Biophysical properties of the normal-sized aorta in patients with Marfan syndrome: evaluation with MR flow mapping.

PURPOSE: To investigate the feasibility of magnetic resonance (MR) flow mapping in the assessment of aortic biophysical properties in patients with Marfan syndrome and to detect differences in biophysical properties in the normal-sized aorta distal to the aortic root between these patients and matched control subjects. MATERIALS AND METHODS: Seventy-eight patients with Marfan syndrome with aortic root dilatation and 23 matched control subjects underwent MR flow mapping in four locations in the normal-sized aorta (1, ascending aorta; 2, thoracic descending aorta; 3, descending aorta at the level of the diaphragm; and 4, abdominal descending aorta). Distensibility at each location and flow wave velocity between locations were calculated. RESULTS: Compared with the control subjects, patients with Marfan syndrome had decreased aortic distensibility at three of the four locations (levels 1, 2, and 4; P <.05) and increased flow wave velocity between all locations (P <.05) in the aorta. In patients with Marfan syndrome, flow wave velocity was also significantly increased along the entire aortic tract beyond the aortic root (from level 1 to level 4). CONCLUSION: MR imaging reveals abnormal biophysical properties of the normal-sized aorta in patients with Marfan syndrome. Monitoring of these properties is relevant for evaluating disease progression and treatment options.

Determinants of quantitative spectral electroencephalography in early Alzheimer's disease: cognitive function, regional cerebral blood flow, and computed tomography.

Electroencephalography (EEG) bands may have different clinical or physiological correlates at initial diagnosis of Alzheimer's disease (AD). We studied 163 consecutive patients with probable (n = 105) and possible (n = 58) AD with measurements of cognitive function (CAMCOG), regional cerebral blood flow (rCBF) with single photon emission computed tomography using technetium-99m-labeled hexamethylpropylene amine oxime, and computed tomography (CT). Lower CAMCOG scores were significantly and most strongly associated with lower parieto-occipital and fronto-central alpha power. In a separate analysis of cognitive domains, disturbances in language, praxis, attention, and abstraction were also significantly and most consistently related to decrease in alpha power. Presence of cortical atrophy as measured on CT showed some statistically significant relations with EEG bands, but these associations were not consistent. Lower temporal and parietal rCBF were significantly related to lower parieto-occipital alpha activity. Presence of leukoaraiosis was significantly associated with lower beta values, but also with higher absolute theta and delta activity. The results suggest that alpha on EEG is most closely linked to cognitive function and rCBF, while beta and theta activity more likely reflect lower cortical or subcortical changes. Our study thus provides evidence that the EEG bands reflect differential pathophysiologic changes in AD.

MR angiography as a screening tool for intracranial aneurysms: feasibility, test characteristics, and interobserver agreement.

OBJECTIVE: MR angiography may be an appropriate tool to screen for unruptured intracranial aneurysms. Feasibility, test characteristics, and interobserver agreement in evaluation of MR angiograms were assessed by members of the MARS (Magnetic resonance Angiography in Relatives of patients with Subarachnoid hemorrhage) Study Group. SUBJECTS AND METHODS: We screened 626 first-degree relatives of a consecutive series of 193 patients with subarachnoid hemorrhage examined at two institutions. We used MR imaging and MR angiography (three-dimensional time-of-flight imaging at both institutions and additional three-dimensional phase-contrast imaging at one institution). Three observers independently assessed the MR angiograms. Conventional angiography was performed in relatives with possible or definite aneurysms on MR angiography and was considered the standard of reference. RESULTS: Thirty-three aneurysms were found in 25 (4%; 95% confidence interval [CI], 3-6%) of 626 relatives. Thirteen (8%) of 169 relatives who refused screening had MR-related reasons; an additional six persons could not be screened because of contraindications for MR imaging (pregnancy, n = 1; claustrophobia, n = 5). The positive predictive value of MR angiography was 100% (95% CI, 79-100%) for "definite" aneurysms and 58% (95% CI, 28-85%) for "possible" aneurysms. Sensitivity of MR angiography was estimated at 83% (95% CI, 65-94%) and specificity at 97% (95% CI, 94-98%). Interobserver agreement in the evaluation of MR angiograms was poor (kappa < .30), probably because different diagnostic strategies used by individual observers resulted in different use of the assessment category "possible aneurysm." CONCLUSION: MR angiography is a feasible screening tool for detection of intracranial aneurysms. Positive predictive value, sensitivity, and specificity are acceptable when at least two neuroradiologists independently assess MR angiograms.

Petrosal bone: coronal reconstructions from axial spiral CT data obtained with 0.5-mm collimation can replace direct coronal sequential CT scans.

PURPOSE: To investigate whether coronal multiplanar reconstruction (MPR) images of the petrosal bone from axial spiral computed tomographic (CT) data obtained with 0.5-mm collimation can replace direct coronal sequential CT scans obtained with 0.5- or 1.0-mm collimation. MATERIALS AND METHODS: The differences in diagnostic quality between thin-section coronal sequential CT scans of 24 petrosal bones in 12 patients and matched MPR images were assessed by five observers. The matched MPR images were calculated with both trilinear and tricubic interpolation. Image resolution was determined by measuring the three-dimensional point spread function. RESULTS: All observers preferred tricubically interpolated MPR images over trilinearly interpolated images. Subjective differences in image quality between direct coronal scans and matched tricubically interpolated MPR images were small. Only the direct coronal scans with the highest image quality (0.5-mm collimation, 465 mAs) were judged to be slightly better than the matched MPR images. With regard to direct coronal scans obtained at 245 mAs and/or 1.0-mm collimation, either there was no preference or the MPR images were preferred. CONCLUSION: Coronal MPR images from axial spiral CT obtained with 0.5-mm collimation can replace direct coronal sequential CT scans.

Progression of abnormalities in adrenomyeloneuropathy and neurologically asymptomatic X-linked adrenoleukodystrophy despite treatment with "Lorenzo's oil".

OBJECTIVES: X-linked adrenoleukodystrophy (X-ALD) is an inherited disorder of peroxisomal fatty acid oxidation, biochemically characterised by the accumulation of saturated very long chain fatty acids (VLCFAs), particularly hexacosanoic acid (C26:0). Dietary treatment with a 4:1 mixture of glyceroltrioleate and glyceroltrierucate ("Lorenzo's oil") normalises plasma VLCFA concentrations, but neither ameliorates nor arrests the rapid progression of neurological symptoms in the cerebral variants of X-ALD. The efficacy of "Lorenzo's oil" in the milder phenotypes of X-ALD was assessed, as this has been much less investigated. METHODS: Twenty two patients who were treated with "Lorenzo's oil" for at least 12 months for a median period of 2.5 (range 1.0-6.0) years were studied. Two had asymptomatic ALD, four the "Addison only" variant, 13 adrenomyeloneuropathy (AMN), and three were symptomatic female carriers. RESULTS: The plasma C26:0 concentration normalised or near normalised in 19 patients (86%), in the three others it decreased significantly. Nevertheless, disability as measured with the extended disability status scale score increased mildly (0.5 (95% confidence interval (95% CI) 0.25-1.0)) in the 16 patients with neurological symptoms. Furthermore, one "Addison only" patient and one patient with AMN developed cerebral demyelination, and another "Addison only" patient developed AMN. Adrenocortical insufficiency evolved in one patient with AMN, and hypogonadism in one patient with asymptomatic ALD and two patients with AMN. Nerve conduction, evoked potential studies (SEP, BAEP, VEP), and abnormalities on cerebral MRI did not improve. On the other hand, side effects were often noted-namely, mild increases in liver enzymes (55%), thrombocytopenia (55%), gastrointestinal complaints (14%), and gingivitis (14%). We also found a mild decrease in haemoglobin concentration and leucocyte count. CONCLUSIONS: The data suggest that treatment with "Lorenzo's oil" neither improved neurological or endocrine function nor arrested progression of the disease. Furthermore, the oil often induced adverse effects. Therefore, it is advocated that "Lorenzo's oil" should not be prescribed routinely to patients with X-ALD who already have neurological deficits.

A 100-year-old anatomical specimen presenting with boomerang-like skeletal dysplasia: diagnostic strategies and outcome.

The Museum Vrolik collection of human anatomy comprises 360 recently redescribed specimens with congenital anomalies. The specimen described here dated from 1881 and presented with a general embryonic appearance, disproportionate short stature, brachycephaly, widened cranial sutures, hypertelorism, microphthalmia, bilateral cleft lip and palate, micrognathia, short and curved limbs, polysyndactyly, and abnormal female genitalia. Conventional radiography was hampered by decalcification of the skeleton, due to acidification of the preservation fluid. The use of additional imaging techniques, i.e., mammography, computerized tomography with three-dimensional reconstruction, and magnetic resonance imaging eventually led us to conclude that the condition of our specimen was similar to Piepkorn type skeletal dysplasia, boomerang dysplasia, and a condition described by Carpenter and Hunter [1982: J Med Genet 19:311-315], though none of these diagnoses seemed fully applicable.

Measurement of temporal regional cerebral perfusion with single-photon emission tomography predicts rate of decline in language function and survival in early Alzheimer's disease.

We determined the relationship between regional cerebral blood flow (rCBF) measured with single-photon emission tomography (SPET) and decline in cognitive function and survival in Alzheimer's disease. In a prospective follow-up study, 69 consecutively referred patients with early probable Alzheimer's disease (NINCDS/ADRDA criteria) underwent SPET performed at the time of initial diagnosis using technetium-99m-labelled hexamethylpropylene amine oxime. Neuropsychological function was assessed at baseline and after 6 months and survival data were available on all patients, extending to 5.5 years of follow-up. Lower left temporal (P<0.01) and lower left parietal (P<0.01) rCBF were statistically significantly related to decline in language function after 6 months. The association between left temporal rCBF and survival was also statistically significant (P<0.05) using Cox proportional hazards regression analysis. Performing analysis with quartiles of the distribution, we found a threshold effect for low left temporal rCBF (rCBF<73.7%, P<0. 01) and high risk of mortality. In this lowest quartile, median survival time was 2.7 years (follow-up to 5.2 years), compared with 4.4 years in the other quartiles (follow-up to 5.5 years). Kaplan-Meier survival curves showed statistically significant (P<0. 05, log rank test) survival curves for the lowest versus other quartiles of left temporal rCBF. All results were unaffected by adjustment for age, sex, dementia severity, duration of symptoms, education and ratings of local cortical atrophy. We conclude that left temporal rCBF predicts decline in language function and survival in patients with early probable Alzheimer's disease, with a threshold effect of low rCBF and high risk of mortality.

Symptoms and signs related to the trigeminal nerve: diagnostic yield of MR imaging.

PURPOSE: To assess the diagnostic yield of magnetic resonance (MR) imaging in patients with symptoms and signs related to the trigeminal nerve. MATERIALS AND METHODS: Medical records and MR imaging studies in 112 consecutive patients referred for MR imaging over 5 years were evaluated. MR images were independently reviewed by two neuroradiologists unaware of the clinical findings. Signs and symptoms at presentation were associated with either a positive or negative MR imaging outcome. Logistic regression analysis was performed to identify clinical variables related to imaging results. RESULTS: Sixty-eight (61%) patients had positive MR imaging findings related to symptoms and signs. Trigeminal neuralgia was correlated with a negative MR imaging outcome (P < .001). Numbness (P < .01), impaired sensation (P < .001), other neurologic symptoms and signs (P < .01), progression of symptoms and signs (P < .001), and duration of symptoms of less than 1 year (P < .001) corresponded to a positive MR imaging outcome. Two regression models, each with three clinical parameters (progression, duration < 1 year, and trigeminal neuralgia or impaired sensation), had comparable accuracy for prediction of the MR imaging outcome. CONCLUSION: Clinical findings can be used to identify groups in which a high or a low yield of MR imaging is correlated with symptoms and signs related to the trigeminal nerve.

Congenital anomalies in the teratological collection of Museum Vrolik in Amsterdam, The Netherlands. III: primary field defects, sequences, and other complex anomalies.

The Museum Vrolik collection of the Department of Anatomy and Embryology of the Academic Medical Center, University of Amsterdam, founded by Gerardus Vrolik (1775-1859) and his son Willem Vrolik (1801-1863), consists of more than 5,000 specimens of human and animal anatomy, embryology, pathology, and congenital anomalies. Recently, the collection of congenital anomalies, comprising 360 specimens, was recatalogued and redescribed according to contemporary morphogenetic views. The original descriptions, if preserved, were compared with the clinical, radiographical, and magnetic resonance imaging findings. In 120 specimens the following midline anomalies, primary field defects, and sequences were diagnosed: holoprosencephaly sequence; aprosencephaly/atelencephaly; cleft lip; Pierre Robin sequence; omphalocele; diaphragmatic hernia; ectopic heart; bladder exstrophy; cloacal exstrophy; caudal dysgenesis; prune belly sequence; sirenomelia; fetal akinesia sequence; and disruption sequences. Polytopic field defects and associations were diagnosed in 25 specimens. We discuss the opinions of Gerardus and Willem Vrolik, who tried to find reasonable explanations for the dysmorphogenetic entities they investigated, rather than accepting the traditional superstitions.

Congenital anomalies in the teratological collection of Museum Vrolik in Amsterdam, The Netherlands. V: conjoined and acardiac twins.

The Museum Vrolik collection of the Department of Anatomy and Embryology of the Academic Medical Center, University of Amsterdam, founded by Gerardus Vrolik (1775-1859) and his son Willem Vrolik (1801-1863), consists of more than 5,000 specimens of human and animal anatomy, embryology, pathology, and congenital anomalies. Recently, the collection of congenital anomalies, comprising 360 specimens, was recatalogued and redescribed according to contemporary perspectives. The original descriptions, as far as preserved, were compared with the clinical, radiographic, and magnetic resonance imaging findings. We diagnosed 30 symmetrical conjoined twins (CTs), 11 parasitic CTs, and 16 acardiac twins. Within the group of symmetrical CTs, the following concomitant external anomalies were found in 15 specimens: neural tube defects, holoprosencephaly, cleft lip/palate, umbilical hernia, omphalocele, cloacal exstrophy, peromelia, polydactyly, and facial abnormalities suggestive of a chromosomal abnormality. We discuss the results in the light of historical and contemporary explanations regarding conjoined twinning, including the opinions of Gerardus and Willem Vrolik and of Louis Bolk, one of their successors.

Silent intracerebral microhemorrhages in patients with ischemic stroke. Amsterdam Vascular Medicine Group.

We compared the frequencies of signs of old intracerebral hemorrhages on brain magnetic resonance imaging scans in 66 patients with ischemic stroke, 69 with myocardial infarction, and 86 with peripheral arterial disease (a total of 221 patients). Magnetic resonance imaging scans were independently assessed by two investigators without knowledge of clinical or laboratory data. In 31 patients (14%) we found local cerebral hemosiderin deposits. In 24 patients they were clinically silent. Hemosiderin deposits were significantly more frequent in patients with ischemic stroke (26%) than in patients with myocardial infarction (4%) or peripheral arterial disease (13%). Hemosiderin deposits were associated with cerebral white matter lesions (odds ratio, 5.3; 95% confidence interval, 2.5-12.4). The odds ratios were higher in patients with severe cerebral white matter lesions. Our findings support the hypothesis that cerebral vessels of patients with ischemic stroke are more prone to rupture than those of patients with other manifestations of atherosclerotic disease, which may explain the higher incidence of intracerebral hemorrhages when these patients are treated with oral anticoagulants. The microhemorrhages were associated with cerebral white matter lesions, which suggests that they are another manifestation of cerebral small-vessel disease.

Predicting survival in patients with early Alzheimer's disease.

We investigated whether an index based on clinical features, electroencephalogram and computed tomography is useful to predict survival in early Alzheimer's disease. One hundred and sixty-three consecutively referred patients to an outpatient memory clinic and first diagnosed with Alzheimer's disease (105 'probable' and 58 'possible', NINCDS-ADRDA criteria) were studied and outcome measure was death. Cox proportional hazards regression analysis and Kaplan-Meier survival curves were used to investigate relations between baseline parameters and survival. Eighty-four patients (51. 5%) died during the follow-up period that extended to 5.8 years, with a median duration of survival after entry of 4.3 years. Baseline factors that were statistically significant and independently related to increased risk of mortality were high age, male sex, poor cognitive function as measured with the CAMCOG, low alpha and beta power on electroencephalogram, and temporoparietal atrophy on computed tomography scan. These results were independent of the diagnosis probable or possible Alzheimer's disease. Based on the coefficients from the regression equation, we computed a survival index for each patient and we constructed three groups according to tertiles of this index. After 5.2 years of follow-up, survival curves showed a low mortality group with 81.7% patients alive (median survival at least 5.7 years), an intermediate mortality group with 35.9% patients alive (median survival 3.8 years), and a high mortality group with no patients alive (median survival 2.3 years). Log rank tests were statistically significant for comparisons between all three groups. We conclude that an overall index combining demographic, cognitive, electroencephalogram and computed tomography features is a strong predictor of survival in early Alzheimer's disease.

Disequilibrium in patients with atherosclerosis: relevance of pontine ischemic rarefaction. Amsterdam Vascular Medicine Group.

OBJECTIVE: To examine the clinical relevance of isolated pontine hyperintense lesions (PHLs) on MRI in patients with atherosclerosis. METHODS: Seventeen atherosclerotic patients with isolated PHL on MRI were compared with 17 patients without PHL and were matched for age, sex, and initial manifestation of atherosclerosis. Subjects and observer were blinded to the MRI findings. We assessed symptoms, impairment, and disability with a structured interview and neurologic examination as well as disability scales. RESULTS: On all items, patients with PHL scored worse than did their controls. We found the largest differences in frequencies of symptoms of disequilibrium, difficulties with speech or swallowing, the Timed Walking Test, and the body care and movement subscale of the Sickness Impact Profile. Except for disequilibrium (p = 0.04), these differences did not reach statistical significance. Abnormal tandem-walking tests were more frequent in patients than they were in controls. Pyramidal signs were equally distributed. CONCLUSIONS: We propose PHL as a cause of symptoms of disequilibrium in patients with atherosclerosis. Symptoms are probably elicited by dysfunction of the corticopontine fibers, the pontocerebellar fibers, or the pontine nuclei.

Quantitative spectral electroencephalography in predicting survival in patients with early Alzheimer disease.

OBJECTIVE: To determine whether measures of quantitative spectral electroencephalography (EEG) can predict survival in patients with early Alzheimer disease. DESIGN: Prospective cohort study; median duration of follow-up was 4.4 years in survivors and 2.6 years in nonsurvivors. Cox proportional hazards models, with adjustment for age and sex were used to estimate relationships between EEG measures and survival. Log relative percentage values of EEG bands were used as predictors. SETTING: Outpatient university memory clinic. PARTICIPANTS: One hundred one consecutively referred patients with early probable Alzheimer disease according to National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria were studied with EEG at the time of diagnosis. The mean age of the patients was 79.2 years, which was higher than in previous EEG studies. MAIN OUTCOME MEASURE: Mortality. RESULTS: Fifty-one patients (50.5%) died during follow-up, with a median survival time in all patients of 4.1 years. The following EEG variables were significantly associated with increased risk of mortality: from parieto-occipital leads, higher theta (hazard ratio, 2.05; 95% confidence interval, 1.15-3.66; P<.05), lower alpha (hazard ratio, 0.43; 95% confidence interval, 0.25-0.76; P<.01), and lower beta (hazard ratio, 0.38; 95% confidence interval, 0.22-0.68; P<.001) activity; and from frontocentral leads, higher theta activity (hazard ratio, 2.07; 95% confidence interval, 1.17-3.66; P<.05). Stepwise Cox regression analysis showed that loss of parieto-occipital beta (P<.01) and alpha (P<.05) power were independent and significant predictors of mortality. Both beta (12.6-35.4 Hz) and alpha (7.5-12.5 Hz) activity remained significantly associated with mortality after adjustment for education, dementia severity, symptom duration, level of cognitive function, presence of extrapyramidal symptoms or hallucinations, presence of vascular risk factors, and presence of leukoaraiosis or local cortical atrophy. CONCLUSIONS: Decreases of beta and alpha activity on quantitative spectral EEG are independent predictors of mortality in patients with early Alzheimer disease. In the clinical context, the use of EEG technology for prediction of survival in individual patients remains to be determined.

Trigeminal neuralgia: comparison of two MR imaging techniques in the demonstration of neurovascular contact.

PURPOSE: To compare two magnetic resonance (MR) imaging techniques for demonstration of vascular contact with the trigeminal nerve. MATERIALS AND METHODS: Thirteen patients with unilateral trigeminal neuralgia and 50 control subjects underwent three-dimensional fast inflow with steady-state precession (FISP) and contrast material-enhanced magnetization-prepared rapid acquisition gradient-echo (MP-RAGE) MR imaging. The images were independently reviewed by two neuroradiologists, who were blinded to the clinical details. Six of the 13 patients underwent surgery. RESULTS: Vascular contact with the trigeminal nerve at the root entry zone was seen on FISP images in 10 of 13 (77%) symptomatic nerves and in eight of 113 (7%) asymptomatic nerves (P < .001). MP-RAGE and FISP images demonstrated arterial contacts equally well. MP-RAGE images demonstrated one additional venous contact at the root entry zone in a patient with ipsilateral trigeminal neuralgia. Interobserver agreement was good for both FISP (kappa = 0.69) and MP-RAGE (kappa = 0.78) images. The presence of vascular contact at the root entry zone, seen on preoperative MR images, was confirmed in all six patients who underwent surgery. CONCLUSION: Both FISP and MP-RAGE MR imaging are useful in demonstrating vascular contact with the trigeminal nerve at the root entry zone in patients with trigeminal neuralgia.

T2-weighted hyperintense MRI lesions in the pons in patients with atherosclerosis. Amsterdam Vascular Medicine Group.

BACKGROUND AND PURPOSE: Pontine hyperintense lesions (PHL) on T2-weighted MRI have been recognized recently. Histopathological findings resemble periventricular leukoaraiosis, and a vascular etiology has been suggested. We studied the frequency and the associated factors of PHL in patients with symptomatic atherosclerosis. METHODS: Two independent observers assessed brain MRIs in a prospective cohort of patients with symptomatic atherosclerosis. Only patients in whom both observers scored PHL on T2- and proton density-weighted images, but not on T1-weighted images, were considered to have the lesion. RESULTS: We studied 229 patients 31% presenting with ischemic stroke, 31% with myocardial infarction, and 38% with peripheral artery disease. Both observers scored PHL in 23% of all patients. Patients with PHL were significantly older and had more lacunar infarcts and periventricular leukoaraiosis than patients without PHL. There were more women, more hypercholesterolemic and diabetic patients, and more cortical infarcts on MRI (P = NS). After logistic regression the presence of leukoaraiosis (odds ratio, 2.4; 95% confidence interval, 1.6 to 3.4) and lacunar infarcts (odds ratio, 2.2, 95% confidence interval, 1.5 to 3.1) remained independently associated with PHL. PHL was more common in patients with ischemic strokes (39%) than in patients with myocardial infarctions (11%) or peripheral artery disease (19%) (P < .001). CONCLUSIONS: We found that PHL on T2- and proton density-weighted MR images are often found in patients with symptomatic atherosclerosis. The association with periventricular leukoaraiosis and lacunar infarcts suggests that PHL is a variant of leukoaraiosis, with possibly the same pathophysiology. The clinical symptoms and consequences of PHL, however, are not yet clear.

Demonstration of a reduction in muscarinic receptor binding in early Alzheimer's disease using iodine-123 dexetimide single-photon emission tomography.

Decreased muscarinic receptor binding has been suggested in single-photon emission tomography (SPET) studies of Alzheimer's disease. However, it remains unclear whether these changes are present in mildly demented patients, and the role of cortical atrophy in receptor binding assessment has not been investigated. We studied muscarinic receptor binding normalized to neostriatum with SPET using [123I]4-iododexetimide in five mildly affected patients with probable Alzheimer's disease and in five age-matched control subjects. Region of interest (ROI) analysis was performed in a consensus procedure blind to clinical diagnosis using matched magnetic resonance (MRI) images. Cortical atrophy was assessed by calculating percentages of cerebrospinal fluid in each ROI. An observer study with three observers was conducted to validate this method. Alzheimer patients showed statistically significantly less [123I]4-iododexetimide binding in left temporal and right temporo-parietal cortex compared with controls, independent of age, sex and cortical atrophy. Mean intra-observer variability was 3.6% and inter-observer results showed consistent differences in [123I]4-iododexetimide binding between observers. However, differences between patients and controls were comparable among observers and statistically significant in the same regions as in the consensus procedure. Using an MRI-SPET matching technique, we conclude that [123I]4-iododexetimide binding is reduced in patients with mild probable Alzheimer's disease in areas of temporal and temporo-parietal cortex.

Perineural tumor extension along the trigeminal nerve: magnetic resonance imaging findings.

OBJECTIVE: To evaluate the magnetic resonance imaging (MRI) findings of 15 patients with perineural tumor extension along the trigeminal nerve in correlation with clinical data. METHODS: The clinical records and MRI studies of 15 patients with perineural tumor extension along the trigeminal nerve were retrospectively reviewed. Imaging studies included plain and contrast-enhanced thin section T1-weighted spin echo (T1-WSE) MRI with and without fat-suppression. The studies were compared to determine which sequence provided greatest tumor conspicuity and best depiction of tumor extent. The conspicuity of these tumors was assessed on the available sequences by two observers by consensus. RESULTS: The contrast-enhanced T1-weighted spin echo fat-suppressed images (T1-WSECEFS) demonstrated greatest tumor conspicuity and best depiction of tumor extent in the extracranial head and neck and skull base region. The conventional T1-weighted spin echo pre- and postcontrast images were, however, diagnostic of perineural tumor extension in 11 patients due to the presence of considerable tumor bulk and extension well above the skull base. In the other four patients the perineural tumor was poorly visualized on the conventional T1-WSE images and well visualized on the fat-suppressed images. The mandibular division of the trigeminal nerve (V3) was most commonly involved (n = 10), followed by the maxillary (V2; n = 5) and ophthalmic (V1; n = 2) division. Two patients had both mandibular as well as maxillary nerve involvement. The finding of perineural tumor extension had significant impact on patient management: based on the MR imaging study, the primary tumor was considered inoperable (n = 13), the extent of surgery was expanded (n = 2) and radiation therapy (RT) ports were extended (n = 12). CONCLUSION: Complete trigeminal nerve imaging is recommended when evaluating (suspected) head and neck malignancies with a high risk for perineural extension. In these cases thin section axial and coronal precontrast T1-WSE MR images and postcontrast T1-WSE MR images with fat-suppression should be obtained. In the rare event that artifacts degrade the quality of the fat-suppressed images, contrast-enhanced T1-WSE sequences without fat-suppression can additionally be used.

Experimental evaluation of scaphoid X-series, carpal box radiographs, planar tomography, computed tomography, and magnetic resonance imaging in the diagnosis of scaphoid fracture.

AIM: In this study, we evaluated scaphoid X-series, Carpal Box radiographs (longitudinal and transverse), planar tomography, computed tomography (CT), and magnetic resonance imaging (MRI) in the diagnosis of scaphoid fracture. The aim of this study was to evaluate the planar technique in the diagnosis of scaphoid fracture. The use of planar tomography, CT, and MRI was to see whether these methods are useful in the diagnosis of scaphoid fracture when other diagnostics modalities remains negative. METHODS: Twenty-eight embalmed human cadaver specimens were used, in 23 of which fractures of the scaphoid were produced mechanically. Scaphoid X-series, Carpal Box posterior-anterior radiographs in ulnar deviation (X-CB), Carpal Box posterior-anterior views with the hand in 15-degree supination and ulnar deviation (X-CB 15-degree) were acted in all specimens, CT in eight wrists, planar tomography in seven wrists, and MRI in five wrists. The anatomic analysis of the specimens was used as the gold standard for comparison. Scaphoid X-series, Carpal Box radiographs, and planar tomography were judged independently and in a blind fashion by six observers, and CT and MRI were also judged independently and in a blind fashion by three radiologists. The observers were asked if they could recognize a scaphoid fracture. The agreement among the six observers for the scaphoid X-series and X-CB was measured. RESULTS: In the 23 fractured wrists, scaphoid X-series, X-CB, X-CB 15-degree, was true positive in 12, 14, and 15 wrists, respectively, whereas these methods were true negative in cadaver wrists 1, 3, and 5. CT was true positive in five of five fractured wrists and true negative in three of three negative wrists. Planar tomography was true positive in one of four fractured wrists and true negative in two of three nonfractured wrists. MRI was obtained in five wrists (one without a fracture), of which the fracture was recognized in only two. The highest agreement between observers was found in the X-CB 15-degree. CONCLUSION: From the planar investigated methods, the 15-degree Carpal Box posterior-anterior, longitudinal and transverse views were most accurate in recognizing scaphoid fracture with also the highest agreement between the observers.