Brain aneurysms and arteriovenous malformations: advancements and emerging treatments in endovascular embolization

BACKGROUND AND PURPOSE: Brain aneurysms and vascular malformations can cause cerebral hemorrhages, with devastating consequences for the patients and their families. Since the development of microcatheters and materials used for endovascular embolization, we have witnessed a rapid advancement in the technology and in the number or patients treated with this approach. The aim of this review is to survey recent data relevant to new technologies and emerging treatment strategies in these areas. SUMMARY OF REVIEW: Clinical trials assessing the safety and efficacy of coil embolization for cerebral aneurysms were based on the use of bare platinum, helical coils. Since then, endovascular operators have been testing and using new materials such as bioactive coils, expandable coils, and complex-shaped coils. Based on the data so far obtained, third and fourth generation coil designs are rapidly emerging and will be ready for clinical application in the near future. Balloon- and stent-assisted coil embolization is enabling the treatment of complex, large-neck aneurysms and the vascular reconstruction of lesions previously considered not treatable. New open- and closed-cell designs allow the navigation and deployment of stents in extremely tortuous vessels. With regards to the embolization of vascular malformations, it is possible to safely navigate microcatheters and microwires through very small arteries previously considered not accessible. In addition, embolization materials such as n-butyl cyanoacrylate and ethylene-vinyl alcohol copolymer are now routinely injected to safely reduce or obliterate large and complex arteriovenous malformations and fistulae. CONCLUSIONS: Advancements in technology are rapidly improving the endovascular approach to the treatment of cerebral aneurysms and arteriovenous malformations

Role of laparoscopy in the diagnosis and management of benign adnexal masses

Background: Adnexal masses are frequent findings in women of all age groups. It consists of the ovaries, fallopian tubes and uterine ligaments. Women can present with various gynaecological complaints and adnexal masses could be detected while examining and investigating for these complaints. The aim was to study the role of laparoscopy in diagnosis and management of benign adnexal masses.Methods: The study was conducted on 48 women of reproductive age group. Per speculum examination was done and PAP smear was taken before bimanual examination was done. A complete per vaginum examination was done and the adnexal mass was assessed for its size, side, consistency, laterality and tenderness. Laparoscopy was done to confirm preoperative diagnosis and appropriate procedure done depending on diagnosis.Results: Pain in the lower abdomen was the commonest chief complaint seen in 87.5% cases. 41.67% cases were suspected to have endometriosis while on laparoscopy it was seen in 47.92%, 33.33% were suspected to have ovarian cyst which decreased to 25% on laparoscopy, ectopic pregnancy in 16.67% cases both pre-operative and on laparoscopic examination and tubo-ovarian mass in 8.33% cases pre-operatively and 2.08% on laparoscopy.Conclusions: This study has shown that if proper preoperative evaluation was done, author can select the appropriate patients for laparoscopic approach

Clinical profile of patients with pelvic adnexal masses

Background: Adnexal masses are frequent findings in women of all age groups. It consists of the ovaries, fallopian tubes and uterine ligaments. Women can present with various gynaecological complaints and adnexal masses could be detected while examining and investigating for these complaints. Aim was to study the clinical profile of women in reproductive age group presented with adnexal masses.Methods: The study comprised of 48 women of reproductive age group. Per speculum examination was done and PAP smear was taken before bimanual examination was done.A complete per vaginum examination was done and the adnexal mass was assessed for its size, side, consistency, laterality and tenderness.Results: Pain in the lower abdomen was the commonest chief complaint seen in 87.5% cases. Out of these, majority i.e.66.67% had chronic pelvic pain and 23% had pain of less than 1-month duration which were cases of ectopic pregnancy. 41.67% cases were suspected to have endometriosis,33.33% were suspected to have ovarian cyst, followed by ectopic pregnancy in 16.67% cases and tubo-ovarian mass in 8.33% cases.Conclusions: The present study shows that if proper preoperative evaluation is done, we can select the appropriate patients for laparoscopic approach

Effectiveness of mechanical endovascular thrombectomy in a model system of cerebrovascular occlusion

BACKGROUND AND PURPOSE: A number of thrombectomy devices are currently undergoing clinical evaluation; meanwhile, various novel devices are under investigation. The aims of this study were to quantify flow restoration and the particle size distribution of the effluent pursuant to MET in an in vitro occlusion model. MATERIALS AND METHODS: The model system was composed of 3 elements: an ICA/MCA replica, a clot model with mechanical properties similar to those of thrombi found in patients at risk of stroke, and a pulsatile flow loop. Different thrombectomy mechanisms including mechanical retrieval, aspiration, and waveguide induced cavitation were used. The efficacy end points were recanalization rate and amount of flow restoration. The risk of the embolic shower was assessed to evaluate device safety. RESULTS: The recanalization rates were the following: Merci, 67%; Solitaire, 100%; Penumbra, 83%; Enterprise, 17%; and the waveguide, 0%. In experiments in which recanalization was achieved, the amount of flow restoration for the Merci, Solitaire, and Enterprise devices was 100%, 92%, and 86%, respectively. The mean sizes of generated small and large clot fragments were between 23 and 37 and 215 and 285 mum, respectively, depending on the device used. The Merci device generated the fewest number of large fragments compared with the Penumbra system (P \u3c .05) and Solitaire (not significant). CONCLUSIONS: The risk of embolic shower was influenced by the mechanism of action for the thrombectomy device. Clinically reported recanalization rates for the Solitaire, Penumbra, and Merci devices were nearly identical in this model system, suggesting that this model may provide a predictive tool for preclinical evaluation of MET

Techniques in distal access of wide-necked giant intracranial aneurysms during treatment with flow diversion

BACKGROUND: Accessing the normal distal vessel in treatment of wide-necked giant intracranial aneurysms with flow diversion can be difficult. CASE DESCRIPTION: Through illustrative cases, the authors present several useful techniques in distal access of wide-necked giant aneurysms during flow diversion treatment. Obtaining an optimal projection that separates the outflow limb from the aneurysm is most critical. Each of the three techniques described enabled the distal access to giant intracranial aneurysms during treatment with flow diversion. CONCLUSION: The looped-around technique, balloon-assisted technique, and retrograde access are valuable strategies in crossing the aneurysm if direct distal access cannot be obtained

A study of maternal outcome in first trimester bleeding

Background: The outcome of first trimester vaginal bleeding is a matter of debate. Vaginal bleeding is common and potentially alarming symptom in early pregnancy. First trimester bleeding is a common occurrence. It has been estimated to occur in 15-25% of all pregnant women. Objective of this study was to evaluate the various maternal outcomes in women with first trimester bleeding.Methods: This prospective observational study was conducted in the postgraduate department of obstetrics and gynecology, SMGS Hospital, Government Medical College, Jammu, Jammu and Kashmir, India. The study included 200 pregnant women presented with first trimester bleeding. All the women were followed prospectively till delivery and early postpartum period for various outcomes such as preterm delivery, PROM, PPROM, anemia, oligohydramnios, placental abruption, placenta previa and postpartum hemorrhage.Results: Out of 200 patients studied, 19% patients aborted. Ectopic and molar pregnancy was seen in 5% and 1.5% patients respectively. Out of 74.5% patients who continued pregnancy, maternal complications included anemia (52%), PROM (14.09%), oligohydramnios (6.71%), placenta previa (5.37%), PPH (4.03%), PPROM (2.68%), preeclampsia (2.01%), gestational hypertension (1.34%), abruption and post-datism (0.67% each).Conclusions: From the results of this study, it can be concluded that first trimester bleeding can be a predicting factor in terms of mother and infant consequences of pregnancy and it is necessary to increase the knowledge of pregnant women in this regard for closer care

Risk of distal embolization with stent retriever thrombectomy and ADAPT

BACKGROUND: There is a discrepancy in clinical outcomes and the achieved recanalization rates with stent retrievers in the endovascular treatment of ischemic stroke. It is our hypothesis that procedural release of embolic particulate may be one contributor to poor outcomes and is a modifiable risk. The goal of this study is to assess various treatment strategies that reduce the risk of distal emboli. METHODS: Mechanical thrombectomy was simulated in a vascular phantom with collateral circulation. Hard fragment-prone clots (HFC) and soft elastic clots (SECs) were used to generate middle cerebral artery (MCA) occlusions that were retrieved by the Solitaire FR devices through (1) an 8 Fr balloon guide catheter (BGC), (2) a 5 Fr distal access catheter at the proximal aspect of the clot in the MCA (Solumbra), or (3) a 6 Fr guide catheter with the tip at the cervical internal carotid artery (guide catheter, GC). Results from mechanical thrombectomy were compared with those from direct aspiration using the Penumbra 5MAX catheter. The primary endpoint was the size distribution of emboli to the distribution of the middle and anterior cerebral arteries. RESULTS: Solumbra was the most efficient method for reducing HFC fragments (p \u3c 0.05) while BGC was the best method for preventing SEC fragmentation (p \u3c 0.05). The risk of forming HFC distal emboli ( \u3e 1000 microm) was significantly increased using GC. A non-statistically significant benefit of direct aspiration was observed in several subgroups of emboli with size 50-1000 microm. However, compared with the stent-retriever mechanical thrombectomy techniques, direct aspiration significantly increased the risk of SEC fragmentation (microm) by at least twofold. CONCLUSIONS: The risk of distal embolization is affected by the catheterization technique and clot mechanics

Polyglycolide/polylactide-coated platinum coils for patients with ruptured and unruptured cerebral aneurysms: a single-center experience

BACKGROUND AND PURPOSE: Recanalization of cerebral aneurysm is a limitation of bare platinum coils (BPCs). In a swine aneurysm model, polyglycolide/polylactide (a polymer)-coated platinum coils (Matrix) accelerated clot fibrosis and reduced recanalization rate and aneurysmal volume. We aimed to evaluate the safety of Matrix coils in patients with intracranial aneurysm. METHODS: This is a single-center, prospective study of patients with intracranial aneurysms treated with Matrix alone or in combination with BPCs. Follow-up evaluation included a 1-month clinical evaluation and a 6- and 12-month clinical and angiographic examination. Primary adverse events included death, stroke, and permanent neurological deficits. RESULTS: Between May 2002 and January 2004, 52 patients (range 34 to 79 years of age; 38 females) were treated for 54 aneurysms (size 7.9+/-4.6 mm; neck 3.9+/-1.5 mm; 26 ruptured). Matrix alone was used in 13 aneurysms. In 39, we used a combination of Matrix and BPCs. Twenty-one aneurysms had a 6-month follow-up examination (11 Matrix; 10 Matrix combined with bare platinum), and 11 completed the 12-month follow-up evaluation (Matrix only). Adverse events not related to the procedure were 2 deaths (ruptured basilar aneurysms) and 1 stroke at day 10 postcoiling secondary to vasospasm. Procedure-related adverse events were 2 strokes. At 6-month follow-up (n=21) evaluation, 2 of 3 recanalizations needed retreatment. At 12-month follow-up (n=11), there was no recanalization in patients treated with Matrix alone and no significant reduction in aneurysmal size. CONCLUSIONS: Polyglycolide/polylactide-coated coils had a satisfactory safety profile. Significant aneurysmal size reduction after coiling was not observed

Porcine brachial artery tortuosity for in vivo evaluation of neuroendovascular devices

We report a novel model of arterial tortuosity in the porcine brachial artery for testing of endovascular devices in the flexed forelimb position. This provides an ideal vascular territory for an in vivo assessment of guidewires, microcatheters, and endovascular implants because it closely mimics the challenging curvature at the carotid siphon

A thromboembolic model for the efficacy and safety evaluation of combined mechanical and pharmacologic revascularization strategies

BACKGROUND AND PURPOSE: Recanalization strategies mediated by intra-arterial fibrinolytic therapy in combination with mechanical clot disruption may be a more effective treatment approach than either therapy used alone. There are few preclinical animal models to evaluate these strategies. Here we report on a model to simultaneously evaluate both of these treatment approaches. METHODS: Allogeneic clot was injected through the 6 F guide catheter after creating \u3e50% luminal stenosis of the common carotid arteries of New Zealand White rabbits. The stenosis was released after 1 h, allowing sufficient time for clot-vessel wall interaction. Occlusion was confirmed and each vessel was assigned to receive either balloon angioplasty alone, intra-arterial tissue plasminogen activator (tPA, Alteplase, Genentech, San Francisco, California, USA), tPA delivery through prototype balloon infusion wire (NIT Therapeutics, Pittsburgh, Pennsylvania, USA), partial stent deployment or partial stent deployment with locally delivered tPA. The negative control received no treatment. RESULTS: In vivo revascularization Thrombolysis in Cerebral Infarction (TICI) score revealed that the balloon infusion wire achieved a stable and higher revascularization score of TICI 2B, with a lower dose of tPA in comparison with other treatment strategies. All treatment strategies resulted in endothelial denudation and exposure of the internal elastic lamina. CONCLUSIONS: The proposed animal model permits reliable and consistent thromboembolic occlusion of the target vasculature and allows for an assessment of both pharmacologic and mechanical revascularization strategies for acute ischemic stroke