Clinical findings are not helpful in detecting lentigo maligna melanoma in patients with biopsy-proven lentigo maligna.

BACKGROUND: Lentigo maligna (LM) based on biopsy material might be lentigo maligna melanoma (LMM) after excision. OBJECTIVES: Investigate whether clinical and dermoscopic mapping increases the detection rate of LMM when investigating staged excision specimens of biopsy proven LM. METHODS: Patients with biopsy-proven LM planned for staged excision were included. Using clinical inspection and dermoscopy, spots suspicious for LMM were marked. After the excision, needles were placed at the marked spots. Histological examination using vertical sections was done at the needles followed by the standard amount of vertical sections. RESULTS: In 28 of the 58 biopsy-proven LM, there was clinical suspicion of LMM, only 3 of these 28 cases were upgraded into LMM. These three cases showed LMM in other sections, whereas only 1 case showed LMM around the needle. Within the group without clinical suspicion of LMM, 2 cases were LMM. Biopsy-proven LM were in fact LMM in 8.6% of the cases and were found without the clinical guidance of the dermatologist. CONCLUSIONS: 8.6% of the biopsy-proven LM were LMM after complete histological examination. In this study, the dermatologist was not able to increase the detection rate of LMM by using clinical and dermoscopic mapping.

Randomized clinical trial of endovenous laser ablation versus direct and indirect radiofrequency ablation for the treatment of great saphenous varicose veins.

BACKGROUND: The current treatment strategy for many patients with varicose veins is endovenous thermal ablation. The most common forms of this are endovenous laser ablation (EVLA) and radiofrequency ablation (RFA). However, at present there is no clear consensus on which of these treatments is superior. The objective of this study was to compare EVLA with two forms of RFA: direct RFA (dRFA; radiofrequency-induced thermotherapy) and indirect RFA (iRFA; VNUS ClosureFast™). METHODS: Patients with symptomatic great saphenous vein (GSV) incompetence were randomized to receive EVLA, dRFA or iRFA. Patients were followed up at 2 weeks, 6 and 12 months. The primary outcome was GSV occlusion rate. Secondary outcomes included Venous Clinical Severity Score (VCSS), Aberdeen Varicose Vein Questionnaire (AVVQ) score and adverse events. RESULTS: Some 450 patients received the allocated treatment (EVLA, 148; dRFA, 152; iRFA, 150). The intention-to-treat analysis showed occlusion rates of 75·0 (95 per cent c.i. 68·0 to 82·0), 59·9 (52·1 to 67·7) and 81·3 (75·1 to 87·6) per cent respectively after 1 year (P = 0·007 for EVLA versus dRFA, P < 0·001 for dRFA versus iRFA, P = 0·208 for EVLA versus iRFA). VCSS improved significantly for all treatments with no significant differences between them. AVVQ scores also improved significantly for all treatments, but iRFA had significantly better scores than dRFA at 12 months. Significantly more adverse events were reported after treatment with EVLA (103) than after dRFA (61) and iRFA (65), especially more pain. CONCLUSION: Primary GSV occlusion rates were better after iRFA and EVLA than dRFA. All three interventions were effective in improving the clinical severity of varicose veins at 1 year.

Substitution of low-risk skin cancer hospital care towards primary care: A qualitative study on views of general practitioners and dermatologists.

BACKGROUND: Rising healthcare expenditures places the potential for substitution of hospital care towards primary care high on the political agenda. As low-risk basal cell carcinoma (BCC) care is one of the potential targets for substitution of hospital care towards primary care the objective of this study is to gain insight in the views of healthcare professionals regarding substitution of skin cancer care, and to identify perceived barriers and potential strategies to facilitate substitution. METHODS: A qualitative study was conducted consisting of 40 interviews with dermatologists and GPs and three focus groups with 18 selected GPs with noted willingness regarding substitution of skin cancer care. The interviews and focus groups focused on general views, perceived barriers and potential strategies to facilitate substitution of skin cancer care, using predefined topic lists. All sessions were audio-taped, transcribed verbatim and analyzed using the program AtlasTi. RESULTS: GPs were generally positive regarding substitution of skin care whereas dermatologists expressed more concerns. Lack of trust in GPs to adequately perform skin cancer care and a preference of patients for dermatologists are reported as barriers by dermatologists. The main barriers reported by GPs were a lack of confidence in own skills to perform skin cancer care, a lack of trust from both patients and dermatologists and limited time and financial compensation. Facilitating strategies suggested by both groups mainly focused on improving GPs' education and improving the collaboration between primary and secondary care. GPs additionally suggested efforts from dermatologists to increase their own and patients' trust in GPs, and time and financial compensation. The selected group of GPs suggested practical solutions to facilitate substitution focusing on changes in organizational structure including horizontal referring, outreach models and practice size reduction. CONCLUSIONS: GPs and, to lesser extent, dermatologists are positive regarding substitution of low-risk BCC care, though report substantial barriers that need to be addressed before substitution can be further implemented. Aside from essential strategies such as improving GPs' skin cancer education and time and financial compensation, rearranging the organizational structure in primary care and between primary and secondary care may facilitate effective and safe substitution of low-risk BCC care.

Recurrence rates of cutaneous squamous cell carcinoma of the head and neck after Mohs micrographic surgery vs. standard excision: a retrospective cohort study.

BACKGROUND: Recurrent cutaneous squamous cell carcinoma (cSCC) has been associated with an increased risk of local functional and aesthetic comorbidity, metastasis and mortality. OBJECTIVES: To compare the risk of recurrence between Mohs micrographic surgery (MMS) and standard excision for cSCC of the head and neck. METHODS: This was a retrospective cohort study of all patients with a cSCC treated with MMS or standard excision at the departments of dermatology of a secondary or tertiary care hospital in the Netherlands between 2003 and 2012. To detect all recurrences, patients were linked to the Dutch pathology registry. To compare the risk of recurrence between MMS and standard excision, hazard ratios (HRs) were used adjusted for clinical tumour size > 2 cm and deep tumour invasion. RESULTS: A total of 579 patients with 672 cSCCs were included: 380 cSCCs were treated with MMS and 292 with standard excision. The risk of recurrence was 8% (22 of 292) after standard excision during a median follow-up of 5·7 years [interquartile range (IQR) 3·5-7·8], which was higher than the 3% (12 of 380) after MMS during a median follow-up of 4·9 years (IQR 2·3-6·0). The cumulative incidence of recurrence was higher for standard excision than for MMS during the entire follow-up period of 8·6 years. Carcinomas treated with MMS were at a three times lower risk of recurrence than those treated with standard excision when adjusted for tumour size and deep tumour invasion (adjusted HR 0·31, 95% confidence interval 0·12-0·66). CONCLUSIONS: MMS might be superior to standard excision for cSCCs of the head and neck because of a lower rate of recurrence.

Recurrence of periocular basal cell carcinoma and squamous cell carcinoma after Mohs micrographic surgery: a retrospective cohort study.

BACKGROUND: Despite the widespread use of Mohs micrographic surgery (MMS) for periocular basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) - together called keratinocyte carcinoma (KC) - follow-up data regarding recurrences are limited. OBJECTIVES: To investigate the recurrence rate for periocular KCs after MMS and to describe our experience with interdisciplinary collaborations. METHODS: Patients with periocular KCs treated with MMS between 2006 and 2016 in a tertiary MMS referral hospital were included in this retrospective cohort study. Descriptive statistics were used to describe the MMS procedure-related characteristics. Using follow-up data from the electronic patient records and linkage with the Dutch nationwide network and registry of histopathology and cytopathology on 30 June 2017, the recurrence rate was evaluated and calculated using a cumulative incidence curve. RESULTS: In total, 683 (93·7%) periocular BCCs and 46 (6·3%) SCCs were treated with MMS. Three-quarters (n = 549) were primary tumours and the majority were located at the medial canthus or lower eyelid (n = 649, 89·0%). In 505 MMS procedures (69·3%) an oculoplastic surgeon participated, and in 63 patients (8·6%) a plastic surgeon performed the reconstruction. After a median follow-up of 46 months the recurrence rate was 3·0%, based on 22 recurrences (20 BCCs and two SCCs). CONCLUSIONS: MMS is an excellent treatment option for periocular KCs, with a low recurrence rate. Due to this specific anatomical location an interdisciplinary approach should pre-eminently be considered.

Towards an individualized management strategy for patients with chronic venous disease: Results of a Delphi consensus.

Objective To obtain consensus on management criteria for symptomatic patients with chronic venous disease (CVD; C2-C6) and superficial venous reflux. Method We used a Delphi method by means of 36 statements sent by email to experts in the field of phlebology across the world over the course of three rounds. The statements addressed criteria for different venous treatments in patients with different characteristics (e.g. extensive comorbidities, morbid obesity and peripheral arterial disease). If at least 70% of the ratings for a specific statement were between 6 and 9 (agreement) or between 1 and 3 (disagreement), experts' consensus was reached. Results Twenty-five experts were invited to participate, of whom 24 accepted and completed all three rounds. Consensus was reached in 25/32 statements (78%). However, several statements addressing UGFS, single phlebectomies, patients with extensive comorbidities and morbid obesity remained equivocal. Conclusion Considerable consensus was reached within a group of experts but also some gaps in available research were highlighted.

Mohs micrographic surgery of rare cutaneous tumours.

BACKGROUND: Recurrence rates after Mohs micrographic surgery (MMS) for rare cutaneous tumours are poorly defined. OBJECTIVE: To investigate the recurrence rate after MMS for rare cutaneous tumours at a university centre. METHODS & MATERIALS: Retrospective review of all rare cutaneous tumours treated with MMS at a large university centre between January 2008 and December 2012. To detect all recurrences, patients were linked to The Nationwide Network and registry of histo- and cytopathology (PALGA). RESULTS: In total, 80 patients with 80 tumours were included. Tumour types included dermatofibrosarcoma protuberans (27), atypical fibroxanthoma (22), Merkel cell carcinoma (8), microcystic adnexal carcinoma (9), sebaceous carcinoma (6), extramammary Paget's disease (2) and other (6). Mean follow-up time was 3.7 years (standard deviation 1.4) during which two atypical fibroxanthomas recurred (2.5%). CONCLUSION: This large case series shows that MMS is an appropriate treatment for rare cutaneous tumours with a recurrence rate less than 3%. Preferably, MMS for rare cutaneous tumours is performed in experienced multidisciplinary centres to further improve the quality of treatment.

Reliability of diagnosis from Mohs slides: interpersonal and intrapersonal agreement on basal cell carcinoma presence and histological subtype.

BACKGROUND: The success of Mohs micrographic surgery (MMS) depends partly on the correct diagnosis of slides. OBJECTIVES: To determine reliability of diagnosis from Mohs slides. METHODS: This was a prospective study evaluating the reliability of diagnosis from Mohs slides of basal cell carcinoma (BCC) presence, BCC location on the slide and BCC subtype among six raters who independently assessed 50 Mohs slides twice with a 2-month interval. Slides were randomly selected whereby difficult-to-diagnose slides were oversampled. For each slide, a reference diagnosis was established by an expert panel. Cohen's kappa (κ) was calculated to determine levels of agreement interpersonally (rater vs. reference diagnosis) and intrapersonally (rater at T1 vs. T2). Multivariable logistic regression was used to determine independent risk factors for slides with interpersonal discordant diagnosis. The variables studied were BCC presence, whether a slide was scored as easy or difficult to diagnose, review duration of the 50 slides, profession and years of experience in diagnosis from Mohs slides. RESULTS: Interpersonal and intrapersonal agreement were substantial on BCC presence (κ = 0·66 and 0·68) and moderate on BCC subtype (κ = 0·45 and 0·55). Slides that were scored as difficult to diagnose were an independent risk factor for interpersonal discordant diagnosis on BCC presence (odds ratio 3·54, 95% confidence interval 1·81-6·84). CONCLUSIONS: Reliability of diagnosis from Mohs slides was substantial on BCC presence and moderate on BCC subtype. For slides that are scored difficult to diagnose, a second opinion is recommended to prevent misinterpretation and thereby recurrence of skin cancer.

Postural Diameter Change of the Saphenous Trunk in Chronic Venous Disease.

OBJECTIVE: The aim of this study was to analyze the correlation between the extent of diameter change from standing to supine position ("postural diameter change," PDC), and patient or duplex ultrasound (DUS) characteristics in lower limbs with and without saphenous trunk (ST) reflux. METHODS: Measurements were carried out in 193 limbs with primary great saphenous vein, anterior accessory saphenous vein, or small saphenous vein reflux, and 48 control limbs without ST reflux. The inner diameter of the ST was measured with DUS in the standing and lying positions. The PDC, calculated as a percentage, followed the formula: (standing diameter - lying diameter)/standing diameter × 100. Clinical findings (according to the highest "C" - of the CEAP classification), venous clinical severity score, body mass index (BMI), time of visit, and inside and outside temperature were documented. Limbs were divided into two groups using the median value of PDC as a cut off to increase interpretability of the analysis. RESULTS: The median PDC of the ST was 19% in limbs with ST reflux compared with 24% in control limbs (p = .16). In limbs with and without ST reflux, only older age and increased BMI were independently associated with a low PDC of the ST (R(2) 0.13). In limbs with ST reflux, median PDC was significantly lower in C4-C6 (16%, interquartile [IQR] 8-21) than in C0-C1 (23%, IQR 12-35) or C2-C3 limbs (21%, IQR 11-33; p = .016). In addition, PDC was significantly lower in veins with a large diameter (>7 mm) than in those with a small diameter (p = .003). CONCLUSION: Low PDC of the ST correlates with older age and increased BMI. Whether PDC might become a useful additional DUS tool to classify the severity of chronic venous disease and thereby influence the management strategy should be further investigated.

Predictors of Recanalization of the Great Saphenous Vein in Randomized Controlled Trials 1 Year After Endovenous Thermal Ablation.

OBJECTIVE/BACKGROUND: The objective was to identify predictors to develop and validate a prognostic model of recanalization of the great saphenous vein (GSV) in patients treated with endovenous thermal ablation (EVTA). METHODS: The search strategy of Siribumrungwong was updated between August 2011 and August 2014 using MEDLINE, Embase, and the Cochrane register to identify randomized controlled trials (RCTs), in which patients presenting with GSV reflux were treated with radiofrequency or endovenous laser ablation. Leg level data (n = 1226) of 15/23 selected RCTs were pooled. The primary outcome was recanalization of the GSV; the secondary outcome was change in health related quality of life (HRQoL) measured by the Chronic Venous Insufficiency quality of life Questionnaire or Aberdeen Varicose Vein Questionnaire 1 year post-procedure. Candidate predictors were age, sex, body mass index, clinical class, GSV diameter, saphenofemoral junction reflux, type of device, energy, and length of treated vein. RESULTS: At 1 year, 130 GSVs were recanalized (11%). Clinical class (odds ratio [OR] 2.1, 95% confidence interval [CI] 1.4-3.3) and diameter (OR 1.8, 95% CI 1.2-2.7) of the GSV were the strongest predictors of recanalization. Other predictors included in the final model were sex, type of device, and length of treated vein. The performance of the recanalization model was moderate, with an area under the curve above 0.717. GSV diameter, type of device, and amount of energy delivered were the only predictors of the change of HRQoL. None of the candidate predictors were included in the final HRQoL model (R(2) = .027). CONCLUSION: There are several important prognostic factors for GSV recanalization and change of HRQoL after EVTA. However, the performance of each model was unsatisfactory to allow use in clinical practice yet.

Randomized clinical trial of 940- versus 1470-nm endovenous laser ablation for great saphenous vein incompetence.

BACKGROUND: The independent effect of wavelength used for endovenous laser ablation (EVLA) on patient-reported outcomes, health-related quality of life (HRQoL), treatment success and complications has not yet been established in a randomized clinical trial. The aim was to compare two different wavelengths, with identical energy level and laser fibres, in patients undergoing EVLA. METHODS: Patients with great saphenous vein incompetence were randomized to receive 940- or 1470-nm EVLA. The primary outcome was pain at 1 week. Secondary outcomes were: patient satisfaction, duration of analgesia use and time without normal activities assessed at 1 week; HRQoL after 12 weeks; treatment success after 12 and 52 weeks; change in Venous Clinical Severity Score (VCSS) after 12 weeks; and adverse events at 1 and 12 weeks. RESULTS: A total of 142 legs were randomized (940-nm EVLA, 70; 1470-nm EVLA, 72). Patients in the 1470-nm laser group reported significantly less pain on a visual analogue scale than those in the 940-nm laser group: median (i.q.r.) score 3 (2-7) versus 6 (3-8) (P = 0.004). Duration of analgesia use was significantly shorter after 1470-nm EVLA: median (i.q.r.) 1 (0-3) versus 2 (0-5) days (P = 0.037). HRQoL and VCSS improved equally in both groups. There was no difference in treatment success rates. Complications were comparable in both groups, except for more superficial vein thrombosis 1 week after 1470-nm EVLA. CONCLUSION: EVLA using a 1470-nm wavelength fibre was associated with improved postoperative pain and a reduction in analgesia use in the first week after surgery compared with use of a 940-nm fibre. Treatment success and adverse event rates were similar. REGISTRATION NUMBER: NCT01637181 (http://www.clinicaltrials.gov).

Five-year results of a randomized clinical trial of conventional surgery, endovenous laser ablation and ultrasound-guided foam sclerotherapy in patients with great saphenous varicose veins.

BACKGROUND: A variety of techniques exist for the treatment of patients with great saphenous vein (GSV) varicosities. Few data exist on the long-term outcomes of these interventions. METHODS: Patients undergoing conventional surgery, endovenous laser ablation (EVLA) and ultrasound-guided foam sclerotherapy (UGFS) for GSV varicose veins were followed up for 5 years. Primary outcome was obliteration or absence of the treated GSV segment; secondary outcomes were absence of GSV reflux, and change in Chronic Venous Insufficiency quality-of-life Questionnaire (CIVIQ) and EuroQol - 5D (EQ-5D™) scores. RESULTS: A total of 224 legs were included (69 conventional surgery, 78 EVLA, 77 UGFS), 193 (86.2 per cent) of which were evaluated at final follow-up. At 5 years, Kaplan-Meier estimates of obliteration or absence of the GSV were 85 (95 per cent c.i. 75 to 92), 77 (66 to 86) and 23 (14 to 33) per cent in the conventional surgery, EVLA and UGFS groups respectively. Absence of above-knee GSV reflux was found in 85 (73 to 92), 82 (72 to 90) and 41 (30 to 53) per cent respectively. CIVIQ scores deteriorated over time in patients in the UGFS group (0.98 increase per year, 95 per cent c.i. 0.16 to 1.79), and were significantly worse than those in the EVLA group (-0.44 decrease per year, 95 per cent c.i. -1.22 to 0.35) (P = 0.013). CIVIQ scores for the conventional surgery group did not differ from those in the EVLA and UGFS groups (0.44 increase per year, 95 per cent c.i. -0.41 to 1.29). EQ-5D™ scores improved equally in all groups. CONCLUSION: EVLA and conventional surgery were more effective than UGFS in obliterating the GSV 5 years after intervention. UGFS was associated with substantial rates of GSV reflux and inferior CIVIQ scores compared with EVLA and conventional surgery. REGISTRATION NUMBER: NCT00529672 (http://www.clinicaltrials.gov).

Additional review of Mohs slides to optimize Mohs micrographic surgery.

BACKGROUND: One significant risk factor for recurrence after Mohs surgery is misinterpretation of slides. OBJECTIVES: To determine how often pathologists detected incompletely excised basal cell carcinoma (BCC) on Mohs slides and to determine risk factors for incompletely excised BCCs. METHODS: This retrospective study included 1653 BCCs treated with Mohs surgery in a university hospital between 2007 and 2011. For routine quality assurance, all slides were additionally reviewed by a pathologist within 1 week of the procedure. For this study, all cases that had divergent interpretations were re-evaluated by a Mohs surgeon and a pathologist. Mixed-effects logistic regression models with Mohs surgeon effects as random effects were used to determine risk factors for incompletely excised BCC. RESULTS: Incompletely excised BCCs were detected in 31 cases (2%), in which defects > 20 mm in diameter were an independent risk factor (odds ratio 3.58, 95% confidence interval 1.55-8.28). Other studied variables (i.e. aggressive subtype, previously treated BCC, location on nose and > 2 Mohs stages) did not affect the risk of incompletely excised BCCs. CONCLUSIONS: The additional review of Mohs slides might increase accurate interpretation, especially in large BCCs.

Management strategies for patients with varicose veins (C2-C6): results of a worldwide survey.

OBJECTIVES: This study evaluated how patient characteristics and duplex ultrasound findings influence management decisions of physicians with specific expertise in the field of chronic venous disease. METHODS: Worldwide, 346 physicians with a known interest and experience in phlebology were invited to participate in an online survey about management strategies in patients with great saphenous vein (GSV) reflux and refluxing tributaries. The survey included two basic vignettes representing a 47 year old healthy male with GSV reflux above the knee and a 27 year old healthy female with a short segment refluxing GSV (CEAP classification C2sEpAs2,5Pr in both cases). Participants could choose one or more treatment options. Subsequently, the basic vignettes were modified according to different patient characteristics (e.g. older age, morbid obesity, anticoagulant treatment, peripheral arterial disease), clinical class (C4, C6), and duplex ultrasound findings (e.g. competent terminal valve, larger or smaller GSV diameter, presence of focal dilatation). The authors recorded the distribution of chosen management strategies; adjustment of strategies according to characteristics; and follow up strategies. RESULTS: A total of 211 physicians (68% surgeons, 12% dermatologists, 12% angiologists, and 8% phlebologists) from 36 different countries completed the survey. In the basic case vignettes 1 and 2, respectively, 55% and 40% of participants proposed to perform endovenous thermal ablation, either with or without concomitant phlebectomies (p < .001). Looking at the modified case vignettes, between 20% and 64% of participants proposed to adapt their management strategy, opting for either a more or a less invasive treatment, depending on the modification introduced. The distribution of chosen management strategies changed significantly for all modified vignettes (p < .05). CONCLUSIONS: This study illustrates the worldwide variety in management preferences for treating patients with varicose veins (C2-C6). In clinical practice, patient related and duplex ultrasound related factors clearly influence therapeutic options.

Randomized clinical trial of endovenous laser ablation versus steam ablation (LAST trial) for great saphenous varicose veins.

BACKGROUND: The aim was to compare endovenous laser ablation (EVLA) and endovenous steam ablation (EVSA) for great saphenous varicose veins in a non-inferiority study. METHODS: Patients with primary great saphenous vein reflux were randomized to EVLA (940 nm) or EVSA (SVS™). Primary outcomes were treatment success (vein obliteration or abolition of reflux) [corrected] at 52 weeks, and Venous Clinical Severity Score (VCSS) at 12 weeks. Secondary outcomes were pain, satisfaction with treatment, duration of analgesia use and days lost from daily activities, changes in Aberdeen Varicose Vein Questionnaire (AVVQ) and EQ-5D™ scores after 12 weeks, and complications at 2 and 12 weeks. RESULTS: A total of 227 legs were treated (EVSA, 117; EVLA, 110); 36 legs treated with EVSA received a low dose and the remaining 81 a higher dose. At 1 year, the treatment success rate after high-dose EVSA was not inferior to that of EVLA: 92 (95 per cent confidence interval (c.i.) 86 to 98) versus 96 (92 to 100) per cent respectively. Changes in VCSS after 12 weeks were similar: -2·69 (95 per cent c.i. -2·34 to -3·04) and -2·51 (-2·10 to -2·93). AVVQ, EQ-5D™ and EQ VAS scores improved equally 12 weeks after both treatments. Patients treated with EVSA reported less postprocedural pain, fewer days of analgesia use, were more satisfied with therapy, and had a shorter convalescence. Complication rates were comparable. CONCLUSION: The 1-year treatment success of high-dose EVSA was not inferior to that of EVLA. Several secondary outcomes were in favour of EVSA. Registration number NCT02046967 (http://www.clinicaltrials.gov).

Temperature profiles of 980- and 1,470-nm endovenous laser ablation, endovenous radiofrequency ablation and endovenous steam ablation.

Endovenous thermal ablation (EVTA) techniques are very effective for the treatment of varicose veins, but their exact working mechanism is still not well documented. The lack of knowledge of mechanistic properties has led to a variety of EVTA protocols and a commercially driven dissemination of new or modified techniques without robust scientific evidence. The aim of this study is to compare temperature profiles of 980-and 1,470-nm endovenous laser ablation (EVLA), segmental radiofrequency ablation (RFA), and endovenous steam ablation (EVSA). In an experimental setting, temperature measurements were performed using thermocouples; raw potato was used to mimic a vein wall. Two laser wavelengths (980 and 1,470 nm) were used with tulip-tip fibers and 1,470 nm also with a radial-emitting fiber. Different powers and pullback speeds were used to achieve fluences of 30, 60, and 90 J/cm. For segmental RFA, 1 cycle of 20 s was analyzed. EVSA was performed with two and three pulses of steam per centimeter. Maximum temperature increase, time span of relevant temperature increase, and area under the curve of the time of relevant temperature increase were measured. In all EVLA settings, temperatures increased and decreased rapidly. High fluence is associated with significantly higher temperatures and increased time span of temperature rise. Temperature profiles of 980- and 1,470-nm EVLA with tulip-tip fibers did not differ significantly. Radial EVLA showed significantly higher maximum temperatures than tulip-tip EVLA. EVSA resulted in mild peak temperatures for longer durations than EVLA. Maximum temperatures with three pulses per centimeter were significantly higher than with two pulses. RFA temperature rises were relatively mild, resulting in a plateau-shaped temperature profile, similar to EVSA. Temperature increase during EVLA is fast with a high-peak temperature for a short time, where EVSA and RFA have longer plateau phases and lower maximum temperatures.

Endovenous simulated laser experiments at 940 nm and 1470 nm suggest wavelength-independent temperature profiles.

BACKGROUND: EVLA has proven to be very successful, but the optimum methods for energy delivery have still not been clarified. A better understanding of the mechanism of action may contribute to achieving a consensus on the best laser method and the most effective use of laser parameters, resulting in optimal clinical outcomes, maintaining high success rates with minimal adverse events. The aim of this study is to assess the impact of wavelength, pullback speed and power level on the endovenous temperature profile in an experimental setting. METHODS: In an experimental setting, temperature measurements were performed using thermocouples. The experimental set-up consisted of a transparent box in which a glass tube was fixed. Different laser parameters (wavelength and power) and 2 different pullback speeds (2 and 5 mm/s) were used. Thermocouples were placed at different distances from the fiber tip. Validity of the experimental setting was assessed by performing the same temperature measurements using a stripped varicose vein. The maximal temperature rise and the time span that the temperature was above collagen denaturation temperature were measured. RESULTS: The experiments showed that decreasing the pullback speed (2 mm/s) and increasing the power (up to 14 W) both cause higher maximal temperature and a longer time above the temperature for collagen denaturation. The use of different laser wavelengths (940 or 1470 nm) did not influence the temperature profile. CONCLUSION: The results of our experiments show that wavelength on its own has not been demonstrated to be an important parameter to influence the temperature profile.