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C H Wittens

Publications and source records attributed to C H Wittens.

34 records · Page 2Linked to original sources
PubMed1995

Assessment of stenoses in the aortoiliac tract by calculation of a vascular resistance change ratio before and after exercise.

OBJECTIVES: Intraarterial pressure measurement is the most reliable method to assess haemodynamically significant stenoses in the aortoiliac tract. We have tried to develop a simple and quick, non-invasive method to assess stenoses of this type. DESIGN: Prospective semi-blinded clinical study. METHODS: It was postulated that a haemodynamically significant aortoiliac tract stenosis would result in a lesser degree of vascular resistance decrease after vasodilatation, compared to patients only suffering from femorodistal stenoses. We approximated vascular resistance by: (brachial pressure-ankle pressure)/femoral artery mean Doppler velocity. By dividing vascular resistance at rest by vascular resistance after exercise, we calculated the Resistance Change Ratio (RCR). PATIENTS AND RESULTS: In 34 patients (50 legs) with arterial stenoses, the pressure gradient over the aortoiliac segment was compared to the RCR. Legs were divided in three groups: group 1 consisted of 22 legs that showed a pressure gradient > 10 mmHg at rest; group 2 showed a pressure gradient > 10 mmHg after papaverine; group 3 showed a pressure gradient of 10 mmHg or less. The median RCR was: 0.74 (range: 0.23-4.04) for group 1, 0.71 (range: 0.36-1.80) for group 2 and 0.93 (range 0.36-2.06) for group 3. There was no significant difference between the groups (p = 0.19). CONCLUSION: The RCR could not be used to accurately detect stenoses in the aortoiliac.

Aorta, Abdominal↗
PubMed1995

A new "closed" in situ vein bypass technique results in a reduced wound complication rate.

OBJECTIVES: This prospective randomised multicentre trial was conducted to test whether a new "closed" technique for in situ vein bypass would result in a lower frequency of wound complications, without negative effects on patency rates and without an intolerable increase in residual arteriovenous fistulae compared to the conventional "open" technique. METHODS: We have developed a new "closed" technique using a co-axial catheter embolisation system for intra-operative coil embolisation of side branches, in order to avoid long incisions. PATIENTS: In four centres and 95 patients, 97 in situ bypasses were performed: 47 "closed" and 50 "open". Randomisation was stratified for below knee femoropopliteal bypasses (60) and femorocrural bypasses (37). Indications were disabling intermittent claudication (29), restpain (26) or ulcers and/or necrosis (42). RESULTS: Postoperative mortality was 2% (one in the "closed", one in the "open" group). A total number of 16 (34%) wound complications (grade 1, 2 and 3) occurred in the closed group compared to 36 (72%) in the open group (p < 0.05). Deep wound complications (grade 2) occurred in six patients (13%) of the "closed" group, compared to 15 (30%) in the "open" group. In both groups, three patients (6%) developed deep wound complications including the bypass area (grade 3). In the "closed" group, 20 patients needed additional treatment for arteriovenous fistulae, compared to four in the "open" group. One-year patency rates did not show a statistically significant difference: primary patency rates were 65% and 61% and secondary patency rates were 86% and 76% respectively for the "closed" and "open" group. CONCLUSION: These results indicate that a "closed" technique reduces wound complication rate, without negative effects on the short term patency rates. The "closed" technique results in an increased number of postoperative treatments for residual arteriovenous fistulae.

Aged↗
PubMed1995

Subfascial endoscopic ligation in the treatment of incompetent perforating veins.

OBJECTIVES: To assess the technique of subfascial endoscopic ligation of incompetent perforatory veins by use of a mediastinoscope. DESIGN: Prospective open clinic study. SETTING: Two Departments of Surgery. MATERIALS AND METHODS: Thirty-eight consecutive patients (40 legs) with recurrent or protracted venous ulceration of the lower leg were treated. Through a short, transverse incision of the skin and fascia in the proximal 1/3 of the lower leg a mediastinoscope (length 18 cm, diameter 12 mm) is inserted after which the perforating veins are ligated by haemoclips under direct vision. MAIN RESULTS: All legs showed signs of incompetent perforating veins by clinical examination, confirmed with continuous wave ultrasonography and in 31 legs there was associated deep vein incompetence. Sixteen patients had active ulceration at the moment of operation and 22 had a history of recent or recurrent ulceration. One patient developed an inflammatory reaction at the wound and in two legs a subfascial infection occurred, necessitating surgical drainage. No postoperative mortality was seen. All 16 ulcers healed within 2 months (mean: 34 days; range: 21-55 days). During a mean follow-up of 3.9 (range: 2-5) years only one out of 38 patients (2.5%) developed a recurrent ulcer. CONCLUSIONS: Subfascial endoscopic ligation of incompetent perforating veins by use of a mediastinoscope is a relatively simple technique with a low postoperative complication rate and a low recurrent ulcer rate which makes it a valuable method for treating incompetent perforating veins.

Bandages↗
PubMed1994

A new "closed" in situ vein bypass technique.

AIM: We have developed a new closed technique using a co-axial catheter embolisation system for intraoperative coil embolisation of the side branches of in situ vein bypass grafts in order to avoid long skin incisions. TECHNIQUE: After completion of the proximal anastomosis, disruption of the valves and completion of the distal anastomosis, the catheter is introduced via a proximal side branch of the greater saphenous vein. Under fluoroscopic control the side branches are identified, selectively catheterised and an embolisation coil is positioned in each side branch. PATIENTS: In 14 patients (eight men, six women), 16 in situ bypasses were performed (12 below knee femoro-popliteal, four femoro-crural). RESULTS: Once mastered the embolisation procedure took less than 1 hour. In four cases persistent arteriovenous fistulae had to be treated in the postoperative period. Two major wound complications occurred and there were three early failures. One late failure occurred due to a rupture of the venous bypass 6 weeks postoperatively. The remaining 12 bypasses are patent, with a median follow-up of 16 (3-26) months. CONCLUSION: These preliminary results suggest that the "closed" technique is feasible and that long term occlusion of AV-fistulae can be achieved without ligation via incisions.

Arteriovenous Shunt, Surgical↗
PubMed1993

[Good results of subfascial endoscopy as treatment of communicating vein insufficiency].

Incompetent communicating or perforating veins are often responsible for recurrent varicose veins with skin changes at the lower leg, especially in the postthrombotic syndrome. Subcutaneous and subfascial surgical explorations carry a 35% complication rate. We used a new endoscopic technique to locate and ligate communicating veins with the objective to decrease this complication rate. Through a short skin incision on the anteromedial side of the proximal 1/3 of the lower leg the fascia is incised over 2 cm and the subfascial space opened by finger dissection. A mediastinoscope (length 18 cm; diameter 12 mm) is inserted and pushed down beneath the fascia to the level of the malleolus. Under direct vision the communicating veins crossing this space are located and ligated with haemoclips. In 48 patients, 15 male and 33 female, with a mean age of 53 (22-73) years, 54 legs were treated: 40 legs showed recurrent varicose veins, due to incompetent communicating veins with severe skin changes and ulcers, and 14 had primary varicosis. All patients complained of fatigue and pain. In 49 legs (44 patients) relief of preoperative complaints was obtained and in 5 (4 patients) there was no change. Two indurated wounds and 1 dehiscent wound were treated conservatively. One patient, operated on both legs, developed a severe subfascial infection on both sides necessitating a reintervention. The advantages of the subfascial endoscopic technique, a fast operative procedure, fewer postoperative wound infections (9.3%), a good cosmetic effect, and a low (2.5% after 3.8 years) recurrent ulcer rate make it a valuable new method for treating incompetent communicating veins.

Adult↗
PubMed1992

Winner of the ESVS Prize 1991. European Prospective Randomised Multi-centre Axillo-bifemoral Trial.

In vitro and in vivo studies revealed significantly better haemodynamic properties for a newly designed axillo-bifemoral bypass graft, with a flowsplitter at the bifurcation. In order to analyse the clinical relevance of these improved haemodynamic properties a prospective randomised clinical trial was performed. The patency rates of two different axillo-bifemoral bypass grafts, differing only in the configuration of the bifurcation: one with a contralateral branch at an angle of 90 degrees and one with a flowsplitter, were analysed. In 19 centres, 117 patients were randomised, 59 receiving a prosthesis with a flowsplitter, and 58 a prosthesis with a 90 degrees bifurcation. Indications and risk factors were equally distributed in both groups. Final analysis after 3 years with a mean follow-up of 12 months (range 3-36 months) showed that the prosthesis with a flowsplitter had a significantly better patency rate after 2 years of 84% compared to the patency rate of the prosthesis with a 90 degrees-angled bifurcation of 38% (log-rank test, p less than 0.0001). These data were not significantly influenced by the indication for the operation, associated risk factors (e.g. diabetes mellitus, hypertension or myocardial infarction), outflow tract or anti-coagulant therapy. Other endpoints such as death and graft infection did not differ significantly.

Aged↗
PubMed1991

Accuracy of computed tomography of the mediastinum in bronchogenic carcinoma.

The results of preoperative CT-scanning were compared with the pathological findings in lymph-nodes taken at mediastinoscopy and/or thoracotomy in 144 patients to determine the accuracy of CT of the mediastinum in staging lung cancer. Ninety-nine patients had squamous cell carcinoma, 31 adenocarcinoma, nine undifferentiated large-cell carcinoma and five patients had carcinoma of a mixed cellular type. Mediastinoscopy was done in 105 patients and thoracotomy in 126. The results of our study showed that CT is useful to select patients for mediastinoscopy for T1 lung cancer in general because of a negative predictive value of 98 per cent. CT is also useful for T2 and T3 lung cancer located at the left lower lobe or the right upper, middle or lower lobe (negative predictive value 87%). However, mediastinoscopy is always necessary in patients with T2 or T3 lung cancer at a main bronchus or a left upper lobe because of the low negative predictive value (58%). Preoperative aorto-pulmonary window evaluation is not recommended in case the CT-scan for the aortopulmonary window is negative because of a reasonable negative predictive value (81%).

Carcinoma, Bronchogenic↗
PubMed1990

The imaging quality of angiodynography in the ilio-femoral tract.

The imaging quality of angiodynography (Quantum; Philips) in the ilio-femoral tract was compared with uniplanar angiography. One hundred ilio-femoral tracts were investigated with both translumbar conventional angiography and angiodynography. The ilio-femoral tract was divided into five parts; proximal and distal common iliac, proximal and distal external iliac and common femoral. Stenosis was scored from 0-24, 25-49, 50-74, 75-99 and 100% and the lengths of those of 25% or more were measured in centimeters. Because the thickness of the subcutaneous fat layer decreases the depth range (normally 11.5 cm) of the 5.0 MHz transducer it was also measured in centimetres. The results showed that a significantly larger number of vessels were not seen (especially the common iliac) with an increasing thickness of the subcutaneous fat. The results based on the real-time imaging quality alone of angiodynography showed a reasonable accuracy of 83.9% when detecting stenoses graded from 0-24, 25-49, 50-74, 75-99 up to 100%. The clinically more important discrimination between a haemodynamically important stenosis of more than 50% showed a sensitivity of 88% and specificity of 98% on visual information alone. By integrating the peak velocity measurements to the results, this sensitivity rose to 95% and the specificity became 99%. The correlation in length was within a range of 1 cm in 94% and within 1-2 cm in 6% of the stenoses. In conclusion, angiodynography is a reliable technique for investigating the ilio-femoral tract.

Angiography↗
PubMed1990

Intraluminal Miller-Abbott tube stenting as treatment and prophylaxis of recurrent intestinal obstruction.

Chronic recurrent intestinal obstruction due to massive adhesions after abdominal surgery is a complication that is difficult to treat. The records were studied of 25 patients with acute intestinal obstruction due to massive adhesions. Since conservative measurements were unsuccessful, the patients were treated with internal intestinal splinting by means of a Miller-Abbott tube. These 25 patients underwent a total of 72 operations, 36 were performed for mechanical obstruction. Conservative treatment alone was effective during 25 admissions. The complaints of the patients lasted five years on an average. After lysis of adhesions the Miller-Abbott tube was introduced either via the nose, via a gastrostomy or via an enterostomy. The tube was left in situ for three weeks and then gradually withdrawn. There was no hospital mortality. There was one postoperative complication: a tube had to be removed under general anaesthesia. Long-term follow-up of the patients varied from 4.5 to 19 years with a mean of 11.3 years. One patient with recurrent intestinal obstruction due to adhesions, required surgical intervention after one year. A second patient with Peutz-Jeghers syndrome needed surgery because of an intestinal adenoma after six years. The mean symptom-free interval was 11.1 years in the cured patients.

Female↗
PubMed1986

Traumatic intrapericardial diaphragmatic hernia.

Fifty-eight cases of traumatic intrapericardial diaphragmatic hernia were found in the literature and another delayed case added. The majority of patients presented after traffic accidents, with cardiopulmonary or abdominal symptoms. Most of the associated lesions to the bony skeleton were on the left side of the body. Chest X-rays and contrast studies, CAT scans, and echocardiography were helpful in establishing the diagnosis. We do not consider pneumoperitoneum to be a reliable procedure, nor to be used as a diagnostic aid. In the acute phase an abdominal approach is preferred to the transthoracic approach because the complete diaphragm can be inspected and concomitant abdominal lesions dealt with. Left thoracotomy should not be performed in the acute phase to prevent errors as reported in our patient.

Female↗