Search PubMedSearch

SEARCH · Search PubMed

Results for “CT-scan”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

16 recordsLinked to original sources

Diagnosis and localization of pheochromocytoma. Detection by measurement of urinary norepinephrine excretion during sleep, plasma norepinephrine concentration and computerized axial tomography (CT-scan).

The feasibility of differentiating patients with pheochromocytoma from other hypertensive patients by measuring urinary excretion rates of norepinephrine during sleep, a period of physiologic suppression of norepinephrine release, was investigated. The mean excretion rates of norepinephrine in 248 normal subjects and in 109 patients with essential hypertension were 1.03 +/- 0.03 and 1.12 +/- 0.06 (SEM) micrograms/hour, respectively, whereas the lowest excretion rate among the six patients with pheochromocytoma was about seven times higher. Plasma norepinephrine concentration in patients with pheochromocytoma was also consistently above the range observed in both normotensive and hypertensive subjects. CT scan correctly identified the same tumors visualized by selective arteriography. It is suggested that the usefulness of these approaches will provide simpler means of screening and detecting pheochromocytoma.

Adolescent

Small ventricles detected by CT-scanning in epileptic patients.

Relatively young 119 cases of generalized epilepsy and 99 controls of an identical age were selected. The bicaudate CVI was measured and the results were as follows: 1) In our cases, the mean of bicaudate CVI showed a smaller value than those of Hahn's in both epilepsy and control groups. 2) When the value of bicaudate CVI was set up below the point of 8.5 as "excessively small ventricle," the incidence rate of "excessively small ventricle" was 9% in the control group and 31% in the epilepsy group. The data showed higher incidences of small ventricles in the epilepsy group, and that the younger females have a tendency to have higher incidences of small ventricles. 3) To make clear the reason for the higher incidences of small ventricles in epilepsy, the small ventricle group and the non-small ventricle group in epilepsy were compared with each other from the points of the clinical course, EEG findings and frequency of attacks. No correlation or difference between them was found. Further investigation will be needed to make clear the etiology of small ventricles in epilepsy. However, it could be said at the present stage that not so many atrophic changes were observed in the younger patients of generalized epilepsy.

Adolescent

[An information retrieval system for CT-scan data (author's transl)].

A computer program for the current statistical documentation and evaluation of CT diagnostic results is presented. A diagnostic key for the purposes of CT results has been developed. Special emphasis has been given to fast and simple applicability.

Central Nervous System Diseases

The accuracy of tc-scan in the diagnosis of retroperitoneal metastases of malignant testicular tumours.

Based on the investigations carried out on 18 patients with testicular tumours, the results of CT-scanning are compared with the findings of conventional radiological examination and with lymphography in particular. At the actual state of technical evolution, the study reveals that CT-scanning does not possess sufficient spatial resolution to permit the diagnosis of very small lymph node metastases and all the more of a specific diagnosis of these metastases. Nevertheless, it remains a fact that CT-scanning obviously is a preferable method with respect to the visualisation of the exact extent and size of large involvements and the effects upon the surrounding tissues. CT-scanning is proposed as the screening-procedure with regard to patients suffering from testiscarcinoma, and allows, in a great number of cases, to make more invasive techniques superfluous.

Humans

Intellectual development and brain size in 13 shunted hydrocephalic children.

A group of 13 successfully treated hydrocephalic children living a normal social life according to their ages has been examined to evaluate the possible correlation between their brain size, intellectual development and physical disability. The brain size was assesed by ventriculography prior to initial surgery and by computer tomography (CT-scanning) at the time of investigation 6--11 years after operation. The intellectural development was evaluated by psychological investigation of the children and by evaluation of their social adaptation. The physical disability was investigated by neurological examination. Significant improvement in ventricular size was demonstrated from pneumoencephalographic examinations prior to surgery and to the CT investigations. No prediction of the intellectual development could be based on the ventriculographies prior to initial surgery. In spite of positive trends, correlation trends, correlation between the ventricular size as determined by CT-scans and the IQ was not significant, possibly due to the small number of cases available for study.

Cerebral Ventriculography

[Ossification of the posterior longitudinal spinal ligament--comparative studies with computerized tomography (author's transl)].

Ossification of the posterior longitudinal spinal ligament (OPLL) was characterized by calcified longitudinal band along the posterior margin of vertebrae, but it has not been possible to know how the cord is compressed within the narrowed spinal canal. Our neuroradiological studies based on CT-view of the 15 cases of OPLL suffering from various degree of myelopathy revealed: 1) Computed tomography precisely delineated shape of OPLL, which was quite polymorphic, like mushroom, irregular cubic and round. OPLL ranged more than two vertebrae was not uniform, but exhibited different configuration at each level. 2) OPLL at lower cervical and higher thoracic regions was difficult to diagnose by conventional lateral roentgenograms, but CT-scan demonstrated clearly whole extent of OPLL. 3) obliteration ratio of the affected spinal canal was calculated on CT-scan. Cases showing severe myelopathy, such as quadriparesis and neurogenic bladder, presented spinal canal stenosis of more than 30%. Spondylosis were concomittant roentgenographic findings on 13 cases of OPLL (87%). However, spondylotic changes responsible to the myelopathy were seen on only three cases. In these case, the obliteration ratio by ossificated ligament was lower than 26%. On conclusion, computed tomographic views of OPLL gave us more detailed information about the stenotic spinal canal and found to be essential examination when considering operative intervention.

Aged

Adaptive or non-adaptive? Cranial evolution in a radiation of miniaturized day geckos.

Lygodactylus geckos represent a well-documented radiation of miniaturized lizards with diverse life-history traits that are widely distributed in Africa, Madagascar, and South America. The group has diversified into numerous species with high levels of morphological similarity. The evolutionary processes underlying such diversification remain enigmatic, because species live in different ecological biomes, ecoregions and microhabitats, while suggesting strikingly high levels of homoplasy. To underscore this evolutionary pattern, here we explore the shape variation of skull elements (i.e., cranium, jaw and inner ear) using 3D geometric morphometrics and phylogenetic comparative methods on computed tomography scans (CT-scan) of a sample encompassing almost all recognized taxa within Lygodactylus. The results of this work show that skull and inner ear shape variation is low (i.e., there is high overlapping on the morphospace) across geographic regions, macrohabitats and lifestyles, implying extensive homoplasy. Furthermore, we also found a strong influence of allometry shaping cranial variation both at intra and interspecific levels, suggesting a major constraint underlying skull architecture, probably as a consequence of its miniaturization. The remaining variation that is not allometric is independent of phylogeny and ecological adaptation and can probably be interpreted as the result of intrinsic developmental plasticity. This, in turn, supports the interpretation that speciation in this group is largely concordant with a non-adaptive hypothesis, which results mainly from vicariant processes.

Animals

Hydrocephalus-dementia-complex in Paget's disease.

The clinical triad of gait disturbances, memory impairment and urinary incontinence is associated with a communicating hydrocephalus in the 'normal pressure hydrocephalus'-syndrome. The authors present a case of H.D.C. (hydrocephalus-dementia-complex) in Paget's disease with an identical syndrome, but with obstructive hydrocephalus, causing a triventricular dilatation. Today, each case of mental deterioration in Paget's disease, should be immediately observed and neurosurgical intervention kept in view. An X-ray of the skull, a CT-scan of the brain and a cisternography are performed as routine procedure. If there are indications of involvement of the basis of the skull, hydrocephalus and/or disturbed pattern of the tracer-migration around the convexities, associated with a certain degree of dementia, impaired gait or urinary incontinence, a ventriculo-subcutaneous drain should be inserted. If clinical improvement follows, a ventriculatrial shunt is indicated. The post-operative clinical outcome seems to be dependent on some clinical and technical factors. The most eventful outcome is observed in cases where the clinial triad, described in patients with a classical 'normal pressure hydrocephalus'-syndrome, is associated with an obstructive hydrocephalus, due to a stenosis of the Sylvian aqueduct.

Cerebrospinal Fluid Shunts

Reflux of metrizamide into the lateral ventricles in vomiting.

Two cases are presented in which metrizamide refluxed into the lateral ventricles after vomiting, the contrast having been brought in intrathecally by lumbar route for CT-scanning of the basal cisterns. It is suggested the intrathoracic and intraabdominal pressures transority achieved in vomiting are transmitted to the spinal canal through the vertebral venous plexus. This results in a pressure which is transmitted through the C.S.F. to the posterior fossa, and from there, for anatomical reasons, to the ventricular system. Transitory dilatation of the ventricles results in aspiration fluid from the fourth ventricle, and hence reversal of normal flow in the aqueduct of Sylvius.

Cerebral Ventricles

Computerized axial tomography: clinicopathologic correlation.

Between August 1973 and April 1974 more than 750 patients had computerized axial tomography (CT) scans at the Massachusetts General Hospital. Ten brains from previously CT-scanned patients in this group were sectioned in the plane of the scan. Nearly exact correlation was found between the anatomic location and extent of intracranial lesions demonstrated by CT scan and the findings on gross and microscopic pathologic examination in cases of primary intracranial tumors, obstructive hydrocephalus, intracerebral hemorrhage, ischemic and hemorrhagic infarctions, pineal tumor, and thermal-burn encephalopathy. Determination of absorption values (mu) of 47 pathologically verified processes showed that high-absorption intracerebral hemorrhage and calcium-containing tumors are readily separable from other processes on the basis of mu values alone. However, the abnormal mu values of primary brain tumor, edema, and infarction are difficult to distinguish from those of normal spinal fluid and white matter.

Autopsy

Localization of hormone-producing gastrointestinal tumours by ultrasonic scanning.

The value of ultrasonic scanning in the localization of hormone producing gastrointestinal tumours was assessed in 16 patients. Fifteen patients had Zollinger-Ellison syndrome and one patient had a VIP tumour. In four patients with Zollinger-Ellison syndrome ultrasonic scanning demonstrated a solid mass lesion of the head of the pancreas of 2.2.4 and 8 cm respectively. One of these diagnoses was verified by autopsy, one was also found by subsequent CT-scanning and angiography. In one patient ultrasonic scanning demonstrated a 3 cm tumour of the tail of the pancreas. At ultrasonically guided percutaneous fine needle biopsy tumour cells were aspirated. Biochemistry confirmed a VIP tumour. In 11 patients ultrasonic scanning was normal. By laparotomy in nine of these tumours of 1--3 cm were found in three patients 5.9 and 15 months after scanning and in two patients multiple 0.5 cm tumours within the duodenal wall were demonstrated one half and 9 months after ultrasound. In four patients tumours were not demonstrated by surgery. Two of the 11 patients were not operated upon, and the tumours have not been localized. The advantages of the complete atraumatic, rapid and relatively cheap ultrasound technique and the ability of an ultrasonically guided biopsy for the demonstration of malignancy justify ultrasonic scanning to be an initial method of investigation in the localization of hormone producing gastrointestinal tumours.

Evaluation Studies as Topic

The relationship between intellectual skills and the computerised axial tomograms of children with spina bifida and hydrocephalus.

Cranial CT-scans of 467 patients were graded in degrees of severity of hydrocephalus. The patients were aged from 2-22 years and had spina bifida and/or hydrocephalus or related disorders. Even large increases in the degree of hydrocephalus were found to have an insignificant effect upon verbal IQ, but there was a small but statistically significant effect upon performance scale IQ on the WISC. The abilities most affected were those involving the use of motor and perceptuo-motor skills. Assymetrical or other abnormal scans were found to be associated with lower IQ. Children with valves were only found to be substantially inferior in skills to those without valves when their ventricles were either very large, or abnormally small. The highest proportion of children with valves was found in the group with the smallest ventricles. Very small ventricles are known to be associated with an increased rate of valve complications, and this paper shows that there are psychological disadvantages also.

Adolescent

[Ct-criteria of orbital hemangiomas and their importance in differential diagnosis of intraconal tumors (author's transl)].

CT-scans of 29 histologically proven cavernous hemangiomas were evaluated with respect to their location, shape, delineation from surrounding tissue, contrast-enhancement, and secondary changes of the bony orbit. Whenever a round or oval tumor, located in the outer upper muscle cone, sharply delineated from surrounding tissue, unattached to optic nerve and ocular muscles, spares a small triangular space in the orbital apex, it is in all probability a cavernous hemangioma. Evaluation of the tumors shape and its separation from surrounding tissues requires imaging in multiple sections in two planes oriented, if possible, at right angles. -- Changes in position of the optic nerve and eye muscles in different directions of gaze demonstrated by CT rule out significant tumor-attachments. The portion of the intraconal space least affected by optic nerve shifts and muscle contractions during eye movements, as demonstrated by CT, is the upper outer quadrant, the site preferred by the mobile tumor. -- Tumors which cannot be differentiated from cavernous hemangiomas by CT-criteria are rare usually benign. Reports of rare examples of well delineated or encapsulated malignant intraconal lesions indicate the possibility -- however remote -- of mistaking a malignant tumor for a cavernous hemangioma by CT.

Diagnosis, Differential

[A case of nasofrontal encephalomeningocele with review of literatures and experiences of 14 cases of cephaloceles (author's transl)].

A case of 2-month-old boy with nasofrontal encephalomeningocele was presented, which was excellently treated via intradural approach, followed by removal of herniated sac. Under the knowledge of reviewed literatures and our experiences of 14 cases of cephaloceles, its symptomatology, diagnosis and policy of treatments were discussed. As rare case was an intracranial meningoencephalocele in our series described, which showed a supracollicular cyst with brain tissue wall, communicating with aqueduct. Other emphases were placed on the differential diagnosis from holoprosencephaly with extracranial dorsal sac, the usefulness of CT-scan as a diagnostic tool and our method of closing dural defects in anterior cranial fossa by reflecting dura on frontal lobe.

Encephalocele