Diversion-p64: results from an international, prospective, multicenter, single-arm post-market study to assess the safety and effectiveness of the p64 flow modulation device

BACKGROUND

The use of flow diversion to treat intracranial aneurysms has increased in recent years.

OBJECTIVE

To assess the safety and angiographic efficacy of the p64 flow modulation device.

METHODS

Diversion-p64 is an international, prospective, multicenter, single-arm, study conducted at 26 centers. The p64 flow modulation device was used to treat anterior circulation aneurysms between December 2015 and January 2019. The primary safety endpoint was the incidence of major stroke or neurologic death at 3-6 months, with the primary efficacy endpoint being complete aneurysm occlusion (Raymond-Roy Occlusion Classification 1) on follow-up angiography.

RESULTS

A total of 420 patients met the eligibility criteria and underwent treatment with the p64 flow modulation device (mean age 55±12.0 years, 86.2% female). Mean aneurysm dome width was 6.99±5.28 mm and neck width 4.47±2.28 mm. Mean number of devices implanted per patient was 1.06±0.47, with adjunctive coiling performed in 14.0% of the cases. At the second angiographic follow-up (mean 375±73 days), available for 343 patients (81.7%), complete aneurysm occlusion was seen in 287 (83.7%) patients. Safety data were available for 413 patients (98.3%) at the first follow-up (mean 145±43 days) with a composite morbidity/mortality rate of 2.42% (n=10).

CONCLUSIONS

Diversion-p64 is the largest prospective study using the p64 flow modulation device. The results of this study demonstrate that the device has a high efficacy and carries a low rate of mortality and permanent morbidity.

Partial breakage of a tunneled dialysis catheter: An uncommon finding

Infections and dysfunction are the most common complications related to catheter use. Here we describe a case of catheter rupture on the course of subcutaneous channel. Catheter fractures are relatively rare, but potentially hazardous complications. In case of partial breakage, a catheter exchange should be a simple solution.

Carotid artery tortuosity may pose a problem during insertion of the tunneled catheter for hemodialysis

Tortuosity of the carotid artery is usually an asymptomatic vascular abnormality and is discovered accidentally during cerebral angiography. These vascular changes may aggravate surgical procedures in the neck region. We described a technique of permanent catheter insertion in patients with renal graft failure in whom renal replacement therapy was necessary. Severe tortuosity of cervical arteries may make this procedure more difficult, necessitating a special technique, that is, full image monitoring.

Pleural effusion with arm, breast, and face edema as a complication of subclavian vein catheterization and arteriovenous fistula in a patient after renal transplantation: A therapeutic approach

A 52-year-old woman after renal transplantation developed unilateral pleural effusion as well as a massive edema of the upper limb, breast, and face as a complication of the subclavian vein catheterization and arteriovenous fistula for hemodialysis. We revealed that impaired venous drainage due to extensive vein occlusion after temporary catheter insertion, together with high venous flow from the arteriovenous fistula, were the explanation. Because of moderately impaired renal graft function and limited availability of vascular access in the patient, fistula ligation as a therapeutic method described in literature, was not an option in our case. The patient underwent an unsuccessful attempt of venous angioplasty, and eventually banding of the fistula and blood flow reduction resolved pleural effusions and edema. This is a reasonable approach to the problem of massive upper torso edema due to central vein occlusion with ipsilateral arteriovenous fistula.

Intra-arterial computed tomography angiography with ultra-low volume of iodine contrast and stent implantation in transplant renal artery stenosis in terms of contrast-induced kidney injury - a preliminary report

PURPOSE

Traditional digital subtraction angiography is still regarded as the gold standard in the diagnostics of transplant renal artery stenosis (TRAS). However, this procedure requires a high volume of iodine contrast medium for optimal visualisation of the renal artery. The aim of this study was to analyse both the usefulness and the safety of intra-arterial computed tomography angiography (IA-CTA) with ultra-low-volume iodine contrast administration in the diagnostic and therapeutic management of TRAS in patients with impaired renal transplant function.

MATERIAL AND METHODS

Thirty-three patients with a suspicion of TRAS based on Doppler-ultrasound and clinical setting underwent IA-CTA with ultra-low iodine contrast volume. A special, author-elaborated CTA protocol was used. The volume of 8-18 ml of diluted iodine contrast medium was administered through a catheter with the tip placed 2 cm below the aortic bifurcation.

RESULTS

In six patients the CTA examinations revealed TRAS in three configurations: in the anastomosis, in the trunk (critical and high-grade), or in both sections. Stenoses were treated with primary stenting obtaining favourable anatomical outcome. No intervention-related complications were observed. No contrast-induced acute kidney injury was diagnosed in this study. Mean serum creatinine concentration was 2.93 ± 0.89 mg/dl at the baseline and 2.89 ± 1.73 mg/dl and 2.17 ± 0.51 mg/dl after three and seven days from IA-CTA, respectively.

CONCLUSIONS

Intra-arterial CTA with ultra-low volume of iodine contrast seems to be a safe and reliable diagnostic tool to detect and assess TRAS in the aspect of stent implantation. Application of this imaging modality eliminates the need for a high volume of iodine contrast and thus does not adversely influence renal transplant function.

Mechanical thrombectomy in acute stroke - Five years of experience in Poland

OBJECTIVES

Mechanical thrombectomy (MT) is not reimbursed by the Polish public health system. We present a description of 5 years of experience with MT in acute stroke in Comprehensive Stroke Centers (CSCs) in Poland.

METHODS AND RESULTS

We retrospectively analyzed the results of a structured questionnaire from 23 out of 25 identified CSCs and 22 data sets that include 61 clinical, radiological and outcome measures.

RESULTS

Most of the CSCs (74%) were founded at University Hospitals and most (65.2%) work round the clock. In 78.3% of them, the working teams are composed of neurologists and neuro-radiologists. All CSCs perform CT and angio-CT before MT. In total 586 patients were subjected to MT and data from 531 of them were analyzed. Mean time laps from stroke onset to groin puncture was 250±99min. 90.3% of the studied patients had MT within 6h from stroke onset; 59.3% of them were treated with IV rt-PA prior to MT; 15.1% had IA rt-PA during MT and 4.7% - emergent stenting of a large vessel. M1 of MCA was occluded in 47.8% of cases. The Solitaire device was used in 53% of cases. Successful recanalization (TICI2b-TICI3) was achieved in 64.6% of cases and 53.4% of patients did not experience hemorrhagic transformation. Clinical improvement on discharge was noticed in 53.7% of cases, futile recanalization - in 30.7%, mRS of 0-2 - in 31.4% and mRS of 6 in 22% of cases.

CONCLUSION

Our results can help harmonize standards for MT in Poland according to international guidelines.

Combined use of a pCONus and a Solitaire stent: Report of two cases

Objective The aim of this study was to report our initial experience of the use of the pCONus neck protection device in conjunction with the Solitaire AB stent to assist in the endovascular management of complex intracranial aneurysms with arteries arising from both the neck and the dome of the aneurysm. Methods Two patients with unruptured aneurysms underwent elective endovascular management of their aneurysms, one arising from the middle cerebral artery bifurcation and one from the anterior communicating artery. Both aneurysms had vessels arising from the neck and dome of the aneurysm. We present the strategy involved to protect all the arterial branches and coil occlude the aneurysm, the angiographic appearances and clinical status of the patients. Results Both cases involved the combined use of a pCONus and Solitaire stent. The parent vessel and efferent branches were all preserved with exclusion of the aneurysm from the circulation. There were no intraoperative complications. One patient developed mild transient symptoms 24 hours post procedure, which had resolved completely on discharge. Conclusion The use of the pCONus in conjunction with the Solitaire stent is a useful combination when dealing with complex wide-necked aneurysms with arteries derived from the fundus of the aneurysm.

Intraarterial CT Angiography Using Ultra Low Volume of Iodine Contrast - Own Experiences

Background

High volume of intravenous contrast in CT-angiography may result in contrast-induced nephropathy. Intraarterial ultra-low volume of contrast medium results in its satisfactory blood concentration with potentially good image quality. The first main purpose was to assess the influence of the method on function of transplanted kidney in patients with impaired graft function. The second main purpose of the study was to evaluate the usefulness of this method for detection of gastrointestinal and head-and-neck haemorrhages.

Material/Methods

Between 2010 and 2013 intraarterial CT-angiography was performed in 56 patients, including 28 with chronic kidney disease (CKD). There were three main subgroups: 18 patients after kidney transplantation, 10 patients with gastrointestinal hemorrhage, 8 patients with head-and-neck hemorrhage. Contralateral or ipsilateral inguinal arterial approach was performed. The 4-French vascular sheaths and 4F-catheters were introduced under fluoroscopy. Intraarterial CT was performed using 64-slice scanner. The scanning protocol was as follows: slice thickness 0.625 mm, pitch 1.3, gantry rotation 0.6 sec., scanning delay 1–2 sec. The extent of the study was established on the basis of scout image. In patients with CKD 6–8 mL of Iodixanol (320 mg/mL) diluted with saline to 18–24 mL was administered at a speed of 4–5 mL/s.

Results

Vasculature was properly visualized in all patients. In patients with impaired renal function creatinine/eGFR levels remained stable in all but one case. Traditional arteriography failed and CT-angiography demonstrated the site of bleeding in 3 of 10 patients with symptoms of gastrointestinal bleeding (30%). In 8 patients with head-and-neck bleeding CT-angiography did not prove beneficial when compared to traditional arteriography.

Conclusions

1. Ultra-low contrast intraarterial CT-angiography does not deteriorate the function of transplanted kidneys in patients with impaired graft function. 2. 3D reconstructions allow for excellent visualization of vascular anatomy of renal transplants. 3. Intraarterial CT-angiography is useful for detection of the bleeding site.

Analysis of metabolic changes of brain in HIV-1 seropositive patients with proton magnetic resonance spectroscopy

BACKGROUND

Asymptomatic central nervous system involvement may occur in the early stages of the HIV infection. The aim of the study was to evaluate early brain metabolic changes by means of proton MR spectroscopy (H1MRS) in the HIV-1 seropositive patients without neurological deficits or significant abnormalities in the plain MR study.

MATERIAL/METHODS

The H1MRS examinations were performed with the use of a MR GE Signa 1,5T system. There were 39 subjects examined, aged 21 to 57 years (mean age 35 years) were examined, including 25 patients infected with HIV-1 and 14 healthy volunteers who constituted a control group. The examinations were performed using the Single Voxel Spectroscopy technique with the PRESS sequence, with following parameters: TR=1500 ms, TE=35 ms, number of acquisitions =128, time of acquisition =3 min. 43 sec. Voxels of 8 cm(3) (20×20×20 mm) in size were located in the following 5 regions: posterior cingulate gyrus, grey matter of the frontal area, left basal ganglia, white matter of the left parietal area and white matter of the frontal area. The NAA/Cr, Cho/Cr, mI/Cr ratios in the defined regions of interest were statistically analyzed.

RESULTS

There was a statistically significant decrease (p<0.05) in the NAA/Cr ratios in the posterior cingulate area and white matter of the left parietal area in HIV-1 seropositive patients, as compared to the control group. Other metabolite ratios in all the above mentioned locations showed no statistically significant differences, as was also the case for NAA/Cr ratios in grey matter of the frontal area, left basal ganglia and white matter of the frontal area.

CONCLUSIONS

The reduction of NAA/Cr values revealed in H1MRS studies suggests loss of neurons/neuronal activity in the posterior cingulate area and white matter of the left parietal area, in patients with HIV-1 at the stage before clinical manifestations of retroviral infection and structural changes in the plain MR study. This may reflect a direct neurotropic activity of HIV.

Comparison of serological and molecular (PCR-SSP) techniques of HLA-DR typing in clinical laboratory routine

Advances in molecular biology techniques allowed for introduction of PCR-based methods for HLA typing. In routine HLA typing for organ transplantation serological method is still being used as a standard, although molecular techniques are applied more and more often. The aim of our study was to compare HLA-DR typing using traditional serological method and PCR-SSP methodology in routine clinical laboratory. HLA-DR typing was performed using standard microcytotoxicity assay and PCR-SSP method in 28 patients referred to our Transplantation Immunology Unit for HLA typing. Comparison of results obtained by both methods revealed no discrepancies in 5 patients, in 12 patients the PCR-SSP typing showed additional DR antigens or splits of antigens. In 11 patients serological typing turned out to be impossible because of technical problems. Molecular PCR typing allowed for precise antigen determination in all the patients. Comparing both methods we found PCR-SSP HLA typing method very useful in routine HLA-DR determination, especially valuable in patients, in whom some problems in serological testing are expected.