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1.
Int J Comput Assist Radiol Surg ; 19(1): 171-180, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37747574

RESUMEN

INTRODUCTION: Sentinel lymph node biopsy for oral and oropharyngeal squamous cell carcinoma is a well-established staging method. One variation is to inject a radioactive tracer near the primary tumor of the patient. After a few minutes, audio feedback from an external hand-held [Formula: see text]-detection probe can monitor the uptake into the lymphatic system. Such probes place a high cognitive load on the surgeon during the biopsy, as they require the simultaneous use of both hands and the skills necessary to correlate the audio signal with the location of tracer accumulation in the lymph nodes. Therefore, an augmented reality (AR) approach to directly visualize and thus discriminate nearby lymph nodes would greatly reduce the surgeons' cognitive load. MATERIALS AND METHODS: We present a proof of concept of an AR approach for sentinel lymph node biopsy by ex vivo experiments. The 3D position of the radioactive [Formula: see text]-sources is reconstructed from a single [Formula: see text]-image, acquired by a stationary table-attached multi-pinhole [Formula: see text]-detector. The position of the sources is then visualized using Microsoft's HoloLens. We further investigate the performance of our SLNF algorithm for a single source, two sources, and two sources with a hot background. RESULTS: In our ex vivo experiments, a single [Formula: see text]-source and its AR representation show good correlation with known locations, with a maximum error of 4.47 mm. The SLNF algorithm performs well when only one source is reconstructed, with a maximum error of 7.77 mm. For the more challenging case to reconstruct two sources, the errors vary between 2.23 mm and 75.92 mm. CONCLUSION: This proof of concept shows promising results in reconstructing and displaying one [Formula: see text]-source. Two simultaneously recorded sources are more challenging and require further algorithmic optimization.


Asunto(s)
Realidad Aumentada , Biopsia del Ganglio Linfático Centinela , Humanos , Biopsia del Ganglio Linfático Centinela/métodos , Ganglios Linfáticos/patología , Estadificación de Neoplasias
2.
PLoS One ; 16(4): e0250558, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33930063

RESUMEN

An integrated augmented reality (AR) surgical navigation system that potentially improves intra-operative visualization of concealed anatomical structures. Integration of real-time tracking technology with a laser pico-projector allows the surgical surface to be augmented by projecting virtual images of lesions and critical structures created by multimodality imaging. We aim to quantitatively and qualitatively evaluate the performance of a prototype interactive AR surgical navigation system through a series of pre-clinical studies. Four pre-clinical animal studies using xenograft mouse models were conducted to investigate system performance. A combination of CT, PET, SPECT, and MRI images were used to augment the mouse body during image-guided procedures to assess feasibility. A phantom with machined features was employed to quantitatively estimate the system accuracy. All the image-guided procedures were successfully performed. The tracked pico-projector correctly and reliably depicted virtual images on the animal body, highlighting the location of tumour and anatomical structures. The phantom study demonstrates the system was accurate to 0.55 ± 0.33mm. This paper presents a prototype real-time tracking AR surgical navigation system that improves visualization of underlying critical structures by overlaying virtual images onto the surgical site. This proof-of-concept pre-clinical study demonstrated both the clinical applicability and high precision of the system which was noted to be accurate to <1mm.


Asunto(s)
Realidad Aumentada , Imagen Multimodal , Cirugía Asistida por Computador/métodos , Animales , Xenoinjertos , Humanos , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética , Ratones , Fantasmas de Imagen , Interfaz Usuario-Computador
3.
EJNMMI Phys ; 6(1): 10, 2019 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-31214811

RESUMEN

BACKGROUND: Squamous cell carcinoma in the head and neck region is one of the most widespread cancers with high morbidity. Classic treatment comprises the complete removal of the lymphatics together with the cancerous tissue. Recent studies have shown that such interventions are only required in 30% of the patients. Sentinel lymph node biopsy is an alternative method to stage the malignancy in a less invasive manner and to avoid overtreatment. In this paper, we present a novel approach that enables a future augmented reality device which improves the biopsy procedure by visual means. METHODS: We propose a co-calibration scheme for axis-aligned miniature cameras with pinholes of a gamma ray collimating and sensing device and show results gained by experiments, based on a calibration target visible for both modalities. RESULTS: Visual inspection and quantitative evaluation of the augmentation of optical camera images with gamma information are congruent with known gamma source landmarks. CONCLUSIONS: Combining a multi-pinhole collimator with axis-aligned miniature cameras to augment optical images using gamma detector data is promising. As such, our approach might be applicable for breast cancer and melanoma staging as well, which are also based on sentinel lymph node biopsy.

4.
Phys Med Biol ; 64(11): 115028, 2019 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-30965313

RESUMEN

BACKGROUND: When locating the sentinel lymph node (SLN), surgeons use state-of-the-art imaging devices, such as a 1D gamma probe or less widely spread a 2D gamma camera. These devices project the 3D subspace onto a 1D respectively 2D space, hence loosing accuracy and the depth of the SLN which is very important, especially in the head and neck area with many critical structures in close vicinity. Recent methods which use a multi-pinhole collimator and a single gamma detector image try to gain a depth estimation of the SLN. The low intensity of the sources together with the computational cost of the optimization process make the reconstruction in real-time, however, very challenging. RESULTS: In this paper, we use an optimal design approach to improve the classical pinhole design, resulting in a non-symmetric distribution of the pinholes of the collimator. This new design shows a great improvement of the accuracy when reconstructing the position and depth of the radioactive tracer. Then, we introduce our Sentinel lymph node fingerprinting (SLNF) algorithm, inspired by MR-fingerprinting, for fast and accurate reconstruction of the tracer distribution in 3D space using a single gamma detector image. As a further advantage, the method requires no pre-processing, i.e. filtering of the detector image. The method is very stable in its performance even for low exposure times. In our ex vivo experiments, we successfully located multiple Technetium 99m (Tc-99m) sources with an exposure time of only one second and still, with a very small L 2-error. CONCLUSION: These promising results under short exposure time are very encouraging for SLN biopsy. Although, this device has not been tested on patients yet, we believe: that this approach will give the surgeon accurate 3D positions of the SLN and hence, can potentially reduce the trauma for the patient.


Asunto(s)
Cintigrafía/instrumentación , Cintigrafía/métodos , Ganglio Linfático Centinela/diagnóstico por imagen , Azufre Coloidal Tecnecio Tc 99m , Humanos , Radiofármacos , Ganglio Linfático Centinela/patología , Biopsia del Ganglio Linfático Centinela
5.
Head Neck ; 38(6): 939, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27166754
6.
Clin Nucl Med ; 41(7): 534-42, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27088386

RESUMEN

PURPOSE: Nuclear imaging plays a crucial role in lymphatic mapping of oral cancer. This evaluation represents a subanalysis of the original multicenter SENT trial data set, involving 434 patients with T1-T2, N0, and M0 oral squamous cell carcinoma. The impact of acquisition techniques, tracer injection timing relative to surgery, and causes of false-negative rate were assessed. METHODS: Three to 24 hours before surgery, all patients received a dose of Tc-nanocolloid (10-175 MBq), followed by lymphoscintigraphy. According to institutional protocols, all patients underwent preoperative dynamic/static scan and/or SPECT/CT. RESULTS: Lymphoscintigraphy identified 723 lymphatic basins. 1398 sentinel lymph nodes (SNs) were biopsied (3.2 SN per patient; range, 1-10). Dynamic scan allowed the differentiation of sentinel nodes from second tier lymph nodes. SPECT/CT allowed more accurate anatomical localization and estimated SN depth more efficiently. After pathological examination, 9.9% of the SN excised (138 of 1398 SNs) showed metastases. The first neck level (NL) containing SN+ was NL I in 28.6%, NL IIa in 44.8%, NL IIb in 2.8%, NL III in 17.1%, and NL IV in 6.7% of positive patients. Approximately 96% of positive SNs were localized in the first and second lymphatic basin visualized using lymphoscintigraphy. After neck dissection, the SN+ was the only lymph node containing metastasis in approximately 80% of patients. CONCLUSIONS: Best results were observed using a dynamic scan in combination with SPECT/CT. A shorter interval between tracer injection, imaging, and surgery resulted in a lower false-negative rate. At least 2 NLs have to be harvested, as this may increase the detection of lymphatic metastases.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico por imagen , Carcinoma de Células Escamosas/secundario , Metástasis Linfática/diagnóstico por imagen , Linfocintigrafia/métodos , Neoplasias de la Boca/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Femenino , Humanos , Ganglios Linfáticos/patología , Metástasis Linfática/patología , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/patología , Cuello/patología , Medicina Nuclear , Cintigrafía , Radiofármacos/administración & dosificación , Ganglio Linfático Centinela/diagnóstico por imagen , Tomografía Computarizada por Tomografía Computarizada de Emisión de Fotón Único , Encuestas y Cuestionarios
7.
Head Neck ; 38(2): 253-9, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25270792

RESUMEN

BACKGROUND: Adult laryngotracheal reconstruction for airway stenosis and after oncologic ablation can be extremely challenging. METHODS: Patients with the above conditions not amenable to or refractory to conventional treatments were offered specialized reconstruction by wrapping a contoured costal cartilage graft with a vascularized microvascular carrier. All constructs were lined with buccal mucosa grafts. Decannulation rates, quality of life questionnaires, and pulmonary function tests were performed and analyzed. RESULTS: Eleven patients underwent this procedure, 6 for stenosis and 5 for laryngotracheal oncologic defects. Ten patients were successfully decannulated after the procedure (91%). Median time to decannulation was 4 months. At mean follow-up of 76 months, all evaluated patients had a serviceable voice, tolerated a normal diet, and had minimal subjective shortness of breath. CONCLUSION: Vascularized composite autograft can be successfully used to treat severe subglottic stenosis or reconstruct large laryngotracheal defects not amenable to or refractory to conventional treatments.


Asunto(s)
Cartílago Costal/trasplante , Laringoestenosis/cirugía , Laringe/cirugía , Tráquea/cirugía , Estenosis Traqueal/cirugía , Adulto , Anciano , Autoinjertos , Cartílago Costal/irrigación sanguínea , Femenino , Estudios de Seguimiento , Humanos , Enfermedades de la Laringe/complicaciones , Enfermedades de la Laringe/cirugía , Laringoestenosis/etiología , Laringe/lesiones , Masculino , Persona de Mediana Edad , Mucosa Bucal/trasplante , Estudios Retrospectivos , Neoplasias de la Tiroides/cirugía , Tráquea/lesiones , Estenosis Traqueal/etiología , Adulto Joven
8.
BMC Med Imaging ; 15: 60, 2015 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-26714448

RESUMEN

BACKGROUND: [18F]FDG-PET/CT imaging is broadly used in head and neck cancer (HNSCC) patients. CT perfusion (CTP) is known to provide information about angiogenesis and blood-flow characteristics in tumors. The aim of this study was to evaluate the potential relationship of FDG-parameters and CTP-parameters in HNSCC preand post-therapy and the potential prognostic value of a combined PET/CT with CTP. METHODS: Thirteen patients with histologic proven HNSCC were prospectively included. All patients underwent a combined PET/CT with integrated CTP before and after therapy. Pre- and post-therapeutic data of CTP and PET of the tumors were compared. Differences were tested using Spearman's rho test and Pearson's correlation. A p-value of p <0.05 was considered statistically significant. Correlations were calculated using Pearson's correlation. Bootstrap confidence intervals were calculated to test for additive confidence intervals. RESULTS: Three patients died due to malignancy recurrence, ten patients were free of recurrence until the end of the follow-up period. Patients with recurrent disease had significantly higher initial CTP-values compared to the recurrence-free patients: BFpre 267.4 (171.2)ml/100 mg/min, BVpre 40.9 (8.4)ml/100 mg and MTTpre 8.2 (6.1)sec. No higher SUVs initially but significantly higher TLG compared to patients without recurrence were found. Post-therapeutic PET-values differed significantly between the two groups: SUVmaxpost 6.0 (3.2), SUVmeanpost 3.6 (2.0) and TLG 21751.7 (29794.0). CONCLUSION: In our proof of concept study, combined PET/CT with integrated CTP might show complementary prognostic data pre- and post chemo-radiotherapy. CTP may be used to predict local tumor recurrence, while FDGPET/CT is still needed for whole-body staging.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Imagen Multimodal , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Adulto , Anciano , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/radioterapia , Quimioradioterapia , Terapia Combinada , Femenino , Fluorodesoxiglucosa F18 , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Estudios Prospectivos , Radiofármacos , Tasa de Supervivencia
9.
Eur J Cancer ; 51(18): 2777-84, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26597442

RESUMEN

PURPOSE: Optimum management of the N0 neck is unresolved in oral cancer. Sentinel node biopsy (SNB) can reliably detect microscopic lymph node metastasis. The object of this study was to establish whether the technique was both reliable in staging the N0 neck and a safe oncological procedure in patients with early-stage oral squamous cell carcinoma. METHODS: An European Organisation for Research and Treatment of Cancer-approved prospective, observational study commenced in 2005. Fourteen European centres recruited 415 patients with radiologically staged T1-T2N0 squamous cell carcinoma. SNB was undertaken with an average of 3.2 nodes removed per patient. Patients were excluded if the sentinel node (SN) could not be identified. A positive SN led to a neck dissection within 3 weeks. Analysis was performed at 3-year follow-up. RESULTS: An SN was found in 99.5% of cases. Positive SNs were found in 23% (94 in 415). A false-negative result occurred in 14% (15 in 109) of patients, of whom eight were subsequently rescued by salvage therapy. Recurrence after a positive SNB and subsequent neck dissection occurred in 22 patients, of which 16 (73%) were in the neck and just six patients were rescued. Only minor complications (3%) were reported following SNB. Disease-specific survival was 94%. The sensitivity of SNB was 86% and the negative predictive value 95%. CONCLUSION: These data show that SNB is a reliable and safe oncological technique for staging the clinically N0 neck in patients with T1 and T2 oral cancer. EORTC Protocol 24021: Sentinel Node Biopsy in the Management of Oral and Oropharyngeal Squamous Cell Carcinoma.


Asunto(s)
Carcinoma de Células Escamosas/secundario , Neoplasias de Cabeza y Cuello/patología , Ganglios Linfáticos/patología , Neoplasias de la Boca/patología , Biopsia del Ganglio Linfático Centinela , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/terapia , Quimioradioterapia Adyuvante , Supervivencia sin Enfermedad , Europa (Continente) , Reacciones Falso Negativas , Femenino , Neoplasias de Cabeza y Cuello/mortalidad , Neoplasias de Cabeza y Cuello/terapia , Humanos , Estimación de Kaplan-Meier , Ganglios Linfáticos/cirugía , Metástasis Linfática , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/mortalidad , Neoplasias de la Boca/terapia , Disección del Cuello , Micrometástasis de Neoplasia , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Radioterapia Adyuvante , Factores de Riesgo , Biopsia del Ganglio Linfático Centinela/efectos adversos , Carcinoma de Células Escamosas de Cabeza y Cuello , Factores de Tiempo , Resultado del Tratamiento
10.
Laryngoscope ; 125(8): 1861-8, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25892275

RESUMEN

OBJECTIVE: Follow-up of patients with oral cavity squamous cell carcinoma (OCSCC) after tumor resection and reconstruction with tissue transfer is challenging. We compared contrast-enhanced computed tomography (ceCT), (18) F-fluorodeoxyglucose-positron emission tomography combined with noncontrast enhanced CT ((18) F-FDG-PET/CT), and (18) F-FDG-PET combined with ceCT ((18) F-FDG-PET/ceCT) to determine the accuracy for detection of residual/recurrent disease after flap reconstruction for OCSCC. STUDY DESIGN AND METHODS: Two readers (R1, R2) retrospectively reviewed a total of 27 (18) F-FDG-PET/ceCT scans in patients after resection of stage II to IV OCSCC. They recorded the presence of local persistence/recurrence (LR), lymph node metastasis, or distant metastasis independently for ceCT, (18) F-FDG-PET/CT, and (18) F-FDG-PET/ceCT. Histological workup, imaging follow-up, or clinical follow-up served as the standard of reference. Maximum standardized uptake value (SUVmax) was evaluated to discriminate between physiological uptake and LR. RESULTS: The highest accuracy to detect LR was achieved with (18) F-FDG-PET/ceCT, with a sensitivity/specificity of 88%/89% and 88%/79% for R1 and R2, respectively, as compared to ceCT with 75%/79% for R1 and 88%/68% for R2 and (18) F-FDG-PET/CT with 88%/58% for both R1 and R2. Receiver-operating-characteristic analysis determined a cutoff value for SUVmax of 7.2, yielding a sensitivity and specificity of 75% and 94%, respectively, to distinguish LR from physiological (18) F-FDG uptake. CONCLUSION: (18) F-FDG-PET/ceCT seems to be the most reliable tool for locoregional surveillance of OCSCC patients after resection and reconstruction. LEVEL OF EVIDENCE: 4.


Asunto(s)
Fluorodesoxiglucosa F18 , Neoplasias de la Boca/diagnóstico , Imagen Multimodal , Procedimientos Quirúrgicos Otorrinolaringológicos/métodos , Procedimientos de Cirugía Plástica , Tomografía de Emisión de Positrones/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/secundario , Neoplasias de la Boca/cirugía , Recurrencia Local de Neoplasia/diagnóstico , Periodo Posoperatorio , Curva ROC , Radiofármacos , Estudios Retrospectivos , Colgajos Quirúrgicos
11.
Otolaryngol Head Neck Surg ; 152(1): 165-71, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25385806

RESUMEN

IMPORTANCE: Previous preclinical studies of localized intraoperative virtual endoscopy-image-guided surgery (LIVE-IGS) for skull base surgery suggest a potential clinical benefit. OBJECTIVE: The first aim was to evaluate the registration accuracy of virtual endoscopy based on high-resolution magnetic resonance imaging under clinical conditions. The second aim was to implement and assess real-time proximity alerts for critical structures during skull base drilling. DESIGN AND SETTING: Patients consecutively referred for sinus and skull base surgery were enrolled in this prospective case series. PARTICIPANTS: Five patients were used to check registration accuracy and feasibility with the subsequent 11 patients being treated under LIVE-IGS conditions with presentation to the operating surgeon (phase 2). INTERVENTION: Sixteen skull base patients were endoscopically operated on by using image-based navigation while LIVE-IGS was tested in a clinical setting. MAIN OUTCOME AND MEASURES: Workload was quantitatively assessed using the validated National Aeronautics and Space Administration Task Load Index (NASA-TLX) questionnaire. RESULTS: Real-time localization of the surgical drill was accurate to ~1 to 2 mm in all cases. The use of 3-mm proximity alert zones around the carotid arteries and optic nerve found regular clinical use, as the median minimum distance between the tracked drill and these structures was 1 mm (0.2-3.1 mm) and 0.6 mm (0.2-2.5 mm), respectively. No statistical differences were found in the NASA-TLX indicators for this experienced surgical cohort. CONCLUSIONS AND RELEVANCE: Real-time proximity alerts with virtual endoscopic guidance was sufficiently accurate under clinical conditions. Further clinical evaluation is required to evaluate the potential surgical benefits, particularly for less experienced surgeons or for teaching purposes.


Asunto(s)
Endoscopía , Base del Cráneo/cirugía , Cirugía Asistida por Computador , Adolescente , Adulto , Anciano , Femenino , Humanos , Periodo Intraoperatorio , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Adulto Joven
12.
Head Neck ; 37(10): 1477-82, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24890082

RESUMEN

BACKGROUND: Sentinel lymph node biopsy is a reliable technique for accurate determination of the cervical lymph node status in patients with early oral and oropharyngeal cancer but analyses on the distribution pattern of metastatic spread within sentinel lymph nodes are lacking. METHODS: The localizations of carcinoma deposits were analyzed with a virtual microscope by creating digital images from the microscopic glass slides. RESULTS: Metastatic deposits were not randomly distributed within sentinel lymph nodes but were predominant in the central planes closer to the lymphatic inlet. Initial evaluation of the 4 most central slices achieved a high rate of 90% for the detection of micrometastases and of 80% for the detection of isolated tumor cells (ITCs). CONCLUSION: Based on the distribution we recommend an initial cut through the hilus and to proceed with the 4 most central 150-µm slices. Complete step sectioning is only required in case of a so far negative result.


Asunto(s)
Carcinoma de Células Escamosas/patología , Ganglios Linfáticos/patología , Neoplasias de la Boca/patología , Neoplasias Orofaríngeas/patología , Adulto , Femenino , Humanos , Metástasis Linfática/patología , Masculino , Persona de Mediana Edad , Micrometástasis de Neoplasia , Estadificación de Neoplasias , Estudios Prospectivos , Biopsia del Ganglio Linfático Centinela
13.
Swiss Med Wkly ; 144: w14015, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25255107

RESUMEN

Imaging head and neck cancer is crucial for treatment decisions and follow-up of patients. The choice of the appropriate imaging modality for staging and re-staging head and neck cancer can be troublesome. This review highlights the important questions of imaging from a clinician's perspective. The recommendations focus on mucosal squamous cell carcinoma of the head and neck since this is the most common one.


Asunto(s)
Neoplasias de Cabeza y Cuello/diagnóstico , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Células Escamosas/diagnóstico , Neoplasias de Células Escamosas/patología , Endoscopía , Humanos , Estadificación de Neoplasias , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X
14.
J Nucl Med ; 55(11): 1778-85, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25256060

RESUMEN

UNLABELLED: (D)-(18)F-fluoromethyltyrosine (d-(18)F-FMT), or BAY 86-9596, is a novel (18)F-labeled tyrosine derivative rapidly transported by the l-amino acid transporter (LAT-1), with a faster blood pool clearance than the corresponding l-isomer. The aim of this study was to demonstrate the feasibility of tumor detection in patients with non-small cell lung cancer (NSCLC) or head and neck squamous cell cancer (HNSCC) compared with inflammatory and physiologic tissues in direct comparison to (18)F-FDG. METHODS: 18 patients with biopsy-proven NSCLC (n = 10) or HNSCC (n = 8) were included in this Institutional Review Board-approved, prospective multicenter study. All patients underwent (18)F-FDG PET/CT scans within 21 d before d-(18)F-FMT PET/CT. For all patients, safety and outcome data were assessed. RESULTS: No adverse reactions were observed related to d-(18)F-FMT. Fifty-two lesions were (18)F-FDG-positive, and 42 of those were malignant (34 histologically proven and 8 with clinical reference). Thirty-two of the 42 malignant lesions were also d-(18)F-FMT-positive, and 10 lesions had no tracer uptake above the level of the blood pool. Overall there were 34 true-positive, 8 true-negative, 10 false-negative, and only 2 false-positive lesions for d-(18)F-FMT, whereas (18)F-FDG was true-positive in 42 lesions, with 10 false-positive and only 2 false-negative, resulting in a lesion-based detection rate for d-(18)F-FMT and (18)F-FDG of 77% and 95%, respectively, with an accuracy of 78% for both tracers. A high d-(18)F-FMT tumor-to-blood pool ratio had a negative correlation with overall survival (P = 0.050), whereas the (18)F-FDG tumor-to-blood pool ratio did not correlate with overall survival. CONCLUSION: d-(18)F-FMT imaging in patients with NSCLC and HNSCC is safe and feasible. The presented preliminary results suggest a lower sensitivity but higher specificity for d-(18)F-FMT over (18)F-FDG, since there is no d-(18)F-FMT uptake in inflammation. This increased specificity may be particularly beneficial in areas with endemic granulomatous disease and may improve clinical management. Further clinical investigations are needed to determine its clinical value and relevance for the prediction of survival prognosis.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Células Escamosas/diagnóstico por imagen , Radioisótopos de Flúor/química , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias Pulmonares/diagnóstico por imagen , Tirosina/análogos & derivados , Tirosina/química , Adulto , Anciano , Biopsia , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Reacciones Falso Positivas , Femenino , Fluorodesoxiglucosa F18/química , Neoplasias de Cabeza y Cuello/diagnóstico , Humanos , Inflamación , Estimación de Kaplan-Meier , Neoplasias Pulmonares/diagnóstico , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Pronóstico , Estudios Prospectivos , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X
15.
Head Neck ; 36(6): 828-33, 2014 06.
Artículo en Inglés | MEDLINE | ID: mdl-23720142

RESUMEN

BACKGROUND: The purpose of this study was to evaluate the efficacy of preoperative versus intraoperative mandibular contouring using rapid prototyping technology. METHODS: Ten patients requiring mandibular reconstruction had a preoperative mandibular plate contoured to a fabricated 3D mandibular model based on preoperative imaging. A traditional intraoperative plate was also contoured. Two surgeons blinded to the study compared the plates with respect to conformance, surface-area contact, and best overall match. A cost-benefit analysis was then performed. RESULTS: The average time to contour was 867 ± 243 seconds and 833 ± 289 seconds for the preoperative and intraoperative plates, respectively (p = .83). Interobserver analysis revealed no statistically significant differences in conformance (p = .38) or surface area contact (p = .14). In 7 of 9 cases, the preoperative plate was selected for the final reconstruction. In 1 case, an intraoperative plate was not contoured because of the lateral extent of the tumor. CONCLUSION: In cases of mandibular distortion secondary to disease, pathologic fracture or defects involving multiple mandibular subsites this method is particularly advantageous.


Asunto(s)
Placas Óseas , Periodo Intraoperatorio , Reconstrucción Mandibular , Periodo Preoperatorio , Placas Óseas/economía , Canadá , Análisis Costo-Beneficio , Humanos , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Neoplasias Mandibulares/cirugía , Reconstrucción Mandibular/economía , Reconstrucción Mandibular/métodos , Estudios Prospectivos
16.
Laryngoscope ; 123(12): 2935-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24105632

RESUMEN

OBJECTIVES/HYPOTHESIS: Skull base surgery (SBS) involves operative tasks in close proximity to critical structures in a complex three-dimensional (3D) anatomy. The aim was to investigate the value of virtual planning (VP) based on preoperative magnetic resonance imaging (MRI) for surgical planning in SBS and to compare the effects of virtual planning with 3D contours between the expert and the surgeon in training. STUDY DESIGN: Retrospective analysis. METHODS: Twelve patients with manually segmented anatomical structures based on preoperative MRI were evaluated by eight surgeons in a randomized order using a validated National Aeronautics and Space Administration Task Load Index (NASA-TLX) questionnaire. RESULTS: Multivariate analysis revealed significant reduction of workload when using VP (P<.0001) compared to standard planning. Further, it showed that the experience level of the surgeon had a significant effect on the NASA-TLX differences (P<.05). Additional subanalysis did not reveal any significant findings regarding which type of surgeon benefits the most (P>.05). CONCLUSIONS: Preoperative anatomical segmentation with virtual surgical planning using contours in endoscopic SBS significantly reduces the workload for the expert and the surgeon in training.


Asunto(s)
Endoscopía/educación , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética , Neoplasias de la Base del Cráneo/cirugía , Base del Cráneo/cirugía , Cirugía Asistida por Computador/educación , Interfaz Usuario-Computador , Educación de Postgrado en Medicina , Endoscopía/métodos , Humanos , Estudios Retrospectivos , Neoplasias de la Base del Cráneo/diagnóstico , Cirugía Asistida por Computador/métodos
17.
Laryngoscope ; 123(12): 3043-8, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23754774

RESUMEN

OBJECTIVES/HYPOTHESIS: To identify or confirm any new or suggested independent histopathological predictors in Merkel cell carcinoma (MCC) of the head and neck (HN) correlated with outcome. STUDY DESIGN: Retrospective chart and pathology review. METHODS: Between 1990 and 2010, 58 patients with Merkel cell carcinoma of the head and neck HNMCC were identified for study. Pathologic specimens were reviewed and evaluated for independent prognostic factors and correlated with locoregional recurrence and disease-specific survival. RESULTS: The 2- and 5-year disease-specific survival (DSS) rates were 72.7% and 63.6%, respectively. The local and regional recurrence rates were 12.0% and 24.1%, respectively. A total of 25.9% of the patients developed distant metastases during follow-up. Tumor size (< 1 cm vs. > 1 cm) and the presence of a positive deep resection margin were independently found to be significantly associated with regional recurrence (P = 0.01 and P = 0.04, respectively). No other prognostic factors could be identified. CONCLUSION: Adjuvant radiotherapy cannot remediate a positive resection margin. Given these results, consideration for revision surgery should be considered for a positive deep margin. Frozen section analysis may help to define the margins in this invasive and aggressive disease.


Asunto(s)
Carcinoma de Células de Merkel/patología , Neoplasias de Cabeza y Cuello/patología , Estadificación de Neoplasias , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células de Merkel/mortalidad , Carcinoma de Células de Merkel/terapia , Terapia Combinada , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Neoplasias de Cabeza y Cuello/mortalidad , Neoplasias de Cabeza y Cuello/terapia , Humanos , Masculino , Persona de Mediana Edad , Ontario/epidemiología , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia/tendencias , Resultado del Tratamiento
18.
Laryngoscope ; 123(5): 1210-5, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23426442

RESUMEN

OBJECTIVES/HYPOTHESIS: The aim was to compare the value of 18-Fluoro-Deoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) regarding contralateral lymph node (LN) metastasis in the neck. STUDY DESIGN: Retrospective analysis of 61 patients staged by 18F-FDG-PET/CT. METHODS: Cytology/histology served as a reference standard. Further, metabolic midline invasion (MI) of the primary tumor and the presence of bilateral LN metastases were assessed. RESULTS: A true positive rate in the ipsilateral neck of 80% versus 65% in the contralateral neck was found (P = 0.067). Median-standardized uptake value (SUV)-max for suspicious LN ipsilaterally was 7.6 versus 5.8 contralaterally (P = 0.038). There was no positive correlation between metabolic MI and bilateral metastasis (P = 0.82). CONCLUSIONS: The rate of true positive detected LN by 18F-FDG-PET/CT is less on the contralateral neck side; therefore, all suspicious LNs should be verified by cytology. A high SUV in the contralateral neck suggests metastatic disease regardless of nodal size. Metabolic MI needs to be addressed carefully as it was not predictive for bilateral LN involvement. LEVEL OF EVIDENCE: 4.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico , Fluorodesoxiglucosa F18 , Neoplasias de Cabeza y Cuello/diagnóstico , Imagen Multimodal/métodos , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/secundario , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Neoplasias de Cabeza y Cuello/secundario , Humanos , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/patología , Metástasis Linfática/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Radiofármacos , Reproducibilidad de los Resultados , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello
19.
Cancer Imaging ; 13: 1-7, 2013 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-23425816

RESUMEN

OBJECTIVE: Assess the influence of 2 different patient positions during [18F]fluorodeoxyglucose (FDG) uptake phase on physiologic FDG accumulation of the floor of mouth (FOM) muscles. STUDY DESIGN: A prospective study design was used. METHODS: Two hundred prospectively enrolled patients were included in the study: (a) head and neck cancer (HNC) patients in supine or (b) sitting position, (c) patients with other malignant tumours in supine or (d) sitting position. An intra-individual analysis was done on patients (b) and (d) when such scans were available. Maximum standardized uptake values without correction and corrected for blood pool activity were assessed. RESULTS: The inter-individual analysis (sitting vs supine) revealed no significant differences (P = 0.17 and P = 0.56). The subgroup analysis on the patients with HNC (P = 0.56 and P = 0.15) and in patients with other malignancies (P = 0.14 and P = 0.08) revealed no significant difference; neither did the intra-individual analysis. CONCLUSIONS: The supine or sitting position during the uptake phase for FDG-positron emission tomography/computed tomography has no effect on the amount and distribution of physiologic FDG activity in the muscles of the FOM.


Asunto(s)
Fluorodesoxiglucosa F18 , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Imagen Multimodal/métodos , Músculos/metabolismo , Tomografía de Emisión de Positrones , Radiofármacos , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Suelo de la Boca , Estudios Prospectivos , Posición Supina
20.
Neurosurg Clin N Am ; 24(1): 39-49, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23174356

RESUMEN

Sinonasal carcinomas are uncommon neoplasms accounting for approximately 3% to 5% of all upper respiratory tract malignancies. Sinonasal malignancies in most cases do not cause early symptoms and present in an advanced stage of disease. Exact staging necessitates a clinical and endoscopic examination with biopsy and imaging. Tumor resection using an open or endoscopic approach is usually considered the first treatment option. In general, sinonasal carcinomas are radiosensitive, so adjuvant or neoadjuvant radiation treatment may be indicated in advanced disease. Multidisciplinary surgical and medical oncologic approaches, including ablation and reconstruction, have enhanced the survival outcome over the past few decades.


Asunto(s)
Neoplasias Nasales/terapia , Neoplasias de los Senos Paranasales/terapia , Adenocarcinoma/patología , Carcinoma Adenoide Quístico/patología , Carcinoma Mucoepidermoide/patología , Carcinoma de Células Escamosas/patología , Terapia Combinada , Humanos , Melanoma/patología , Estadificación de Neoplasias , Neuroblastoma/patología , Tumores Neuroendocrinos/patología , Procedimientos Neuroquirúrgicos , Neoplasias Nasales/epidemiología , Neoplasias Nasales/patología , Exposición Profesional/efectos adversos , Neoplasias de los Senos Paranasales/epidemiología , Neoplasias de los Senos Paranasales/patología , Factores de Riesgo
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