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C F Kuijper

Publications and source records attributed to C F Kuijper.

6 recordsLinked to original sources

Pre-operative diagnostic biopsy and surgery in paediatric liver tumours--the Amsterdam experience.

AIM: To report 24 years of pre-treatment biopsy and surgical experience in primary liver tumours in children. METHODS: Between 1979 and 2003, 53 children presented with a primary liver tumour of whom 48 who underwent surgical resection were evaluated (two died, two were unresectable, and one was transplanted). Biopsy data, per- and post-operative complications, mortality, and survival were retrospectively reviewed. RESULTS: Benign tumours were diagnosed in eight patients. Surgical resection for a malignant tumour was performed in 40 patients (26 hepatoblastomas (HB), eight hepatocellular carcinomas (HCC) (four had fibrolamellar HCC), three rhabdomyosarcomas (RMS), one neuroblastoma, one non-hodgkin lymphoma (NHL), and one teratoma). Primary resection was performed in one HB, and four HCCs. The cumulative survival without evidence of disease was 73% for HB (median 7 years) and 88% for HCC (median 3.5 years). CONCLUSION: The treatment results are comparable with those of larger international series except for HCC. The existing diagnostic pitfalls in differentiating between the various liver malignancies justify the use of a diagnostic biopsy.

Adolescent↗

Construction of peritoneal venous valves: an experimental study in rats and piglets.

In the search for new techniques to improve venous valve insufficiency, a peritoneal patch with a mesothelial layer on either side was employed in the venous circulation to construct a venous valve de novo. This material was used because of the resemblance in fibrinolytic activity of mesothelial cells to endothelium. The behavior of double-sided flaps of peritoneum was first studied on only one side in the caval vein wall of 10 rats. All veins remained open, and smooth incorporation of the patch into the vein wall was observed. It was therefore decided to use the same material for construction of a cusp blade in the venous circulation. This venous reconstruction was microsurgically performed in 21 rats and 4 piglets. In our hands, intramuscular anesthesia proved superior to intraperitoneal analgesia in rats. For the piglets mechanical ventilation and general anesthesia were used. In 9 of 21 rats a fair or good result was observed, although it did not seem possible to create a fully competent valve with only one cusp blade in the 1.5-mm-diam caval veins. The same fact evolved from the study using four 7-mm-diam piglet veins. All peritoneal flaps in the venous circulation demonstrated rebuilding of their structure, perhaps induced by the relatively exaggerated central venous flow. To our knowledge, this technique has never been used before. It seems to offer many advantages in the venous circulation, where hardly any thrombogenic surface is tolerated in contrast to the arterial circulation. Application in humans is yet premature, but future research may resolve several problems that occurred in this study.

Animals↗

Use of passive function testing in venous insufficiency: a prospective study.

In a prospective study, the results of venous function tests in 19 lower extremities with deep venous insufficiency and in seven control extremities were compared. First, the routine method of asking the patients to exercise their calves was used. Second, cuffs around the calves were rapidly inflated, producing standardized external compression to the calf muscle pump. Our aim was to decrease the influence of artifacts from involuntary muscle efforts and especially to render reproducible results of pressure reduction after passively pumping. The passive function test proved to be the only technique with which a decrease in pressure measured with strain gauges while the patient was in the standing position could significantly be discriminated between diseased and control extremities. Furthermore, the correlation of pressure decrease invasively versus measured noninvasively improved to 37% and thus became significant. Simulating calf venous pump function with the aid of inflatable cuffs is easily applicable in the vascular laboratory. It enables the vascular surgeon to reliably quantify venous recovery time and pressure reduction.

Adult↗

Failure of quantitative venous photoplethysmography to assess venous insufficiency: a prospective clinical study.

The increase of deep venous reconstructive surgery necessitates reliable tests for evaluation of the results, which requires quantization of the expelled volume. This could only be done with invasive measurements, but now it seems possible to calibrate photoelectric cells, and quantize the results. Nineteen limbs of patients with deep venous disease and seven limbs of healthy volunteers were evaluated, with methods known from the literature. In addition to measurements in standing position, these methods were used in the more patient-friendly sitting position. Invasively and noninvasively measured recovery times correlated well in the standing (R = 0.83) and in the sitting position (R = 0.86). However, the quantization of expelled volume did not significantly correlate. Also, the differences between expelled volume of controls and patients were only significant with invasive measurements in the standing position (P = 0.006) as well as in the sitting position (P = 0.004). The differences were not significant with the noninvasive method. In our opinion, photoelectric cells still do not offer an alternative for invasive measurements in the evaluation of results after venous reconstructive surgery.

Adult↗