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AIM: In recent years, various professional societies published guidelines for diagnostic evaluation of thyroid nodules, in which the indication for scintigraphy is restricted to patients with subnormal TSH values. It is seen controversial whether such recommendations should be transferred to Germany, partly because of lower iodine intake in this country and the consequent higher percentage of autonomous thyroid nodules, which are not accompanied by a measurable dysfunction. Since reliable data to this topic are scarce, we analyzed multicentrically the spectrum of scintigraphically "hot" and "warm" nodules under the current epidemiological conditions. PATIENTS, METHODS: In 10 German nuclear medicine out-patient institutions we evaluated the diagnostic data from a total of 514 patients, in whom unequivocally hyperfunctional nodules (focal increased uptake in comparison to perinodular tissue with a sonographically nodular correlative ≥1 cm) could be detected by (99m)Tc-pertechnetate scintigraphy. To minimize selection bias, the surveys were not carried out in hospitals.The recorded parameters included the thyroid hormone levels, the global (99m)Tc-uptake (TcTU), the size of each nodule and the total autonomous nodular volume (V(aut)). RESULTS: Only 20% of the patients with "hot" nodules had subnormal TSH levels (<0.1 to 0.33 mU / l), the remaining patients had TSH levels from 0.34 to 3.5 mU /l (in one third of the patients TSH levels even exceeded 1.0 mU/l). Moreover, we found no relevant correlation between TSH and TcTU or V(aut). CONCLUSIONS: In Germany, in at far the largest proportion of patients with autonomous thyroid nodules objectified by means of scintigraphy, TSH levels are within the normal range. Since such nodules with maximum safety can be classified as benign, a corresponding scintigraphic finding has a high priority for the patient. These current data support that it is not reasonable to restrict scintigraphy to patients with subnormal TSH values in this country.
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Biomarcadores de Tumor/sangre , Cintigrafía/estadística & datos numéricos , Nódulo Tiroideo/sangre , Nódulo Tiroideo/diagnóstico por imagen , Tirotropina/sangre , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Alemania/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Reproducibilidad de los Resultados , Medición de Riesgo/métodos , Factores de Riesgo , Sensibilidad y Especificidad , Nódulo Tiroideo/epidemiología , Adulto JovenRESUMEN
AIM: The standardized uptake value (SUV) of 18FDG-PET is an important parameter for therapy monitoring and prognosis of malignant lesions. SUV determination requires delineating the respective volume of interest against surrounding tissue. The present study proposes an automatic image segmentation algorithm for lesion volume and FDG uptake quantitation. METHODS: A region growing-based algorithm was developed, which goes through the following steps: 1. Definition of a starting point by the user. 2. Automatic determination of maximum uptake within the lesion. 3. Calculating a threshold value as percentage of maximum. 4. Automatic 3D lesion segmentation. 5. Quantitation of lesion volume and SUV. The procedure was developed using CTI CAPP and ECAT 7.2 software. Validation was done by phatom studies (Jaszczak phantom, various "lesion" sizes and contrasts) and on studies of NSCLC patients, who underwent clinical CT and FDG-PET scanning. RESULTS: Phantom studies demonstrated a mean error of 3.5% for volume quantification using a threshold of 41% for contrast ratios >or=5 : 1 and sphere volumes >5 ml. Comparison between CT- and PET-based volumetry showed a high correlation of both methods (r = 0.98) for lesions with homogeneous FDG uptake. Radioactivity concentrations were underestimated by on average -41%. Employing an empirical threshold of 50% for SUV determination, the underestimation decreased to on average -34%. CONCLUSIONS: The algorithm facilitates an easy and reproducible SUV quantification and volume assessment of PET lesions in clinical practice. It was validated using NSCLC patient data and should also be applicable to other tumour entities.
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Imagenología Tridimensional/métodos , Neoplasias/diagnóstico por imagen , Tomografía de Emisión de Positrones , Algoritmos , Simulación por Computador , Fluorodesoxiglucosa F18 , Humanos , Procesamiento de Imagen Asistido por Computador , Fantasmas de Imagen , RadiofármacosRESUMEN
UNLABELLED: Aim of this study is the validation of a simple method for evaluating the depth of the target volume within the radioiodine test by analyzing the emitted iodine-131 energy spectrum. PATIENTS, METHODS: In a total of 250 patients (102 with a solitary autonomous nodule, 66 with multifocal autonomy, 29 with disseminated autonomy, 46 with Graves' disease, 6 for reducing goiter volume and 1 with only partly resectable papillary thyroid carcinoma), simultaneous uptake measurements in the Compton scatter (210 +/- 110 keV) and photopeak (364-45/+55 keV) windows were performed over one minute 24 hours after application of the 3 MBq test dose, with subsequent calculation of the respective count ratios. Measurements with a water-filled plastic neck phantom were carried out to perceive the relationship between these quotients and the average source depth and to get a calibration curve for calculating the depth of the target volume in the 250 patients for comparison with the sonographic reference data. Another calibration curve was obtained by evaluating the results of 125 randomly selected patient measurements to calculate the source depth in the other half of the group. RESULTS: The phantom measurements revealed a highly significant correlation (r = 0,99) between the count ratios and the source depth. Using these calibration data, a good relationship (r = 0,81, average deviation 6 mm corresponding to 22%) between the spectrometric and the sonographic depths was obtained. When using the calibration curve resulting from the 125 patient measurements, the overage deviation in the other half of the group was only 3 mm (12%). There was no difference between the disease groups. CONCLUSION: The described method allows on easy to use depth correction of the uptake measurements providing good results.
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Radioisótopos de Yodo , Glándula Tiroides/anatomía & histología , Tiroiditis/diagnóstico por imagen , Carcinoma Papilar/diagnóstico por imagen , Femenino , Enfermedad de Graves/diagnóstico por imagen , Humanos , Masculino , Cintigrafía , Reproducibilidad de los Resultados , Espectrometría por Rayos X , Glándula Tiroides/diagnóstico por imagen , Neoplasias de la Tiroides/diagnóstico por imagenRESUMEN
AIM: To test the feasibility of the Thyroid Imaging Reporting And Data System (TIRADS) according to Horvath and Kwak for the assessment of thyroid nodules. PATIENTS, METHOD: Retrospective analysis of patients with thyroid nodules applying the following inclusion criteria: B-mode-ultrasound, surgery and histological results. Thyroid nodules were classified as TIRADS 2, 3, 4A, 4B, 4C, 5 and 6. RESULTS: A total of 172 patients were included (133 women, 48 ± 13 years, 39 men, 49 ± 11 years) with 222 thyroid nodules (24.9 ± 11.5 mm). Final histological diagnosis revealed 203 benign nodules (91%) and 19 malignant nodules (9%; 18 papillary thyroid carcinoma, PTC, and one medullary thyroid carcinoma, MTC). One hundred and sixty thyroid nodules were hypofunctioning in 99mTc-pertechnetate-scintigraphy, 14 nodules were hyperfunctioning and 46 nodules were classified as indifferent. In two cases with small carcinoma < 1 cm 99mTc-pertechnetate-scintigraphy was not performed. According to Horvath, the prevalence of malignancy was 6.7% in TIRADS 2, 0% in 3, 1.9% in 4A, 33% in 4B, 12.5% in 5 and 100% in 6; 73 nodules (39%) were not clearly classifiable, including 3 carcinoma (4.1%). According to Kwak, the prevalence of malignancy was 6.9% in TIRADS 2, 0% in 3, 2% in 4A, 4.1% in 4B, 23.1% in 4C, and 100% in 5 and 6, respectively. Notably, in the subgroup of hot nodules, 11 (79%) were graded as TIRADS 4A or higher, and thus advisable for fine-needle aspiration biopsy in both TIRADS. CONCLUSION: The TIRADS described by Horvath is not practicable due to numerous unclassifiable nodules. The revised TIRADS published by Kwak is feasible and suitable to assess the prevalence of malignancy, but it cannot replace scintigraphic imaging. Fine-needle-biopsy is not necessary in nodules categorized as (K)TIRADS 3, 4A and 5.
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Interpretación de Imagen Asistida por Computador/métodos , Sistemas de Información Radiológica/estadística & datos numéricos , Neoplasias de la Tiroides/diagnóstico por imagen , Neoplasias de la Tiroides/epidemiología , Nódulo Tiroideo/diagnóstico por imagen , Nódulo Tiroideo/epidemiología , Adulto , Diagnóstico Diferencial , Femenino , Alemania/epidemiología , Humanos , Masculino , Prevalencia , Reproducibilidad de los Resultados , Medición de Riesgo/métodos , Sensibilidad y Especificidad , Neoplasias de la Tiroides/clasificación , Nódulo Tiroideo/clasificación , UltrasonografíaRESUMEN
There is controversy whether simultaneous thyrostatic medication influences the outcome of radioiodine (131I) therapy in Graves' disease by reducing the absorbed energy dose of 131I when delivering a standard dose. We therefore sought to ascertain whether the outcome of ablative 131I therapy is in any way affected by simultaneous thyrostasis (carbimazole) by aiming for a constant absorbed dose of 200-250 Gy. We prospectively studied 207 patients with Graves' disease (106 with and 101 without simultaneous carbimazole at the time of 131I therapy). All patients were reexamined 3, 6, and 12 months after 131I therapy. The 101 nonthyrostatic patients showed a highly significantly greater success rate (93%) than the 106 thyrostatic patients (49%). Stepwise logistic regression demonstrated that failure was related to the administration of carbimazole during 131I therapy (P < 0.00005) and the absorbed dose (P < 0.025), but was not related to free T3, free T4, TSH receptor antibodies, or thyroid volume. The success rate was 100% in 93 nonthyrostatic patients with absorbed doses of 200 Gy or more, but was only 12.5% (1 of 8) for absorbed doses less than 200 Gy. Correlation between success and absorbed dose was significantly higher for nonthyrostatic than for thyrostatic patients (r = 0.93 vs. r = 0.24). Sixteen patients who discontinued thyrostasis 1-3 days before 131I therapy showed 94% successes. Simultaneous thyrostasis is the decisive factor against a successful 131I therapy even if the significantly reduced 131I uptake/half-life values under thyrostasis are compensated with a higher delivered dose to ensure a comparable absorbed dose, possibly due to the additionally effective radioprotective properties of carbimazole. Therefore, if clinically feasible, we recommend discontinuing thyrostasis at least 1 day before beginning 131I therapy, because even in hyperthyroid nonthyrostatic patients the success rate was 100%.
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Antitiroideos/uso terapéutico , Carbimazol/uso terapéutico , Enfermedad de Graves/radioterapia , Radioisótopos de Yodo/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Dosificación RadioterapéuticaRESUMEN
This study was undertaken to determine the effects of thin (60 microns) and thick (240 microns) soft contact lenses of equal water content (70%) and power on nonlesioned and lesioned rabbit corneas. In one group of animals, corneas were not lesioned. Thin lenses were placed on left corneas and thick lenses on right corneas. In a second group, lesions were made in both corneas. Left corneas were covered with thin lenses and right corneas with thick lenses. Post-treatment times were 8 hr and 24 hr. At sacrifice, one-half of the cornea was fixed in 4% buffered glutaraldehyde for SEM study. The other half was cut into segments, fixed in a buffered glutaraldehyde-ruthenium red (RR) solution post-osmicated in osmium containing RR and prepared for TEM. At both 8 hr and 24 hr SEM showed cell migration in lesioned corneas covered with thin lenses but not in lesioned corneas covered with thick lenses. At 8 hr, TEM of nonlesioned and lesioned corneas showed no changes in the thickness of the corneal epithelium or the RR staining of the surface. At 24 hr, in nonlesioned corneas covered with thick lenses, the RR staining of microvilli and the height of the corneal epithelium were less than in nonlesioned corneas covered with thin lenses. In lesioned corneas covered with thick lenses, the thickness of the cornea was markedly reduced, the RR staining of microvilli was less and basal cells were more compressed than in lesioned corneas covered with thin lenses. The results of this study indicate that the thickness of a soft contact lens is important in treating corneal trauma.
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Lentes de Contacto Hidrofílicos , Córnea/fisiología , Cicatrización de Heridas , Animales , Córnea/ultraestructura , Diseño de Equipo , Microscopía Electrónica , Microscopía Electrónica de Rastreo , ConejosRESUMEN
Corneal lesions 7.5 mm. in diameter were made with an ocular trephine in rabbits. The time periods studied were 0, 30 min., and 1, 2, 4, 8, 16, and 24 hr. At the end of the time period, the cornea was flooded with 4% glutaraldehyde, buffered with cacodylate, pH 7.4, and kept moist until removed. It was then fixed for 24 hr. Half of the sample was dehydrated in graded alcohols, critical-point-dried, coated with gold palladium alloy, and viewed in an AMR-1000 scanning electron microscope at an accelerating voltage of 20 kv. From 0 to 4 hr. cell trauma, debris, and retraction are seen at the margin of the lesion. From 8 to 24 hr. a significant number of polymorphonuclear leukocytes are present over the total surface but in especially large numbers at the wound margin. At 16 to 24 hr. evidence of cell movement is present. Cells show ruffling membranes a decreased number of microvilli, and a few filopodia along the advancing edge.
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Córnea/ultraestructura , Animales , Membrana Basal/ultraestructura , Córnea/fisiología , Epitelio/fisiología , Epitelio/ultraestructura , Leucocitos/citología , Microscopía Electrónica de Rastreo , Conejos , Cicatrización de HeridasRESUMEN
Impairment of left ventricular function during controlled myocardial ischemia induced by coronary angioplasty has been reported from angiographic and echocardiographic studies. Ejection fraction, peak ejection, peak filling rates, and end-systolic and end-diastolic volumes were investigated before, during and after coronary occlusion on-line with a nonimaging scintillation probe. The study consisted of 18 patients (mean age 59 +/- 10 years) with coronary artery stenosis of greater than 70%. During balloon inflation of 60 seconds' duration, coronary occlusion pressure was 31.6 +/- 12 mm Hg. There was no significant change in heart rate. Delay between first and second dilatation was 109 +/- 63 seconds. Ejection fraction decreased from 53 +/- 16 to 40 +/- 12% (first dilatation, p less than 0.01) and to 39 +/- 14% (second dilatation, p less than 0.01) and recovered to 51 +/- 16% 5 minutes after the second dilatation. Peak ejection rate was significantly reduced during the first and second balloon inflations. Peak filling rate decreased from 2.5 +/- 0.8 to 2.0 +/- 0.7 end-diastolic volume.s-1 (first dilatation, p less than 0.01) and to 1.8 +/- 0.7 end-diastolic volume.s-1 (second dilatation, p less than 0.01) and remained reduced at 2.2 +/- 0.7 end-diastolic volume.s-1 (p = not significant) at 5 minutes after the second dilatation. End-systolic and end-diastolic volumes increased significantly during the first and second dilatations and returned to normal after dilatation. It is concluded that short, controlled myocardial ischemia during coronary angioplasty leads to a decrease in systolic and diastolic left ventricular function. Sequential dilatations do not further decrease function if a sufficient interval is kept.
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Angioplastia Coronaria con Balón , Enfermedad Coronaria/terapia , Imagen de Acumulación Sanguínea de Compuerta , Función Ventricular Izquierda/fisiología , Gasto Cardíaco/fisiología , Volumen Cardíaco/fisiología , Cesio , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/fisiopatología , Vasos Coronarios/fisiopatología , Diástole/fisiología , Electrocardiografía , Imagen de Acumulación Sanguínea de Compuerta/instrumentación , Imagen de Acumulación Sanguínea de Compuerta/métodos , Humanos , Yoduros , Masculino , Persona de Mediana Edad , Pertecnetato de Sodio Tc 99m , Volumen Sistólico/fisiología , Sístole/fisiología , Factores de TiempoRESUMEN
We investigated the predictive value of sequential FDG PET before and after high-dose chemotherapy (HDT) and autologous stem cell transplantation (ASCT) in 24 patients suffering from non-Hodgkin's lymphoma (NHL). FDG PET was performed at baseline, after three cycles of induction therapy, before and after HDT with ASCT. Response assessment from sequential PET scans using standardized uptake values (SUV) was available in 22 patients at the time of transplantation. Partial metabolic response (PMR) was defined as a >25% decrease of SUV between successive PET scans [corrected]. Six of seven patients who did not achieve a PMR after complete induction therapy developed lymphoma progression, while 10 of 15 patients with complete metabolic response (CMR) or PMR remained in continuous remission. Four of seven patients with less than PMR after induction therapy died vs two of 15 patients with CMR/PMR. Median progression-free and overall survival of patients with less than PMR after HDT and ASCT was 9 and 29 months, respectively. In contrast, neither conventional re-staging nor the International Prognostic Index were predictive. These data suggest that sequential quantitative PET imaging does enlarge the concept of chemosensitivity used to select patients with high-risk NHL for HDT and ASCT or to route them to alternative treatments.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Fluorodesoxiglucosa F18 , Trasplante de Células Madre Hematopoyéticas , Linfoma no Hodgkin/diagnóstico , Linfoma no Hodgkin/terapia , Tomografía Computarizada de Emisión/métodos , Adulto , Anciano , Femenino , Trasplante de Células Madre Hematopoyéticas/métodos , Trasplante de Células Madre Hematopoyéticas/mortalidad , Humanos , Linfoma no Hodgkin/mortalidad , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Inducción de Remisión/métodos , Análisis de Supervivencia , Tasa de Supervivencia , Trasplante AutólogoRESUMEN
The interradicular alveolar bones of the nonhibernating and hibernating ground squirrels were compared using light and transmission electron microscopy. During hibernation changes occurring in the bone suggest osteocytic osteolysis. Minerals may be mobilized from bone for utilization elsewhere in the body to maintain a minimal metabolic level for survival.
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Proceso Alveolar/ultraestructura , Hibernación , Animales , Mandíbula/ultraestructura , Organoides/ultraestructura , Osteocitos/ultraestructura , Osteólisis/patología , SciuridaeRESUMEN
We sought to ascertain how high the success rates of radioiodine therapy are for Graves' disease patients with large diffuse goiters when aiming for a constant absorbed dose of 250 Gy. Thirty-six patients with a thyroid volume of 50-110 mL were evaluated for changes in thyroid function and appearance 3, 6, and 12 months after radioiodine therapy. Success was defined as definitive elimination of hyperthyroidism following therapy (hypothyroidism corrected with thyroxine on diagnosis); failure as persistent/recurrent hyperthyroidism after 12 months. Overall success rate was 50%. However, a subgroup of 20 patients without simultaneous carbimazole (carbimazole-off) showed a highly significantly larger success rate (85%) than the 16 patients with simultaneous carbimazole (carbimazole-on) at the time of radioiodine therapy (6.3%, p < 0.000005). Successful cases showed a significantly higher volume reduction after radioiodine than failures (75.5% vs. 35.4%, p < 0.00005). Stepwise logistic regression showed that therapy failure was related to administration of carbimazole during radioiodine therapy (p < 0.0250 and absorbed dose (p < 0.05), but not thyroid function (free triiodothyronine [FT3] and free thyroxine [FT4]), initial thyroid volume or thyrotropin-receptor antibody (TRAb) value. However, a significant correlation of therapy success to absorbed dose (r = 0.69, p < 0.005) could be shown only for carbimazole-off patients, but not for the others. Finally, multivariate factor analysis consistently showed that therapy success was correlated only to absorbed dose and antithyroid drugs, not to initial thyroid volume, TRAb value, or thyroid function. Thyroid volume per se is not responsible for the lower success rate in Graves' disease patients with large goiters because even a comparable group of 32 Graves' disease patients with small thyroid glands (< or =20 mL) and without simultaneous carbimazole showed a success rate of 87.5%. The high failure rate in the carbimazole-on patients (absorbed dose comparable to carbimazole-off) is due to the simultaneous administration of carbimazole. Therefore, if clinically feasible, we recommend discontinuing carbimazole at least one day before beginning radioiodine therapy.
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Antitiroideos/uso terapéutico , Carbimazol/uso terapéutico , Bocio/patología , Enfermedad de Graves/tratamiento farmacológico , Enfermedad de Graves/radioterapia , Radioisótopos de Yodo/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Carbimazol/administración & dosificación , Esquema de Medicación , Femenino , Enfermedad de Graves/fisiopatología , Humanos , Radioisótopos de Yodo/administración & dosificación , Masculino , Persona de Mediana Edad , Análisis Multivariante , Glándula Tiroides/fisiopatología , Resultado del TratamientoRESUMEN
Since the majority of patients with ovarian cancer present with advanced stages of the disease and chemotherapy is an integral part of the treatment at this stage, the role of the nurse is paramount. Nursing management of patients receiving chemotherapy focuses primarily on education. Patients and families need to learn about the drugs to be administered, their schedules, and potential side effects. The author discusses the management of side effects resulting from the two-drug cisplatin-cyclophosphamide combination and their respective analogs. Care of patients participating in clinical trials, especially those involving intraperitoneal therapy, also is discussed.
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Antineoplásicos/efectos adversos , Neoplasias Ováricas/enfermería , Antineoplásicos/uso terapéutico , Femenino , Humanos , Riñón/efectos de los fármacos , Leucopenia/inducido químicamente , Leucopenia/enfermería , Neoplasias Ováricas/tratamiento farmacológico , Vejiga Urinaria/efectos de los fármacos , Vómitos/inducido químicamente , Vómitos/enfermeríaRESUMEN
The histology of the anterior cruciate ligament was studied by a modified technique of the Gairns gold chloride stain for neural elements. Three morphological types of mechanoreceptors and free nerve-endings were identified: two of the slow-adapting Ruffini type and the third, a rapidly adapting Pacinian corpuscle. Rapidly adapting receptors signal motion and slow-adapting receptors subserve speed and acceleration. Free nerve-endings, which are responsible for pain, were also identified within the ligament. These neural elements comprise 1 per cent of the area of the anterior cruciate ligament.
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Articulación de la Rodilla , Ligamentos Articulares/inervación , Nervios Periféricos/anatomía & histología , Axones/anatomía & histología , Humanos , Procesamiento de Imagen Asistido por Computador , Mecanorreceptores/anatomía & histología , Terminaciones Nerviosas/anatomía & histología , Corpúsculos de Pacini/anatomía & histologíaRESUMEN
Palatal myoclonus with its concomittant objective tinnitus is often a missed diagnosis and poses a problem to the clinician in separating it from other middle ear anomalies. The etiology and symptomatology is outlined, but as suggested by our case presentations are not always diagnostic. The anatomical pathways of palatal myoclonus are traced, and its etiological complexities are realized when any locus or pathology along these tracks may create the characteristic chronic rhythmic contractions. We have experienced excellent results in determining a differential diagnosis of palatal myoclonus from other middle ear problems by the correlations of impedance audiometry with our clinical findings. Although the etiology is not defined the target structures can be separated from this test method and, therefore, enable more specific therapy.
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Mioclonía/diagnóstico , Hueso Paladar , Acúfeno/diagnóstico , Adolescente , Adulto , Anciano , Audiometría , Diagnóstico Diferencial , Enfermedades del Oído/diagnóstico , Oído Medio , Femenino , Humanos , MasculinoRESUMEN
We evaluated the clinical significance of 18F-FDG PET to detect malignant ovarian neoplasms and tumor spread. 40 patients (median age: 57.5 years) underwent laparotomy because of clinical suspicion of malignant ovarian tumors or recurrent disease. The results of the preoperatively performed PET were correlated with the postoperative histologic diagnosis and the intraoperatively assessed tumor spread. In 10 of 40 patients benign tumors were found, among which a tubo-ovarian abscess was the only one diagnosed as false positive. 4/30 malignant neoplasms did not originate from the coelomic epithelium, but all were correctly recognized as malignant tumors by PET, as was recurrent ovarian cancer in 12 patients. Out of 14 primary ovarian carcinomas, 2 borderline tumors and 1 well-differentiated adenocarcinoma FIGO stage I were not correctly identified. Considering the tumor type, sensitivity, and specificity were 90%, calculating for the positive and negative predictive value 96% and 75%, respectively, and 90% for the diagnostic accuracy. Those statistical parameters were slightly lower for PET detection of lymph node metastasis and peritoneal carcinomatosis. Although its diagnostic accuracy may vary depending on the clinical application, 18F-FDG PET is basically a suitable method for detecting ovarian malignancies, particularly in patients with relapsed ovarian carcinoma.
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1. Gingiva from the buccal surfaces of the mandibular first molars was grafted to the alveolar mucosa of each of the three premolars in six adult Beagle dogs. Biopsies were made at 0,2,3,4,5,6,7,8,10,14,21 days and at 1 and 6 months. 2. The specimens were fixed in 2% glutaraldehyde, buffered with cacodylate, pH 7.4, rinsed in buffer, dehydrated in graded alcohols, critical point dried, coated with gold palladium alloy and viewed in an AMR-1000 SEM at a tilt of 20 to 25 degrees and an accelerating voltage of 20 kv. 3. The results of this study parallel those reported on the basis of light microscopic studies. The three-dimensional visualization of the graft shows that the external layer of epithelium degenerates and desquamates, except for the basal layer and the structural architecture of the connective tissue is not as well organized. 4. By 21 days the graft is essentially healed, both clinically and histologically.
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Encía/fisiología , Encía/ultraestructura , Animales , Tejido Conectivo/fisiología , Tejido Conectivo/ultraestructura , Perros , Epitelio/fisiología , Epitelio/ultraestructura , Femenino , Encía/trasplante , Microscopía Electrónica de Rastreo , Trasplante Autólogo , Cicatrización de HeridasRESUMEN
This study attempted to characterize neural elements within the human cervical intervertebral disc. Cervical intervertebral discs were obtained from four adult human subjects at autopsy. Discs were stained in bulk with gold chloride, sectioned, and viewed with the light microscope. Nerve fibers appeared to enter the disc in the posterolateral direction and course both parallel and perpendicular to the bundles of the anulus fibrosus. Nerves were seen throughout the anulus but were most numerous in the middle third of the disc. Receptors resembling Pacinian corpuscles and Golgi tendon organs were seen in the posterolateral region of the upper third of the disc. These results provide further evidence that human cervical intervertebral discs are supplied with both nerve fibers and mechanoreceptors.
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Vértebras Cervicales/anatomía & histología , Compuestos de Oro , Disco Intervertebral/inervación , Mecanorreceptores/citología , Fibras Nerviosas/química , Adulto , Oro , Corpúsculos de Golgi-Mazzoni , Humanos , Coloración y EtiquetadoRESUMEN
Transluminal coronary angioplasty (PTCA) causes transient occlusion of the coronary artery and temporary ischemia of the left ventricle. Left ventricular dysfunction during silent and symptomatic episodes of myocardial ischemia during PTCA was evaluated continuously with a newly developed miniature, non-imaging scintillation probe. Parameters of left ventricular function were compared before and during balloon inflations of 60 s duration: ejection fraction (EF), indices of end-systolic and end-diastolic volumes (ESV, EDV), peak ejection and peak filling rates (PER, PFR). 13 patients (age 54 +/- 7.4 years) were symptomatic, 10 patients (age 61 +/- 8 years) were asymptomatic. Impairment of left ventricular function during ischemia did not show any significant differences between the symptomatic and asymptomatic patients. It is therefore concluded that symptomatic and asymptomatic episodes of myocardial ischemia during PTCA cause similar impairment of systolic and diastolic left ventricular function. The degree of left ventricular dysfunction during PTCA cannot be estimated on the basis of clinical symptoms.
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Angioplastia Coronaria con Balón , Isquemia Miocárdica/fisiopatología , Función Ventricular Izquierda/fisiología , Anciano , Humanos , Masculino , Persona de Mediana EdadRESUMEN
AIM: Of the present study was to investigate the feasibility of 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG) imaging in oncological patients with a dual head gamma camera modified for coincidence detection (MCD). METHODS: Phantom studies were done to determine lesion detection at various lesion-to-background ratios, system sensitivity and spatial resolution. Thirty-two patients with suspected or known malignant disease were first studied with a dedicated full-ring PET system (DPET) applying measured attenuation correction and subsequently with an MCD system without attenuation correction. MCD images were first interpreted without knowledge of the DPET findings. In a second reading, MCD and DPET were evaluated simultaneously. RESULTS: The phantom studies revealed a comparable spatial resolution for DPET and MCD (5.9 x 6.3 x 4.2 mm vs. 5.9 x 6.5 x 6.0 mm). System sensitivity of MCD was less compared to DPET (91 cps/Bq/ml/cmFOV vs. 231 cps/Bq/ml/cmFOV). At a lesion-to-background ratio of 4:1, DPET depicted a minimal phantom lesion of 1.0 cm in diameter, MCD a minimal lesion of 1.6 cm. With DPET, a total of 91 lesions in 27 patients were classified as malignant. MCD without knowledge of DPET results revealed increased FDG uptake in all patients with positive DPET findings. MCD detected 72 out of 91 DPET lesions (79.1%). With knowledge of the DPET findings, 11 additional lesions were detected (+12%). MCD missed lesions in six patients with relevance for staging in two patients. All lesions with a diameter above 18 mm were detected. CONCLUSION: MCD FDG imaging yielded results comparable to dedicated PET in most patients. However, a considerable number of small lesions clearly detectable with DPET were not detected by MCD alone. Therefore, MCD cannot yet replace dedicated PET in all oncological FDG studies. Further technical refinement of this new method is needed to improve image quality (e.g. attenuation correction).
Asunto(s)
Fluorodesoxiglucosa F18 , Cámaras gamma , Neoplasias/diagnóstico por imagen , Radiofármacos , Tomografía Computarizada de Emisión , Adulto , Anciano , Femenino , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Linfoma/diagnóstico por imagen , Persona de Mediana Edad , Fantasmas de Imagen , Recurrencia , Sensibilidad y EspecificidadRESUMEN
AIM: Evaluation of potential synergistic effects of combined image interpretation of FDG PET using a gamma camera modified for coincidence detection (hybrid PET) and computed tomography (CT) and comparison of the diagnostic accuracy of hybrid PET and dedicated PET in patients with head and neck cancer. METHODS: Forty-two patients with suspected primary or recurrent cancer were included. Twenty-four patients underwent dedicated PET in addition to attenuation-corrected hybrid PET using a one-day protocol. RESULTS: Sensitivity, specificity and accuracy for detection of primary or recurrent head and neck cancer were 74, 73, and 74% for hybrid PET, 52, 82, and 60% for CT and 77, 82, and 79% for combined reading. With the combination of CT and hybrid PET all cases of recurrent disease were detected. The largest tumour not detected was 1.7 cm in diameter. Sensitivity, specificity and accuracy for the detection of neck sides with lymph node metastases were 69, 88, and 85% for hybrid PET, 62, 88, and 84% for CT, 69, 99, and 94% for combined image interpretation. With combined interpretation four involved neck sides were missed including two cases of microscopic metastases. Hybrid PET revealed concordant results to dedicated PET in all patients with respect to the detection of primary or recurrent tumour and in 45 of 48 neck sides (94%) with the same number of false negative findings. CONCLUSION: The combination of functional information of hybrid PET and morphological information of CT by the simple approach of combined image interpretation improves the sensitivity for the detection of primary/recurrent head and neck cancer and increases the specificity of lymph node staging compared to CT alone. The accuracy of hybrid PET and dedicated PET was almost identical.