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1.
J Med Eng Technol ; 38(4): 220-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24758394

RESUMO

It is sometimes required to shift and/or merge the sampled images for complex perception development in medical and engineering applications. In most cases, for such requirements images are merged at the intensity level. This paper presents a study which shows that intensity level merge is not sufficient enough to analyse certain cases where sharp precision is needed to take a crucial decision. A method has been presented which could be used in precision implant engineering and biological applications like stent placement, where more accurate prediction is required of a combined phenomenon. Accurate merging of intended pixels can be achieved using frequency domain techniques for geometrical and geographical suitability assessment and visualization of post-stenting situation. This paper introduces a technique to merge various images and demonstrates how a surgeon can determine critical midpoint alignment of the stent and visualize the effect of a transplant before actually doing that.


Assuntos
Diagnóstico por Imagem/métodos , Processamento de Imagem Assistida por Computador , Stents , Algoritmos , Humanos
2.
J Med Eng Technol ; 37(7): 429-35, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24015761

RESUMO

Worldwide, health care segment is under a severe challenge to achieve more accurate and intelligent biomedical systems in order to assist healthcare professionals with more accurate and consistent data as well as reliability. The role of ECG in healthcare is one of the paramount importances and it has got a multitude of abnormal relations and anomalies which characterizes intricate cardiovascular performance image. Until the recent past, ECG instruments and analysis played the role of providing the PQRST signal as raw observational output either on paper or on a console or in a file having many diagnostic clues embedded in the signal left to the expert cardiologist to look out for characteristic intervals and to detect the cardiovascular abnormality. Methods and practises are required more and more, to automate this process of cardiac expertise using knowledge engineering and an intelligent systems approach. This paper presents one of the challenging R-peak detections to classify diagnosis and estimate cardio disorders in a fully automated signal processing sequence. This study used an adaptive wavelet approach to generate an appropriate wavelet for R-signal identification under noise, baseband wandering and temporal variations of R-positions. This study designed an adaptive wavelet and successfully detected R- peak variations under various ECG signal conditions. The result and analysis of this method and the ways to use it for further purposes are presented here.


Assuntos
Eletrocardiografia , Análise de Ondaletas , Algoritmos , Arritmias Cardíacas/fisiopatologia , Bases de Dados Factuais , Humanos
3.
Schizophr Res ; 44(1): 11-23, 2000 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-10867308

RESUMO

Recent reports from serial brain scans suggest that the rate of ventricular expansion and/or brain atrophy may be accelerated in at least some schizophrenics. The authors assessed the effect of state changes upon such findings.Within-subject 3D MRIs were assessed for ventricular and brain volumes during periods of [partial] remission and of exacerbation of psychosis. Additional scans at comparable within-subject SAPS were used to assess rates of change in volumes that were independent of SAPS changes. Correlations of changes of ventricle and brain volumes vs. change of SAPS cores between scans revealed that ventricle volumes decreased during a period of psychotic exacerbation and increased at a time of [partial] remission (r(p)=-0.666; P<0.0005); conversely, brain volumes increased during psychotic exacerbation and decreased at [partial] remission (r(p)=+0.448; P=0.032). Scans at comparable SAPS scores suggested that the majority of patients had rates of ventricular expansion comparable to controls (0.9+/-0.6 cc/year), though two patients appeared to have rates of ventricular increase of 4.5+/-2. 1 cc/year (Lilliefores P=0.036; K-means clustering F=17.75). Exacerbation of psychosis in schizophrenia is accompanied by evidence of brain swelling, especially of periventricular brain, with encroachment of brain substance upon ventricular volumes. Controlled for state changes, the majority of schizophrenics show rates of ventricular expansion or brain atrophy indistinguishable from controls.


Assuntos
Encéfalo/patologia , Ventrículos Cerebrais/patologia , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico , Adulto , Atrofia , Edema Encefálico/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Valores de Referência
5.
Neuropsychopharmacology ; 21(1): 82-92, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10379522

RESUMO

The question of whether schizophrenic-like disorders are neurodevelopmental or degenerative in origin has been argued since the time of Kraepelin. The authors provide evidence for the existence of two etiologically distinct endophenotypes of the psychoses contained within the rubric of familial non-affective psychosis (schizophrenia), one atrophic and the other neurodevelopmental. The atrophic psychosis, identified by progressive ventricular enlargement throughout adult illness, evidences progressive impairment of interests, relationships, and withdrawal from latency through adolescence, with emergence of trait-like negative symptoms which are only marginally responsive to conventional neuroleptics. This psychosis also exhibits delayed response of positive symptoms during neuroleptic treatment, and may also proceed to a praecox dementia in later life. In contrast, a putative neurodevelopmental psychosis, associated with static ventricles during the course of adult illness, also demonstrates preadolescent impairments, but impairments which do not progress to marked negative symptoms. Conventional neuroleptics appear to have little effect (except sedation) on positive symptoms, but appear to induce negative symptomatology and partial disengagement from the burden of persistent psychotic thought processes in such static ventricle psychoses. Thus, separate patterns of illnesses with different prodromal features, different treatment response patterns, and different patterns of residual (negative) symptoms appear to characterize patients with psychosis who have expanding as opposed to stable cerebral-ventricles at doses of neuroleptic at 10 mg haloperidol equivalents/day.


Assuntos
Antipsicóticos/uso terapêutico , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Esquizofrenia/tratamento farmacológico , Esquizofrenia/patologia , Psicologia do Esquizofrênico , Adulto , Envelhecimento/fisiologia , Consumo de Bebidas Alcoólicas/patologia , Algoritmos , Atrofia , Ventrículos Cerebrais/patologia , Transtornos Relacionados ao Uso de Cocaína/patologia , Feminino , Haloperidol/uso terapêutico , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
6.
Schizophr Res ; 35(1): 15-23, 1999 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-9988837

RESUMO

A pattern of negative symptoms associated with a high rate of ongoing brain and ventricular instability has been described in a cohort of schizophrenia spectrum probands (patients with schizophrenia, schizoaffective disorder depressed and bipolar, and psychosis NOS) (Garver, D.L., Nair, T.R., Christensen, J.D., Holcomb, J., Ramberg, J., Kingsbury, S., 1999. Differential patterns of premorbid functioning, symptoms and neuroleptic response in stable and unstable ventricular-volume schizophrenia. Neuropsychopharmacology 20, in press). The present study contrasts the prevalence of negative symptoms in first- and second-degree relatives of probands with unstable ventricle volume (UnsVV) and stable ventricle volume (SVV). One hundred and sixteen first- and second-degree relatives of 10 probands were interviewed using the SANS, the 'Characterization of Course: "Pattern of Symptoms"' [from Comprehensive Assessment of Symptoms and History (CASH)], SCID and SCID-II by interviewers blind to the status of the proband. Thirty-five of the 116 family members met DSM-IV criteria for schizophrenia, SA depressed, 'Cluster A' of the SCID-II (paranoid, schizotypal, schizoid personality disorder), psychosis NOS, or psychotic affective disorder. These 35 family members were defined as falling within a 'schizophrenia spectrum' as described by Farmer, A.E., McGuffin, P., Gottesman, I.I., 1987. Arch. Gen. Psychiatry 44, 634-641, but with the addition of DSM-IV affective psychosis. On that basis, the 35 members were considered 'affected family members' (AFMs). The remaining 81 family members were considered unaffected. The 'predominant symptoms of illness' (during the past 2-3 years) for 25 of the 35 AFMs could be characterized according to the 'Patterns of Symptoms' derived from the CASH. Twenty-five of the 35 AFMs were found to maintain a predominant symptom pattern during the course of illness, which could be characterized according to the 'Pattern of Symptoms' as 'predominantly positive' or 'predominantly negative'. Three of the probands had UnsVV; seven had SVV. Of the 35 AFMs, 11 were related to the UnsVV probands, and 24 were relatives of the SVV probands. The nine rated AFMs of the UnsVV probands showed a trend toward higher SANS scores (7.3 +/- 5.1) (mean +/- s.d.) than the 20 rated AFMs of SVV probands (4.3 +/- 5.1) (p = 0.08) at the time of the interview. Eighty-three per cent (eight of 10) of rated affected pedigree members of the pedigrees delineated by probands with UnsVV probands had a predominantly negative symptom course of illness, and 96% (23 of 24) of rated affected pedigree members of the pedigrees with SVV probands had a predominantly positive symptom course of illness during the preceding 2-3 years (p = 0.002). None of the 12 rated affected pedigree members within pedigrees having UnsVV probands were married at the time of the interview; 45% (14 of 31) of affected pedigree members having SVV probands were married (p = 0.004). A psychiatric disorder, characterized by unstable cerebral ventricles and predominant negative symptoms (including avoidance/failure of marital relationships) appears symptomatically to breed true in pedigrees containing schizophrenia-like illnesses.


Assuntos
Ventrículos Cerebrais/anormalidades , Esquizofrenia/genética , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Linhagem , Escalas de Graduação Psiquiátrica , Transtornos Psicóticos/etiologia , Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico
7.
Psychiatry Res ; 74(3): 141-50, 1997 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-9255859

RESUMO

Several anatomic abnormalities in the brains of schizophrenics have frequently been reported. However, it remains unresolved whether such neuropathology is fully expressed and static at the onset of psychosis or whether further deterioration evolves during the course of illness. To address this important question, we obtained serial volumetric magnetic resonance images (MRI) of the cerebral ventricles of 18 patients with schizophrenic symptoms. Repeated blind measurements of total ventricular volume (TVV) revealed < 2% error of the segmentation method. Over a 2-3 year period, the rate of ventricular expansion (RVE) was 2.2 +/- 1.6 cm3/year in the patients and 0.7 +/- 0.6 cm3/year in controls. The RVE in the patients was not normally distributed, but clustered into two groups: a group similar to controls (n = 10; RVE, 0.9 +/- 0.5 cm3/year) and a group with a significantly greater rate of expansion (n = 8; RVE, 3.9 +/- 0.7 cm3/year) (P < 0.001). These results suggest that there are at least two subpopulations within the schizophrenias: one with relatively static ventricles and another with progressively enlarging ventricles. At least two distinct etiologic processes may thus underlie the clinical presentation of schizophrenic symptoms. Factors which might influence ventricular expansion (neuroleptic compliance, alcohol and recreational drug abuse, and some clinical correlates) could not account for differences between groups.


Assuntos
Ventrículos Cerebrais/anatomia & histologia , Imageamento por Ressonância Magnética , Esquizofrenia/diagnóstico , Fatores Etários , Algoritmos , Ventrículos Cerebrais/patologia , Progressão da Doença , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/estatística & dados numéricos , Esquizofrenia/patologia , Software
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