Sexual assault and MDMA: the distinction between consciousness and awareness when it comes to consent.

In France, the term chemical or drug-assisted submission is usually defined as the rendering of a person vulnerable by the surreptitious administration of an active substance with the purpose of prejudicing the person or his/her possessions. If the harm is sexual assault, establishing the victim's submission involves both proving that a dangerous substance was administered, providing material evidence of the infraction (the assault), i.e. the detection of traces in a physical examination and samples, and proving the absence of consent. We report the case of a woman who was sexually assaulted after having been surreptitiously administered methylenedioxymethamphetamine. In this special case, the woman remained in a state of vigilance (conscious) throughout, so there is doubt about whether or not she consented. In other words, the ability to consent is debatable.

Transverse arch hypoplasia predisposes to aneurysm formation at the repair site after patch angioplasty for coarctation of the aorta.

OBJECTIVES: This study used magnetic resonance imaging (MRI) to evaluate the morphology and pathophysiology of aneurysm formation after patch angioplasty for coarctation of the aorta. BACKGROUND: Late aneurysm formation at the repair site is a well known and frequent complication after patch angioplasty. However, because the underlying mechanisms remain unresolved, postoperative outcome is unpredictable and adequate follow-up difficult. METHODS: Seventy-three of 85 patients with patch angioplasty for coarctation of the aorta were screened for aneurysm formation. Magnetic resonance imaging was performed in all 33 patients with an aneurysm, and results were compared with those for 13 control patients and 10 normal subjects. Mean (+/- SD) time between operation and MRI was 12.0 +/- 2.0 years. Aneurysm was defined as the ratio of the diameter of the aorta at the repair site to the diaphragmatic aorta > or = 1.5. Hypoplasia of the transverse arch and recoarctation at the repair site were defined as a ratio < 0.9. Transverse arch ratios on MRI were compared with those on preoperative cineangiography and the pressure gradient between the patient's right and left arm. RESULTS: All 33 patients with an aneurysm had a hypoplastic transverse arch. The 13 patients with a normal ratio at the repair site had a normal transverse arch ratio (chi square, p < 0.0001). Logarithmic regression showed a significant negative correlation (r = 0.62) between the repair site and transverse arch ratios. A significant pressure difference between the patient's right and left arm was found in patients with versus those without aneurysm (p = 0.0009). No significant difference was found between transverse arch ratios on preoperative cineangiography and postoperative MRI (mean 0.014 +/- 0.1, p = 0.4). CONCLUSIONS: Aneurysm formation at the repair site is highly related to hypoplasia of the transverse arch. Sufficient catch-up growth of a hypoplastic transverse arch is rare after late patch angioplasty. Dynamic phenomena, such as flow acceleration and turbulence, originating in a narrow transverse arch, may contribute to aneurysm formation at the repair site after patch angioplasty.

Value of computed tomography as outcome predictor of supraglottic squamous cell carcinoma treated by definitive radiation therapy.

PURPOSE: To investigate the value of several CT-derived tumor parameters as predictors of local outcome of supraglottic squamous cell carcinoma treated by definitive radiation therapy. METHODS AND MATERIALS: The pretreatment CT studies of 103 patients with supraglottic squamous cell carcinoma were reviewed for tumoral involvement of specific laryngeal anatomic subsites and extralaryngeal tumor spread. After redigitizing the films, tumor volume was calculated with the summation-of-areas technique. Mean follow-up time was 3.4 years. Actuarial statistical analysis of local and locoregional outcome was done for each of the covariates; multivariate analysis was performed using Cox's proportional hazards model. RESULTS: In the actuarial analysis CT-determined primary tumor volume was significantly correlated with local recurrence rate (p < 0.001). Degree of involvement of the paraglottic space at the level of the true vocal cord (p < 0.05) and subglottic extension (p < 0.001) were also significantly correlated with local recurrence rate. In the multivariate analysis, only degree of involvement of the preepiglottic space (p < 0.01) and subglottic extension (p < 0.01) were found to be independent predictors of local recurrence. Total tumor volume was the strongest independent predictor of locoregional failure (p < 0.01). CONCLUSIONS: CT-determined tumor parameters are strong predictors of local and locoregional outcome of supraglottic carcinoma treated by definitive irradiation.

Laryngeal tumor volume measurements determined with CT: a study on intra- and interobserver variability.

PURPOSE: To investigate the intra- and interobserver variability of computed tomography-based volume measurements of laryngeal tumors. METHODS AND MATERIALS: The volume of 13 laryngeal tumors was repeatedly measured by five independent observers in four different sessions, using the summation-of-areas technique. Mean tumor volume and its standard deviation were calculated for each tumor. Statistical analysis was done with analysis of variance, Spearman rank correlation, and linear regression. RESULTS: Both the effect of the observers (p < 0.0001) and the effect of the session (p < 0.01) on tumor volume was statistically significant. Interobserver variability was the most important component of total variability (89.3%). A significant rank correlation was found between mean volume and standard deviation (p < 0.01); the relationship between mean tumor volume and standard deviation can be described using linear regression [standard deviation = 0.28 volume + 0.35 (R = 0.79)]. CONCLUSION: Total variability in the computed tomography-based measurement of laryngeal tumor volume can be reduced by having the measurements done by a single trained observer.

Predicting the local outcome of glottic squamous cell carcinoma after definitive radiation therapy: value of computed tomography-determined tumour parameters.

BACKGROUND AND PURPOSE: The T-classification has shortcomings in the prediction of local outcome of glottic squamous cell carcinoma (SCC) treated by definitive radiation therapy. In this regard, the value of several CT-derived tumour parameters as predictors of local outcome was investigated. MATERIALS AND METHODS: The pretreatment CT studies of 119 patients with glottic SCC (T1, n=61; T2, n=40; T3, n=14; T4, n=4) treated with curative intent by radiation therapy were reviewed for tumoral involvement of specific laryngeal anatomic subsites (including laryngeal cartilages). Tumour volume was calculated with the summation-of-areas technique. Actuarial (life-table) statistical analysis was done for each of the covariates; multivariate analysis was performed using the Cox proportional hazards model. RESULTS: In the actuarial analysis tumour volume was significantly correlated with local recurrence rate (P=0.0062). Involvement of the cricoid cartilage (P=0.0052), anterior commissure (P=0.0203), subglottis (P=0.0481) and preepiglottic space (P=0.0134) and degree of involvement of the true vocal cord (P=0.0441) and paraglottic space at the level of the true vocal cord (P=0.0002) were also significantly correlated with local recurrence rate. In the multivariate analysis, only degree of involvement of the paraglottic space (at the level of the true vocal cord) (P=0.0001) and preepiglottic space (P=0.02) were found to be independent predictors of local recurrence. The T-category was significantly correlated with local outcome in the actuarial analysis (P=0.0001), but not in the multivariate analysis (P=0.5915). CONCLUSIONS: Several CT-derived parameters are powerful predictors of local outcome in glottic cancer treated with radiation therapy; some of these parameters are stronger linked to the local control rate than the T-classification.

Non-invasive tumour perfusion measurement by dynamic CT: preliminary results.

In 18 patients the perfusion of a malignant head and neck tumour was estimated using contrast enhanced dynamic computed tomography. The mean estimated perfusion was 75.5 ml/100 g/min, varying between 27.9 and 131.9. Eleven patients were treated with radiation therapy; the obtained perfusion rates were significantly different between tumours with a favourable and those with an unfavourable early outcome.

Experimental study of the pharmacokinetics and dose response of ferrite particles used as a contrast agent in MRI of the normal liver of the rabbit.

Superparamagnetic ferrite is a specific magnetic resonance imaging (MRI) contrast agent for the liver and the spleen. The large electronic magnetic moments of the ferrite particles create local field inhomogeneities that shorten the transversal relaxation time and reduce the spin-echo amplitude and the intensity of the liver and spleen signals in MR images. MRI was performed at 1.5 T using a SE sequence with TR/TE = 300/15 milliseconds. Pharmacokinetics were studied on five rabbits during five hours and up to 11 days after ferrite injection with doses ranging from 0.2 to 1 mg Fe/kg. Dose responses (0.2 mg to 8 mg Fe/kg) were studied on 11 additional rabbits, at three hours and three days after injection. Results show that the effect of ferrite on the liver images is stable between 30 minutes and 6 hours, and that the liver images recover their intensities before injection after about two days. The liver intensity drops to half its value for a dose of 1.25 mg Fe/kg (for TR/TE = 300/15 milliseconds). Our results support the conclusions from studies on other animal species that ferrite should be considered a useful MRI contrast agent for clinical investigations of the liver.

Intravenous ionic contrast media cause local prostacyclin release in man.

The effect of intravenous administration of ionic contrast media on local release of prostacyclin (PGI2) was investigated in man. Iodamide and ioxaglate, high- and low-osmolality contrast media, respectively, both significantly increased PGI2 levels at the site of injection. Iodamide was the most active, whereas an identical volume of isotonic saline had no effect. This study suggests that local formation of PGI2 may adequately reflect the degree of endothelial irritation that is caused by contrast media and that depends in part on their osmolality.

Magnetic resonance imaging-histomorphologic correlation studies on paramagnetic metalloporphyrins in rat models of necrosis.

RATIONALE AND OBJECTIVES: The authors intended to confirm previous findings that paramagnetic porphyrins are avid only for intratumoral nonviable tissues, but not for viable tumor cells, and to test the hypothesis that necrosis, regardless of location and origin, can be visualized by metalloporphyrin enhanced magnetic resonance imaging (MRI). METHODS: Intravenous administrations of gadolinium mesoporphyrin (Gd-MP), manganese tetraphenylporphyrin (Mn-TPP), manganese methylpyrroporphyrin-gadopentetate dimeglumine complex (Mn-MPP-Gd) and manganese tetra(4-sulfonatophenyl)porphyrin (MnTPPS4) at 0.05 mmol/kg were compared with those of gadopentetate dimeglumine (Gd-DTPA) at 0.1 mmol/kg in 38 rats with cholestatic liver necrosis, alcohol- and laser-induced coagulation necrosis in liver, and skeletal muscle, reperfused hepatic infarction, and segmental renal infarction. T1-weighted spin echo MRI (TR/TE = 300/15 mseconds) was acquired before and as long as 48 hours after injection, matched with histologic findings, and correlated with Gd/ Mn tissue content measurements. RESULTS: Both Gd-DTPA and the four metalloporphyrins initially caused a similar nonspecific negative contrast enhancement in the necrosis. However, a strong and persisting positive enhancement (necrosis-to-normal contrast ratio ranging from 1.5 to 2.0) developed only with metalloporphyrins in all types of necrosis. In liver and kidney, Gd and Mn concentrations at 24 hours were comparable in necrotic and normal tissues. In muscle, the concentrations were more than eight times higher in necrotic than in normal tissue. CONCLUSIONS: The implied affinity of metalloporphyrins for necrosis with presumably increased relaxivity suggests a possible mode of targetability for MRI contrast media that may elicit novel applications.

Metastatic calcification within bone. The main cause of osteosclerosis in hypervitaminosis D3. Radiologic-pathologic correlation.

Because the pathogenesis of osteosclerosis in hypervitaminosis D is still not well elucidated, the authors experimentally studied hypervitaminosis D3 in 66 rabbits by injecting different doses of vitamin D3. Contact radiographs of bone specimens showed various signs of osteosclerosis, including dense epiphyses and metaphyses, thickened bony articular surfaces, dense metaphyseal bands, modeling defects at the metaphysis, and dense and thickened cortical bone. The corresponding pathologic sections showed that conspicuous metastatic calcification coated the trabeculae and filled bone marrow cavity and caverns in the original but porotic cortical and periosteal new bone. Rather than being resorbed, the metastatic calcifications were embedded in a thick layer of newly formed bone 6 to 14 weeks after vitamin D3 withdrawal. This study suggests that in hypervitaminosis D3, the osteoblasts and bone marrow undergo degeneration, leading to necrosis and calcification. After vitamin D3 withdrawal, osteoblasts reappear and become overactive, leading to overossification.

Bone remodeling in hypervitaminosis D3. Radiologic-microangiographic-pathologic correlations.

To investigate the mechanism of bone changes in hypervitaminosis D3, we compared contact radiographs, microangiograms by injection of Chinese ink, and corresponding histopathologic macrosections of 66 rabbits that received different doses of vitamin D3. In early stages, radiographs showed subperiosteal bone resorption and porotic cortical bone. The corresponding microangiograms showed proliferating vessels in the periosteum and cortical bone with associated dilatation of the Haversian and Volkmann's canals. When metastatic calcification fills these intracortical caverns or the intertrabecular spaces in the metaphysis and physis, the bone shows a diffuse increased density on radiographs. A dense band in the metaphysis reflects a thickening of calcified chondromatrix due to a hypotrophy of the distal metaphyseal capillaries. Six to 12 weeks after vitamin D3 withdrawal, radiographs showed further increased density of the cortical bone, due to newly formed bone and metastatic calcification. Alternating bands of increased and decreased density in the metaphysis and physis reflect the reinvasion of normal vasculature between growth cartilage and calcified chondromatrix, with normalization of endochondral ossification.

Magnetic resonance imaging, microangiography, and histology in a rat model of primary liver cancer.

RATIONALE AND OBJECTIVES: N-nitrosodiethylamine is able to induce various benign and malignant liver lesions in rats with a high success rate and a low mortality rate. It provides a more appropriate model that better simulates the various lesions occurring in patients than the usual model of tumor implantations. METHODS: Hepatic carcinogenesis was induced in 58 Wistar rats using oral N-nitrosodiethylamine. The rats subsequently were studied by liver magnetic resonance imaging (MRI), postmortem microangiography, and histologic examination. RESULTS: Hepatic tumors developed in 57 rats. A wide variety of the tumors in the degree of vascularization, the type of vessels, the areas of intratumoral secretion and necrosis, and the tumor cell differentiation resulted from the tumor model. The authors were able to assess the contribution of the vascular, extravascular, and cellular components in the final pattern of contrast enhancement in MRI. CONCLUSIONS: The N-nitrosoethylamine model for hepatic tumor induction is simple, and provides a more representative range of tumors for experimental evaluation.

The uptake of manganese dipyridoxal-diphosphate by chemically induced hepatocellular carcinoma in rats. A correlation between contrast-media-enhanced magnetic resonance imaging, tumor differentiation, and vascularization.

OBJECTIVES AND RATIONALE: Negative enhancement of implanted liver tumors has been achieved in preclinical studies on manganese dipyridoxal-diphosphate (Mn-DPDP), a new hepatobiliary specific contrast agent for magnetic resonance imaging (MRI). The authors investigated the effects of Mn-DPDP on primary liver cancer and its possible mechanisms. METHODS: Magnetic resonance imaging was performed in 15 rats with chemically induced hepatocellular carcinoma (HCC) before and after Mn-DPDP injection. Both tumor-liver contrast-to-noise ratio and absolute tumor enhancement were evaluated and compared with the MRI results of a nonspecific contrast agent, gadolinium-DOTA, and correlated with corresponding microangiographic and histologic findings. RESULTS: Mn-DPDP injection led to a persistent positive enhancement in differentiated solid HCCs (22/23) with maximal conspicuity at 24 hours. Undifferentiated HCCs were all delineated by a prompt negative enhancement (20/20) with maximal conspicuity within 30 minutes.

Blood pressure during long-term converting-enzyme inhibition predicts the curability of renovascular hypertension by angioplasty.

Percutaneous transluminal renal angioplasty (PTRA) was performed in 28 hypertensive patients with 50% or more unilateral renal artery stenosis. Prospectively, the study compared the extent to which systolic (SBP) and diastolic (DBP) pressure during long-term converting-enzyme inhibition (CEI) and the ipsi- to contralateral renal vein renin ratio (RVR) predicted success of PTRA, defined as SBP less than 160 mmHg and DBP less than 95 mmHg. Both SBP and DBP after PTRA were positively correlated with pressure during CEI (P less than 0.001) and negatively with RVR (P less than 0.03). In multiple regression these associations were independent and remained statistically significant. In discriminant analysis, a SBP during CEI less than 160 mmHg, a DBP during CEI less than 95 mmHg, and a RVR greater than or equal to 1.5 identified with equal accuracy the success of PTRA. Furthermore, in patients with a SBP during CEI less than 160 mmHg, the demonstration of a RVR greater than or equal to 1.5 increased (P less than 0.05) the prediction of a positive outcome from 50 to 67%. In contrast, in 92% of the patients with a SBP during CEI greater than 160 mmHg, PTRA was not successful. Thus, blood pressure measurements during long-term CEI predict the curability by PTRA of renovascular hypertension and can be employed either alone or in association with the RVR.

MR of cerebellar cortical dysplasia.

MR imaging findings are described in four patients with cerebellar cortical dysplasia. Typically, cerebellar disorganized folia were seen as an irregular bumpy gray-white matter interface. In addition, cystlike cortical abnormalities were observed in two patients and associated supratentorial developmental abnormalities were seen in three patients. To our knowledge, cerebellar cortical dysplasia without supratentorial abnormalities, as seen in one patient, has not been reported before. We suggest that cerebellar cortical dysplasia represents a spectrum of abnormalities ranging from mild to extensive in severity.

Lyme disease in childhood presenting as primary leptomeningeal enhancement without parenchymal findings on MR.

We report the MR appearance of a rare case of Lyme disease presenting as diffuse leptomeningeal enhancement in the absence of parenchymal lesions. In the appropriate clinical setting, one should consider Lyme disease in the differential diagnosis of meningeal enhancement.

Simultaneous occurrence of developmental venous anomalies and cavernous angiomas.

PURPOSE: To study the clinical and radiologic findings in 15 patients presenting with both developmental venous anomalies and cavernous angiomas and to determine which lesions caused the acute clinical symptoms. METHODS: Lesions were infratentorial in 7 patients and supratentorial in 7 other patients. In one patient the developmental venous anomaly was infratentorial and the cavernous angioma supratentorial. In all 15 patients clinical examination and CT were performed. In 10 patients MR was performed at the time of the initial CT scan. In 5 patients only late MR is available. RESULTS: Acute clinical signs were present in 9 patients (epilepsy, hemiplegia, meningeal signs, cranial nerve deficit). On CT the cavernous angioma was missed in 9 patients, in 6 patients because of acute hemorrhage. On MR the cavernous angioma was missed in 1 of 2 cases with acute hemorrhage but seen in all other patients. On repeat MR all cavernous angiomas were correctly identified. On CT, 11 developmental venous anomalies were seen. On MR all developmental venous anomalies were seen. CONCLUSIONS: The frequent association of developmental venous anomalies and cavernous angiomas is confirmed. MR is superior to CT in the detection of both cavernous angiomas and developmental venous anomalies. Furthermore our data support the hypothesis that cavernous angiomas and not the developmental venous anomalies cause the acute clinical symptoms because of hemorrhage.

Orbital fat edema in anorexia nervosa: a reversible finding.

Orbital fat edema was found in a patient with long-standing severe anorexia nervosa. The changes disappeared after the patient gained weight. The underlying mechanisms remains unexplained, but the changes most likely coincide with the disappearance of fat tissue and the appearance of edema following disturbance of the electrolyte/fluid balance.

Prominent dural enhancement adjacent to nonmeningiomatous malignant lesions on contrast-enhanced MR images.

Prominent dural enhancement was noted in 10 (16%) of 61 superficial malignant intracranial tumors studied with contrast-enhanced MR imaging during a 2-year period. Included were six glioblastomas, three parenchymal metastases, and one case of dural metastasis. Seven patients had surgery. In four, there was extensive leptomeningeal invasion in the center of the lesion. In two of these lesions there was firm attachment of the center of the tumor to the dura, but without dural invasion despite extensive external carotid artery supply to the tumor in one case. In two cases the overlying dura was normal, and there was no leptomeningeal tumoral invasion. In the case of dural metastasis, huge nodular lesions were present along the inner aspect of the dura. In none of the cases did prominent dural enhancement adjacent to the tumor correspond with tumoral invasion or extension to the dura. Prominent dural enhancement on contrast-enhanced MR images appears to be much less frequent in malignant tumor than in meningioma, where it is seen in up to 60% of the cases. We believe this finding is more likely to represent reactive changes of the dura than tumoral invasion.

Comparison between Gd-DTPA, Gd-EOB-DTPA, and Mn-DPDP in induced HCC in rats: a correlation study of MR imaging, microangiography, and histology.

The behaviour of two liver-specific contrast MR agents, Gd-EOB-DTPA and Mn-DPDP and one nonspecific contrast agent, Gd-DTPA, was compared in a rat model of chemically induced hepatocellular carcinoma (HCC). The study included contrast enhanced MR imaging and the corresponding microangiography and histology. Analysis of the MR images showed similar degrees of maximum relative liver enhancement: 47.5 +/- 8.2% for Gd-EOB-DTPA (0.03 mmol/kg) at 5 min postinjection and 52.5 +/- 14.4% for Mn-DPDP (0.025 mmol/kg) at 15 min; both exceeded the value obtained with Gd-DTPA (34.8 +/- 13.6%, at 5 min), even at 0.3 mmol/kg. Gd-EOB-DTPA caused a similar "negative" enhancement of all types of HCC, independent of their differentiation and vascularization, i.e., lesion-to-liver contrast-to-noise ratio (CNR) of differentiated and undifferentiated HCC increased negatively from, respectively, 1.9 +/- 1.1 and -5.1 +/- 3.1 before contrast to -5.2 +/- 2.4 and -11.8 +/- 4.8 at 5 min after contrast. On Mn-DPDP enhanced images, the undifferentiated HCCs showed up negatively (CNR -5.5 +/- 4.7 before contrast to -13.7 +/- 10 at 15 min after contrast), whereas the more differentiated tumors showed up positively (CNR from 2.3 +/- 2.0 before contrast to 12.5 +/- 3.5 at 24 hr postcontrast) due to active uptake and delayed elimination of Mn-DPDP.