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M P Jenkins

Publications and source records attributed to M P Jenkins.

14 recordsLinked to original sources
PubMed2005

The value of suction wound drain after carotid and femoral artery surgery: a randomised trial using duplex assessment of the volume of post-operative haematoma.

BACKGROUND: The use of vacuum suction drains after carotid endarterectomy (CEA) and groin dissection for arterial reconstruction surgery remains controversial. A large multicentre prospective randomised trial would be needed to show any difference if clinical end points (infection and haematoma) are used. Therefore, we conducted a study to evaluate the value of wound drainage using accurate duplex measurement of haematoma expecting a 25% difference in volume between drained and non-drained wounds. PATIENTS AND METHODS: Seventy consecutive patients undergoing CEA and 73 patients who underwent 106 groins dissection were separately and blindly randomised into two groups: group (a) with wound drain and group (b) without wound drain. A duplex scan was carried out post-operatively to document the presence and volume of any wound haematoma. RESULTS: The majority of wounds did not show any evidence of collections. 1. In the CEA patients duplex scan revealed wound haematoma in 8 patients with a median volume of 25 ml (5-65) in group (a) in comparison to 7 wound haematomas 31 ml (3-72) in group (b). Median suction drain drainage was 42 ml (10-120) when used. There was no significant difference between the two groups. Three patients 4.3% (two from the drain group) underwent evacuation of haematoma post-operatively.2. In the groin dissection patients most of the documented collections were trivial. Ultrasound scans showed 21 collections (20%), of these 7 (34%) were in group (a) and 14 (66%) were in group (b). There was no significant difference in wound collections between the two groups (p = 0.28). Only 5 collections (75%) exceeded 10 ml, three of them were in the drain group. One patient (1%), who did not have a drain, developed a wound collection, which needed re-exploration. When a drain was used the median drainage was 64.5 ml (range 10-220). CONCLUSION: These results based on accurate measurement of wound collection suggest that there is no benefit in terms of reduction of the volume of haematoma on wound drainage after CEA or arterial reconstruction surgery involving the groin. A selective policy of use of drainage is therefore recommended.

Aged↗
PubMed2004

The relationship between plasma MMP-1, -7, -8 and -13 levels and embolic potential during carotid endoluminal intervention.

BACKGROUND: Patients undergoing carotid endoluminal intervention are at risk of embolic stroke even with the use of distal protection devices. Matrix metalloproteinases (MMPs) have been implicated as a causal factor in plaque instability leading to spontaneous embolisation. We investigated whether plasma MMP levels correlated with the embolisation during carotid endoluminal intervention. METHODS: Thirty circumferentially intact carotid endarterectomy specimens were subjected to a standardised angioplasty procedure in a pulsatile ex vivo model. Emboli collected in a series of distal filters were counted and sized. Plasma samples were collected pre-operatively and analysed for MMP-7 and MMP-8 levels using Western immunoblotting. MMP-1 and MMP-13 levels were determined using ELISA. Emboli number and maximum size were correlated with plasma levels of the MMPs using Spearmans rank. RESULTS: Total MMP-8 levels were related to maximum embolus size (r=0.442, p=0.005) but not emboli number (r=0.342, p=0.052). MMP-1, -7 and -13 were not correlated with either emboli number or with maximum embolus size. CONCLUSION: Pre-operative plasma MMP-8 levels are related to the size of emboli from plaques during carotid endovascular intervention. Further in vivo studies need to be performed to assess the importance of this finding. There is potential for development of plasma markers to identify those patients at greater risk of embolic stroke during carotid endoluminal intervention.

Aged↗
PubMed2003

Carotid angioplasty in a pulsatile flow model: factors affecting embolic potential.

OBJECTIVES: Carotid endoluminal intervention is an alternative to surgery but carries a risk of embolic stroke even with distal protection devices. We investigated the clinical features and degree of stenosis related to number and size of emboli during carotid angioplasty. DESIGN: An experimental ex vivo study. MATERIALS: An ex vivo pulsatile flow model was used in which temperature, velocity, flow, pressure and viscosity characteristics were designed to simulate the carotid circulation. METHODS: Carotid endarterectomy specimens excised as intact cylinders (n = 28) were subjected to a standardised angioplasty procedure using radiological guidance. Emboli collected in filters placed distally were counted and sized using microscopy. RESULTS: Median number of emboli during angioplasty was 133 (range 15-1331). Median size of the largest embolus was 700 microns (range 75-2400). Severity of stenosis correlated with increased maximum size (r = 0.55, p = 0.012). Statin therapy >4 weeks pre-operatively was associated with reduced emboli number and size (54 (range 15-748) vs 247 (range 37-1331) [p = 0.023] and 400 microm (range 75-2400) vs 1300 microm (range 600-2200) [p = 0.022]). CONCLUSIONS: In this model a wide range of emboli number and size were produced. Number and size of embolic particles were highest in patients with high-grade stenoses not receiving statin therapy.

Aged↗
PubMed2000

Reduction in the response to coronary and iliac artery injury with photodynamic therapy using 5-aminolaevulinic acid.

OBJECTIVE: Photodynamic therapy (PDT) uses red light (non-thermal, non-ionising) to activate a previously administered photosensitizing drug. This inhibits neointimal hyperplasia in injured arteries in small animals where it appears safe and well tolerated. Our aim was to develop a method for percutaneous application of PDT to iliac and coronary arteries in a large animal model and investigate its influence on the remodeling and intimal hyperplastic response to balloon injury. METHODS: Studies were undertaken on 13 juvenile Large White-Landrace crossbred pigs (15-20 kg). After intravenous administration of the photosensitizing agent 5-amino laevulinic acid (ALA), the arterial tree was accessed via the left common carotid artery and balloon injuries made by over-distension in both common iliacs (thirteen animals) and one or two main coronary arteries (eight animals). Half the injured sites were then illuminated with red laser light transmitted via the catheter. Animals were culled 28 days later and tissue harvested for histomorphometry. RESULTS: Compared with control injured vessels, PDT treated, balloon injured coronary arteries had a larger lumen (1.4 vs. 0.8 mm2, P = 0.002), larger area within the external elastic lamina (2.8 vs. 2.2 mm2, P = 0.006) and smaller area of neointimal hyperplasia (0.4 vs. 0.7 mm2, P = 0.06), 28 days after intervention. Less neointimal hyperplasia and the absence of negative remodeling resulted in the lumen of PDT-treated, injured segments being the same as that of adjacent reference segments (1.5 vs. 1.6 mm2). Similar trends, but with smaller differences, were seen in the iliac vessels. CONCLUSIONS: Intra-arterial, trans-catheter PDT favourably influences the arterial response to balloon injury in both the coronary and peripheral circulations. This technique offers a promising new approach to restenosis after endovascular procedures.

Aminolevulinic Acid↗
PubMed1999

Clinical study of adjuvant photodynamic therapy to reduce restenosis following femoral angioplasty.

BACKGROUND: Photodynamic therapy (PDT) reduces neointimal hyperplasia and negative remodelling following balloon injury in small and large animal models. This clinical study investigated the role of adjuvant PDT following femoral percutaneous transluminal angioplasty (PTA). METHODS: Eight PTAs in seven patients (two women) with a median age of 70 (range 59-86) years were performed with adjuvant PDT. All patients had previously undergone conventional angioplasty at the same site which resulted in symptomatic restenosis or occlusion between 2 and 6 months. Each was sensitized with oral 5-aminolaevulinic acid 60 mg/kg, 5-7 h before the procedure. Following a second femoral angioplasty, up to 50 J/cm2 red light (635 nm) was delivered to the angioplasty site via a laser fibre within the angioplasty balloon. Patients were kept in subdued light overnight and discharged the following day. Outcome was assessed by duplex imaging at 24 h, 1, 3 and 6 months and by intravenous digital subtraction angiography at 6 months. A peak systolic velocity ratio (PSVR) of more than 2.0 at the angioplasty site was taken to represent restenosis. RESULTS: All patients tolerated the procedure well without adverse complications or death. All were rendered asymptomatic which was sustained throughout the study interval. All vessels remained patent and no lesion attained the duplex definition of restenosis. Median (interquartile range) PSVR across stenotic segments was 4.7 (3.7-5.7) before angioplasty, 1.1 (0.9-1.3) at 24 h and 1.4 (1.0-1.8) at 6 months after intervention (P = 0.04 compared with preoperative value). CONCLUSION: This pilot study suggests that endovascular PDT is safe and may reduce restenosis follow- ing angioplasty. The data justify a randomized controlled trial.

Aged↗
PubMed1998

Intra-arterial photodynamic therapy using 5-ALA in a swine model.

OBJECTIVES: To test the hypothesis that intravascular light could be delivered via a balloon catheter for arterial photodynamic therapy (PDT). DESIGN: Pig non-injury model. MATERIALS: Clinical catheter equipment. METHODS: Large White pigs (15-20 micrograms) were photosensitised with 5-aminolaevulinic acid (5-ALA) induced protoporphyrin IX (PpIX) at a concentration of 120 mg/kg. Arterial biopsies were taken at intervals between 30 mins and 24 h and frozen sections analysed using a CCD camera to give a temporal profile of fluorescence in each arterial layer. PDT was given to normal arterial segments via a 4 mm transparent PTA balloon inflated so as to occlude flow, but not distend the artery. Animals were culled at 3 and 14 days and the above segments harvested. RESULTS: Fluorescence peaked in the adventitia, intima and medial layers at 1.5, 4 and 6 h respectively. PDT at all time points produced VSMC depletion compared with controls. The degree of depletion mirrored the fluorescence profile of PpIX. CONCLUSIONS: PDT can be delivered via a standard PTA balloon with a transparent channel. This depletes the VSMC population within the arterial wall without complications. Intra-arterial PDT is therefore a potential therapy to reduce the incidence of restenosis post-angioplasty.

Aminolevulinic Acid↗
PubMed1998

Duplex scanning and effect of multisegmental arterial disease on its accuracy in lower limb arteries.

AIM: To assess the accuracy of duplex in assessment of peripheral arterial disease and determine the effect of multisegmental disease on the accuracy duplex as opposed to single lesion. PATIENTS AND METHODS: One hundred and seventy-seven lower limbs were examined in 90 patients who presented with lower limb arterial disease, (59 male, 31 female, median age 68 years--81 with intermittent claudication, eight rest pain, one ulceration). Patients were examined with duplex US, and arteriography (IA DSA). Two radiologists and two technologists were involved in this double-blind study. Patients were classified into five groups; groups with single stenotic lesions, single occlusions, multiple stenotic lesions or occlusions, and multiple mixed disease. Duplex accuracy was determined in each group. RESULTS: Duplex was able to differentiate between normal and disease arterial segment with a sensitivity of 92%, specificity 99%, PPV 91%, and NPV 100% and Kappa 0.87. Sixty-six limbs were found to have single lesions, and 68 multisegmental disease. Duplex showed accuracy with a sensitivity of 87%, and specificity of 99%, for single stenotic lesion and 95%, 96% respectively for multisegmental. For single occlusions duplex accuracy showed sensitivity 92% and specificity 100%, and for multisegmental occlusions, sensitivity 97%, and specificity 99%. For mixed multisegmental pathology (stenosis and occlusion), sensitivity 94% and specificity 97%. CONCLUSION: Duplex is an accurate tool in diagnosis of lower limb arterial disease and multisegmental pathology does not adversely effect this accuracy.

Aged↗
PubMed1997

Patch angioplasty following carotid endarterectomy using the ipsilateral superior thyroid artery.

OBJECTIVES AND DESIGN: Synthetic and saphenous vein patches, when used in the carotid territory, are disadvantaged by complications. We tested the feasibility of using a locally harvested artery, the ipsilateral superior thyroid artery (STA), as a source of patching material following carotid endarterectomy (CEA). MATERIALS AND METHODS: Twenty-two consecutive patients (15 male) with a median age of 70 (range 53-82) years underwent CEA with an intention to use the STA for patch angioplasty. The STA was harvested via a standard carotid incision and opened longitudinally to fashion a patch. RESULTS: Of the 22 STAs harvested, only two were rejected due to small calibre. Mean harvesting time was 12 min and there were no immediate complications. Duplex scanning has not revealed restenosis (mean peak velocity = 0.78 [range 0.45-1.16] m/s) in any patient with a median follow-up of 13 (range 3-19) months. CONCLUSIONS: This technique is quick, convenient and obviates many of the disadvantages associated with conventional patches. Follow-up has shown the technique to be both efficacious and durable in the medium term.

Aged↗
PubMed1997

Subpectoral breast reconstruction using the biodimensional system.

Increasing awareness among the general public has fuelled a demand for post-mastectomy breast reconstruction. However, owing to the limited number of plastic surgical centres this need is unlikely to be fulfilled in the near future. We report our early experience with a modified technique using a new subpectoral implant--the Biodimensional System. Seventeen consecutive patients underwent reconstruction (16 immediately) after mastectomy. In the group of patients having immediate reconstruction, the surgery was undertaken by the breast surgeon performing the primary procedure. This study demonstrates that an acceptable result can be obtained in the majority of patients and that it is possible for a breast surgeon to undertake primary reconstruction on selected patients using the Biodimensional System. It is hoped that this may aid patients in their physical and mental rehabilitation.

Breast Implants↗
PubMed1996

The management of retroperitoneal soft tissue sarcomas.

Over a 5-year period, all retroperitoneal soft tissue sarcomas (119) referred to the Royal Marsden Hospital, London, U.K., were recorded prospectively on a database and managed with a consistent treatment policy. On multivariate analysis, the significant factors responsible for determining prognosis were grade and completeness of excision. Despite improvements in surgical clearance rates (nearly 50% completely excised in this series), the prognosis was poor with 2- and 5-year survival rates of 53 and 20%, respectively. Further improvements in survival rates will depend on better adjuvant treatment.

Adolescent↗
PubMed1996

Hindquarter amputation for lymphangiomatosis.

We describe the presentation of a 16-year-old boy with locally advanced lymphangiomatosis affecting the left thigh and groin. This is a difficult disease to both diagnose and treat, and one in which radical surgery may be necessary to effect a cure or even palliation. In this case, hindquarter amputation allowed a previously wheelchair-bound teenager to mobilize unaided.

Adolescent↗
PubMedDate not supplied

Critical limb ischemia in the dialysis-dependent patient: infrainguinal vein bypass is justified.

The combination of critical limb ischemia and end-stage renal failure (ESRF, ie, dialysis- dependent) represents severe systemic atherosclerosis and is associated with a very poor medium-term survival. Many nephrologists and surgeons advocate primary amputation. We examined the recent experience in this unit to determine whether infrainguinal bypass in these patients can be justified. Retrospective study of all patients with critical limb ischemia and ESRF undergoing surgery in a regional vascular and renal unit between January 1996 and May 2003. Forty-two patients with ESRF (median age 65 years) were referred with critical limb ischemia. Seventeen patients underwent 24 (7 bilateral) infrainguinal bypasses (17 autologous vein, 7 polytetrafluoroethylene [PTFE] conduit; tissue loss in 21/24, 88%), and 25 patients had primary major amputations of 32 limbs. Early occlusion occurred in 5 grafts (21%, all 5/5 PTFE). In-hospital mortality was 13% in the bypass group, 24% in the amputation group. Median in-hospital stay was 59 days in the bypass group, 46 days in the amputation group. Thirty-day, 1- and 2-year survival was 88%, 50%, and 33% in the bypass group; 83%, 39%, and 35% in the amputation group. The limb salvage rate was 66% at 1 year. Seventy-five percent (18/24) of operated on limbs (15/17 of vein grafts) avoided major amputation at follow-up (median 18 months) or death. The combination of critical limb ischemia and end- stage renal failure carries a poor medium-term survival independent of primary amputation or surgical revascularization. Infrainguinal bypass in selected cases with vein conduit can, however, allow the majority of these patients to avoid major limb amputation.

Adult↗