A method for the monitoring of metal recrystallization based on the in-situ measurement of the elastic energy release using neutron diffraction.

A method is proposed for the monitoring of metal recrystallization using neutron diffraction that is based on the measurement of stored energy. Experiments were performed using deformed metal specimens heated in-situ while mounted at the sample position of the High Resolution Powder Diffractometer, HRPD (ISIS Facility), UK. Monitoring the breadth of the resulting Bragg lines during heating not only allows the time-dependence (or temperature-dependence) of the stored energy to be determined but also the recrystallized fraction. The analysis method presented here was developed using pure nickel (Ni270) specimens with different deformation levels from 0.29 to 0.94. In situ temperature ramping as well as isothermal annealing was undertaken. The method developed in this work allows accurate and quantitative monitoring of the recrystallization process. The results from neutron diffraction are satisfactorily compared to data obtained from calorimetry and hardness measurements.

Benefit of the Vittel criteria to determine the need for whole body scanning in a severe trauma patient.

OBJECTIVE: To evaluate the use of the Vittel criteria in addition to a clinical examination to determine the need for a whole body scan (WBS) in a severe trauma patient. MATERIALS AND METHODS: Between December 2008 and November 2009, 339 severe trauma patients with at least one Vittel criterion were prospectively evaluated with a WBS. The following data were collected: the Vittel criteria present, circumstances of the accident, traumatic injury on the WBS, and irradiation. The original intent to prescribe a computed tomography (CT) scan (whole body or a targeted region), based solely on clinical signs, was specified. RESULTS: Injuries were diagnosed in 55.75% of the WBS (n=189). The most common Vittel criteria were "global assessment" (n=266), "thrown, run over" (n=116), and "ejected from vehicle" (n=94). The multivariate analysis used the following as independent criteria for predicting severe traumatic injury on the WBS: Glasgow score less than 13, penetrating trauma, and colloid resuscitation greater than 11. Based solely on clinical factors, 164 patients would not have had any scan or (only) a targeted scan. In that case, 15% of the severe injuries would have been missed. CONCLUSION: Using the Vittel criteria to determine the need for a WBS in a severe trauma patient makes it possible to find serious injuries not suspected on the clinical examination, but at the cost of an increased number of normal scans.

Analysis of the French health ministry's national register of incidents involving medical devices in anaesthesia and intensive care.

This study details all incidents involving medical devices used in anaesthesia and intensive care reported to the relevant authorities in France in 1998. There were 1004 reports during that year. Incidents were classified as serious (harmful to patients) in 11% of cases; death resulted in 2% of cases. Equipment for ventilation and infusion, and monitors of all kinds, accounted for most of the reports, representing 37%, 30% and 12%, respectively, of all reports. The leading causes of failure varied according to the category of device. User errors, quality control problems during production of the device and design faults were the three main causes. The problems identified during the study period enabled the faulty medical devices to be improved in 12-44% of cases. We conclude that post-marketing vigilance is a useful way of improving the quality of medical devices.

[Anisakiasis, rare pseudotumor colonic involvement. Apropos of a case]. / Anisakidose, une localisation colique pseudotumorale rare. A propos d'un cas.

History taking should search for intake of raw or uncooked fish in patients with acute abdominal symptoms. The colon is an uncommon localization of anisakiasis. We describe the case of a 31-year-old man with acute abdominal pain whose abdominal CT scan showed a pseudotumoral formation of the colon. History taking and endoscopic ablation gave the diagnosis of anisakiasis. Whole worm extraction led to restituo ad integrum or the colonic wall.

-The effect of desflurane on cerebral blood flow velocity and cerebrovascular reactivity to CO2 in children-. / Effets du desflurane sur les vélocités sanguines cérébrales et la réactivité cérébrovasculaire au CO2 chez l'enfant.

OBJECTIVE: To assess in children with a transcranial Doppler the effect on cerebral blood flow velocities of desflurane, whose cerebral vasodilator effects have been studied in animals and in adults with intracranial lesions. STUDY DESIGN: Prospective clinical study. PATIENTS: Ten healthy children, mean age: 3.4 yr, ASA physical class 1, undergoing minor urologic surgery, were included in this study. METHOD: Induction was obtained with atropine 10 micrograms.kg-1, fentanyl 3 micrograms.kg-1 and propofol 3 mg.kg-1. Endotracheal intubation was facilitated by atracurium 0.3 mg.kg-1. Mechanical ventilation, with a 50% air/oxygen mixture was adjusted to achieve an end-tidal CO2 (PETCO2) level of 38 +/- 2 mmHg. Monitoring included measurement of mean arterial blood pressure (MAP), heart rate, PETCO2, SpO2 and end-tidal desflurane concentrations (FETDes). Mean blood flow velocities (Vmean) were measured in the middle cerebral artery using a bi-directional 2 MHz TCD system (EME-TC 2000 S). A first TCD measurement followed intubation (T1). Thereafter, desflurane was adjusted to 1 MAC. Six other TCDs were recorded each minute until FETDes reached the inspired fraction (T2-T7). Thereafter, CO2 reactivity was assessed with a hypocapnia test, induced by hyperventilation. Measures were done at T8 (PETCO2: 33 +/- 1 mmHg), T9 (PETCO2: 29 +/- 1 mmHg), and T10 (initial PETCO2: 38 +/- 1 mmHg). All these measurements were made before starting surgery. Analysis of variance (ANOVA) was used to analyse the data (P < 0.05 was considered as significant). RESULTS: The Vmean and heart rate increased significantly with increasing concentrations of desflurane (Vmean from 68 +/- 27 to 106 +/- 30 cm.s-1 and heart rate from 109 +/- 17 to 136 +/- 15 b.min-1 between T1 and T7). During hypocapnia, Vmean decreased to 68 +/- 23 cm.s-1 at T9, and returned to normal values with PETCO2 at 38 mmHg at T10. SpO2 remained unchanged. Mean arterial pressure was stable from T1 to T7, but decreased significantly at T9 and T10. CONCLUSION: Desflurane elicits a dose-dependent increase in cerebral blood flow velocities and heart rate, but does not change mean arterial pressure, suggesting that its cerebrovascular action is independent of its systemic vascular action. CO2 reactivity is maintained at one MAC. The results in children are similar to those seen in adults.

[Does manometric megarectum have a symptomatic role in patients complaining of dyschezia?]. / Le mégarectum manométrique a-t-il une responsabilité symptomatique chez les patients se plaignant d'une dyschésie?

UNLABELLED: Adults with dyschezia are occasionally diagnosed as having megarectum when anorectal manometry identifies rectal sensory disturbances. It remains difficult however to ascertain whether this state represents a part of the pathophysiological process responsible for symptoms, or just an associated phenomenon. The aim of this study was to highlight the symptomatic and functional features encountered in patients with dyschezia and megarectum, and to compare them with those obtained in an asymptomatic group and in a group of patients complaining of dyschezia without manometric megarectum. PATIENTS AND METHODS: The maximum tolerable volume (MTV) was defined as the highest tolerable volume which induced painful and irrepressible repletion upon inflation of the rectum with air. The upper normal range of MTV (330 mL) was obtained from rectal manometry performed in a group of 18 healthy volunteers and asymptomatic patients (mean age: 37.8 +/- 14 years, 12 F, 6 M). Between February 90 and February 92, 27 consecutive adults (48 ans +/- 15 years, 26 F, 1 M) suffering from dyschezia were found to have abnormally increased MTV, and were compared to a group of 35 patients (47 +/- 15.3 years, 34 F, 1 M) with dyschezia with MTV within normal ranges. Symptomatic patients underwent detailed interrogation, clinical examination, anorectal manometry, and evacuation proctography. RESULTS: Parity, prevalence of hysterectomy, symptoms and natural history did not differ between the two groups except for increased use of antidepressive agents in the megarectum group.(ABSTRACT TRUNCATED AT 250 WORDS)

[Thrombosis of the cerebral veins. X-ray computed tomography and MRI imaging. 11 cases]. / Thrombose des veines cérébrales. Imagerie TDM et IRM. 11 cas.

11 cases of cerebral venous thrombosis in adults are reported. Main clinical signs are: intracranial hypertension (headache, nausea, papilledema in 7 cases, loss of consciousness in 6 cases, neurological deficit in 6 cases, seizure in 4 cases. 1 patient is dead, who did not receive heparin treatment. Delay before diagnosis is between 2 and 20 days, and is shortened when arteriography or MRI are available and prescribed. At least one (or several) CT examination was performed in 10 patients. Direct signs of thrombosis are uneasily detected without contrast injection, seen here in 4 cases. Empty delta sign is observed in 7 patients, lately in 4 cases, and once only afterwards. Cerebral infarction is visualized in 7 cases over 10. Its features frequently seem evocative for cerebral venous thrombosis: triangularin 4 cases or nodular shape in 3 cases with hemorragic infarct in 7 cases, with bilateral topography in 6 cases, in frontal or central areas in 7 cases. 6 patients had a MRI examination. All cerebral infarctions appeared haemorragical, even at early stages. During subacute period, venous thrombosis is constantly and easily detected by the mean of methemoglobin high signal intensity on T1 weighted images. The prediagnosis delay is short, without necessity of arteriography. MRI should take the place of CT and arteriography in investigation of a clinically suspected cerebral venous thrombosis.

[Rare tumors of the cerebellopontine angle]. / Tumeurs rares dans l'angle ponto-cérébelleux.

Tumours of the cerebellopontine angle are essentially benign in adults, are generally treated surgically and require a preoperative assessment as precise as possible. MRI simplifies the diagnostic assessment; it is indicated as the first-line investigation and is usually sufficient whenever a tumour of the posterior cranial fossa is suspected. Acoustic neuromas represent 75% of all tumours of the cerebellopontine angle. Other tumours are rare and essentially consist of meningioma, detected in 10 to 14% of cases and cholesteatoma in 1 to 5% of cases. Cholesteatoma, with a pathognomonic appearance, must be distinguished from arachnoid cyst. Other tumours are exceptional. The authors define the diagnostic criteria based on their experience and present a recent review of the literature.

[Liver abscess. Imaging and interventional radiology in French Polynesia]. / Abcés du foie. Imagerie et radiologie interventionnelle en Polynésie Française.

23 cases of liver abscess are reported (13 pyogenous, 10 amoebic). Clinical feature is rather uniform and evocative; thanks to picture technics, diagnosis was easy in 22 cases but hesitating in one case. Semeiology revealed by scanner or echography is detailed. Both techniques are fairly equivalent considering accuracy but not really specific. The interventional radiology at the stage of diagnosis, consists in puncture (14 out of 23 cases), at the stage of therapy, in transcutaneous drainage (6/23 cases). They are performed with the assistance of scanner, echoscopy and/or radioscopy. Therapy has been medical in 13 cases/23, associated with transcutaneous drainage 6 times, surgical in 4 cases. A procedure is proposed, including early puncture to diagnose, drainage of pyogenous abscesses, only medical treatment against amoebiasis exceptionally help of surgery and controlled by echography.

[Relations between neurinoma of the VIII cranial nerve and the porus of the internal auditory meatus. Apropos of 110 cases]. / Rapports du neurinome du VIII avec le porus du conduit auditif interne (CAI). A propos de 110 cas.

110 cases of neurinomas of the VIIIth with APC extension (104 patients) were studied using MRI or CT. Classically, it is said that the tumoral mass is centered on the IAC. In our study, among 110 cases of neurinomas, only 9 were centered along the axis of IAC on axial slices and only 23 on coronal slices. The anterior development of the tumor is never more than 1 cm, except in 3 cases of large and multicystic neurinoma. We suggest that the anterior development of large tumors is limited by the VIIth nerve.

[Arterial anatomy of peroneal flaps assessed by Doppler study and arteriography]. / L'anatomie artérielle des lambeaux péroniers analysée par l'examen Doppler et l'artériographie.

Clinical applications of fasciocutaneous peroneal island flaps are important. 25 patients with cutaneous or composite defects of the lower extremity have been investigated by preoperative Doppler flowmeter and angiography. This before and after reviewed study allow the authors to establish a clinically useful peroneal arterial map which particularly concern the number and distribution of the postero-lateral septocutaneous arteries. The false positive and negative results of these two examinations are presented and explain differences with anatomic findings. Two anatomic variations are revealed by arteriography and are important for the surgical procedure. The first is the inconstant "circumflex peroneal artery" (12 cases on 22) which is the uppermost posterolateral cutaneous vessel which arises from the posterior tibial artery. The second is the angiographic view of a proximal bifurcation of the peroneal artery (9 cases). Regarding these findings, the authors classify the indications of preoperative angiography: absolute, useful, useless according to each case.

[Management of an isolated thyroid nodule or a heterogeneous nodular goiter, when thyroid scintigraphy is not available (Tahiti)]. / Conduite à tenir devant un nodule thyroïdien isolé ou au sein d'un goître multi-hétéro-nodulaire. Quand on ne dispose pas de scintigraphie thyroïdienne (Tahiti).

Thyroidal nodes (non-cystic) always put forward some difficult decision. As a matter of fact, it would not be reasonable to undergo each time a surgical operation, but it would be catastrophic to abstain wrongly. When scintigraphy and mainly cyto-puncture are feasible, so a coherent decision can be taken. When they are not possible and when only ultrasonography is available, we propose that a decision be taken according to a comprehensive approach although each argument being individually disputable.

[Diagnosis of renal, peri- and para-renal infections. Contribution of ultrasonics and x-ray computed tomography. Apropos of 10 cases]. / Diagnostic des infections rénales, péri et para-rénales. Apport de l'échographie et de la scanographie. A propos de 10 observations.

Principal signs and symptoms of renal parenchyma infections are discussed in relation to findings in 10 cases. Disorders studied were acute pyelonephritis and focal and bacterial acute nephritis, renal abscess and perinephritic phlegmon. Intravenous urography was only moderately sensitive (4/7) and of little specificity. Ultrasound imaging showed much greater sensitivity (8/10), undetected lesions being the earliest cases of severe acute pyelonephritis. The scanner was the most sensitive investigatory method since it associated anatomical and functional aspects in data obtained, justifying its initial use for certain authors.

[X-ray computed tomographic detection of foraminal neurinoma. Apropos of a case]. / Dépistage scanographique du neurinome foraminal. A propos d'un cas.

About the case of the vertebral neurilemmoma diagnosed at the very beginning, purely inside the foramen, precursor of the classical "hourglass Tumor", the authors remain the clinical evolution and the anatomy of the intervertebral foramen's neurilemmoma. They insist on the insufficiency of the conventional radiology in early diagnosis. They also exposed the C.T. technic and his results; the neurilemmoma can be diagnosed before his extension over the limits of the intervertebral foramen, but only if a precis neurological level is known.

Pneumopericardium: an unusual complication of endotracheal laser surgery.

The case report is presented of a patient with a left upper lobe tumour of the lung in whom use of laser photocoagulation induced a pneumopericardium. The possible causes of the complication are considered.

[Comparative study of computed x-ray tomography and saccoradiculography in the diagnosis of early lumbar disk herniation. Apropos of 50 surgically-proven cases]. / Etude comparative du scanner et de la saccoradiculographie dans le diagnostic des hernies discales lombaires inaugurales. A propos de 50 cas vérifiés chirurgicalement.

Comparison of diagnostic accuracy using the two methods showed scanner imaging to provide superior results, with confirmation of herniated disc in 90 p. 100 cases based on purely discal semiological features. Limitations of the method result from the absence of epidural fat (narrow lumbar canals). A new hierarchy of radiological explorations in resistant lumbosciatica is proposed.

Mechanical ventilation with superimposed high frequency oscillation in the normal rat.

The gas exchange efficacy of high frequency oscillations superimposed on conventional mechanical ventilation (CMV-HFO) was assessed in 24 normal rats. These animals were anesthetized, paralyzed, tracheotomized and placed in a body box in order to measure the magnitude of the CMV tidal volume and that of the superimposed oscillations. The frequency of oscillations was 20 Hz and the mechanical ventilator delivered a tidal volume of 5 ml/kg at a rate of 50 min-1 which corresponded to a slight alveolar hypoventilation. Four groups of animals were studied with two magnitudes of oscillation (0.75 and 1.25 ml/kg) and with two different volumes of instrumental dead space. Blood gases were measured during CMV-HFO and during CMV alone from blood samples taken from a carotid artery. There were no significant differences in arterial PCO2 during these two modes of ventilation except a decrease in the group with large amplitude oscillations and a small dead space in which the oscillations alone could ensure quasi-normal gas exchange. By contrast in 20 out of 24 animals there was a decrease of alveolar - arterial oxygen difference with CMV-HFO even in the case of small oscillations and a large dead space. These results suggest that VA/Q homogeneity is improved by interregional and/or intraregional redistribution of ventilation due to the high frequency oscillations superimposed on conventional mechanical ventilation.