Biomedical subjects

V Engelbrecht

Publications and source records attributed to V Engelbrecht.

62 records · Page 4Linked to original sources

PubMedDate not supplied

[Follow-up of patients with osteosarcoma and Ewing's sarcoma: a retrospective cost-benefit analysis].

PURPOSE: Determination of the respective roles of clinical investigation, laboratory tests and various imaging techniques in the follow up of children and adolescents with osteosarcoma and Ewing's sarcoma. METHODS: In a retrospective monocenter analysis, charts of 72 patients with osteosarcoma and 47 patients with Ewing's sarcoma were reviewed with respect to ability of different diagnostic methods to detect the relapse, and correlated outcome. RESULTS: In about 25% of relapses, a second remission could be achieved. The most sensitive methods to detect a potentially curable relapse were clinical investigations and chest x-ray in the case of osteosarcoma and chest x-ray and whole body scintigraphy in the case of Ewing's sarcoma. CONCLUSIONS: The different value of diagnostic methods in the follow-up of the two illnesses may be explained by the different tumor biologies and by distinct therapeutic strategies for the treatment of relapses in the two tumor entities. However, an ongoing evaluation of current follow-up strategies is necessary to take into account new therapeutic developments which may shift the importance of certain imaging techniques.

Adolescent↗

PubMedDate not supplied

[MRI follow-up study of aseptic osteonecrosis (AON) in children treated with chemotherapy for malignant diseases].

PURPOSE: The aim of the study was to evaluate by MRI the course of aseptic osteonecrosis (AON) after chemotherapy in children with different malignancies. MATERIAL AND METHODS: Retrospective analysis of 72 MRI studies in 20 children (age: 3.2-18.4 years) presenting with AON after chemotherapy. 8 children were treated exclusively with relief of weightbearing structures, whereas 12 children were additionally treated with hyperbaric oxygen therapy (HBO). Within a range of 3-76 months each patient received 1-6 follow-up exams. The acquired series included multi planar spin-echo as well as fatt-suppressed inversion recovery sequences. The MRI examinations were evaluated by a point-score system (1-6) by two radiologists. RESULTS: AON was most commonly seen in the pedal bones (26.4%), in the hip (23.6%), and in the knee joints (19.4%). Initial findings revealed an average score of 3.1 points. Based upon these initial findings, subsequent analyses show a statistically significant (p < 0.05) score increase of 0.6 score-points. For the observed intervals a: < 6 months, b: 6-12 months, and c: > 12 months the mean scores were: a: 3.3, b: 3.7, and c: 4.5 points. During the observed time period 5 patients were surgically treated in the affected bone areas. CONCLUSION: The majority of chemotherapy associated AON which initially present with advanced findings showed in MRI a progression with frequent destruction of the joint surface over their further course. More discrete forms of AON, especially osteoedema, can be positively influenced by conservative therapy.

Adolescent↗

PubMedDate not supplied

An approach for cure: PEI-chemotherapy and regional deep hyperthermia in children and adolescents with unresectable malignant tumors.

BACKGROUND: Elevated temperatures of 40 - 44 degrees C increase the actions of various anticancer drugs including N-lost derivatives, cytotoxic antibiotics and platinum analoga. In clinical usage thermochemotherapy (TCH) should facilitate surgical resection and ameliorate local tumor control. PATIENTS AND METHODS: From 07/1993 to 12/2002 a total of 39 patients have been enrolled onto a phase-II study (female = 24, male = 15, age 1 - 37.5 years, median 5.2). Among these, 24 patients had extracranial non-testicular germ cell tumors and 15 patients soft tissue or chondrosarcomas. INDICATION: locoregional relapse (n = 29) or unresectable tumor after neoadjuvant chemotherapy (n = 10). Among these two groups, there were ten patients with poor response or progressive disease under primary or relapse chemotherapy. Ten out of the 29 relapse patients had more than one relapse. Tumor site: pelvis (30), abdomen (4), head and neck (2), proximal leg (2) and lumbar spine (1). Thermochemotherapy (TCH): 1800 - 2000 mg ifosfamide/m (2) and 100 mg etoposide/m (2) on days 1 - 4 and 40 mg cisplatin/m (2) on days 1 + 4 combined with regional deep hyperthermia (42 - 44 degrees C, 1 h) on days 1 + 4. RESULTS: In 39 protocol patients a total of 166 TCH courses (332 heat sessions) were applied. 20 patients achieved complete response, and 10 patients achieved partial response. TCH was followed by surgical tumor resection in 28/39 patients and/or radiotherapy in 13/39 patients. At a median follow-up of 27 months, outcome in this high-risk patient population was 22 NED, 3 AWD, 12 DOD, 2 DOC. Five year event free (EFS) and overall survival (OS) for the whole study cohort was 0.39 +/- 0.11 (20/39 patients) and 0.52 +/- 0.11 (25/39 patients), respectively. CONCLUSION: TCH shows substantial therapeutic efficacy and facilitates complete tumor resection in 14 out of 28 operated patients. Multimodal treatment including TCH, surgical resection and/or radiotherapy leads to sustained remission in the majority of patients with locoregional tumor recurrence. The therapeutic effect is most pronounced, if TCH is administered at first relapse. Due to the clinical and histologic heterogeneity the number of patients eligible for TCH is limited. Therefore, a more valid assessment of treatment efficacy can only be made by a matched-pair comparison in cooperation with the clinical registers.

Abdominal Neoplasms↗

PubMedDate not supplied

Cerebellar mutism syndrome.

Since 1980, a growing number of pediatric patients with mutism following posterior fossa surgery have been recognized. This syndrome typically affects children and in rare cases young adults who become mute one or two days after tumor operation but do not show disturbances of consciousness or language comprehension. The disorder persists for 1 to 4 months. The pathogenesis is still unknown. Of 21 children who underwent surgery for large posterior fossa tumors between 1991 and 1995, 6 developed cerebellar mutism. Histologically the tumors were classified as astrocytoma WHO grade I, astrocytoma WHO grade II and ependymoma WHO grade III in one case and medulloblastoma WHO grade IV in three cases. Besides the clinical course, intraoperative findings and CT or MRI data are evaluated and discussed considering possible etiological hypotheses. Our own experience and also literature reviews suggest that the lesion of the cerebellar hemispheres might be the most important one of multiple factors causing cerebellar mutism. Generally the syndrome is transient. The diagnosis should not delay adjuvant therapy in patients with a malignancy.

Adolescent↗

PubMedDate not supplied

MRI of the brain in Wilson disease: T2 signal loss under therapy.

Repeat examinations in a de novo patient with Wilson disease revealed an expansion of decreased signal intensities in the basal ganglia on T2-weighted imaging after initiation of copper trapping therapy. Since marked clinical improvement was associated with continued urinary copper excretion, iron depositioning in exchange for copper might explain these findings.

Adult↗

PubMedDate not supplied

Aseptic osteonecrosis in children with acute lymphoblastic leukemia.

Joint destruction caused by aseptic osteonecroses (AONs) is a severe complication in acute lymphoblastic leukemia (ALL). Here, factors were determined that influence the occurrence and clinical course of AON in ALL patients. Clinical data of 121 patients were correlated with the occurrence of AON. Magnetic resonance imaging was performed in patients with bone pain. Areas of AONs were correlated with the clinical course of AON. Ten patients presented with clinical symptoms of AON and 9 of 10 patients were graded as high-risk ALL compared with 46 of 111 patients without AON (chi 2, P < .05). In 10 ALL patients 66 AONs were identified by MRI. In some patients up to 14 different AON sites were observed. The courses of AONs varied in individual patients, suggesting that necrosis-specific factors might be responsible. A size above 900 mm2 was significantly associated with progressive AON (P < .01). The more intensive treatment regimen in high-risk ALL patients might contribute to the development of AON. The clinical course of AON, however, is determined by necrosis-specific factors such as a large size. These data could help in developing therapeutic strategies for the prevention of progressive AON.

Adolescent↗

PubMedDate not supplied

High-dose intravenous therapy with 7S immunoglobulins in autoimmune endocrine ophthalmopathy.

OBJECTIVE: Endocrine ophthalmopathy is an autoimmune disorder of the retroorbital space tissues which is generally associated with thyroidal Graves' disease. Its pathogenetical aspects, clinical appearance and diagnostic procedures are reviewed. Therapeutic options include both established and more experimental approaches. Increasing use of intravenously administered immunoglobulin preparations has been noted in a variety of autoimmunologically mediated diseases. We report preliminary data of an observational trial on high-dose immunoglobulin treatment including 10 patients suffering from thyroid eye disease. METHODS: Ophthalmopathy which had not been present for longer than 12 month and Graves' disease with an euthyroid metabolic state at the time of the investigation were the inclusion criteria. Therapy was commenced with a high initial immunoglobulin dose of 20 g/d over a period of five days, and 4 further doses of 20 g each were administered at intervals of 4 weeks. RESULTS: No significant decrease was found in the clinical ophthalmopathy index and in thyroid-specific autoantibody levels. The eye muscle index, determined radiologically by orbital computed tomography as a parameter for inflammatory eye muscle involvement, also did not change significantly during therapy. CONCLUSION: In contradiction to previous reports, our results do not at present allow a general recommendation of high-dose immunoglobulin treatment in thyroid-related ophthalmopathy. Immunoglobulin therapy might be effective in selected patients, but criteria for selection have to be defined.

Adult↗

PubMedDate not supplied

Age-dependent changes in magnetization transfer contrast of white matter in the pediatric brain.

BACKGROUND AND PURPOSE: It is unknown to what extent magnetization transfer contrast (MTC) in white matter of the brain changes during myelination. The goal of this study was to measure the age-dependent changes of MTC in different regions of the pediatric brain and to evaluate their relation to T2 relaxation times. METHODS: Seventy children aged 1 week to 80 months without evidence of organic brain disease underwent MR imaging of the brain. A double-echo spin-echo (SE) sequence and an SE sequence with and without an off-resonance pulse were performed in the axial orientation. Using paired images, we calculated MTC ratios in 13 predefined regions of the brain and compared them with the T2 relaxation times measured in the same areas. Regression analysis was performed for both parameters to evaluate age dependency. RESULTS: MTC in white matter increased during myelination from a range of 13% to 19% to a range of 34% to 37%. At the same time, T2 relaxation times decreased from a range of 115 to 160 milliseconds to a range of 60 to 70 milliseconds after myelination. For both MTC and T2 relaxation times, age dependency could be expressed by a monoexponential function. CONCLUSION: A strong positive correlation exists between MTC ratios and the degree of myelination in the pediatric brain, and an inverse correlation exists between MTC and T2 relaxation times. Fast proton relaxation within macromolecules in the myelinated white matter and subsequent MT may be the most important reason for the decreasing T2 relaxation time of white matter during brain myelination.

Aging↗