Multiple enhancing lesions detected on dynamic helical computed tomography-mammography

OBJECTIVES: To review pathologic diagnoses of multiple enhancing lesions in a unilateral breast detected on dynamic helical computed tomography (CT)-mammography and to correlate imaging findings with pathologic results. METHODS: From May 1998 to July 2001, preoperative contrast-enhanced helical CT scanning of the breast was performed in 200 female patients clinically diagnosed with breast cancer. The patients were scanned in the prone position in a specially designed CT-compatible device, with rapid intravenous bolus injection of 100 mL contrast material. Three-dimensional maximum intensity projection images were reconstructed. The cases with multiple enhancing lesions in a unilateral breast were retrospectively reviewed. The maximum diameter of the largest stain in each breast was measured, the patterns of multiple enhancing lesions were classified, and imaging findings were correlated with surgical and pathologic outcomes. RESULTS: Twenty-five of 200 (12.5%) patients (age range: 39-86 years, mean age: 56 years) showed multiple stains on CT-mammography. Two patients showed multiple stains in bilateral breasts. The maximum diameter of the largest stain in each breast ranged from 5 to 55 mm (average: 22 mm). Among cases with multiple stains, 21 (78%) were shown to be invasive ductal carcinoma with multiple satellite cancer nodules. Four cases were ductal carcinoma in situ with multiple satellite nodules. One case revealed multiple fibroadenomas, and another showed intraductal papilloma. CONCLUSIONS: Multiple enhancing lesions on CT-mammography in patients with breast cancer were relatively common, and most of them represented multiple cancer lesions. Dynamic CT-mammography is potentially useful in evaluating the spread of breast cancer.     

Perioperative cerebral ischemia and the possibility of neuroprotection by inhalational anesthetics

Deteriorated neurological outcome is not rare after major surgeries. With aging of the surgical population in Japan, an increasing frequency of perioperative cerebral ischemia is expected. To avoid neurological deterioration after surgery and general anesthesia, especially in high-risk patients, it is important to provide appropriate CNS-oriented anesthesia management. Controlling factors such as cerebral perfusion pressure, arterial blood gases, blood glucose concentration and body temperature may influence brain metabolism and neurological outcome. Inhalational anesthetics may also play an important role in perioperative neurological management, because numerous studies have demonstrated some degree of neuroprotective effect with halothane, sevoflurane, desflurane and isoflurane. Among these inhalational anesthetics, isoflurane has been most extensively studied regarding neuroprotection against cerebral ischemic insult. Although no clinical outcome trials have been performed, both in vivo and in vitro studies have consistently shown that the isoflurane provides neuroprotection. However, it is also suggested that factors such as sympathetic reactivity, brain temperature, anesthetic dosage, timing of anesthetic administration, and co-administration of nitrous oxide might affect the neuroprotective effect of isoflurane.     

Postoperative recurrence of venous thromboembolism in patients with episodes of preoperative thromboembolism

BACKGROUND: Venous thromboembolism (VTE) has become a major health problem in Japan. METHODS: We examined, postoperative recurrence of VTE in patients with preoperative venous thromboembolic events and evaluated factors that are relevant to the occurrence of postoperative VTE. RESULTS: Forty-four cases out of 38500 had been diagnosed preoperatively as having VTE in the period of 1995-2001 at Kitasato University Hospital. Postoperative VTE was detected in four patients (9%) out of these 44 cases. Patients who had thrombophilia (antiphosholipid syndrome) or recent episode of VTE within 1 month were higher in the incidence of postoperative recurrence of VTE than the others. Temporary infra-vena cava filters were placed to prevent pulmonary thromboembolism in twelve patients. In 8 of the patients, thrombi were detected in or at the filter before explantation. Three patients (7%) had undergone thrombolysis therapy. Postoperative VTE was not found in patients who had already received anticoagulant therapy (warfarin) for 3 or more months. CONCLUSIONS: It is concluded that newly developed VTE occurred perioperatively in 9% of patients with preoperative VTE, and that thrombophilia and a recent episode of VTE were considered as risk factors of perioperative VTE. Temporary infra-vena cava filters are a valuable device for prevention of postoperative pulmonary thromboembolism.     

A case responding to weekly paclitaxel (TXL) therapy as third line chemotherapy for scirrhous type gastric cancer

A 67-year-old female was admitted to our hospital in May, 2001 for examination. She was diagnosed with advanced gastric cancer that was inoperable due to peritoneal dissemination. Seventeen courses of sequential MTX and 5-FU therapy, and 2 courses of TS-1 plus CDDP were carried out. A partial response (PR) and prolonged NC were obtained after these chemotherapies. However, pleural effusion and ascites appeared again, and we diagnosed progressive disease. As a third line chemotherapy for this patient, paclitaxel (TXL) was administered. Treatment consisted of two 3-week courses of paclitaxel 70 mg per m2 on day 1 of each week, with a 1-week break between the courses. Two weeks after the start of this therapy, pleural effusion and ascites had completely disappeared. Paclitaxel is considered to be promising for advanced gastric cancers, as second or third line chemotherapy with paclitaxel for patients with inoperable gastric cancer seems to be effective in improving QOL.     

Involvement of NMDA receptors in Zif/268 expression in the trigeminal nucleus caudalis following formalin injection into the rat whisker pad

We investigated the involvement of N-methyl-D-aspartate (NMDA) glutamate receptor in the expression of the proteins Zif/268 and c-Fos elicited by painful stimuli. To this purpose, the effect of the administration of MK-801, an NMDA receptor antagonist, on Zif/268 and c-Fos expression following a noxious stimulus, represented by formalin injection into the whisker pad of rats, was examined in neurons of the trigeminal nucleus caudalis. Furthermore, the co-localization of formalin injection-evoked Zif/268 and c-Fos expression and subunit 1 of the NMDA receptor (NR1) was studied in this nucleus. Zif/268 or c-Fos immunoreactivity elicited by formalin injection was significantly reduced by pretreatment with MK-801 in the superficial layer of the trigeminal nucleus caudalis; more than 40% of the neurons expressing Zif/268 and c-Fos in this layer were also immunolabeled by NR1. On the other hand, there was little effect of MK-801 administration on Zif/268 and c-Fos immunoreactivity in the nucleus proprius and deep lamina V of the trigeminal nucleus caudalis, while most neurons expressing Zif/268 or c-Fos in these two regions were labeled by NR1. These results point out differences between the superficial and deeper layers of the trigeminal nucleus caudalis in the involvement of NMDA receptor in the mechanisms underlying the expression of protein products of immediate early genes induced by painful stimuli.     

Venodilator effects of adenosine triphosphate and sodium nitroprusside; Comparisons during controlled hypotension

Adenosine triphosphate as well as sodium nitroprusside has been used for hypotensive anesthesia. The purpose of this study was to examine the possibility that two hypotensive drugs may exert different effects on venous capacitance during controlled hypotension. In rats anesthetized with ketamine, mean arterial pressure was lowered to 50mmHg by intravenous infusion of adenosine triphosphate or sodium nitroprusside. Venous capacitance was assessed before and during induced hypotension by measuring the mean circulatory filling pressure (MCFP). MCFP was measured after briefly arresting the circulation by inflating an indwelling balloon in the right atrium. MCFP was lower during adenosine triphosphate-induced as well as sodium nitroprusside-induced hypotension as compared with the respective value at control (P < 0.01 for adenosine triphosphate and sodium nitroprusside). However, the decrease in MCFP by adenosine triphosphate (0.8 ± 0.1mmHg) was less (P < 0.01) than that by sodium nitroprusside (2.3 ± 0.3mmHg). These results suggest that at a comparable level of arterial hypotension venodilator effect of adenosine triphosphate was less than that of sodium nitroprusside. Less venodilatation during adenosine triphosphate-induced hypotension may contribute to the maintenance of cardiac output during hypotensive anesthesia.(Hoka S, Takeshita A, Aishima K et al.: Venodilator effects of adenosine triphosphate and sodium nitroprusside; comparisons during controlled hypotension. J Anesth 1: 144–147, 1987)     

Intracellular potential of medullary reticular neurons during sleep and wakefulness

Intracellular records were obtained in the chronic cat from neurons of the nucleus reticularis gigantocellularis (NGC) during naturally occurring sleep and wakefulness. When wakefulness and quiet sleep was compared with active sleep, the membrane potential level of NGC neurons gradually decreased; a depolarized membrane potential was maintained tonically and selectively throughout active sleep. These data support the concept that NGC neurons assist in the generation of somatic atonia during active sleep and suggest that this state-dependent inhibitory function may be controlled by the nucleus pontis oralis as part of the general phenomenon of reticular response reversal.