Perforated colorectal neoplasms: correlation of clinical, contrast enema, and CT examinations

Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm.     

Long-term engraftment of normal and post-5-fluorouracil murine marrow into normal nonmyeloablated mice [see comments]

We report the successful long-term engraftment of normal male donor bone marrow (BM) transfused into noncytoablated female mice, challenging the assumption that "niches" need to be created for marrow to engraft. We have used chromosomal banding and Southern blot analysis to identify transplanted male marrow cells, and shown the long-term stability of the chimeric marrows. Balb/C, BDF1, or CBA-J female hosts (no irradiation) received for 5 consecutive days 40 x 10(6) male cells (per day) of the same strain, and repopulation patterns were observed. Parallel studies were performed using tibia/femur equivalents of normal marrow or marrow from Balb/C mice pretreated 6 days previously with 150 mg/kg 5-fluorouracil (5-FU). Chromosome banding techniques showed that 5% to 46% of marrow cells were male 3 to 9 months posttransplant with normal donor marrow. Southern blot analysis, using the pY2 probe, showed continued engraftment at 21 to 25 months posttransplant, ranging from 15% to 42% male engrafted cells in marrow. Normal donor male marrow engrafted significantly better than 5-FU-pretreated male marrow as shown 1 to 12 months posttransplant in non-cytoablated female recipients. Percentages of male engrafted cells in BM ranged from 23% to 78% for recipients of normal donor marrow and from 0.1% to 39% for recipients of 5-FU marrow. Mean engraftment for 6 mice receiving normal marrow was 38%, whereas that for 6 mice receiving post-5-FU marrow was 8%, as assayed 1 to 3 months posttransplant. At 10 to 12 months, mean engraftment for the normal donor group was 46%, compared with 16% for the 5-FU group. The patterns of engraftment with normal and 5-FU marrow were similar for spleen and thymus. These results show that long-term chimerism can be established after transplantation of normal donor marrow to normal nonirradiated host mice and indicate that marrow spaces do not have to be created for successful engraftment. They suggest that transplanted marrow competes equally with host marrow for marrow space. Finally, these data show that post-5-FU Balb/C male marrow is markedly inferior in the repopulation of Balb/C female host marrow, spleen, and thymus, and suggest that this population of cells may not be the ideal population for gene transfer studies.     

Left ventricular volumes measured by MR imaging

We assessed the potential of proton magnetic resonance (MR) imaging for accurately measuring left ventricular volumes using 15 latex casts of excised human left ventricles. The casts were submerged in water to stimulate the endocardial left ventricular cavity interface in in vivo imaging conditions. Tomographic image sections perpendicular to the long axis of the cast were obtained, spanning each cast from apex to base. Simpson's rule was used to calculate the cast volumes. Correlation between the actual cast volumes (as measured by the displacement method) and the calculated volumes using MR imaging for the 15 casts was excellent. Our data demonstrate that MR imaging accurately measures cardiac chamber volumes in this in vitro model.     

Inadvertent ligation of the left pulmonary artery

In five patients, aged 4 days to 20 months, the left pulmonary artery was inadvertently ligated at the time of attempted closure of the patent ductus arteriosus. The complication was recognized in these patients between 1 day and 5 years later from findings of chest radiography, two-dimensional echocardiography with spectral analysis of Doppler shifted echoes, and angiography. In three patients, the presence of asymmetric pulmonary blood flow on chest radiographs obtained after surgery initially suggested the diagnosis. In the other two patients with bronchopulmonary dysplasia, the diagnosis was made by means of two-dimensional echocardiography and Doppler spectra in one and angiography in the other. On angiograms, the left pulmonary artery distal to the ligation was visualized by delayed opacification from aortic collaterals in three patients and by means of pulmonary venous wedge injection in one. Radiographic and echocardiographic examination with Doppler spectra may permit prompt diagnosis and early correction of this complication.     

Head and neck lesions: MR-guided aspiration biopsy

Aspiration biopsy guided with computed tomography (CT) has long been a valuable tool in the evaluation of head and neck disease. The ability to obtain diagnoses without the need for surgery has had a significant effect on patient treatment. Magnetic resonance (MR) imaging is now rapidly replacing CT as the primary imaging study for many head and neck diseases. The standard stainless steel needles used for CT-guided biopsy are unsuitable for MR-guided biopsy because significant ferromagnetic artifacts obscure the underlying anatomy. A new needle has recently been designed specifically for use with MR imaging. This needle has far less magnetic susceptibility and therefore does not cause significant image distortion. The authors describe the use of this needle in MR-guided aspiration biopsy of a variety of lesions in the head and neck.     

Tongue and oropharynx: findings on MR imaging

Ten healthy subjects and 44 patients with diseases of the tongue or oropharynx were studied with magnetic resonance (MR) imaging. Axial, coronal, and sagittal images with a thickness of 4 mm were obtained with a pixel size of 0.75 X 0.75 mm on a 256 matrix. Nineteen of the patients underwent computed tomography (CT). Nine of those patients later had surgery, and the specimens were obtained for organ sectioning. These three studies as well as clinical history and physical examination findings were correlated. MR imaging was equal to or better than CT in those patients having both examinations. However, neither CT nor MR allowed recognition of histologic features or detection of microscopic spread of disease. Direct coronal and sagittal imaging planes on MR imaging allowed visualization of intrinsic tongue musculature, not possible with CT; this was important in recognizing subtle tumor extension. For these reasons, MR is the imaging method of choice for studying diseases of the tongue and oropharynx.