MRI and neurological findings in patients with spinal metastases.

BACKGROUND: Magnetic resonance imaging (MRI) is the recommended primary investigation method for metastatic spinal cord compression (MSCC). Initiating treatment before the development of motor deficits is essential to preserve neurological function. However, the relationship between MRI-assessed grades of spinal metastatic disease and neurological status has not been widely investigated. PURPOSE: To analyze the association between neurological function and MRI-based assessment of the extent of spinal metastases using two different grading systems. MATERIAL AND METHODS: A total of 284 patients admitted to our institution for initial radiotherapy or surgery for symptomatic spinal metastases were included in the study. Motor and sensory deficits were categorized according to the Frankel classification system. Pre-treatment MRI evaluations of the entire spine were scored for the extent of spinal metastases, presence and severity of spinal cord compression, and nerve root compression. Two MRI-based scales were used to evaluate the degree of cord compression and spinal canal narrowing and relate these findings to neurological function. RESULTS: Of the patients included in the study, 28 were non-ambulatory, 49 were ambulatory with minor motor deficits, and 207 had normal motor function. Spinal cord compression was present in all patients with Frankel scores of B or C, 23 of 35 patients with a Frankel score of D (66%), and 48 of 152 patients with a Frankel score of E (32%). The percentage of patients with severe spinal canal narrowing increased with increasing Frankel grades. The grading according to the scales showed a significant association with the symptoms according to the Frankel scale (P < 0.001). CONCLUSION: In patients with neurological dysfunction, the presence and severity of impairment was associated with the epidural tumor burden. A significant number of patients had radiological spinal cord compression and normal motor function (occult MSCC).

Low frequency of VHL germline mutations in Norwegian patients presenting with isolated central nervous system hemangioblastomas--a population-based study.

OBJECTIVES: Explore the genetic and clinical incidence of von Hippel-Lindau disease in patients presenting with isolated central nervous system hemangioblastomas. RESULTS: We report a 3.2% (1/31) and 25% (8/32) incidence of genetic and clinical VHL, respectively. One patient tested positive for a VHL mutation that has not previously been reported. This genotype phenotypically predicts VHL type 2B. We had seven patients with renal cysts. In a total follow-up of 33 person years, none of these cysts progressed to renal cell carcinoma. CONCLUSION: von Hippel-Lindau disease anchored in germline mutations of the VHL gene is rare in the Norwegian population as opposed to clinical VHL disease, which appears to be relatively common in patients with apparently sporadic hemangioblastomas. There exists insufficient data regarding the natural history of patients with renal cysts, which makes it difficult to include or disregard these lesions as an entity of VHL disease.

Spindle cell oncocytoma of the adenohypophysis: report of a case with marked cellular atypia and recurrence despite adjuvant treatment.

Spindle cell oncocytoma (SCO) of the adenohypophysis is a recently defined pituitary tumor mimicking a non-functioning macroadenoma and composed of mitochondrion rich tumor cells, positive for S-100, vimentin, epithelial membrane antigen and galectin-3 but lacking cytokeratins, pituitary hormones, and neuroendocrine markers. Derivation from pituitary folliculostellate cells (FSCs) has been suggested based upon immunohistochemical and ultrastructural characteristics shared by SCO and FSCs. 10 cases of SCO have been reported to date; of these, 8 underwent a benign clinical course and 2 recurred. We report a case of SCO with typical histologic and immunohistochemical features in addition to marked cellular pleomorphism and nuclear atypia. It showed slow regrowth over a 30-month period of follow-up despite combined surgical and radiotherapy. Despite the benign course of most reported cases, additional experience with longer follow-up are needed to assess clinical, histopathologic, and proliferative indices and their relevance to optimal therapy for this rare pituitary tumor.

A piglet model for detection of hypoxic-ischemic brain injury with magnetic resonance imaging.

BACKGROUND: Early detection of hypoxic-ischemic (HI) injury in the asphyxic newborn is important because present prognostic factors are inadequate. Furthermore, therapeutic interventions may have additional benefit if initiated in time. PURPOSE: To assess whether the use of a combined protocol including conventional magnetic resonance imaging (MRI), diffusion-weighted imaging (DWI), diffusion tensor imaging (DTI), and proton MR spectroscopy (MRS) could detect pathological findings in a piglet model 7 hours after HI. MATERIAL AND METHODS: Ten piglets were submitted to HI for 30 min followed by reoxygenation with 21% O2 for 7 hours. MRI at 1.5T was done prior to and 7 hours after the HI. Single-voxel proton MRS was performed, and apparent diffusion coefficient (ADC) and fractional anisotropy (FA) were measured in the basal ganglia. MRS identified N-acetylaspartate (NAA), choline (Cho), creatine (Cr), and lactate (Lac). Histology and microtubule-associated protein 2 (MAP-2) staining was performed in the basal ganglia at the end of the experiment. RESULTS: Compared to baseline, ADC, NAA/Cho, and NAA/Cr were significantly reduced after 7 hours (P<0.001, P=0.01, and P=0.05, respectively) and FA values were increased (P<0.025). The ratios of Lac/Cho and Lac/NAA were significantly higher after 7 hours compared to baseline (P<0.001). Presence of necrosis correlated well with reduced ADC (R(S)=0.91) and presence of Lac (R(S)=0.80). Histology and MAP-2 staining showed more than 90% necrosis in eight piglets, 60% in one piglet, and no necrosis in one piglet. CONCLUSION: Diffusion MRI and proton MRS can detect HI injury in the piglet brain 7 hours after hypoxia. DWI and MRS can be used to give useful prognostic information. This piglet model may potentially be used to mimic clinical situations and is suitable for further research investigating HI injury.

Prognostic factors in patients with symptomatic spinal metastases and normal neurological function.

AIMS: To evaluate potential prognostic factors for predicting survival after radiotherapy in patients with painful spinal metastases and normal neurological function. MATERIALS AND METHODS: In total, 173 patients were included. The following prognostic factors were assessed: primary cancer site, age, gender, albumin and haemoglobin levels, Karnofsky performance status (KPS), analgesic use, pain intensity, number of extraspinal bone metastases and visceral metastases, presence of tumour-conditioned spinal canal stenosis and metastatic spinal cord compression, and extension of spinal metastatic disease on magnetic resonance imaging (MRI). Ongoing systemic treatment, use of bisphosphonates and response to radiotherapy were also evaluated. A simple scoring system for predicting survival was used. RESULTS: The following predictive factors were found to be significant in multivariate analysis: primary cancer site, KPS, albumin level, number of visceral metastases and analgesic use. Three survival groups were proposed. The overall survival probabilities for groups 1-3 were 13, 46 and 94% at 6 months; 4, 28 and 79% at 12 months, respectively. The median survival times for groups 1-3 were 2.1, 5.5 and 24.9 months, respectively (P < 0.001). CONCLUSION: The pretreatment albumin level was a significant prognostic indicator for survival. Similarly, the primary cancer site, KPS and number of visceral metastases were associated with survival; these findings were consistent with the results of previous studies. The pretreatment analgesic use was significant using the univariate and multivariate analyses and this factor can be verified in future trials. Self-reported pain intensity, pain response to radiotherapy and MRI findings did not influence survival times.

Bilateral arachnoid cysts of the temporal fossa in four children with glutaric aciduria type I.

Glutaric aciduria type I is an uncommon inborn error of metabolism. It is a serious disease, often with a fatal outcome. This study reports the presence of bilateral temporal fluid collections, probably bilateral arachnoid cysts, in association with glutaric aciduria type I. The CT and, when available, MR studies from five patients with this disorder were reviewed. Four of the patients had findings consistent with bilateral arachnoid cysts of the temporal fossa. This is a rare occurrence, with only 11 such cases reported in the literature. The observed association between temporal fluid collections and glutaric aciduria type I suggests that patients with bilateral arachnoid cysts should be investigated for this metabolic disorder.

Craniopharyngioma: radiologic and histologic findings and recurrence.

PURPOSE: To identify the CT and MR characteristics of craniopharyngiomas, to evaluate the histologic types of craniopharyngioma, and to compare the radiologic/histologic appearance and type of therapy with tumor recurrence. METHODS: We reviewed the records of 45 patients with craniopharyngiomas for which surgical specimens (n = 45), preoperative MR or CT studies (n = 27), or other MR or CT studies or reports (n = 18) were available. Radiologic appearance, histologic morphology, treatment, and tumor recurrence were studied. RESULTS: Adamantinomatous epithelium was found in 40 of 45 surgical specimens, keratin in 34 of 45, and squamous epithelium in 11 of 45. A continuum of mixed morphology rather than distinct subtypes of tumors was found. The radiologic appearance did not correlate with the histologic features. No statistically significant difference was found between children and adults with respect to tumor size, calcification, histology, or tumor recurrence. Patients treated with radiation after subtotal resection had far fewer tumor recurrences (n = 3) than patients treated with surgery alone (n = 18). CONCLUSION: Craniopharyngiomas could not be divided into distinct histologic types. No differentiating radiologic or histologic characteristics could be established for craniopharyngiomas in children versus adults. Radiation treatment was strongly associated with tumor regression or lack of recurrence.

Adverse reactions to intravenous cholangiography with Biligram.

During the seven year period 1976-82 3937 intravenous cholangiographies were performed with thirty-three adverse reactions to the contrast medium Biligram considered to require treatment. One patient died. The frequency of adverse reactions to intravenous cholangiography with Biligram is no reason for abandoning the method.

[Aneurysms of the vein of Galen. Angiographic study and morphogenetic considerations]. / Les anévrysmes de la veine de Galien. Etude angiographique et considérations morphogénétiques.

The angiographic and/or anatomic study of a series of 30 cases of Vein of Galen aneurysm (which is defined as an arterio-venous fistula within the wall of the vein of Galen itself, therefore as a purely extra cerebral lesion) permits the analysis of the afferent arteries, of the efferent veins, and of the aneurysmal sac itself. The examination of the afferent arteries confirms the data from the literature, indicating that most often it consists of the abnormal hypertrophy of otherwise normally organized arteries, including the dural arteries. In particular, the involvement of distal subcallosal branches of the anterior cerebral arteries as well as the arterio-arterial maze extending above the collicular plate, fit well the normal anatomy. The venous side of the malformation nevertheless presents with more unusual features; the most striking is the non-opacification of the straight sinus and/or part of the transverse sinuses in half of the cases; also, an aberrant falcine sinus is frequently observed, which actually represents the persistence of a normal channel in the fetal anatomy. A more complex pattern was observed in two cases in which the aneurysmal sac drained into the straight sinus via a loop made of a falcine sinus, the superior sagittal sinus and then backward through a second falcine sinus. Finally, from the systematization of the afferents arteries, the aneurysmal sac appears to belong both to the (prosencephalic) velum interpositum and to the ambient cistern. Such a vessel cannot be either the true vein of Galen or an internal cerebral vein; therefore it has to be a persistent fetal vein, the median prosencephalic vein, which drains the choroid plexuses of the lateral and third ventricles between the 7th and 12th weeks, and disappears normally to be replaced by the internal cerebral veins, when the intrinsic vascularization of the neural tube develops. The adult pattern of the brain artery being attained during the 8th week, the event that led to the arterio venous fistula should have occurred some time during the 3rd month. Unfortunately, no clue was found to orient to a specific cause for the anomaly. The frequently observed venous occlusions are actually not seen in neonates but rather in older children. This, and the fact that spontaneous thromboses within the malformative veins have been observed in vivo, make likely the conclusion that venous occlusions are a secondary phenomenon only.

Dural ectasia in Marfan syndrome: a case control study.

BACKGROUND AND PURPOSE: Dural ectasia (DE) is one of the major criteria of Marfan syndrome (MFS). Our aim was to establish the prevalence of DE in an adult population fulfilling the Ghent criteria for MFS and to assess definitions of DE. MATERIALS AND METHODS: One hundred five adults with suspected MFS were included. MR imaging at 1.5T was performed unless contraindicated; then CT was obtained. Lumbosacral anteroposterior vertebral body diameters (VBD) and dural sac diameters (DSD) were measured. Dural sac ratios (DSR = DSD/VBD) at levels L3 through S1 were calculated. Anterior meningoceles, herniations of nerve root sleeves, and scalloping were characterized. One hundred one sex- and age-matched patients were included as controls. RESULTS: We identified 3 patient groups: 1) fulfilling Ghent criteria independent of DE (n = 73), 2); fulfilling Ghent criteria dependent on DE (n = 14), and 3); and suspected MFS, not fulfilling Ghent criteria (n = 18). DE was found in 86% of group 1. At levels L4-S1, mean DSRs were significantly higher in group 1 than in group 3 and controls (P < .001). Herniations of the nerve root sleeves were present in 73% in group 1 versus 1% in controls. Anterior meningoceles were found in 37% and 14% in groups 1 and 2, respectively, but not in group 3 or controls. CONCLUSIONS: The diagnosis of DE on MR imaging or CT should be based on the presence of at least 1 of the following criteria: anterior meningoceles or nerve root sleeve herniation, DSD at S1 or below larger than DSD at L4, and DSR at S1 >0.59.

Histogram analysis of MR imaging-derived cerebral blood volume maps: combined glioma grading and identification of low-grade oligodendroglial subtypes.

BACKGROUND AND PURPOSE: Inclusion of oligodendroglial tumors may confound the utility of MR based glioma grading. Our aim was, first, to assess retrospectively whether a histogram-analysis method of MR perfusion images may both grade gliomas and differentiate between low-grade oligodendroglial tumors with or without loss of heterozygosity (LOH) on 1p/19q and, second, to assess retrospectively whether low-grade oligodendroglial subtypes can be identified in a population of patients with high-grade and low-grade astrocytic and oligodendroglial tumors. MATERIALS AND METHODS: Fifty-two patients (23 women, 29 men; mean age, 52 years; range, 19-78 years) with histologically confirmed gliomas were imaged by using dynamic susceptibility contrast MR imaging at 1.5T. Relative cerebral blood volume (rCBV) maps were created, and 4 neuroradiologists defined the glioma volumes independently. Averaged over the 4 observers, a histogram-analysis method was used to assess the normalized histogram peak height of the glioma rCBV distributions. RESULTS: Of the 52 patients, 22 had oligodendroglial tumors. The histogram method was able to differentiate high-grade gliomas (HGGs) from low-grade gliomas (LGGs) (Mann-Whitney U test, P < .001) and to identify low-grade oligodendroglial subtypes (P = .009). The corresponding intraclass correlation coefficients were 0.902 and 0.801, respectively. The sensitivity and specificity in terms of differentiating low-grade oligodendroglial tumors without LOH on 1p/19q from the other tumors was 100% (6/6) and 91% (42/46), respectively. CONCLUSION: With histology as a reference, our results suggest that histogram analysis of MR imaging-derived rCBV maps can differentiate HGGs from LGGs as well as low-grade oligodendroglial subtypes with high interobserver agreement. Also, the method was able to identify low-grade oligodendroglial tumors without LOH on 1p/19q in a population of patients with astrocytic and oligodendroglial tumors.

[Neurologic magnetic resonance tomography--indications and practical use]. / Nevroradiologisk magnetisk resonanstomografi--indikasjoner og bruksområder.

Magnetic resonance tomography is considered the most important technique in modern neuroradiology. This article demonstrates the importance of MR imaging in the diagnosis of diseases of the central nervous system. Modern neuroradiology is completely dependent upon this modality, and sections and departments of neuroradiology should have great responsibility for both diagnostic MR imaging and the day-to-day operation MR laboratories.

Coronal MR imaging of the normal 3rd, 4th, and 5th lumbar and 1st sacral nerve roots.

Seven healthy volunteers underwent coronal MR imaging at 1.5 tesla of the normal 3rd, 4th, and 5th lumbar, and 1st sacral nerve roots. Coronal slices, 3-mm-thick with a 0.3-mm gap between the slices were obtained (TR/TE 600/22) through the lumbar spinal canal. All the nerve roots were visible on at least one image. One can routinely expect to demonstrate the 3rd, 4th, and 5th lumbar, and 1st sacral nerve roots on T1-weighted, 3-mm-thick coronal MR scans. We found no correlation between the degree of lumbar lordosis and the lengths of the visible nerve roots. Five patients with one of the following spinal problems: anomaly, tumor, disk herniation, and failed back surgery syndrome were examined according to our protocol. In all these cases coronal MR imaging gave the correct diagnosis.

Multiple spinal arteriovenous fistulas in Klippel-Trenaunay-Weber syndrome treated with platinum fibre coils.

A 13-year-old girl with Klippel-Trenaunay-Weber syndrome and intradural extramedullary spinal arteriovenous fistulas is presented. Pre-embolization balloon test occlusions and embolization with platinum fibre coils were carried out in three sessions, after which the myelopathy and the intense back pain disappeared. Our conclusion is that spinal fistulas can be safely and effectively treated with fibre coils in combination with balloon testing.

Embolization of intracranial arteriovenous malformations and fistulas with polyvinyl alcohol particles and platinum fibre coils.

In order to reduce the recanalization rate of arteriovenous malformations and multiple dural arteriovenous fistulas, embolization was carried out with polyvinyl alcohol (PVA) particles combined with platinum fibre coils in 20 patients. The malformation was occluded more effectively than by PVA alone. Distal deposition of the emboli was obtained by improved steerable catheters (Tracker-18-unibody) and guidewires. The complication rate was lower than usually reported from studies using glue as embolic agent. It was concluded that the combination of PVA and fibre coils enhances the safety and effectiveness of embolization therapy and reduces the frequency of recanalization of intracranial AVMs.

Carotid-cavernous fistula treated with detachable balloon during bilateral transcranial Doppler monitoring of middle cerebral arteries. A case report.

A traumatic carotid-cavernous fistula was closed with a silicone detachable balloon. Prior to the closure of the fistula, clinical and transcranial Doppler testing was performed in order to evaluate the consequences of a possible occlusion of the carotid artery. A newly developed Doppler technique with bilateral simultaneous velocity recordings of the middle cerebral arteries was useful during the procedure. The detachable balloon was effective in closing the fistula, but collapse of the balloon and the development of an extradural aneurysm was found at control examinations.

Aneurysms of the vein of Galen: embryonic considerations and anatomical features relating to the pathogenesis of the malformation.

Vein of Galen aneurysms may be defined as direct arteriovenous fistulas between choroidal and/or quadrigeminal arteries and an overlying single median venous sac. Anatomic analysis of 23 cases of vein of Galen aneurysm and correlation with known embryologic data indicate that the venous sac most probably represents persistence of the embryonic median prosencephalic vein of Markowski, not the vein of Galen, per se. The frequent concurrent venous abnormalities are easily understood as (a) retention of fetal anatomical features and (b) frequent occlusions of the dural sinuses of the posterior fossa, especially the sigmoid sinuses.

Craniopharyngioma identification by CT and MR imaging at 1.5 T.

To compare the detectability of craniopharyngiomas by CT and MR imaging, preoperative CT and MR studies obtained within 16 days of each other were evaluated retrospectively in 9 patients. MR imaging demonstrated cystic and solid tumor components in all 9 tumors, and enhancement in the 7 tumors that were studied after contrast medium injection. MR imaging demonstrated a signal void consistent with calcification in 4 patients. Combining unenhanced and contrast medium-enhanced studies, CT also identified all the tumors. CT demonstrated cysts in 7 lesions, calcification in 7 and enhancement in 6 of the 7 lesions that received i.v. contrast medium. Calcification was better seen by CT than MR imaging, while MR imaging identified cystic tumor components not seen on CT. The contrast medium enhancement pattern was the same with the 2 modalities. MR imaging of the sellar region, including at least one contrast medium-enhanced sequence, should be sufficient in most instances to establish a preoperative diagnosis of craniopharyngioma.

Features resisting primary treatment of congenital club foot.

The aims of this study were: (1) to see whether the number of relapses of hindfoot deformity in congenital club foot in the first year of life could be reduced by operative treatment, and (2) to try by surgery to pinpoint features of congenital club feet that make them resistant to treatment. As compared to treatment of 95 feet with manipulation and plaster cast only or with heel cord tenotomy added, early tenotomy of both the heel cord and the tibialis posterior tendon in 23 feet markedly reduced the number of relapses of hindfoot deformity, and the need for additional treatment. The results indicate that the achilles and the tibialis posterior tendons, and their corresponding muscles, are the main dynamic features that need to be dealt with when treating the hindfoot deformity in congenital club foot.