Noninvasive diagnosis of coronary artery fistula by Doppler color flow mapping.

Sixteen patients with coronary artery fistula proved by coronary angiography or surgery were studied using two-dimensional echocardiography and Doppler color flow mapping. The coronary artery fistula drained into the right atrium in 4 patients, the right ventricle in 2 and the pulmonary artery in 10. The dilated coronary artery was visualized in 7 of the 16 patients with a fistula, as compared with none of the 40 control subjects. These 7 patients included 5 of 6 patients with a fistula draining into the right atrium or right ventricle and only 2 of 10 patients with a fistula draining into the pulmonary artery. Abnormal flow signals in the dilated coronary artery were visualized with Doppler color flow mapping in five of these seven patients. Color flow imaging visualized abnormal flow signals with mosaic appearance in the pulmonary artery in eight patients, the right atrium in four and the right ventricle in two. The chamber in which abnormal signals were detected corresponded with the entry site of the fistula by angiography. Intraoperative imaging during surgical repair was needed in two cases to confirm ligation of all arteries feeding into the fistula network. In conclusion, Doppler color flow imaging is diagnostically useful to visualize shunt flows originating from the opening or exit of a coronary artery fistula. Furthermore, intraoperative use of this technique may provide confirmation of successful surgical ligation of the fistula.

Direct visualization of ruptured chordae tendineae by transesophageal two-dimensional echocardiography.

To determine the value of transesophageal echocardiography in the detection of ruptured chordae tendineae, 28 patients who had surgical therapy for pure mitral regurgitation were evaluated prospectively by conventional transthoracic and transesophageal two-dimensional echocardiography. Seventeen patients (Group I) had ruptured chordae tendineae and 11 (Group II) had intact chordae tendineae. Transthoracic echocardiography detected ruptured chordae tendineae in 6 patients from Group I (sensitivity 35%) and flail leaflets in 11 patients from Group I (sensitivity 65%). Transesophageal echocardiography disclosed ruptured chordae tendineae in all 17 Group I patients (sensitivity 100%); the sensitivity was significantly higher than that of transthoracic echocardiography. No abnormal chordal echoes were visualized in any patient from Group II by either transthoracic or transesophageal echocardiography (specificity 100%). Transesophageal echocardiography is a highly sensitive method for detecting ruptured chordae tendineae and is superior to transthoracic echocardiography in establishing its diagnosis.

Left ventricular outflow tract to left atrial communication secondary to rupture of mitral-aortic intervalvular fibrosa in infective endocarditis: diagnosis by transesophageal echocardiography and color flow imaging.

Infection of the mitral-aortic intervalvular fibrosa occurs most commonly in association with infective endocarditis of the aortic valve. Infection of the aortic valve results in a regurgitant jet that presumably strikes this subaortic interannular zone of fibrous tissue and produces a secondary site of infection. Infection of this interannular zone then leads to the formation of subaortic abscess or pseudoaneurysm of the left ventricular outflow tract. This infected zone of mitral-aortic intervalvular fibrosa or subaortic aneurysm can subsequently rupture into the left atrium with systolic ejection of blood from the left ventricular outflow tract to the left atrium. This report describes the echocardiographic findings in three patients with pathologically proved left ventricular outflow tract to left atrial communication. Precise preoperative diagnosis is important, and this lesion should be differentiated from ruptured aneurysm of the sinus of Valsalva and perforation of the anterior mitral leaflet. Transthoracic echocardiography using color flow imaging and conventional Doppler techniques may show an eccentric mitral regurgitation type of signal in the left atrium originating from the region of the left ventricular outflow tract. However, transesophageal echocardiography provides an accurate preoperative diagnosis and should be used intraoperatively during repair of such lesions.

Role of two-dimensional echocardiography, pulsed, continuous wave color flow Doppler techniques in the assessment of ventricular septal rupture after myocardial infarction.

Two-dimensional echocardiography, pulsed and continuous wave Doppler techniques were used for the evaluation of 15 consecutive patients (9 men, 6 women; mean age 71 years, range 61 to 79) with ventricular septal rupture due to acute myocardial infarction (7 anterior, 8 posterior). Standard and modified off-axis 2-dimensional echocardiographic views from parasternal, apical and subcostal windows correctly identified this defect in 14 of the 15 patients. Pulsed Doppler echocardiography confirmed the presence of left-to-right-sided shunt by showing a high-velocity, aliased, systolic flow and a low-velocity diastolic flow in the right ventricle in 14 patients. Continuous wave Doppler echocardiography showed a high-velocity systolic and low-velocity diastolic flow signal of left-to-right shunt in 14 patients. Color flow Doppler imaging identified a left-to-right shunt in all 6 patients in whom it was performed. Doppler and 2-dimensional echocardiographic studies missed a small apical septal defect in 1 patient with anteroseptal myocardial infarction. Two-dimensional echocardiography correctly diagnosed right ventricular infarction in all 5 patients with posteroinferior infarction. Ventricular septal rupture and/or left-to-right-sided shunt was confirmed in all 15 patients by the following: surgical inspection in 11, necropsy in 3, left ventricular cineangiography in 5 and right-sided heart catheterization and oximetry data in 13 patients. Data indicate that 2-dimensional echocardiography correctly shows the precise location of septal rupture in most patients after acute myocardial infarction and allows assessment of left and right ventricular infarction and function.(ABSTRACT TRUNCATED AT 250 WORDS)

Accuracy of cardiac output estimation with biplane transesophageal echocardiography.

To evaluate the accuracy of cardiac output measurements with biplane transesophageal Doppler echocardiography, we examined 26 sets of observations in 14 patients using thermodilution technique as the standard. A mitral inflow method by single-plane combined the time-velocity integral of mitral inflow at the mitral annulus with the area of mitral annulus, assuming it to be a circular shape, by use of either the four- or the two-chamber view. With both views, a mitral inflow method by biplane combined the average of time-velocity integral of mitral inflow from the four- and the two-chamber views with the area of mitral annulus, assuming it to be an ellipsoid shape. The correlation coefficients between thermodilution and single-plane method of cardiac output were 0.81 (SEE = 0.72 L/min) and 0.85 (SEE = 0.79 L/min) for the four- and the two-chamber views, respectively. The correlation coefficient with biplane method was 0.93 (SEE = 0.47 L/min). Thus, biplane transesophageal Doppler echocardiography can be used for more accurate estimation of cardiac output.

Biplane transesophageal echocardiography: technique, image orientation, and preliminary experience in 131 patients.

Transesophageal echocardiography with use of a uniplane phased-array transducer with a transverse or horizontal scanning plane has become a well-established tool for evaluating cardiovascular diseases. Recent introduction of biplane probes has enhanced the diagnostic capability of this imaging technique. This article discusses the technique of biplane transesophageal echocardiographic examination and image orientation. The diagnostic value and advantages of various biplane transesophageal images of the heart, aorta, and aortic arch from various esophageal positions are described.

HTLV-I-associated myelopathy: acute progression and atypical MR findings.

We describe serial MR imaging findings in a patient with HTLV-I-associated myelopathy. The patient had acute progression of neurologic symptoms and exhibited swelling of the entire length of the spinal cord with increased T2 signal and contrast enhancement on MR imaging. The spinal cord became atrophic a few years later.

Neurenteric cyst with alteration of signal intensity on follow-up MR images.

SUMMARY: Intracranial neurenteric cysts are uncommon and usually have low intensity on T1-weighted MR images and high intensity on T2-weighted MR images. We report a case of a neurenteric cyst that was situated in front of the medulla oblongata and the size of which increased with alteration of MR signal from high to isointense compared with that of brain on T1-weighted images obtained 33 months after the initial MR images. We think that the signal change of the cyst was probably caused by a change of protein concentration.

Intraspinal extradural cysts communicating with adjacent herniated disks: imaging characteristics and possible pathogenesis.

We report two cases of intraspinal extradural cysts communicating with an adjacent herniated disk that we term "disk cysts." These cysts were well defined and homogeneous, and were present in the ventrolateral extradural space adjacent to a lumbar herniated disk. They had rim enhancement on contrast-enhanced MR images, and communication with a herniated disk was revealed by diskography.

The role of diffusion-weighted imaging in patients with brain tumors.

BACKGROUND AND PURPOSE: Diffusion-weighted images (DWIs) have been used to study various diseases, particularly since echo-planar techniques shorten examination time. Our hypothesis was that DWIs and tumor apparent diffusion coefficients (ADCs) could provide additional useful information in the diagnosis of patients with brain tumors. METHODS: Using a 1.5-T MR unit, we examined 56 patients with histologically verified or clinically diagnosed brain tumors (17 gliomas, 21 metastatic tumors, and 18 meningiomas). We determined ADC values and signal intensities on DWIs both in the solid portion of the tumor and in the peritumoral, hyperintense areas on T2-weighted images. We also evaluated the correlation between ADC values and tumor cellularity in both gliomas and meningiomas. RESULTS: The ADCs of low-grade (grade II) astrocytomas were significantly higher (P =.0004) than those of other tumors. Among astrocytic tumors, ADCs were higher in grade II astrocytomas (1.14 +/- 0.18) than in glioblastomas (0.82 +/- 0.13). ADCs and DWIs were not useful in determining the presence of peritumoral neoplastic cell infiltration. The ADC values correlated with tumor cellularity for both astrocytic tumors (r = -.77) and meningiomas (r = -.67). CONCLUSION: The ADC may predict the degree of malignancy of astrocytic tumors, although there is some overlap between ADCs of grade II astrocytomas and glioblastomas.

MR imaging of Wallerian degeneration in the brainstem: temporal relationships.

Degeneration of the myelin sheath and axon distal to the most proximal site of axonal interruption secondary to axonal disease has been called wallerian degeneration. On MR imaging, wallerian degeneration of the pyramidal tract can be observed as an abnormal signal intensity, showing prolonged T1 and T2 relaxation times that correspond to the corticospinal tract, with or without shrinkage of the ipsilateral cerebral peduncle and pons. Review of MR studies in 150 cases of supratentorial cerebrovascular accidents showed abnormal signal alterations in the ipsilateral brainstem in 33 of the cases. Abnormal intensity in the ipsilateral brainstem was seen as early as 5 weeks after the supratentorial ictus and was fully evident after 10 weeks in all 33 cases. Signal alterations were strongest at about 3-6 months when compared with alterations seen at 10 weeks or even 10 months after the ictus. Shrinkage of the ipsilateral brainstem appeared as early as 8 months and was demonstrated in all cases 13 months after the ictus. MR seems to be the most effective technique for early detection of wallerian degeneration and may provide insight into its pathophysiological and chemical changes.

An unusual middle fossa interdural epidermoid tumor. Case report.

The authors report an unusual case of an intracranial, interdural epidermoid tumor and cyst in a 72-year-old woman who presented with longstanding, mild numbness over her right cheek. She was initially treated conservatively, but on follow-up review the mass was found to have grown and evidence of hemorrhage was present, and therefore a subtotal resection was performed. This case should probably be classified as a paratrigeminal, interdural epidermoid cyst; this is the first known report in which magnetic resonance and computerized tomography images of such an entity are presented and discussed.

CT and MR imaging of cerebral tuberous sclerosis.

Tuberous sclerosis is a heredofamilial neurocutaneous syndrome, or phakomatosis, with multisystem involvement including the brain, kidney, skin, retina, heart, lung, and bone. The brain is the most frequently affected organ in tuberous sclerosis. Brain lesions in tuberous sclerosis are of three kinds; cortical tubers, white matter abnormalities, and subependymal nodules. We review the computed tomography (CT) and magnetic resonance (MR) features of the brain lesions in patients with tuberous sclerosis. CT clearly demonstrates calcified subependymal nodules. MR imaging demonstrates more clearly cortical, and white matter lesions than CT, since MR imaging shows excellent image contrast between various normal structures and high sensitivity in detecting pathological states due to intrinsic differences in proton density and in particular, in proton relaxation times of tissues. Possible pathogenesis of this disorder is also discussed.

Castleman's disease of the spleen: CT, MR imaging and angiographic findings.

Since Castleman and Towne [Castleman and Towne, Hyperplasia of mediastinal lymph nodes, New Engl. J. Med. 250 (1954), 26-30] first described hyperplasia of the mediastinal lymph nodes in 1954, many cases of Castleman's disease have been reported. Lesions originating in the spleen arc extremely rare, and we here describe the imaging appearances for such a case, and discuss with a brief review of the literature.

Idiopathic spinal cord herniation associated with intervertebral disc extrusion: a case report and review of the literature.

STUDY DESIGN: A case of idiopathic spinal cord herniation is reported, and the literature is reviewed. OBJECTIVE: To report a case of thoracic spinal cord herniation with a ventral dural defect, probably caused by thoracic disc extrusion. SUMMARY OF BACKGROUND DATA: Recently, reports of spinal cord herniation have been increasing. This increase can be attributed to the development of magnetic resonance imaging and increased awareness of this entity. However, the cause of the ventral dural defect remains unknown. METHODS: A 54-year-old woman had experienced Brown-Séquard syndrome for 2 years. Magnetic resonance imaging demonstrated an S-shaped anterior kinking of the spinal cord, with dilation of the dorsal subarachnoid space. RESULTS: After incision of the dural sac and gentle retraction of the spinal cord, a dural defect was recognized into which the spinal cord had herniated. An extruded disc was visualized through the defect at T3-T4. The ventral dural defect and the dorsal incision of the dural sac were repaired with a fascial graft from the thigh. CONCLUSIONS: Intraoperative findings suggest that the thoracic disc herniation in the current case was the probable cause of the ventral dural defect. Surgical reconstruction using double fascial graft under careful spinal cord monitoring resulted in a satisfactory neurologic recovery.

Thallium and FDG uptake by atelectasis with bronchogenic carcinoma.

We report a case of bronchogenic carcinoma with atelectasis studied by T1-SPECT and FDG-PET. In the carcinoma, abnormally high uptake of T1 and FDG were detected, but in the region of atelectasis, an abnormally high uptake of T1 with a relatively low uptake of FDG were observed. On quantitative analyses, the T1 retention indexes of the tumor and atelectasis were 29.7 and 42.0. The mean SUVs of FDG of the tumor and the atelectasis were 8.92 and 1.28. T1-SPECT could not distinguish the atelectasis from the carcinoma. FDG-PET was superior to T1-SPECT in this case in detecting malignancy and distinguishing it from atelectasis.

Two cases of chronic tonsillitis studied by FDG-PET.

We report two cases of chronic tonsillitis studied by FDG-PET. Symmetrical high FDG uptake by the tonsils was observed in both cases. On histopathologic examination of the resected tonsils, follicular hyperplasia was observed with proliferation of lymphocytes in the germinal centers. Increased glucose metabolism in active inflammation involving lymphocyte proliferation was thought to be a cause of high FDG uptake by tonsils in chronic tonsillitis.

Relatively high F-18 fluorodeoxyglucose uptake in paranasal sinus aspergillosis: a PET study.

We report a case of maxillary sinus (MS) aspergillosis studied by positron emission tomography (PET) with F-18 fluorodeoxyglucose (FDG) and by 67Ga-citrate (Ga) single photon emission computed tomography (SPECT). The FDG uptake existed in the lesion and along the inflammatory edematous mucous membrane of the MS. Ga uptake occurred not only in the lesion and in the mucous membrane but also in the MS. Relative quantification, the standardized uptake value (SUV) of the lesion showed relatively high FDG uptake (3.7). But in other reports, many malignant head and neck tumors had a SUV below 3.7. It was thought to be difficult to differentiate between aspergillosis and malignant head and neck tumors by FDG-PET.

Physiological FDG uptake in the palatine tonsils.

In clinical F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) studies of the head and neck region, remarkable symmetric tonsillar FDG uptake is sometimes observed. We determined the incidence and degree of tonsillar FDG uptake and investigated the significance of tonsillar FDG uptake. Between June 1998 and August 1998, we obtained informed consent from 17 patients who were scheduled to undergo a FDG-PET study for their own disease (11 men and 6 women; aged 22 to 77 yr) and who did not have head and neck disease to perform FDG-PET scanning of the head and neck region in addition to their target organs. The incidence and degree of tonsillar FDG uptake were determined. Remarkable tonsillar FDG uptake was found in 9 patients. The SUVs of these FDG uptakes ranged from 2.48 to 6.75, with a mean of 4.29 +/- 1.20 (SD). Tonsillar FDG uptakes in the remaining 8 patients were not remarkable, and their SUVs ranged from 1.93 to 3.31, with a mean of 2.46 +/- 0.45. Head and neck disease does not appear to have been responsible for the increase in tonsillar FDG uptake. Differences among tonsillar FDG uptake in these 17 patients without head and neck disease appear to reflect differences in activity of "physiological" inflammation of the palatine tonsils.

MR imaging of multiple sclerosis in the cervical cord.

This is a case of a 34-year-old woman with multiple sclerosis (MS) in whom an enlarged cervical spinal cord with long T1 and T2 relaxation times was demonstrated on MR images. This report seems to be the first description of MR imaging of MS with an enlarged spinal cord.