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1.
Am J Dermatopathol ; 34(5): 461-70, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21993337

RESUMEN

BACKGROUND: Hidradenomas are rare benign adnexal neoplasms that encompass a morphological gamut with a range of differentiation. As a consequence, there is a great likelihood of being mistaken for other primary and metastatic tumors. Though conventionally regarded as eccrine, they have been reclassified into eccrine and apocrine types. OBJECTIVE: This study aims to document the histological spectrum of nodular hidradenomas, with particular reference to categorizing them into eccrine or apocrine tumors. RESULTS: A total of 15 cases with features of nodular hidradenoma with their age ranging from 18 years to 73 years were studied. Most of the cases were solitary, circumscribed, solid and cystic, dermal, symmetrical, lobulated tumors with a sheet-like and papillary architecture. The cells were chiefly eosinophilic with a regular oval grooved nucleus and a small inconspicuous nucleolus. Clear cells were also seen. Squamous differentiation was an important feature, with most showing a infundibular type of keratinization. Sebaceous differentiation is also common. The stroma varied from hyaline to myxoid. Only 1 case showed poroid differentiation. CONCLUSIONS: This study describes the assortment of histologic characteristics in hidradenomas. Apocrine hidradenomas are more common, contrary to earlier belief that favored an eccrine origin.


Asunto(s)
Acrospiroma/patología , Glándulas Apocrinas/patología , Glándulas Ecrinas/patología , Neoplasias de las Glándulas Sudoríparas/patología , Acrospiroma/clasificación , Adolescente , Adulto , Anciano , Biopsia , Diferenciación Celular , Femenino , Humanos , India , Masculino , Persona de Mediana Edad , Células del Estroma/patología , Neoplasias de las Glándulas Sudoríparas/clasificación , Adulto Joven
2.
Proc Inst Mech Eng H ; 236(6): 882-895, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35337232

RESUMEN

Single-channel Electrooculogram (EOG) is proposed for detecting diabetic retinopathy. The Corneal-retinal potential of the eyes plays a vital role in the acquisition of Electrooculography. Diabetes is the most prevalent disease and for one out of three people with diabetes above 40 years, diabetic retinopathy occurs. It is necessary for the early detection of diabetic retinopathy as it is one of the primary reasons for blindness in the population. The potential difference between cornea and retina leads to the acquisition of EOG signal. The proposed study aims to design a low-cost miniaturized hardware circuit to obtain EOG signal using second order filters without compromising in accuracy of the outcome signal and to classify the signal into normal and diabetic retinopathy subjects by extracting the statistical features like kurtosis, mean, median absolute deviation, standard deviation, and range from software filtered EOG signal. Among the classifiers used, Support vector machine (SVM) shows a higher accuracy of 93.33%. The sensitivity, specificity and Area Under Curve (AUC) values of SVM are 96.43%, 90.625%, 0.93% is considered as more favorable outcome for the proposed method and it supports the developed prototype and processing methodology. The novelty of the research is based on proposing and exploring a non-invasive methodology for Diabetic retinopathy diagnosis based on EOG signal. Thus, the designed hardware is simple in operation and cost effective, provides an affordable and non-invasive diagnostic tool for diabetic retinopathy patients.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Retinopatía Diabética/diagnóstico , Electrooculografía , Humanos , Aprendizaje Automático , Retina , Máquina de Vectores de Soporte
3.
Comput Math Methods Med ; 2022: 8723957, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36404909

RESUMEN

Colorectal cancer typically affects the gastrointestinal tract within the human body. Colonoscopy is one of the most accurate methods of detecting cancer. The current system facilitates the identification of cancer by computer-assisted diagnosis (CADx) systems with a limited number of deep learning methods. It does not imply the depiction of mixed datasets for the functioning of the system. The proposed system, called ColoRectalCADx, is supported by deep learning (DL) models suitable for cancer research. The CADx system comprises five stages: convolutional neural networks (CNN), support vector machine (SVM), long short-term memory (LSTM), visual explanation such as gradient-weighted class activation mapping (Grad-CAM), and semantic segmentation phases. Here, the key components of the CADx system are equipped with 9 individual and 12 integrated CNNs, implying that the system consists mainly of investigational experiments with a total of 21 CNNs. In the subsequent phase, the CADx has a combination of CNNs of concatenated transfer learning functions associated with the machine SVM classification. Additional classification is applied to ensure effective transfer of results from CNN to LSTM. The system is mainly made up of a combination of CVC Clinic DB, Kvasir2, and Hyper Kvasir input as a mixed dataset. After CNN and LSTM, in advanced stage, malignancies are detected by using a better polyp recognition technique with Grad-CAM and semantic segmentation using U-Net. CADx results have been stored on Google Cloud for record retention. In these experiments, among all the CNNs, the individual CNN DenseNet-201 (87.1% training and 84.7% testing accuracies) and the integrated CNN ADaDR-22 (84.61% training and 82.17% testing accuracies) were the most efficient for cancer detection with the CNN+LSTM model. ColoRectalCADx accurately identifies cancer through individual CNN DesnseNet-201 and integrated CNN ADaDR-22. In Grad-CAM's visual explanations, CNN DenseNet-201 displays precise visualization of polyps, and CNN U-Net provides precise malignant polyps.


Asunto(s)
Neoplasias Colorrectales , Pólipos , Humanos , Redes Neurales de la Computación , Máquina de Vectores de Soporte , Diagnóstico por Computador/métodos , Colonoscopía , Neoplasias Colorrectales/diagnóstico por imagen
4.
Sci Rep ; 12(1): 17417, 2022 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-36257964

RESUMEN

The objectives of our proposed study were as follows: First objective is to segment the CT images using a k-means clustering algorithm for extracting the region of interest and to extract textural features using gray level co-occurrence matrix (GLCM). Second objective is to implement machine learning classifiers such as Naïve bayes, bagging and Reptree to classify the images into two image classes namely COVID and non-COVID and to compare the performance of the three pre-trained CNN models such as AlexNet, ResNet50 and SqueezeNet with that of the proposed machine learning classifiers. Our dataset consists of 100 COVID and non-COVID images which are pre-processed and segmented with our proposed algorithm. Following the feature extraction process, three machine learning classifiers (Naive Bayes, Bagging, and REPTree) were used to classify the normal and covid patients. We had implemented the three pre-trained CNN models such as AlexNet, ResNet50 and SqueezeNet for comparing their performance with machine learning classifiers. In machine learning, the Naive Bayes classifier achieved the highest accuracy of 97%, whereas the ResNet50 CNN model attained the highest accuracy of 99%. Hence the deep learning networks outperformed well compared to the machine learning techniques in the classification of Covid-19 images.


Asunto(s)
COVID-19 , Aprendizaje Profundo , Humanos , COVID-19/diagnóstico por imagen , Teorema de Bayes , Aprendizaje Automático , Tomografía Computarizada por Rayos X , Pulmón/diagnóstico por imagen
5.
Proc Inst Mech Eng H ; 235(10): 1128-1145, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34176352

RESUMEN

Thyroid is a butterfly shaped gland located in the neck region. Hormones are secreted by the thyroid gland that is responsible for various functions that maintain metabolism of the body. The variance in secretion of the hormones causes disorders such as Hyperthyroidism or Hypothyroidism. Electroglottography signal is a bio signal which represents the impedance that exist between the glottis regions. The study aims at design and development of an hardware circuit for the acquisition of Electroglottogram signal from normal and thyroid subjects is proposed followed by feature extraction from the acquired bio signal is performed. Further, machine learning classifiers were used to classify the normal and thyroid individuals. This modality of acquisition is non-invasive. Performance evaluation is done by testing various classifiers to study the accuracy. The classifiers tested were Random Forest, Random Tree, Bayes Net, Multilayer Perceptron, Simple Logistic classifier, and One-R classifier. Classifiers such as Random Forest, Random Tree, and Multilayer Perceptron showed high accuracy. The accuracy estimated by these classifiers was tested and its ROC curves with AUC scores were derived. The highest accuracy was reported for Simple Logistic classifier which was about 95.1%. Random Forest and Random Tree reported 93.5% and 91.9% respectively. Similarly, Multilayer Perceptron and Bayes Net gave 93.5% and 91.9%. The One-R classifier algorithm reported the lowest accuracy of 90.3% among the studied classifier algorithms. The ROC-AUC score for the classifiers were also reported to be more than 0.9 which is considered more promising and supports the acquisition and processing methodology. Hence the proposed technique can be efficiently used to diagnose thyroid non-invasively.


Asunto(s)
Aprendizaje Automático , Glándula Tiroides , Algoritmos , Teorema de Bayes , Humanos , Curva ROC , Máquina de Vectores de Soporte
6.
Biomed Tech (Berl) ; 64(3): 285-295, 2019 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-30055095

RESUMEN

The physiological modeling of retinal layers to provide an insight into how the incoming image is converted into its equivalent spike train that can be decoded by the human brain is a key issue. Most of the retinal layer models concentrate mainly on image compression, edge detection and image reconstruction. A retinal layer model to generate spike waveform corresponding to the visual information is not covered much in the literature. The aim of this study was to develop a mathematical model of retinal layers that has complex neural structures, that can detect the incoming signal and transform the signal into the equivalent spike train. The proposed retinal layer model includes a photoreceptor, an outer plexiform (OPL), an inner plexiform (IPL) and ganglion cell layers exhibiting the properties of compression, luminance and spatial temporal filtering in the processing of visual information. The photoreceptor layer enhances the contrast visibility in the dark region and maintains the same in the bright regions. The OPL is modeled to enhance the contour of the image. The finer detail of the image is extracted by mathematically modeling the IPL. The ganglion cell layer is modeled using the Hodgkin-Huxley model to generate the spike train for the incoming information. The spike train was generated for color deficient individuals namely protanopia, deuteranopia, tritanopia and for individuals suffering from night blindness. Simulation results showed a spike train was generated only for a certain threshold stimulus value. The differences in spike pattern for a normal and visually impaired individual were studied. This may lead to a methodology for earlier diagnosis.


Asunto(s)
Retina/fisiología , Estrabismo/fisiopatología , Color , Humanos
7.
Indian J Surg Oncol ; 9(4): 592-594, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30538395

RESUMEN

Multiple primary cancer (MPC) has an incidence of 1.8% and is defined as having two or more cancers in a single patient. Synchronous tumors are defined as ≥ 2 primary tumors occurring within 6 months of diagnosis of the first primary tumor. We present a case of a 27-year-old female patient who presented with a painless, gradually progressive right-sided neck swelling for the last 1 year with no systemic complaints. Examination revealed a 4 × 3-cm, firm, smooth surfaced swelling on right lobe of thyroid. USG neck showed a hypoechoic solid nodule on the right lobe and the left lobe was normal. FNAC showed features of adenomatous colloid nodule, Bethesda II. Right hemithyroidectomy specimen revealed evidence of triple tumors-not otherwise-specified (NOS) tumor, papillary carcinoma thyroid, and medullary carcinoma thyroid, which was confirmed with positivity on IHC with synaptophysin, CEA, and chromogranin. Concurrent appearance of NOS, PTC, and medullary carcinoma thyroid in the very same patient is extremely rare and has not been previously reported in the English literature.

8.
Biofactors ; 30(4): 217-25, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18607071

RESUMEN

Urinary catheterization is a routine procedure in an intensive care unit (ICU) for monitoring the urine output of critically ill patients. The catheters which are most often used to help with urinary incontinence and retention also face problems like blockage, leakage and infection. These problems are due to proteins that adhere to the catheter surface and quickly build up on each other forming a protein layer. As the layers build up they can crystallize, providing the major source of blockage and leakage. Current strategies to avoid these problems include coating a catheter with silver alloy to reduce bacteria on the catheter surface. However, silver alloy coatings can lead to increased silver resistance for bacteria. Since silver is already used as an antibacterial agent in many places in a hospital, it is even more possible that resistance can develop. An alternative solution is presented involving coating latex, a common urinary catheter material with a micro layer (5-100 microns) of polyethylene glycol. This hydrogel is applied using an interfacial photopolymerization process with ethyl eosin as the photoinitiator. A 25 ppm concentration of ethyl eosin provided the strongest gel to surface adhesion and significantly lowered protein adhesion when compared to an uncoated latex substrate.


Asunto(s)
Hidrogeles/química , Polietilenglicoles/química , Cateterismo Urinario/efectos adversos , Adsorción , Materiales Biocompatibles Revestidos/síntesis química , Eosina Amarillenta-(YS)/análogos & derivados , Eosina Amarillenta-(YS)/química , Látex/química , Proteínas/química , Cateterismo Urinario/instrumentación
9.
Indian J Pathol Microbiol ; 50(4): 730-2, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18306538

RESUMEN

UNLABELLED: Direct Immunofluorescence (DIF) is invaluable in the diagnosis of cutaneous vesiculobullous lesions (VBL). It is limited by technical factors and disease nature. 1) To record the sensitivity of DIF in VBL 2) To correlate DIF with clinical, histologic findings and analyse discrepancies. MATERIAL AND METHODS: A retrospective study of 100 DIFs on suspected VBL of skin. DIF, histology and clinical data were reviewed. 73/100 cases showed DIF patterns concordant with clinical/histologic diagnosis. The sensitivity of DIF was 88% in Pemphigus group (39/ 44), 82% in Bullous Pemphigoid (BP) (23/28), and 20% in Dermatitis Herpetiformis (DH) (1/5).18 cases of histologically proven VBL were negative and of these, 4 had no epidermis. The remaining 9 cases were discordant with clinical/histologic features, including 4 BP and 5 DH, whose histology was non-specific and will be discussed in detail. One case of DH showed an aberrant vasculitic pattern. DIF is of great value in the diagnosis of VBL, specially in clinical/histologic dilemmas. In DH, neither biopsy nor DIF were very useful and response to therapy was the standard. Sampling errors contributed to false negative results. Proper selection of cases and judicious use are mandatory to optimize its' utility.


Asunto(s)
Técnica del Anticuerpo Fluorescente Directa/métodos , Enfermedades Cutáneas Vesiculoampollosas/diagnóstico , Piel/patología , Dermatitis Herpetiforme/diagnóstico , Dermatitis Herpetiforme/patología , Humanos , Penfigoide Ampolloso/diagnóstico , Penfigoide Ampolloso/patología , Pénfigo/diagnóstico , Pénfigo/patología , Estudios Retrospectivos , Sensibilidad y Especificidad , Enfermedades Cutáneas Vesiculoampollosas/patología , Enfermedades Cutáneas Vesiculoampollosas/fisiopatología
10.
Proc Inst Mech Eng H ; 231(4): 276-285, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28195004

RESUMEN

Physiological modeling of retina plays a vital role in the development of high-performance image processing methods to produce better visual perception. People with normal vision have an ability to discern different colors. The situation is different in the case of people with color blindness. The aim of this work is to develop a human visual system model for detecting the level of perception of people with red, green and blue deficiency by considering properties like luminance, spatial and temporal frequencies. Simulation results show that in the photoreceptor, outer plexiform and inner plexiform layers, the energy and intensity level of the red, green and blue component for a normal person is proved to be significantly higher than for dichromats. The proposed method explains with appropriate results that red and blue color blindness people could not perceive red and blue color completely.


Asunto(s)
Percepción de Color , Defectos de la Visión Cromática/fisiopatología , Modelos Biológicos , Defectos de la Visión Cromática/diagnóstico , Defectos de la Visión Cromática/patología , Humanos , Células Fotorreceptoras/patología
11.
Proc Inst Mech Eng H ; 231(12): 1178-1187, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29076764

RESUMEN

The aim and objectives of the study are as follows: (1) to perform automated segmentation of knee X-ray images using fast greedy snake algorithm and feature extraction using gray level co-occurrence matrix method, (2) to implement automated segmentation of knee thermal image using RGB segmentation method and (3) to compare the features extracted from the segmented knee region of X-ray and thermal images in rheumatoid arthritis patients using a biochemical method as standard. In all, 30 rheumatoid arthritis patients and 30 age- and sex-matched healthy volunteers were included in the study. X-ray and thermography images of knee regions were acquired, and biochemical tests were carried out subsequently. The X-ray images were segmented using fast greedy snake algorithm, and feature extractions were performed using gray level co-occurrence matrix method. The thermal image was segmented using RGB-based segmentation method and statistical features were extracted. Statistical features extracted after segmentation from X-ray and thermal imaging of knee region were correlated with the standard biochemical parameters. The erythrocyte sedimentation rate shows statistically significant correlations (p < 0.01) with the X-ray parameters such as joint space width and % combined cortical thickness. The skin surface temperature measured from knee region of thermal imaging was highly correlated with erythrocyte sedimentation rate. Among all the extracted features namely mean, variance, energy, homogeneity and difference entropy depict statistically significant percentage differences between the rheumatoid arthritis and healthy subjects. From this study, it was observed that thermal infrared imaging technique serves as a potential tool in the evaluation of rheumatoid arthritis at an earlier stage compared to radiography. Hence, it was predicted that thermal imaging method has a competency in the diagnosis of rheumatoid arthritis by automated segmentation methods.


Asunto(s)
Artritis Reumatoide/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Rodilla/diagnóstico por imagen , Radiografía , Temperatura , Automatización , Humanos
12.
J Pharm Bioallied Sci ; 7(Suppl 1): S197-9, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26015708

RESUMEN

DNA adduct is a piece of DNA covalently bond to a chemical (safrole, benzopyrenediol epoxide, acetaldehyde). This process could be the start of a cancerous cell. When a chemical binds to DNA, it gets damaged resulting in abnormal replication. This could be the start of a mutation and without proper DNA repair, this can lead to cancer. It is this chemical that binds with the DNA is our prime area of concern. Instead of performing the whole body analysis for diagnosing cancer, this test could be carried out for early detection of cancer. When scanning tunneling microscope is used, the DNA results can be obtained earlier. DNA adducts in scientific experiments are used as biomarkers.

13.
Oncol Rep ; 3(6): 1195-8, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21594538

RESUMEN

Cell proliferation is an important biological aspect of a tumor cell population which can affect clinical outcome. In addition to other well established clinical and histopathological prognostic criteria? cell kinetic data have significant predictive value. This study evaluates the proliferative activity of benign, premalignant and malignant cervical tissue by analyzing the expression of the proliferating cell nuclear antigen (PCNA). PCNA is a 36 kD nuclear protein associated with the cell cycle and is directly involved in DNA synthesis during cell proliferation. A total of 122 subjects were included in the study. This included 30 benign tissue samples, 30 low grade lesions (CIN 1), 30 high grade lesions (CIN 2/3) and 32 invasive squamous carcinomas. There was significant difference in PCNA index between benign and high grade lesions as well as benign and invasive cancer. The percentage of PCNA positive cells were significantly higher in invasive carcinoma when compared with non malignant lesions. Moreover, there was also good correlation between increasing histological abnormality and PCNA expression. These results suggest that cell proliferation index as detected by PCNA expression may be useful in the evaluation of alterations in cell kinetics of various grades of cervical lesions. Such data could also possibly help explain the biological behaviour of these lesions and be useful in planning of radiotherapy for invasive cervical cancer.

14.
Indian J Cancer ; 35(4): 147-51, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10388229

RESUMEN

When colonic carcinomas present with acute abdomen, the operating surgeon and the pathologist face a plethora of diagnostic and therapeutic problems. In this retrospective study of 92 cases of carcinoma colon, 4 presented with acute intestinal obstruction of which three had a turbulent post operative period and died. The resected colonic segment showed on gross examination cobblestone appearance characteristic of Crohn's disease but microscopically was ischemic with the stricture site showing features of an infiltrating poorly differentiated adenocarcinoma. We have made an attempt to study the various pathologic features and analyse their significance with reference to prognosis.


Asunto(s)
Adenocarcinoma/patología , Neoplasias del Colon/patología , Enfermedad de Crohn/patología , Adolescente , Adulto , Diagnóstico Diferencial , Humanos
15.
Indian J Pediatr ; 70(10): 839-41, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14649485

RESUMEN

Intestinal neuronal dysplasia is a rare cause of bowel obstruction in neonates and infants, the diagnosis of which poses a formidable challenge to both clinicians and pathologists alike. The importance of this entity lies not only in the fact that it mimics Hirschsprung's disease, but also in that untreated cases, particularly of type A, may prove fatal. The authors describe one such case of intestinal neuronal dysplasia of type A, which was diagnosed at autopsy.


Asunto(s)
Enfermedad de Hirschsprung/patología , Obstrucción Intestinal/patología , Resultado Fatal , Femenino , Humanos , Hipertrofia/patología , Lactante , Fibras Nerviosas/patología , Nervios Periféricos/patología
16.
Indian J Pathol Microbiol ; 57(1): 127-9, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24739851

RESUMEN

Skin is one of the important organs affected by amyloidosis which is characterized by extracellular deposition of fibrillary proteins having homogenous, eosinophilic on routine staining with distinct tinctorial properties. Nodular cutaneous amyloidosis is rare and may affect dermis, subcutis and also vascular walls. Nodular amyloid deposits in the deeper dermis occurring at the site of insulin injection are a rare observation, which is described here. This description indicates that cutaneous amyloidosis may be associated with local subcutaneous injections of insulin and may clinically mimic a neoplasm or lipodystrophic lesion.


Asunto(s)
Acantosis Nigricans/complicaciones , Acantosis Nigricans/diagnóstico , Amiloidosis/complicaciones , Amiloidosis/diagnóstico , Inyecciones Subcutáneas/efectos adversos , Insulina/administración & dosificación , Acantosis Nigricans/patología , Amiloidosis/patología , Histocitoquímica , Humanos , Masculino , Microscopía , Persona de Mediana Edad , Piel/patología
18.
Indian J Urol ; 27(4): 545-6, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22279327

RESUMEN

Actinomycosis is a chronic inflammatory condition caused by Actinomyces israeli, a gram positive anaerobic bacterium. It can have a variety of clinical manifestations and can mimic a malignancy. We present one such case of urachal actinomycosis that mimicked a tumor. A 28-year-old man presented with abdominal pain of 20 days duration. Per abdominal palpation revealed a firm mass with ill-defined borders in the suprapubic region. Computed tomography and magnetic resonance imaging scans of the pelvis showed an irregular lesion in the urinary bladder extending to the umbilicus, giving the impression of urachal remnants with inflammation. Peroperatively, an irregular, hard mass measuring 6 × 5 cm, involving the anterior and posterior bladder walls, the appendix, the terminal ileum and sigmoid colon, was seen, which was suspicious for a malignancy. Frozen sections from the mass showed extensive inflammation and a florid fibroblastic proliferation, giving the impression of an inflammatory pseudotumor. The tissue was extensively sampled for paraffin sections and only one of them revealed a colony of Gram, PAS and GMS- positive organisms, conclusive for Actinomycosis. It is important to be aware of this uncommon, yet significant, presentation of a common infectious disease in order to avoid misdiagnosis and over-treatment as a malignancy.

19.
Int J Trichology ; 2(1): 14-7, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21188017

RESUMEN

BACKGROUND: Alopecia Areata (AA) is a "non-scarring" alopecia that has an autoimmune basis. Though clinically distinctive, problems arise in diagnosis depending on the temporal stage of the disease at presentation; some of them progress to scarring alopecia and predicting its prognosis is difficult. Histological changes depend on the disease stage and site of the biopsy. OBJECTIVES: To describe the spectrum of histologic features in AA. MATERIALS AND METHODS: A prospective and retrospective study of H and E sections of all biopsies signed out as AA between 2001 and 2009 (20 cases) was undertaken. RESULTS: The diagnosis was made on vertical sections in all cases. The total number of hair follicles ranged from 1 to 24 with an average of 7 and comprised mainly terminal follicles. Vellus follicles were scanty. Anagen to non-anagen ratio was 1:1.62. Miniaturization of follicles was noted in five (25%) cases. Peribulbar inflammation was seen in all the cases with a dominance of lymphocytes. Perifollicular fibrosis was noted in 12 (60%) and pigment casts in 5 (25%) cases. Scarring was seen in two cases. In these cases, a diagnosis of AA was rendered on the basis of even spacing of the fibrotic units and remnants of the catagenic basement membrane within the scars. The epidermis and interfollicular dermis were normal in all the cases. CONCLUSION: The most consistent features of AA are an increase in non-anagen terminal follicles and peribulbar lymphocytic infiltrate. The etiology can be determined even in cases that have progressed to scarring.

20.
Artículo en Inglés | MEDLINE | ID: mdl-20826995

RESUMEN

BACKGROUND: Pilomatricoma is a benign tumor of hair matrix differentiation and has been classically described as comprising of basaloid and shadow cells admixed with multinucleated giant cells and areas of calcification. However, there are a diverse range of histologic features this tumor displays that are often unrecognized. AIMS: This study was undertaken to record the histopathologic features of pilomatricoma with an emphasis on the occurrence of other forms of differentiation. METHODS: The study included all skin biopsy specimens over a 13-year period from 1995 to 2007 that had a histologic diagnosis of pilomatricoma. Hematoxylin and eosin-stained slides were reviewed. RESULTS: This study included 21 cases of pilomatricoma. Supramatrical differentiation was seen in all cases and three-quarters of the cases showed matrical differentiation. Also observed in some of the cases were clear cell differentiation toward the outer root sheath, infundibular differentiation, calcification, ossification and secondary inflammation with a foreign body giant cell reaction. Epidermal induction in the form of a downward plate-like growth of the epidermis was seen in a few cases. CONCLUSION: Pilomatricoma, although considered a tumor of hair matrix differentiation, can show cellular evolution toward the other parts of the hair follicle, such as the outer and inner root sheaths, sebaceous and infundibular components and, therefore, can be considered a panfollicular neoplasm.


Asunto(s)
Enfermedades del Cabello/patología , Folículo Piloso/patología , Cabello/patología , Pilomatrixoma/patología , Neoplasias Cutáneas/patología , Adolescente , Adulto , Biopsia , Diferenciación Celular , Niño , Femenino , Humanos , Masculino , Adulto Joven
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