RESUMEN
Cost estimates for care for those with dementia and other cognitive impairments are rising globally, estimated to reach US $1 trillion by 2025. Lack of specialized personnel, infrastructure, diagnostic capabilities, and healthcare access impedes the timely identification of patients progressing to dementia, particularly in underserved populations. International healthcare infrastructure may be unable to handle existing cases in addition to a sudden increase due to undiagnosed cognitive impairment and dementia. Healthcare bioinformatics offers a potential route for quicker access to healthcare services; however, a better preparedness plan must be implemented now if expected demands are to be met. The most critical consideration for implementing artificial intelligence/machine learning (AI/ML) -driven clinical decision intelligence applications (CDIA) is ensuring patients and practitioners take action on the information provided.
RESUMEN
OBJECTIVE: Previous human postmortem experiments have shown an abnormally high number of dopamine uptake sites in the striatum of chronic cocaine users, which might contribute to cocaine withdrawal symptoms such as depression and suicidality. Previous inconsistencies in results were perhaps related to selective radioligand affinity changes or a coexisting loss of dopamine neurons. METHOD: In the present study, binding of the cocaine analog [3H]WIN 35428 to the dopamine transporter was assayed in postmortem striatal samples from 15 cocaine-using subjects and 15 matched comparison subjects to determine whether there were differences in number of binding sites or in affinity. Binding to the vesicular monoamine transporter, a measure of total dopaminergic terminals, was also assessed by using the radioligand (+)-[3H]dihydrotetrabenazine (DTBZ). RESULTS: Striatal [3H]WIN 35428 binding sites were significantly more numerous in the cocaine users: the mean Bmax value was 9.0 fmol bound/microg protein (SD = 2.8) for the cocaine users but only 6.0 (SD = 1.7) for the comparison subjects. Severity of chronic cocaine use was significantly related to [3H]WIN 35428 binding level. [3H]DTBZ binding was significantly lower in the cocaine users (mean = 330 nCi/mg, SD = 42) than in the comparison subjects (mean = 374, SD = 68). CONCLUSIONS: The present results confirm that cocaine users have a high number of dopamine transporter binding sites on dopaminergic neurons, despite an apparent low number of total dopamine terminals. These abnormalities may contribute to the abnormalities in subjective experience and behavior characteristic of chronic cocaine abusers.
Asunto(s)
Trastornos Relacionados con Cocaína/diagnóstico , Cuerpo Estriado/química , Dopamina/análisis , Glicoproteínas de Membrana , Proteínas de Transporte de Membrana , Proteínas del Tejido Nervioso , Receptores Dopaminérgicos/análisis , Adolescente , Adulto , Autorradiografía , Proteínas Portadoras/análisis , Cocaína/análogos & derivados , Trastornos Relacionados con Cocaína/metabolismo , Trastornos Relacionados con Cocaína/psicología , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática , Inhibidores de Captación de Dopamina , Femenino , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , TritioRESUMEN
BACKGROUND: Results of recent radioligand binding experiments suggest that chronic cocaine exposure increases dopamine transporter (DAT) synthesis throughout the striatum of humans. However, detection of cocaine binding site increases in animals and humans has varied depending on the radioligand used. The present experiment tested the hypothesis in cocaine-using humans that synthesis of midbrain DAT messenger RNA increases parallel with increased striatal DAT binding sites. METHODS: Striatal and midbrain samples were collected during autopsy examination from human cocaine users (n = 34) and from age-, sex-, and race-matched control subjects (n = 36). Levels of DAT messenger RNA were quantified in the medial and lateral midbrain regions using in situ hybridization, and striatal DAT binding sites were assessed by quantitative autoradiography using the DAT-specific radioligand [3H]WIN 35428. RESULTS: Striatal DAT binding sites were markedly increased in cocaine users, but, paradoxically, medial DAT messenger RNA levels were decreased. CONCLUSION: Cocaine exposure has a marked effect on DAT function, but the mechanisms involved may be complex.
Asunto(s)
Proteínas Portadoras/análisis , Trastornos Relacionados con Cocaína/metabolismo , Cuerpo Estriado/química , Dopamina/análisis , Glicoproteínas de Membrana , Proteínas de Transporte de Membrana , Proteínas del Tejido Nervioso , Adulto , Animales , Autorradiografía , Sitios de Unión , Química Encefálica , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática , Femenino , Humanos , Hibridación in Situ , Masculino , Persona de Mediana Edad , ARN Mensajero/análisis , RatasRESUMEN
OBJECTIVE: Earlier platelet and postmortem brain studies have found alterations in serotonin transporter function in ethanol-abusing human subjects. The present investigation tested the hypothesis that brain serotonin transporter function is altered in chronic users of ethanol and cocaine, which might be related to a common serotonin transporter promoter polymorphism. METHOD: Serotonin transporter binding sites, serotonin transporter mRNA levels, and serotonin transporter promoter variants were quantified in postmortem samples from a group of human subjects who had been ethanol users or cocaine users and then compared to those of a matched group of comparison subjects. Quantitative autoradiographic and in situ hybridization assays were performed in midbrain samples that contained the dorsal and median raphe nuclei (the location of serotonin cell bodies that innervate the forebrain). RESULTS: There was a significant overall cocaine-by-ethanol-by-genotype interaction. Dorsal raphe [125I]CIT binding to the serotonin transporter was lower in cocaine users than in comparison subjects. In addition, serotonin transporter binding and serotonin transporter mRNA levels varied significantly by genotype. It was also found that serotonin transporter binding in subjects with either the short or heterozygote genotype was significantly higher in the ethanol-user subjects. CONCLUSIONS: Serotonin transporter binding sites were regulated in a region-specific and substance-specific pattern, which was not simply a local response to functional blockade. Also, a reciprocal relationship appeared to exist between cocaine and ethanol effects in the dorsal raphe, which may have interesting clinical implications for dual-diagnosis patients. It is possible that serotonin transporter promoter genotype may play a complex role in chronic ethanol dependence.
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Alcoholismo/metabolismo , Proteínas Portadoras/análisis , Trastornos Relacionados con Cocaína/metabolismo , Glicoproteínas de Membrana/análisis , Proteínas de Transporte de Membrana , Mesencéfalo/química , Proteínas del Tejido Nervioso , Receptores de Serotonina/análisis , Serotonina/análisis , Adulto , Alcoholismo/diagnóstico , Alcoholismo/genética , Autorradiografía , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Trastornos Relacionados con Cocaína/diagnóstico , Trastornos Relacionados con Cocaína/genética , Diagnóstico Dual (Psiquiatría) , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Mesencéfalo/metabolismo , Polimorfismo Genético , ARN Mensajero/análisis , Ensayo de Unión Radioligante , Núcleos del Rafe/química , Núcleos del Rafe/metabolismo , Receptores de Serotonina/metabolismo , Serotonina/genética , Serotonina/metabolismo , Proteínas de Transporte de Serotonina en la Membrana Plasmática , Sustancia Negra/química , Sustancia Negra/metabolismoRESUMEN
This case report describes an accidental death due to the inhalation of tetrachloroethylene during an autoerotic episode. Tetrachloroethylene was administered from a can of Fix-A-Flat tire repair. Analysis of tetrachloroethylene was performed using headspace gas chromatography and electron capture detection. The blood tetrachloroethylene concentration of 62 mg/L was consistent with acute tetrachloroethylene intoxication.
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Trastornos Parafílicos/psicología , Trastornos Relacionados con Sustancias/diagnóstico , Tetracloroetileno/envenenamiento , Administración por Inhalación , Adulto , Autopsia , Resultado Fatal , Medicina Legal , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Masculino , Detección de Abuso de Sustancias , Tetracloroetileno/administración & dosificación , Tetracloroetileno/sangreRESUMEN
Complications associated with the use of cocaine are varied, and include cerebral hemorrhage and ischemia, with vasculitis and vasospasm as possible etiologies. We reviewed selected brain samples from 14 autopsy cases of cocaine-related cerebrovascular disease. Intracerebral or subarachnoid hemorrhage was present in 12 cases. Intracranial arterioles were either normal or showed nonspecific changes. From these observations, we suggest that intracranial hemorrhages occur in the absence of readily detectable vascular abnormalities.
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Arterias Cerebrales/patología , Hemorragia Cerebral/inducido químicamente , Cocaína/efectos adversos , Trastornos Relacionados con Sustancias/complicaciones , Adulto , Arteriolas/patología , Hemorragia Cerebral/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Hemorragia Subaracnoidea/inducido químicamente , Hemorragia Subaracnoidea/patología , Vasculitis/patologíaRESUMEN
The multidisciplinary trauma peer review process collects, reviews, discusses, and collates all morbidities and mortalities of injured patients to institute corrective action in a timely manner. The resultant remedial activity may include professional education, physician counseling, restriction of privileges, or changes in the trauma care system. Effective corrective action necessitates timely data input from the postmortem examination. Faced with an inordinate delay, skimpy reports, and expense in obtaining such reports from the medical examiner's office, the chief medical examiner was invited to become a member of the peer review committee. During a 12-month interval as a full-fledged member of the peer review process, the medical examiner was able to provide complete verbal reports on all deaths resulting in a synergistic benefit to the peer review process and to the medical examiner office. Two of 53 nonpreventable deaths were reclassified as possibly preventable in one and preventable in the other. Four of 15 possibly preventable deaths were reclassified based on the medical examiner report. In turn, the physician members of the team were able to augment the medical examiner's knowledge in certain areas that were critical for his analysis of accidents or homicide. Based on these findings, the medical examiner is recommended as a participating member of the trauma peer review committee.
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Médicos Forenses , Revisión por Expertos de la Atención de Salud , Comité de Profesionales , Heridas y Lesiones/mortalidad , Autopsia , Causas de Muerte , Mortalidad Hospitalaria , Humanos , Garantía de la Calidad de Atención de SaludRESUMEN
Dopamine Transporter (DAT) binding sites in medial temporal lobe structures are much less dense than in striatum and have been difficult to image and quantitate. The recently synthesized compound [125I]RTI-121 ([125I]2 beta-carboxylic acid isopropyl ester-3 beta-(4-iodophenyl)tropane) has demonstrated high specificity and affinity for the DAT in preliminary animal studies. The present experiments were designed to delineate the pharmacological and anatomical characteristics of [125I]RTI-121 binding sites in the striatum and medial temporal lobe of normal humans. A series of saturation experiments performed with striatal membrane preparations generated a one-site model with a KD averaging 1.49 +/- 0.06 nM, and a Bmax that was comparable to those of earlier reports. Competition experiments confirmed the selectivity of [125I]RTI-121 for DAT binding sites. After the assay conditions for autoradiography were optimized, [125I]RTI-121 binding was visualized, pharmacologically characterized and quantitated in human temporal lobe structures. In the hippocampus, specific binding was distributed in the CA4 and CA3 pyramidal cell layers, the outer stratum radiatum and the dentate molecular layer, but not in the dentate granule cells or outer pyramidal cells. In the amygdala specific binding was limited to the basolateral nuclei. Dopamine nerve terminals, as identified with [125I]RTI-121 binding, also displayed a discrete and homologous innervation pattern in the amygdala and hippocampus of several other mammalian species. In summary, the kinetic, saturation, competition and autoradiographic experiments demonstrated that [125I]RTI-121 can be used to identify DAT binding sites and to assess their functional state in post mortem human brain samples.
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Proteínas Portadoras/metabolismo , Cocaína/análogos & derivados , Cuerpo Estriado/metabolismo , Glicoproteínas de Membrana , Proteínas de Transporte de Membrana , Proteínas del Tejido Nervioso , Lóbulo Temporal/metabolismo , Animales , Autorradiografía , Sitios de Unión , Cocaína/metabolismo , Dopamina/metabolismo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática , Cobayas , Humanos , Radioisótopos de Yodo , Masculino , Ratas , Ratas Sprague-DawleyRESUMEN
The prevalence of high grade prostatic intraepithelial neoplasia (HGPIN), the age at which this lesion starts and the potential racial or ethnic differences in its distribution are poorly documented. HGPIN is becoming increasingly implicated as a premalignant lesion for clinically significant prostatic carcinoma (PCa) with mounting evidence linking it to carcinoma according to morphologic immunohistochemical and recent genomic studies. We describe our experience with the age and race distribution of HGPIN resulting from two study populations of African-American (AA) and Caucasian (C) males. The first component of this report describes an autopsy study aimed at determining the prevalence of latent PCa and HGPIN in AA and C men 20 years of age or older; 370 (218 AA and 152 C) consecutive step-sectioned, totally embedded prostate glands were microscopically evaluated and mapped for HGPIN and PCa. HGPIN was first identified in the third decade and increased steadily with age. Latent PCa increased steadily with age with no significant difference in the prevalence between AA and C males in any age group (3rd to 8th decades). HGPIN, on the other hand, was more prevalent in AA men with 18, 31, 69, 78 and 86% in their 4th, 5th, 6th, 7th and 8th decades harboring the lesion. The corresponding figures for C men were 14, 21, 38, 50 and 63% respectively. When HGPIN was quantitated as focal and extensive according to the degree of glandular involvement, extensive HGPIN appeared earlier in AA males under 60 years of age compared to C males cohort. The difference in age distribution appeared to follow a chronological pattern, with HGPIN in AA preceding that of C males by approximately a decade. The second component of this report describes a surgical series of 345 consecutive radical prostatectomies from patients (155 AA and 190 C) with clinically localized PCa, which were thoroughly evaluated microscopically by two urologic pathologists. Similar to the findings in the autopsy study, extensive HGPIN was more prevalent in AA men 60 years of age or younger (57% vs. 33%). In both races, the mean percentage of the gland involved by HGPIN decreased with advancing age in contrast to the mean tumor volume that increased with patient age. These findings indicating a different prevalence of HGPIN in the two racial groups may help explain the higher incidence of prostatic cancer in African-Americans.
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Adenocarcinoma/epidemiología , Negro o Afroamericano/estadística & datos numéricos , Neoplasia Intraepitelial Prostática/epidemiología , Neoplasias de la Próstata/epidemiología , Población Blanca/estadística & datos numéricos , Adenocarcinoma/etnología , Adenocarcinoma/patología , Adulto , Factores de Edad , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Neoplasia Intraepitelial Prostática/etnología , Neoplasia Intraepitelial Prostática/patología , Neoplasias de la Próstata/etnología , Neoplasias de la Próstata/patología , Estados Unidos/epidemiología , Estados Unidos/etnologíaRESUMEN
The relationship of prostatic intraepithelial neoplasia (PIN) and invasive carcinoma of the prostate is not fully understood. It is generally accepted that HGPIN is a probable preinvasive malignant change or at least a marker lesion for carcinoma. The prevalence of HGPIN in younger men is not known. Two hundred and forty nine entirely processed prostates from men aged 20-69 were thoroughly evaluated for the presence of PIN and carcinoma. The histologic diagnosis of all positive cases was confirmed by two pathologists. Our results are summarized as follows: Seventy seven percent of the prostates with HGPIN harbored adenocarcinoma, whereas the frequency of cancer in prostates without HGPIN was 24%. HGPIN was encountered in 0, 5, 10, 41 and 63% of men in the 3rd, 4th, 5th and 7th decades, respectively. The corresponding figures for invasive carcinoma were 2, 29, 32, 55, and 64% respectively.
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Adenocarcinoma/epidemiología , Carcinoma in Situ/epidemiología , Neoplasias de la Próstata/epidemiología , Adenocarcinoma/etnología , Adenocarcinoma/patología , Adulto , Distribución por Edad , Anciano , Autopsia , Población Negra , Carcinoma in Situ/etnología , Carcinoma in Situ/patología , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Neoplasias de la Próstata/etnología , Neoplasias de la Próstata/patología , Población BlancaRESUMEN
BACKGROUND: Children with certain neurologic diseases (hydrocephalus, meningomyelocele, or cerebral palsy) have been reported to manifest a high frequency of A-pattern strabismus and superior oblique overaction. However, it is not generally recognized whether children with strabismus who have superior oblique overaction are more likely to have concurrent neurologic diseases than those without superior oblique overaction. In this study, the authors examine this issue. METHODS: The authors retrospectively reviewed the medical records of all patients (n = 168) with overdepression of the downturned eye in adduction, who were examined between October 1989 and March 1992. A randomly selected population of children with strabismus who did not have overdepression of the eye on infraduction and adduction served as controls (n = 98). Patients with simulating or confounding conditions such as pseudo-superior oblique overaction, inferior rectus skew deviation (alternating skew on lateral gaze), and restrictive or paralytic strabismus, and who were older than 20 years of age, were excluded. RESULTS: One hundred twelve patients with true superior oblique overaction were analyzed. Of these 112 patients, 45 (40.2%) had concurrent neurologic abnormalities, compared with less than one fifth (17.3%) of control subjects (17 of 98) (P < or = 0.001). CONCLUSIONS: Children with strabismus who have superior oblique overaction were found to have higher prevalence of concurrent neurologic diseases than control subjects. Superior oblique overaction may represent a clinical marker for an associated neurologic dysfunction, possibly representing a form of skew deviation in some cases.
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Enfermedades del Sistema Nervioso/complicaciones , Estrabismo/complicaciones , Adolescente , Adulto , Niño , Preescolar , Femenino , Florida/epidemiología , Humanos , Lactante , Masculino , Enfermedades del Sistema Nervioso/epidemiología , Trastornos de la Motilidad Ocular/complicaciones , Trastornos de la Motilidad Ocular/epidemiología , Prevalencia , Distribución Aleatoria , Estudios Retrospectivos , Estrabismo/epidemiologíaRESUMEN
The incidence of clinically detected prostate cancer is increasing with more frequent diagnosis in younger male patients. Whether this represents a genuine increase in incidence or earlier detection is not clear. To understand better the evolution and early changes of prostate cancer we evaluated 152 prostate glands from young male patients 10 to 49 years old. Of the prostates 98 were from African-Americans and 54 were from white patients. Prostatic intraepithelial neoplasia was identified in 0%, 9%, 20 and 44%, and small foci of histological cancer in 0%, 0%, 27% and 34% of the male patients in the second, third, fourth and fifth decades of age, respectively. The majority of the cases of prostatic intraepithelial neoplasia were of low grade. High grade prostatic intraepithelial neoplasia, found in 5 prostates, was first identified in the fifth decade. All 5 cases occurred in prostates containing histological carcinoma. Incidental carcinoma was detected with a similar frequency in white and black patients. The cancerous foci were of similar size with a tendency for cancer in black patients to be multifocal, particularly in those in the fifth decade. We conclude that prostatic intraepithelial neoplasia and histological cancers are surprisingly common in young male patients of both races. The evolution of prostatic intraepithelial neoplasia and focal histological cancers is not clear but it appears to present several decades earlier than clinically detected carcinoma. The natural history of prostate cancer must encompass many more years (decades) than has been previously realized. In addition, the initiating events leading to clinically relevant prostate cancers likely occur at a remarkably young age.
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Neoplasias de la Próstata/patología , Adenocarcinoma/diagnóstico , Adenocarcinoma/patología , Adolescente , Adulto , Factores de Edad , Carcinoma/patología , Niño , Humanos , Masculino , Persona de Mediana Edad , Próstata/patología , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/epidemiología , Grupos RacialesRESUMEN
The dopamine transporter is the primary means of inactivating synaptic dopamine as well as a major site of action for psychostimulants (such as cocaine and amphetamine) and for neurotoxins that induce parkinsonism. In the present study, a human dopamine transporter partial cDNA clone obtained by polymerase chain reaction exhibited 87% and 89% identity at the nucleic acid and amino acid levels, respectively, with transmembrane domains 3-5 of the rat homolog. This clone was used to quantitate human dopamine transporter mRNA by nuclease protection assay. The postmortem content of dopamine transporter mRNA in the substantia nigrae of 18- to 57-yr-old subjects was relatively constant, while in subjects greater than 57 yr old, a precipitous (greater than 95%) decline in substantia nigra dopamine transporter mRNA was evident. In contrast, tyrosine hydroxylase mRNA in the same samples declined in a linear manner with increasing age. In situ hybridization experiments confirmed the profound loss of dopamine transporter gene expression in melanin-positive (presumptive dopamine) nigral neurons. These data may begin to shed light on compensatory changes occurring in human dopamine neurons during normal aging.
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Envejecimiento/fisiología , Proteínas Portadoras/genética , Glicoproteínas de Membrana , Proteínas de Transporte de Membrana , Proteínas del Tejido Nervioso , ARN Mensajero/metabolismo , Sustancia Negra/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Secuencia de Aminoácidos , Secuencia de Bases , Dopamina/metabolismo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática , Expresión Génica , Humanos , Persona de Mediana Edad , Datos de Secuencia Molecular , Neuronas/fisiología , Oligodesoxirribonucleótidos , Oligonucleótidos Antisentido , ARN Mensajero/genética , Sustancia Negra/crecimiento & desarrollo , Tirosina 3-Monooxigenasa/genéticaRESUMEN
Binding of normal human IgG to embryonic rat brain neurons was quantitated by flow cytometry. IgG binding was linear between 0.05 and 1.5 mg/ml; slight binding was detectable even at normal cerebrospinal fluid concentrations. Similar binding curves were obtained for purified Fc and F(ab')2 fragments from normal human IgG. Normal human IgG also bound to synaptosomes (resealed nerve terminals) from human cerebral cortex. However, competition assays utilizing 125I-IgG showed no evidence for specific binding. This study indicates that the specificity of putative anti-neuronal antibodies should be confirmed by competition assays as for other receptor-ligand binding.
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Encéfalo/metabolismo , Feto/metabolismo , Fragmentos Fab de Inmunoglobulinas/metabolismo , Inmunoglobulina G/metabolismo , Neuronas/metabolismo , Sinaptosomas/metabolismo , Animales , Encéfalo/citología , Encéfalo/embriología , Corteza Cerebral/metabolismo , Humanos , Fragmentos Fc de Inmunoglobulinas/metabolismo , Ratas/embriología , Factores de TiempoRESUMEN
The medicolegal implications of a delayed subdural hemorrhage are described, with particular reference to the significance of the alcohol content in the hematoma versus that in the peripheral blood at the time of injury.
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Etanol/metabolismo , Hematoma Subdural/metabolismo , Accidentes de Tránsito , Adulto , Intoxicación Alcohólica , Femenino , Medicina Legal , Humanos , Factores de TiempoRESUMEN
At the present rate of training, physician extenders will shortly make up a substantial fraction of eye care providers. However, there have not yet been any published studies on the impact of this group on the delivery of services. It is the purpose of this article to outline the training categories and requirements now available for physician extenders in ophthalmology and to obtain direct feedback from ophthalmologists regarding current utilization and potential need for such personnel. Readers are asked to complete a questionnaire, which will serve as the basis for a future report on this subject.
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Asistentes de Oftalmología/estadística & datos numéricos , Asistentes Médicos/estadística & datos numéricos , Certificación , Competencia Clínica , Humanos , Asistentes de Oftalmología/educación , Asistentes de Oftalmología/provisión & distribución , Salarios y Beneficios , Estados UnidosRESUMEN
A group of 238 patients with cerebral palsy were identified of whom 108 could be studied through their charts. Only 20 of these patients had strabismus. Of this group, 10 received no surgical therapy. In these patients followed up to a period of four years, no evidence of significant change in the strabismic deviation was found. Patients who were treated by medical and optical means alone did not show evidence of improvement. Surgical therapy was effective in providing a cosmetically acceptable result. Surgery was performed between two and one-half and 13 years of age in eight patients, with an average age of surgery of 6.5 years. The results which we obtained are comparable to those obtained by others at an earlier age. It does not appear that the age of surgery affects the ultimate cosmetic nor functional outcome in children with cerebral palsy.