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H Henkes

Publications and source records attributed to H Henkes.

At least 19 recordsLinked to original sources
PubMed1992

[Border-area cerebral ischemia--3D-SPECT for the imaging of the regional cerebral blood flow].

15 patients with suspected cerebral ischaemia were examined using 99mTc-HM-PAO-SPECT to assess cerebral blood flow. Results obtained from SPECT were correlated with CT and Doppler ultrasound findings. A 3D-display algorithm is proposed to enhance the lesion to non-lesion contrast compared to the standard 2D-image interpretation. In all cases contrast was superior on 3D-display to 2D-display (-0.38 versus -0.09). 3D-display of SPECT-data enhances lesion contrast due to postreconstructive data processing and may improve exact interpretation of cerebral blood flow studies.

Adult↗
PubMed1992

[The determination of cerebral dopamine (D2) receptor density by using 123I-IBZM-SPECT in Parkinson disease patients].

An alteration of the dopaminergic nigrostriatal system is believed to be the main pathogenetic factor of Parkinson's disease (PD). We report on our initial results on the determination of the post-synaptic dopamine-D2-receptor binding of 123I-IBZM in patients with PD. Drug-native patients showed a significantly higher IBZM binding in the basal ganglia as compared to patients on specific dopaminergic medication. Age, duration of the disease and the severity of the disease do not seem to influence the IBZM-receptor binding. We conclude that 123I-IBZM-SPECT is an extremely useful tool for the evaluation of the functional state of cerebral dopamine-D2-receptors.

Aged↗
PubMed1992

[Tuberous sclerosis: broadening of the diagnosis using MR tomography and computed tomography].

Ten children and a 22-y old women with tuberous sclerosis were studied. All children were epileptic but only 8 had skin lesions (white spots, sebaceous adenoma), 4 had rhabdomyoma of the heart and 4 children had astrocytoma of the retina; only in 4 children was the entire triad of tuberous sclerosis seen. The young woman with a hemorrhage of an angiolipoma of the kidney had no other symptoms of tuberous sclerosis. All patients had pathologic CT and MRT findings; 4 different types of lesion were seen in MRT. In order to elucidate human genetic aspects and to demonstrate the underlying disease all children with epileptic disorders and also all patients without the full triad of symptoms should be examined by MRT.

Adult↗
PubMed1991

Increased rCBF in gray matter heterotopias detected by SPECT using 99mTc hexamethyl-propylenamine oxime.

Imaging findings of morphology and regional cerebral blood flow in two patients suffering from epileptic seizures are presented. CT and MRI revealed heterotopic gray matter as a probable structural correlate, causing the seizure disorder. 99mTc hexamethyl-propylenamine oxime (HM-PAO) SPECT demonstrated focally increased regional cerebral blood flow in both patients in the areas of their heterotopic lesions. Heterotopic and orthotopic gray matter seem to have similar features in terms of regional perfusion. A focally increased brain perfusion in interictal epileptic patients may indicate an underlying migration anomaly.

Adult↗
PubMed1991

[The demonstration of calcifications in magnetic resonance tomography (MRT). The effect of different parameters on the MRT imaging of cerebral calcifications].

The effect of various factors on the demonstration of calcified lesions was studied in 131 areas of calcification which had been demonstrated by CT. By means of MRI (SE 400/30 or GE315/14, 90 degrees and SE 1600/30 + 70; 0.5T) 117 of the 131 calcified lesions (89%) produced a signal difference. Of these 117 lesions, 80 (61%) were recognised as calcification by MRI. Large areas of calcification (more than 5 mm) and high density calcification (more than 100 Hu) were recognised significantly more often than small or low density calcifications. T2-weighted images demonstrated calcification more often than other sequences. With conventional pulse sequences, calcified lesions were frequently recognised as abnormalities on MRI, but their recognition as calcified lesions is unreliable.

Brain↗
PubMed1991

[Magnetic resonance tomographic screening studies of the bone marrow with gradient echo sequences: (I) the contrast relations of phase-identical and phase-shifted gradient echo sequences. Studies on probands and pathological-anatomical preparations].

Anatomical specimens and normal persons were studied by gradient echo MR imaging to determine the influence of different echo times (TE) on bone marrow contrast. First of all, six normal persons were studied to determine specific echo times for in-phase and opposed-phase states. Using different sequences bone marrow contrast in isolated femoral bones was determined and compared to results of pathological exams. Red bone marrow had no signal on opposed-phase images; contrast between red and yellow marrow was higher on opposed-phase than on in-phase images. Bone marrow lesions can be expected to be visualised with high signal on opposed-phase images; this technique should be especially suited for MR imaging of bone marrow.

Adult↗
PubMed1991

[Cerebral MRT in x chromosome linked adrenoleukodystrophy].

Adrenoleukodystrophy (ALD) is a rare lipid storage disease, characterized among other symptoms by a progressive demyelinization of white matter. Changes are well demonstrated by MRT: Leukencephalopathy begins symmetrically in the occipital lobes of the cerebrum and involves furthermore the splenium of the corpus callosum, the nucleus dentatus and the descending tracts. As neurologic signs may precede signs of adrenal insufficiency, MRT may be important to suspect the diagnosis of ALD, which generally is diagnosed by biochemical tests.

Adrenoleukodystrophy↗
PubMed1991

[MRT and 99mTc-HM-PAO SPECT of the brain in myasthenia gravis].

Fourteen patients suffering from myasthenia gravis underwent cranial MRI and 99mTc-HM-PAO SPECT examinations. T2-WI revealed solitary white matter and/or basal ganglia lesions in four, multiple lesions in eight patients. The evaluation of the rCBF demonstrated a circumscript decrease of cortical perfusion in one patient whereas eight patients showed multiple cortical areas of hypoperfusion. In the context of an increased incidence of intrathecal immune reaction as well as of a constantly impaired cognitive performance of these patients, imaging findings might be a correlate of a primary cerebral manifestation of myasthenia.

Adult↗
PubMed1991

[Venous anomalies of the brain. The clinical significance of the so-called venous angioma].

In contrast to angiography, MRI not only allows the diagnosis of DVA (developmental venous anomaly, so-called venous angioma), but also shows up cavernomas and other angiographically occult vascular malformations. It also differentiates between DVAs and occult true malformations. This has completely changed the pathological assessment of DVAs. In a retrospective study on 31 patients with angiographically proven DVAs neighbouring cavernoma was a frequent finding (15 patients, 48% group I). Symptoms caused by cavernoma were present in 6 (40%) of these 15 patients. The following associations were also found: cerebral arterial aneurysm (2), spinal arterio-venous dural fistula (1), dermal haemangioma (1), Klippel-Trénauny syndrome (1). Only 16 (52%) of the 31 cases with DVA were free of associated cavernoma (group II). Only 3 (19%) of these patients with a solitary DVA were symptomatic. In our series we have seen no case of bleeding from a DVA. A DVA is a vascular anomaly characterized, like other anomalies, by reduced resistance and limited capacity for regulation and adaptation. In rare cases this can result in haemodynamic disturbances, thrombosis and ischaemia. Wall rupture with bleeding does not occur in DVA. It must be assumed that bleeding reported in patients with DVAs before the availability of MRI resulted from an associated true vascular malformation in most cases.

Adolescent↗
PubMed1991

[Sturge-Weber syndrome. Diagnostic imaging relative to neuropathology].

Clinical presentation of a child with port-wine stain and seizures leads to the suspicion of Sturge-Weber disease (SWD). This diagnosis can be confirmed by the detection of a meningeal angiomatosis. In rare cases, early detection of meningeal pathology by ultrasound has been reported. Key findings are brain atrophy, gyriform cortical calcifications demonstrated by skull radiographs after the first year of life or earlier by cranial CT, and dys- or aplasia of the deep cerebral veins on angiography. Radionuclide imaging shows focal or diffuse tracer accumulation over the affected brain regions. MR demonstrates an abnormal appearance of the affected meninges, especially thickening and pathologically increased signal intensity after Gd-DTPA application. This, in association with the demonstration of abnormal enhancement in deep medullary veins, is the most characteristic finding. Contrast-enhanced MR allows early and non-invasive diagnosis of SWD, mainly by revealing leptomeningeal angiomatosis and abnormal venous vessels.

Adolescent↗
PubMed1991

[Radionuclide cisternography: SPECT- and 3D-technique].

Radionuclide cisternography is indicated in the clinical work-up for hydrocephalus, when searching for CSF leaks, and when testing whether or not intracranial cystic lesions are communicating with the adjacent subarachnoid space. This paper demonstrates the feasibility and diagnostic value of SPECT and subsequent 3D surface rendering in addition to conventional rectilinear CSF imaging in eight patients. Planar images allowed the evaluation of CSF circulation and the detection of CSF fistula. They were advantageous in examinations 48 h after application of 111In-DTPA. SPECT scans, generated 4-24 h after tracer application, were superior in the delineation of basal cisterns, especially in early scans; this was helpful in patients with pooling due to CSF fistula and in cystic lesions near the skull base. A major drawback was the limited image quality of delayed scans, when the SPECT data were degraded by a low count rate. 3D surface rendering was easily feasible from SPECT data and yielded high quality images. The presentation of the spatial distribution of nuclide-contaminated CSF proved especially helpful in the area of the basal cisterns.

Adult↗
PubMed1990

"Meningeal sign": a characteristic finding of meningiomas on contrast-enhanced MR images.

In meningiomas, a flat, contrast-enhancing, probably dural structure adjacent to the tumor can occasionally be observed on Gadolinium-DTPA enhanced MR images. This so called "meningeal sign" was evaluated with respect to the differential diagnosis of meningiomas in MR imaging. The study included 29 patients with intracranial meningiomas and 24 patients with non-meningeal brain tumors. In all meningiomas, MR studies included T2-weighted as well as unenhanced and Gadolinium-DTPA-enhanced T1-weighted images. In all non-meningeal tumors, Gd-DTPA-enhanced MR images were available. All images were evaluated with respect to the presence of the "meningeal sign". In meningiomas, a "meningeal sign" was seen in 15/29 cases on Gadolinium-DTPA-enhanced images. No abnormalities corresponding to the areas of contrast enhancement were found on unenhanced T2- and T1-weighted MR images. In non-meningeal tumors only 2/24 cases showed a "meningeal sign". In conclusion, with a sensitivity of 52% and a specificity of 92%, the demonstration of the "meningeal sign" improved the differential diagnosis of intracranial meningiomas in contrast-enhanced MR imaging.

Adult↗
PubMed1990

Intracranial meningiomas. Comparison of plain and contrast-enhanced examinations in CT and MRI.

Fifty patients with intracranial meningiomas underwent plain and contrast-enhanced examinations with CT and MRI. Each of the MR studies consisted of three plain (T1, proton density and T2-weighted) and a post-contrast series (0.1 mmol Gd-DTPA/kg body weight). All techniques (plain CT, plain MRI, contrast-enhanced CT, contrast-enhanced MRI) proved to be highly efficient as regards tumour detection: depending on the technique, an intracranial lesion was demonstrated in 47-50 cases. The image contrast was assessed as good or excellent in 21 cases having plain CT and in 33 cases having plain MRI, but in 46 and 50 of the contrast-enhanced CT and MRI studies respectively. Adequate tumour delineation was achieved in 18 cases with plain CT, in 35 cases with plain MRI and in 46 and 50 cases of the contrast-enhanced CT and MRI examinations. The contrast-enhanced studies proved to be superior to the plain CT and MRI studies as regards image contrast and tumor delineation. Because of the methodological advantages of the MRI technique, contrast-enhanced MRI was judged to be slightly superior to contrast-enhanced CT.

Adult↗
PubMed1990

Multiple slice FLASH imaging: an improved pulse sequence for contrast enhanced MR brain studies.

A multisclice gradient echo sequence (FLASH) was compared with a conventional spin-echo (SE) technique with regard to its value for contrast enhanced brain studies. In 50 patients with contrast enhancing intracranial lesions, MR studies (0.5 Tesla MR tomograph) were performed with SE images (SE 400/30; four images/3.4 min) and FLASH scans (FLASH 315/14, 90 degrees; 15 images/1.4 min) before and after Gd-DTPA. Based on visual and quantitative assessment diagnostic results of postcontrast SE- and FLASH images were equivalent with respect to contrast enhancement, lesion/brain-contrast, lesion/edema-contrast, and lesion delineation. Although image quality generally was excellent on postcontrast FLASH images, susceptibility artifacts were more severe on FLASH scans than on SE images. However, with the exception of postoperative patients with artifacts due to metal remains, diagnostic information was not decreased by artifacts on postcontrast FLASH images. In conclusion, because of the clearly higher efficiency of the multisclice FLASH technique, this pulse sequence offers the opportunity to speed up contrast enhanced brain imaging.

Adult↗
PubMed1990

Focal-unilateral accentuation of changes observed in the early stage of Creutzfeldt-Jakob disease.

We report on a 67-year-old male patient with progressive right-sided hemiparesis predominating in the arm and right-sided myoclonias. The EEG showed periodic delta activity in the left hemisphere. The patient died of pulmonary embolism 10 weeks after the onset of the symptoms. The neuropathological examination was indicative of Creutzfeldt-Jakob disease: distinct spongiform changes, nerve cell loss and proliferation of astroglia in the left hemisphere were found; in the right hemisphere, however, only a few circumscribed spongiform foci were seen. There was a clear correlation between the unilateral predominance of the EEG abnormality and neuropathological changes. The hypothesized spread of infection along commissural projection pathways is supported by this pattern of lesions.

Aged↗
PubMed1990

[Mini-septoplasty--for function and form].

Septoplasty often provokes aesthetic and unaesthetic sequelae of the anterior third and the tip of the nose. In a retrospective study of 100 patients these changes and sequelae have been analysed preoperatively and six months postoperatively. The postoperative changes are systematically referred to the surgical steps described in the operation notes. The dynamics of sculpturing the anterior border of the quadrangular cartilage, the effects of septal realignment, the influence on the tip support structures are outlined. The importance of minimum surgical touch is stressed. Examples of aesthetic and unaesthetic sequelae caused by functional septoplasty are presented.

Esthetics↗
PubMed1990

[Cerebral and meningeal manifestations of AIDS: sensitivity of CT and T2-weighted MRT (129 patients)].

We studied 129 AIDS patients with suspected or proved intracranial manifestations of the disease. The purpose of this study was to compare the diagnostic sensitivity of unenhanced and contrast enhanced CT and unenhanced T2-weighted MR. In 35/129 patients CT and MR findings were normal. In 37/129 patients equivalent findings were obtained with both methods. Although CT and MR demonstrated intracranial pathology in 25 cases, MR was clearly superior. Six of these cases had solitary lesions in CT, while MR demonstrated multiple lesions. MR detected more foci than CT. In 24 patients with normal CT, MR detected intracranial manifestations of AIDS, namely solitary lesions in 8, multiple lesions in 12 and meningeal alterations in 4 patients. In only 8 patients with normal MR findings, CT revealed pathological contrast enhancement in 2 and parenchymal calcifications in 6 patients. Thus, in 20% of our patients MR but not CT was diagnostic. In another 20% MR provided additional diagnostic information. In conclusion, MR is recommended as the imaging modality of choice in AIDS patients with non-conclusive cranial CT.

Acquired Immunodeficiency Syndrome↗