Biomedical subjects
Publications and source records attributed to C van de Velde.
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From the literature that was initially searched by electronic databases using the keywords quality, quality control and quality assurance in combination with clinical trials, surgery, pathology, radiotherapy, chemotherapy and data management, a comprehensive review is given on what quality assurance means, the various methods used for quality assurance in different aspects of clinical trials and the impact of this quality assurance on outcome and every day practice.
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OBJECTIVE: To describe the surgical procedure and the results of the indirect hypoglossal-facial nerve anastomosis using a free nerve graft in patients with facial nerve paralysis. This technique leaves the tongue function intact. DESIGN: Prospective study. METHODS: Tongue function was assessed in 39 consecutive patients who underwent this procedure and facial reanimation was assessed in 29 of these patients who had completed at least 24 months follow-up. Facial nerve function was judged using the House-Brackmann (HB) facial nerve grading system. RESULTS: Tongue movements were normal in all operated patients; one patient had mild homolateral atrophy. Initial facial movements occurred on average 7.5 months postoperatively (range 4 to 18 months) in all but one patient. The results were graded HB II in 6 patients (20.9%), HB III in 13 (44.6%), HB IV in 7 (24.1%), HB V in 2 (6.8%) and HB VI in 1 patient (3.4%). Hemifacial synkineses were noticeable but no mass movements or gross hypertonia were observed (as are often present in direct hypoglossal-facial anastomosis). The results of facial reanimation were significantly better in young patients and when a short time interval between paralysis and surgery existed. HB grade II was achieved only if the duration of paralysis was less than 12 months. CONCLUSION: Indirect hypoglossal-facial anastomosis with interposition of a nerve graft allows preservation of tongue function together with good overall facial reanimation, and is therefore to be preferred to the classical direct hypoglossal-facial anastomosis.
Colorectal carcinoma is commonly associated with mutation and overexpression of p53, making this antigen a potential target for immune intervention. We analyzed humoral and proliferative immunity against p53 in the blood of patients with resected primary colorectal cancer. The majority of these patients displayed anti-p53 T helper (Th) immunity in the absence of measurable p53 specific antibody levels. The Th responses were long-lasting since they could be detected up to several years after resection of the primary tumor. In a number of cases the Th responses were highly sensitive, reflected by the recognition of naturally processed p53 protein. Our data argue that boosting of these responses in patients with minimal residual disease through p53-specific vaccination, may be employed for improving the chance of disease-free survival of these patients.
BACKGROUND: The results of indirect hypoglossal facial nerve anastomosis with interposition of a free nerve graft, end-to-end to the periferal facial nerve stump, and end-to-side to the hypoglossal nerve are prospectively evaluated. This technique is supposed to overcome loss of hypoglossal function. METHODS: Tongue function in 39 consecutive patients and facial reanimation in 29 patients who completed 24 months follow-up were assessed. Facial nerve function was judged using the House-Brackmann (HB) grading system. RESULTS: Tongue movements were normal in all operated on patients. Initial facial movements occurred on average 7.5 months postoperatively. The results were graded HB II in 6 (20.9%), HB III in 13 (44.6%), HB IV in 7 (24.1%), HB V in 2 (6.8%) patients, and HB VI in 1 (3.4%) patient. The results were significantly better in young patients and when a short time interval between paralysis and surgery existed. CONCLUSIONS: Indirect hypoglossal-facial anastomosis is the preferred technique in most patients for whom the classical direct hypoglossofacial anastomosis is indicated.
BACKGROUND: Perioperative blood transfusions are reported to be related to cancer recurrence and reduced survival. Different underlying mechanisms have been proposed, and allogeneic leucocytes in transfused blood have been suggested to contribute to this phenomenon. METHODS: Packed red cells without buffy coat (PC group) were compared with filtered, leucoreduced, red cells (LD group) in a randomized trial of 697 patients with colorectal carcinoma. Five-year survival and cancer recurrence rates were determined, with special emphasis on the location of recurrence. RESULTS: The intention-to-treat analysis showed a survival rate of 63.6 per cent in the PC group and 65.3 per cent in the LD group (P = 0.69), with recurrence rates of 27.8 and 27.9 per cent respectively. The observational analysis showed a significant difference in survival between transfused and non-transfused patients (59.6 versus 72.9 per cent; P < 0.001). The difference in cancer recurrence rate between transfused and non-transfused patients was not statistically significant (29.8 versus 24.3 per cent; P = 0.13). Local recurrences were more frequent in transfused than non-transfused patients (11.9 versus 7.6 per cent; P = 0.09). CONCLUSION: Leucocyte depletion of perioperative transfused blood has no effect on long-term survival and/or cancer recurrence. Perioperative blood transfusions are associated with impaired survival, but not with cancer recurrence. The slight increase in local recurrence rate in transfused patients appears to be related to complicated, in particular rectal, surgery.
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CT was performed in a series of 150 consecutive clinically diagnosed meniscal lesions of the knee. Six to 12 contiguous slices, each 1 mm thick, were obtained starting from the tibial plateau and proceeding cranially to the intercondylar fossa. The medical imaging team was not informed of the medical history of the patients nor of the relevant clinical diagnosis. Arthroscopic findings were subsequently correlated with the CT findings. With the arthroscopic diagnosis defined as correct, a CT sensitivity rate of 80% was obtained. The specificity of the test was 93%. This study of 75 consecutive meniscal tears was designed to evaluate arthroscopic meniscal suturing using an inside-out technique.
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