RESUMEN
This study aimed to develop a new experimental model of partial ureteric obstruction in sheep. Graded obstruction of the ureter using various sized catheters (Fr 3-8) for variable durations up to 6 weeks was performed in 19 sheep. The kidneys were studied by radionuclide diuretic renography for up to 21 weeks and had histopathological examination at the end of the experiment. Catheters of Fr 3 or Fr 5 should be used to block the ureter for a minimum of three weeks to produce sufficient functional and pathological changes to be studied. The advantages and disadvantages of this model are discussed.
Asunto(s)
Modelos Animales de Enfermedad , Riñón/patología , Obstrucción Ureteral/patología , Animales , Femenino , Riñón/diagnóstico por imagen , Riñón/fisiopatología , Masculino , Renografía por Radioisótopo , Radiofármacos , Ovinos , Pentetato de Tecnecio Tc 99m , Obstrucción Ureteral/diagnóstico por imagen , Obstrucción Ureteral/fisiopatologíaRESUMEN
Selection of patients with chronic bilharzial uropathy (CBU) for surgery is a difficult problem due to the presence of grossly dilated urinary tracts without a significant obstruction in most of the cases. In this prospective study of 40 patients with CBU, the time-activity curve (TAC) patterns of the pre- and postoperative Tc-99m DTPA diuretic renography (RDR) studies were compared with the corresponding parenchymal transit time indices (PTTI). The aims were to find out which of these renographic parameters was more accurate in identifying obstruction and which was better in predicting the outcome of surgery. PTTI was more sensitive than TAC in identifying obstruction (96% and 92%, respectively) but it was less specific (78% and 98%). The detection accuracy of RDR for obstruction using TAC patterns was 96% compared to 84% using PTTI. Being independent of renal uptake function, PTTI could not predict the outcome of surgery as TAC could. In contrast to PTTI, TAC patterns could differentiate obstructed kidneys from severely nephropathic kidneys. However, PTTI was useful in identifying kidneys with residual nephropathy.
Asunto(s)
Renografía por Radioisótopo , Esquistosomiasis Urinaria/diagnóstico por imagen , Pentetato de Tecnecio Tc 99m , Obstrucción Ureteral/diagnóstico por imagen , Obstrucción Ureteral/cirugía , Adulto , Enfermedad Crónica , Predicción/métodos , Furosemida , Humanos , Persona de Mediana Edad , Periodo Posoperatorio , Estudios Prospectivos , Renografía por Radioisótopo/métodos , Sensibilidad y Especificidad , Factores de Tiempo , Resultado del Tratamiento , Obstrucción Ureteral/parasitologíaRESUMEN
The selection of patients with chronic obstructive uropathy for surgery is difficult because of problems in identifying true obstruction in a grossly dilated urinary tract. This is especially so in schistosomal (bilharzial) obstructive uropathy. A prospective study of 90 patients (68 with chronic schistosomal and 22 with non-bilharzial obstructive uropathy) was carried out. All patients underwent pre-operative and post-operative radionuclide 99mTc DTPA diuretic renography (RDR). The aims were to assess the value of RDR in the pre- and post-operative management of these patients and whether it could predict the outcome of surgery. Distinctive renogram patterns were identified in patients who required surgical management. These were found useful in monitoring the results and in predicting the outcome of surgery.
Asunto(s)
Compuestos de Organotecnecio , Ácido Pentético , Cuidados Preoperatorios , Renografía por Radioisótopo , Esquistosomiasis Urinaria/complicaciones , Obstrucción Ureteral/diagnóstico por imagen , Humanos , Periodo Posoperatorio , Valor Predictivo de las Pruebas , Estudios Prospectivos , Pentetato de Tecnecio Tc 99m , Obstrucción Ureteral/etiología , Obstrucción Ureteral/cirugíaRESUMEN
There is no simple analytical test. Radionuclide diuretic renography (RDR), being a dynamic imaging study reflecting the function of the kidney and the urodynamics of the urinary tracts, has the potential to predict the outcome of surgery in obstructive uropathy. In 12 sheep, we occluded one ureter for a maximum of seven weeks and followed up for a maxim of five weeks after release of occlusion. Repeated Tc-99m DTPA diuretic renography studies were performed and the results were correlated with the duration of complete ureteric occlusion. The renal uptake percentage and the extraction slope of the time activity curve (TAC) showed progressive and steady decrease over the period of the occlusion. By the fifth week there was very low uptake (less than 18%) and the TAC was almost flat, suggestive of severe nephropathy. The parenchymal transit time index (PTTI) showed immediate rise after occlusion but with no progressive increase in its value. By the fifth week it dropped down to normal. After release, the recovery of function showed good correlation with the renal uptake percentage and extraction slope of TAC before release of occlusion. Therefore both these parameters, rather than PTTI, can be used to predict the outcome of surgery before the release of complete obstruction of the ureter.
Asunto(s)
Renografía por Radioisótopo , Pentetato de Tecnecio Tc 99m , Obstrucción Ureteral/diagnóstico por imagen , Animales , Furosemida/administración & dosificación , Riñón/fisiopatología , Ovinos , Factores de Tiempo , Obstrucción Ureteral/fisiopatologíaRESUMEN
Twenty-two patients with brucella spondylitis and neurobrucellosis were studied during a 2-year period. The diagnosis was based on history of exposure, compatible signs and symptoms, high antibody titre and/or positive culture of a clinical specimen(s). Spondylitis was confirmed by plain radiographs, bone scan, CT and in some cases by histology. Neurobrucellosis was confirmed by CSF examination and culture, myelography, NCV, EMG and CT head. The spondylitis was early in 4 cases, chronic active in 12, smouldering "partially healed" in 3 and healed in 3 cases. Of these, 15 patients (68%) had neurological complications of various types. Plain radiographs were not a good index of activity of spondylitis. Tc99 bone scan was not specific and it remained positive long after the completion of therapy. CT was superior in revealing details of bone destruction, soft tissue swelling and entrapment of nerve roots and cord. The 3 modalities were complementary. Spondylitis is commonly associated with neurobrucellosis and symptoms of one may over shadow those of the other and in some cases neurobrucellosis may be subclinical. In all cases of spondylitis, a thorough search for neurobrucellosis should be made and vice versa. Prolonged treatment with a combination of 3 anti-brucella drugs is recommended and prolonged follow-up is necessary.
Asunto(s)
Brucelosis/complicaciones , Vértebras Lumbares/diagnóstico por imagen , Enfermedades del Sistema Nervioso/microbiología , Espondilitis/microbiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Brucelosis/tratamiento farmacológico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades del Sistema Nervioso/fisiopatología , Espondilitis/complicaciones , Espondilitis/diagnóstico por imagen , Estreptomicina/uso terapéutico , Tomografía Computarizada por Rayos XRESUMEN
Complete ureteric occlusion produces various pathophysiological changes that can be monitored externally by technetium 99m diethylenetriamine penta-acetic acid (99mTc-DTPA) diuretic renography (RDR). Being a dynamic imaging study, it reflects the function of the kidneys and the urodynamics of the urinary tract. The aim of this study was to correlate the changes in parameters of RDR with the histological changes before and after the release of complete ureteric occlusion. In 9 sheep, RDR studies were performed serially after various periods of complete ureteric occlusion (up to 7 weeks) and after release of the occlusion (up to 5 weeks). The histological changes were correlated with changes in RDR. The progressive decrease in renal flow seen on renal images and flow time-activity curves (TACs) was explained by the development of endarteritis and thrombosis of small renal arteries. The progressive decrease in the renal uptake as indicated by the percentage renal uptake and the extraction slope of TAC is related to the progressive damage to the renal parenchyma, initially affecting the collecting ducts and tubules, with increasing interstitial fibrosis in the later stages. Obstruction for 3 weeks or less was associated with moderate damage to the parenchyma from which recovery was possible. Obstruction for 7 weeks was associated with marked damage without chance of recovery. The RDR is a non-invasive technique that can be used to monitor kidney damage after various periods of complete ureteric occlusion and to predict the outcome of surgery before the release of occlusion.
Asunto(s)
Riñón/patología , Renografía por Radioisótopo , Pentetato de Tecnecio Tc 99m , Obstrucción Ureteral/diagnóstico por imagen , Animales , Riñón/fisiopatología , Ovinos , Obstrucción Ureteral/fisiopatologíaRESUMEN
The advantage of Tc-99m HM-PAO, a newly introduced compound for brain perfusion imaging, is illustrated in three patients with suspicion of brain death. With Tc-99m HM-PAO, the carotid flow study is not essential, as it is in the Tc-99m pertechnetate carotid angiogram; planar images are equally useful; and there is no need for SPECT images. For the diagnosis of brain death, Tc-99m HM-PAO can be injected in the intensive care unit and planar images can be obtained at a later time using a mobile camera or whenever the patient can be moved to the nuclear medicine department.
Asunto(s)
Muerte Encefálica/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Compuestos de Organotecnecio , Oximas , Adolescente , Adulto , Arteria Carótida Interna/diagnóstico por imagen , Circulación Cerebrovascular , Humanos , Masculino , Cintigrafía , Exametazima de Tecnecio Tc 99mRESUMEN
A case of false positive I-131 MIBG imaging for detection of pheochromocytoma is presented. There was an area of increased tracer uptake in the left renal region that showed steadily reducing activity over a period of three days. This raised the suspicion of a dilated renal pelvis, which was later confirmed by Tc-99m DTPA imaging. It is advisable in cases of ambiguous I-131 MIBG imaging to use Tc-99m DTPA rather than Tc-99m DMSA for localizing the kidneys and renal pelvis.
Asunto(s)
Radioisótopos de Yodo , Yodobencenos , Enfermedades Renales/diagnóstico por imagen , Pelvis Renal/diagnóstico por imagen , Feocromocitoma/diagnóstico por imagen , 3-Yodobencilguanidina , Adulto , Diagnóstico Diferencial , Reacciones Falso Positivas , Humanos , Masculino , Compuestos Organometálicos , Ácido Pentético , Cintigrafía , Succímero , Ácido Dimercaptosuccínico de Tecnecio Tc 99m , Pentetato de Tecnecio Tc 99mRESUMEN
An 18-year-old male was evaluated for recurrent attacks of right abdominal pain and intermittent jaundice caused by hydatid cysts of the liver. The case illustrates the value of dynamic functional information provided by Tc-99m-HIDA imaging over noninvasive modalities that demonstrate structural changes, such as ultrasound, computed tomography, and tin colloid liver imaging.
Asunto(s)
Colestasis Intrahepática/etiología , Equinococosis Hepática/complicaciones , Compuestos de Tecnecio , Compuestos de Estaño , Adolescente , Colangiopancreatografia Retrógrada Endoscópica , Colestasis Intrahepática/diagnóstico , Equinococosis Hepática/diagnóstico , Humanos , Iminoácidos , Masculino , Compuestos Organometálicos , Tecnecio , Lidofenina de Tecnecio Tc 99m , Estaño , Tomografía Computarizada por Rayos X , UltrasonografíaRESUMEN
To assess the left ventricular function of patients who suffer from post-infarction angina and left ventricular failure in the coronary care unit, 79 consecutive survivors (mean age 48 years) of a first acute myocardial infarction were prospectively studied and followed-up for a mean 18- (10-34) month period. Forty-seven had an uncomplicated infarction, 17 suffered from post-infarction angina and 15 had left ventricular failure. The left ventricular function of these patients prior to discharge from hospital was assessed by cross-sectional echocardiography and radionuclide angiography. Analysis of left ventricular wall motion was performed in all patients using a 11-segment model of the left ventricular. The ejection fraction was determined by echocardiography in 47 patients and by radionuclide angiography in 50. The mean echocardiographic wall motion score of post-infarction angina patients (4.8 +/- 0.8) (+/- SEM) was lower than that of patients with left ventricular failure (9.5 +/- 0.5) (P less than 0.001), but was not different from patients suffering uncomplicated infarctions (4.6 +/- 0.3). The mean echocardiographic ejection fraction was also similar in post-infarction angina (45.3 +/- 4.0; n = 16) and patients with uncomplicated infarction (51.9 +/- 2.7; n = 17), but was lowest in the group of patients with left ventricular failure (35.1 +/- 3.3; n = 14). Similarly, the radionuclide ejection fraction of patients with post-infarction angina (41.4 +/- 3.4; n = 17) and patients with uncomplicated infarction (45.6 +/- 2.7; n = 19) did not differ, but was lower in patients with left ventricular failure (25.9 +/- 2.8; n = 14). The echocardiographic ejection fraction correlated with that obtained by radionuclide angiography in all 46 patients (r = 0.71, P less than 0.001). The wall motion score correlated with the radionuclide ejection fraction in all 50 patients (r = -0.73, P less than 0.001) and with the echocardiographic ejection fraction in 47 patients (r = -0.55, P less than 0.001). During follow-up, 3 (18%) patients suffering post-infarction angina and 2 (13%) with left ventricular failure died. New infarction was seen in 2 (12%) and 1 (7%) patients in these groups, respectively. We conclude that the left ventricular function of patients who suffer from post-infarction angina in the coronary care unit is good, but is impaired in those with even transient left ventricular failure. Echocardiographic assessment of cardiac function prior to hospital discharge was highly successful and may be performed in all such patients.
Asunto(s)
Ecocardiografía/métodos , Infarto del Miocardio/fisiopatología , Adulto , Anciano , Angina de Pecho/etiología , Angina de Pecho/fisiopatología , Femenino , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/fisiopatología , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/patología , Ventrículos Cardíacos/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/complicaciones , Alta del Paciente , Pronóstico , Estudios Prospectivos , Angiografía por Radionúclidos , Volumen SistólicoRESUMEN
Brucellosis is an endemic disease in the Middle East. Its incidence in Kuwait has increased during the last 5 years. Bone and joint involvement causes major symptoms and disabilities. Radionuclide bone scans are more sensitive than radiographs in detecting these lesions. The aim of this study is to describe the abnormal patterns detected on bone imaging in acute and chronic brucellosis. Tc-99m MDP bone scans of 56 patients with established diagnosis of brucellosis (19 acute and 37 chronic) were retrospectively analyzed. Bone scans were positive in 8 of 19 patients (42%) with acute brucellosis and in 28 of 37 patients (76%) with chronic brucellosis. Six patterns were observed: involvement of an entire body of one or more vertebrae, especially at the lumbar region (50%); sacroiliitis (41%); focal high uptake at the junction of the upper and lateral margins of the vertebra "Caries sign" (27%); multiple costovertebral joints and costochondral junction involvement (19%); involvement of large joints similar to degenerative osteoarthritis (25%); and focal involvement of long bone (11%).
Asunto(s)
Brucelosis/diagnóstico por imagen , Enfermedad Aguda , Adulto , Dolor de Espalda/diagnóstico por imagen , Enfermedades Óseas/diagnóstico por imagen , Enfermedad Crónica , Femenino , Humanos , Artropatías/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Cintigrafía , Medronato de Tecnecio Tc 99mRESUMEN
The aim of this study was to describe the abnormal morphological and functional patterns observed in radionuclide diuretic renograms (RDR) in patients with chronic urinary schistosomiasis. A retrospective analysis of RDR for 92 patients was made. It revealed the following abnormalities: A) Morphological changes observed in the images: Pelvicalyceal retention of tracer (and dilatation) was seen in 68% of kidneys. Calyceal retention alone was seen in 5% and pelvic retention alone in 9%. An atrophic kidney was noted in 5%, nephropathic pattern in 3% and normal kidneys in 10%. Ureteric retention of tracer was seen in 64% of ureters. This was frequently associated with pelvicalyceal retention (61%) and this abnormality was bilateral in 44% of the urinary systems. B) Functional changes observed in the time activity curves: Non-obstructive delayed excretion was noted in 71% of kidneys. An obstructed kidney pattern nonresponsive to lasix was seen in 12%, plateau curve due to nephropathic kidney in 3% and atrophic kidney pattern in 4% of kidneys.
Asunto(s)
Esquistosomiasis Urinaria/diagnóstico por imagen , Adulto , Humanos , Masculino , Persona de Mediana Edad , Compuestos Organometálicos , Ácido Pentético , Cintigrafía , Esquistosomiasis Urinaria/patología , Esquistosomiasis Urinaria/fisiopatología , Esquistosomiasis Urinaria/terapia , Pentetato de Tecnecio Tc 99m , Uréter/patología , Obstrucción Ureteral/diagnóstico por imagen , Obstrucción Ureteral/terapiaRESUMEN
Technetium-99m hexamethylpropyleneamine oxime (Tc-99m HM-PAO) was successfully used with single photon emission computed tomography (SPECT) on fourteen comatose patients who had acute head injuries. The SPECT scans were correlated with computed tomography (CT) scans obtained within 24 hours of the injury. Tc-99m HM-PAO SPECT was shown to have the following advantages: It reflected perfusion changes, was more sensitive than CT in demonstrating more lesions, and demonstrated lesions at an earlier stage than those demonstrated with CT. Different types of lesions, as evidenced by cerebral perfusion changes, have been described and categorized. The lesions that had a favorable prognosis could be separated from those with an unfavorable prognosis on the basis of the findings of Tc-99m HM-PAO SPECT.
Asunto(s)
Circulación Cerebrovascular , Traumatismos Craneocerebrales/diagnóstico , Compuestos Organometálicos , Oximas , Tecnecio , Tomografía Computarizada de Emisión/métodos , Tomografía Computarizada por Rayos X , Accidentes por Caídas , Accidentes de Tránsito , Enfermedad Aguda , Adolescente , Adulto , Encéfalo/diagnóstico por imagen , Coma/diagnóstico , Coma/fisiopatología , Traumatismos Craneocerebrales/fisiopatología , Humanos , Masculino , Pronóstico , Exametazima de Tecnecio Tc 99m , Tomografía Computarizada de Emisión/instrumentaciónRESUMEN
A case of hematobilia causing upper gastrointestinal bleeding is demonstrated by Tc-99m DTPA. The advantages of Tc-99m DTPA over Tc-99m sulfur colloid and RBCs are discussed.
Asunto(s)
Adenocarcinoma/cirugía , Hemorragia Gastrointestinal/diagnóstico por imagen , Hemobilia/diagnóstico por imagen , Neoplasias Pancreáticas/cirugía , Complicaciones Posoperatorias/diagnóstico por imagen , Adulto , Coledocostomía , Humanos , Masculino , Compuestos Organometálicos , Ácido Pentético , Cintigrafía , Tecnecio , Pentetato de Tecnecio Tc 99mAsunto(s)
Quemaduras por Electricidad/diagnóstico por imagen , Difosfatos , Corazón/diagnóstico por imagen , Tecnecio , Tomografía Computarizada de Emisión , Adulto , Diagnóstico Diferencial , Reacciones Falso Positivas , Humanos , Masculino , Infarto del Miocardio/diagnóstico por imagen , Pirofosfato de Tecnecio Tc 99mRESUMEN
Phase imaging abnormalities of the right side of the heart detected on multiple gated blood pool angiography (MUGA) have received less attention than similar abnormalities of the left ventricle. It has been found that certain different patterns of phase abnormalities of both right ventricle and right atrium are useful in the detection of six pathological conditions: right bundle branch block, ischemic right coronary artery disease, pericardial effusion, tricuspid regurgitation, pulmonary hypertension, and atrial septal defect. The authors emphasize the importance of these abnormal phase patterns during interpretation of gated cardiac studies, as they are helpful in directing the physicians attention towards the proper diagnosis.
Asunto(s)
Cardiopatías/diagnóstico por imagen , Corazón/diagnóstico por imagen , Adulto , Enfermedad Coronaria/diagnóstico por imagen , Femenino , Bloqueo Cardíaco/diagnóstico por imagen , Defectos del Tabique Interatrial/diagnóstico por imagen , Humanos , Hipertensión Pulmonar/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Derrame Pericárdico/diagnóstico por imagen , Cintigrafía , Insuficiencia de la Válvula Tricúspide/diagnóstico por imagenRESUMEN
Pulmonary hypertension (PH) produces strain followed by hypertrophy and later dilatation of the right ventricle (RV) and pulmonary artery. The signs and symptoms are nonspecific. There is a need for a noninvasive sensitive way to diagnose PH. The purpose of this study is to evaluate phase abnormalities in radionuclide MUGA studies of patients with referred diagnosis of PH. In a retrospective analysis of 44 patients who had a radionuclide multigated study (MUGA) and contrast ventriculography (CV), 19 had high mean pulmonary pressure (over 20 mmHg) and a high pulmonary vascular resistance index (over 2.0). In 15 patients, a delayed phase segment in the RV corresponding to the pulmonary infundibulum and pulmonary conus was noted "The Pulmonary Tongue" sign (PT), 12 had PH (True positive) and 3 did not (false positive) on CV. No PT was seen in the remaining 29 patients, only 7 of them had PH (False negative). The sensitivity, specificity and accuracy of the PT sign in detecting PH was 80%, 72% and 77% respectively. The number of patients was too small to calculate the correlation of the grade of PT with the severity of PH. We conclude that "The Pulmonary Tongue" sign on a MUGA study is clinically useful in detecting PH.
Asunto(s)
Corazón/diagnóstico por imagen , Hipertensión Pulmonar/diagnóstico por imagen , Adulto , Anciano , Femenino , Corazón/fisiopatología , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Hipertensión Pulmonar/patología , Hipertensión Pulmonar/fisiopatología , Masculino , Persona de Mediana Edad , CintigrafíaRESUMEN
We describe a case complicated by infection of a xenograft conduit with subsequent septic emboli to the left kidney in the setting of pulmonary atresia with ventricular septal defect which was positively imaged using radioactive gallium-67. Confirmation was provided by cross-sectional echocardiography and positive blood culture. The patient improved with antibiotic therapy.
Asunto(s)
Bioprótesis/efectos adversos , Prótesis Vascular/efectos adversos , Defectos del Tabique Interventricular/cirugía , Infección de la Herida Quirúrgica/diagnóstico por imagen , Adolescente , Radioisótopos de Galio , Glomerulonefritis/diagnóstico por imagen , Glomerulonefritis/etiología , Humanos , Masculino , Cintigrafía , Infección de la Herida Quirúrgica/etiologíaRESUMEN
Radioactive gallium-67 has been used in a 64-year-old woman who developed persistent fever and a small sinus in the upper chest 6 weeks following open heart surgery for the replacement of a rheumatic aortic valve. The scintigraphy revealed unexpected extensive inflammation tracking down from the region of the sinus to the lower chest in front and under the heart. Chest X-ray and echocardiographic findings were inconclusive. The value of gallium scintigraphy in this case was not only in the localisation of the lesion but also in defining the extent of inflammation, the latter feature determining the need for reintervention.
Asunto(s)
Procedimientos Quirúrgicos Cardíacos/efectos adversos , Radioisótopos de Galio , Corazón/diagnóstico por imagen , Infección de la Herida Quirúrgica/diagnóstico por imagen , Femenino , Humanos , Persona de Mediana Edad , CintigrafíaRESUMEN
Retrospective analyses of the stress thallium studies of 51 patients with a history of previous infarctions or definite stable angina were performed in order to determine the extent of the coronary-artery disease (CAD). The results were correlated with recent coronary-angiography findings in order to assess the effect of including right-ventricule (RV) visualization on the accuracy of the detection of right coronary-artery (RCA) disease, as well as the effect of graded stenosis or occlusion of the RCA and the presence of disease of the other coronary vessels on the visualization of the RV. Eight patients had normal coronary arteries. The other 43 patients had CAD, only 5 of whom had single-vessel RCA disease. With regard to the RV, 6 patients had nonvisualization, 30 had patchy visualization, and 15 had normal visualization in the stress thallium studies. Nonvisualization indicated 100% occlusion of RCA in 6 out of 6 patients. Patchy visualization indicated significant occlusion of the RCA in 25 out of 30 patients (83%), while normal visualization indicated a normal RCA in 13 out of 15 patients(86%). Normal visualization did not mean that the possibility of RCA disease could be excluded. When RV visualization data were added to LV images, the sensitivity for detecting RCA increased from 66% to 94% (P less than 0.05), the specificity decreased from 89% to 72% (P less than 0.1), and the predictive accuracy increased from 75% to 86% (P greater than 0.1).