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1.
Indian J Surg Oncol ; 15(2): 385-396, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38741646

RESUMO

A prospective cross-sectional study was conducted to correlate clinically, radiologically, and pathologically the mandibular invasion in carcinoma bucco-alveolar complex. All biopsy-proven oral cavity cancer cases (64 patients) were assessed clinically and radiologically for involvement of the mandible. Preoperative clinicoradiological findings were compared with postoperative histopathological findings. In our study, oral cancer was 4 times more prevalent in males as compared to females and clinical evaluation was found to be highly sensitive in predicting mandibular invasion. Orthopantomogram showed sensitivity of 66.6% and specificity of 100%. CT scan showed sensitivity of 100% and specificity of 46% whereas MRI showed sensitivity of 54.5% and a specificity of 96%. MRI correlates well with final histopathology in predicting size of tumor. Prevalence of bony invasion in carcinoma oral cavity was 18%. We noted an inverse relation with tumor differentiation and mandibular invasion, and none of the verrucous carcinoma lesions showed mandibular invasion. Association of clinical T and N staging with postoperative histopathology was found to be statistically significant. Despite recent advances in molecular biology, radiological techniques, and newer modalities like visual surgical planning, exact measurement of bone invasion is still challenging. At present, CT scan and MRI along with clinical evaluation are widely used to evaluate mandibular invasion in carcinoma oral cavity, and all these are complementary to each other. The recent progress in tissue engineering technologies and stem cell biology has significantly promoted the development of regenerative reconstruction of jawbone defects.

2.
SA J Radiol ; 28(1): 2778, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628267

RESUMO

This report presents an extremely rare case of papillary meningioma with prominent flow voids and increased perfusion parameters on MRI in a 28-year-old male presenting with headache. This knowledge helped the neurosurgeon to minimise intra-operative blood loss and achieve a favourable post-surgical outcome. Contribution: A rare case of papillary meningioma and its differentiating features from typical meningiomas have been discussed considering its implications for management as well as prognostication to reduce morbidity and mortality.

3.
SA J Radiol ; 26(1): 2480, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36337074

RESUMO

Background: Meningiomas are the most prevalent of all intracranial tumours. Although they are mostly benign, about 20% of meningiomas are atypical or malignant. Knowledge of their histologic grade can be clinically useful while planning surgery. Objectives: To differentiate between various grades and subtypes of meningiomas with advanced MR parameters. Method: We assessed the advanced MR imaging characteristics of 27 histopathologically confirmed meningiomas on a 3T MRI, of which 23 were grade I meningiomas (2 fibroblastic, 9 meningothelial, 9 transitional, 3 unspecified) and 4 were grade II/III meningiomas (2 atypical, 1 papillary, 1 anaplastic). Analysis of the ADC, FA, λ1, λ2, λ3 and mean diffusivity was performed using standard post-processing software. Results: The mean size of atypical meningiomas (5.9 cm ± 0.7 cm) was significantly higher (p = 0.038, 95% confidence interval [CI]) than that of typical meningiomas (4.6 cm ± 1.6 cm) with a cut-off value of 6.05 cm (75% sensitivity and 87% specificity). The mean cerebral blood flow (CBF) (ASL) of atypical meningiomas (286.70 ± 8.06) was significantly higher (p = 0.0000141, 95% CI) than that of typical meningiomas (161.09 ± 87.04) with a cut-off value of 276.75 (66.7% sensitivity and 75% specificity). Among the typical meningiomas, transitional subtypes had the lowest ADC. High FA and planar coefficient (CP) values and low λ3 and spherical coefficient (CS) values were seen in fibroblastic meningiomas. Fibroblastic meningiomas also showed the lowest vascularity among typical meningiomas. Conclusion: Tumour size and ASL perfusion are two parameters that could differentiate between typical and atypical meningiomas while ADC, FA, λ3, CP, CS, rCBF and rCBV may be helpful in distinguishing different subtypes of typical meningiomas.

4.
Indian J Radiol Imaging ; 31(4): 1019-1022, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35136520

RESUMO

Systemic sclerosis is a connective tissue disorder of unknown etiology. Although it is a multisystemic disorder, skin thickening is considered as a hallmark of the disease. It usually involves the lungs, gastrointestinal, and musculoskeletal systems. However, a rare subset of systemic sclerosis, systemic sclerosis sine scleroderma, is characterized by internal organ involvement and positive serologic markers with the total or partial absence of cutaneous manifestations. We present a rare association of osteopetrosis in a case of systemic sclerosis sine scleroderma, in a 22-year-old male patient, who presented with pulmonary symptoms as his chief complaints, unreported so far in literature.

5.
Braz. arch. biol. technol ; 62: e19180486, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1055380

RESUMO

Abstract Breast cancer is the most commonly witnessed cancer amongst women around the world. Computer aided diagnosis (CAD) have been playing a significant role in early detection of breast tumors hence to curb the overall mortality rate. This work presents an enhanced empirical study of impact of dominance-based filtering approach on performances of various state-of-the-art classifiers. The feature dominance level is proportional to the difference in means of benign and malignant tumors. The experiments were done on original Wisconsin Breast Cancer Dataset (WBCD) with total nine features. It is found that the classifiers' performances for top 4 and top 5 dominant-based features are almost equivalent to performances for all nine features. Artificial neural network (ANN) is come forth as the best performing classifier among all with accuracies of 98.9% and 99.6% for top 4 and top 5 dominant features respectively. The error rate of ANN between all nine and top 4 &5 dominant features is less than 2% for four performance evaluation parameters namely sensitivity, specificity, accuracy and AUC. Thus, it can be stated that the dominance-based filtering approach is appropriate for selecting a sound set of features from the feature pool, consequently, helps to reduce computation time with no deterioration in classifier's performance.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Diagnóstico por Computador/instrumentação , Aprendizado de Máquina , Redes Neurais de Computação
6.
Photomed Laser Surg ; 27(4): 547-52, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19694506

RESUMO

OBJECTIVE: Our aim was to histologically evaluate the thermal changes in bovine intervertebral discs caused by 980-nm diode and 1064-nm Nd:YAG lasers. Further aims were to standardize the technique for in vivo animal research and to study its efficacy for clinical practice. BACKGROUND: When conservative methods fail, surgery has so far been the only measure for severe back pain due to disc prolapse and herniation. Recently, the minimally invasive technique of laser disc decompression has become more popular because it has advantages over open surgery in properly selected cases. METHODS: In vitro studies were done with Nd:YAG and diode lasers (1064 and 980 nm, respectively) on bovine intervertebral discs using a bare fiber tip or a focusing lens attached to a fiber tip. These studies were followed by in vivo studies in a canine model using a Nd:YAG laser with a bare fiber tip. Autopsies were done immediately and at 3, 6, 9, and 12 mo after ablation and the histopathology of excised discs was evaluated. RESULTS: Depending upon the depth of ablation and the intensity of charring and carbonization, a standardized energy density and pulse duration were identified. CONCLUSION: Nd:YAG laser with initial delivery of 40-W laser power and a reduced power of 10-15 W thereafter, delivering a total energy density of 1500-2000 J/cm(2) using a bare fiber tip, is recommended for clinical applications.


Assuntos
Disco Intervertebral/efeitos da radiação , Terapia a Laser , Animais , Bovinos , Cães , Relação Dose-Resposta à Radiação , Técnicas In Vitro , Disco Intervertebral/patologia , Deslocamento do Disco Intervertebral/cirurgia , Lasers Semicondutores , Lasers de Estado Sólido , Modelos Animais
7.
J Appl Physiol (1985) ; 107(3): 921-7, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19628727

RESUMO

Several observations suggest that the transmission of myocardial forces is influenced in part by the spatial arrangement of the myocytes aggregated together within ventricular mass. Our aim was to assess, using diffusion tensor magnetic resonance imaging (DT-MRI), any differences in the three-dimensional arrangement of these myocytes in the normal heart compared with the hypertrophic murine myocardium. We induced ventricular hypertrophy in seven mice by infusion of angiotensin II through a subcutaneous pump, with seven other mice serving as controls. DT-MRI of explanted hearts was performed at 3.0 Tesla. We used the primary eigenvector in each voxel to determine the three-dimensional orientation of aggregated myocytes in respect to their helical angles and their transmural courses (intruding angles). Compared with controls, the hypertrophic hearts showed significant increases in myocardial mass and the outer radius of the left ventricular chamber (P < 0.05). In both groups, a significant change was noted from positive intruding angles at the base to negative angles at the ventricular apex (P < 0.01). Compared with controls, the hypertrophied hearts had significantly larger intruding angles of the aggregated myocytes, notably in the apical and basal slices (P < 0.001). In both groups, the helical angles were greatest in midventricular sections, albeit with significantly smaller angles in the mice with hypertrophied myocardium (P < 0.01). The use of DT-MRI revealed significant differences in helix and intruding angles of the myocytes in the mice with hypertrophied myocardium.


Assuntos
Cardiomegalia/patologia , Agregação Celular/fisiologia , Miócitos Cardíacos/patologia , Angiotensina II/farmacologia , Animais , Cardiomegalia/diagnóstico , Cardiomegalia/diagnóstico por imagem , Agregação Celular/efeitos dos fármacos , Imagem de Difusão por Ressonância Magnética , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/efeitos dos fármacos , Ultrassonografia , Vasoconstritores/farmacologia
8.
Neurol India ; 56(1): 22-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18310832

RESUMO

PURPOSE: To evaluate the MR findings in clinically suspected cases of Hirayama disease. MATERIALS AND METHODS: The pre and post contrast neutral and flexion position cervical MR images of eight patients of clinically suspected Hirayama disease were evaluated for the following findings: localized lower cervical cord atrophy, asymmetric cord flattening, abnormal cervical curvature, loss of attachment between the posterior dural sac and subjacent lamina, anterior shifting of the posterior wall of the cervical dural canal and enhancing epidural component with flow voids. The distribution of the above features in our patient population was noted and correlated with their clinical presentation and electromyography findings. OBSERVATIONS: Although lower cervical cord atrophy was noted in all eight cases of suspected Hirayama disease, the rest of the findings were variably distributed with asymmetric cord flattening, abnormal cervical curvature, anterior shifting of the posterior wall of the cervical dural canal and enhancing epidural component seen in six out of eight (75%) cases. An additional finding of thoracic extension of the enhancing epidural component was also noted in five out of eight cases. CONCLUSION: Dynamic post contrast MRI evaluation of cervicothoracic spine is an accurate method for the diagnosis of Hirayama disease.


Assuntos
Imageamento por Ressonância Magnética/métodos , Atrofias Musculares Espinais da Infância/diagnóstico , Atrofias Musculares Espinais da Infância/fisiopatologia , Extremidade Superior/fisiopatologia , Potenciais de Ação/fisiologia , Adolescente , Vértebras Cervicais/patologia , Criança , Humanos , Masculino , Condução Nervosa/fisiologia , Nervos Periféricos/fisiopatologia , Adulto Jovem
9.
Neuroradiology ; 50(2): 105-16, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17929005

RESUMO

INTRODUCTION: Susceptibility-weighted imaging (SWI) is a novel magnetic resonance (MR) technique that exploits the magnetic susceptibility differences of various tissues, such as blood, iron and calcification. This pictorial review covers many clinical conditions illustrating its usefulness. METHODS: SWI consists of using both magnitude and phase images from a high-resolution, three-dimensional fully velocity-compensated gradient echo sequence. Phase mask is created from the MR phase images, and multiplying these with the magnitude images increase the conspicuity of the smaller veins and other sources of susceptibility effects, which is depicted using minimal intensity projection (minIP). RESULTS: The phase images are useful in differentiating between diamagnetic and paramagnetic susceptibility effects of calcium and blood, respectively. This unique MR sequence will help in detecting occult low flow vascular lesions, calcification and cerebral microbleed in various pathologic conditions and aids in characterizing tumors and degenerative diseases of the brain. This sequence also can be used to visualize normal brain structures with conspicuity. CONCLUSION: Susceptibility-weighted imaging is useful in differentiating and characterizing diverse brain pathologies.


Assuntos
Encefalopatias/diagnóstico , Imageamento por Ressonância Magnética , Humanos
10.
Circ Cardiovasc Imaging ; 1(2): 141-7, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19808531

RESUMO

BACKGROUND: Anatomic and functional observations suggest that the right ventricle (RV) can be analyzed in terms of its inlet, apical trabecular, and outlet components. Our study was designed to evaluate the regional adaptation of these components to different conditions of loading, with additional analysis of the surgical techniques used for primary repair. METHODS AND RESULTS: We studied prospectively 45 patients with tetralogy of Fallot (age, 20.5+/-8.1 years) and 24 control subjects (age, 20.1+/-5.8 years). All subjects were studied by using cardiac MRI. End-diastolic (EDV), end-systolic (ESV), stroke volumes (SV), and ejection fraction (EF) were determined for the overall RV and separately for its inlet, apical trabecular, and outlet components. The patients had pulmonary regurgitant fractions of 33.2+/-11.1%, and RV peak-systolic pressures of 40.7+/-16.1 mm Hg. In controls, the apical trabecular component EDV was 51.5+/-11.1 mL/m(2) (54.3+/-6.8% of the total RV EDV), ESV was 19.2+/-6.3 mL/m(2) (47.6+/-10.5% of RV ESV), and SV was 32.3+/-6.9 mL/m(2) (58.9+/-6.6% of RV SV), resulting in an EF of 63.1+/-7.7%. When considering all patients, the apical trabecular component took up the greatest part of the overload, having an EDV of 76.5+/-18.1 mL/m(2), and an ESV of 31.6+/-12.8 mL/m(2), reflecting an increase of 49 and 67% over controls, respectively (P<0.001). EF was 59.7+/-10.7%, and was maintained at control levels (P=0.132). In controls, the outlet had considerable ejecting force, with an EF of 54.8+/-9.1%, whereas it was decreased in the patients with tetralogy (EF=28.5+/-11.9%). There was significant increase of ESV (P<0.001), but not of EDV, with EF decreased by 45% (P<0.001). The inlet was not significantly affected by overload. The surgical technique did not significantly affect any measured parameter for any component. CONCLUSIONS: In patients with tetralogy of Fallot, subsequent to surgical correction, the individual components of the RV respond in characteristic fashion to RV overload.


Assuntos
Imageamento por Ressonância Magnética , Tetralogia de Fallot/fisiopatologia , Função Ventricular Direita , Adolescente , Adulto , Feminino , Implante de Prótese de Valva Cardíaca , Humanos , Masculino , Variações Dependentes do Observador , Valva Pulmonar/cirurgia , Volume Sistólico , Tetralogia de Fallot/cirurgia , Pressão Ventricular , Adulto Jovem
12.
Neuroradiology ; 48(11): 831-9, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16969673

RESUMO

INTRODUCTION: Direct carotid-cavernous fistulae (CCFs) are type A fistulae according to Barrow's classification. Endovascular treatment of these lesions is challenging. METHODS: The purpose of this review was to evaluate the endovascular treatment of direct CCFs. We also describe the technique, symptomatology and complications associated with the procedure and report on the long-term follow-up in our treated patients. RESULTS: A total of 89 patients with a direct CCF were treated. All patients had baseline brain CT or MR imaging. Treatment comprised transarterial balloon or coil embolizations. The patients were followed up at 1 month and then every 6 months thereafter. Detachable balloons were used in 79 fistulae. In 12 fistulae the balloon could not be negotiated through the fistula and these fistulae were treated with transarterial coil occlusion. Clinical outcomes of the treated patients evaluated at 1 month were: 79 patients (88.8%) cured, 9 (10.1%) significantly improved, 1 (1.1%) remaining static. CONCLUSION: Endovascular treatment of direct CCFs is safe and effective and results in long-term cure.


Assuntos
Angioplastia , Oclusão com Balão/métodos , Fístula Carótido-Cavernosa/diagnóstico , Fístula Carótido-Cavernosa/terapia , Embolização Terapêutica/métodos , Adolescente , Adulto , Oclusão com Balão/efeitos adversos , Angiografia Cerebral , Criança , Embolização Terapêutica/efeitos adversos , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Resultado do Tratamento
13.
J Neurosurg ; 105(1): 26-33, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16874888

RESUMO

OBJECT: Vein of Galen malformations (VGMs) are extremely rare intracranial lesions. Clinical presentation and management strategies vary significantly in different areas of the world. The authors report their experience in evaluation, management, and long-term follow up of these lesions in India. METHODS: Between October 1983 and June 2003, 25 patients with VGMs were referred to the authors' institution for evaluation and management. Ten children younger than 2 years of age presented with rapidly increasing head size as the chief complaint. Among 11 children 2 years of age or older, the most common presenting symptom was chronic headache. Four patients who presented during adulthood had chronic headache for many years before presentation. Angiographic evaluation of the lesion was performed in 21 patients. Fifteen patients were treated using endovascular techniques. Injection of the embolic material was performed after induction of systemic hypotension when the flow in the fistula was high. Complete occlusion of the arteriovenous shunt could be achieved in two patients with vein of Galen aneurysmal dilation (100% of patients with this type of malformation) and in five of the six patients with the mural type of malformation (83%). Among patients with the choroidal type of malformation, complete obliteration of the shunt could be achieved in three patients. In three patients with high-flow choroidal malformations, embolization carried out in a single sitting resulted in shunt reduction of nearly 90%. These patients received clinical follow up. CONCLUSIONS: The authors' experience in evaluation and management of VGMs reveals that in areas of the world where access to dedicated specialist care is limited, the clinical presentation of VGMs can differ appreciably from the classic descriptions in the literature. Endovascular management of these lesions results in excellent angiographic and clinical results.


Assuntos
Veias Cerebrais/anormalidades , Embolização Terapêutica , Malformações Arteriovenosas Intracranianas/diagnóstico , Malformações Arteriovenosas Intracranianas/terapia , Adulto , Fatores Etários , Criança , Pré-Escolar , Seguimentos , Humanos , Índia , Lactente , Malformações Arteriovenosas Intracranianas/complicações , Estudos Retrospectivos , Resultado do Tratamento
14.
Neurol India ; 54(2): 164-7, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16804261

RESUMO

BACKGROUND: Low backache (LBA) is now increasing in younger population due to misdirected spinal kinetics secondary to improper posture, heavy load lifting and motorbike driving. Hence minimally invasive procedures are increasingly sought after. Among these, PLDD is currently popular and in use. We present our long term follow-up in the use of Nd:YAG laser for PLDD. AIM: To evaluate the efficacy of PLDD in treatment of contained herniation of lumbar discs & long term follow up results. MATERIALS AND METHODS: Forty patients with contained lumbar disc herniation on MRI and who did not respond to 6 weeks conservative treatment were subjected to PLDD. L4-5 disc was treated in 31, L5-S1 in 12 and L1-2 and L3-4 in one each. Nd:YAG laser at 1064 nm was used for the procedure. Total laser energy of 1500-2000 Joules was delivered at the disc space depending upon the size. RESULTS: There was immediate pain relief in 32/40 (80%). According to MacNab criteria good to fair response was seen in 37/40 (92%) and 3 patients (7.5%) responded poorly to this treatment. On follow up which ranged from 1 to 7 years, 34/40 (85%) had pain relief with no need for further treatment. COMPLICATIONS: Significant pain at local puncture site was experienced by 8 (20%), pain during lasing was experienced by one. One patient developed muscular spasm. CONCLUSION: Percutaneous laser disc decompression is a safe, relatively noninvasive and effective treatment modality for contained, nonsequestered, herniated lumbar disc disease in carefully selected patients.


Assuntos
Descompressão Cirúrgica , Deslocamento do Disco Intervertebral/cirurgia , Procedimentos Neurocirúrgicos , Adulto , Idoso , Dor nas Costas/etiologia , Feminino , Seguimentos , Humanos , Deslocamento do Disco Intervertebral/complicações , Terapia a Laser , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Estudos Retrospectivos
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