Abbott AxSYM Vancomycin II assay: multicenter evaluation and interference studies.

The authors evaluated the performance characteristics of the Abbott AxSYM Vancomycin II immunoassay in sera of patients with (n = 93 samples) and without (n = 327 patients) renal dysfunction. Correlation of vancomycin measurements with the Abbott AxSYM Vancomycin, Abbott TDx/TDxFLx, Syva enzyme-multiplied immunoassay technique (EMIT), DuPont automated chemistry analyzer (ACA), and high-performance liquid chromatography methods showed acceptable correlation as indicated by: slope values >0.95, r-values >0.97, y-intercepts <1.7 microg/ml, and S(y/x) ranging from 9% to 15% of the average vancomycin value. The AxSYM Vancomycin II assay showed acceptable correlation with AxSYM vancomycin, TDx/TDxFLx, and high-performance liquid chromatography methods in 93 samples from patients with renal dysfunction. This monoclonal antibody-based assay showed no apparent interference from the presence of human antimouse antibody (HAMA) or the microbiologically inactive vancomycin crystalline degradation product (CDP). The authors conclude that the AxSYM Vancomycin II assay showed satisfactory agreement with other methods tested in this study.

Periodicity and prediction of mania onsets in biopolar I affective disorders.

In studying the periodicity of mania onsets, cycle-oriented diagrams were made of the clinical course from 257 manic episodes analyzed retrospectively in 34 bipolar I manic-depressive patients for a period of about 5 years. Using these diagrams, the frequent period of mania onsets located in one-quarter of the follow-up period was pre-estimated, and the accordance ratio during a 25 month follow-up period was analyzed. The accordance ratio in all subjects was 39% (11/28) for the first episode and 35% (7/20) for the second episode. These ratios were not significantly different from the expected level (25%). The number of subjects was limited to 11 patients (10 rapid and 1 non-rapid cyclers) whose number of episodes used for the determination of the index cycle was eight or more. The accordance ratio was 64% (7/11) and 60% (6/10) for the first and second episodes, respectively. Their levels were significantly higher than those expected. Periodicity of mania onsets existed at least in rapid cyclers with abundant past data.

Acute aortic dissection with intramural hematoma: possibility of transition to classic dissection or aneurysm.

Acute aortic dissection with intramural hematoma has been believed to have a good prognosis, but we have encountered the transition of this entity to a classic dissection or aneurysm. We report the serial computed tomography (CT) features in 27 cases of acute aortic dissection with intramural hematoma. Eleven patients (40.7%) developed a classic dissection or aneurysm during follow-up. Four patients (14.8%) showed transition to a classic dissection without resolution of the intramural hematoma; each had a dilated ascending aorta measuring > 5 cm in diameter on the initial CT. One case (3.7%) developed an enlarging aneurysm without resolution of the intramural hematoma. In 19 cases (70.4%), the hematoma resolved; among these 19, the aortic diameter was significantly larger (p < 0.01) than those in a normal control group. Two of these 19 later developed an aneurysm, and four developed a classic dissection. This entity often (40.7%; 11 of 27) required surgical intervention or periodic follow-up CT examinations, particularly with a dilated ascending aorta of > 5 cm in diameter.

[A case of renal pseudotumor caused by pyelonephritis].

A case of renal pseudotumor due to pyelonephritis is reported. A 70-year-old female was admitted to our hospital for the evaluation of right renal mass in pyelogram. She had had episodes of pyelonephritis many times. Computed tomography (CT) revealed poorly marginated low density mass that exhibits inhomogenous enhancement with contrast medium. Angiography showed an avascular mass. On magnetic resonance imaging (MRI), the mass was isointensity or slightly low intensity on T1 weighted scan, while it showed low intensity on T2 weighted scan. The patient died from small cell carcinoma in the lung two years later. Autopsy was performed and no malignancy was found in the kidney. MRI was useful to differentiate such inflammatory change from renal tumor, which is mostly high intensity on T2 weighted scan.

[Congenital arteriovenous malformation of the kidney: report of two cases--detection by digital subtraction angiography with carbon dioxide].

Two cases of arteriovenous malformation of the kidney were reported. The first case was a 19-year-old female, complaining of right flank pain and gross hematuria. Right selective renal arteriography revealed a 2 x 1.5 cm large cisoid type arteriovenous malformation at the most distal region of the lower branch of the renal artery. Transcatheter embolization, using Gelfoam and absolute ethanol, was successfully done, which was confirmed with repeated digital subtraction angiography with carbon dioxide (CO2-DSA). The second patient was a 55-year-old female with past history of right idiopathic renal bleeding, complaining of right flank colicky pain and gross hematuria. Right selective renal arteriography was done without any pathological findings, while CO2-DSA documented an arteriovenous malformation in the hilar region. Transcatheter embolization was not done, because the malformation seemed to be proximally located. Thus CO2-DSA was thought to be a reliable method in the diagnosis of arteriovenous fistula.

Periodicity of episode occurrences in rapid cycling affective disorders.

We analyzed the medical records of nine patients with severe rapid cycling affective disorders (RCAD), and determined the cycle of mania occurrences by calculating the period between two successive onsets of mania for each patient. Using the cycle as the index we devised a cycle-oriented diagram by dividing the observation period by the index cycle, and visually studied the mode of episode occurrences. In seven patients, the onset of mania generally followed the index cycle, but sometimes shifted from the day estimated by the index cycle. The shift seemed to be caused by a cycle other than the index cycle, which appeared temporarily in the course. The period between two successive onsets of mania was often several times longer than the index cycle length. In patients with RCAD, some sort of periodic rhythms may possibly control the course of episode occurrences on a continuing basis.

[The analysis of superselective catheterization technique; transcatheter segmental arterial embolization using lipiodol for hepatocellular carcinoma].

The practical limitations of catheters used for infusion were studied by their types in 47 patients with hepatocellular carcinoma who were treated by Segmental Lp-TAE. For catheterization into the arterial branches of S5 and S8, a coaxial infusion catheter was helpful. However, a coaxial infusion catheter was seldom used for catheterization into the arterial branches of S6 and S7. For infusion into vessels having diameters of less than 1.9 mm at the tip end of the catheter, positive use of a coaxial infusion catheter is strongly recommendable. A Tracker-18 catheter was especially helpful for catheterization into the vessels of S5.

[Transarterial hepatic embolization of metastatic liver cancers with reference to 17 cases of survival for more than 2 years].

The evaluation of TAE was studied for 73 patients with metastatic liver cancers but without metastasis in other organs, who were treated with initial TAE more than 2 years ago. Seventeen patients survived for more than 2 years. The primary lesions consisted of colon cancer in 9 patients, the Langerhans islet cell tumor of the pancreas in 4, gastric cancers in 2, breast cancer in 1 and leiomyosarcoma of the colon in 1. The overall 2-year survival rate calculated by the direct method was 23.3% and mean survival period was 15.8 months. The prognosis was good in H1 and V3. Lp-TAE produced better effects but no statistically significant difference was found between the 2-year survivals by Lp-TAE and by GS-TAE.

Improvement of T2-weighted images of central nervous system by motion artifact suppression technique (MAST).

Standard spin echo sequences of MRI with and without motion artifact suppression technique (MAST) were compared in 45 paired images of brain and 21 paired images of spine. The images were obtained on a Picker 1.5 T system with TR = 2 sec and TE = 100 or 120 msec. MAST is a method of refocusing transverse magnetization at echo time by modification of the gradient waveforms. Transverse, coronal, and sagittal planes of brain were compared in 10 paired images obtained from adults and five paired images from children. The spine was studied in sagittal images, 11 cervical images of adults, five lumbar images of adults, and five lumbar images of children. MAST was proven to be valuable not only for the detection of lesions but also for picturing anatomical details as in MR-cisternography and MR-myelography and the effects of iron ions. MAST improves significantly the quality of T2-weighted images, especially in children.

[Partial volume effect in MRI--a phantom study].

According to the direction and the thickness of the imaging slice in tomography, the border between the tissues becomes unclear (partial volume effect). In the present MRI experiment, we examined border area between fat and water components using phantom in order to investigate the partial volume effect in MRI. In spin echo sequences, the intensity of the border area showed a linear relationship with composition of fat and water. Whereas, in inversion recovery and field echo sequences, we found the parameters to produce an extremely low intensity area at the border region between fat and water. This low intensity area was explained by cancellation of NMR signals from fat and water due to the difference in the direction of magnetic vectors. Clinically, partial volume effect can cause of mis-evaluation of walls, small nodules, tumor capsules and the tumor invasion in the use of inversion recovery and field echo sequences.

[The usefulness of motion artifact suppression technic (MAST) in the MRI diagnosis of liver tumors].

The usefulness of motion artifact suppression technique (MAST) in the MRI diagnosis of liver tumors was assessed. Spin-echo with MAST was superior in lesion detection and contrast-to-noise ratio to conventional spin-echo. Its usefulness was verified. As the portal vein is delineated frequently as a high signal area, the portal structure up to the third branches was distinctly visualized. It was found helpful for the segmental diagnosis of the liver. However, careful attention is needed in the diagnosis of portal vein thrombosis.