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1.
Cancers (Basel) ; 15(23)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38067372

RESUMO

Surgical resection remains the gold standard of treatment for early-stage lung cancer. Several risk models exist to predict postoperative morbidity and mortality. Psoas muscle sarcopenia has already successfully been used for morbidity prediction in lung transplantation and is not yet included in the available risk scores for pulmonary resections. We hypothesized that the skeletal muscle index and mediastinal adipose tissue might also have an impact on postoperative outcomes after primary surgery for primary lung cancer. The institutional database was queried for patients with primary lung cancer who were treated with primary lobectomy or segmentectomy between February 2009 and November 2018. In total, 311 patients were included for analysis. Patients receiving neo-/adjuvant chemotherapy or with a positive nodal status were excluded to rule out any morbidity or mortality due to (neo-)adjuvant treatment. Sarcopenia was defined as a skeletal muscle index of <34.4 cm2/m2 for women and <45.4 cm2/m2 for men. Mediastinal adipose tissue was defined with a radiodensity of -150 to -30 Hounsfield units. Sarcopenia was diagnosed in 78 (25.1%) of the 311 patients. Male patients were significantly more likely to suffer from sarcopenia (31.5% vs. 18.1%, p = 0.009). Comorbidities, lung function, tumour histology, pathologic tumour staging, mediastinal adipose tissue and age did not differ between groups with or without sarcopenia. Sarcopenic patients had a significantly longer length of stay, with 13.0 days vs. 9.5 (p = 0.003), and a higher rate of any postoperative complications (59.0% vs. 44.6%, p = 0.036). There was no difference in recurrence rate. Five-year overall survival was significantly better in the patient cohort without sarcopenia (75.6% vs. 64.5%, p = 0.044). Mediastinal adipose tissue showed no significant impact on length of stay, postoperative complications, recurrence rate, morbidity or survival. Sarcopenia, quantified with the skeletal muscle index, is shown to be a risk factor for postoperative morbidity and reduced survival in primary lung cancer. Efforts should be taken to pre-emptively screen for sarcopenia and start countermeasures (e.g., physical prehabilitation, protein-rich nutrition, etc.) during the preoperative workup phase.

2.
Imaging Sci Dent ; 53(1): 69-75, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37006794

RESUMO

Purpose: Maxillofacial trauma predominantly affects young adults between 20 and 40 years of age. Although radioprotection is a legal requirement, the significant potential of dose reduction in computed tomography (CT) is still underused in the clinical routine. The objective of this study was to evaluate whether maxillofacial fractures can be reliably detected and classified using ultra-low-dose CT. Materials and Methods: CT images of 123 clinical cases with maxillofacial fractures were classified by two readers using the AOCOIAC software and compared with the corresponding results from post-treatment images. In group 1, consisting of 97 patients with isolated facial trauma, pre-treatment CT images at different dose levels (volumetric computed tomography dose index: ultra-low dose, 2.6 mGy; low dose, <10 mGy; and regular dose, <20 mGy) were compared with post-treatment cone-beam computed tomography (CBCT). In group 2, consisting of 31 patients with complex midface fractures, pre-treatment shock room CT images were compared with post-treatment CT at different dose levels or CBCT. All images were presented in random order and classified by 2 readers blinded to the clinical results. All cases with an unequal classification were re-evaluated. Results: In both groups, ultra-low-dose CT had no clinically relevant effect on fracture classification. Fourteen cases in group 2 showed minor differences in the classification code, which were no longer obvious after comparing the images directly to each other. Conclusion: Ultra-low-dose CT images allowed the correct diagnosis and classification of maxillofacial fractures. These results might lead to a substantial reconsideration of current reference dose levels.

3.
Diagnostics (Basel) ; 11(9)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34574008

RESUMO

BACKGROUND: Stress hyperglycemia is common in trauma patients. Increasing injury severity and hemorrhage trigger hepatic gluconeogenesis, glycogenolysis, peripheral and hepatic insulin resistance. Consequently, we expect glucose levels to rise with injury severity in liver, kidney and spleen injuries. In contrast, we hypothesized that in the most severe form of blunt liver injury, stress hyperglycemia may be absent despite critical injury and hemorrhage. METHODS: All patients with documented liver, kidney or spleen injuries, treated at a university hospital between 2000 and 2020 were charted. Demographic, laboratory, radiological, surgical and other data were analyzed. RESULTS: A total of 772 patients were included. In liver (n = 456), spleen (n = 375) and kidney (n = 152) trauma, an increase in injury severity past moderate to severe (according to the American Association for the Surgery of Trauma, AAST III-IV) was associated with a concomitant rise in blood glucose levels independent of the affected organ. While stress-induced hyperglycemia was even more pronounced in the most severe forms (AAST V) of spleen (median 10.7 mmol/L, p < 0.0001) and kidney injuries (median 10.6 mmol/L, p = 0.004), it was absent in AAST V liver injuries, where median blood glucose level even fell (5.6 mmol/L, p < 0.0001). CONCLUSIONS: Absence of stress hyperglycemia on hospital admission could be a sign of most severe liver injury (AAST V). Blood glucose should be considered an additional diagnostic criterion for grading liver injury.

4.
Eur J Cardiothorac Surg ; 61(1): 75-82, 2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-34263302

RESUMO

OBJECTIVES: Since the introduction of the minimally invasive technique for repair of pectus excavatum (MIRPE), increasing numbers of patients are presenting for surgery. However, controversy remains regarding cardiopulmonary outcomes of surgical repair. Therefore, the aim of our prospective study was to investigate cardiopulmonary function, at rest and during exercise before surgery, first after MIRPE and then after pectus bar removal. METHODS: Forty-seven patients were enrolled in a prospective, open-label, single-arm, single-centre clinical trial (Impact of Surgical Treatments of Thoracic Deformation on Cardiopulmonary Function) [NCT02163265] between July 2013 and November 2019. All patients underwent a modified MIRPE technique for surgical correction of pectus excavatum (PE), called Minor Open Videoendoscopically Assisted Repair of Pectus Excavatum. The patients underwent pre- and postoperative chest X-ray, three-dimensional volume-rendering computer tomography thorax imaging, cardiopulmonary function tests at rest and during stepwise cycle spiroergometry (sitting and supine position) and Doppler echocardiography. Daily physical activity questionnaires were also completed. RESULTS: The study was completed by 19 patients (15 males, 4 females), aged 13.9-19.6 years at the time of surgery. The surgical patient follow-up was 5.7 ± 7.9 months after pectus bar removal. No significant differences in cardiopulmonary and exercise parameters were seen after placement of the intrathoracic bar, or after pectus bar removal, compared to presurgery. CONCLUSIONS: Our findings indicate that surgical correction of PE does not impair cardiopulmonary function at rest or during exercise. Therefore, no adverse effects on exercise performance should be expected from surgical treatment of PE via the modified MIRPE technique. CLINICAL TRIAL REGISTRATION NUMBER: clinicaltrials.gov [ClinicalTrials.gov number, NCT02163265].


Assuntos
Tórax em Funil , Toracoplastia , Adolescente , Adulto , Feminino , Tórax em Funil/cirurgia , Humanos , Masculino , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Período Pós-Operatório , Estudos Prospectivos , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
5.
Eur J Cardiothorac Surg ; 59(2): 382-388, 2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33212487

RESUMO

OBJECTIVES: The frequency of sternochondroplasty in cases of pectus carinatum (PC) has increased due to greater surgeon experience and modified surgical techniques. PC deformity does not usually cause cardiopulmonary malfunction or impairment. However, whether cardiopulmonary function changes after surgical repair remains a matter of controversy. The aim of our prospective study was to determine if surgery changes preoperative cardiopulmonary function. METHODS: Nineteen patients (16 males, 3 females) were enrolled in a prospective, open-label, single-arm, single-centre clinical trial (Impact of Surgical Treatments of Thoracic Deformation on Cardiopulmonary Function) (NCT02163265) between July 2013 and January 2017. All patients underwent PC repair via a modified Ravitch procedure and wore a lightweight, patient-controlled chest brace for 8 weeks postoperatively (the Innsbruck protocol). The average follow-up surgical examination was 8.3 months after surgery. In all enrolled patients, before surgery and not before 6 months postoperatively chest X-ray, 3-dimensional volume-rendered computed tomography thorax imaging, cardiopulmonary function tests with stepwise cycle spiroergometry (sitting and supine position) and Doppler echocardiography were performed; questionnaires about daily physical activity were also completed. RESULTS: Fourteen patients (aged 16.3 ± 2.6 years at study entry) completed the study. Changes in submaximal and peak power output were not detected during sitting, or when in the supine position. Also, no clinically relevant postoperative changes in spirometry or echocardiography were noted. CONCLUSIONS: Our findings confirm that surgical correction of PC does not impair cardiopulmonary function at rest or during physical exercise. CLINICAL REGISTRATION NUMBER: clinicaltrials.gov NCT02163265.


Assuntos
Tórax em Funil , Pectus Carinatum , Feminino , Humanos , Masculino , Pectus Carinatum/cirurgia , Estudos Prospectivos , Tórax , Resultado do Tratamento
6.
Eur Radiol ; 30(12): 6570-6581, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32696255

RESUMO

OBJECTIVES: Non-operative management (NOM) is increasingly utilised in blunt abdominal trauma. The 1994 American Association of Surgery of Trauma grading (1994-AAST) is applied for clinical decision-making in many institutions. Recently, classifications incorporating contrast extravasation such as the CT severity index (CTSI) and 2018 update of the liver and spleen AAST were proposed to predict outcome and guide treatment, but validation is pending. METHODS: CT images of patients admitted 2000-2016 with blunt splenic and hepatic injury were systematically re-evaluated for 1994/2018-AAST and CTSI grading. Diagnostic accuracy, diagnostic odds ratio (DOR), and positive and negative predictive values were calculated for prediction of in-hospital mortality. Correlation with treatment strategy was assessed by Cramer V statistics. RESULTS: Seven hundred and three patients were analysed, 271 with splenic, 352 with hepatic and 80 with hepatosplenic injury. Primary NOM was applied in 83% of patients; mortality was 4.8%. Comparing prediction of mortality in mild and severe splenic injuries, the CTSI (3.1% vs. 10.3%; diagnostic accuracy = 75.4%; DOR = 3.66; p = 0.006) and 1994-AAST (3.3% vs. 10.5%; diagnostic accuracy = 77.9%; DOR = 3.45; p = 0.010) were more accurate compared with the 2018-AAST (3.4% vs. 8%; diagnostic accuracy = 68.2%; DOR = 2.50; p = 0.059). In hepatic injuries, the CTSI was superior to both AAST classifications in terms of diagnostic accuracy (88.7% vs. 77.1% and 77.3%, respectively). CTSI and 2018-AAST correlated better with the need for surgery in severe vs. mild hepatic (Cramer V = 0.464 and 0.498) and splenic injuries (Cramer V = 0.273 and 0.293) compared with 1994-AAST (Cramer V = 0.389 and 0.255; all p < 0.001). CONCLUSIONS: The 2018-AAST and CTSI are superior to the 1994-AAST in correlation with operative treatment in splenic and hepatic trauma. The CTSI outperforms the 2018-AAST in mortality prediction. KEY POINTS: • Non-operative management of blunt abdominal trauma is increasingly applied and correct patient stratification is crucial. • CT-based scoring systems are used to assess injury severity and guide clinical decision-making, whereby the 1994 version of the American Association of Surgery of Trauma Organ Injury Scale (AAST-OIS) is currently most commonly utilised. • Including contrast media extravasation in CT-based grading improves management and outcome prediction. While the 2018-AAST classification and the CT-severity-index (CTSI) better correlate with need for surgery compared to the 1994-AAST, the CTSI is superior in outcome-prediction to the 2018-AAST.


Assuntos
Escala de Gravidade do Ferimento , Fígado/diagnóstico por imagem , Fígado/lesões , Baço/diagnóstico por imagem , Baço/lesões , Ferimentos não Penetrantes/diagnóstico por imagem , Ferimentos não Penetrantes/mortalidade , Traumatismos Abdominais , Adolescente , Adulto , Biometria , Sistemas de Apoio a Decisões Clínicas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Estados Unidos , Adulto Jovem
7.
J Surg Oncol ; 121(2): 382-391, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31788797

RESUMO

BACKGROUND: Short treatment-duration with early restaging is crucial to avoid liver injury after preoperative chemotherapy (preopCTX) for colorectal liver metastases (CRLM). Response evaluation according to response evaluation criteria in solid tumors (RECIST) criteria implies several limitations. Early tumor shrinkage (ETS; ≥20% size reduction <6-12 weeks) or morphological criteria (MC) may better predict oncological outcome. METHODS: In patients undergoing resection after preopCTX between 2003-2017 pathological and radiological response was reassessed according to Blazer classification, ETS, MC, and RECIST within 90 days and correlated with survival. RESULTS: Seventy-two patients were included, with a median of two (1-10) liver lesions, 53% bilobar involvement, and 7% extrahepatic disease. PreopCTX was applied for 3 months in median (1-6). During restaging after a median of 62 days, presence of ETS was associated with improved median overall survival (OS; 57.1 vs 33.7 months; P = .010) and disease-free survival (16 vs 7.2 months; P = .025). MC significantly correlated with major pathological response (P = .021). When combining ETS with optimal MC, presence of one or both factors was associated with pathological response (61.5% and 92.3%; P = .044) and OS in log-rank (P = .011), and multivariable analysis (hazard ratio [HR] 0.41; 95% confidence interval [CI], 0.19-0.90 and HR 0.32; 95%CI, 0.11-0.97). CONCLUSION: Response-grading by combined ETS/MC criteria less than 90 days after preopCTX initiation predicts pathological response and postoperative survival in CRLM.

8.
World J Emerg Surg ; 14: 29, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31236129

RESUMO

Background: A widespread shift to non-operative management (NOM) for blunt hepatic and splenic injuries has been observed in most centers worldwide. Furthermore, many countries introduced safety measures to systematically reduce severe traffic and leisure sports injuries. This study aims to evaluate the effect of these nationwide implementations on individual patient characteristics and outcomes through a time-trend analysis over 17 years in an Austrian high-volume trauma center. Methods: A retrospective review of all emergency trauma patients admitted to the Medical University of Innsbruck from 2000 to 2016. Injury severity, clinical data on admission, operative and non-operative treatment parameters, complications, and in-hospital mortality were evaluated. Results: In total, 731 patients were treated with blunt hepatic and/or splenic injuries. Among these, 368 had a liver injury, 280 splenic injury, and 83 combined hepatic/splenic injury. Initial NOM was performed in 82.6% of all patients (93.5% in hepatic and 71.8% in splenic injuries) with a success rate of 96.7%. The secondary failure rate of NOM was 3.3% and remained consistent over 17 years (p = 0.515). In terms of injury severity, we observed a reduction over time, resulting in an overall mortality rate of 4.8% and 3.5% in the NOM group (decreasing from 7.5 to 1.9% and from 5.6 to 1.3%, respectively). These outcomes confirmed an improved utilization of the NOM approach. Conclusion: Our cohort represents one of the largest Central European single-center experiences available in the literature. NOM is the standard of care for blunt hepatic and splenic injuries and successful in > 96% of all patients. This rate was quite constant over 17 years (p = 0.515). Overall, national and regional safety measures resulted in a significantly decreased severity of observed injury patterns and deaths due to blunt hepatic or splenic trauma. Although surgery is nowadays only applied in about one third of splenic injury patients in our center, these numbers might further decrease by intensified application of interventional radiology and modern coagulation management.


Assuntos
Tratamento Conservador/normas , Fígado/lesões , Baço/lesões , Ferimentos e Lesões/terapia , Adolescente , Adulto , Áustria , Estudos de Coortes , Tratamento Conservador/métodos , Tratamento Conservador/estatística & dados numéricos , Feminino , Humanos , Escala de Gravidade do Ferimento , Fígado/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Baço/fisiopatologia , Estatísticas não Paramétricas , Resultado do Tratamento , Ferimentos e Lesões/complicações , Ferimentos não Penetrantes/complicações , Ferimentos não Penetrantes/terapia
9.
Transplantation ; 103(12): 2506-2514, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30985737

RESUMO

BACKGROUND: Sarcopenia is an established risk factor predicting survival in chronically ill and trauma patients. We herein examine the assessment and clinical implication of sarcopenia in liver transplantation (LT). METHODS: Computerized tomography scans from 172 patients waitlisted for LT were analyzed by applying 6 morphometric muscle scores, including 2 density indices (psoas density [PD] and skeletal muscle density [SMD]) and 4 scores based on muscle area (total psoas area, psoas muscle index, skeletal muscle area, and skeletal muscle index). RESULTS: The prevalence of sarcopenia in our cohort ranged from 7.0% to 37.8%, depending on the score applied. Only sarcopenia as defined by the density indices PD and SMD (but not total psoas area, psoas muscle index, skeletal muscle area, or skeletal muscle index) revealed clinical relevance since it correlates significantly with postoperative complications (≥Grade III, Clavien-Dindo classification) and sepsis. Furthermore, sarcopenia predicted inferior patient and graft survival, with low muscle density (PD: <38.5 HU or SMD: <30 HU) representing an independent risk factor in a multivariate regression model (P < 0.05). Importantly, the widely used Eurotransplant donor risk index had a predictive value in nonsarcopenic patients but failed to predict graft survival in patients with sarcopenia. CONCLUSIONS: Sarcopenia revealed by low muscle density correlates with major complications following LT and acts as an independent predictor for patient and graft survival. Therefore, the application of a simple computerized tomography-morphologic index can refine an individual recipient's risk estimate in a personalized approach to transplantation.


Assuntos
Transplante de Fígado/efeitos adversos , Complicações Pós-Operatórias/diagnóstico , Músculos Psoas/diagnóstico por imagem , Sarcopenia/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Áustria/epidemiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Valor Preditivo dos Testes , Período Pré-Operatório , Prevalência , Estudos Retrospectivos , Fatores de Risco , Sarcopenia/epidemiologia , Sarcopenia/etiologia
10.
Eur Surg ; 50(6): 285-298, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30546386

RESUMO

BACKGROUND: Non-operative management (NOM) of blunt hepatic and splenic injuries has become popular in haemodynamically stable adult patients, despite uncertainty about efficacy, patient selection, and details of management. Up-to-date strategies and practical recommendations are presented. METHODS: A selective literature search was conducted in PubMed and the Cochrane Library (1989-2016). RESULTS: No randomized clinical trial was found. Non-randomized controlled trials and large retrospective and prospective series dominate. Few systematic reviews and meta-analyses are available. NOM of selected patients with blunt liver and spleen injuries is associated with low morbidity and mortality. Only data of limited evidence are available on intensity and duration of patient monitoring, repeat imaging, antithrombotic prophylaxis and return to normal activity. There is high-level evidence on early mobilisation and post-splenectomy vaccination. CONCLUSION: NOM of blunt liver or spleen injuries is a worldwide trend, but the literature does not provide high-grade evidence for this strategy.

11.
Front Pharmacol ; 9: 217, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29670522

RESUMO

Background: A left ventricular (LV) thrombus is detected in approximately 5-10% of patients after myocardial infarction (MI). If left untreated, these LV thrombi carry a significant risk of complications including embolic stroke. According to current guidelines, anticoagulation with vitamin K antagonists (VKA) is recommended to treat a LV thrombus. Case presentation: An 87 year old patient was referred to our department with non ST-elevation MI. Five months before, he had been diagnosed with a subacute ST elevation MI, which had been treated conservatively. Recently, a rectal neoplasia had been diagnosed, but not operated yet. The patient underwent coronary angiography with implantation of two drug eluting stents (Cre8) requiring dual antiplatelet therapy. During ventriculography an apical LV thrombus of 16 mm diameter was detected. Due to the high bleeding risk in this patient, VKA therapy with potentially fluctuating international normalized ratio (INR) values was considered unsuitable. Therefore, dabigatran at a dose of 110 mg bid was chosen as anticoagulation therapy. After 4 weeks, cardiac computed tomography was performed, which failed to detect the LV thrombus described previously. Notably, triple therapy with dabigatran, clopidogrel, and aspirin was well tolerated without evidence for bleeding. The surgical resection of the rectal neoplasm was performed 2 months later without bleeding complications. Discussion: Anticoagulation is effective in patients with MI and a LV thrombus in reducing the risk of embolization and in dissolving the thrombus. Our case is complex due to the required triple therapy, very old age and significant bleeding risk of our patient due to the rectal neoplasia. Although only few reports are available for the use of non VKA oral anticoagulants (NOAC) in this indication, we chose dabigatran at a dose of 110 mg bid added to dual antiplatelet therapy for our patient. Besides the advantage of a predictable pharmacokinetic profile of NOAC in contrast to VKA, the effect of dabigatran can rapidly be reversed by idaruzicumab in the case of severe bleeding. Conclusion remarks: Physicians should carefully weigh the risk of thromboembolic events versus the risk of bleeding when combining antiplatelet with anticoagulation therapy.

12.
J Wrist Surg ; 6(1): 74-79, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28119800

RESUMO

Background Complete dislocation of the distal radioulnar joint (DRUJ) is a rare injury. Dislocation can present as uni- or multidirectional, acute or chronic, reducible or irreducible. It can occur due to isolated loss of ligamentous restraints or more frequent in Galeazzi - or Essex-Lopresti-type fractures. Case Description A 28-year-old man sustained a distal radius fracture and presented after conservative treatment with blocked supination. Examination revealed a malunion of the distal radius in combination with an irreducible dorsal dislocation of the DRUJ. Corrective osteotomy of the distal radius was performed, the DRUJ was reduced, and the ulnar avulsed triangular fibrocartilage complex (TFCC) refixed with transosseous sutures. Redislocation occurred 8 weeks later. Revision surgery showed a palmar dislocated TFC fixed in a palmar scar formation along the distal interosseous membrane (DIOM). The scar was released and a rotation osteotomy of the distal ulna was performed. At follow-up, the patient was pain-free, had good range of motion, and returned to work and sport activities. Literature Review For reconstruction of chronic complete dislocations of the DRUJ, ligament plasty procedures are described. In case of additional cartilage damage, salvage procedures are recommended. Clinical Relevance We report a procedure in which the rotation of the distal ulna is corrected to restore DRUJ congruity in chronic dislocations. The rotation osteotomy described is useful in gross ligamentous instability following loss of constraint by the TFCC and the DIOM.

13.
Dentomaxillofac Radiol ; 46(4): 20160452, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28059562

RESUMO

OBJECTIVES: The objective of this study was to determine how iterative reconstruction technology (IRT) influences contrast and spatial resolution in ultralow-dose dentomaxillofacial CT imaging. METHODS: A polymethyl methacrylate phantom with various inserts was scanned using a reference protocol (RP) at CT dose index volume 36.56 mGy, a sinus protocol at 18.28 mGy and ultralow-dose protocols (LD) at 4.17 mGy, 2.36 mGy, 0.99 mGy and 0.53 mGy. All data sets were reconstructed using filtered back projection (FBP) and the following IRTs: adaptive statistical iterative reconstructions (ASIRs) (ASIR-50, ASIR-100) and model-based iterative reconstruction (MBIR). Inserts containing line-pair patterns and contrast detail patterns for three different materials were scored by three observers. Observer agreement was analyzed using Cohen's kappa and difference in performance between the protocols and reconstruction was analyzed with Dunn's test at α = 0.05. RESULTS: Interobserver agreement was acceptable with a mean kappa value of 0.59. Compared with the RP using FBP, similar scores were achieved at 2.36 mGy using MBIR. MIBR reconstructions showed the highest noise suppression as well as good contrast even at the lowest doses. Overall, ASIR reconstructions did not outperform FBP. CONCLUSIONS: LD and MBIR at a dose reduction of >90% may show no significant differences in spatial and contrast resolution compared with an RP and FBP. Ultralow-dose CT and IRT should be further explored in clinical studies.


Assuntos
Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radiografia Dentária/métodos , Tomografia Computadorizada por Raios X/métodos , Imagens de Fantasmas , Doses de Radiação
14.
Br J Radiol ; 89(1060): 20151055, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26859336

RESUMO

OBJECTIVE: The aim of this study was to evaluate whether application of ultralow dose protocols and iterative reconstruction technology (IRT) influence quantitative Hounsfield units (HUs) and contrast-to-noise ratio (CNR) in dentomaxillofacial CT imaging. METHODS: A phantom with inserts of five types of materials was scanned using protocols for (a) a clinical reference for navigated surgery (CT dose index volume 36.58 mGy), (b) low-dose sinus imaging (18.28 mGy) and (c) four ultralow dose imaging (4.14, 2.63, 0.99 and 0.53 mGy). All images were reconstructed using: (i) filtered back projection (FBP); (ii) IRT: adaptive statistical iterative reconstruction-50 (ASIR-50), ASIR-100 and model-based iterative reconstruction (MBIR); and (iii) standard (std) and bone kernel. Mean HU, CNR and average HU error after recalibration were determined. Each combination of protocols was compared using Friedman analysis of variance, followed by Dunn's multiple comparison test. RESULTS: Pearson's sample correlation coefficients were all >0.99. Ultralow dose protocols using FBP showed errors of up to 273 HU. Std kernels had less HU variability than bone kernels. MBIR reduced the error value for the lowest dose protocol to 138 HU and retained the highest relative CNR. ASIR could not demonstrate significant advantages over FBP. CONCLUSIONS: Considering a potential dose reduction as low as 1.5% of a std protocol, ultralow dose protocols and IRT should be further tested for clinical dentomaxillofacial CT imaging. ADVANCES IN KNOWLEDGE: HU as a surrogate for bone density may vary significantly in CT ultralow dose imaging. However, use of std kernels and MBIR technology reduce HU error values and may retain the highest CNR.


Assuntos
Tomografia Computadorizada Multidetectores/métodos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Tomografia Computadorizada Multidetectores/instrumentação , Imagens de Fantasmas , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/instrumentação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Razão Sinal-Ruído
15.
AJR Am J Roentgenol ; 204(3): 563-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25714286

RESUMO

OBJECTIVE. The purpose of this article is to evaluate 2D and 3D image quality of high-resolution ultralow-dose CT images of the craniofacial bone for navigated surgery using adaptive statistical iterative reconstruction (ASIR) and model-based iterative reconstruction (MBIR) in comparison with standard filtered backprojection (FBP). MATERIALS AND METHODS. A formalin-fixed human cadaver head was scanned using a clinical reference protocol at a CT dose index volume of 30.48 mGy and a series of five ultralow-dose protocols at 3.48, 2.19, 0.82, 0.44, and 0.22 mGy using FBP and ASIR at 50% (ASIR-50), ASIR at 100% (ASIR-100), and MBIR. Blinded 2D axial and 3D volume-rendered images were compared with each other by three readers using top-down scoring. Scores were analyzed per protocol or dose and reconstruction. All images were compared with the FBP reference at 30.48 mGy. A nonparametric Mann-Whitney U test was used. Statistical significance was set at p < 0.05. RESULTS. For 2D images, the FBP reference at 30.48 mGy did not statistically significantly differ from ASIR-100 at 3.48 mGy, ASIR-100 at 2.19 mGy, and MBIR at 0.82 mGy. MBIR at 2.19 and 3.48 mGy scored statistically significantly better than the FBP reference (p = 0.032 and 0.001, respectively). For 3D images, the FBP reference at 30.48 mGy did not statistically significantly differ from all reconstructions at 3.48 mGy; FBP and ASIR-100 at 2.19 mGy; FBP, ASIR-100, and MBIR at 0.82 mGy; MBIR at 0.44 mGy; and MBIR at 0.22 mGy. CONCLUSION. MBIR (2D and 3D) and ASIR-100 (2D) may significantly improve subjective image quality of ultralow-dose images and may allow more than 90% dose reductions.


Assuntos
Ossos Faciais/diagnóstico por imagem , Ossos Faciais/cirurgia , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Doses de Radiação , Crânio/diagnóstico por imagem , Crânio/cirurgia , Tomografia Computadorizada por Raios X/métodos , Cadáver , Humanos , Modelos Teóricos
19.
J Cardiovasc Comput Tomogr ; 5(5): 317-24, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21875827

RESUMO

BACKGROUND: Cardiac CT provides volumetric data that enables characterization of the myocardium. OBJECTIVE: We evaluated intraobserver, interobserver, and interstudy reproducibility of left ventricular (LV) and right ventricular (RV) mass quantification with cardiac CT. METHODS: Thirty-eight patients who underwent cardiac CT twice within 365 days were included in this analysis. Functional reconstructions in 10% steps throughout the R-R interval and axial 1.5-mm sections were used. Semiautomatic contour detection was used to trace epicardial and endocardial borders in all cardiac phases for calculation of LV and RV ejection fraction, end-diastolic volume, end-systolic volume, cardiac output, stroke volume, and ventricular mass. For each study 2 observers measured LV and RV mass twice. RESULTS: LV mass parameters derived from semiautomatic contour detection algorithm had excellent intraobserver (r = 1.00), interobserver (r = 0.99), and interstudy (r = 0.99) reproducibility (P < 0.0001). Average end-diastolic LV mass was 146.2 ± 42.9 g at the first CT study and 146.8 ± 44.4 g at the second study. For measuring RV mass, reproducibility was good on all levels (r = 0.78, r = 0.78, and r = 0.68, respectively, with an average end-diastolic mass of 25.7 ± 5.8 g at the first study and 24.4 ± 4.8 g at the second study. CONCLUSION: Quantification of LV mass at cardiac CT with the threshold-based, region-growing semiautomatic segmentation analysis software evaluated here is highly observer independent and reproducible. This largely holds true for the estimation of RV mass as well; however, further improvements are needed to optimize reproducibility for RV mass quantification.


Assuntos
Ventrículos do Coração/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Direita/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Débito Cardíaco , Feminino , Ventrículos do Coração/fisiopatologia , Humanos , Hipertrofia Ventricular Esquerda/fisiopatologia , Hipertrofia Ventricular Direita/fisiopatologia , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Tamanho do Órgão , Valor Preditivo dos Testes , Interpretação de Imagem Radiográfica Assistida por Computador , Reprodutibilidade dos Testes , Estudos Retrospectivos , Software , Volume Sistólico , Função Ventricular Esquerda , Função Ventricular Direita
20.
J Card Surg ; 26(2): 162-4, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21198843

RESUMO

A 64-year-old male underwent surgical resection of a large liposarcoma of the mediastinum. The management of this unusual tumor is the subject of this case report.


Assuntos
Lipossarcoma/diagnóstico , Neoplasias do Mediastino/diagnóstico , Procedimentos Cirúrgicos Torácicos/métodos , Diagnóstico Diferencial , Humanos , Lipossarcoma/cirurgia , Masculino , Neoplasias do Mediastino/cirurgia , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
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