Fluorescence imaging to visualize the recurrent laryngeal nerve during thyroidectomy procedures: analysis of 65 cases and 81 nerves.

BACKGROUND: Recurrent laryngeal nerve (RLN) injury after thyroidectomy is relatively common. Locating the RLN prior to thyroid dissection is paramount to avoid injury. We developed a fluorescence imaging system that permits nerve autofluorescence. We aimed to determine the sensitivity and specificity of fluorescence imaging at detecting the RLN relative to thyroid and other background tissue and compared it to white light. METHODS: In this prospective study, 65 patients underwent thyroidectomy from January to April 2022 (16 bilateral thyroid resections) using white and fluorescent light. Fluorescence intensity [relative fluorescence units (RFU)] was recorded for RLN, thyroid, and background. RFU mean, minimum, and maximum values were calculated using Image J software. Thirty randomly selected pairs of white and fluorescent light images were independently reviewed by two examiners to compare RLN detection rate, number of branches, and length and minimum width of nerves visualized. Parametric and nonparametric statistical analysis was performed. RESULTS: All 81 RNLs observed were visualized more clearly under fluorescence (mean intensity, µ = 134.3 RFU) than either thyroid (µ = 33.7, p < 0.001) or background (µ = 14.4, p < 0.001). Forest plots revealed no overlap between RLN intensity and that of either other tissue. Sensitivity and specificity for RLN were 100%. All 30 RLNs and all 45 nerve branches were clearly visualized under fluorescence, versus 17 and 22, respectively, with white light (both p < 0.001). Visible nerve length was 2.5 × as great with fluorescence as with white light (µ = 1.90 vs. 0.76 cm, p < 0.001). CONCLUSIONS: In 65 patients and 81 nerves, RLN detection was markedly and consistently enhanced with autofluorescence neuro-imaging during thyroidectomy, with 100% sensitivity and specificity.

Consensus Conference Statement on the General Use of Near-infrared Fluorescence Imaging and Indocyanine Green Guided Surgery: Results of a Modified Delphi Study.

BACKGROUND: In recent decades, the use of near-infrared light and fluorescence-guidance during open and laparoscopic surgery has exponentially expanded across various clinical settings. However, tremendous variability exists in how it is performed. OBJECTIVE: In this first published survey of international experts on fluorescence-guided surgery, we sought to identify areas of consensus and nonconsensus across 4 areas of practice: fundamentals; patient selection/preparation; technical aspects; and effectiveness and safety. METHODS: A Delphi survey was conducted among 19 international experts in fluorescence-guided surgery attending a 1-day consensus meeting in Frankfurt, Germany on September 8th, 2019. Using mobile phones, experts were asked to anonymously vote over 2 rounds of voting, with 70% and 80% set as a priori thresholds for consensus and vote robustness, respectively. RESULTS: Experts from 5 continents reached consensus on 41 of 44 statements, including strong consensus that near-infrared fluorescence-guided surgery is both effective and safe across a broad variety of clinical settings, including the localization of critical anatomical structures like vessels, detection of tumors and sentinel nodes, assessment of tissue perfusion and anastomotic leaks, delineation of segmented organs, and localization of parathyroid glands. Although the minimum and maximum safe effective dose of ICG were felt to be 1 to 2 mg and >10 mg, respectively, there was strong consensus that determining the optimum dose, concentration, route and timing of ICG administration should be an ongoing research focus. CONCLUSIONS: Although fluorescence imaging was almost unanimously perceived to be both effective and safe across a broad range of clinical settings, considerable further research remains necessary to optimize its use.

Nerve autofluorescence in near-ultraviolet light markedly enhances nerve visualization in vivo.

BACKGROUND: During surgery, surgeons must accurately localize nerves to avoid injuring them. Recently, we have discovered that nerves fluoresce in near-ultraviolet light (NUV) light. The aims of the current study were to determine the extent to which nerves fluoresce more brightly than background and vascular structures in NUV light, and identify the NUV intensity at which nerves are most distinguishable from other tissues. METHODS: We exposed sciatic nerves within the posterior thigh in five 250-300 gm Wistar rats, then observed them at four different NUV intensity levels: 20%, 35%, 50%, and 100%. Brightness of fluorescence was measured by fluorescence spectroscopy, quantified as a fluorescence score using Image-J software, and statistically compared between nerves, background, and both an artery and vein by unpaired Student's t tests with Bonferroni adjustment to accommodate multiple comparisons. Sensitivity, specificity, and accuracy were calculated for each NUV intensity. RESULTS: At 20, 35, 50, and 100% NUV intensity, fluorescence scores for nerves versus background tissues were 117.4 versus 40.0, 225.8 versus 88.0, 250.6 versus 121.4, and 252.8 versus 169.4, respectively (all p < 0.001). Fluorescence scores plateaued at 50% NUV intensity for nerves, but continued to rise for background. At 35%, 50%, and 100% NUV intensity, a fluorescence score of 200 was 100% sensitive, specific, and accurate identifying nerves. At 100 NUV intensity, artery and vein scores were 61.8 and 60.0, both dramatically lower than for nerves (p < 0.001). CONCLUSIONS: At all NUV intensities ≥ 35%, a fluorescence score of 200 is 100% accurate distinguishing nerves from other anatomical structures in vivo.

Nerve autofluorescence under near-ultraviolet light: cutting-edge technology for intra-operative neural tissue visualization in 17 patients.

BACKGROUND: Nerve visualization and the identification of other neural tissues during surgery is crucial for numerous reasons, including the prevention of iatrogenic nerve and neural structure injury and facilitation of nerve repair. However, current methods of intra-operative nerve detection are generally expensive, unproven, and/or technically challenging. Recently, we have documented, in both in vivo animal models and ex vivo human tissue, that nerves autofluorescence when viewed in near-ultraviolet light (NUV). In this paper, we describe our use of nerve autofluorescence to facilitate the visualization of nerves and other neural tissues intra-operatively in 17 patients undergoing a range of surgical procedures. METHODS: Employing the same prototype axon imaging system previously documented to markedly enhance nerve visualization in both in vivo animal and ex vivo human models, surgical fields were observed in 17 patients under both white and NUV light during parotid tumor resection (n = 3), thyroid tumor resection (n = 7), and surgery for peripheral nerve and spinal tumors and injury (n = 7). RESULTS: In all 17 patients, the intra-operative use of the imaging system both was feasible and markedly enhanced the localization of all neural tissues throughout their course within the surgical field. All 17 procedures were successful and devoid of any peri-operative complications or post-operative neurological deficits. CONCLUSIONS: Intra-operatively visualizing auto-fluorescent peripheral nerves and other neural tissues under NUV light is feasible in human patients across a range of clinical scenarios and appears to appreciably enhance nerve and other neural tissue visualization. Controlled studies to explore this technology further are needed.

Nerve spectroscopy: understanding peripheral nerve autofluorescence through photodynamics.

BACKGROUND: Being able to accurately identify sensory and motor nerves is crucial during surgical procedures to prevent nerve injury. We aimed to (1) evaluate the feasibility of performing peripheral human nerve visualization utilizing nerves' own autofluorescence in an ex-vivo model; (2) compare the effect of three different nerve fiber fixation methods on the intensity of fluorescence, indicated as the intensity ratio; and (3) similarly compare three different excitation ranges. METHODS: Samples from various human peripheral nerves were selected postoperatively. Nerve fibers were divided into three groups: Group A nerve fibers were washed with a physiologic solution; Group B nerve fibers were fixated with formaldehyde for 6 h first, and then washed with a physiologic solution; Group C nerve fibers were fixated with formaldehyde for six hours, but not washed afterwards. An Olympus IX83 inverted microscope was used for close-up image evaluation. Nerve fibers were exposed to white-light wavelength spectrums for a specific time frame prior to visualization under three different filters-Filter 1-LF405-B-OMF Semrock; Filter 2-U-MGFP; Filter 3-U-MRFPHQ Olympus, with excitation ranges of 390-440, 460-480, and 535-555, respectively. The fluorescence intensity of all images was subsequently analyzed using Image-J Software, and results compared by analysis of variance (ANOVA). RESULTS: The intensity ratios observed with Filter 1 failed to distinguish the different nerve fiber groups (p = 0.39). Conversely, the intensity ratios seen under Filters 2 and 3 varied significantly between the three nerve-fiber groups (p = 0.021, p = 0.030, respectively). The overall intensity of measurements was greater with Filter 1 than Filter 3 (p < 0.05); however, all nerves were well visualized by all filters. CONCLUSION: The current results on ex vivo peripheral nerve fiber autofluorescence suggest that peripheral nerve fiber autofluorescence intensity does not greatly depend upon the excitation wavelength or fixation methods used in an ex vivo setting. Implications for future nerve-sparing surgery are discussed.

Cognitive Accessibility and Support in Special Education.

This work describes an assistive technology development for cognitive support and training to be used by children of special education schools in Spain. Design is based on and guided by cognitive support findings coming from a long-term collaboration of a team of engineers (University of Zaragoza) and special education teachers (Alborada Special Education School, Zaragoza). The description starts by providing a structure of such findings in five cognitive-social areas (interface usability, virtual representations understanding, time orientation, self-awareness, and social interaction). Design requirements are extracted by applying those findings to four support services (home control, time orientation, behavior contention, and context anticipation). Technological system description follows, together with the degree of implementation and testing for each service. A major result is the benefit of using a services interface with the same structure and appearance as the alternative and augmentative communication system that children are already acquainted with. Based on regulatory conditions, the needed flexibility, and reduced available budgets, this support platform is built on mainstream technology and low-cost single-board computers with standard databases and free software packages. Results show evidence of benefit in children's cognitive and social performance, in addition to offering a technological tool for deeper educational research.

Time Orientation Technologies in Special Education.

A device to train children in time orientation has been designed, developed and evaluated. It is framed within a long-term cooperation action between university and special education school. It uses a specific cognitive accessible time display: Time left in the day is represented by a row of luminous elements initially on. Time passing is represented by turning off sequentially and gradually each luminous element every 15 min. Agenda is displayed relating time to tasks with standard pictograms for further accessibility. Notifications of tasks-to-come both for management support and anticipation to changes uses visual and auditory information. Agenda can be described in an Alternative and Augmentative Communication pictogram language already used by children, supporting individual and class activities on agenda. Validation has been performed with 16 children in 12 classrooms of four special education schools. Methodology for evaluation compares both prior and posterior assessments which are based in the International Classification of Functioning, Disability and Health (ICF) from the World Health Organization (WHO), together with observation registers. Results show consistent improvement in performances related with time orientation.

Detection of Parathyroid Autofluorescence Using Near-Infrared Imaging: A Multicenter Analysis of Concordance Between Different Surgeons.

BACKGROUND: Parathyroid glands (PGs) exhibit autofluorescence (AF) when excited by near-infrared laser. This multicenter study aims to analyze how this imaging could facilitate the detection of PGs during thyroidectomy and parathyroidectomy procedures. METHODS: This was a retrospective Institutional Review Board-approved analysis of prospectively collected data at three centers. Near-infrared fluorescence imaging (NIFI) was used to detect AF from PGs during thyroidectomy and parathyroidectomy procedures. Logistic regression analysis was performed to assess the utility of NIFI to identify PGs and concordance at these centers. RESULTS: Overall, 210 patients underwent total thyroidectomy (n = 95), thyroid lobectomy (n = 41), and parathyroidectomy (n = 74) (n = 70 per center). Using NIFI, AF was detected from 98% of visually identified PGs. Upon initial exploration, 46% of PGs were not visible to the naked eye due to coverage by soft tissue, but AF from these glands could be detected by NIFI without any further dissection. Overall, a median of one PG per patient was detected by NIFI in this fashion before being identified visually (p = nonsignificant between centers). On logistic regression, smaller PGs were more likely to be missed visually, but localized by AF on NIFI (odds ratio with increasing size, 0.91; p = 0.02). CONCLUSIONS: In our experience, NIFI facilitated PG identification by detecting their AF, before conventional recognition by the surgeon, in 37-67% of the time. Despite the variability in this rate across centers, there was a concordance in detecting AF from 97 to 99% of the PGs using NIFI. We suggest the incorporation of AF on NIFI alongside conventional visual cues to aid identification of PGs during neck operations.

Increased identification of parathyroid glands using near infrared light during thyroid and parathyroid surgery.

BACKGROUND: Parathyroid gland (PG) identification during thyroid and parathyroid surgery is challenging. Accidental parathyroidectomy increases the rate of postoperative hypocalcaemia. Recently, autofluorescence with near infrared light (NIRL) has been described for PG visualization. The aim of this study is to analyze the increased rate of visualization of PGs with the use of NIRL compared to white light (WL). MATERIALS AND METHODS: All patients undergoing thyroid and parathyroid surgery were included in this study. PGs were identified with both NIRL and WL by experienced head and neck surgeons. The number of PGs identified with NIRL and WL were compared. The identification of PGs was correlated to age, sex, and histopathological diagnosis. RESULTS: Seventy-four patients were included in the study. The mean age was 48.4 (SD ±13.5) years old. Mean PG fluorescence intensity (47.60) was significantly higher compared to the thyroid gland (22.32) and background (9.27) (p < 0.0001). The mean number of PGs identified with NIRL and WL were 3.7 and 2.5 PG, respectively (p < 0.001). The difference in the number of PGs identified with NIRL and WL and fluorescence intensity was not related to age, sex, or histopathological diagnosis, with the exception of the diagnosis of thyroiditis, in which there was a significant increase in the number of PGs visualized with NIRL (p = 0.026). CONCLUSION: The use of NIRL for PG visualization significantly increased the number of PGs identified during thyroid and parathyroid surgery, and the differences in fluorescent intensity among PGs, thyroid glands, and background were not affected by age, sex, and histopathological diagnosis.

A multi-collaborative ambient assisted living service description tool.

Collaboration among different stakeholders is a key factor in the design of Ambient Assisted Living (AAL) environments and services. Throughout several AAL projects we have found repeated difficulties in this collaboration and have learned lessons by the experience of solving real situations. This paper highlights identified critical items for collaboration among technicians, users, company and institutional stakeholders and proposes as a communication tool for a project steering committee a service description tool which includes information from the different fields in comprehensible format for the others. It was first generated in the MonAMI project to promote understanding among different workgroups, proven useful there, and further tested later in some other smaller AAL projects. The concept of scalable service description has proven useful for understanding of different disciplines and for participatory decision making throughout the projects to adapt to singularities and partial successes or faults of each action. This paper introduces such tool, relates with existing methodologies in cooperation in AAL and describes it with a example to offer to AAL community. Further work on this tool will significantly improve results in user-centered design of sustainable services in AAL.

AmI and deployment considerations in AAL services provision for elderly independent living: the MonAMI project.

The MonAMI project aims to investigate the feasibility of the deployment of open platforms for Ambient Assisted Living (AAL) services provision based on Ambient Intelligence (AmI) and to test user acceptance and the usability of the services. Services were designed to provide support in the areas of environmental control, security, well-being and leisure. These services were installed and evaluated in a Spanish geriatric residence. The participants included elderly persons with disabilities, nursing home care givers and informal carers. The concept of the open platform proved to be satisfactory for the provision of the services in a context aware framework. Furthermore, the usability of the technology was viewed positively and the overall results indicate that this system has the potential to prolong independent living at home for elderly people with disabilities. Deployment was proven successful and awareness of open-platform AAL service delivery was raised in local communities throughout Europe.

Use of fluorescence imaging and indocyanine green during thyroid and parathyroid surgery: Results of an intercontinental, multidisciplinary Delphi survey.

BACKGROUND: In recent years, fluorescence imaging-relying both on parathyroid gland autofluorescence under near-infrared light and angiography using the fluorescent dye indocyanine green-has been used to reduce risk of iatrogenic parathyroid injury during thyroid and parathyroid resections, but no published guidelines exist regarding its use. In this study, orchestrated by the International Society for Fluorescence Guided Surgery, areas of consensus and nonconsensus were examined among international experts to facilitate future drafting of such guidelines. METHODS: A 2-round, online Delphi survey was conducted of 10 international experts in fluorescence imaging use during endocrine surgery, asking them to vote on 75 statements divided into 5 modules: 1 = patient preparation and contraindications to fluorescence imaging (n = 11 statements); 2 = technical logistics (n = 16); 3 = indications (n = 21); 4 = potential advantages and disadvantages of fluorescence imaging (n = 20); and 5 = training and research (n = 7). Several methodological steps were taken to minimize voter bias. RESULTS: Overall, parathyroid autofluorescence was considered better than indocyanine green angiography for localizing parathyroid glands, whereas indocyanine green angiography was deemed superior assessing parathyroid perfusion. Additional surgical scenarios where indocyanine green angiography was thought to facilitate surgery are (1) when >1 parathyroid gland requires resection; (2) during redo surgeries, (3) facilitating parathyroid autoimplantation; and (4) for the predissection visualization of abnormal glands. Both parathyroid autofluorescence and indocyanine green angiography can be used during the same procedure and employing the same imaging equipment. However, further research is needed to optimize the dose and timing of indocyanine green administration. CONCLUSION: Though further research remains necessary, using fluorescence imaging appears to have uses during thyroid and parathyroid surgery.

[Laparoscopic approach in the treatment of malignant adrenal tumours]. / Abordaje laparoscópico en el tratamiento de las tumoraciones adrenales malignas.

BACKGROUND: Malignant primary or secondary adrenal tumours are uncommon. For most of them early surgery with adrenalectomy is the only means of cure. Although controversy exists on this issue, the increasing experience in laparoscopic surgery extends the indication for laparoscopic adrenalectomy to potentially malignant and to metastatic adrenal tumours. Our aim was to evaluate the technical feasibility of laparoscopic adrenalectomy for malignant neoplasias, describing the results of our consecutive series of patients. MATERIAL AND METHODS: We retrospectively analysed 13 patients who underwent laparoscopic adrenalectomy for malignant neoplasia between March 1999 and June 2009, at the Hospital de Clínicas of the Universidad of Buenos Aires and at the Hospital Alemán of Buenos Aires. A transperitoneal laparoscopic approach was used in all patients. The mean follow up was 37.9 months (2-84). RESULTS: Thirteen laparoscopic adrenalectomies were performed due to malignant neoplasia. Mean age was 55.2+12 years. The relationship between male and female was 10/3. Five patients had an adrenal carcinoma, 1 patient a malignant phaeochromocytoma, and 7 patients had metastatic tumours. Three patients required conversion to laparotomy. Average operation time was 146.4 min. There were two perioperative complications and no mortality. Average length of hospital stay was 4.6 days (1-35). The survival at 3 years was 46%. The cause of death was the underlying disease in all cases. CONCLUSION: Laparoscopic adrenalectomy is a reasonable technique for malignant adrenal tumours, when the open oncological resection can be reproduced by the laparoscopic approach.

Randomized Controlled Trial Comparing White Light with Near-Infrared Autofluorescence for Parathyroid Gland Identification During Total Thyroidectomy.

BACKGROUND: Parathyroid glands are difficult to identify during total thyroidectomies, and accidental resection can lead to problematic postoperative hypocalcemia. Our main goals were to evaluate the effectiveness of using near-infrared light (NIRL) autofluorescence intraoperatively for parathyroid gland identification and to measure its impact on postoperative hypocalcemia incidence. STUDY DESIGN: Total thyroidectomies were performed on 170 patients with different thyroid pathologies, block-randomized (1:1) into 2 equal groups. Among controls, traditional overhead white light (WL) was used throughout. In the experimental group, NIRL was used to enhance parathyroid gland recognition before thyroid dissection. The number of parathyroid glands identified was compared after thyroid dissection in controls using WL vs pre-dissection in the experimental using NIRL and with WL vs NIRL before thyroid dissection in the experimental group. Postoperative serum calcium levels and hypocalcemia rates were compared. RESULTS: The mean number of parathyroid glands identified pre-dissection with NIRL was the same identified post-dissection with WL (3.5 vs 3.6). In the experimental group, converting from WL to NIRL increased the number of glands detected from 2.6 to 3.5 (p < 0.001), and revealed at least 1 previously missed gland in 67.1% of patients. Calcium levels ≤7.5 mg/dL were one-tenth as common in the NIRL group (p = 0.005). The adjusted odds of hypocalcemia developing increased by 15% for every 5-g increase in thyroid gland weight (odds ratio 1.15; 95% CI 1.06 to 1.25). All hypocalcemia resolved within 6 months. CONCLUSIONS: Using NIRL during thyroidectomy increases intraoperative identification of parathyroid glands, enhances their detection before thyroid dissection, and decreases the incidence of postoperative hypocalcemia.

[Study of the sentinel lymph node. Diagnosis and treatment of cutaneous malignant melanoma stages I and II]. / Estudio del ganglio centinela diagnostico y tratamiento del melanoma maligno cutaneo, estadios I y II.

Survival at 5 years of patients with localized primary malignant melanoma is about 80%, compared with a 35% survival in case of lymph nodes involvement. Sentinel lymph node(s) from 45 subjects with diagnosis of malignant melanoma stage I or II was/were studied with hematoxylin-eosin (HE), immunohistochemistry (IHC) and molecular biology (MB) techniques. The population was divided into three groups: HE-/IHC+/MB+, where 67% patients died; HE-/IHC-/MB+, where 57% died; and HE-/IHC-/MB-, where 100% of the patients are alive, with no lymphadenectomy and a median follow-up of 60 months. Those subjects who showed negativity with all the three methods had a null recurrence rate. Data herein obtained suggest a new molecular oncological staging, which would allow the selection of patients with submicroscopic metastases for a complete treatment. Moreover, several patients with no lymph node metastases should not undergo lymphadenectomies, and overtreatment could therefore be avoided.

Cutting Edge in Thyroid Surgery: Autofluorescence of Parathyroid Glands.

BACKGROUND: Identification of parathyroid glands may be challenging during thyroid and parathyroid surgery. Accidental resection of the glands may increase the morbidity of the surgery. The aim of this study was to evaluate accuracy in identification of autofluorescent parathyroid glands with the use of near infrared light in real time. STUDY DESIGN: Patients undergoing thyroid and parathyroid surgery between June and August 2015 were included in the study. During the procedure, the surgical field was exposed to near infrared laser light in order to analyze the intensity of the fluorescence of different tissues (parathyroid glands, thyroid glands, and background). Surgical images were recorded and analyzed. RESULTS: Twenty-eight patients were included in the study. Nineteen patients were women and 9 were men. Seven patients had primary hyperparathyroidism, 4 had hyperthyroidism, 3 had goiters, and 11 had thyroid cancer. Three patients had mixed pathologies, including 2 patients with thyroid cancer and primary hyperparathyroidism and 1 patient with goiter and primary hyperparathyroidism. Identification of autofluorescent parathyroid glands was achieved in all patients with near infrared light. The mean fluorescent intensity of parathyroid glands was 40.6 (±26.5), thyroid glands 31.8 (±22.3), and background 16.6 (±15.4). Parathyroid glands demonstrated statistically higher fluorescence intensity compared with the thyroid gland and background (p < 0.0014). No postoperative hypocalcemia or other complications related to the surgery were registered. CONCLUSIONS: Visualization of autofluorescent parathyroid glands with the use of near infrared light allows high rates of parathyroid gland identification and could be a safe, feasible, and noninvasive method for intraoperative identification of parathyroid glands in real time. Further clinical studies must be performed to determine the cost-effectiveness and clinical application of this method.

Comparación entre los melanomas de cabeza y cuello con los de tronco y extremidades / Comparison between head and neck melanomas with trunk and extremity melanomas

Antecedentes: los melanomas en cabeza y cuello (MCC) han sido asociados con factores pronósticos diferentes de aquellos en otras localizaciones. Objetivo: comparar características demográficas, clínicas y resultados del tratamiento quirúrgico de pacientes con MCC y pacientes con melanomas en tronco y extremidades (MTE). Material y métodos: se llevó a cabo una revisión retrospectiva de las historias clínicas de pacientes operados por melanoma entre enero de 2012 y diciembre de 2017. Quince pacientes (22,3%) tuvieron MCC y 52 (77,7%) MTE. Resultados: ambos grupos tuvieron edad similar (63,8 ± 21,1 versus 58,5 ± 16), pero los MCC mostraron una tendencia con predominio masculino (80% versus 61,3%). Los MCC tuvieron menor espesor tumoral que los MTE (2,07 versus 5,5 mm) y mayor porcentaje de melanoma in situ, 5 (33,3%) versus 8 (15,3%), pero requirieron vaciamientos ganglionares más a menudo (33% versus 25%) así como reconstrucción del defecto primario con colgajos locales y miocutáneos. Durante el seguimiento, en el grupo de MCC, dos pacientes desarrollaron recidivas locales que fueron extirpadas, y otros tres desarrollaron metástasis a distancia en pulmón, intestino delgado y abdomen y fallecieron por la enfermedad; en el grupo de MTE un paciente tuvo recidiva local y cinco fallecieron de metástasis sistémicas. El tamaño de la muestra no permitió aplicar pruebas de significación entre las diferencias encontradas. Conclusión: los MCC se presentan en un amplio rango de edad y estadios, y tuvieron algunas diferencias clínicas con el MTE. Los defectos producidos por la extirpación de la lesión primaria requieren procedimientos reconstructivos más complejos la mayoría de las veces y se aconseja un abordaje multidisciplinario.

Background: Head and neck melanomas (HNMs) have been associated with prognostic factors different from those on other locations. Objective: The goal of the present study was to compare the demographic and clinical characteristics and the outcomes of surgical treatment between patients with HNM and those with trunk and extremity melanoma (TEM). Material and methods: The clinical records of patients undergoing surgery for melanoma between October 2014 and April 2018 were retrospectively reviewed. Fifteen patients (22.3%) had HNM and 52 (77.7) presented TEM. Results: There were no differences in age between both groups (63.8 ± 21.1 versus 58.5 ± 16), but there was a trend toward higher percentage of men in the HNM group (80% versus 61.3%). Patients with HNM had lower tumor thickness than those with TEM (2.07 versus 5.5 mm), higher incidence of melanoma in situ [5 (33.3%) versus 8 (15.3%)]; lymph node resection was more common (33% versus 25%) as well as reconstruction of the primary defect with local and musculocutaneous flaps. During follow-up, two patients in the HNM group developed local recurrences that were excised and three presented distant metastases in the lung, small bowel and abdomen and finally died due to the disease. In the TEM group, one patient had local recurrence and five died due to systemic metastases. The sample size was not sufficient to assess statistically significant differences. Conclusion: Head and neck melanomas occur in a wide age range and stages and has some clinical differences with TEM. The defects produced after the excision of the primary lesion often require more complex procedures and should be managed with a multidisciplinary approach.

Voice changes after thyroidectomy without recurrent laryngeal nerve injury.

BACKGROUND: Injury of the inferior laryngeal nerve is not the only cause of voice alteration after thyroidectomy; many patients notice minimal changes immediately after operation, without evidence of inferior laryngeal nerve damage. We hypothesized that there may be other causes for voice modification, such as injuries of the superior laryngeal nerve, prethyroid strap muscles, and cricothyroid muscles. We describe voice changes after total thyroidectomy, without inferior laryngeal nerve injury, using a computer program to objectively compare different patterns of voice. STUDY DESIGN: Forty-six consecutive patients who underwent total thyroidectomy were studied between March 1997 and December 1999. Acoustic voice analysis was performed preoperatively and at the second, fourth, and sixth postoperative months using a microphone adapted to a personal computer. Parameters measured were intensity of the voice (Shimmer) and fundamental frequency (Fo). RESULTS: No complications occurred during operation or in the postoperative period. Voice fatigue during phonation was the most common symptom after thyroidectomy. Forty patients (87%) stated that their voices had changed since the operation, and common complaints were voice alteration while speaking loudly, changes in voice pitch, and voice disorder while singing. Changes in the Fo and Shimmer values in smokers versus nonsmokers were similar (Fo overall, p = 0.56; Shimmer overall, p = 0.66), as were the same parameters in benign and malignant pathologies (Fo overall, p = 0.66; Shimmer overall, p = 0.67). CONCLUSIONS: Voice changes after uncomplicated thyroidectomy occur and can be objectively measured. This is important in the preoperative counseling of patients before thyroidectomy, for ethical and legal purposes.

Sentinel lymph node: detection of micrometastases of melanoma in a molecular study.

INTRODUCTION: Lymph node status in patients with cutaneous malignant melanoma is the most important prognostic factor. Patients with clinically positive nodes (stage III) should undergo therapeutic lymphadenectomy; however, the surgical approach to the regional disease in patients with negative clinical examination (stage I and II) is still controversial. Selective lymphadenectomy consists of the intraoperative identification of the first node in the nodal basin, the sentinel lymph node (SLN). Routine examination, serial sectioning, and immunohistochemistry may underestimate the presence of tumor cells. PCR is a molecular biology technique that may be useful for the detection of malignant melanoma nodal metastases in the SLN. AIM: The aim of this study was to use tyrosinase messenger RNA (mRNA) amplification for the detection of micrometastases in fresh frozen SLNs. METHODS: 46 hematoxylin-eosin (HE)-negative sentinel node samples from 42 patients with malignant melanoma were included in this study. Formalin-fixed paraffin-embedded sections were immunostained with S-100 protein and HMB-45. A central portion of the node was submitted for PCR. This method was accomplished with a combination of reverse transcription and amplification of the tyrosinase complementary DNA and double- round PCR (nested reverse transcriptase [RT]-PCR). RESULTS: In 1 of the 42 SLN-negative patients, immunohistochemistry stains allowed the detection of micrometastases. With molecular biology, 14 of the 42 SLN patients were positive (33%); in another 12 (29%), only the nested RT-PCR was positive. Of the 42 patients, 24 were put into 3 groups and followed for a 5-year period with 1, 7, and 16 patients, respectively, in the groups. The first group involved 1 patient who had provided 2 SLN samples that were found to be SLN-positive using both techniques, immunohistochemistry stains and nested RT-PCR (he had hepatic metastasis and died 24 months after diagnosis). The second group, with only nested RT-PCR positive SLN samples, included 7 of 12 patients who were followed and had a median survival of 37 months; 4 died of widespread metastatic disease, the other 3 patients had event-free survival, but 1 consented to undergo a therapeutic lymphadenectomy as a result of a positive test. The last group consisting of 16 of 32 patients, with complete 5-year survival, who were SLN-negative with both techniques, immunohistochemistry stains and nested RT-PCR. Fourteen of the 16 (88%) were event-free survival during the follow-up, and 2 had local relapse. CONCLUSION: Tyrosinase mRNA amplification may be a negative prognostic factor for the detection of micrometastases in fresh frozen SLNs using molecular biology techniques.

Autofluorescencia: un método innovador en la identificación intraoperatoria de adenomas paratiroideos / Autofluorescence: an innovative method in the intraoperative identification of parathyroid adenomas

RESUMEN Introducción El tratamiento definitivo del hiperparatiroidismo primario es la resección quirúrgica de la glándula paratiroidea anómala. Su identificación resulta un desafío aun para cirujanos expertos. Hasta el momento no se han descripto métodos inocuos y efectivos para la identificación intraoperatoria de las glándulas. Tenemos como objetivo reportar la experiencia del uso de autofluorescencia en la identificación de las glándulas paratiroideas. Método Se incluyeron pacientes con hiperparatiroidismo primario evaluados preoperatoriamente con laboratorio, ecografía cervical y centellografía con Tc-99 MIBI. Durante el acto operatorio se utilizó un método de autofluorescencia (VINFLUO-P) para identificar las glándulas paratiroides (GP). Se analizó la intensidad lumínica de las (GP) normales y anómalas (AP) y distintas covariables. Se dosó PTH ultra rápida post resección del AP y se evaluó la histopatología de la pieza intraoperatoriamente. Resultados Se incluyeron 59 pacientes. La ecografía preoperatoria predijo la ubicación correcta en el 68% y el centellograma Tc-99 MIBI el 75% de los AP. La localización más frecuente fue inferior derecha (29%). El VINFLUO-P facilitó la visualización de las GP y los AP en el 100% de los pacientes con un aumento del 27% respecto a la luz blanca. Se evidenció un descenso postoperatorio de PTH del 76,44% y de la calcemia en 1,8 mg/dl. La intensidad de la luz reflejada por los AP fue mayor que la de las GP normales (p <0,001). Se observó una relación lineal entre PTH e intensidad lumínica de AP. (CC = 0,448; p = 0,045). El patrón arquitectural sólido de los AP evidenció una asociación negativa (CC = -0,4709 p = 0,03). Conclusión La utilización del VINFLUO-P demostró ser efectivo para la identificación de las GP normales y patológicas. Las glándulas anómalas resultaron con mayor fluorescencia que los tejidos normales.

ABSTRACT Introduction The treatment of primary hyperparathyroidism consists on the resection of the abnormal parathyroid gland (PG). Identification of PGs is challenging even for expert surgeons. Currently, there are no effective and harmless methods for intraoperative identification of PGs. The aim of this study is to report our experience with the identification of PGs using autofluorescence. Materials and methods Patients with diagnosis of primary hyperparathyroidism were included in the study. Patients were preoperatively worked up with labs [parathyroid hormone (PTH), serum calcium], neck ultrasound (US) and Technetium (99mTc) sestamibi. The parathyroid gland Intraoperative fluorescent visualization (PG-IFV) method was used during the surgery to identify PGs. The fluorescent intensity ratio of normal PGs and parathyroid adenomas (PA) was analyzed and correlated to different variables. All patients underwent a post-resection rapid PTH analysis and frozen section. Results Fifty-nine patients were included in the study. The US accurately predicted the location of the PA in 68% of the cases, while 99mTc sestamibi was accurate in 75% of the cases. The most frequently reported localization of the adenoma was right inferior (29%). PG-IFV facilitated the visualization of the PGs in 100% of the cases, with a 27% increase in the visualization of the PGs when compared to white light. The postoperative PTH decreased 76.4% and the calcium 1.8 mg/dl. The fluorescent intensity ratio of the PAs was significantly higher than normal PGs (44.4 vs 27.2, p <0.001). There was positive correlation between the PTH and the fluorescent intensity ratio of the PAs [Spearman's correlation coefficient (SCC) = 0.448; p = 0.045]. The solid histoarchitectural pattern of the PAs presented a negative correlation with fluorescent intensity ratio (SCC = -0.4709, p = 0.03). Conclusion The use of PG-IFV is an effective method for intraoperative identification of normal and abnormal PGs. The fluorescent intensity ratio of abnormal PGs was significantly higher than normal PGs.