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Biomedical subjects

M A van Buchem

Publications and source records attributed to M A van Buchem.

61 records · Page 4Linked to original sources
PubMed1988

Leucostasis, an underestimated cause of death in leukaemia.

Massive sludging of leukaemic cells in blood vessels is a frequent and often lethal complication of leukaemia. In a retrospective clinicopathological study on the causes of death in 52 patients with acute myeloid leukaemia and myeloproliferative disease, pulmonary leucostasis was found in 40% of the patients. In many of these patients the vessels of the heart, brain and testes were also involved. In search for signs and symptoms specific for leucostasis, the clinical records of the 21 patients with leucostasis (the study group) were compared to those of 20 patients without leucostasis (the control group). Dysfunction of the organs most affected by leucostasis, namely lungs, heart and brain, was found more often in the study group than in the controls, but the combination of unexplained fever with cardiopulmonary and/or central nervous system failure occurred almost exclusively and in half of the patients with leucostasis. Leucostasis occurs predominantly, but not exclusively, in patients with high leucocyte counts, and especially, but again not exclusively, when the leucocyte counts rise sharply.

Adult↗
PubMed1987

Pulmonary leukostasis: radiologic-pathologic study.

The terminal chest radiographs of ten patients with pulmonary leukostasis were correlated with the autopsy findings. In six patients, no abnormalities attributable to leukostasis were seen on chest radiographs. In four patients, diffuse alveolar consolidations were caused by alveolar edema following leukostasis. Leukostasis should be considered in leukemia patients with severe dyspnea who have normal chest radiographs or diffuse alveolar edema.

Cause of Death↗
PubMedDate not supplied

Ultrafast scan magnetic resonance in prenatal diagnosis.

OBJECTIVE: To determine whether magnetic resonance (MR) can give additional information in prenatal diagnosis of congenital anomalies, when the ultrasound (US) analysis is not conclusive. METHODS: Ultrafast MR scanning examined 39 pregnant women with 41 fetuses in whom US was suspicious of fetal congenital abnormalities. Two techniques were used namely (1) HASTE inversion recovery sequence and (2) FISP 2D. RESULTS: Thirty-nine patients with 41 fetuses were referred for MR because of an equivocal US with regard to brain, spine, skeletal and miscellaneous anomalies. In 1 twin pregnancy, 1 co-twin has not been examined with MRI because of its demise. In 22 of them, additional information was obtained by MR. In 9 the MR was confirmative with the US examination. Four were false negative, comparing with the postnatal diagnosis. Three failed because of maternal claustrophobia and in 2 a diagnosis could not be made. From the 40 fetuses in this study, 38 were examined postnatally by MR, US, plain X-ray or autopsy was performed to confirm the prenatal diagnosis. CONCLUSION: The use of MRI in obstetrics has been limited, until recently. With fast MRI sequences it is not necessary to sedate the fetus. It is advisable in cases where US is equivocal concerning congenital anomalies of the fetus to use MR with fast or ultrafast scan technique, especially when the central nervous system is concerned.

Brain↗
PubMedDate not supplied

Serial analysis of magnetization-transfer histograms and Expanded Disability Status Scale scores in patients with relapsing-remitting multiple sclerosis.

BACKGROUND AND PURPOSE: Magnetization transfer ratio histogram peak height (MTR-HPH) has been shown to correlate with macroscopic and microscopic brain disease in patients with multiple sclerosis (MS). We studied the changes in MTR-HPH and in Kurtzke's Expanded Disability Status Scale (EDSS) scores over time in a group of patients with relapsing-remitting MS. METHODS: Twenty adult patients with relapsing-remitting MS (four men and 16 women) were followed up for a period of 334 to 1313 days. In all, 86 MR imaging studies of the brain were obtained, and MTR-HPH was calculated for each MR examination by using a semiautomated technique. Changes in MTR-HPH were compared between patients over the study's duration. A neurologist specialized in the care of MS patients assessed the EDSS score for each patient as a measure of clinical disability. RESULTS: Serial MR data showed a subtle but significant decline in MTR-HPH with time. No significant changes in EDSS scores were noted over the same period. CONCLUSION: Patients with relapsing-remitting MS have a significant progressive decline in normalized MTR-HPH, which is independent of EDSS score. MTR-HPH measurements can be used to monitor subclinical disease in patients with relapsing-remitting MS over a short time frame of 1 to 4 years. This parameter might be applied in future therapeutic trials to assess its usefulness.

Adult↗
PubMedDate not supplied

Comparison of T2 lesion volume and magnetization transfer ratio histogram analysis and of atrophy and measures of lesion burden in patients with multiple sclerosis.

PURPOSE: The purpose of this study was twofold: first, to compare two different measures of lesion burden in patients with multiple sclerosis (MS), the magnetization transfer ratio (MTR) histogram and T2 lesion volume; and, second, to investigate the relationship between lesion burden and atrophy in patients with MS. METHODS: Thirty patients with MS were examined with MR imaging, including fast spin-echo T2- and proton density-weighted sequences as well as magnetization transfer sequences. The lesion burden in each subject was quantitated by MTR histographic analysis and by a computer-based method for calculating the total volume of lesions on T2-weighted images. Additionally, the CSF volume, the brain parenchymal volume, and the percentage of brain parenchymal volume were determined in all patients by using this method and were compared with measurements in eight control subjects. RESULTS: Significant loss of parenchymal volume was seen in patients with MS as determined by increased CSF volume and decreased percentage of brain parenchymal volume relative to that in age-matched control subjects. An inverse correlation was observed between the peak height of the MTR histogram and T2 lesion volume. T2 lesion volume corresponded positively with CSF volume and inversely with percentage of brain parenchymal volume. The peak height of the MTR histogram corresponded positively with percentage of brain parenchymal volume and inversely with CSF volume. CONCLUSION: MS patients sustain a significant loss of parenchymal volume (atrophy), which corresponds strongly with increasing lesion burden. T2 lesion volume and peak height of the MTR histogram show good correlation, and the peak height of the MTR histogram shows a superior correlation with measures of brain atrophy as compared with measurements of T2 lesion volume, suggesting that the MTR histogram may be a better indicator of global disease burden than is T2 lesion volume.

Adult↗
PubMedDate not supplied

MR outcome parameters in multiple sclerosis: comparison of surface-based thresholding segmentation and magnetization transfer ratio histographic analysis in relation to disability (a preliminary note).

BACKGROUND AND PURPOSES: MR imaging is now widely used to monitor disease progression in patients with multiple sclerosis (MS). The purpose of this study was to explore the relationship between disability status and existing and new MR parameters in MS patients. METHODS: Forty-one patients with clinically definitive MS were studied. MR imaging included T2- and T1-weighted imaging as well as gradient-echo imaging with and without magnetization transfer contrast. We used surface-based thresholding segmentation techniques to obtain T2 and T1 lesion load, T1/T2 ratio, and several magnetization transfer ratio (MTR) lesion load parameters. MTR histographic analysis included measurements of absolute peak height (aHp), relative peak height (rHp), MTR of the peak (MTRp), mean MTR (MTRm), and MTR25, MTR50, and MTR75, relating to the integrals of the histogram at 25%, 50%, and 75%, respectively, of the total area under the curve. All MR parameters were correlated with Expanded Disability Status Scale (EDSS) score, disease duration, and patient's age. RESULTS: Using surface-based thresholding segmentation techniques, we found relatively low correlations with EDSS. T1 lesion load and T1/T2 ratios correlated most strongly. Regarding MTR histographic parameters, EDSS correlated best with rHp but only weakly with others. Similar correlations were found with disease duration, but not with age. CONCLUSION: The best MR correlations with disability were several MTR histographic parameters. Our findings may favor the use of these MR parameters over T2 lesion load to monitor disease progression in patients with MS, findings that should be explored further in longitudinal studies.

Adolescent↗