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1.
Can Assoc Radiol J ; 75(3): 534-541, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38189316

RESUMO

BACKGROUND: Multi-detector contrast-enhanced abdominal computed tomography (CT) allows for the accurate detection and classification of traumatic splenic injuries, leading to improved patient management. Their effective use requires rapid study interpretation, which can be a challenge on busy emergency radiology services. A machine learning system has the potential to automate the process, potentially leading to a faster clinical response. This study aimed to create such a system. METHOD: Using the American Association for the Surgery of Trauma (AAST), spleen injuries were classified into 3 classes: normal, low-grade (AAST grade I-III) injuries, and high-grade (AAST grade IV and V) injuries. Employing a 2-stage machine learning strategy, spleens were initially segmented from input CT images and subsequently underwent classification via a 3D dense convolutional neural network (DenseNet). RESULTS: This single-centre retrospective study involved trauma protocol CT scans performed between January 1, 2005, and July 31, 2021, totaling 608 scans with splenic injuries and 608 without. Five board-certified fellowship-trained abdominal radiologists utilizing the AAST injury scoring scale established ground truth labels. The model achieved AUC values of 0.84, 0.69, and 0.90 for normal, low-grade injuries, and high-grade splenic injuries, respectively. CONCLUSIONS: Our findings demonstrate the feasibility of automating spleen injury detection using our method with potential applications in improving patient care through radiologist worklist prioritization and injury stratification. Future endeavours should concentrate on further enhancing and optimizing our approach and testing its use in a real-world clinical environment.


Assuntos
Aprendizado de Máquina , Baço , Tomografia Computadorizada por Raios X , Humanos , Baço/lesões , Baço/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Masculino , Adulto , Feminino , Pessoa de Meia-Idade , Traumatismos Abdominais/diagnóstico por imagem , Idoso
2.
Eur Arch Otorhinolaryngol ; 272(4): 873-876, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24986427

RESUMO

Differentiation of a recent nasal bone fracture from an old one may become of utmost importance, especially in medico-legal issues. The aim of this study was to demonstrate the value of high-resolution ultrasonography (HRUS) in determining the time of nasal bone fracture. A longitudinal, descriptive-analytic study was done on 45 patients with a clinical manifestation of acute unilateral nasal bone fracture. After a thorough rhinologic physical examination, HRUS was performed by an expert consultant who was blinded to the clinical data of the patients. All patients were followed-up for 6 months: in the first 5 days, 3rd, 6th, 12th and 24th weeks after the trauma. In each session, the ultrasonographic findings were recorded. Thirty-six cases (mean age, 27 years) completed the study course successfully. On HRUS, subperiosteal hematoma, with a mean thickness of 1.14 mm (0.79-1.31 mm) was highly sensitive (100 %) for the diagnosis of nasal bone fracture during the first few days after the trauma, but it was present in 13 cases in the 6th week, with a mean thickness of 0.71 mm (0.62-0.80 mm), and disappeared in all patients in the 24th week, with a mean thickness of 0.47 mm (almost equal to the non-traumatic side). According to the changes of subperiosteal reaction on the traumatic side and by means of generalized linear model and generalized estimating equations, we proposed an equation to estimate the time of nasal bone trauma. In conclusion, HRUS is a reliable diagnostic tool for estimating the time of nasal bone fracture.


Assuntos
Traumatismos Faciais/complicações , Osso Nasal , Fraturas Cranianas , Adulto , Traumatismos Faciais/diagnóstico , Traumatismos Faciais/fisiopatologia , Feminino , Seguimentos , Humanos , Masculino , Osso Nasal/diagnóstico por imagem , Osso Nasal/lesões , Gravidade do Paciente , Exame Físico/métodos , Reprodutibilidade dos Testes , Fraturas Cranianas/diagnóstico por imagem , Fraturas Cranianas/etiologia , Fraturas Cranianas/fisiopatologia , Fatores de Tempo , Ultrassonografia
3.
Pol J Radiol ; 79: 323-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25250100

RESUMO

BACKGROUND: The purpose of this study was to compare patients with multiple sclerosis and healthy control subjects as regards hemodynamics of cerebral venous drainage. MATERIAL/METHODS: Between December 2012 and May 2013, 44 consecutive patients with multiple sclerosis and 44 age- and sex-matched healthy subjects underwent the B-mode, color Doppler, and duplex Doppler evaluations of the internal jugular vein (IJV) and vertebral vein. The following four parameters were investigated: IJV stenosis, reversal of postural control of the cerebral venous outflow pathways, absence of detectable blood flow in the IJVs and/or vertebral veins, and reflux in the IJVs and/or vertebral veins in the sitting or supine position. RESULTS: In the study group, IJV stenosis, postural control reversal of the cerebral venous outflow pathways, and absence of flow in the IJVs and/or vertebral veins were found in 3 (6.8%), 2 (4.5%), and 3 (6.8%) patients, respectively. In the control group, IJV stenosis (P=0.12), postural control reversal of the cerebral venous outflow pathways (P=0.50), and absence of flow (P=0.12) were not detected. Abnormal reflux was found neither in multiple sclerosis patients nor in healthy subjects. CONCLUSIONS: No significant difference in the cerebral venous drainage through the IJV or vertebral vein was found between patients with multiple sclerosis and healthy subjects within any of the investigated ultrasonographic parameters.

4.
Cancer Imaging ; 22(1): 55, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36195953

RESUMO

OBJECTIVES: To compare the diagnostic performance of international hepatocellular carcinoma (HCC) guidelines with gadoxetic acid-enhanced MRI (EOB-MRI) and contrast-enhanced Computed tomography (CECT) and their impact on liver transplant (LT) allocation in cirrhotic patients with explant histopathology correlation. METHODS: In this prospective single-centre ethics-approved study, 101 cirrhotic patients were consecutively enrolled with informed consent from the pre-LT clinic. They underwent CECT and EOB-MRI alternately at three monthly intervals until LT or removal from LT list. Two abdominal radiologists, blinded to explant histopathology, independently recorded liver lesions visible on CECT and EOB-MRI. Imaging-based HCC scores were assigned to non-treated liver lesions utilizing Liver Imaging Reporting and Data System (LI-RADS), European Association for the Study of the Liver (EASL), Asian-Pacific Association for the Study of the Liver (APASL) and Korean Liver Cancer Association-National Cancer Center (KLCA) guidelines. Liver explant histopathology was the reference standard. Simulated LT eligibility was assessed as per Milan criteria (MC) in reference to explant histopathology. RESULTS: One hundred and three non-treated HCC and 12 non-HCC malignancy were identified at explant histopathology in 34 patients (29 men, 5 women, age 55-73 years). Higher HCC sensitivities of statistical significance were observed with EOB-MRI for LI-RADS 4 + 5, APASL and KLCA compared to LI-RADS 5 and EASL with greatest sensitivity obtained for LIRADS 4 + 5 lesions. HCC sensitivities by all guidelines with both EOB-MRI and CECT were significantly lower if all histopathology-detected HCCs were included in the analysis, compared to imaging-visible lesions only. A significantly greater variation in HCC sensitivity was noted across the guidelines with EOB-MRI compared to CECT. No significant differences in simulated LT eligibility based on MC were observed across the HCC scoring guidelines with EOB-MRI or CECT. CONCLUSION: HCC sensitivities are variable depending on scoring guideline, lesion size and imaging modality utilised. Prior studies that included only lesions visible on pre-operative imaging overestimate the diagnostic performance of HCC scoring guidelines. Per-lesion differences in HCC diagnosis across these guidelines did not impact patient-level LT eligibility based on MC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , Idoso , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/cirurgia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodos
5.
Turk J Urol ; 45(1): 73-75, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30668310

RESUMO

Varicocele represents the main cause of male infertility. Right-sided varicocele is rare and can be due to renal malignancy or a venous abnormality. The most common anomaly of the inferior vena cava (IVC) is interruption of IVC with azygos continuation, which is recognized as an uncommon congenital anomaly. The prevalence of the interruption of IVC is less than 0.3% in the healthy population. We describe the case of a 26-year-old man who had right varicocele because of a right-sided IVC with a retro-aortic left renal vein and azygos continuation. The right and left IVCs received the right and left common iliac veins, respectively, and the left renal vein crossed posteriorly to the aorta and joined the right IVC. The right IVC continued cephalad as the azygos vein within the retrocrural space. Isolated right-sided varicoceles are uncommon, but practitioners should be aware of such a condition. In case of a venous anomaly, clinicians should aware of the association with other important clinical presentations.

6.
Exp Clin Transplant ; 6(2): 161-7, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18816245

RESUMO

OBJECTIVES: To present new approaches to using duplex Doppler scanning to detect kidney complications in the early posttransplant period. MATERIALS AND METHODS: We assessed the resistive index and the pulsatility index in 127 renal transplant patients (73 men, mean age, 35.2 +/- 14 years) who underwent duplex Doppler scanning on the first, third, and fifth days after transplant. Biopsies were performed in patients suspected of having graft dysfunction owing to clinical and laboratory findings. To differentiate complicated from healthy grafts, a receiver operating characteristic curve analysis was done, and an area under the curve was calculated for each variable. RESULTS: In total, 47 grafts (37%) became complicated (40 rejections). The mean resistive index and mean pulsatility indexwere statistically significantly higher on the first, third, and fifth days after transplant in patients with complicated grafts than they were in patients with noncomplicated grafts (P < .0001). The mean resistive index and mean pulsatility index showed a significant rise from the first to the fifth day in patients with complicated grafts (P = .014). The area under the curve of the receiver operating characteristic curve for resistive index and pulsatility index on successive days was statistically significant (P < .0001). The resistive index and the pulsatility index area under the curve were statistically significantly lower on the first day than they were on subsequent days. Considering the maximum value of a serially measured resistive index and pulsatility index (which were determined by comparing 3 measurements on the fifth day and selecting the highest one) as a new variable showed a better area under the curve compared with that calculated on the third day (P = .05 for resistive index; P = .012 for pulsatility index). CONCLUSIONS: The resistive index and the pulsatility index are effective means of diagnosing posttransplant renal complications. Including a serial assessment and considering the maximum values could improve the diagnostic efficacy on the fifth day after transplant.


Assuntos
Rejeição de Enxerto/diagnóstico por imagem , Rejeição de Enxerto/fisiopatologia , Nefropatias/diagnóstico por imagem , Nefropatias/fisiopatologia , Transplante de Rim/diagnóstico por imagem , Transplante de Rim/fisiologia , Complicações Pós-Operatórias , Adolescente , Adulto , Idoso , Área Sob a Curva , Biópsia , Criança , Pré-Escolar , Testes Diagnósticos de Rotina , Feminino , Rejeição de Enxerto/patologia , Humanos , Rim/diagnóstico por imagem , Rim/patologia , Rim/fisiologia , Nefropatias/patologia , Transplante de Rim/patologia , Masculino , Pessoa de Meia-Idade , Curva ROC , Ultrassonografia Doppler Dupla
7.
Turk Neurosurg ; 24(6): 978-81, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25448220

RESUMO

Pilocytic astrocytoma with leptomeningeal dissemination is a rare phenomenon and can be associated with obstructive hydrocephalus and an unfavorable prognosis. Herein, we report a seventeen-year-old boy with a history of ventriculo-peritoneal shunt insertion due to severe hydrocephalus who presented with progressive headache and vomiting together with ocular and cerebellar signs and symptoms. Neuroimaging confirmed the presence of multiple intracranial masses in the cerebellum and thalamus. Intracranial dissemination of tumor to the the leptomeninges was seen during neuroendoscopy. Simultaneous biopsy and endoscopic third ventriculostomy were performed and the diagnosis of low-grade pilocytic astrocytoma with leptomeningeal dissemination was made by histological examination. The patient underwent chemotherapy in combination with radiotherapy to reduce the risk of reoccurrence of the primary tumor and was followed for one year.


Assuntos
Astrocitoma/patologia , Neoplasias Encefálicas/patologia , Neoplasias Meníngeas/secundário , Adolescente , Astrocitoma/tratamento farmacológico , Astrocitoma/radioterapia , Astrocitoma/cirurgia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirurgia , Humanos , Hidrocefalia , Masculino , Neoplasias Meníngeas/tratamento farmacológico , Neoplasias Meníngeas/radioterapia , Neoplasias Meníngeas/cirurgia , Neuroendoscopia , Derivação Ventriculoperitoneal , Ventriculostomia
8.
Urolithiasis ; 41(2): 159-63, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23503878

RESUMO

This study was designed to evaluate ureterovesical jet dynamics in obstructed ureter and to compare it with those of contralateral unobstructed side. Forty-six patients with diagnosis of ureteral stone, based on imaging findings in computed tomography were enrolled in this study. The gray-scale ultrasound exam from both kidneys and urinary bladder was performed. Then, ureterovesical jet characteristics including ureteral jet frequency, duration and peak velocity were assessed by color Doppler and duplex Doppler studies in both obstructed and unobstructed ureters by a radiologist, 15-30 min after oral hydration with 750-1,000 mL of water. When compared with contralateral normal side, the ureterovesical jet in obstructed ureter showed less frequency (0.59 vs. 3.04 jets/min; P < 0.05), shorter duration (1.24 vs. 5.26 s; P < 0.05) and lower peak velocity (5.41 vs. 32.09 cm/s; P < 0.05). The cut-off points of 1.5 jets/min, 2.5 s and 19.5 cm/s for difference of ureteral jet frequency, duration and peak velocity between obstructed and contralateral normal ureters yielded sensitivities of 97.8, 95.6 and 100 % and specificities of 87, 87.9 and 97.8 %, respectively for diagnosis of ureteral obstruction. Given the safety of Doppler study and significant differences in flow dynamics of obstructed versus unobstructed ureters, our findings demonstrated the utility of Doppler ultrasound examination as a useful adjunct to gray-scale ultrasound by improving the accuracy of ultrasound exam in diagnosis of ureteral obstruction.


Assuntos
Cálculos Ureterais/diagnóstico por imagem , Obstrução Ureteral/diagnóstico por imagem , Adulto , Idoso , Feminino , Humanos , Hidrodinâmica , Hidronefrose/diagnóstico por imagem , Hidronefrose/etiologia , Hidronefrose/urina , Rim/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Ultrassonografia Doppler em Cores , Ultrassonografia Doppler Dupla , Cálculos Ureterais/complicações , Cálculos Ureterais/urina , Obstrução Ureteral/etiologia , Obstrução Ureteral/urina , Bexiga Urinária/diagnóstico por imagem , Adulto Jovem
9.
Acta Orthop Traumatol Turc ; 46(5): 346-52, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23268819

RESUMO

OBJECTIVE: The aim of this study was to determine the efficacy of sonographically guided intra-flexoral sheath corticosteroid injection in the treatment of trigger thumb. METHODS: This study included 112 trigger thumbs of 104 patients (7 males, 97 females; mean age: 52.11 years) studied prospectively from 2009 to 2011. All patients experienced pain, tenderness, discomfort and/or triggering with flexion/extension of the thumb and palpable nodules at the level of the A1 pulley. Ultrasonographically guided corticosteroid injection was performed on all affected thumbs. Thumb improvement was evaluated using the Quinnell grading system and patients were followed up for one year. RESULTS: All 112 thumbs received one ultrasonographically guided corticosteroid injection. Fifteen thumbs (13.4%) needed re-injection and/or surgery during their one year follow-up. Eight (53.3%) of these 15 cases, had a pre-treatment Quinnell Grade of 4, six (40%) thumbs were Grade 3 and one (6.7%) was Grade 2. Twelve were re-injected, two underwent surgery without re-injection and one underwent surgery after showing no improvement following re-injection. There was a significant reduction in the post-injection Quinnell grade (p<0.0001). One year after the initial injection, 108 thumbs (96.4%) were completely symptom-free. CONCLUSION: Sonographically guided intra-flexoral sheath corticosteroid injection is an effective method in the treatment of trigger thumb and reduces the need for surgery.


Assuntos
Corticosteroides/administração & dosagem , Dedo em Gatilho/diagnóstico por imagem , Dedo em Gatilho/tratamento farmacológico , Ultrassonografia Doppler , Adulto , Idoso , Estudos de Coortes , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Humanos , Injeções Intralesionais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recuperação de Função Fisiológica , Fatores de Tempo , Resultado do Tratamento
10.
ACS Appl Mater Interfaces ; 3(11): 4518-24, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21999213

RESUMO

A combination of bioceramics and polymeric nanofibers holds promising potential for bone tissue engineering applications. In the present study, hydroxyapatite (HA), bioactive glass (BG), and tricalcium phosphate (TCP) particles were coated on the surface of electrospun poly(L-lactic acid) (PLLA) nanofibers, and the capacity of the PLLA, BG-PLLA, HA-PLLA, HA-BG-PLLA, and TCP-PLLA scaffolds for bone regeneration was investigated in rat critical-size defects using digital mammography, multislice spiral-computed tomography (MSCT) imaging, and histological analysis. Electrospun scaffolds exhibited a nanofibrous structure with a homogeneous distribution of bioceramics along the surface of PLLA nanofibers. A total of 8 weeks after implantation, no sign of complication or inflammation was observed at the site of the calvarial bone defect. On the basis of imaging analysis, a higher level of bone reconstruction was observed in the animals receiving HA-, BG-, and TCP-coated scaffolds compared to an untreated control group. In addition, simultaneous coating of HA and BG induced the highest regeneration among all groups. Histological staining confirmed these findings and also showed an efficient osseointegration in HA-BG-coated nanofibers. On the whole, it was demonstrated that nanofibrous structures could serve as an appropriate support to guide the healing process, and coating their surface with bioceramics enhanced bone reconstruction. These bioceramic-coated scaffolds can be used as new bone-graft substitutes capable of efficiently inducing osteoconduction and osseointegration in orthopedic fractures and defects.


Assuntos
Desenvolvimento Ósseo , Durapatita/química , Ácido Láctico/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis/química , Regeneração Óssea , Vidro/química , Masculino , Ratos , Ratos Sprague-Dawley , Engenharia Tecidual/instrumentação
11.
Int Arch Allergy Immunol ; 134(3): 253-9, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15178896

RESUMO

BACKGROUND: Chronic granulomatous disease (CGD) represents a group of inherited disorders of the phagocytic system, involving recurrent infections at different sites, especially the respiratory system. The present study was accomplished in order to determine the clinical spectrum of Iranian patients with CGD. METHODS: Forty-one patients (29 males and 12 females) with CGD, who had already been referred to two immunodeficiency referral centers in Iran, were reviewed during a 22-year period (1980-2002). RESULTS: These patients belonged to 34 families, and 56% of them were consanguineous. The median age at the time of study was 12 years (3 months to 22 years). The median age at onset of symptoms was 4 months (1 month to 12 years), and the median diagnostic age was 5.5 years (2 months to 20 years), with a diagnostic delay of 3 years on average. The most common presenting complaint in our CGD patients was lymphadenopathy (seen in 11 patients, 26.8%). The most common manifestations of CGD (in descending order) were lymphadenopathy (75.6%), pulmonary infections (65.9%) and skin involvement (63.4%) during their illness, followed by gastrointestinal (56.1%), skeletal (29.3%), upper respiratory tract (26.8%) and central nervous system (2.4%) involvement. CONCLUSIONS: Early diagnosis of the disease is crucial. In view of the possibility of timely treatment, i.e. prophylactic treatment of infection, CGD should be excluded in any patient with unexplained infections or granulomas.


Assuntos
Doença Granulomatosa Crônica , Adolescente , Adulto , Idade de Início , Criança , Pré-Escolar , Feminino , Doença Granulomatosa Crônica/diagnóstico , Doença Granulomatosa Crônica/fisiopatologia , Humanos , Lactente , Irã (Geográfico) , Doenças Linfáticas/etiologia , Masculino , Prognóstico , Sistema de Registros
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