Biomedical subjects

O Sabri

Publications and source records attributed to O Sabri.

76 records · Page 5Linked to original sources

PubMed1995

[Effect of morphological changes on perfusion and metabolism in cerebral microangiopathy. A comparison of PET, SPECT, and magnetic resonance imaging findings].

51 patients with cerebral microangiopathy were studied with MRI, 18FDG-PET, and 99mTc-HMPAO-SPECT. Exact morphological correlation of MRI-findings to functional data from PET and SPECT was obtained by a special head holder system applied to the patient's head. Patients with less than four lacunar infarctions (LI) and without or only slight deep white matter lesions (DWML) in MRI showed no significantly changed parameters (rMRGlu, rCBF) compared to patients with four or more LI and severe DWML. Patients with medium to severe outer and inner brain atrophy showed significantly lower rMRGlu and rCBF values in both cortex and white matter than patients with no to only slight atrophy. Thus, in patients with cerebral microangiopathy only atrophy and not the presence of LI and DWML is associated with a significant reduction of rCBF and rMRGlu.

Brain↗

PubMed1995

[Comparison of relative 18FDG uptake with metabolic rate (MRGlucose) in the myocardium in CAD, classified by 99m-Tc-MIBI].

AIM: Are i) typical patterns of perfusion/metabolism (match, mismatch), gained from relative 99mTc-MIBI vs relative 18FDG uptake (normalized to the perfusion maximum) obtainable also vs absolute MRGlu and is ii) rMRGlu in the segment of maximum perfusion (MIBI = 100%) within the normal range for all degrees of coronary artery disease (CAD)? METHODS: In 55 non-diabetic patients with CAD, relative myocardial perfusion (99mTc MIBI SPECT at rest) and relative 18FDG uptake (PET after glucose load) were used to separate for various flow/metabolism constellations. In addition, regional glucose metabolic rate (rMRGlu in mumol/100 g/min; dynamic-graphic analysis from Gambhir/Patlak) was determined in 13 segments of the left ventricle each (i.e., in a total of 715 segments). RESULTS: rMRGlu revealed wide standard deviations (up to 51%). It decreased from normal (52.7 +/- 27.3 mumol/100 g/min), mismatch (45.3 +/- 17.3) and intermediate (35.2 +/- 12.4) to match ("non viable"; 26.7 +/- 13.3) significantly (p < 0.01). In 26% of the perfusion maxima, MRGlu was < 40 mumol/100 g/min. Out of these, only in five patients (of 28) with 3-vessel disease, it was even smaller (< 30 mumol). In three out of the latter, glucose blood levels were below euglycemia. CONCLUSION: rMRGlu in CAD revealed an identical perfusion/metabolism pattern as relative 18FDG uptake. Thus, the higher efforts employed to compute rMRGlu do not yield diagnostic advantage. The segmental perfusion maximum, used for normalization of relative 18FDG uptake (100% MIBI uptake = 100% FDG uptake) was reliable in euglycemic patients even with 3-vessel disease.

Biological Transport↗

PubMed1994

A method of correlating and merging cerebral morphology and function by a special head holder.

A method is introduced which records and correlates topographically identical morphological and functional image data by means of a special head holder system which is adaptable to different modalities (MRI, PET, SPECT). It is based on a commercially available thermoplastic headmask. A thermoplastic form is used to mold an individual headmask (time required: 7 min) for all modalities providing a fixation of the patient during acquisition. This method guarantees an exact repositioning and therefore the same slice orientation of the images. The in-plane correlation is performed by adapting standard offset parameters determined with a homogeneous head phantom. By fusion (merging) of the brain outline contours or images themselves the accuracy was tested in MRI vs. PET resp. SPECT (transaxial accuracy: < or = 2.0 mm, axial: < or = 3.0 mm in patients with MRI-slice thickness of 6.0 mm).

Brain↗

PubMedDate not supplied

The concept of the GPOH-HD 2003 therapy study for pediatric Hodgkin's disease: evolution in the tradition of the DAL/GPOH studies.

Today it is possible to cure more than 90 % of children and adolescents with Hodgkin's disease with a combination of radiotherapy and chemotherapy. Since the DAL-HD 82 study, the main scientific focus has been on avoiding late effects such as the OPSI syndrome, late complications involving the heart, lungs, thyroid and/or gonads particularly sterility in men and premature onset of menopause in women, and the prevention of secondary malignancies. The GPOH-HD 2003 study will introduce FDG-PET to the initial diagnostic program and the assessment of response to therapy in order to evaluate further possibilities for reducing therapy. In this context, the central review of all clinical and radiological findings, systematically done since the DAL-HD 90 study, will be increasingly relevant in maintaining standardised stage classification and therapy group assignment which was established by the preceding studies. Continuing in the direction of the earlier studies, the indications for radiotherapy will be restricted even further. In the early stages (treatment group 1) patients with CR or a negative FDG-PET at the end of chemotherapy will receive no radiotherapy in order to reduce the risk of a secondary malignancy. In a randomized comparison, procarbazine will be replaced by dacarbazine in the COPP cycles to determine whether sterility in men and premature onset of menopause in women can be avoided by elimination of procarbazine while retaining the same clinical efficacy. Finally, relapse therapy is to be tailored according to the time of relapse, the initial therapy group, and the patient's response to the relapse therapy with more patients receiving autologous transplantation in order to further improve the results of relapse treatment.

Antineoplastic Combined Chemotherapy Protocols↗