, advanced imaging and post-processing techniques have been successfully applied to anthropological research. Among the specific techniques are spiral computed tomography and 3-dimensional reconstructions, which include stereolithographic and fused deposition modeling of volume data sets. The Iceman's skull was the first to be produced using stereolithography; subsequently, it has been successfully applied in preoperative planning. With the advent of high-end performance graphics workstations and biomedical image processing software packages, 3-dimensional reconstructions have become established as routine tools for analyzing volume data sets. These techniques enabled dramatically new insights to be gained in the field of physical anthropology. Computed tomography became the ideal research tool to access the internal structures of various precious fossils without even touching--let alone damaging--them. Among the most precious are specimens from the genus Australopithecus (1.8 Myr-3.5 Myr), as well as representatives of Homo heidelbergensis (200 kyr-600 kyr) and Homo neanderthalensis (40 kyr-100 kyr); such fossils have been CT-scanned during the last five years. The fossils often are filled with a stone matrix or other encrustations. During the post-processing routines, highly advanced algorithms were used to remove these encrustations virtually (the concrete fossils remain untouched). Thus it has been possible to visualize the morphological structures that are hidden by the matrix layer. Some specimens have been partially destroyed, but it has been possible for the missing parts were reconstructed on the computer screen in order to get estimations of brain volume and endocranial morphology, both major fields of interest in physical anthropology. Moreover, the data in computerized form allows new descriptions of morphological structures using geometric morphometrics. Some of the results may change aspects and interpretations in human evolution and approaches to long-standing questions in this field. We subsume the introduction of these new imaging and post-processing techniques into a new field of research: Virtual Anthropology.


Asunto(s)
Momias/diagnóstico por imagen , Animales , Simulación por Computador , Historia Antigua , Hominidae , Humanos , Procesamiento de Imagen Asistido por Computador , Modelos Anatómicos , Paleopatología/métodos , Tomografía Computarizada por Rayos X
20.
Coll Antropol ; 23(2): 397-405, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10646215

RESUMEN

The endocranial capacity of Guattari 1 originally was estimated by Sergi as approximately 1.550 cm3. Using three different approaches, a physical endocast, a stereolithographic model, and a virtual endocast, we have estimated the endocranial capacity of Guattari 1 as approximately 1.350 cm3. This paper explains our revision of the estimated endocranial volume of Guattari 1, provides a cautionary case concerning other estimates of endocranial volume, and demonstrates and encourages the use of recent advances in imaging, modeling, and analysis of endocranial volume.


Asunto(s)
Hominidae/anatomía & histología , Animales , Historia Antigua , Humanos , Paleontología , Cráneo/anatomía & histología
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