RESUMEN

The OSIRIS-REx Camera Suite (OCAMS) onboard the OSIRIS-REx spacecraft is used to study the shape and surface of the mission's target, asteroid (101955) Bennu, in support of the selection of a sampling site. We present calibration methods and results for the three OCAMS cameras-MapCam, PolyCam, and SamCam-using data from pre-flight and in-flight calibration campaigns. Pre-flight calibrations established a baseline for a variety of camera properties, including bias and dark behavior, flat fields, stray light, and radiometric calibration. In-flight activities updated these calibrations where possible, allowing us to confidently measure Bennu's surface. Accurate calibration is critical not only for establishing a global understanding of Bennu, but also for enabling analyses of potential sampling locations and for providing scientific context for the returned sample.

RESUMEN

OBJECTIVES: To analyse the biological effects of a 1920 nm endovenous laser (EVL) on extra-fascial great saphenous vein (GSV) in vitro. METHODS: A 10 cm length of a large tributary bypassing a hypoplastic segment of the GSV (sometimes called an "extra-fascial GSV") was obtained during routine varicose vein surgery. The length was treated in five sections with different LEEDs (0 (control), 20, 40, 60, and 80 J/cm) with a 1920 nm EVL at 4W power, in a novel in vitro treatment model. The biological effects were assessed by histological staining of the samples for haematoxylin and eosin (HE) and Martius Scarlet Blue (MSB), and by immunofluorescent detection of p-p53 and VCAM-1. RESULTS: Histological analysis showed significant structural damage at LEEDs above 60 J/cm, especially in the intima and media, with the treatment at 80 J/cm causing perforation of the vein wall. In addition, there was a significant increase in p-p53 expression in treated tissue at 60 and 80 J/cm. CONCLUSIONS: Using this ex vivo model, the results indicate that in vitro treatment with a 1920 nm EVL, at or above an LEED of 60 J/cm and 4 W power, causes significant vein wall cell death reaching deep into the media by a combination of direct thermal damage and apoptosis. A wavelength of 1920 nm appears to be effective for the endovenous ablation of truncal veins.

RESUMEN

OBJECTIVES: Endovenous thermal ablation (EVTA) of varicose veins was introduced in the late 1990s with radiofrequency ablation (RFA) using the VNUS Closure device. The results of the original VNUS Closure device for the abolition of truncal venous reflux at 15 years are reported. METHODS: A prospective audit of a group of patients treated with VNUS Closure 15 years previously was carried out, using clinical assessment and duplex ultrasound. A total of 189 patients were treated with VNUS Closure between March 1999 and December 2001 and were invited for clinical assessment (subjective and objective) and duplex ultrasonography (DUS) to assess treatment outcome and de novo disease progression. DUS outcome of the treated vein was graded: 1, complete success (complete atrophy); 2, partial success (> 1 patent section; none giving rise to recurrent varicose veins); 3, partial failure (≥ 1 patent sections giving rise to recurrent varicose veins); 4, complete failure. RESULTS: Fifty-eight patients (91 legs, 101 truncal veins) returned for follow-up DUS, giving a 31.5% response rate (many patients had moved or had died in the 15 years). Two truncal veins had been excluded following treatment elsewhere presumably for partial or complete failure. At a mean of 15.4 years post-procedure, 51 (56%) reported no varicose veins, 58 (100%) that they were pleased that they had the procedure and 57 (98%) that they would recommend the procedure. DUS showed 88% of patients achieved success with no clinical recurrence in the originally treated veins. De novo reflux was identified in 47 of 91 legs (51.6%), showing disease progression in veins that were originally competent. CONCLUSIONS: RFA with VNUS Closure achieved excellent long-term technical success in treating venous reflux in truncal veins 15 years post-procedure, demonstrated by DUS. This bodes well for the increased use of EVTA in treating truncal vein reflux.

Asunto(s)

RESUMEN

OBJECTIVE/BACKGROUND: Traditionally, sclerotherapy has been thought to work by the cytotoxic effect of the sclerosant upon the endothelium alone. However, studies have shown that sclerotherapy is more successful in smaller veins than in larger veins. This could be explained by the penetration of the sclerosant, or its effect, into the media. This study aimed to investigate intimal and medial damage profiles after sclerosant treatment. METHODS: Fresh human varicose veins were treated ex vivo with either 1% or 3% sodium tetradecyl sulphate (STS) for 1 or 10 minutes. The effect of the sclerosant on the vein wall was investigated by immunofluorescent labelling of transverse vein sections using markers for endothelium (CD31), smooth muscle (α-actin), apoptosis (p53) and inflammation (intercellular adhesion molecule-1 [ICAM-1]). Polidocanol (POL; 3%) treatment at 10 minutes was similarly investigated. RESULTS: Endothelial cell death was concentration- and time-dependent for STS but incomplete for both sclerosants. Time, but not concentration, significantly affected cell death (p > .001). A 40% and 30% maximum reduction was observed for STS and POL, respectively. Destruction of 20-30% of smooth muscle cells was found up to 250 µm from the lumen after 3% STS treatment for 10 minutes. POL treatment for 10 minutes showed inferior destruction of medial cells. Following STS treatment and 24-hour tissue culture, p53 and ICAM-1 were upregulated to a depth of around 300 µm. This effect was not observed with POL. CONCLUSION: Inflammatory and apoptotic markers show the same distribution as medial cell death, implying that sclerotherapy with STS works by inducing apoptosis in the vein wall rather than having an effect restricted to the endothelium. Incomplete loss of endothelial cells and penetration of the sclerosant effect up to 250 µm into the media suggest that medial damage is crucial to the success of sclerotherapy and may explain why it is less effective in larger veins.

Asunto(s)

RESUMEN

Porphyromonas gingivalis is a Gram-negative anaerobe and keystone periodontal pathogen. A mariner transposon insertion mutant library has recently been used to define 463 genes as putatively essential for the in vitro growth of P. gingivalis ATCC 33277 in planktonic culture (Library 1). We have independently generated a transposon insertion mutant library (Library 2) for the same P. gingivalis strain and herein compare genes that are putatively essential for in vitro growth in complex media, as defined by both libraries. In all, 281 genes (61%) identified by Library 1 were common to Library 2. Many of these common genes are involved in fundamentally important metabolic pathways, notably pyrimidine cycling as well as lipopolysaccharide, peptidoglycan, pantothenate and coenzyme A biosynthesis, and nicotinate and nicotinamide metabolism. Also in common are genes encoding heat-shock protein homologues, sigma factors, enzymes with proteolytic activity, and the majority of sec-related protein export genes. In addition to facilitating a better understanding of critical physiological processes, transposon-sequencing technology has the potential to identify novel strategies for the control of P. gingivalis infections. Those genes defined as essential by two independently generated TnSeq mutant libraries are likely to represent particularly attractive therapeutic targets.

Asunto(s)

RESUMEN

BACKGROUND: High levels of anxiety during surgery are associated with poorer post-surgical outcomes. This prospective, non-blinded randomized controlled trial aimed to compare the effectiveness of four intraoperative distraction interventions for anxiety and pain management during minimally invasive venous surgery under local anaesthetic. METHODS: 407 patients presenting with varicose veins at a private clinic, were randomized to one of four intraoperative distraction interventions or treatment as usual. All participants received endovenous thermoablation and/or phlebectomies of varicose veins. After losses to follow-up, 398 participants were entered into the analysis. Participants were randomly allocated to one of the following intraoperative distraction techniques: patient selected music (n = 85), patient selected DVD (n = 85), interaction with nurses (n = 81), touch (stress balls) (n = 80) or treatment as usual (TAU, n = 76). The state scale of the STAI, the Short-form McGill pain questionnaire and numeric rating scales were used to assess intraoperative pain and anxiety. RESULTS: Intraoperative anxiety ratings were significantly lower when participants interacted with nurses, used stress balls or watched a DVD during surgery compared to treatment as usual. Intraoperative pain ratings were significantly lower than treatment as usual when participants interacted with nurses or used stress balls during surgery. Patients' satisfaction was not significantly impacted by intraoperative distractions. CONCLUSIONS: The use of simple intraoperative distraction techniques, particularly interacting with nurses, using stress balls or watching a DVD during surgery conducted under local anaesthetic can significantly improve patients' experiences.

Asunto(s)

RESUMEN

OBJECTIVES: To assess the suitability of transvaginal duplex ultrasonography to identify pathological reflux in the ovarian and internal iliac veins in women. METHODS: A retrospective study of patients treated in 2011 and 2012 was performed in a specialised vein clinic. Diagnostic transvaginal duplex ultrasonography in women presenting with symptoms or signs of pelvic vein reflux were compared with the outcomes of treatment from pelvic vein embolisation. A repeat transvaginal duplex ultrasonography was performed 6 weeks later by a blinded observer and any residual reflux was identified. RESULTS: Results from 100 sequential patients were analysed. Mean age 44.2 years (32-69) with mode average parity of 3 (0-5 deliveries). Pre-treatment, 289/400 veins were refluxing (ovarian - 29 right, 81 left; internal iliac - 93 right, 86 left). Coil embolisation was successful in 86/100 patients and failed partially in 14/100 - 5 due to failure to cannulate the target vein. One false-positive diagnosis was made. CONCLUSION: Currently there is no accepted gold standard for pelvic vein incompetence. Comparing transvaginal duplex ultrasonography with the outcome from selectively treating the veins identified as having pathological reflux with coil embolisation, there were no false-negative diagnoses and only one false-positive. This study suggests that transvaginal duplex ultrasonography could be the gold standard in assessing pelvic vein reflux.

Asunto(s)

RESUMEN

BACKGROUND: There are various methods advocated for the treatment of verruca plantaris. However, many verrucas do not respond to simple treatment. OBJECTIVE: This study presents our results using Nd: YAG laser ablation therapy for such recalcitrant cases. METHODS: We performed a retrospective audit by sending a questionnaire to all patients with recalcitrant verrucas who had been treated with Nd:YAG laser ablation over the previous 12 months. The questionnaire asked whether treatment had been successful, successful but new lesions had emerged, partially successful with improvement or unsuccessful. A Fontana Nd:YAG laser was used at the following specifications; long pulsed mode with pulse width 25 ms, frequency 1.0 Hz; fluence 240 J/cm(2) and spot size 2 mm. Some patients requested local anaesthesia and had direct infiltration with 0.5% plain lidocaine. RESULTS: Fifty-three of the original 87 patients responded (60.9% response rate) with a male to female ratio of 24:29, mean age of 47 years and an age range between 22-72. Thirty-seven patients reported complete success post treatment (69.8%) and a further five reported improvement. The remaining 11 felt their treatment was unsuccessful. The cure rate was 81.8% in unilateral single cases, 68.1% in unilateral multiple cases and 65% in bilateral cases. Ten patients requested sublesional lidocaine injections of which 4 had skin breakdown after Nd: YAG ablation. CONCLUSION: Nd:YAG laser ablation is effective in the treatment of recalcitrant verruca plantaris. However, we caution against the use of direct local anaesthesia infiltration before laser treatment.

Asunto(s)

RESUMEN

OBJECTIVES: To determine the prevalence of haemorrhoids in women with pelvic vein reflux, identify which pelvic veins are associated with haemorrhoids and assess if extent of pelvic vein reflux influences the prevalence of haemorrhoids. METHODS: Females presenting with leg varicose veins undergo duplex ultrasonography to assess all sources of venous reflux. Those with significant reflux arising from the pelvis are offered transvaginal duplex ultrasound (TVS) to evaluate reflux in the ovarian veins and internal Iliac veins and associated pelvic varices in the adnexa, vulvar/labial veins and haemorrhoids. Patterns and severity of reflux were evaluated. RESULTS: Between January 2010 and December 2012, 419 female patients with leg or vulvar varicose vein patterns arising from the pelvis underwent TVS. Haemorrhoids were identified on TVS via direct tributaries from the internal Iliac veins in 152/419 patients (36.3%) and absent in 267/419 (63.7%). The prevalence of the condition increased with the number of pelvic trunks involved. CONCLUSION: There is a strong association between haemorrhoids and internal Iliac vein reflux. Untreated reflux may be a cause of subsequent symptomatic haemorrhoids. Treatment with methods proven to work in conditions caused by pelvic vein incompetence, such as pelvic vein embolisation and foam sclerotherapy, could be considered.

Asunto(s)

RESUMEN

OBJECTIVES: Previous research into pelvic venous reflux has suggested that the size of the ovarian veins indicates the presence or absence of reflux. It is already known that vessel diameter is not an indicator of reflux in the great saphenous vein. However, to this day, physicians still use vein size to plan treatment of refluxing ovarian veins. The authors aimed to investigate whether or not vessel diameter can be used as an indicator of reflux in the ovarian veins. METHODS: Nineteen female patients (mean 40.2 years, range 29-60) presenting to a specialist vein unit with leg varicose veins underwent duplex ultrasonography (DUS). All were found to have a significant pelvic contribution to their leg reflux on transvaginal duplex ultrasonography (TVS) and were referred to an interventional radiologist for treatment by transjugular coil embolization. During the procedure, the diameter of the ovarian veins was measured using digital subtraction venography. RESULTS: Thirty-four ovarian veins were measured (17 right, 17 left) and of these 18 were found to be non-refluxing while 16 displayed reflux. The mean diameter of the non-refluxing veins was 7.2 mm (range 3-13 mm)and that of the refluxing veins was 8.5 mm (range 4-13 mm). This difference was found to be insignificant at a 95% confidence level (Student t test, p = .204). CONCLUSIONS: There is no significant difference between the diameters of competent and refluxing ovarian veins and, as such, techniques that measure vein diameter may not be suitable for the diagnosis of venous reflux in the ovarian veins.

Asunto(s)

Asunto(s)

RESUMEN

OBJECTIVES: This is a retrospective study over 12 years reporting the healing rates of leg ulcers at a specialist vein unit. All patients presented with active chronic venous leg ulcers (clinical,aetiological, anatomical and pathological elements [CEAP]: C6) and had previously been advised elsewhere that their ulcers were amenable to conservative measures only. METHOD: Seventy-two patients (84 limbs) were treated between March 1999 and June 2011. Patients were contacted in August 2011 by questionnaire and telephone. Of 72 patients,two were deceased and two had moved location at follow-up, so were not contactable. Fifty patients replied and 18 did not (response rate 74%), representing a mean follow-uptime of 3.1 years. RESULTS: Ulcer healing occurred in 85% (44 of 52 limbs) of which 52% (27) limbs were no longer confined to compression. Clinical improvement was achieved in 98% of limbs. CONCLUSIONS: This study shows that a significant proportion of ulcers currently managed conservatively can be healed by surgical intervention.

Asunto(s)

Asunto(s)

RESUMEN

INTRODUCTION: Deep vein thrombosis (DVT) after varicose vein surgery is well recognised. Less well documented is endovenous heat-induced thrombosis (EHIT), thrombus extension into a deep vein after superficial venous thermoablation. We examined the rates of DVT in our unit after radiofrequency (RFA) and endovenous laser ablation (EVLA) with specific attention to thrombus type. METHOD: Retrospective analysis of all cases of RFA under general anaesthesia and EVLA under local anaesthesia was performed. Cases of DVT were identified from the unit database and analysed for procedural details. RESULTS: In total, 2470 cases of RFA and 350 of EVLA were performed. Post-RFA, DVT was identified in 17 limbs (0.7%); 4 were EHIT (0.2%). Concomitant small saphenous vein (SSV) ligation and stripping was a risk factor for calf-DVT (OR 3.4, 95%CI 1.2-9.7, P=0.036), possibly due to an older patient group with more severe disease. Post-EVLA, 4 DVTs were identified (1%), of which 3 were EHIT (0.9%). CONCLUSION: The DVT rate including EHIT was similar in patients treated with RFA and EVLA and was low. Routine post-operative duplex ultrasound scanning is recommended until the significance of EHIT is better understood, in accordance with consensus guidelines. DVT rates for both techniques compare favourably with those published for saphenous vein stripping.

Asunto(s)

RESUMEN

OBJECTIVES: Early success treating incompetent perforator veins (IPVs) with radiofrequency ablation (RFA) and the trend to move varicose vein surgery into a walk-in walk-out service led to the design of a specific device enabling RFA of IPVs using local anaesthesia (ClosureRFS stylet). Our aim was to assess one-year outcomes of a clinical series of patients undergoing treatment with this device. Truncal reflux, where present, was treated initially, and RFA of IPVs was performed as a secondary procedure. METHOD: Duplex ultrasound examinations were performed and the presence of IPVs documented. Results were compared with preoperative scans. IPVs were classified as closed, not closed/reopened or de novo. RESULTS: Of the 75 patients invited for follow-up, 53 attended at a median time of 14 months (range 11-25). Sixty-seven limbs were analysed (M:F 1:2.1, median age 62, range 25-81). Of the 124 treated IPVs, 101 were closed (82%). Clinical, aetiological, anatomical and pathological clinical score was improved in 49.3% limbs. IPV closure was reduced in patients with recurrent varicose veins compared with primary varicose veins (72.3% versus 87%, P = 0.056). CONCLUSION: These results demonstrate the radiofrequency stylet device to be an effective treatment for IPVs.

Asunto(s)

RESUMEN

OBJECTIVES: Mounting evidence suggests that pelvic vein reflux is an important contributing factor to recurrent varicose veins. We compared the incidence in our specialist private unit (Unit A) with that of a District General Hospital (Unit B). METHODS: Results of all female patient lower limb duplex ultrasound (LLDUS) and transvaginal pelvic ultrasound (TVUS) scans performed over a one-year period were retrospectively reviewed. Patients with refluxing veins emanating from the abdomen or pelvis on LLDUS (non-saphenous reflux) routinely proceeded to TVUS in Unit A. RESULTS: In Unit A, non-saphenous reflux on LLDUS was present in 90-462 female patients (19.5%). In 81.1% of these, TVUS confirmed reflux in truncal pelvic veins (incidence 15.8%). In Unit B, non-saphenous reflux was present in 60-279 female patients (21.5%). CONCLUSION: One in five women presenting with varicose veins have reflux of non-saphenous origin. This is the case in specialist and non-specialist units. One in six has associated pelvic vein reflux.

Asunto(s)