BM-BronchoLC - A rich bronchoscopy dataset for anatomical landmarks and lung cancer lesion recognition.

Flexible bronchoscopy has revolutionized respiratory disease diagnosis. It offers direct visualization and detection of airway abnormalities, including lung cancer lesions. Accurate identification of airway lesions during flexible bronchoscopy plays an important role in the lung cancer diagnosis. The application of artificial intelligence (AI) aims to support physicians in recognizing anatomical landmarks and lung cancer lesions within bronchoscopic imagery. This work described the development of BM-BronchoLC, a rich bronchoscopy dataset encompassing 106 lung cancer and 102 non-lung cancer patients. The dataset incorporates detailed localization and categorical annotations for both anatomical landmarks and lesions, meticulously conducted by senior doctors at Bach Mai Hospital, Vietnam. To assess the dataset's quality, we evaluate two prevalent AI backbone models, namely UNet++ and ESFPNet, on the image segmentation and classification tasks with single-task and multi-task learning paradigms. We present BM-BronchoLC as a reference dataset in developing AI models to assist diagnostic accuracy for anatomical landmarks and lung cancer lesions in bronchoscopy data.

Spotting lesions in thorax X-rays at a glance: holistic processing in radiology.

Radiologists often need only a glance to grasp the essence of complex medical images. Here, we use paradigms and manipulations from perceptual learning and expertise fields to elicit mechanisms and limits of holistic processing in radiological expertise. In the first experiment, radiologists were significantly better at categorizing thorax X-rays when they were presented for 200 ms in an upright orientation than when they were presented upside-down. Medical students, in contrast, were guessing in both situations. When the presentation time was increased to 500 ms, allowing for a couple more glances, the radiologists improved their performance on the upright stimuli, but remained at the same level on the inverted presentation. The second experiment circumvented the holistic processing by immediately cueing a tissue within the X-rays, which may or may not contain a nodule. Radiologists were again better than medical students at recognizing whether the cued tissue was a nodule, but this time neither the inverted presentation nor additional time affected their performance. Our study demonstrates that holistic processing is most likely a continuous recurring process which is just as susceptible to the inversion effect as in other expertise domains. More importantly, our study also indicates that holistic-like processing readily occurs in complex stimuli (e.g., whole thorax X-rays) but is more difficult to find in uniform single parts of such stimuli (e.g., nodules).

Craniocervical Posture Assessed With Photogrammetry and the Accuracy of Palpation Methods for Locating the Seventh Cervical Spinous Process: A Cross-sectional Study.

OBJECTIVE: The purpose of this study was to compare craniocervical posture assessed by photogrammetry using 2 distinct palpation methods for locating the spinous process of the seventh cervical vertebra (C7SP). METHODS: This cross-sectional study was conducted in 2 phases. In phase I (n = 42), the assessor's accuracy in locating the C7SP using the flexion-extension and the modified thorax-rib static methods was compared to radiography. In phase II (n = 68), the craniocervical posture was analyzed with photogrammetry after palpation using the 2 methods. Neck pain intensity and disability were also determined. RESULTS: The accuracy in locating the C7SP was higher using the modified thorax-rib static method (67%, 95% confidence interval [CI], 55-79) compared to the flexion-extension method (38%, 95% CI, 26-50, P = .016). Lower values of the craniocervical angle were obtained with the flexion-extension method than the modified thorax-rib static method (mean difference = -1.1°, 95% CI, -1.6 to -0.6, P < .001). However, both palpation methods resulted in similar classifications of participants as with or without forward head posture (P = .096). Weak correlations were observed between the craniocervical angle and neck pain intensity (ρ = -0.088 and -0.099, respectively) and disability (ρ = -0.231 and -0.249, respectively). CONCLUSION: Craniocervical angles obtained using palpation methods with different accuracies were different, although the magnitude of the difference was insufficient to lead to different classifications of a forward head posture in adults with mild neck pain and disability. Craniocervical posture was weakly correlated with neck-pain intensity and disability.

Efficacy and safety of Chinese herbal medicine versus Lopinavir-Ritonavir in adult patients with coronavirus disease 2019: A non-randomized controlled trial.

BACKGROUND: Treatments for coronavirus disease 2019 (COVID-19) are limited by suboptimal efficacy. METHODS: From January 30, 2020 to March 23, 2020, we conducted a non-randomised controlled trial, in which all adult patients with laboratory-confirmed COVID-19 were assigned to three groups non-randomly and given supportive treatments: Group A, Lopinavir-Ritonavir; Group B, Huashi Baidu Formula (a Chinese medicineformula made by the China Academy of Chinese Medical Sciences to treat COVID-19, which is now in the clinical trial period) and Lopinavir-Ritonavir; and Group C, Huashi Baidu Formula. The use of antibiotics, antiviruses, and corticosteroids was permitted in Group A and B. Traditional Chinese medicine injections were permitted in Group C. The primary outcomes were clinical remission time (interval from admission to the first time the patient tested negatively for novel coronavirus or an obvious improvement was observed from chest CT) and clinical remission rate (number of patients whose clinical time was within 16 days/total number of patients). RESULTS: A total of 60 adult patients with COVID-19 were enrolled at sites in Wuhan, China, and the sample size of each group was 20. In Groups A, B and C, the clinical remission rates were 95.0%%(19/20), 100.0%%(20/20) and 100.0%%(20/20), respectively. Compared with Groups A and B, the clinical remission time of Group C was significantly shorter (5.9 days vs. 10.8 days, p < 0.05; 5.9 days vs. 9.7 days, p < 0.05). There was no significant difference among Groups A, B, and C in terms of the time taken to be released from quarantine. The clinical biochemical indicators and safety indexes showed no significant differences among the three groups. CONCLUSIONS: Our findings suggest that Lopinavir-Ritonavir has some efficacy in the treatment of COVID-19, and the Huashi Baidu Formula might enhance this effect to an extent. In addition, superiority was displayed in the treatment of COVID-19 through a combination of the Huashi Baidu Formula and traditional Chinese medicine injection. In future, well-designed prospective double-blinded randomised control trials are required to confirm our findings.

Afectación respiratoria por coronavirus (COVID-19) / Respiratory involvement by coronavirus (COVID-19)

In December 2019, an epidemic of cases with unexplained lower respiratory infections detected in Wuhan, China was first reported to the WHO China Office. The respiratory picture presents in various ways, from asymptomatic or paucisymptomatic forms, to clinical conditions characterized by respiratory failure that require mechanical ventilation and support in the ICU, with multi-organ and systemic manifestations in terms of sepsis, septic shock and multiple organ dysfunction syndromes. The etiological agent was identified as a virus belonging to the coronavirus family (CoV) with a high contagion capacity that determined its rapid spread, triggering a pandemic with high morbidity and mortality. This review attempts to address the basics of this disease.

Deep Learning for Automatic Calcium Scoring in CT: Validation Using Multiple Cardiac CT and Chest CT Protocols.

Background Although several deep learning (DL) calcium scoring methods have achieved excellent performance for specific CT protocols, their performance in a range of CT examination types is unknown. Purpose To evaluate the performance of a DL method for automatic calcium scoring across a wide range of CT examination types and to investigate whether the method can adapt to different types of CT examinations when representative images are added to the existing training data set. Materials and Methods The study included 7240 participants who underwent various types of nonenhanced CT examinations that included the heart: coronary artery calcium (CAC) scoring CT, diagnostic CT of the chest, PET attenuation correction CT, radiation therapy treatment planning CT, CAC screening CT, and low-dose CT of the chest. CAC and thoracic aorta calcification (TAC) were quantified using a convolutional neural network trained with (a) 1181 low-dose chest CT examinations (baseline), (b) a small set of examinations of the respective type supplemented to the baseline (data specific), and (c) a combination of examinations of all available types (combined). Supplemental training sets contained 199-568 CT images depending on the calcium burden of each population. The DL algorithm performance was evaluated with intraclass correlation coefficients (ICCs) between DL and manual (Agatston) CAC and (volume) TAC scoring and with linearly weighted κ values for cardiovascular risk categories (Agatston score; cardiovascular disease risk categories: 0, 1-10, 11-100, 101-400, >400). Results At baseline, the DL algorithm yielded ICCs of 0.79-0.97 for CAC and 0.66-0.98 for TAC across the range of different types of CT examinations. ICCs improved to 0.84-0.99 (CAC) and 0.92-0.99 (TAC) for CT protocol-specific training and to 0.85-0.99 (CAC) and 0.96-0.99 (TAC) for combined training. For assignment of cardiovascular disease risk category, the κ value for all test CT scans was 0.90 (95% confidence interval [CI]: 0.89, 0.91) for the baseline training. It increased to 0.92 (95% CI: 0.91, 0.93) for both data-specific and combined training. Conclusion A deep learning calcium scoring algorithm for quantification of coronary and thoracic calcium was robust, despite substantial differences in CT protocol and variations in subject population. Augmenting the algorithm training with CT protocol-specific images further improved algorithm performance. © RSNA, 2020 See also the editorial by Vannier in this issue.

Simplified Statistical Image Reconstruction for X-ray CT With Beam-Hardening Artifact Compensation.

CT images are often affected by beam-hardening artifacts due to the polychromatic nature of the X-ray spectra. These artifacts appear in the image as cupping in homogeneous areas and as dark bands between dense regions such as bones. This paper proposes a simplified statistical reconstruction method for X-ray CT based on Poisson statistics that accounts for the non-linearities caused by beam hardening. The main advantages of the proposed method over previous algorithms are that it avoids the preliminary segmentation step, which can be tricky, especially for low-dose scans, and it does not require knowledge of the whole source spectrum, which is often unknown. Each voxel attenuation is modeled as a mixture of bone and soft tissue by defining density-dependent tissue fractions and maintaining one unknown per voxel. We approximate the energy-dependent attenuation corresponding to different combinations of bone and soft tissues, the so-called beam-hardening function, with the 1D function corresponding to water plus two parameters that can be tuned empirically. Results on both simulated data with Poisson sinogram noise and two rodent studies acquired with the ARGUS/CT system showed a beam hardening reduction (both cupping and dark bands) similar to analytical reconstruction followed by post-processing techniques but with reduced noise and streaks in cases with a low number of projections, as expected for statistical image reconstruction.

Chest Radiographs for Distinguishing ADA-SCID from Other Forms of SCID.

PURPOSE: Early differentiation of adenosine deaminase deficient severe combined immunodeficiency (ADA-SCID) from other forms of SCID may initiate appropriate treatment interventions with the aim of metabolic detoxification and improved outcome. Our hypothesis was that previously described radiological features (inferior scapular angle squaring and spurring and costochondral cupping) can differentiate ADA-SCID from other forms of SCID. METHODS: Chest radiographs at clinical presentation between 2000 and 2017 of children with ADA-SCID were retrospectively included, provided that the radiological features were assessable. Random chest radiographs of children with other forms of SCID were included for comparison. Three paediatric radiologists (2 senior, 1 junior) assessed the radiographs for the specific radiological features and stated their diagnosis (ADA-SCID or non-ADA-SCID). An optimal threshold for test performance was defined using a ROC curve. RESULTS: Thirty-six patients with ADA-SCID and twenty-five patients with non-ADA-SCID were included (median age 3.8 months). The optimal threshold for test performance was at approximately < 7 months old: sensitivity 91.7%, specificity 80.7%, interreader agreement was k = 0.709, AUC 0.862. The positive likelihood ratio for scapular squaring, scapular spur, and costochondral cupping was 4.0, 54.6 and 7.8, respectively. The test was valid when performed by both senior and junior paediatric radiologists. CONCLUSION: Radiological features such as scapular spurring, scapular squaring and costochondral cupping can reliably differentiate between ADA-SCID and other forms of SCID. This is true for children aged approximately < 7 months, and this is reliable when assessed by both senior and junior paediatric radiologists.

Mycobacterium abscessus subsp. abscessus empyema complicated with subcutaneous abscess.

There have been no case reports of thoracic subcutaneous abscess after surgery for Mycobacterium abscessus complex associated empyema. We herein report a case of Mycobacterium abscessus subsp. abscessus (M. abscessus subsp. abscessus) induced subcutaneous abscesses following surgical treatment for concurrent M. abscessus subsp. abscessus -associated empyema and pneumothorax. A 75-year-old woman had M. abscessus subsp. abscessus -associated empyema and pneumothorax. She underwent surgical treatment of decortication and fistulectomy and suffered from M. abscessus subsp. abscessus -associated subcutaneous abscesses after thoracentesis/drainage. A multidisciplinary approach combined with surgical care, thermal therapy, and multidrug chemotherapy contributed to a successful result. An early multidisciplinary approach is believed to be important in cases of M. abscessus subsp. abscessus -associated empyema and subcutaneous abscess.

Bloqueos de tronco / Truncal blocks

Truncal blocks have recently been positioned as an alternative to neuraxial analgesia. The injection of local anesthetics in interfascial planes was initially guided by anatomical landmarks, to later evolve towards a more selective administration when guided by ultrasound. Successful execution of truncal blocks requires detailed knowledge of the chest and abdominal walls anatomy. The same logic allows us to understand its potential benefits concerning perioperative analgesia, as well as its limitations and therapeutic margins. Secondary to a growing interest in less invasive techniques and analgesic techniques with a more favorable risk-benefit profile, the available evidence in this field is in continuous development. Thus, in the present review, the technical aspects of these blocks will be evaluated, emphasizing the sonoanatomy, and assessing the best evidence to support the use of each technique.

Los bloqueos de tronco se han posicionado recientemente como una alternativa frente a la analgesia neuroaxial. La inyección de anestésicos locales en planos interfasciales inicialmente fue guiado por referencias anatómicas, para posteriormente evolucionar hacia una administración más selectiva al ser guiada por el ultrasonido. La ejecución exitosa de los bloqueos de tronco requiere un conocimiento detallado de la anatomía de las paredes del tórax y abdomen. Esta misma lógica nos permite entender sus potenciales beneficios en relación con la analgesia perioperatoria, como también sus limitaciones y margen terapéutico. La evidencia disponible está en continuo desarrollo, dado el creciente interés que concitan técnicas menos invasivas y con un perfil de riesgo-beneficio potencialmente más favorable. En la presente revisión se evaluarán los aspectos técnicos de cada bloqueo, poniendo énfasis en la sonoanatomía, y evaluando la mejor evidencia que sustente el uso de cada técnica.

A 60-Year-Old Woman With Acute Chest Pain and Bilateral Pleural and Pericardial Effusions.

CASE PRESENTATION: A 60-year-old woman presented with acute-onset, progressively worsening shortness of breath and pleuritic chest pain for 3 days. She also complained of a dry cough, but no fever or chills. There was no history of swelling of the feet; nor was there a history of nausea or diarrhea. She was a lifelong nonsmoker and had no history of recent travel or sick contacts. Her medical history included hypertension and ulcerative colitis. The ulcerative colitis was in remission and she had not been taking medications for this for over 7 years. Her home medications included alendronate, amlodipine, aspirin, atenolol, and vitamin D3 supplements. She had no allergies.

Geometry and energy constrained projection extension.

BACKGROUND: In clinical computed tomography (CT) applications, when a patient is obese or improperly positioned, the final tomographic scan is often partially truncated. Images directly reconstructed by the conventional reconstruction algorithms suffer from severe cupping and direct current bias artifacts. Moreover, the current methods for projection extension have limitations that preclude incorporation from clinical workflows, such as prohibitive computational time for iterative reconstruction, extra radiation dose, hardware modification, etc.METHOD:In this study, we first established a geometrical constraint and estimated the patient habitus using a modified scout configuration. Then, we established an energy constraint using the integral invariance of fan-beam projections. Two constraints were extracted from the existing CT scan process with minimal modification to the clinical workflows. Finally, we developed a novel dual-constraint based optimization model that can be rapidly solved for projection extrapolation and accurate local reconstruction. RESULTS: Both numerical phantom and realistic patient image simulations were performed, and the results confirmed the effectiveness of our proposed approach. CONCLUSION: We establish a dual-constraint-based optimization model and correspondingly develop an accurate extrapolation method for partially truncated projections. The proposed method can be readily integrated into the clinical workflow and efficiently solved by using a one-dimensional optimization algorithm. Moreover, it is robust for noisy cases with various truncations and can be further accelerated by GPU based parallel computing.

Tumor evanescente: un reto diagnóstico / Evanescent tumour: a diagnostic challenge

Resumen El tumor fantasma es una efusión interlobal pulmonar, interpretada como una manifestación radiológica poco común en personas con falla cardíaca descompensada; una vez se establece el tratamiento, estas lesiones que inicialmente se pueden confundir con infecciones o lesiones tumorales, desaparecen, por lo cual es fundamental realizar un diagnóstico adecuado que evite la práctica de estudios invasivos y no invasivos. Se expone el caso de un hombre con antecedente de falla cardíaca congestiva, quien ingresó al servicio de urgencias por exacerbación de síntomas respiratorios, edemas de miembros inferiores, disnea paroxística nocturna, ortopnea y signos clínicos de falla cardíaca. La radiografía de tórax mostró cardiomegalia, engrosamiento pleural derecho periférico y dos imágenes de tipo masa en tercios medio e inferior derechos y opacidad intersticial en bases. Se estableció manejo médico para falla cardíaca y se ordenó radiografía de tórax tres días después del tratamiento, luego de lo cual se observó desaparición de lesión intrapulmonar, confirmando diagnóstico de tumor fantasma.

Abstract The phantom (evanescent) tumour is an interlobar lung effusion, interpreted as a rare radiological sign in individuals with decompensated heart failure. Once the treatment is established, these lesions, which initially can be confused with infections or tumour lesions, disappear. This makes it essential to make an appropriate diagnosis that avoids carrying out invasive and non-invasive studies. The case is presented of a man with a history of congestive heart failure, who was admitted to the Emergency Department due to the exacerbation of respiratory symptoms, swelling in the legs, paroxysmal nocturnal dyspnoea, orthopnoea, and clinical signs of heart failure. The chest x-ray showed cardiomegaly, right pleural peripheral thickening, and two mass-type images in the right middle and lower thirds, as well as interstitial opacity in the bases. Medical management for heart failure was established, and a chest x-ray was requested three days after the treatment, in which it was observed that the intra-pulmonary lesion had disappeared, confirming the diagnosis of a phantom tumour.

Early detection of lung cancer using ultra-low-dose computed tomography in coronary CT angiography scans among patients with suspected coronary heart disease.

OBJECTIVES: To assess whether an additional chest ultra-low-dose CT scan to the coronary CT angiography protocol can be used for lung cancer screening among patients with suspected coronary artery disease. METHODS: 175 patients underwent coronary CT angiography for assessment of coronary artery disease, additionally undergoing ultra-low-dose CT screening to early diagnosis of lung cancer in the same scanner (80kVp and 15mAs). Patients presenting pulmonary nodules were followed-up for two years, repeating low-dose CTs in intervals of 3, 6, or 12 months based on nodule size and growth rate in accordance with National Comprehensive Cancer Network guidelines. RESULTS: Ultra-low-dose CT identified 71 patients with solitary pulmonary nodules (41%), with a mean diameter of 5.50±4.00mm. Twenty-eight were >6mm, and in 79% (n=22) of these cases they were false positive findings, further confirmed by follow-up (n=20), resection (n=1), or biopsy (n=1). Lung cancer was detected in six patients due to CT screening (diagnostic yield: 3%). Among these, four cases could not be detected in the cardiac field of view. Most patients were in early stages of the disease. Two patients diagnosed at advanced stages died due to cancer complications. The addition of the ultra-low-dose CT scan represented a radiation dose increment of 1.22±0.53% (effective dose, 0.11±0.03mSv). CONCLUSIONS: Lung cancer might be detected using additional ultra-low-dose protocols in coronary CT angiography scans among patients with suspected coronary artery disease.

Locating the Seventh Cervical Spinous Process: Accuracy of the Thorax-Rib Static Method and the Effects of Clinical Data on Its Performance.

OBJECTIVES: The aim of this study was to assess the thorax-rib static method (TRSM), a palpation method for locating the seventh cervical spinous process (C7SP), and to report clinical data on the accuracy of this method and that of the neck flexion-extension method (FEM), using radiography as the gold standard. METHODS: A single-blinded, cross-sectional diagnostic accuracy study was conducted. One hundred and one participants from a primary-to-tertiary health care center (63 men, 56 ± 17 years of age) had their neck palpated using the FEM and the TRSM. A single examiner performed both the FEM and TRSM in a random sequence. Radiopaque markers were placed at each location with the aid of an ultraviolet lamp. Participants underwent chest radiography for assessment of the superimposed inner body structure, which was located by using either the FEM or the TRSM. RESULTS: Accuracy in identifying the C7SP was 18% and 33% (P = .013) with use of the FEM and the TRSM, respectively. The cumulative accuracy considering both caudal and cephalic directions (C7SP ± 1SP) increased to 58% and 81% (P = .001) with use of the FEM and the TRSM, respectively. Age had a significant effect on the accuracy of FEM (P = .027) but not on the accuracy of TRSM (P = .939). Sex, body mass, body height, and body mass index had no significant effects on the accuracy of both the FEM (P = .209 or higher) and the TRSM (P = .265 or higher). CONCLUSIONS: The TRMS located the C7SP more accurately compared with the FEM at any given level of anatomic detail, although both still underperformed in terms of acceptable accuracy for a clinical setting.

Stranded seed displacement, migration, and loss after permanent prostate brachytherapy as estimated by Day 0 fluoroscopy and 4-month postimplant pelvic x-ray.

PURPOSE: The aim of the study was to determine the incidence of local displacement, distant seed migration to the chest, and seed loss after permanent prostate brachytherapy (PPB) with stranded seeds (SSs) using sequential two-dimensional fluoroscopic pelvic and chest x-rays. METHODS AND MATERIALS: Between October 2010 and April 2014, a total of 137 patients underwent PPB and 4-month followup pelvic and chest x-ray imaging. All patients had exclusively SSs placed and an immediate postimplant fluoroscopic image of the seed cluster. Followup x-ray images were evaluated for the number, location, and displacement of seeds in comparison to Day 0 fluoroscopic images. Significant seed displacement was defined as seed displacement >1 cm from the seed cluster. Followup chest x-rays were evaluated for seed migration to the chest. RESULTS: Seed migration to the chest occurred in 3 of the 137 patients (2%). Seed loss occurred in 38 of the 137 patients (28%), with median loss of one seed (range, 1-16), and total seeds loss of 104 of 10,088 (1.0%) implanted. Local seed displacement was seen in 12 of the 137 patients (8.8%), and total seeds displaced were 0.15% (15/10,088). CONCLUSIONS: SS placement in PPB is associated with low rates of substantial seed loss, local displacement, or migration to the chest. Comparing immediate postimplant fluoroscopic images to followup plain x-ray images is a straightforward method to supplement quality assurance in PPB and was found to be useful in identifying cases where seed loss was potentially of clinical significance.

Fluorocholine PET/computed tomography: physiologic uptake, benign findings, and pitfalls.

Choline PET has a role in the diagnosis of malignancies. Knowledge of normal biodistribution plays a vital role in disease characterization and in differentiating normal variants from disease processes. CT and MR scans provide complementary information, and choline-positive sites should be correlated clinically to exclude inflammatory disorders.

[Transthoracal puncture biopsy under ultrasonic induction in tumors of the anterior mediastinum].

Differential diagnostics of tumors of anterior mediastinum is one of the most difficult problems of thoracic surgery and oncology. The authors conducted a retrospective analysis of the results of transthoracal puncture biopsy under ultrasonic induction in 44 patients with the tumors of the anterior mediastinum. Transthoracal biopsy was carried out using the device for biopsy (Multiple Biopsy Device-MBD-23) and ultrasonic scanner (Voluson 730 Expert), the patients being under intravenous (38 patients) and under local (6 patients) anesthetization. The diagnosis was made as a result of morphological research in all 100% of patients, the biopsy being performed the second time in one patient. The general information value of puncture biopsy under ultrasonic induction was 98%. A complication (localized pneumothorax, cupping off by itself) took place only in one of the follow-up study (2%). The analysis of presented material let the authors make a conclusion that transthoracal puncture biopsy under ultrasonic induction is a safe and highly informative method of diagnostics of tumors of the anterior mediastinum in selected patients.

Dose recalculation in megavoltage cone-beam CT for treatment evaluation: removal of cupping and truncation artefacts in scans of the thorax and abdomen.

PURPOSE: To correct megavoltage cone-beam CT (MVCBCT) images of the thorax and abdomen for cupping and truncation artefacts to reconstruct the 3D-delivered dose distribution for treatment evaluation. MATERIALS AND METHODS: MVCBCT scans of three phantoms, three lung and two rectal cancer patients were acquired. The cone-beam projection images were iteratively corrected for cupping and truncation artefacts and the resulting primary transmission was used for cone-beam reconstruction. The reconstructed scans were merged into the planning CT scan (MVCBCT+). Dose distributions of clinical IMRT, stereotactic and conformal treatment plans were recalculated on the uncorrected and corrected MVCBCT+ scans using the treatment planning system and compared to the planned dose distribution. RESULTS: The dose distributions on the corrected MVCBCT+ of the phantoms were accurate for 99% of the voxels within 2% or 2mm. Using this method the errors in mean GTV dose reduced from about 10% to 1% for the patients. CONCLUSIONS: The method corrects cupping and truncation artefacts in cone-beam scans of the thorax and abdomen in addition to head-and-neck (demonstrated previously). The corrected scans can be used to calculate the influence of anatomical changes on the 3D-delivered dose distribution.

Clinical relevance of single-photon emission computed tomography/computed tomography of the neck and thorax in postablation (131)I scintigraphy for thyroid cancer.

CONTEXT: In patients with differentiated thyroid carcinoma, postablation (131)I scintigraphy aims to detect residual neck disease and distant metastases, usually found in lungs and bones. New hybrid single-photon emission computed tomography/computed tomography (SPECT-CT) cameras that permit functional and anatomical image fusion may improve its clinical relevance. OBJECTIVE: Our objective was to test the added value of neck and thorax SPECT-spiral CT to whole-body scan (WBS) in postablation (131)I scintigraphy. DESIGN AND SETTING: This was a single-referral-center prospective study with a median follow-up of 21 months. PATIENTS AND METHODS: Postablation (131)I WBS and neck and thorax SPECT-CT were performed in 55 consecutive patients treated in 2006. WBS and SPECT-CT data were blindly reviewed, scored negative (benign), positive (malignant), or indeterminate and were correlated to the patient outcome. RESULTS: At patient level, WBS and SPECT-CT were negative in 67 and 78% of patients, positive in 4 and 15%, and indeterminate in 29 and 7%, respectively. Overall, nine patients (16%) presented treatment failure (persistent or recurrent disease) 1-16 months after radioiodine ablation. In the 16 patients with indeterminate WBS, negative SPECT-CT ruled out suspicion of disease in nine of nine patients, and positive SPECT-CT confirmed malignant lesions in four of five patients. Positive SPECT-CT predicted treatment failure better than positive WBS (McNemar's test, P = 0.03). CONCLUSIONS: This study demonstrates the complementary role of neck and thorax SPECT-CT to WBS in postablation (131)I scintigraphy. Because SPECT-CT allows one to confirm or to rule out residual disease in most cases where WBS remains indeterminate, we recommend its use when available.