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Left ventricular ejection fraction was measured by magnetic resonance imaging (MRI) and compared with standard monoplane left ventriculography in 46 patients with various cardiac diseases. Two different MRI strategies were used. In 28 patients (group 1), ejection fraction was determined using a single slice comparable with the right anterior oblique projection of the ventriculogram. Comparison of left ventricular ejection fraction yielded a poor correlation between single slice MRI (y) and ventriculography (x) (y = 28.7 + 0.47 x, r = 0.65). In 18 patients (group 2), a multiple contiguous slice MRI technique was used to allow ejection fraction and stroke volume determination by summing up the volumes of ventricular cavity intersections. Regression analysis showed a high correlation between multiple slice MRI (y) and ventriculography (x) (y = 7.2 + 0.88 x, r = 0.98). Also, correlation between MRI right (y) and left (x) ventricular stroke volumes was satisfactory, (y = -12.8 + 1.09 x, r = 0.83). It is concluded that the multiple slice imaging technique in MRI provides an accurate noninvasive means for quantification of left ventricular ejection fraction that can be extended to the determination of left ventricular volume.

Seventy-eight patients were investigated by magnetic resonance (MR) imaging using optimal scan parameters and a surface coil. Forty-two patients were also examined by computer tomography (CT). Sixteen patients underwent laryngectomy. MR imaging of cancerous tissue in the larynx, and particularly of non-invaded and invaded cartilages, was examined by comparing MR images with sliced surgical specimens. Pre-operative CT and MRI findings were evaluated by comparing them with postoperative histopathological findings. MR T1-weighted images demonstrate localisation and extent of cancerous tissue. With combined use of T1-weighted and proton-density images MR imaging is superior to CT for showing cartilage invasion. Unfortunately, gross movement artifacts, which resulted in non-diagnostic images, occurred in 16% of the examinations.

Magnetic resonance imaging of the heart, and more specifically of the left ventricle (LV), is optimized by using oblique imaging planes adapted to the long and short axes of the LV, comparable to other imaging modalities in cardiology. We report a procedure to perform two chamber views, four chamber views and true short axis views by combinations of electronic axial rotations. The technique of selecting appropriate gradient angles is explained. Thus, there is no requirement for altering patient position in the imager, while individual anatomic variations are taken into account.

A standard procedure was developed allowing study of cardiac anatomy with electrocardiographically gated MRI, using alteration of a single gradient angle of the imaging plane combined with patient rotation. This resulted in projections of the heart through its anatomical axes. The obtained images allow correlation with 2D-echocardiography and left ventriculography.

A combined angiographic-cisternographic approach is described by which small tumours originating from the medial wall of the temporal lobe can be detected, even when conventional neuroradiological techniques failed to do so. The cisternographic technique used in these cases is described in detail and other applications of this procedure are demonstrated.

A case of Sotos' syndrome (cerebral gigantism) is described. Pneumencephalography, performed at the age of 15 days, revealed abnormal separation of the opercula on the right. By comparing the contours with developmental anatomical features of this area it agreed with a foetal development of 24 weeks gestational age. Bilateral carotid angiography was normal. CT showed normal development of the Sylvian area at the age of 27 months.

Anomalies of the corpus callosum (CC) in children can be subdivided into two main categories: Malformations (also known as dysgenesis) and damage to a previously well-formed callosum. Pre- or perinatally acquired damage may have a mainly vascular, obstructive or hypoxic-ischemic etiology, whereas endotoxins and exotoxins might also play a role. Early postnatally acquired CC damage in children is mostly of vascular or traumatic origin. In some instances the CC is thinned after chronic pressure (e.g. in hydrocephalics). Nineteen of fifty children with psychomotor retardation had CC anomalies, most of them suggestive of acquired damage. Mild forms of CC anomalies are visible with MRI, but might be missed with a CT-scan. Children with acquired CC anomalies have signs of supposed Interhemispheric Disconnection (ID), which is partly responsible for their clinical syndrome of mental and motor retardation. The likelihood of finding a CC anomaly in a child seems to be enhanced by the predictive use of neuropsychological tasks indicative for ID.

Ultrasound examinations (US) of the brain are possible in the presence of an acoustic window in the skull, either after craniotomy or through an open fontanelle. In this study 19 children were examined, 11 via a suboccipital craniectomy; 9 cases were examined more than once. Via this suboccipital route most of the contents of the posterior fossa, the third and lateral ventricles could be made visible. In two patients with a temporal or parietal craniotomy the involved hemisphere could be visualized. Six patients were examined via the open fontanelle after insertion of a ventriculoperitoneal shunt (VPS). In three of these cases the examination was undertaken to evaluate also a posterior fossa cyst. The findings were compared with CT if the findings were equivocal.

A case of an anterolateral lumbar meningocele in a patient with neurofibromatosis is presented. As anterolateral lumbar meningocele may present itself only by non-specific symptoms like low back pain or abdominal pain, such symptoms require prompt diagnostic work up in patients with neurofibromatosis. The significance of MR imaging in early recognition of this rare anomaly is emphasized.

Forty-four consecutive patients with laryngeal carcinomas presenting at different stages of the disease were investigated by magnetic resonance (MR) imaging. Twelve patients (six with primary lesions and six with recurrent tumors) underwent laryngectomy, and the macro- and microscopic appearance of the slice specimens were correlated with MR imaging. In the remaining patients surgery was not performed, and MR results are compared with the laryngoscopic findings. Cancerous tissue was seen on T1-weighted images as a homogeneous mass of intermediate signal intensity. slightly higher than infrahyoid muscles. The MR examinations failed mainly in patients with tumor recurrence who had undergone previous radiation treatment.

For the demonstration of brain metastases both CT and MRI are available as diagnostic modalities. To compare both imaging methods as to their sensitivity in detecting brain metastases CT scans and MR images of 60 patients with suspected brain metastases were evaluated. Comparing contrast-enhanced CT and plain MRI neither modality was found to be clearly superior in this respect.

A case of the Joubert Syndrome is reported. This syndrome, of which 11 cases have hitherto been described, is characterized by aplasia of the cerebellar vermis in addition to episodic hyperpnoea, abnormal eye movements, rhythmic protrusion of the tongue, ataxia, and mental retardation. The diagnosis was made by the clinical symptoms, computerized axial tomography of the brain, and lumbar pneumencephalography. Bilateral typical colobomata of retina and choroid were an additional anomaly, described for the first time in association with the Joubert Syndrome. The possible relationship between the ocular and cerebral anomalies is discussed.

Embolization to treat intractable epistaxis is becoming increasingly popular. Twelve cases of facial nerve paralysis after embolization of branches of the external carotid artery have been reported. In this paper, a new case is reported. In epistaxis, embolization should be reserved for patients with contraindications to ligation or in emergency procedures.

Five patients with sickle cell disease have been studied by magnetic resonance imaging (MRI) in three instances during a crisis. Attention was directed to the pelvis and lower extremities. Bone marrow pathology has been classified according to generalised or circumscribed alterations in signal intensity on T1 weighted spin-echo sequences. Both acute and chronic changes were observed.

CT-scan findings of the brain in two children with true histiocytic sarcoma are described as well as their changes during therapy. Clinical features and differential diagnosis on CT-scan examination are discussed. Follow-up CT-scan during therapy is of value as an indicator of the response to therapy and possibly the long term prognosis.

This report concerns a clinical trial with gadolinium-DTPA (Gd-DTPA) as an intravenous contrast medium for magnetic resonance imaging (MRI) in patients with disorders of the central nervous system. Fifty patients, 30 females and 20 males, were examined without and with Gd-DTPA. The contrast medium was well tolerated by all patients. The results of MRI scanning without and with Gd-DTPA and those obtained with computed tomography (CT) using intravenous contrast enhancement were compared. This investigation comprised mainly patients with intracranial tumors, multiple sclerosis, and nasopharyngeal tumors. The results may be summarized as follows: 1) MRI with Gd-DTPA (MRI+) gave better results than MRI without Gd as regards delineation of the lesion, blood vessels and edema in cerebral tumors, pituitary adenomas and acute forms of multiple sclerosis (MS). 2) MRI+ was better than CT in 32 of the 50 cases examined; with intracerebral tumors it was better in 15 out of 18 cases. 3) MRI+ was always better than CT in patients with MS. In 3 out of 7 cases MRI demonstrated the acute MS lesions. 4) MRI+ seemed to have advantages also in nasopharyngeal tumors as ascertained from this limited experience.

A case of congenital multiple angiomatosis with cerebral involvement is presented. Postmortem investigation showed identical angiomas on skin and brain. The cerebral vascular tumor has caused altered vascularization of the hemisphere, resulting in a development arrest of the corpus callosum and a fetal appearance of the parietal and temporal vessels.

In 28 patients with various cardiac diseases we compared ejection fractions obtained by magnetic resonance imaging in a single oblique slice with monoplane ventriculography in the right anterior oblique projection, the latter serving as the standard. Also, results were evaluated for clinical relevance and relation to image quality. The correlation between the two techniques was moderate (r = 0.65). According to our standardized limits for clinical relevance, insufficiently correlating ejection fractions were obtained in 14 patients. In 8 of these patients this was attributed to poor endocardial edge detection. Edge detection problems were more frequently encountered by imaging with echo-time 20 msec than with echo-time 32 msec. Other causes for mismatching of the obtained ejection fractions are discussed. It is concluded that determination of ejection fraction by single slice magnetic resonance imaging should not be used for clinical application. Improvement can be expected by using a contiguous slicing technique, a longer echo-time in the spin-echo pulse sequence, or in due course by application of newly developed fast-imaging pulse sequences.

A 3 1/2-year-old boy with this syndrome is reported. The clinical features were: linear organoid nevus, characteristically involving the midline of the face with extension to one side (right side in this case), hemimacrocephaly, mental and motor retardation, epilepsy originating from a focus in the right hemisphere, a malformed hemisphere and ventricular system on the right side on pneumoencephalographic and angiographic study and a hamartoma-like malformation protruding into the frontal horn of the right lateral ventricle.

MRI appearances of laryngeal cartilages, normal or invaded by cancer, are still relatively unfamiliar to most clinicians. Twelve primary laryngeal tumors out of a series of 65 patients which have been investigated by MRI were examined postoperatively by macroscopic and microscopic sectioning of the surgical specimens. Images were obtained with a 0.6 Tesla superconductive system using a solenoid surface coil. The authors emphasize the value of a combined use of T1-weighted and balanced (relatively T2-weighted images with still T1-characteristics) Spin Echo images. T1-weighted images permit differentiation between pathological and normal bone marrow. Balanced images allow separation between nonossified cartilage and tumor tissue. MRI is an additional tool in the diagnostic workup of cartilage invasion by tumor.

The authors report on their early results in the ultrasound (US) follow-up of postoperative brain pathology, both supra- and infratentorial. The use of US is dependent on the presence of an acoustic window in the skull after craniotomy. Five patients were investigated via a suboccipital craniotomy and one patient via a temporal skull defect. In the patients with a suboccipital craniotomy the greatest part of the posterior fossa, the 3rd and lateral ventricle could be made visible. In a patient with a temporal craniotomy the involved parts of the brain were demonstrated satisfactorily. If a skull defect persists after surgery US may be of value in the follow-up of postoperative conditions, such as the assessment of tumour residue or recurrence, hydrocephalus, postoperative complications and response to radio- or chemotherapy.

Among 100 patients with an infarction of the brain reported on MR and clinically confirmed there were 4 with widespread lesions of the temporal and occipital lobes, thalamus, midbrain, pons and cerebellum, all supplied by arteries originating around the top of the basilar artery. Clinically these patients presented the "top of the basilar" syndrome, which is caused by a disturbance in circulation at the top of the basilar artery. Which brain areas are involved may be deduced theoretically from the vascular anatomy. These lesions can, we believe, be clearly detected using MR, because of its sensitivity to ischaemic disturbances and in the posterior fossa. We report our 4 patients here to illustrate the clinical presentation and MR findings of the "top of the basilar" syndrome.

Eighteen patients underwent computed tomography (CT) prior to total laryngectomy. In order to assess the accuracy of CT scanning in the evaluation of carcinoma of the larynx, CT scans were prospectively interpreted and the extent of the tumour was recorded. The tumour extent was evaluated on whole-mount histologic sections of the laryngeal specimens, prepared in the horizontal plane, similar to the CT scan. The results were compared to assess the ability of CT to identify tumour infiltration in the horizontal plane accurately. Based on these findings it is clear that CT has its influence on the T-staging and on the choice of treatment of laryngeal cancer, i.e. radiotherapy versus surgery.

Unilateral magnetic resonance imaging (MRI) of the symptomatic temporomandibular joint (TMJ) was performed on 55 patients. The position of the articular disc in relation to the condyle was established on sagittal images. Particular attention was paid to partial or complete anterior positioning of the disc. MRI was correlated with clinical and, in 33 cases, surgical findings. The concept of partial anterior displacement may be useful in relation to treatment planning.

Twenty-two cases of intramedullary spinal tumours with cystic parts and 22 cases of hydrodynamic syringomyelia were classified according to criteria such as age at onset, duration of symptoms, nature of neurologic symptoms and a number of imaging parameters. The criteria used proved to be helpful in making the correct diagnosis.