Safety and efficacy of superior rectal artery embolization with particles and metallic coils for the treatment of hemorrhoids (Emborrhoid technique)

PURPOSE

The purpose of this study was to comprehensively evaluate the short-term outcomes after percutaneous embolization of the superior rectal artery (SRA) with metallic coils and particles for the management of hemorrhoids.

MATERIALS AND METHODS

Forty patients (15 men, 25 women) with a mean age of 35±5 years (SD) (range: 25-65 years) were prospectively enrolled. All patients had symptomatic hemorrhoids. The distribution of internal hemorrhoids was as follows: grade I (n=6, 16%); grade II (n=28, 69%) and grade III (n=6; 15%). All patients had percutaneous embolization of the SRA with metallic coils and synthetic polyvinyl alcohol particles. Follow-up evaluation included clinical examination, rectoscopy, histopathological analysis of rectal mucosa, duplex Doppler blood flow quantification, electromyography, sphincterometry of the anal sphincter and analysis of patient satisfaction.

RESULTS

No immediate complications were observed and no patients had anal pain syndrome after embolization. Hemorrhoids showed a 43% size reduction after embolization (P<0.05). Taking into account the symptom resolutions such as irritation, discomfort, bloody discharge and pain, satisfaction was observed in 5/6 (83%) patients with grade III hemorrhoids and 32/34 patients (94%) with grades I-II hemorrhoids. One month after embolization, anal sphincter contractility normalized and no changes in anal electromyography were observed. Blood flow in the hemorrhoidal plexus dropped from 109±1.2ml/min/100g (SD) before treatment to 60.2±4.4ml/min/100g (SD) (P<0.05) the day after embolization and remained unchanged one month after embolization.

CONCLUSION

Our study demonstrates that embolization of SRA with particle and coils does not lead to ischemia in patients with symptomatic hemorrhoids. Short-term results with regard to symptom management for hemorrhoidal disease are very encouraging and should stimulate further prospective and multicenter studies.

Preclinical study on an animal model of a new non-adhesive cyanoacrylate (Purefill®) for arterial embolization

PURPOSE

The goal of this study was to assess the distal dispersion, the adhesion strength to catheter, the vascular toxicity and the ability in excluding embolized vessels using Purefill^® (α-hexil-cyanoacrylate) as embolic material, which is a new high purity cyanoacrylate and compare these results with those obtained with N-butyl-2-cyanoacrylate (Histoacryl^®) and a mixture of N-butyl-2-cyanoacrylate and methacryloxysulfolane.

MATERIAL AND METHODS

In six pigs, the right rete mirabile (RM) and right renal arteries were embolized with α-hexil-cyanoacrylate, and the left rete mirabile and left renal artery were embolized with N-butyl-2-cyanoacrylate and N-butyl-2-cyanoacrylate+Methacryloxysulfolane for comparison. One minute after glue injection through the microcatheter, displacements of the kidney and the pharyngeal artery were measured on angiographic images, before exercising any traction and during catheter pulling, when the forces were maximal. Displacement was measured in terms of distance (mm) with respect to renal pedicles and in terms of angle (°) with respect to the rete. After acute embolization (4 pigs) or three-month follow-up (2 pigs), the kidneys and the RM were removed and further analysed using computed tomography and histopathological examination.

RESULTS

Similar short and long-term embolic efficacies were observed with the three glues. The mean displacement distances of renal pedicles were 2.6mm for α-hexil-cyanoacrylate, 22.6mm for N-butyl-2-cyanoacrylate and 19.8mm for N-butyl-2-cyanoacrylate+Methacryloxysulfolane (P=0.021). The mean angles of displacement of the ascending pharyngeal arteries were for 12.2° for α-hexil-cyanoacrylate, 23.5° for N-butyl-2-cyanoacrylate and 30° for N-butyl-2-cyanoacrylate+Methacryloxysulfolane (P=0.070). Histopathologically, findings were similar for the three glues, immediately and 90 days after embolization.

CONCLUSION

α-hexil-cyanoacrylate has occlusive efficacy in the short and long term similar to those of N-butyl-2-cyanoacrylate and N-butyl-2-cyanoacrylate+Methacryloxysulfolane. In addition, histopathological changes are similar with the three glues immediately or 90 days after embolization. Conversely, α-hexil-cyanoacrylate results in a reduced angle and distance of displacement compared to the other two glues, assumably reflecting a limited adhesive strength.

Chronic Melatonin Administration Reduced Oxidative Damage and Cellular Senescence in the Hippocampus of a Mouse Model of Down Syndrome

Previous studies have demonstrated that melatonin administration improves spatial learning and memory and hippocampal long-term potentiation in the adult Ts65Dn (TS) mouse, a model of Down syndrome (DS). This functional benefit of melatonin was accompanied by protection from cholinergic neurodegeneration and the attenuation of several hippocampal neuromorphological alterations in TS mice. Because oxidative stress contributes to the progression of cognitive deficits and neurodegeneration in DS, this study evaluates the antioxidant effects of melatonin in the brains of TS mice. Melatonin was administered to TS and control mice from 6 to 12 months of age and its effects on the oxidative state and levels of cellular senescence were evaluated. Melatonin treatment induced antioxidant and antiaging effects in the hippocampus of adult TS mice. Although melatonin administration did not regulate the activities of the main antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione S-transferase) in the cortex or hippocampus, melatonin decreased protein and lipid oxidative damage by reducing the thiobarbituric acid reactive substances (TBARS) and protein carbonyls (PC) levels in the TS hippocampus due to its ability to act as a free radical scavenger. Consistent with this reduction in oxidative stress, melatonin also decreased hippocampal senescence in TS animals by normalizing the density of senescence-associated β-galactosidase positive cells in the hippocampus. These results showed that this treatment attenuated the oxidative damage and cellular senescence in the brain of TS mice and support the use of melatonin as a potential therapeutic agent for age-related cognitive deficits and neurodegeneration in adults with DS.

Development and initial evaluation of a training program for peripherally inserted central catheter (PICC) placement for radiology residents and technicians

OBJECTIVES

The goals of this study were to develop and evaluate a joint theoretical/practical training course for radiology residents and technicians and to start a collaborative practice agreement enabling radiology technicians to perform PICC placement under the responsibility of an interventional radiologist.

MATERIALS AND METHODS

A joint training session based on literature evidences and international recommendations was designed. Participants were assessed before and after training, and were also asked to evaluate the program one month after completion of the training course. Practical post-training mentoring guidelines were laid down for radiologists supervising technicians.

RESULTS

From January to April 2014, 6 radiology residents and 12 radiology technicians from the two interventional radiology departments of the University hospitals in Marseille took part in the training program. For both residents and technicians, significant improvement was observed between pretraining and post-training assessment. The majority of participants were satisfied with the program.

CONCLUSION

Our experience suggests that combined theoretical and practical training in PICC placement allows improving technical skill and yields high degrees of satisfaction for both radiology residents and technicians. A collaborative practice agreement is now formally established to enable radiologists to delegate PICC placement procedures to radiology technicians.

The presence of spontaneous portosystemic shunts increases the risk of complications after transjugular intrahepatic portosystemic shunt (TIPS) placement

PURPOSE

The goal of this study was to identify clinical and imaging variables that are associated with an unfavorable outcome during the 30 days following transjugular intrahepatic portosystemic shunt (TIPS) placement.

MATERIAL AND METHODS

Fifty-four consecutive patients with liver cirrhosis (Child-Pugh 6-13, Model for End-stage Liver Disease 7-26) underwent TIPS placement for refractory ascites (n=25), recurrent or uncontrolled variceal bleeding (n=23) or both (n=6). Clinical, biological and imaging variables including type of stent (covered n=40; bare-stent n=14), presence of spontaneous portosystemic shunt (n=31), and variations in portosystemic pressure gradient were recorded. Early severe complication was defined as the occurrence of overt hepatic encephalopathy or death within the 30days following TIPS placement.

RESULTS

Sixteen patients (30%) presented with early severe complication after TIPS placement. Child-Pugh score was independently associated with complication (HR=1.52, P<0.001). Among the imaging variables, opacification of spontaneous portosystemic shunt during TIPS placement but before its creation was associated with an increased risk of early complication (P=0.04). The other imaging variables were not associated with occurrence of complication.

CONCLUSION

Identification of spontaneous portosystemic shunt during TIPS placement reflects the presence of varices and is associated with an increased risk of early severe complication.

MR imaging of arrhythmogenic right ventricular dysplasia: What the radiologist needs to know

Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is an inherited heart muscle disease that predominantly affects the right ventricle. Clinical manifestations are related to severe ventricular arrhythmia that may lead to sudden death, mostly in young patients. Magnetic resonance imaging (MRI), included in the new diagnostic criteria since 2010, aims to detect segmental and global wall motion abnormalities, reduced ejection fraction, right ventricular dilatation and right ventricular diastolic/systolic dysfunction. An MRI assessment of the right ventricle is often challenging, partly because the MRI diagnostic criteria have some limitations, and also because it requires a significant learning curve due to the low prevalence of the disease. Therefore, this article aims to review the pathophysiology of the disease, the cardiac MRI protocol, images of the various stages of this affection as well as the differential diagnosis.

Emborrhoid: a new concept for the treatment of hemorrhoids with arterial embolization: the first 14 cases

PURPOSE

The 'emborrhoid' technique consists of the embolization of the hemorrhoidal arteries. The endovascular arterial occlusion is performed using coils placed in the terminal branches of the superior rectal arteries. The emborrhoid technique has been modeled after elective transanal Doppler-guided hemorrhoidal artery ligation which has been shown to be effective in hemorrhoidal disease. We report the first 14 cases of our experience with emborrhoid technique.

MATERIALS AND METHODS

Fourteen patients with disabling chronic rectal bleeding were treated using the emborrhoid technique (3 women, 11 men). The stage of the hemorrhoidal disease was II (10 patients), III (3), and IV (1). This treatment was decided by a multidisciplinary team (proctologist, visceral surgeon, and radiologist). Seven patients underwent previous proctological surgery. Ten patients had coagulation disorders (anticoagulants or cirrhosis). Superior rectal arteries were embolized with pushable microcoils (0.018).

RESULTS

Technical success of the embolization procedure was 100 %. Clinical success at 1 month was 72 % (10/14). Of the 4 patients who experienced rebleeding, two underwent additional embolization of the posterior rectal arteries with success. No pain or ischemic complications were observed in 13 patients. One patient experienced a temporary painful and edematous, perianal reaction.

CONCLUSION

Our case studies suggest that coil embolization of the superior rectal arteries is technically feasible, safe and well tolerated. Additional studies are needed to evaluate the efficacy of this new 'emborrhoid' technique in the management of hemorrhoidal disease.

Overexpression of Dyrk1A is implicated in several cognitive, electrophysiological and neuromorphological alterations found in a mouse model of Down syndrome

Down syndrome (DS) phenotypes result from the overexpression of several dosage-sensitive genes. The DYRK1A (dual-specificity tyrosine-(Y)-phosphorylation regulated kinase 1A) gene, which has been implicated in the behavioral and neuronal alterations that are characteristic of DS, plays a role in neuronal progenitor proliferation, neuronal differentiation and long-term potentiation (LTP) mechanisms that contribute to the cognitive deficits found in DS. The purpose of this study was to evaluate the effect of Dyrk1A overexpression on the behavioral and cognitive alterations in the Ts65Dn (TS) mouse model, which is the most commonly utilized mouse model of DS, as well as on several neuromorphological and electrophysiological properties proposed to underlie these deficits. In this study, we analyzed the phenotypic differences in the progeny obtained from crosses of TS females and heterozygous Dyrk1A (+/-) male mice. Our results revealed that normalization of the Dyrk1A copy number in TS mice improved working and reference memory based on the Morris water maze and contextual conditioning based on the fear conditioning test and rescued hippocampal LTP. Concomitant with these functional improvements, normalization of the Dyrk1A expression level in TS mice restored the proliferation and differentiation of hippocampal cells in the adult dentate gyrus (DG) and the density of GABAergic and glutamatergic synapse markers in the molecular layer of the hippocampus. However, normalization of the Dyrk1A gene dosage did not affect other structural (e.g., the density of mature hippocampal granule cells, the DG volume and the subgranular zone area) or behavioral (i.e., hyperactivity/attention) alterations found in the TS mouse. These results suggest that Dyrk1A overexpression is involved in some of the cognitive, electrophysiological and neuromorphological alterations, but not in the structural alterations found in DS, and suggest that pharmacological strategies targeting this gene may improve the treatment of DS-associated learning disabilities.

Minimal portal vein stenosis is a promising preconditioning in living donor liver transplantation in porcine model

BACKGROUND & AIMS

The main hindrance in promoting living donor liver transplantation remains the morbi-mortality risk for the donor. Considering the opposed remodeling influence of portal and hepatic artery flows, our working hypothesis was to identify a lobar portal vein stenosis capable of inducing a contralateral liver mass compensatory enlargement, without the downstream ipsilateral atrophic response.

METHODS

Twenty-four pigs entered this study. Six of them were used to establish hemodynamic changes following a progressive left portal vein (LPV) stenosis, in blood flow, pressure and vessel diameter of the LPV, main portal vein and hepatic artery. Sixteen pigs were divided into 4 groups: sham operated animals, 20% LPV stenosis, 50% LPV stenosis, and 100% LPV stenosis. Daily liver biopsies were collected until post-operative day 5 to investigate liver regeneration and atrophy (Ki67, STAT3, LC3, and activated caspase 3) according to the degree of LPV stenosis. Finally, changes in liver volumetry after 20% LPVS were investigated.

RESULTS

A 20% LPV stenosis led to dilatation of the hepatic artery and a subsequent four-fold increase in hepatic arterial flow. Concomitantly, liver regeneration was triggered in the non-ligated lobe and the cell proliferation peak, 5 days after surgery, was comparable to that obtained after total LPV ligation. Moreover, 20% LPV stenosis preconditioning did not induce left liver atrophy contrary to 50 and 100% LPV stenosis.

CONCLUSIONS

A 20% LPV stenosis seems to be the adequate preconditioning to get the remnant liver of living donor ready to take on graft harvesting without atrophy of the future graft.

Changes in the brain and plasma Aβ peptide levels with age and its relationship with cognitive impairment in the APPswe/PS1dE9 mouse model of Alzheimer's disease

Double transgenic mice expressing mutant amyloid precursor protein (APPswe) and mutant presenilin 1 (PS1dE9) are a model of Alzheimer-type amyloidosis and are widely used in experimental studies. In the present work, the relationships between brain and plasma amyloid-β peptide (Aβ) levels and cognitive impairments were examined in male APPswe/PS1dE9 double transgenic mice at different ages. When compared with non-transgenic littermates, APPswe/PS1dE9 mice exhibited significant learning deficits from the age of 6months (M6), which were aggravated at later stages of life (M8 and M12). Sporadic brain amyloid plaques were observed in mice as early as M3 and progressively increased in number and size up to M12. A similar increase was observed in brain insoluble Aβ levels as assessed by enzyme-linked immunosorbent assay (ELISA). In particular, the levels of brain insoluble Aβ peptides rose steeply from M4 to M6. Interestingly, this pronounced amyloid deposition was accompanied by a temporary fall in the concentration of brain soluble and membrane-bound Aβ peptides at M6 that rose again at M8 and M12. The plasma levels of Aβ40 and Aβ42 decreased with advancing age up to M8, when they stabilized at M12. This decrease in plasma Aβ levels coincided with the observed increase in insoluble brain Aβ levels. These results could be useful for developing plasma Aβ levels as possible biomarkers of the cerebral amyloidosis and provide advances in the knowledge of the Aβ peptide biochemical changes that occur in the brain of Alzheimer's disease patients.

Chronic melatonin treatment rescues electrophysiological and neuromorphological deficits in a mouse model of Down syndrome

The Ts65Dn mouse (TS), the most commonly used model of Down syndrome (DS), exhibits several key phenotypic characteristics of this condition. In particular, these animals present hypocellularity in different areas of their CNS due to impaired neurogenesis and have alterations in synaptic plasticity that compromise their cognitive performance. In addition, increases in oxidative stress during adulthood contribute to the age-related progression of cognitive and neuronal deterioration. We have previously demonstrated that chronic melatonin treatment improves learning and memory and reduces cholinergic neurodegeneration in TS mice. However, the molecular and physiological mechanisms that mediate these beneficial cognitive effects are not yet fully understood. In this study, we analyzed the effects of chronic melatonin treatment on different mechanisms that have been proposed to underlie the cognitive impairments observed in TS mice: reduced neurogenesis, altered synaptic plasticity, enhanced synaptic inhibition and oxidative damage. Chronic melatonin treatment rescued both impaired adult neurogenesis and the decreased density of hippocampal granule cells in trisomic mice. In addition, melatonin administration reduced synaptic inhibition in TS mice by increasing the density and/or activity of glutamatergic synapses in the hippocampus. These effects were accompanied by a full recovery of hippocampal LTP in trisomic animals. Finally, melatonin treatment decreased the levels of lipid peroxidation in the hippocampus of TS mice. These results indicate that the cognitive-enhancing effects of melatonin in adult TS mice could be mediated by the normalization of their electrophysiological and neuromorphological abnormalities and suggest that melatonin represents an effective treatment in retarding the progression of DS neuropathology.

Long-term oral administration of melatonin improves spatial learning and memory and protects against cholinergic degeneration in middle-aged Ts65Dn mice, a model of Down syndrome

Ts65Dn mice (TS), the most commonly used model of Down syndrome (DS), exhibit phenotypic characteristics of this condition. Both TS mice and DS individuals present cognitive disturbances, age-related cholinergic degeneration, and increased brain expression of β-amyloid precursor protein (AβPP). These neurodegenerative processes may contribute to the progressive cognitive decline observed in DS. Melatonin is a pineal indoleamine that has been reported to reduce neurodegenerative processes and improve cognitive deficits in various animal models. In this study, we evaluated the potentially beneficial effects of long-term melatonin treatment on the cognitive deficits, cholinergic degeneration, and enhanced AβPP and β-amyloid levels of TS mice. Melatonin was administered for 5 months to 5- to 6-month-old TS and control (CO) mice. Melatonin treatment improved spatial learning and memory and increased the number of choline acetyltransferase (ChAT)-positive cells in the medial septum of both TS and CO mice. However, melatonin treatment did not significantly reduce AβPP or β-amyloid levels in the cortex or the hippocampus of TS mice. Melatonin administration did reduce anxiety in TS mice without inducing sensorimotor alterations, indicating that prolonged treatment with this indoleamine is devoid of noncognitive behavioral side effects (e.g., motor coordination, sensorimotor abilities, or spontaneous activity). Our results suggest that melatonin administration might improve the cognitive abilities of both TS and CO mice, at least partially, by reducing the age-related degeneration of basal forebrain cholinergic neurons. Thus, chronic melatonin supplementation may be an effective treatment for delaying the age-related progression of cognitive deterioration found in DS.

An experimental porcine model of heterotopic renal autotransplantation

OBJECTIVE

The aim of the present study was to validate an experimental model of heterotopic renal allotransplantation. Such a model, more relevant to the human situation, has never been previously described.

MATERIALS AND METHODS

Pietrin pigs (40 to 50 kg) were used in the study. Through a midline incision, the left kidney was removed, washed, and preserved in a standard preservation solution (Celsior, Genzyme, France) for 20 hours at 4 °C. Heterotopic autotransplantation was performed into the right iliac fossa onto the external iliac vessels with an end-to-side anastomosis and a nonstented uretero-ureteral anastomosis was performed.

RESULTS

Twenty-five renal allotransplantations were performed over a 5-month time period. Mean operating time progressively decreased and stabilized after 15 procedures (mean ± SD: 78.2 ± 19 minutes and 187.4 ± 18 minutes for left nephrectomy and transplantation, respectively) as morbidity decreased concomitantly. Suturing times for end-to-side anastomosis of the renal artery and vein onto the external iliac artery and vein were 21.9 ± 7 minutes and 34 ± 8 minutes (mean ± SD), respectively. Ten pigs died before the end of the experiment.

CONCLUSIONS

We have developed and validated the first nonrodent animal model of heterotopic renal autotransplantation relevant to the human anatomy and physiology. The procedure was easy to learn and safe. This model could be used to teach junior surgeons renal transplantation techniques and could also be used as a model to study ischemia-reperfusion injury in renal transplantation.

[Pathological features of radiofrequency ablation (RFA) renal scar CT-imaging in a swine model]

PURPOSE

To analyze the changes in vicinal kidney parenchyma after percutaneous RFA.

MATERIALS AND METHODS

[corrected] Twenty-four CT-guided RFA procedures were performed on six pigs using 2 cm LeVeen coaxial needles. We studied volume, morphology, cavitation and enhancement of the ablation zones (AZ) before and after the procedure on contrast-injected CT-scans. The kidneys were removed four weeks later and studied in the path lab.

RESULTS

All the procedures were successfully completed. Four weeks later, the CT-scans showed AZ that were either clearly circumscribed or with unclear borders, heterogenous areas associating necrosis and infarct tissue and mesenchyma showing a process of apoptosis around the edges. A treatment considered as incomplete on the CT-scan (presenting as an enhancement) was always associated with necrosis on the histology slides, although the necrotic areas behaved in various different ways on the CT-scan after injection of contrast medium: an enhancement of more than 10 HU did not mean that no necrotic tissue was present.

CONCLUSION

RFA causes heterogenous tissue changes, associating necrotic and ischemic zones and an apoptotic reaction. The mechanisms of these changes and their therapeutic significance should be studied. CT-scans performed immediately after RFA procedure and one month later are not predictive of the efficacy of the treatment because an enhancement of the AZ does not mean that it is not necrotic. The value of a CT-scan performed one month after the procedure is debatable, because the tissue remodeling that occurs in the kidneys is not definitive at this time-point.