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J R Allenberg

Publications and source records attributed to J R Allenberg.

At least 55 records · Page 3Linked to original sources

[Bilateral tibial compartment syndrome with crush symptoms after cannabis abuse].

Acute compartmental syndrome (CS) is a surgical emergency. Different conditions in which high non-physiological pressure appears within a closed fascial space reduce the necessary blood perfusion. CS is caused by trauma, burns, bleeding in patients with coagulopathies arterial injuries, nephrotic syndrome or unusual physical exercise with secondary compartmental swelling. When decompression occurs too late, permanent loss of function and limb contracture may result. In the following paper we report on a case of four-compartmental syndrome in the lower legs of a patient with drug intoxication. After cannabis consumption, the patient fell asleep sitting cross-legged. During our first examination several hours later, the signs of compartmental syndrome with spontaneous pain, turgid swelling and paresis were present. Bilateral skin incision technique was used to gain entrance into the four compartments in both lower legs. Immediately after the operation, the patient showed crush syndrome with high serum creatine kinase activity 140.501 U/l and acute renal failure caused by rhabdomyolysis. Within 2 weeks of haemofiltration and dialysis, a full recovery to a normal serum creatinine level of 0.7 mg/dl was achieved. After emergency treatment and rehabilitation, the patient showed neither vascular nor neural defects.

Adult↗

[Widening mediastinum after blunt thoracic trauma: an unexpected differential diagnosis].

We report our experience concerning a young, white, healthy woman who had a typical blunt chest injury caused by a severe car accident. We had to evaluate and differentiate the initial roentgenographic post-traumatic mediastinal enlargement in order definitely to exclude a suspected covered rupture of the thoracic aorta or the heart caused by this high-velocity deceleration trauma. The difficulties encountered are critically discussed with regard to the unexpected primary thymoma that was diagnosed postoperatively. The diagnostic algorithm in blunt chest injury is also discussed. The controversy about the classification and management options of primary thymic tumors is also presented.

Adult↗

[Classification of hemodynamic changes in renal artery stenosis using cine magnetic resonance phase contrast flow measurements].

PURPOSE: To evaluate the use of high-temporal resolution cine MR phase-contrast flow measurements for assessment of flow dynamics in renal artery stenosis (RAS). MATERIAL AND METHODS: In a dog model, cine MR flow measurements were validated by comparing the MR flow data to an invasive transit-time ultrasound reference technique for different degrees of RAS. Cardiac-gated MR flow curves were recorded in 56 renal arteries of 28 patients with a temporal resolution of at least 32 ms. In all cases RAS was confirmed by digital subtraction angiography (DSA). Abnormalities of flow dynamics were assessed in the calculated flow curves using the MR parameters mean flow, maximum velocity, and time to systolic maximum. RESULTS: By means of the MR blood flow parameters high-grade stenoses (> 50%, n = 23) were detected with sensitivity of 100% and specificity of 94% with reference to DSA. The overall differentiation between stenoses (n = 37) and non-stenosed vessels (n = 19) revealed a sensitivity of 87% and a specificity of 100%. CONCLUSION: Analysis of cardiac-gated MR flow curves provides a non-invasive method to assess the hemodynamic significance of RAS and thus allows a functional evaluation in relation to the morphologic characteristics of the stenosis.

Adolescent↗

Degree of carotid artery stenosis. Comparison of selective and non-selective angiographic findings with surgical specimens.

OBJECTIVE: To compare the degree of vessel narrowing seen on selective and non-selective carotid artery catheter angiograms using criteria set by NASCET and ECST with the results obtained from corresponding surgical specimens. SUBJECTS: In 40 preoperative angiograms (20 non-selective, 20 selective) the 'distal' degree of internal carotid artery (ICA) stenosis according to NASCET criteria and the 'local' degree of stenosis according to ECST criteria was assessed. These data were compared with the 'distal' and 'local' degree of ICA stenosis obtained by measuring the specimens and the diameter of the distal ICA intraoperatively. RESULTS: The median 'local' degree of stenosis was 86.5% in the specimen and 83.5% in the selective angiograms (difference not significant). In non-selective angiography the median 'local' degree of stenosis was 77.5% compared to 84% in the corresponding specimens (P < 0.01). The median 'distal' degree of stenosis in selective angiography was 76.5 versus 75.5% in the specimens (n.s.). The median 'distal' degree of non-selective angiography was 67% compared to 77.5% in the corresponding specimens (P = 0.02). The trend to underestimate high grade stenosis (above 90%) was more pronounced in non-selective than in selective angiography. Medium grade stenosis (60-80%) was slightly overestimated in selective angiography. CONCLUSION: Selective angiography is more accurate in determining the 'true' degree of stenosis in internal carotid artery disease, taking into account a slight overestimation of medium grade stenosis. High grade stenosis is underestimated in both selective and non-selective angiography. These observations extend to both the ECST and NASCET criteria of measuring the degree of stenosis, which differ by about 10%.

Aged↗

Morphometry and classification in abdominal aortic aneurysms: patient selection for endovascular and open surgery.

PURPOSE: To evaluate the anatomic morphology of abdominal aortic aneurysms (AAAs) and compose a classification system to facilitate patient selection for endovascular graft (EVG) repair. METHODS: Data on 242 consecutive AAA patients evaluated on a nonemergent basis in a 3.5-year period to July 1996 were prospectively entered into a registry. Patients were examined using sequential intravenous spiral computed tomographic angiography and intraarterial digital subtraction angiography. The data collected and analyzed included: diameters of the supra- and infrarenal aorta, aneurysm, aortoiliac bifurcation, and iliac arteries; lengths of the proximal neck, distal cuff, and aneurysm; degrees of iliac artery tortuosity; and occlusion of the visceral, renal, or iliac arteries. RESULTS: The 242 aneurysms could be easily grouped into three distinctive categories related to the extent of the aneurysmal disease. Type I AAAs (11.2%) had nondilated, thrombus-free infrarenal (15 mm) necks and distal (10 mm) cuffs appropriate for EVG anchoring. In type II and its subgroups (72.3%), a sufficient proximal neck was present, but the aneurysm extended into the iliac arteries; 56% of these were eligible for a bifurcated endograft. In type III (16.5%), a sufficient proximal neck was missing, independent of distal involvement. In all, 51.7% were good EVG candidates based on AAA morphology. Taking into consideration relevant concomitant vascular diseases, proximal iliac kinking, and iliac, renal, or visceral occlusive disease, only 30.2% of the population were potential candidates for an efficient and secure EVG repair using the devices currently available. CONCLUSIONS: In contrast to classical open repair, detailed preoperative measurements are recommended for EVG planning. The use of liberal EVG indications may lead to a higher incidence of complications, whereas restrictive morphology-based selection criteria may offer excellent results.

Aged↗

Entrapment of the popliteal artery and its surgical management in a 20-year period.

BACKGROUND: This study was a retrospective review of 19 patients with popliteal artery entrapment syndrome (PAES) treated in a 20-year interval. METHODS: The Heidelberg classification of PAES was used, which differentiates three categories of entrapment: in type I the popliteal artery has an atypical course, in type II the muscular insertion is atypical, and in type III both conditions are present. Besides decompression of the popliteal artery the commonest operative reconstruction used was resection of the atherosclerotic part of the artery and autologous vein interposition grafting (n = 12). Local thromboendarterectomy was done in seven cases, six with a vein patch angioplasty repair. RESULTS: Follow-up ranged from 6 months to 20 years (mean 9.5 years). There was no limb loss. The rate of complications was lowest after primary venous interposition (two of 12) compared with five of 11 when venous interposition was not used (P < 0.01). CONCLUSION: Autologous saphenous vein interposition grafting seems to be the best treatment for PAES.

Adult↗

[Detection of the hemodynamic effects of renal artery stenosis with MRI flow measurement].

Data derived from the MR-CINE phase-contrast flow measurement of renal arteries correlates well with the angiographically detected degree of stenosis and scintigraphic measurements. MR data permit the quantitative analysis of altered hemodynamics and MR is a non-invasive substitute for angiography preoperatively and during follow-up. Angiography is indicated only for the evaluation of morphological criteria.

Adolescent↗

[Carotid endarterectomy in the early phase after a non-disabling stroke: 1980-1995 results].

In 56 patients, carotid endarterectomy (CEA) was performed 14 days (median) after a non-disabling carotid-related stroke with a perioperative minor stroke rate of 3.6%. Even large ischemic brain infarcts on CT scan did not exclude patients from CEA, as long as the patient had reached a neurologic plateau. The data from this study indicate that CEA can be performed safely in properly selected patients, and might reduce the high risk of a recurrent stroke (5%-9.5% within 30 days).

Adult↗

Pedal bypass for limb-threatening ischaemia: an 11-year review.

Fifty-six patients with limb-threatening ischaemia had pedal revascularization with either autologous vein (n = 39) or sequential composite graft with a 6-mm polytetrafluoroethylene prosthesis and autologous vein (n = 17); 75 per cent had gangrene and skin necrosis and 25 per cent had ischaemic rest pain alone. Twelve grafts occluded within the first week, and resulted in major amputation in eight patients after unsuccessful revision. Two patients required amputation for persistent ischaemia despite a patent bypass. One patient died from bowel perforation (2 per cent). In 47 (84 per cent) of the 56 patients limb and life were preserved. The primary patency rate after 1, 2 and 4 years was 65, 55 and 55 per cent respectively, the secondary patency rate was 71, 62 and 62 per cent, and cumulative limb salvage rates were 77, 71 and 66 per cent. Life-table survival rates during follow-up (median 25 (range 0-112) months) were 89, 78 and 52 per cent respectively after 1, 2 and 4 years. Thirteen of 21 patients who died during follow-up did not require major amputation. Pedal reconstruction with autologous vein provides limb salvage until death in nearly two-thirds of patients with critical limb ischaemia resulting from crural arterial occlusive disease.

Adult↗

[The accuracy of angiography and CT angiography of the carotid bifurcation compared to macro-morphological correlation].

PURPOSE: To compare the degree of carotid artery stenosis in angiography and CT angiography with the degree of stenosis measured in an intact eversion endarterectomy specimen. METHODS: Preoperative angiograms (intraarterial DSA, 512 x 512 matrix) and CT-angiograms (24 sec spiral scan, slice thickness 2 mm, pitch 1.5) were taken in 12 patients with symptomatic carotid stenosis. Evaluation of the degree of stenosis was performed according to the NASCET ("distal" degree) and ECST ("local" degree) methods. These data were compared with measurements of the surgical specimens. RESULTS: The median "local" degree of stenosis in angiograms was 81.5% (range: 70-99%), in CT angiograms 83% (59-94%) and in specimens 85.5% (65-96%). The "distal" degree of stenosis was 79% (50-99%) in angiograms, 85.5% (55-99%) in CT angiograms and 81% (52-95%) in specimens. CT angiography slightly overestimated the degree of stenosis compared with the specimen, whereas angiography slightly underestimated the true degree of stenosis. However, these differences were not statistically significant. CONCLUSION: CT angiography is able to predict the degree of internal carotid stenosis when compared with an intact surgical specimen. It is as accurate as the "gold standard" of invasive angiography.

Angiography, Digital Subtraction↗

[Infrarenal abdominal aortic aneurysm: morphological classification as decision aid for therapeutic procedures].

This clinical trial aimed to prospectively investigate the morphological structure of infrarenal abdominal aortic aneurysms (AAA) to establish a valid dataset in the preoperative assessment supporting either the conventional or endovascular (TPEG) surgical approach. Regarding both the general feasibility testing and safe TPEG placing, all the anatomic AAA data must already be measured preprocedurally, due to the necessity for conversion as a frequent consequence of an intraprocedural failure. Between January 1993 and June 1995, all the patients (n = 159) admitted for elective AAA repair, were prospectively analysed. Graded on the basis of these measurements we developed a new AAA classification system supporting the kind of the surgical procedure (standard) approach vs. TPEG). Three different types of AAA were clearly defined. Due to morphological AAA criteria, 86 out of 159 patients (54.1%) might be suitable for TPEG (Type I, IIA and IIB). An infrarenal (proximal) neck < 15 mm, an infrarenal aortic diameter > 24 mm or an extension of the aneurysm to the iliac bifurcation are considered to be exclusion criteria for TPEG placement. In consideration of relevant co-morbidities (e.g. renal artery stenosis, SMA occlusion, iliac occlusive disease, simultaneous operations) only 43 out 159 patients (27.1%) were good candidates for TPEG. In general, smaller AAA are more appropriate for TPEG repair due to better proximal and distal fixation. As a consequence, indication criteria for AAA repair must not be expanded to smaller AAA.

Aged↗

[Prospective preoperative morphometry of abdominal aortic aneurysms: selective patient management for endovascular surgery].

The objective of this prospective clinical investigation of 205 elective abdominal aortic aneurysm (AAA) patients over a 3-year period. 1993-1995, was both to evaluate the morphology and aortic dimensions of AAA as a management decision for patient selection for endovascular grafting and to correctly plan the custom-made TPEG size and shape prior to the procedure.

Aged↗

[Carotid TEA and perioperative thrombolysis: a new concept in therapy of acute ischemic stroke].

In seven carotid-related acute hemispheric strokes with simultaneous embolic occlusion of the middle cerebral artery thrombolysis with urocinase or rt-PA was performed preoperatively (n = 3) or intraoperatively (n = 4) after carotid endarterectomy. Four patients recovered totally, three patients showed a remarkable improvement and were able to walk postoperatively. The combination of carotid endarterectomy and thrombolysis (simultaneous or staged) is a new option in the emergency treatment of an acute carotid-related stroke and should be evaluated in prospective interdisciplinary studies.

Adult↗

[Endovascular reconstruction of infrarenal abdominal aortic aneurysm].

Animal experiments in the 80's demonstrated the feasibility of the concept first inaugurated by Dotter in 1969 of the endovascular implantation of a stent-graft prosthesis for the treatment of abdominal aortic aneurysm. In September 1990 Parodi was the first to treat a patient with an AAA using the implantation of a TPEG (transluminal placed endovascular stented graft). The rapid development of a variety of different devices can be observed since resulting in about 400 such prosthesis being implanted world wide for the treatment of AAA. The experience accumulated so far shows that severe complications can be avoided if morphology-based criteria are considered for the various treatment options (AAA classification type I, type IIa-c, type III). Despite considerable lethal incidents, technical mishaps and severe complications to date, the potential of TPEG for a structured approach to the treatment of AAA has to be evaluated. Prerequisites are 1) a competent team based on a close mutual cooperation of vascular surgeons and interventional radiologists, 2) a careful selection of patients, 3) TPEG to be performed in especially equipped operation theatres permitting the immediate application of conventional surgery if necessary, and 4) the implantation to be performed as a clinical study with flawless documentation of the procedure and follow-up.

Angioplasty, Balloon↗

[Endovascular and open reconstructive surgery of renal artery lesions].

Besides antihypertensive drug treatment and reconstructive surgery, the percutaneous transluminal angioplasty became an established treatment modality for renal artery stenosis since the late 70's. The treatment aimed at curing the renovascular hypertension, at normalizing and improving of both compensated and decompensated renal insufficiency in order to avoid prolonged hemodialysis after acute renal failure. Endovascular procedures contributed significantly to reach a normotensive state, particularly in cases with renal artery stenosis concomitant with fibromuscular dysplasia and gives similar results as open surgical methods if certain morphological features are considered. However, surgery is generally more effective than endoluminal treatment when all forms of renal artery stenosis are considered together. This holds true in particular for ostial stenosis, complete obstruction of the renal artery, aneurysms and a multitude of rare renovascular diseases. Surgery should be first line treatment to preserve or improve the renal function. According to the pertinent literature, endovascular methods should be considered first for the treatment of renovascular hypertension. Despite the frequent repetition of potential advantages of PTA, a first direct comparison of both modalities demonstrated better primary results after surgical treatment. Even the total cost were similar since PTA requires frequent follow-up with short intervals necessitating secondary interventions.

Angiography↗

[Determination of the degree of stenosis of the internal carotid artery in the surgical specimen after eversion TEA: comparison with angiography and c-w-Doppler ultrasound].

UNLABELLED: 22 carotid specimens following eversion-endarterectomy were compared with preoperative assessment of carotid stenosis obtained angiographically and by c-w-Doppler-sonography. The intact, unsplit specimens were perfused with a liquid plastic material (Palavit M). After hardening of the plastic material the specimens were removed. The local degree of carotid stenosis with respect to diameter reduction was assessed by direct measurement of the plastic specimens at the narrowest site compared with the diameter of the carotid eversion specimens at the place of the maximum stenosis. The distal degree of carotid stenosis was assessed by comparison of the diameter of the distal internal carotid artery obtained intraoperatively with the measurements of the plastic specimens (1 mm vascular wall thickness of distal internal carotid artery was taken into account). RESULTS: Both the local and the distal degree of carotid stenosis diameter (mean 84.7% +/- 8.4% and 82.1% +/- 9.1% respectively) were underestimated in the preoperative angiogram (79.8 +/- 9% by ECST-criteria and 69 +/- 10.3% by NASCET-criteria) in most of the cases. The difference of the diameter reduction was statistically significant (p < 0.05 and p < 0.01 respectively, Wilcoxon signed rank test). The c-w-Doppler assessments were 82.6 +/- 8.2% (n.s.). CONCLUSION: Our results suggest that the preoperative assessment of internal carotid stenosis obtained angiographically or by c-w-Doppler-sonography easily underestimate the true degree of carotid stenosis.

Adult↗