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H Henkes

Publications and source records attributed to H Henkes.

At least 55 records · Page 3Linked to original sources

[Magnetic resonance of brain involvement in progressive facial hemiatrophy (Romberg's disease). Reconsideration of a syndrome].

UNLABELLED: Progressive facial hemiatrophy (PFH) is a sporadic disease of unclear etiology, characterized by shrinking and deformation of one side of the face. Reports and interpretations of CNS involvement in PFH, as deduced from the occurrence of seizures in some patients and documented by pneumoencephalography and CT findings in small series of patients, are contradictory. We examined three female patients with PFH, one with partial epilepsy, with the view to gaining further insight into the pathogenesis of the disease. METHODS: Routine MR examinations of the head and face were performed. RESULTS: Only the patient with epilepsy showed pathological findings, confined to the cerebral hemisphere homolateral to the facial hemiatrophy, and including monoventricular enlargement, meningo-cortical dysmorphia and white matter changes. CONCLUSIONS: The MR morphology, and corresponding neuroradiological and histopathological findings disclosed by a review of the literature, indicate that homolateral hemiatrophy is a typical finding for a subgroup of PFH patients, but do not support the model of a simple or nutritive atrophic process. We reconsider chronic localized meningo-encephalitis with vascular involvement as possible underlying cause of the occasional brain involvement in PFH.

Adult↗

[Magnetic resonance angiography of intracranial aneurysms after subarachnoid hemorrhage].

Magnetic resonance angiography is now commercially available for a variety of scanners and is being increasingly applied in the diagnosis of cerebrovascular disorders. Considering the clinical consequences, especially in intracranial aneurysms, studies to determine the sensitivity and specificity of the method are essential. Here we report our experience with a 3D-FISH time-of-flight magnetic resonance angiography protocol in 52 patients who have suffered an acute subarachnoid hemorrhage. In 26 of the 52 patients, conventional angiography identified 31 aneurysms (3-20 mm) that were confirmed during surgery or autopsy. Magnetic resonance angiography correctly identified 28 of the 31 aneurysms (sensitivity 90.3%) and missed one ruptured (3 mm) and two incidental aneurysms (3 mm) in patients with multiple aneurysms. The sensitivity for a ruptured aneurysm was 96%. The 26 patients who suffered subarachnoid hemorrhage without evidence of an intracranial aneurysm on repeated angiography served as a control group. Magnetic resonance angiography revealed no false-positive findings, resulting in a specificity of 100%. In correlation with the literature, we conclude that magnetic resonance angiography is not sensitive enough for the management of acute subarachnoid hemorrhage. However, the method provides important complementary information for definition of the bleeding site in patients with multiple aneurysms. In addition, the calculation of projections not possible with conventional angiography can aid surgical planning. Since only very small aneurysms were missed by magnetic resonance angiography, the sensitivity seems appropriate to screen asymptomatic patients who are at risk for intracranial aneurysms.

Adolescent↗

Blood flow velocity and vasomotor reactivity in patients with arteriovenous malformations. A transcranial Doppler study.

BACKGROUND AND PURPOSE: A large percentage of patients with a cerebral arteriovenous malformation (AVM) show focal neurological signs or have a history of intracranial hemorrhage. The present study used transcranial Doppler sonography to assess the clinical significance of hemodynamic disturbances in the intracranial arteries of patients with an AVM. METHODS: Eighteen patients with untreated AVMs were examined clinically, angiographically, and with transcranial Doppler sonography (blood flow velocity measurement and vasomotor reactivity in all main intracranial arteries). RESULTS: A pathological increase in blood flow velocity (57.6%) and a decrease in vasomotor reactivity (72.7%) were frequently found in AVM feeding arteries. Vasomotor reactivity was also reduced in several nonfeeding arteries both ipsilateral (53.3%) and contralateral (30.8%) to the AVM. AVM size was a poor predictor of pathological transcranial Doppler results. Vasomotor reactivity of arteries ipsilateral to an AVM in patients with a history of hemorrhage was significantly higher (2.10 +/- 1.66% per mm Hg; mean +/- SD) than in patients with no history of bleeding (1.12 +/- 1.48% per mm Hg; P < .05). In patients with focal neurological signs but no history of hemorrhage, the percentage of arteries ipsilateral (100%) and contralateral (63.6%) to an AVM showing a pathological vasomotor reactivity was significantly larger than in nonhemorrhagic patients without focal signs (66.7% and 22.2%, respectively; both P < .05). CONCLUSIONS: Our results suggest two distinct relations between transcranial Doppler results and clinical findings: (1) Relatively normal vasomotor reactivity values in arteries ipsilateral to an AVM indicate a high-pressure AVM with an increased risk of hemorrhage. (2) A strongly pathological vasomotor reactivity in arteries ipsilateral and contralateral to an AVM indicates a low-pressure AVM with a higher prevalence of hemodynamically induced neurological signs.

Adolescent↗

[The MR phase contrast method. Determination of blood flow velocity and flow profile of intracranial arteries].

2D-phase-contrast mapping is a MR method that allows for quantitative measurements of blood flow velocity in intracranial vessels. Using a modified FISP-Sequence with a 1.5 T MR scanner, flow studies were carried out on a phantom. Two matrix sizes (256 x 256 vs. 256 x 512) were compared. In 20 healthy volunteers blood flow velocity and profile of the basal (BA), middle cerebral (MCA), and anterior cerebral artery (ACA) were compared with the corresponding findings of transcranial Doppler (TCD) sonography. 2DPK and TCD yielded equivalent velocity data and profiles of the BA. The blood flow velocity in the MCA determined by 2DPK was lower than the TCD values. Using a 256 x 512 matrix, the acquired data were in better accordance with the TCD findings. Due to significant noise measurements of the ACA and PCA were frequently degraded.

Basilar Artery↗

MR of brain involvement in progressive facial hemiatrophy (Romberg disease): reconsideration of a syndrome.

PURPOSE: To gain further insight into the pathogenesis of progressive facial hemiatrophy, a sporadic disease of unclear etiology characterized by shrinking and deformation of one side of the face. METHODS: We investigated possible brain involvement. MR of the head and face was performed in three female patients with progressive facial hemiatrophy. The central-nervous-system findings were correlated to a clinical protocol and a review of the literature. RESULTS: One patient with epilepsy had abnormal brain findings confined to the cerebral hemisphere homolateral to the facial hemiatrophy. These consisted of monoventricular enlargement, meningocortical dysmorphia, and white-matter changes. CONCLUSIONS: These MR findings, and corresponding neuroradiologic data disclosed by the review, indicate that homolateral hemiatrophy occasionally occurs in a subgroup of patients with progressive facial hemiatrophy. The MR features do not seem consistent with an underlying simple or nutritive atrophic process. We propose chronic localized meningoencephalitis with vascular involvement as a possible underlying cause of the occasional brain involvement in progressive facial hemiatrophy.

Adult↗

Hyperostosis in meningiomas: MR findings in patients with recurrent meningioma of the sphenoid wings.

PURPOSE: We used MR imaging to analyze retrospectively the pattern of hyperostosis occurring concomitantly with recurrent sphenoid wing meningiomas. METHODS: Bone involvement was compared in 12 corresponding CT and MR studies of 10 female patients with sphenoid wing meningiomas recurrence after earlier surgical treatment. Four of these had histologically confirmed meningiomatous infiltration of the bone. RESULTS: All patients had CT findings of localized hyperostosis of parts of the sphenoid wings. MR revealed inhomogeneous areas of slightly increased signal intensity in hyperostotic bone on T2-, proton density- and T1-weighted sequences. In nine of 10 patients, segments of the hyperostotic bone showed different degrees of gadolinium enhancement. CONCLUSIONS: Because earlier studies have revealed high incidences of meningiomatous bone infiltration in sphenoid wing meningiomas, and because infiltration was confirmed in four of our patients, we postulate that the gadolinium enhancement in the area of hyperostosis may be related to meningiomatous bone infiltration.

Adult↗

Spectral power and coherence analysis of sleep EEG in AIDS patients: decrease in interhemispheric coherence.

Fifteen patients aged between 26 and 55 years with the acquired immunodeficiency syndrome (AIDS) and various cerebral manifestations of the disease underwent an all-night sleep electroencephalogram (EEG) registration. The recordings of 15 age-matched volunteers were examined as controls. Sleep stages were determined visually and the following spectral analysis was based on corresponding artifact-free 40-second periods. The sampling rate was 64 second-1, the spectral resolution was 0.25 Hz and the frequency ranged from 0.25-24 Hz. The power density spectra of eight EEG derivations (left and right frontopolar, frontal, central and occipital; reference montage to the ipsilateral Cb electrodes) and the coherence spectra of interhemispheric (interfrontal, interoccipital) and intrahemispheric (frontooccipital, left and right) channel pairs were computed. The power density of the patients in the 11.5-13-Hz frequency range of nonrapid eye movement (NREM) sleep was considerably lower than that of the controls (p < 0.05 and p < 0.01 at left and right frontal derivations, two-tailed Mann-Whitney U test). The power density of rapid eye movement (REM) sleep showed no consistent differences between the two groups. The interfrontal coherence of the whole frequency range below 12 Hz was markedly lower in the patient group. This applied to NREM sleep and also to REM sleep (p < 0.01 and p < 0.001 for different frequency bands between 1 and 12 Hz in NREM and REM sleep). Possible relations to clinical features are discussed.

Acquired Immunodeficiency Syndrome↗

The pattern of regional cerebral blood flow during alcohol withdrawal--a single photon emission tomography study with 99mTc-HMPAO.

Cerebral blood flow was investigated during alcohol withdrawal in 15 male alcoholics by single photon emission computerized tomography with 99mTc-HMPAO and compared with the results of a second study 3 weeks later when all symptoms of withdrawal had disappeared and when the patients had been free of medication for at least 1 week. Slice images were reconstructed parallel to the orbitomeatal plane, and tracer activity was analyzed in 8 regions of interest per hemisphere. During alcohol withdrawal a special pattern of cerebral blood flow distribution could be observed. Relative perfusion was elevated in both inferior temporal regions, whereas it was reduced in the superior temporal region of both hemispheres. The changes of cerebral blood flow distribution did not correlate with neuropsychological findings nor with the severity of withdrawal syndrome.

Adult↗

Acute fracture of the femoral neck: assessment of femoral head perfusion with gadopentetate dimeglumine-enhanced MR imaging.

OBJECTIVE: Evaluation of the perfusion and viability of the femoral head after fracture of the femoral neck is important because the outcome of conservative treatment or joint-preserving surgery is adversely affected by the development of capital osteonecrosis. We evaluated the use of MR imaging, before and after IV administration of gadopentetate dimeglumine, for assessing perfusion of the femoral head in 13 patients with acute fracture of the femoral neck. SUBJECTS AND METHODS: Multiecho (1600/30-240 [TR/TE]) MR images were obtained before contrast administration and gradient-echo (315/14, 90 degrees flip angle) MR images were obtained both before and after contrast administration. MR findings were correlated with findings on superselective digital subtraction angiograms of the vessels supplying the femoral head and with clinical-radiographic follow-up for at least 12 months. RESULTS: Digital subtraction angiography showed impaired blood supply to the femoral head in five patients. On contrast-enhanced MR images of these patients, the femoral head did not enhance and was lower in signal intensity than were the enhancing femoral shaft and neck distal to the fracture and the enhancing femoral head on the unaffected side. In the patients with persistent perfusion, contrast-enhanced MR images showed a uniform increase in signal intensity in the femoral shaft and neck as well as the femoral head; the femoral head on the fractured side showed contrast enhancement similar to that on the healthy side. CONCLUSION: These preliminary results indicate that contrast-enhanced MR imaging may be useful for noninvasive evaluation of femoral head perfusion after fracture of the femoral neck. MR findings also may aid the clinician in deciding between joint-preserving therapy and hip arthroplasty.

Acute Disease↗

[Cerebral manifestations of progressive facial hemiatrophy (Romberg's disease). Nuclear spin tomographic findings and literature review].

Progressive facial hemiatrophy (PFH) is a sporadic disease of unknown etiology. It is characterized by shrinking and deformation of one side of the face. Potential CNS involvement has repeatedly been suspected in some patients, but is still a matter of controversy. In this article we describe the clinical and MR imaging findings of the CNS in three female patients with PFH and present a comprehensive review of the literature. One of three PFH patients had partial epilepsy. MRI showed ventricular enlargement, white matter lesions, flattening of the cortical surface and meningeal adhesions homolateral to the facial hemiatrophy. Two other patients had completely normal intracranial findings. These findings confirm that cerebral hemiatrophy occurs in a subgroup of PFH patients. The MRI pattern, however, does not seem to be consistent with a simple atrophic or malnutritional process. We consider chronic localized meningoencephalitis with vascular involvement as a possible underlying mechanism for the occasional CNS involvement in PFH.

Adult↗

[Endovascular Doppler sonography of intracranial blood vessels. Technical indications and potential applications].

Intravascular Doppler ultrasonography was initially performed with specially designed catheters and was used primarily for cardiological purposes. The recent introduction of a 0.018-in. flexible, steerable guide wire with an integrated 12-MHz piezoelectric transducer (FloWire) has made it possible to use this technique in neuroangiography. This system allows recording of Doppler spectra and determination of blood flow velocities in intracranial vessels after subselective introduction of a standard 3-F microcatheter. The measurement of blood flow velocity in an AVM feeding branch of a middle cerebral artery and the haemodynamic effects of the vasoconstrictive substance sumatriptan on the middle meningeal artery are used to illustrate potential applications of intravascular Doppler ultrasonography in neuroangiography.

Adult↗

[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↗

[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↗

[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↗

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↗

[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↗

[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↗