Imaging diagnosis of obstructive jaundice.

In the past, before the development of biochemical tests for serum enzymes, differentiation between obstructive (surgical) and parenchymal (medical) jaundice was difficult. It was based mainly on patient history, physical examination and the experience of the physician, and the definitive diagnosis depended on surgical exploration. Even with known serum aminotransferase and alkaline phosphatase levels, a distinction between the two types of jaundice was not always certain. Then came the era of new imaging techniques. With the development of direct cholangiography followed by x-ray CT and real-time ultrasonography (US), differential diagnosis of surgical and medical jaundice is no longer a problem. In the clinical setting, the current issue is how quickly and how less invasively the diagnosis could be made. In this chapter, current imaging diagnosis in patients with obstructive jaundice will be discussed, along with its differentiation from medical jaundice.

Anti-G training of Japanese Air Self Defense Force fighter pilots.

Recently developed high-performance fighter aircraft (HPF) are capable of producing high sustained +Gz (HSG) with a rapid onset rate. This G-producing capability is now beyond human physiologic G tolerance. Many techniques to raise the tolerance to HSG have been used operationally. In order to cope with HSG effectively, the Japanese Air Self Defense Force has given high-G training for certain fighter pilots since 1982. So far, 138 pilots (62 F-15 Trainees, 76 F-4 Trainees) have completed centrifuge training at our laboratory. The 1-week program consists of: physical examination and briefing on high-G stress and its protective methods on day 1; centrifuge rides in two basic patterns--a tracking performance and a simulated aerial combat maneuver (SACM)--during the period from day 2-5; and debriefing and questionnaires on day 6. Gradual onset run (GOR) relaxed tolerance is + 5.5 +/- 0.7 Gz and rapid onset run (ROR) relaxed tolerance is + 4.9 +/- 0.6 Gz (n = 126). The difference in G tolerance between F-15 and F-4 trainees was not significant in either GOR or ROR. Loss of consciousness (LOC) occurred in 18 F-15 trainees and 15 F-4 trainees during basic patterns but all F-15 trainees met the training goal and completed the SACM pattern on day 5 without LOC. More than half of the trainees developed a variety of arrhythmias, including PVC, SVPC, A-V dissociation, S-A block, and atrial fibrillation (AF). The AF case developed WPW syndrome and atrial fibrillation followed by LOC during a 4-G warm-up pattern.(ABSTRACT TRUNCATED AT 250 WORDS)

[The distribution of solutions in the epidural space].

In 21 patients the distribution within the epidural space of epidurally injected 99mTc-DTPA was assessed. The gamma emissions from the epidural space were measured externally with the patients in supine position by use of a gamma camera. The recordings over the patient's back were stored in digital computer for 60 min. The results were as follows; 1) The spread of the radionuclide was mainly to cephalad direction, and seldom crossed the L5 level to sacral region. 2) The solution injected in the epidural space would distribute to less resistant compartments and the spread depends on the power of injection, negative pressure in the high epidural space and capillary pressure. 3) The elimination half-life of the injected radionuclide was between 1 to 17 min depending on the region in the epidural space. 4) The solution injected in the epidural space may penetrate dura mater at the ink cuff area and local anesthetic agents may affect the spinal nerve roots in the subarachnoid space rather than at the extra-dural space. 5) With continuous infusion technique the diffusion and penetration of the local agent through the dura mater are facilitated and more profound anesthetic effects would be expected. In clinical practice the utilization of the continuous infusion method should be considered along with the bolus injection.

[Clinical evaluation of SPECT in cerebrovascular disease].

In 131 patients with cerebrovascular disease, regional cerebral blood flow was determined by 123I-IMP (N-isopropyl (123I)-iodoamphetamine) or 99mTc-HM-PAO (99mTc (d, l)-hexamethyl propyleneamine oxime) SPECT and findings were compared with those of X-CT or MRI. The perfusion deficit detected by SPECT was larger than the deficit by X-CT or MRI in every cases. The perfusion deficit area was more clearly demonstrated by SPECT than by X-CT or MRI in patients with acute cerebral infarction. The hypoperfusion area determined by 123I-IMP SPECT was wider than that by 99mTc-HM-PAO SPECT. The crossed cerebellar diaschisis was observed in 56 out of 131 cases (43%). The results of operation were quantitatively evaluated by 123I-IMP SPECT in 25 patients.

Frequency of abnormalities detected by abdominal ultrasound among Japanese adults.

Abdominal ultrasound examination was given to 715 (566 male and 149 female) adult non-manual workers in Tokyo as part of their annually required medical check-up. Gross abnormalities were found in 44.5% of males and 34.2% of females. The most common finding was fatty liver (15.2%), seen four times as frequently in males as in females. There were 93 elevated lesions in the gall-bladder in 56 subjects (7.8%); some required follow-up examinations because malignancy could not be excluded. Small cystic lesions were frequently seen in the kidney (6.4%) and in the liver (4.8%). Gallstones were found in 3.4%. Mild splenomegaly occurred in 3.4%. Ten mass lesions, 8 hyperechoic and 2 hypo-echoic, were found in the liver, but subsequent imaging studies showed them to be benign haemangiomas. Other changes found included calcific lesions in the liver (2.1%) and in the spleen (0.4%), renal stones (2.0%), thickened wall of the gall-bladder (3.2%), intramural stones (0.8%) and debris/sludge (0.4%) in the gall-bladder, dilated pancreatic duct (0.7%) and common bile duct (0.3%), liver cirrhosis (0.4%), hydronephrosis (0.1%), enlarged pancreas (0.1%), small pancreas (0.1%), ovarian tumour (0.1%), uterine tumour (0.1%), abnormally shaped kidney (0.1%) and situs inversus (0.1%). It was concluded that abdominal ultrasound is an important examination for a mass screening or a physical check-up commonly practised as the 'human dock' for adults in Japan.

[Reappraisal of the clinical usefulness of transabdominal ultrasonography for advanced colon cancer--a study of tumor detection].

We evaluated the detectability of colon cancer by using transabdominal ultrasonography (US). Fifty-three cases of proven advanced colon cancer were examined in this study. Screening by US was carried out in 27 of 53 cases and US was performed in all cases after the definite diagnosis. Lesions of the colon were examined by using a 3.5 MHz convex and 5 MHz or 7.5 MHz linear probe (Yokogawa RT-2800, RT-4600). Localized hypertrophy of the irregular wall of more than 10 mm or massive tumor without the normal layered structure was defined as colon cancer on US. The rate of detection by screening test was 52%. The detection rate by US after definite diagnosis was 75%. A high detection rate was obtained in cases with a tumor diameter of more than 4 cm. Eight of 13 cases which were not detected by the screening test were visualized by US after definite diagnosis. US examination is useful for the detection of certain extended lesions of colon cancer. With technical improvements of the examination method, it is considered that cancer in the gastrointestinal tract may be discovered early on screening tests using US.