ABSTRACT
Multiple venous collateral pathways have been described in patients with superior vena cava obstruction. Systemic venous-to-pulmonary venous communication is the most unusual, having been described in a few cases of thoracic malignancy. In a patient with fibrosing mediastinitis radionuclide venography with 99Tcm-macroaggregated albumin demonstrated a systemic venous-pulmonary venous right-to-left shunt in addition to systemic and portal venous collaterals. It is apparent that systemic venous-to-pulmonary venous anastomoses may occur in the absence of malignant disease.
Subject(s)
Collateral Circulation/physiology , Mediastinitis/complications , Superior Vena Cava Syndrome/etiology , Adult , Female , Humans , Mediastinitis/diagnostic imaging , Mediastinitis/physiopathology , Radionuclide Imaging , Superior Vena Cava Syndrome/diagnostic imaging , Superior Vena Cava Syndrome/physiopathology , Technetium Tc 99m Aggregated Albumin , VeinsABSTRACT
The purposes of this study were to delineate the MR characteristics of CSF-like parenchymal or fissural cysts of the brain and to correlate them with the clinical findings. Clinical data and MR images of 34 patients with these abnormalities were reviewed. Pathologic correlation was not available. Two types of cystic lesions were identified and separated by location: medial temporal lobe cysts arising in or near the choroidal fissure (26 patients) and parenchymal or pseudoparenchymal cysts not related to the choroidal fissure (eight patients). The choroidal fissure cysts simulated intraparenchymal cysts on axial images but their extraaxial location was well portrayed on the coronal images. Choroidal fissure cysts had a characteristic spindle shape on sagittal images. The other cysts were found in the temporal lobe (seven patients) or thalamus (one patient) and appeared parenchymal but situated close to the subarachnoid space. These lesions were round or ovoid. There was no abnormal enhancement in 10 patients studied with gadopentetate dimeglumine. Coronal images were most useful, revealing the cysts as focal CSF-intensity lesions expanding the choroidal fissure of the temporal lobe. All the cysts appeared to represent incidental findings that did not correlate with the clinical signs and/or symptoms that prompted the imaging evaluations. The MR characteristics of CSF-like cysts are important to recognize so that they are not confused with other, more serious entities, such as intraaxial cystic tumors, infarctions, or parasitic lesions.
Subject(s)
Cerebral Ventricles/pathology , Cysts/diagnosis , Magnetic Resonance Imaging , Temporal Lobe/pathology , Adolescent , Adult , Aged , Brain Diseases/diagnosis , Child , Child, Preschool , Drug Combinations , Female , Follow-Up Studies , Gadolinium , Gadolinium DTPA , Humans , Image Enhancement/methods , Male , Meglumine , Middle Aged , Organometallic Compounds , Pentetic Acid , Tomography, X-Ray ComputedABSTRACT
The purposes of this study were to delineate the MR characteristics of CSF-like parenchymal or fissural cysts of the brain and to correlate them with the clinical findings. Clinical data and MR images of 34 patients with these abnormalities were reviewed. Pathologic correlation was not available. Two types of cystic lesions were identified and separated by location: medial temporal lobe cysts arising in or near the choroidal fissure (26 patients) and parenchymal or pseudoparenchymal cysts not related to the choroidal fissure (eight patients). The choroidal fissure cysts simulated intraparenchymal cysts on axial images but their extraaxial location was well portrayed on the coronal images. Choroidal fissure cysts had a characteristic spindle shape on sagittal images. The other cysts were found in the temporal lobe (seven patients) or thalamus (one patient) and appeared parenchymal but situated close to the subarachnoid space. These lesions were round or ovoid. There was no abnormal enhancement in 10 patients studied with gadopentetate dimeglumine. Coronal images were most useful, revealing the cysts as focal CSF-intensity lesions expanding the choroidal fissure of the temporal lobe. All the cysts appeared to represent incidental findings that did not correlate with the clinical signs and/or symptoms that prompted the imaging evaluations. The MR characteristics of CSF-like cysts are important to recognize so that they are not confused with other, more serious entities, such as intraaxial cystic tumors, infarctions, or parasitic lesions.
Subject(s)
Brain Diseases/pathology , Cerebrospinal Fluid , Choroid Plexus/pathology , Cysts/pathology , Magnetic Resonance Imaging , Adolescent , Adult , Aged , Child , Child, Preschool , Female , Humans , Male , Middle AgedABSTRACT
A case of spurious axillary uptake of I-131 proven to be caused by perspiration is presented. False-positive localizations of radioiodine, both pathologic and physiologic, are reviewed to avoid confusion of these entities with functioning thyroid carcinoma metastases.
Subject(s)
Axilla/diagnostic imaging , Iodine Radioisotopes , Sweat , Adult , Carcinoma, Papillary/diagnostic imaging , Carcinoma, Papillary/secondary , False Positive Reactions , Humans , Male , Radionuclide Imaging , Thyroid Neoplasms/pathologyABSTRACT
The scintigraphic appearances of 12 surgically proven cases of choledochal cyst were retrospectively reviewed. In seven of 12 cases, radionuclide accumulated in the choledochal cyst (i.e., the dilated common bile duct) in less than 1 hr. In three additional cases, delayed accumulation (1-24 hr) within the cyst was seen. In two of the 12 cases, no ductal activity appeared and the diagnosis of choledochal cyst could not be made, although in one of these two cases delayed images were not obtained. Other frequent findings included delayed or nonvisualization of the gallbladder (11 of 12) and the appearance of prominent intrahepatic ducts (five of 12). We conclude that hepatobiliary scintigraphy is a noninvasive test useful in the diagnosis of choledochal cyst.