Duplex sonography of the mesenteric vessels--a critical evaluation of inter-observer variability.

INTRODUCTION: The number of publications concerning mesenteric Doppler sonography (mesDS) is immense and does not correlate with the frequency of its use in clinical practice. This is astonishing since it provides real time blood flow (perfusion) information without side effects. Despite uncontrollable parameters like the technical limitations in some situations the optimization of (possibly) controllable parameters like standardization, production of normal values and reduction of the investigator variability by evaluating stable parameters could change the situation. PATIENTS AND METHODS: 10 investigators experienced in abdominal sonography ("DEGUM-Seminarleiter") performed mesenteric Doppler sonography in 5 healthy subjects with 5 different machines. RESULTS: The portal vein at the confluence and the common hepatic artery provide a significant portion of investigations with intromission angles of more than 60°. Values of diameter, resistance index and pulsatility index of the celiac trunc could be obtained with inter-observer variability values below 25 %. The proper and the common hepatic artery show no differences in inter-observer variability values, whereas the intrahepatic measure point of the portal vein showed a higher reproducibility. DISCUSSION: We define frame conditions for future mesenteric Doppler studies: the portal vein should be investigated at the intrahepatic measure point. Pathophysiological studies should refrain from velocity parameters except in the case of larger vessels running in a straight course towards the probe.

Percutaneous transhepatic cholangiography and drainage using extravascular contrast enhanced ultrasound.

BACKGROUND AND PURPOSE: Percutaneous transhepatic cholangiography and drainage (PTCD) is a common procedure for the diagnosis and treatment of benign and malignant biliary diseases. Ultrasound (US) is frequently used for the guidance of PTCD. Conventional fluoroscopy is applied to evaluate the biliary system, but delivers significant X-ray dosage to the patient and the interventional team. The purpose of this study is to test the ability of extravascular contrast-enhanced ultrasound (EV-CEUS) in US-guided PTCD to reduce or replace fluoroscopy. PATIENTS AND METHODS: 38 patients underwent PTCD. 2 - 4 mL doses of a SonoVue dilution were repeatedly injected to demonstrate correct needle and drainage positions in the biliary system and in the intestine during the intervention and during follow-up to screen for complications. The results were compared to those of conventional radiography. RESULTS: The success rate for cholangiography was 100 % for EV-CEUS and fluoroscopy each. 27/38 patients (71 %) received a ring catheter, 5/38 patients (13 %) received a metal stent. Only external drainage was possible in 6/38 patients (16 %) in the first session. In 50 % of them (3/38, 8 %) internalization was possible in the second attempt. With EV-CEUS the level of obstruction could be correctly diagnosed in 100 % of the patients. The degree of obstruction (complete/incomplete) could be correctly diagnosed in 37/38 patients (97 %). EV-CEUS was not able to demonstrate the guide wire. In 1/38 patient a hematoma appeared which was managed conservatively. Dislodgement was diagnosed in 2/38 (5 %) patients during follow-up by injecting EV-CEUS solution into the drain. Pleural injury with fistula could be demonstrated in 1/38 (3 %) patients. CONCLUSION: EV-CEUS can monitor the success of insertion of needle and catheter, demonstrate or exclude complications, and therefore significantly reduce fluoroscopy time in US-guided PTCD. Fluoroscopy is needed whenever subtle wire steering is necessary as in most cases when the intestinal position of the drain is sought. If only external drainage is necessary fluoroscopy can be omitted.

Contrast-enhanced ultrasound-guided percutaneous cholangiography and cholangiodrainage (CEUS-PTCD).

We present our experience with contrast-enhanced ultrasound-guided percutaneous transhepatic cholangiodrainage in eight patients with obstructive jaundice and failure of conventional endoscopic retrograde cholangiography. The intraductal application of the ultrasound contrast agent led to sufficient cholangiography in all patients. In one patient, after accidental dislocation of the bile duct drain, the leakage could be detected by demonstration of the passage of contrast agent into the perihepatic peritoneal space. Further studies are necessary to evaluate this new technique in a larger numbers of patients.

[Contrast enhanced ultrasound of the liver--state of the art]. / Kontrastverstärkte Ultraschalluntersuchung der Leber--Aktueller Wissensstand.

The diagnostic process, differential diagnosis and continuing routine follow-up of patients with focal liver lesions require an easily available, reliable and cost-effective diagnostic method. Ultrasound is a widely used method for the detection of liver lesions, but it has generally been regarded as inferior to contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI). Recent advances in contrast-enhanced ultrasound (CEUS) have improved the detection rate to a level similar to that attained with CT and MRI. Because of the high spatial resolution of ultrasound, CEUS can also detect metastases smaller than 1 cm. This has been demonstrated in several single-centre studies and recently also a European multi-centre study. This review focuses on the recent advances of CEUS in detecting and characterizing focal liver lesions.

[The infammatory pseudotumour -- an unusual liver tumour]. / Der inflammatorische Pseudotumor -- eine schwierige Differenzialdiagnose.

We report on a 49-year-old male patient who was suspected to have a malignant liver tumour with enlarged perihepatic lymph nodes because of CT and ultrasound scanning. To verify the diagnosis and procure a histological specimen, the patient underwent laparotomy. Histologically, an inflammatory pseudotumour could be confirmed. This is a rare disease which can present with fever, abdominal pain, vomiting and weight loss indicating malignancy or abscess. The definite diagnosis is often only verified by surgery.

Differentiation of focal nodular hyperplasia and hepatocellular adenoma by contrast-enhanced ultrasound.

Non-invasive differentiation of focal nodular hyperplasia (FNH) and hepatocellular adenoma (HCA) is difficult. The aim of this study was to assess the accuracy of contrast-enhanced phase inversion ultrasound to differentiate between histologically proven FNH and HCA, analysing the arterial and (early) portal venous phase. 32 patients with histological proven FNH (n=24) or HCA (n=8) have been included in this prospective study. Examination technique: Siemens Elegra, phase inversion harmonic imaging (PIHI) with low mechanical index (MI)<0.2-0.3 using SonoVue (BR 1). The contrast enhancing tumour characteristics were evaluated during the hepatic arterial (starting 8-22 s) and early portal venous phase (starting 12-30 s). The image analysis was performed by three examiners. In 23 of 24 patients with FNH the contrast pattern revealed pronounced arterial and (early) portal venous enhancement. Homogeneous enhancement was detected during the hepatic arterial phase in all eight patients with HCA. In contrast to patients with FNH, no enhancement was seen during the portal venous phase. In conclusion, contrast-enhanced phase inversion ultrasound demonstrated pronounced arterial and portal venous enhancement in patients with focal nodular hyperplasia. In contrast, after homogeneous enhancement during hepatic arterial phase, no enhancement during hepatic portal venous phase was detected in patients with hepatocellular adenoma. Therefore, this technique might improve the functional characterization of benign hypervascular focal liver lesions.

Sonographic characterisation of hepatocellular carcinoma at time of diagnosis.

BACKGROUND: Hepatocellular carcinoma (HCC) is a malignant liver tumour with a high prevalence world-wide. For screening procedures conventional transabdominal B-mode ultrasound and AFP determination are commonly used. We investigated 100 consecutive patients with histologically proven hepatocellular carcinoma in order to evaluate sonographic characteristics in unselected patients and to compare native and contrast-enhanced ultrasonographic techniques. PATIENTS AND METHODS: We investigated 100 consecutive patients with hepatocellular carcinoma at time of diagnosis with respect to echogenicity, patterns of vascularity, and portal/hepatic vein thrombosis. In addition to B-mode and native power Doppler sonography, contrast-enhanced power Doppler sonography with SHU 508A was used in 65 patients. RESULTS: The ultrasound appearance with conventional B-mode of hepatocellular carcinoma was hypoechoic in 48 % of the cases, isoechoic in 9 %, hyperechoic in 19 %, and in 25 % a mixture between hyper- and hypoechoic appearance was found compared to the surrounding liver tissue. Contrast-enhanced power Doppler sonography with SHU 508A changed the pattern of tumour vascularity in 27 % of patients into hypervascular, mainly in small lesions. DISCUSSION: At the time of diagnosis, the most commonly observed finding in hepatocellular carcinoma is that they appear hypervascular, independent of their size. The use of ultrasound contrast media should be considered to achieve characterisation of liver nodules in cirrhotic livers because they can improve the evaluation of tumour vascularity. Hypovascular HCC are found in about 10 % even after the administration of a contrast agent.

Improved characterisation of histologically proven liver tumours by contrast enhanced ultrasonography during the portal venous and specific late phase of SHU 508A.

PURPOSE: Ultrasound is reported to be relatively unreliable in the characterisation of liver tumours. The purpose of this study was to assess the ability of contrast enhanced phase inversion ultrasound (PIUS), a new highly sensitive contrast specific technique, performed during the liver specific phase of Levovist, to differentiate between benign and malignant lesions of the liver. PATIENTS AND METHODS: A total of 174 patients with histologically proven liver tumours were prospectively examined with conventional B mode ultrasound and two minutes after intravenous bolus injection of SHU 508A (Levovist). The examination technique comprised: Siemens Sonoline Elegra, phase inversion harmonic imaging (ECI); high mechanical index (1.2-1.7) using a delayed two minute post contrast scanning technique. RESULTS: In all patients with malignant disease, hypoechoic contrast enhancement was seen during the portal venous phase, and convincing but variably less demarcated in 13 patients with hepatocellular carcinoma compared with all patients with liver metastases. The liver tumours proved to be histologically benign in 95 patients and malignant in 79 patients. Homogenous contrast enhancement with a mainly isoechogenic appearance in the portal venous and liver specific late phase was seen in almost all patients with benign liver lesions with the exception of one patient with an inflammatory pseudotumour of the liver and five patients with abscesses. These six exceptions all demonstrated a hypoechoic appearance in the portal venous and liver specific late phase. DISCUSSION: The ability of unenhanced ultrasonography to characterise liver disease is known to be limited. PIUS performed during the portal venous and liver specific late phase of Levovist may differentiate between benign and malignant liver tumours in most cases, with the exception of, for example, abscesses, scars, necrosis, cysts, and calcifications, which need to be excluded clinically and by conventional B mode ultrasonography.

[Improved detection and characterisation of liver tumors with echo-enhanced ultrasound]. / Signalverstärkte Lebersonographie - Charakteristika einzelner Lebertumoren und Detektionsmöglichkeiten - eine Ubersichtsarbeit.

Contrast-enhanced ultrasound techniques represent the most challenging efforts in recent ultrasound developments. Contrast-enhanced imaging of the liver will be reviewed with respect to the literature and our own experience. Echo-enhancing agents, also known as ultrasound contrast media, have improved the accuracy of liver ultrasound within recent years. The characterisation of focal liver lesions which is possible by flow characteristics and the improved detection of liver tumors give special importance to the contrast agents. The agents consist of air or gas bubbles coated with different shell media. These micro-bubbles act as strong reflectors to the ultrasound beam enhancing the backscatter signal up to 30 dB. There are differences between blood pool agents and agents with a liver-specific late phase. The agents remain in the vessels during the vascular phase and lead to enhancement of different structures (arterial, capillary, portal venous, and sinusoidal perfusion). This is the first real-time imaging technique of liver lesions that allows a unique analysis of tumor perfusion. Liver tumors known to be hyperperfused in the arterial phase (e. g., focal nodular hyperplasia, hepatocellular carcinoma, and hyperperfused metastases) can be detected and characterised. Hypoperfused tumours (e. g., liver metastases of the gastrointestinal tract) can be recognised in the portal venous phase as less perfused "black spots". Due to of the recently available improved ultrasound technology and affordable ultrasound systems, a reduction in the use of computed tomography (CT) and magnetic resonance imaging (MRI) may be possible, allowing these important technologies to be available for other indications (e. g., brain, thorax).

The value of routinely performed ultrasonography in patients with Crohn disease.

BACKGROUND: In active Crohn disease (CD), abdominal ultrasound can demonstrate morphological changes in the bowel wall. By contrast, the role of ultrasonography in periods with no disease activity has never been evaluated. In this prospective study we investigated the outcome of routinely performed abdominal ultrasonography in CD patients irrespective of symptoms and disease activity. METHODS: 255 consecutive patients with chronic CD (117 M, 138 F, mean age (+/-s) 38 +/- 14) were evaluated by high-resolution ultrasonography of the bowel wall and abdomen. The findings were graded with respect to further diagnostic and/or therapeutic implications. In addition, the CD activity index (CDAI) was determined. In patients with pathological sonographic findings, complementary procedures (e.g. endoscopy, computed tomography, biopsy or operation) were performed to validate the suspected diagnosis. RESULTS: In 46/255 (18%) patients with CD, the diagnosis of a transmural inflammatory reaction (TMR) with or without fistula was made by ultrasonography. In respect of CDAI, 29/46 (63%) of these patients were graded as active disease (CDAI > 150) and 17/46 (37%) as inactive disease (CDAI < or = 150). Of the 17 patients with a TMR and CDAI < or = 150, 4 patients revealed interenteric fistula, 7 patients mesenteric or perirectal fistula, whereas 6 patients presented with a transmural mesenteric inflammatory reaction without fistula. All fistulae were confirmed by radiography. Ultrasonography of the remaining abdominal organs revealed pathological findings with further diagnostic implications in 25/255 (10%) patients and with therapeutic implications in 9/255 (4%) patients. CONCLUSION: Routinely performed ultrasonography of the abdomen reveals pathological findings with therapeutic implications not only in symptomatic but also in asymptomatic patients with CD. It can therefore be recommended as a screening tool for this group of patients.

[Imaging of the abdomen.

In the last decade, innovative ultrasound technology has become the primary imaging method in Gastroenterology. Compared to other imaging techniques (e. g., computed tomography and magnetic resonance imaging), conventional ultrasound images have the disadvantage of a restricted field-of-view (width), thus producing images that are not always easy to read. During the examination, the many mosaic-like single images obtained in real-time sonography must be mentally pieced together by the user, in order to obtain a complex 3-dimensional picture of the anatomical structure and its surrounding tissue. The extended field-of-view of the Panoramic Imaging technique is a useful addition to conventional diagnostic ultrasound since it provides the enhanced overview required for exact topography of surrounding structures. This is especially true for the Power Mode Panoramic Imaging technique that allows the trading of vessels over greater distances, e.g., in the extremities. Thus, accuracy and reproducibility of measurements in the examination of larger structures and organs has improved. A clearer representation of these anatomical structures increases understanding and acceptance by referring clinicians. An exact diagnosis based on ultrasound imaging will certainly result in cost savings in health-care, since the use of further imaging methods (and therefore the total examination time) may be reduced.

Videotape preparation of patients before hip replacement surgery reduces stress.

OBJECTIVE: Elective surgery represents a considerable source of stress for the patient. Many attempts have been made to prepare patients before surgery with the aim of reducing stress and improving outcome. This study used a novel approach to fulfill this aim by showing a videotape of a patient undergoing total hip replacement surgery, covering the time period from hospital admission to discharge, that strictly keeps to the patient's perspective. METHODS: Before elective total hip replacement surgery, 100 patients were randomly assigned to a control group or a preparation group; the latter group was shown the videotape on the evening before surgery. Anxiety and pain were evaluated daily for 5 days, beginning with the preoperative day, by means of the State-Trait Anxiety Inventory and a visual analog scale. Intraoperative heart rate and blood pressure, as well as postoperative intake of analgesics and sedatives, were recorded. Urinary levels of cortisol, epinephrine, and norepinephrine were determined in 12-hour samples collected at night for 5 nights, beginning with the preoperative night. RESULTS: Compared with the control group, the preparation group showed significantly less anxiety on the morning before surgery and the mornings of the first 2 postoperative days, and significantly fewer of them had an intraoperative systolic blood pressure increase of more than 15%. The pain ratings did not differ significantly between the two groups, but the prepared patients needed less analgesic medication after surgery. Prepared patients had significantly lower cortisol excretion during the preoperative night and the first 2 postoperative nights. Excretion of catecholamines did not differ significantly between groups. CONCLUSIONS: We conclude that use of the videotape decreased anxiety and stress, measured in terms of urinary cortisol excretion and intraoperative systolic blood pressure increase, in patients undergoing hip replacement surgery and prepared them to cope better with postoperative pain.

Cognitive-behavioral treatment in unselected rheumatoid arthritis outpatients.

OBJECTIVE: This trial was performed to evaluate the efficacy of an adjunctive cognitive-behavioral treatment compared with rheumatological treatment alone in unselected rheumatoid arthritis outpatients. DESIGN: A prospective randomized control design was used. Change in medication during treatment was controlled by matching therapy- and control-group subjects according to this change in medication, sex, age, duration of disease, and functional class. SETTING: A rheumatological outpatient clinic, University of Goettingen, Germany. PATIENTS: Fifty-five consecutive outpatients with a diagnosis of rheumatoid arthritis (age 52.7 years, 74.5% female, duration of disease 9.4 years) finished the study. INTERVENTIONS: Subjects received routine care by the rheumatologists and routine medical treatment. Cognitive-behavioral treatment subjects (n = 19) received adjunctive standardized cognitive-behavioral group treatment with 12 weekly sessions. OUTCOME MEASURES: Outcome measures included disease activity variables, pain variables (pain intensity, affective pain), psychological symptoms, and coping. RESULTS: Subjects mostly demonstrated an increasing disease activity during treatment; change in medication during treatment was necessary in some patients. In the cognitive-behavioral treatment group the course of rheumatoid arthritis seemed less progressive than in the control group. The core effects of cognitive-behavioral treatment pertain more to improved coping, emotional stabilization, and reduced impairment than to reduced pain intensity. Passive, emotion-focused coping, helplessness, depression, anxiety, affective pain, and fluctuation of pain are reduced, "Acceptance of Illness" is improved. CONCLUSIONS: Cognitive-behavioral therapy has proven an effective adjunct to standard treatment of rheumatoid arthritis outpatients. These effects were shown in an unselected sample with increasing disease activity and with comparable changes in medication during treatment. We recommend cognitive-behavioral treatment as an desirable adjunct to standard medical treatment of rheumatoid arthritis.

Analysis of GTP-binding proteins, phosphoproteins, and cytosolic calcium in functional heterogeneous human blood platelet subpopulations.

The biochemical basis for the functional heterogeneity of human blood platelets was investigated in terms of protein phosphorylation, cytoplasmic calcium ([Ca2+]i), the ratio of 46 and 50 kDa vasodilator-stimulated protein (VASP), and GTP-binding proteins (G-proteins). Platelets were fractionated by density. Comparing resting low-density platelets (LDP) to high-density platelets (HDP) revealed higher phosphorylation of proteins in the 47, 31, and 24 kDa ranges. A higher phosphorylation of the 20 kDa protein in LDP compared to HDP was related to an enhanced [Ca2+]i, an increased ADP-ribosylation of the inhibitory G-protein (G(i alpha1-3)) and rhoA, and a decreased ADP-ribosylation of the stimulatory G-protein (G(s alpha)). The differences in the ribosylation patterns of the subpopulations were not influenced by thrombin stimulation or exposure to prostaglandin E1 (PGE1). An 18 kDa phosphoprotein was more highly phosphorylated in resting HDP than in LDP. Thrombin exposure caused dephosphorylation of the 18 kDa phosphoprotein in the HDP, but generally increased phosphorylation of both HDP and LDP in the 47, 31, 24, and 20 kDa bands. Preincubation with prostaglandin E1 or sodium nitroprusside diminished the subsequent thrombin-induced increase in phosphorylation, particularly in HDP. In unstimulated HDP, the 50 kDa VASP phospho form was enhanced, whereas in unstimulated LDP the 46 kDa VASP dephospho form was increased. Our findings suggest that the functional heterogeneity of platelets is partly derived from differences in signal transduction mechanisms reflected in varying phosphoprotein patterns and G-protein properties of platelet stimulatory and inhibitory pathways.

The development of a novel series of (quinolin-2-ylmethoxy)phenyl-containing compounds as high-affinity leukotriene receptor antagonists. 3. Structural variation of the acidic side chain to give antagonists of enhanced potency.

This paper is the third in a series outlining the development of orally active sulfido peptide leukotriene antagonists containing a (quinolin-2-ylmethoxy)phenyl moiety. In this work the systematic variation of the acid side chain substituents led to dramatic and reproducible changes in the oral activity of these compounds, presumably due to alterations in their pharmacokinetic properties. The most potent compound identified, 5-[4-[4-(quinolin-2-yl-methoxy)phenyl]-3-methylbutyl]tetrazole (32), represents a convergence of good in vitro antagonist activity and a 3-10-fold improvement in oral potency over the current clinical candidate 2. The new findings from these optimization studies are as follows: oxygen substitution in the acid side chain was not necessary for antagonist activity, in vitro and in vivo activity was enhanced by alkyl or phenyl substitution on the gamma-carbon of the acid side chain of para-substituted (quinolin-2-ylmethoxy)phenyl derivatives, and free rotation about the side chain carbon atom adjacent to the (quinolin-2-ylmethoxy)phenyl ring was required for activity. The lead compound of this report (32) is a competitive inhibitor of [3H]LTD4 binding to receptor membrane purified from guinea pig lung (Ki = 12 +/- 3 nM) and of the spasmogenic activity of LTC4, LTD4, and LTE4 in guinea pig lung strip. Dosed orally in guinea pigs, this compound blocks LTD4-induced bronchoconstriction (ED50 0.8 mg/kg) and antigen-induced systemic anaphylaxis (ED50 = 1.2 mg/kg).

Effects of pressure on vesicle size, density, and distribution in the canine carotid arterial endothelium.

The purpose of the present experiment was to study the effects of internal hydrostatic pressure on vesicle size, density, and distribution in the canine carotid arterial endothelium by transmission electron microscopy. The pressures applied in this study were 0 (control), 40, 60, 80, 100, and 150 mm Hg. The results of transmission electron microscopy and computer analysis on the plasmalemmal vesicles of aortic endothelium showed that luminal, abluminal, and junctional vesicles all increased their diameter as the pressure was raised from 0 mm Hg, reaching a maximum at 80 mm Hg, and then decreased in size with further increases in pressure to 150 mm Hg. There was a significant difference in diameter among vesicles in different regions of the endothelium, with the diameter of luminal vesicles larger than those of abluminal and junctional vesicles. The densities of vesicles showed very little change from 0 to 80 mm Hg; but they increased markedly as the pressure was further raised from 80 to 150 mm Hg. These results indicate that pressure is an important mechanical factor governing the size and density of plasmalemmal vesicles in aortic endothelium.

Enhanced macromolecular permeability of aortic endothelial cells in association with mitosis.

Experiments were performed on thoracic aortae of 12 male Sprague-Dawley [corrected] rats to determine the statistical frequency of isolated leaks to Evans blue-albumin (EBA) conjugate at the level of individual cells and to assess the relationship of such leaks to the cell turnover process. Fluorescence microscopy was used to detect leakage of EBA around individual cells, and hematoxylin staining was used to identify cells in mitosis on the same specimens. Although endothelial cell mitosis is very rare in occurrence, 99% of the cells in the M phase were associated with EBA leakage. Since these dividing cells accounted for only one third of all cellular leakage sites, we concluded that significant leakage also occurred in other phases of the cell cycle, probably prior to and after the M phase, or during non-denuding desquamation.

Time-dependent effects of endotoxin on the ultrastructure of aortic endothelium.

The aortic endothelium from control and Escherichia coli (E. coli) endotoxin-treated rats and rabbits was examined by transmission and scanning electron microscopy. Following the intravenous injection of endotoxin, the animals were sacrificed at intervals ranging from 1 min to 4 hr. As early as 1 min after endotoxin, there was a widening of the subendothelial space (SES) and an increase in tortuosity of the internal elastic lamina (IEL). At 5 min, the tortuosity of the IEL increased to a peak value, and the SES showed an increase in the amount of smooth muscle cells (SMC). Initial endothelial damage occurred 5 min after endotoxin: SEM showed some spindle-shaped endothelial cells starting to peel from the underlying SES, and TEM showed some endothelial cells protruding or arching into the lumen. The new findings in this study are that endotoxin injection a) has a very rapid (less than 15 min) effect on rat and rabbit aortic endothelium, including localized endothelial injuries in the intima, and b) induces ultrastructural alterations also in the SES, IEL and portions of the tunica media. These effects were largely reversed within 1 hr after endotoxin administration, thus indicating that the endothelium and other components of the arterial wall can recover with great speeds.

Regional cerebral metabolic activity in the rat following experimental subarachnoid hemorrhage.

A new experimental model was employed to investigate alterations of cerebral metabolic activity in rats subjected to extensive subarachnoid hemorrhage (SAH). The hemorrhages were produced in anesthetized animals by inserting 0.37 ml fresh autologous arterial blood into the subarachnoid space. Rats that underwent sham operations received subarachnoid injections of mock CSF to study the effects of sudden raised intracranial pressure (ICP). Forty-eight hours after subarachnoid injection, the unanesthetized rats were given intravenous injections of [14C]2-deoxyglucose. Experiments were terminated 45 min later by decapitation, and the brains were removed and frozen. Regional brain metabolic activity was studied employing quantitative autoradiography. In comparison with control animals, cerebral metabolic activity was diffusely decreased following SAH. Statistically significant decreases in metabolic activity of less than 34% were observed in 17 of 30 brain regions studied. The largest percentage reductions were in regions displaying the highest basal metabolic rates. Subarachnoid injections of mock CSF also produced depression of cerebral metabolic activity, but quantitatively these changes were not as pronounced as in the hemorrhage group. These studies demonstrate regional changes in brain function following SAH. The data relate these changes to both the presence of blood in the subarachnoid space and sudden raised ICP.