High sensitivity 10Gb/s Si photonic receiver based on a low-voltage waveguide-coupled Ge avalanche photodetector.

We demonstrate low-voltage germanium waveguide avalanche photodetectors (APDs) with a gain × bandwidth product above 100GHz. A photonic receiver based on such a Ge APD, including a 0.13µm SiGe BiCMOS low-noise trans-impedance amplifier and a limiting amplifier, is realized. A 5.8dB sensitivity improvement is demonstrated at -5.9V bias at an avalanche gain of 6 through bit error ratio measurements. The absolute sensitivity in avalanche mode is -23.4dBm and -24.4dBm at a bit error ratio of 1 × 10(-12) and 1 × 10(-9) respectively.

Spontaneous rupture of an aneurysm of the right subclavian artery as a first presentation of Ehlers Danlos syndrome in a 15-year old boy.

We report a case of a spontaneous rupture of a right subclavian aneurysm in a 15 year-old patient. This ruptured aneurysm was successfully treated in an endovascular manner by placing a covered stent-graft in the right subclavian artery via right brachial access. Subsequent work-up by skin biopsy and fibroblast culture and by DNA-screening revealed the diagnosis of Ehlers Danlos type IV. Meanwhile, the patient developed twice a spontaneous pneumothorax, treated with thoracoscopic pleurodesis. This article provides a clear overview of the clinical and genetic characteristics of a case of Ehlers Danlos type IV and illustrates the importance of avoiding surgery in patients with connective tissue disease because of the high risk of perioperative complications.

Dysphagia lusoria. Indications and surgical approaches for non-aneurysmatic aberrant right subclavian artery.

Non-aneurysmatic aberrant right subclavian artery is a rare cause of dysphagia. We report a case of a 65-year-old female patient having a symptomatic lusorian artery. We reviewed literature as for indications and operative techniques for type I lusorian arteries. Different types of surgical approaches have been reported but there is no consensus to date. We performed a minimally invasive sternotomy with right cervicotomy. This surgical approach maximized our visibility resulting in a safe dissection, resection and reinsertion of the aberrant right subclavian artery. Postoperative morbidity was low.

Direct discharge of patients with simple stable musculoskeletal injuries as an alternative to routine follow-up: a systematic review of the current literature.

PURPOSE: There is growing evidence that patients with certain simple stable musculoskeletal injuries can be discharged directly from the Emergency Department (ED), without compromising patient outcome and experience. This study aims to review the literature on the effects of direct discharge (DD) of simple stable musculoskeletal injuries, regarding healthcare utilization, costs, patient outcome and experience. METHODS: A systematic review was performed in Medline, Embase, CINAHL, Cochrane Library and Web of Science using PRISMA guidelines. Comparative and non-comparative studies on DD of simple stable musculoskeletal injuries from the ED in an adult/paediatric/mixed population were included if reporting ≥ 1 of: (1) logistic outcomes: DD rate (proportion of patients discharged directly); number of follow-up appointments; DD return rate; (2) costs; (3) patient outcomes/experiences: functional outcome; treatment satisfaction; adverse outcomes; other. RESULTS: Twenty-six studies were included (92% conducted in the UK). Seven studies (27%) assessed functional outcome, nine (35%) treatment satisfaction, and ten (38%) adverse outcomes. A large proportion of studies defined DD eligibility criteria as injuries being minor/simple/stable, without further detail. ED DD rate was 26.7-59.5%. Mean number of follow-up appointments was 1.00-2.08 pre-DD, vs. 0.00-0.33 post-DD. Return rate was 0.0-19.4%. Costs per patient were reduced by €69-€210 (ranging from - 38.0 to - 96.6%) post-DD. Functional outcome and treatment satisfaction levels were 'equal' or 'better' (comparative studies), and 'high' (non-comparative studies), post-DD. Adverse outcomes were low and comparable. CONCLUSIONS: This systematic review supports the idea that DD of simple stable musculoskeletal injuries from the ED provides an opportunity to reduce healthcare utilization and costs without compromising patient outcomes/experiences. To improve comparability and facilitate implementation/external validation of DD, future studies should provide detailed DD eligibility criteria, and use a standard set of outcomes. Systematic review registration number: 120779, date of first registration: 12/02/2019.

Drug-eluting stents below the knee.

The fear that early thrombosis and late luminal loss due to intimal hyperplasia formation potentially leads to insufficient long-term patency rates can explain the reluctance on implanting stents in small diameter below-the-knee (BTK) arteries. Drug-eluting stent (DES) technology was developed to prevent early thrombosis and late luminal loss to potentially improve long-term patency rates. Currently, the first level 1 evidence from prospective, randomized, controlled DESTINY and ACHILLES studies indicate that the implantation of DES in short lesion lenghts in the infrapopliteal vasculature leads to favorable outcomes with high primary patency rates. This makes that primary DES placement can be recommended as treatment strategy in short BTK-lesions.

Variants of the BMP15 gene in a cohort of patients with premature ovarian failure.

BACKGROUND: Bone morphogenetic protein 15 (BMP15) is an oocyte-derived growth factor acting as a major player in follicle differentiation in mammals. Mutations in the BMP15 gene, some of which lead to defective secretion of bioactive dimers, have been associated with premature ovarian failure (POF) in humans. METHODS: Fifty patients diagnosed with POF with a normal karyotype were included in the study. After DNA extraction and amplification by PCR, the entire coding sequence and intron-exon junctions of BMP15 gene were analysed in the cohort of POF patients and in a control group of 214 patients. RESULTS: Nine variants of the BMP15 gene including six missense substitutions and one insertion of three nucleotides were identified in the POF group. Three of them were previously described as single nucleotide polymorphisms and were also found in the control group. Two variants (H81R and G199R) have not been previously described and were not identified among controls but were not predicted to be deleterious. One variant (A180T) was identified among two POF cases, and also in two controls. One variant (F194S), predicted as potentially deleterious, was identified for the first time in a POF patient but also identified in one control. One variant (L148P), potentially deleterious, previously reported in POF patients, was identified for the first time among controls. The variant 788insTCT, previously identified among POF patients, probably has a low biological impact as it was also found in control patients and is a common polymorphism in sub-Saharan African populations. CONCLUSIONS: Various missense variants of the BMP15 gene were identified among patients with POF. For most variants, the impact of the amino-acid substitution on the protein structure and function was predicted to be low. The two variants predicted as potentially deleterious were also identified among controls and could be considered as rare polymorphisms. Although some of these variants could contribute to the development of POF in a complex manner, the demonstration of their role in the pathogenesis of POF requires additional functional studies.

Prevention and treatment of in-stent restenosis.

In-stent restenosis has always been an important issue, since the launch of the first stents on the market. The occurrence of in-stent restenosis (ISR) is due to two main reasons. First, the presence of stent fractures significantly influences restenosis rates. Second, the continuous interaction between the permanently implanted artificial material and the vessel tissue, leads to physical irritation, long-term endothelial dysfunction, or chronic inflammatory reactions. In the Literature only very limited data on ISR treatment in the peripheral arteries are available. There are no peer-reviewed publications or studies with in-depth follow-up on this specific indication. The underlying reason for this probably being that currently available treatments do not yield satisfactory results. However, the continuing search for better solutions and the technological evolution lead to the introduction of the Viabahn with PROPATEN coating, DES and DCB, which may result in the first promising treatment options for ISR.

Are drug-eluting stents the future of SFA treatment?

Drug-eluting stent (DES) technology was developed to prevent early thrombosis and late luminal loss to potentially improve long-term patency rates. Although favorable DES results have recently become available with the Zilver PTX and STRIDES studies, the high price of DES is a major drawback for this technology to become the golden standard for peripheral endovascular therapy in de novo femoro-popliteal (FP) lesions. Nevertheless, DES has the potential to make the difference and to establish itself as an important treatment option in patients presenting with TASC C&D FP lesions who are at high-risk for surgery and for the treatment of in-stent restenosis, where until now, no valuable treatment option has proven to be beneficial.

Are bio-absorbable stents the future of SFA treatment?

Several limitations inherent to the implantation of a metallic device, such as the occurrence of in-stent re-stenosis, in an arterial lumen intuitively explain the interest for developing bio-absorbable stents. Two main types of bio-absorbable stents currently exist: polymer stents and metallic stents. To date, no studies with bio-absorbable stents have been conducted in the superficial femoral artery (SFA). Because of their strut thickness and lack of radial force, polymer stents are no good candidates for endovascular use. Absorbable metal stents (AMS) do have the potential to perform well for artery treatment, although current evidence from in-human coronary and infrapopliteal studies yield unsatisfactory results. Drastic technological improvements are mandatory before AMS can be considered for every day practice. Yet, it is our belief that further development of other metal and non-metal bio-absorbable stents, with or without drug-coating, may lead to the creation of the ultimate SFA stent.

Endovascular management of acute limb ischemia.

Acute limb ischemia (ALI) refers to a rapid worsening of limb perfusion resulting in rest pain, ischemic ulcers or gangrene. With an estimated incidence of 140 million/year, ALI is serious limb-threatening and life-threatening medical emergency demanding prompt action. Three prospective, randomized clinical trials provide data on trombolytic therapy versus surgical intervention in patients with acute lower extremity ischemia. Although they did not give us the final answer, satisfactory results are reported for percutaneous thrombolysis compared with surgery. Moreover, they suggest an important advantage of thrombolysis in acute bypass graft occlusions. Therefore, we believe thrombolytic therapy should be a part of the vascular surgeon's armamentarium to safely and successfully treat ALI patients.

The role of carotid artery stenting for recent cerebral ischemia.

Patients with cerebral ischemia as a result of acute cervical internal carotid artery occlusion are generally considered to have a poor prognosis. Despite maximal medical treatment, a better treatment for patients with acute ischemic stroke who present with serious neurologic symptoms on admission or continue to deteriorate neurologically due to a total occlusion, a dissection or a high-grade stenosis of the internal carotid artery is required. An effective intervention to improve their neurologic symptoms and clinical outcome has not yet been established and represents a challenging and complex problem. Treatment of acute symptomatic occlusion of the cervical internal carotid artery includes intravenous administration of thrombolytic agent, carotid endarterectomy and an interventional approach (intra-arterial administration of thrombolytic agent, transluminal angioplasty with or without stenting). The endovascular interventional approach is becoming a part of the stroke therapy armamentarium for intracranial occlusion. It may also now be considered in select patients with acute internal carotid artery occlusion. Stenting and angioplasty for acute internal carotid artery occlusion appears to be feasible, safe and may be associated with early neurological improvement. The encouraging preliminary results await confirmation from prospective, randomized studies.

Other endovascular methods of treating the diabetic foot.

Critical limb ischemia (CLI) is an endstage manifestation of peripheral artery disease (PAD) and typically describes patients with ischemic rest pain (Rutherford Category 4), or patients with ischemic skin lesions, either ulcers or gangrene (Rutherford Category 5-6). CLI due to infrapopliteal lesions is often not a good indication for infrageniculate bypass surgery placement, due to the presence of prohibitive comorbidities, inadequate conduit, and lack of suitable distal targets for revascularization. Therefore, CLI patients due to blockage of below-the-knee arteries are in benefit of the endovascular approach. Infrapopliteal PTA became feasible with the introduction of low-profile peripheral balloon systems and the use of coronary balloons. Stent implantation, however, is generally reserved for cases with a suboptimal outcome after PTA (i.e. >50% residual stenosis, flow-limiting dissection). Because of the fear that early thrombosis and late luminal loss due to intimal hyperplasia formation will potentially lead to insufficient long-term patency rates, efforts to extend the range of endovascular approaches to CLI are presently focused on. Cryoplasty, scoring balloon angioplasty, excimer laser therapy and atherectomy using different types of atherectomy devices have been introduced. The current article provides an overview of the endovascular treatment strategies for infrapopliteal lesions in patients with CLI.

Update management below knee intervention.

The application of percutaneous techniques for the treatment of peripheral arterial occlusive disease (PAOD) has gained widespread interest over the last decade. Together with the development of new endovascular tools and with an increasing operator experience, the minimal invasive percutaneous therapy became first line therapy at many institutions. Patients with critical limb ischemia (CLI) due to infrapopliteal lesions are often no good candidates infra-geniculate bypass surgery (IBS), as they often present with prohibitive comorbidities, inadequate conduit, and lack of suitable distal targets for revascularization. Therefore, CLI patients due to blockage of below-the-knee (BTK) arteries are in benefit of the endovascular approach: it offers the advantages of local anesthesia, potentially reduced costs (even anticipating the need for reintervention in many patients), shorter hospital stays The current article provides an overview of the diagnosis and endovascular treatment strategies for infrapopliteal lesions in patients with CLI and gives recommendations for future infrapopliteal device technology advancements.

Treatment of a left common iliac aneurysm with endovascular Powerlink stentgraft in a patient with an occlusion of a left common iliac stent.

Isolated iliac aneurysms are uncommon and account for only 2% of all abdominal aneurysms. Typically, patients presenting with this pathology are operated on surgically. In our patient, however, surgery could have been an option but the patient had undergone a laparotomy more than 50 years earlier because of a gun-shot wound, so we preferred an endovascular repair. Furthermore, regular endovascular repair with a straight tube stentgraft was impossible due to the absence of a proximal neck. Consequently, we opted for placing a bifurcated stentgraft to exclude the iliac aneurysm.

What practical factors guide the choice of stent and protection device during carotid angioplasty?

The importance of angioplasty and stenting in the treatment of carotid artery disease cannot be underestimated. Successful carotid stenting does not only depend of the operator's skills and experience, but also an adequate selection of cerebral protection devices and carotid stents can help avoiding neurological complications. A broad spectrum of carotid devices is currently on the market and since all have their assets and downsides, it is virtually impossible to acclaim one specific device as being the best. The individual characteristics of each specific protection system or stent may make it an attractive choice in one circumstance, but render it a less desirable option in others situations. The applicability depends primarily on the arterial anatomy and the specific details of the lesion being treated. But certainly, personal preferences and familiarity with a specific device may legitimately influence the decision to choose one over another.

Present and future of endovascular SFA treatment: stents, stent-grafts, drug coated balloons and drug coated stents.

The current evolution towards treating more complex femoropopliteal lesions as seen in the renewed TASC II recommendations clearly reflects the continuous evolutions in femoropopliteal stent design. Recent stent design improvements focus on decreasing stent fractures rates which can negatively impact patency rates. By rearranging strut alignment towards helical connecting bridges or full helical stent designs, stent designers have successfully improved the fracture resistance of their stents. The superior fracture resistance of the latest stent generation in combination with the production of long nitinol stents of up to 20 cm in length allow that more difficult and complex lesions can be treated endovascularly. The continuous perfection of nitinol stent platforms followed by the transfer of coronary technologies (e.g. active coatings) towards peripheral devices might broaden the indications for the minimal invasive strategy towards TransAtlantic Inter-Society Consensus (TASC) II C&D lesions.

Nitinol stenting for treatment of ''below-the-knee'' critical limb ischemia: 1-year angiographic outcome after Xpert stent implantation.

AIM: We investigated the efficacy of Xpert (Abbott Vascular Devices) nitinol stents for the treatment of infrapopliteal lesions in patients with critical limb ischemia (CLI). METHODS: Between May and October 2005, 47 CLI patients (35 men, mean age 73 years) received 67 Xpert stents for the treatment of 58 infrapopliteal lesions in 51 limbs; 43 patients (84.3%) were classified in Rutherford Category 4 and 8 (15.7%) in Category 5. Clinical examination and quantitative vascular analysis (QVA) were performed before and after the intervention and at 12-months follow-up. The primary endpoint was defined as 1-year angiographic binary restenosis rate (>50% stenosis on QVA); the secondary endpoints were 1-year primary patency and limb salvage rate. RESULTS: QVA after 1 year showed a binary restenosis rate of 20.45%. Kaplan-Meier analysis revealed 1-year primary patency and limb salvage rates of 76.3% and 95.9%, respectively. The limb salvage rate was significantly better in patients with proximal below-the-knee (BTK) than in those with mid-section or distal lesions (100% vs 81.8%; P=0.0071). CONCLUSION: Our results suggest that treatment with nitinol Xpert stents in CLI patients is effective and yields satisfactory angiographic and clinical outcome.

Flemish experience using the Advanta V12 stent-graft for the treatment of iliac artery occlusive disease.

AIM: The aim of this study was to evaluate the technical feasibility and safety of implanting a polytetrafluoroethylene (PTFE) covered balloon expandable stent to treat iliac artery stenoses and occlusions. Additionally, the primary patency and clinical and hemodynamic efficacy at 1 year were analysed. METHODS: This nonrandomized, prospective study involved patients with claudication and iliac artery occlusive disease at 2 participating centres. Patients with suitable lesions determined by clinical examination, ankle-brachial indices (ABIs), colour-flow duplex ultrasound (CFDU), magnetic resonance angiogram (MRA) and confirmed with biplanar digital subtraction angiography (DSA) were treated with PTFE-covered stainless steel stents. Procedural and 30-day periprocedural complications were recorded prospectively. According to in-hospital standards, follow-up with clinical ischemia category determination, ABI and CFDU was performed at 1, 6 and 12 months to determine treatment efficacy and primary limb patency. RESULTS: In total, 91 limbs were treated in 65 patients (51 male; mean age 65 years). Stent-graft deployment was successful in 91 (100%) limbs. There were no limbs with residual stenosis >30%. There were no procedural or 30-day complications. The clinical ischemia category distribution improved significantly at 1, 6 and 12 months. The mean ABI rose significantly from 0.59 before treatment to 0.98, 0.98 and 0.99 at 1, 6 and 12 months after the procedure. Primary limb patency at 1-year was 91.1% CONCLUSIONS: Implantation of Advanta V12 PTFE-covered stent for iliac occlusive disease shows to be safe and feasible with excellent clinical results at 1 year in the investigated patient cohort.

Are there predictive risk factors for complications after carotid artery stenting?

AIM: The aim of this study was to identify predictive risk factors for complications during and after carotid artery stenting (CAS). METHODS: A multivariate analysis was performed on the databases of 4 European high-volume centers regarding risk factor distribution between patients presenting with or without neurological complications 30 days after CAS. The cumulative 30-day neurological complication rate (death, major stroke, minor stroke and transient ischemic attack) was 2.8% in the total examined cohort of 3 179 consecutive CAS procedures. The following risk factors were taken into consideration for statistical analysis: age, symptomatic, male gender, nicotine abuse, hypertension, hypercholesterolemia, polyvascular disease, diabetes, restenosis after carotid endarterectomy (CEA)/CAS, calcified internal carotid artery. RESULTS: Symptomatic (P=0.02) or hypercholesterolemic (P=0.02) patients are at significantly increased risk for neurological events 30 days after CAS. Asymptomatic women and men without hypercholesterolemia have the lowest risk on any 30-day neurological complications after CAS. CONCLUSIONS: CAS is a safe technique in experienced hands. Preprocedural neurological complaints and hypercholesterolemia can be defined as predisposing factors for 30-day neurological complications after CAS.