Iatrogenic vertebrojugular arteriovenous fistula

Arteriovenous fistulae originating from the vertebral artery are rare. We report a patient in whom a vertebral artery-jugular venous fistula developed following insertion of a central venous catheter via the internal jugular vein. The fistula was successfully occluded surgically.

[Technical modification of the rheolytic thrombectomy]

A 48-year-old male patient with acute occlusion (5 cm) of a leg artery was treated with the rheolytic thrombectomy (RT). As recommended the catheter is applied via a single coaxial running guide wire, which is removed later. If an additional wire has been placed in the occluded vessel segment, the occlusion can be passed repeatedly. A 30 degrees bent catheter tip improves the removal of wall-adherent thrombotic material. The occluded segment was successfully recanalized with the RTC, 270 ml of heparinised saline had been injected. The blood examinations showed mild haemolysis.

[The initial results of percutaneous therapy of popliteal aneurysms with stents]

PURPOSE

Are percutaneous stents a therapeutic alternative to bypass surgery in the treatment of popliteal aneurysms?

MATERIAL AND METHODS

Three patients with femoropopliteal occlusion related to popliteal aneurysms were treated percutaneously. In two cases coated stents were used. In the third patient who underwent prior bypass surgery due to local fibrinolysis a reperfusion of the aneurysm occurred. He was treated with a Wallstent.

RESULTS

Primary stent treatment was successful in all cases. There were no complications. One patient was lost to follow-up. One of the two coated stents occluded after one month due to a poor run-off of only one lower limb artery. The other coated stent is still patent after 6 months proven by angiography.

CONCLUSION

Percutaneous therapy with coated stents could be an alternative to surgical bypass therapy for popliteal aneurysms. Obviously long-time patency is related to sufficient run-off.

[MR angiography in fibromuscular dysplasia of the cervical arteries]

PURPOSE

To determine 3-D time of flight MR angiography for evaluation of fibromuscular dysplasia in cervical vessels.

MATERIAL AND METHODS

In 386 selective angiograms of cervical vessels fibromuscular dysplasia was revealed in 4 female patients in the age of 30-54 years. FMD was located in the carotid artery (n = 5) and in the vertebral artery (n = 2) with a total of 8 lesions.

RESULTS

6/8 of the lesions of the seven cervical vessels were located typically in the mid cervical portion of the vessels and 2/6 lesions were located in the atlas loop of the vertebral artery. 4 lesions showed moderate stenosis and 4 vessels showed only mild stenosis. These patterns which demonstrated the typical morphology of fibromuscular dysplasia with alternating irregular zones of widening and narrowing were evaluated well with MR angiography, the others were missed.

CONCLUSION

MR angiography is suitable for detection of fibromuscular dysplasia when the characteristic pattern is combined with moderate stenosis of the vessel. Conventional angiography remains the standard of reference.

Mucosal tolerance to experimental autoimmune myasthenia gravis is associated with down-regulation of AChR-specific IFN-gamma-expressing Th1-like cells and up-regulation of TGF-beta mRNA in mononuclear cells

Oral and nasal administration of nicotinic acetylcholine receptor (AChR) to Lewis rats prior to myasthenogenic immunization with AChR and complete Freund's adjuvant (CFA) resulted in prevention or marked decrease of the severity of experimental autoimmune myasthenia gravis (EAMG) and suppression of AChR-specific B-cell responses and of AChR-reactive T-cell function. To examine the involvement of immunoregulatory cytokines and the underlying mechanisms involved in tolerance induction, in situ hybridization with radiolabeled cDNA oligonucleotide proves was adopted to enumerate mononuclear cells (MNC) expressing mRNA for the proinflammatory cytokine interferon-gamma (IFN-gamma), the B cell-stimulating interleukin-4 (IL-4), and the immunosuppressive transforming growth factor-beta (TGF-beta). Popliteal and inguinal lymph nodes from EAMG rats contained elevated numbers of AChR-reactive IFN-gamma, IL-4, and TGF-beta mRNA-expressing cells, compared to control rats receiving PBS orally or nasally and injected with CFA only. Oral and nasal tolerance was accompanied by decreased numbers of AChR-reactive IFN-gamma and IL-4 mRNA-expressing cells and strong up-regulation of TGF-beta mRNA-positive cells in lymphoid organs when compared to nontolerized EAMG control rats. The results suggest that IFN-gamma and IL-4 are central effector molecules in the development of EAMG and that TGF-beta plays an important role in tolerance induction to EAMG.

Effect of intraarticular pressure on patellar position. Computed tomography study in cadaveric specimens

RATIONALE AND OBJECTIVES

The purpose of the study was to evaluate the effect of articular fluid distention on patellar position at different degrees of knee angulation.

METHODS

Patellar position in 10 cadaveric knee specimens was determined with 30, 100, and 200 mm Hg joint distention at 45, 20, and 5 degrees of knee flexion using computed tomography. Patellar tilting and lateromedial and anteroposterior displacement of the patellar position were analyzed.

RESULTS

Lateral tilting increased with greater articular distention and decreasing knee flexion. At 5 degrees of flexion and 200 mm Hg of distention, change in lateral tilting ranged from -7 to +5 degrees. At 45 degrees of flexion and increased distention, the patellar shift ranged from 6 mm medialization to 1 mm lateralization for 200 mm Hg, but the patellar position was more variable at 5 degrees of flexion with increasing intraarticular pressure (range 7 mm medialization to 8 mm lateralization). With increasing articular pressure the patellae were increasingly displaced anteriorly with the most pressure-dependent changes at 45 and 20 degrees of knee flexion.

CONCLUSIONS

Fluid distentions of the knee joint have unpredictable and varying effects on the patellar position and vary considerably among persons. When judging patellar position during arthroscopy and in patients with large joint effusions, the arthroscopist and radiologist should be aware of these effects.

Augmented expression of tumour necrosis factor-alpha and lymphotoxin in mononuclear cells in multiple sclerosis and optic neuritis

The involvement of proinflammatory cytokines tumour necrosis factor-alpha (TNF-alpha) and lymphotoxin (LT) in multiple sclerosis is suggested by the parallel occurrence of these proinflammatory cytokines in acute and chronic active multiple sclerosis brain lesions. We describe the use of in situ hybridization with radiolabelled cDNA oligonucleotide probes to detect and enumerate TNF-alpha and LT mRNA expressing mononuclear cells without culture, and after culture in the presence of myelin basic protein (MBP), control antigens or without antigen. Compared with patients with aseptic meningo-encephalitis, non-inflammatory neurological diseases and healthy controls, the multiple sclerosis patients had elevated numbers of TNF-alpha and LT mRNA expressing mononuclear cells in blood when enumerated without previous culture, and also after culture with MBP. The MBP-induced upregulation of TNF-alpha and LT was major histocompatibility complex (MHC) class II molecule dependent. Tumour necrosis factor-alpha mRNA expressing mononuclear cells were further enriched in the multiple sclerosis patients' CSF. Positive correlations were observed in multiple sclerosis between TNF-alpha and LT mRNA expressing blood mononuclear cells, MBP-reactive TNF-alpha and LT mRNA expressing cells, and TNF-alpha and interferon-gamma (INF-gamma) mRNA expressing mononuclear cells. Upregulation of TNF-alpha correlated positively with exacerbation, enhanced disability and the secondary progressive phase of multiple sclerosis. Patients with optic neuritis, in many instances representing very early multiple sclerosis, had TNF-alpha and LT positive blood mononuclear cells that were elevated to the same extent as patients with clinically definite multiple sclerosis. The findings support the hypothesis that TNF-alpha and LT play a harmful role in the development of multiple sclerosis and suggest that TNF-alpha could be useful as a disease activity marker in multiple sclerosis.

Spiral CT angiography and selective digital subtraction angiography of internal carotid artery stenosis

PURPOSE

To determine whether spiral CT angiography allows accurate, quantitative evaluation of anatomic abnormalities, including detection of additional lesions, delineation of plaque morphology, and estimation of degree of internal carotid artery stenosis.

METHODS

Spiral CT angiography with a maximum intensity projection technique was compared with selective digital subtraction angiography (DSA) in 92 carotid arteries. The category of stenosis was determined according to the North American Symptomatic Carotid Endarterectomy Trial: mild (0% to 29%), moderate (30% to 69%), severe (70% to 99%), and occlusion (100%).

RESULTS

In 78 (85%) of the 92 cases, spiral CT angiography and selective DSA demonstrated the same degree of stenosis. All occlusions (n = 19) were diagnosed correctly with spiral CT angiography. Spiral CT angiography agreed with selective DSA in the classification of stenosis in 59% of the group with mild stenosis, in 82% of the group with moderate stenosis, and in 90% of the group with severe stenosis. In the groups with mild (n = 13), moderate (n = 9), and severe (n = 27) stenosis, correlation of spiral CT angiography with selective DSA was significant. Calcified plaques were readily diagnosed with the use of spiral CT angiography but delineation of ulcers was poor. Tandem lesions were not visible owing to the limited coverage.

CONCLUSION

Spiral CT angiography is useful for the detection of proximal internal carotid stenoses that are greater than 30%. Depiction of mild stenoses appears to be limited. CT is superior for the detection of calcified plaques but it is not useful for the detection of ulcers.

[CT-guided punctures: diagnostic value, therapeutic consequences and economic aspects]

PURPOSE

To evaluate the diagnostic and clinical relevance and therapeutic consequences of CT-guided biopsy with regard to economic aspects.

METHODS

213 CT-guided biopsies in 190 patients were evaluated. All information regarding patient referral, reason for request, body region, underlying diagnosis, and clinical consequences were registered over a period of 22.2 +/- 9.4 month.

RESULTS

Patient referral to biopsy was mainly from the departments of surgery, internal medicine, and radiotherapy with the question of tumor and metastasis. Less than 5% of biopsies were performed in outpatients. Main regions were the lung (39%), the abdomen (35%), and the skeleton (11%). Biopsy and surgical histology corresponded in 73%. Largest diagnosis groups were benign unspecific tissues or other benign lesions in 24%. As a result of CTP no further procedures were necessary in 22.5%. Follow-up studies or conservative treatment were indicated in 11.3%. Surgical procedures were needed in only 15.5%. There was only one complication requiring therapy.

CONCLUSION

CT-guided biopsy is a safe procedure, which helps to avoid unneccessary cost-intensive diagnostics and surgical treatment. If CTP is performed early and in outpatients residence time in the hospital is reduced and thus money is saved.

[Spiral CT angiography versus DSA in detection of carotid stenoses]

PURPOSE

To determine the value of spiral CT angiography for evaluation of internal carotid artery stenosis.

METHODS

Spiral CT angiography was compared with selective intraarterial DSA in 40 patients with 72 internal carotid artery stenoses. Quantification of stenoses was performed according to the NASCET-study and categorized in mild (0-29%), moderate (30-69%), severe (70-99%) and occlusion (100%).

RESULTS

The total agreement of spiral CT angiography with DSA in all stenoses was 78% (r = 0.933; p < 0.0001). In the mild stenoses group there was an agreement of 56% (r = 0.598; p = 138), in the moderate stenosis group there was an agreement of 59% (0.623; p = 0.0128) and in the group with severe stenosis the agreement was 97% (0.944; p < 0.0001). All occlusions were correctly interpreted by spiral CT angiography (r = 1; p = 0.0082).

CONCLUSION

The agreement of spiral CT angiography with DSA is good. Especially SCTA allows a good correlation in the severe stenosis group and in the occlusion group. DSA remains the standard of reference, because of its ability to demonstrate tandem lesions and collateral flow.

Influence of different fasting periods on P-31-MR-spectroscopy of the liver in normals and patients with liver metastases

The purpose of this study was to determine the influence of different fasting periods on the in vivo P-31-MR spectroscopy of the healthy liver and patients with liver metastases. Image-guided localized P-31-MRS was performed in 24 patients with liver metastases and in 20 healthy volunteers. The spectra were obtained with a whole body scanner operating at 1.5 T using a surface coil. The P-31-MRS was performed after a fasting period of 3-5 h (group 1) and after overnight fasting (group 2). The PME/beta-NTP, PDE/beta-NTP and Pi/beta-NTP were calculated from P-31-MR spectra and were compared in relation to the nutrition status of the volunteers and patients. The PME/beta-NTP and PDE/beta-NTP were significantly increased in spectra of patients with metastases. There were no significant changes in the ratios of phosphorus metabolites in healthy liver tissue or in liver metastases after a fasting period of 3-5 h as compared with overnight fasting.

[A modified technic for local rt-PA catheter-mediated lysis]

PURPOSE

To develop an economic and efficient concept for more time-saving local rt-PA thrombolysis therapy.

METHOD

40 patients with peripheral vascular occlusive disease stage IIb-III according to the Fontaine classification and with angiographically proven occluded segments of pelvic and lower limb arteries were treated by a modified concept of local rt-PA catheter thrombolysis. Via a thin guide wire the catheter for thrombolysis is slowly advanced through the thrombus without fluoroscopic control, outside the room in which angiography is performed. In 24 cases a short-term lysis and in 16 cases a long-term lysis was carried out.

RESULTS

The initial success rate was 75%, the patency rate in six months' follow-up was 66.7%. The ankle-brachial index decreased from 0.4 +/- 0.3 to 0.8 +/- 0.2 on the average. There were no relevant clinical complications. The average occupancy time of the angiography room or table was 60 +/- 52 min, the average time of fluoroscopy was 17 +/- 13 min.

CONCLUSION

In modified local rt-PA thrombolysis, short-term lysis and long-term lysis were mostly performed outside the angiography room, so that the exposure to radiation and there fore the radiation dose were reduced for both the patient and the attending staff. The angiography room is thus available for other patients and can therefore be used more efficiently.

[Loss of brain stem auditory evoked potential waves I and II during controlled hypotension]

For surgical removal of a malignant choroid melanoma, it is necessary to reduce systolic blood pressure to around 50-60 mmHg in order to prevent choroidal haemorrhages. However, blood pressure reduction is associated with the risk of cerebral ischaemia. We report a patient with a malignant choroid melanoma in whom waves I and II of the brainstem auditory evoked potentials (BAEP) disappeared during surgery under controlled arterial hypotension and hypothermia (31.1 degrees C). The waves could be recorded again immediately after the mean arterial pressure was increased from 48 to 77 mmHg. The oesophageal temperature had dropped by 0.3 degrees C at this time. The 2-channel electroencephalogram (EEG) showed no irregularities during this time period. A bilateral, reversible, apparently blood-pressure-dependent loss of waves I and II during arterial hypotension despite a normal EEG has to our knowledge not been previously described in the literature. The isolated loss of waves I and II with maintenance of waves III, IV, and V is unusual. The literature contains reports of acoustic neurinoma patients in whom only wave V could be recorded. This is regarded as an indication of continued impulse conduction despite the loss of waves I to IV. Others have observed a patient with temporary and reversible loss of BAEP wave I due to vasospasm of the internal auditory artery that apparently occurred during or shortly after manipulation of the internal auditory meatus. Assuming anatomic peculiarities in the blood supply to the generators of the BAEP waves, a stenosis of the basilar artery could be considered as the cause of the bilateral reversible loss of waves I and II. Another potential source could be induced hypothermia, but this does not seem very likely because the patient's temperature was 0.3 degrees C lower at the return of the waves than at their loss.

Expression of IFN-gamma, IL-4, and TGF-beta in multiple sclerosis in relation to HLA-Dw2 phenotype and stage of disease

Multiple sclerosis (MS) is associated with upregulation of both proinflammatory (interferon-gamma, IFN-gamma) and immunosuppressive (transforming growth factor-beta, TGF-beta) cytokines. To examine a possible relation between the MS-related HLA haplotype Dw2 and cytokine profiles, we used in situ hybridization with labeled cDNA oligonucleotide probes to detect transcripts of the T helper type 1 (Th 1) cell related IFN-gamma, the Th2 cell related interleukin-4 (IL-4) and of TGF-beta in blood and cerebrospinal fluid (CSF) mononuclear cells from 62 patients with MS. Compared to patients with other neurological diseases and healthy controls, MS patients had elevated numbers of IFN-gamma, IL-4 and TGF-beta mRNA expressing cells in blood and further augmented in CSF. Although several HLA-Dw2-positive individuals showed very high numbers of cells expressing these cytokines, no significant difference was found in comparison with Dw2-negative patients. However, expression of IL-4 and TGF beta mRNA was significantly increased in patients with shorter duration and minor disability and, for IL-4, in patients still in the relapsing-remitting phase compared to patients with secondary chronic progressive MS. Surprisingly, these changes which favour a beneficial, disease-downregulating effect of IL-4 and TGF-beta in MS, were found to be confined to HLA-Dw2-positive patients. Our findings suggest that the HLA phenotype does not influence the overall level of immune reactivity in MS, but may distinguish subgroups characterized by particular cytokine expression patterns.

Prospective assessment of carotid bifurcation disease with spiral CT angiography in surface shaded display (SSD)-technique

PURPOSE

To decide, whether spiral CT-angiography (CTA) in surface display (SSD)-technique is suitable for accurate quantification of carotid artery stenoses.

MATERIAL AND METHODS

Forty-four patients (25 male, 19 females) with a total of 80 symptomatic carotid artery were studied prospectively with selective cerebral angiography and spiral CTA in SSD-technique. The degree of stenosis was determined according to the NASCET-study.

RESULTS

Assessment of the degree of stenoses with CTA and angiography was the same in 36% of mild stenoses, in 64% of moderate stenoses, in 68% of severe stenoses, and in 95% of the occluded internal carotid arteries. Overall, CTA in SSD-technique showed equivalent results as selective cerebral angiography in 65% of all cases.

CONCLUSION

Spiral CTA in SSD-technique is inferior to selective cerebral angiography. Calcified plaques, vessel opacification and thresholding influence the most grading of stenosis.

Erfahrungen mit einer neuen Technik der lokalen rt-PA-Fibrinolyse

Ziel: Entwicklung eines modifizierten Verfahrens zur lokalen rt-PA-Fibrinolyse, um Kosten, Zeit und applizierte Strahlendosis einzusparen.

Methode: Bei 40 Patienten mit verschlossenen Gefäßsegmenten der BeckenBeinstrombahn im Stadium llb-lll nach Fontaine wurde eine modifizierte lokale rt-PA-Fibrinolyse durchgeführt, 24 Kurzzeitlysen (KL) und 16 Langzeitlysen (LL). Ergebnisse: Die primäre Wiedereröffnungsrate beträgt 75%, die Offenheitsrate im 6-Monate-Follow-up aller primär erfolgreich lysierten Patienten 67%. Der Arm-Knöchel-Index konnte von 0,4 ± 0,3 auf 0,8 ± 0,2 angehoben werden. Die durchschnittliche Belegungszeit des Angiographieraumes betrug 60 min, die mittlere Durchleuchtungszeit 17 min.

Schlußfolgerung: Bei gleicher therapeutischer Wertigkeit bietet die Modifikation gegenüber konventionellen Fibrinolysetechniken Vorteile. Zeitaufwendige KL und LL finden überwiegend außerhalb des Angiographieraumes statt, dieser wird für andere Patienten nutzbar. Die applizierte Strahlendosis wird sowohl für Patienten als auch Personal reduziert.

[CT angiography in the follow-up after carotid endarterectomy]

PURPOSE

To prove the usefulness and clinical value of early CT angiography with maximum intensity projection after carotid endarterectomy: for demonstrating postoperative results.

METHODS

In 16 patients with angiographically confirmed 20 high grade stenoses of internal carotid artery CT angiography was performed before and after carotid surgery within 7 days. The evaluation of successful surgery was related to complete plaque removal and patency of internal carotid artery after endarterectomy based on preoperative CT angiography. Classification of stenosis was performed according to the NASCET study.

RESULTS

In 2/20 cases severe stenoses remained after surgery, which were demonstrated using CT angiography and confirmed by digital subtraction arteriography. 3/20 cases showed mild stenosis and 15/20 were normal.

CONCLUSION

CT angiography is best suited to evaluate results after carotid surgery. The method enables delineation of complete removal of calcified plaque and patency of carotid artery.

Increased mRNA expression of IL-6, IL-10, TNF-alpha, and perforin in blood mononuclear cells in human HIV infection

Evidence has been presented for the involvement of various cytokines, including interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-alpha, in the pathogenesis of human immunodeficiency virus (HIV) infection. Since measured plasma levels may poorly reflect in vivo production of cytokines, we adopted in situ hybridization with cDNA oligonucleotide probes to enumerate blood mononuclear cells (MNCs) expressing mRNA for IL-6, IL-10, TNF-alpha, and perforin. The HIV-infected patients had elevated levels of MNCs expressing mRNA for all four cytokines compared to healthy controls. Numbers of IL-6 mRNA-expressing cells were higher in patients with clinical AIDS than in asymptomatic seropositive patients, and correlated inversely with CD4+ cell counts in blood, reflecting the involvement of IL-6 in later stages of HIV infection. The described approach could be an alternative way to study cytokines in HIV infection.

Theoretical considerations and in vitro results for the development of percutaneous transcatheter balloon embolectomy

RATIONALE AND OBJECTIVES

To prove the feasibility of performing percutaneous transcatheter embolectomy using a funnel-shaped catheter tip and balloon embolectomy catheters.

METHODS

A theoretical model is described to assess the influence of the diameter of an introductory device and coaxially introduced embolectomy catheter. A funnel-shaped catheter tip was attached to 7F, 8F, and 9F introductory sheaths. In vitro embolectomy of 5 g and 12 g thrombi was performed with 3F and 4F embolectomy catheters.

RESULTS

The number of extractions required was significantly related to the ratio of the diameters of the sheaths and embolectomy catheter shafts. The combination of a 7F sheath with a 4F embolectomy catheter required the greatest number of extractions (8.4 +/- 1.7). The least number of extractions was needed for the combination of a 9F sheath with 4F and 3F embolectomy catheters (1.6 +/- 0.7 and 1.8 +/- 0.4, respectively).

CONCLUSIONS

Our results indicate that percutaneous embolectomy with balloon embolectomy catheters is feasible. However, further research is necessary before the final catheter design is chosen.

High numbers of autoantigen-reactive mononuclear cells expressing interferon-gamma (IFN-gamma), IL-4 and transforming growth factor-beta (TGF-beta) are present in cord blood

Umbilical cord blood of neonates and peripheral blood of healthy adults were analysed by in situ hybridization for numbers of mononuclear cells (MNC) expressing the cytokines IFN-gamma, TGF-beta and IL-4 mRNA without culture and after culture in the presence of acetylcholine receptor (AChR), myelin basic protein (MBP) and peripheral myelin protein P2. These antigens were chosen since they represent autoantigens in putatively immune-mediated neurological diseases. The numbers of cells expressing cytokine mRNA after 72 h culture in the presence of AChR, MBP and P2 were higher in cord blood than in peripheral blood of healthy adults. IFN-gamma, TGF-beta and IL-4 were always elevated in parallel. In cord blood there was a pronounced reactivity to several of the tested antigens, while such broad reactivity was not found in peripheral blood of healthy adults. No differences in cytokine mRNA expression were found between cord blood and peripheral blood of adults when cells were analysed without culture. The results show a capacity of cord blood cells to react to several autoantigens by the up-regulation of cytokine mRNA expression.

[Venous stent application with a simultaneous cubitofemoral approach]

In 4 patients with superior inflow obstruction caused by stenosis or occlusion of the central veins it was not possible to pass the guide wire from transfemoral. An additional transbrachial access was applied to avoid the stenosis or occlusions. Patency of the veins from transbrachial was achieved in all cases. After pulling the extensively long guide wire through the still horizontal venous lock, successful Wallstent application was performed from transfemoral in all 4 patients. No peri-interventional or post-interventional complications were seen during 2 days follow-up.