Follow-up MR imaging of the alar and transverse ligaments after whiplash injury: a prospective controlled study.

BACKGROUND AND PURPOSE: The cause and clinical relevance of upper neck ligament high signal intensity on MR imaging in WAD are controversial. The purpose of this study was to explore changes in the signal intensity of the alar and transverse ligaments during the first year after a whiplash injury. MATERIALS AND METHODS: Dedicated high-resolution upper neck proton attenuation-weighted MR imaging was performed on 91 patients from an inception WAD1-2 cohort, both in the acute phase and 12 months after whiplash injury, and on 52 controls (noninjured patients with chronic neck pain). Two blinded radiologists independently graded alar and transverse ligament high signal intensity 0-3, compared initial and follow-up images to assess alterations in grading, and solved any disagreement in consensus. The Fisher exact test was used to compare proportions. RESULTS: Alar and transverse ligament grading was unchanged from the initial to the follow-up images. The only exceptions were 1 alar ligament changing from 0 to 1 and 1 ligament from 1 to 0. The prevalence of grades 2-3 high signal intensity in WAD was thus identical in the acute phase and after 12 months, and it did not differ from the prevalence in noninjured neck pain controls (alar ligaments 33.0% versus 46.2%, P = .151; transverse ligament 24.2% versus 23.1%, P = 1.000). CONCLUSIONS: Alar and transverse ligament high signal intensity in patients with WAD1-2 observed within the first year after injury cannot be explained by the trauma. Dedicated upper neck MR imaging cannot be recommended as a routine examination in these patients.

CT and MR imaging features of primary central nervous system lymphoma in Norway, 1989-2003.

BACKGROUND AND PURPOSE: Studying imaging findings of non-acquired immunodeficiency syndrome (AIDS) primary central nervous system lymphoma (PCNSL), we hypothesized that the imaging presentation has changed with the increasing incidence of PCNSL and is related to clinical factors (eg, time to diagnosis and the patient's being diagnosed alive or at postmortem examination). MATERIALS AND METHODS: Chart and histologic reviews of patients recorded as having PCNSL during 1989-2003 in the Norwegian Cancer Registry identified 98 patients with non-AIDS PCNSL; 75 had available imaging. CT and MR images from the first diagnostic work-up after onset of symptoms but before histologic diagnosis were reviewed. RESULTS: CT and/or MR imaging in the 75 patients revealed no lesion in 10 (13%), a single focal lesion in 34 (45%), multiple focal lesions in 26 (35%), and disseminated lesions in 5 (7%) patients. All together, we identified 103 focal lesions (single/multiple): 63% in white matter, 56% abutting the ventricular surface, and 43% in the frontal lobes); 100% (102/102 lesions evaluated with contrast) showed contrast enhancement. The median time from imaging to diagnosis for patients with no, single, multiple, or disseminated lesions was 32, 3, 5, and 3 weeks, respectively (P = .01). Patients with no or disseminated lesions were more often diagnosed at postmortem examination (P = .06). Imaging findings were practically unchanged during the consecutive 5-year periods. CONCLUSIONS: White matter periventricular contrast-enhancing single or multiple focal lesions were typical of non-AIDS PCNSL. No or disseminated lesions heightened the risk of delayed or postmortem diagnosis. Although the incidence of non-AIDS PCNSL has increased, its presentation at imaging remains unchanged.

Pilomyxoid astrocytoma: expanding the imaging spectrum.

BACKGROUND AND PURPOSE: Pilomyxoid astrocytoma (PMA) is a recently described variant of pilocytic astrocytoma (PA) with unique clinical and histopathologic characteristics. Because the histopathology of PMA is distinct from that of PA, we hypothesized that PMAs would display distinctive imaging characteristics. We retrospectively reviewed the imaging findings in a large number of patients with PMA to identify these characteristics. MATERIALS AND METHODS: CT and MR images, pathology reports, and clinical information from 21 patients with pathology-confirmed PMA from 7 institutions were retrospectively reviewed. CT and MR imaging findings, including location, size, signal intensity, hemorrhage, and enhancement pattern, were tabulated. RESULTS: Patients ranged in age from 9 months to 46 years at initial diagnosis. Sex ratio was 12:9 (M/F). Twelve of 21 (57%) tumors were located in the hypothalamic/chiasmatic/third ventricular region. Nine (43%) occurred in other locations, including the parietal lobe (2/21), temporal lobe (2/21), cerebellum (2/21), basal ganglia (2/21), and fourth ventricle (1/21). Ten (48%) tumors showed heterogeneous rim enhancement, 9 (43%) showed uniform enhancement, and 2 (9%) showed no enhancement. Five (24%) masses demonstrated intratumoral hemorrhage. CONCLUSION: This series expands the clinical and imaging spectrum of PMA and identifies characteristics that should suggest consideration of this uncommon diagnosis. One third of patients were older children and adults. Almost half of all tumors were located outside the typical hypothalamic/chiasmatic region. Intratumoral hemorrhage occurred in one quarter of patients. PMA remains a histologic diagnosis without definitive imaging findings that distinguish it from PA.

IL-6: an early marker for outcome in acute ischemic stroke.

OBJECTIVES: Inflammation plays an important role in the pathophysiology of stroke. We correlated interleukin (IL)-6, IL-10, C-reactive protein (CRP) and T-lymphocyte subtype levels in acute ischemic stroke patients with stroke volume and clinical outcome. MATERIALS AND METHODS: Blood samples were obtained from 11 patients at defined intervals during 1 year. Nine healthy age-matched subjects served as controls. IL-6, IL-10 and CRP were quantified by enzyme-linked immunosorbent assay and T lymphocytes by flow cytometry. Volume measurement was carried out by computed tomography or magnetic resonance imaging and clinical outcome was scored by the European stroke scale (ESS) and Barthel index (BI). RESULTS: IL-6 levels were increased in the acute phase of stroke compared with healthy controls (P = 0.002) and correlated with larger stroke volume (P = 0.012) and less favorable prognosis after 1 year, measured by ESS (P = 0.014) and BI (P = 0.006). IL-10, CRP and T-lymphocyte subtypes in the acute phase were not correlated with stroke volume or clinical outcome. CONCLUSION: IL-6 seems to be a robust early marker for outcome in acute ischemic stroke.

MR analysis of the transverse ligament in the late stage of whiplash injury.

PURPOSE: To analyse and classify structural changes in the transverse ligament in the late stage of whiplash injury by use of high-resolution MRI, and to evaluate the reliability of our classification. MATERIAL AND METHODS: Ninety-two whiplash-injured (2-9 years previously, mean 6 years) and 30 non-injured individuals underwent proton-weighted MR imaging of the craniovertebral junction in three orthogonal planes. Structural changes in the transverse ligaments were graded twice (grades 1-3) based on increased signal, independently by 3 radiologists with a 4-month interval. Inter- and intraobserver statistics were calculated by ordinary and weighted kappa (K). RESULTS: Image quality was excellent in 109 cases and slightly reduced in 13. Twenty-two out of 30 ligaments in the control group were classified as normal (73%) compared with only 32 out of 92 in the injured group (36%). Two or all 3 observers agreed in their grading in 101 out of 122 ligaments (83%). Intraobserver agreement (weighted K) was fair to good (0.33-0.73). Pair-wise interobserver agreement was fair (0.24-0.39). Reasons for divergent grading were insufficient knowledge of normal variations, low signal intensity in the peridental soft tissue obscuring the ligament and interpretation flaw. CONCLUSION: Whiplash trauma can damage the transverse ligament. By use of high-resolution proton-weighted MR images such lesions can be detected and classified. The reliability of this classification still needs improvement.

MRI of the tectorial and posterior atlanto-occipital membranes in the late stage of whiplash injury.

Our aim was to characterise and classify permanent structural changes in the tectorial and posterior atlanto-occipital membranes several years after a whiplash injury, and to evaluate the reliability of our classification. We obtained sagittal proton density-weighted images of the craniovertebral junction of 92 whiplash-injured and 30 uninjured individuals. Structural abnormalities in the two membranes were classified as grades 1-3 independently by three radiologists blinded for clinical information. Grading criteria were based on reduced tectorial membrane thickness, and elongation or rupture of the posterior atlanto-occipital membrane/dura mater complex. The same images were reassessed 4 months later. Image quality was graded good in 104 cases, slightly reduced in 13 and unsatisfactory in five. Of 117 tectorial membranes 31 (26.5%) showed grade 2 or 3 lesions, in the uninjured group none were grade 3 and only three were grade 2. Pair-wise interobserver agreement (weighted kappa) was moderate (0.47-0.50), while the intraobserver agreement was moderate to good (0.51-0.70). Of 117 posterior atlanto-occipital membranes 20 (17.1%) had grade 2 or 3 lesions; there was no grade 3 and only one grade 2 lesion in the uninjured group. Inter- and intraobserver agreement was good (0.61-0.74 and 0.65-0.86, respectively). Reduced image quality was the main reason for disagreement, but partial thinning and lateral tapering, as normal tectorial membrane variations, created difficulties in some cases. This study strongly indicates that whiplash trauma can damage the tectorial and posterior atlanto-occipital membranes; this can be shown on high-resolution MRI. Better knowledge of normal anatomical variations and improved image quality should increase the reliability of lesion classification.

MRI assessment of the alar ligaments in the late stage of whiplash injury--a study of structural abnormalities and observer agreement.

Our aim was to characterise and classify structural changes in the alar ligaments in the late stage of whiplash injuries by use of a new MRI protocol, and to evaluate the reliability and the validity of this classification. We studied 92 whiplash-injured and 30 uninjured individuals who underwent proton density-weighted MRI of the craniovertebral junction in three orthogonal planes. Changes in the alar ligaments (grades 0-3) based on the ratio between the high signal area and the total cross-sectional area were rated twice at a 4-month interval, independently by three radiologists. Inter- and intraobserver statistics were calculated by ordinary and weighted kappa. Cases classified differently were reviewed to identify potential causes for disagreement. The alar ligaments were satisfactorily demonstrated in all cases (244 ligaments in 122 individuals). The lesions, 2-9 years after the injury, varied from small high-signal spots to high signal throughout the cross-sectional area. Signal was highest near the condylar insertion in 82 of 94 ligaments, indicating a lesion near that insertion, and near the dental insertion in eight, indicating a medial lesion. No grade 2 or 3 lesion was found in the control group. At least two observers assigned the same grade to 214 ligaments (87.7%) on the second occasion. In 30 ligaments (12.3%) this agreement was not obtained. Pair-wise interobserver agreement (weighted kappa) was fair to moderate (0.31-0.54) in the first grading, improving to moderate (0.49-0.57) in the second. Intraobserver agreement (weighted kappa) was moderate to good (0.43-0.70). Whiplash trauma can cause permanent damage to the alar ligaments, which can be shown by high-resolution proton density-weighted MRI. Reliability of classification of alar ligament lesions needs to be improved.

Vertical displacement of the brain and the target area during open stereotaxic neurosurgery.

During stereotaxic thalamotomies, we observed that the brain surface was sinking. The study was carried out to investigate to what extent the target area also was displaced and how this would affect the accuracy of the stereotaxic procedure. In 12 thalamotomies, with the patients operated on in the sitting position, we found that the cortical surface sank 0-9 (mean 5) mm during the operation. The vertical co-ordinate of the thalamic target was consequently adjusted per-operatively, and the electrodes were advanced an additional distance of 1-5.5 (mean 3.5) mm in an attempt to compensate for the assumed sinking of the target. This per-operative adjustment was based on the surgeon's experience and the results of macro-stimulation studies. The exact location of the thalamotomy lesion, and thereby the accuracy of the adjustment, was evaluated on 3 months postoperative CT scans. These showed that the intended target was hit with a sufficient degree of accuracy in all the patients, although the vertical co-ordinate had been slightly over-adjusted, as the center of the lesion on the average was located 1 mm below the intended location. Thus, if the vertical position had not been adjusted, the lesion would on the average have been located 2.5 mm too high compared with the intended target. Patients undergoing thalamotomy and other stereotaxic procedures, where a high degree of accuracy is needed, should be operated on in the sitting position. At the thalamic level, the vertical displacement of the target should be adjusted for by additional advancement of the stereotaxic probe. On average, this compensatory adjustment should be about half the per-operative sinking of the cortical surface.

[Neuromuscular complications of myxoma]. / Nevrologiske komplikasjoner til myksom.

BACKGROUND: Myxomas are the most common type of primary cardiac tumours. As they are most often located in the left atrium, primary neurological manifestations are often multiple embolic infarcts in the central nervous system. MATERIAL AND METHODS: We describe a patient with acute aphasia due to left temporal haemorrhage. Later he developed acute ataxia due to right cerebellar infarct. RESULTS: Magnetic resonance also showed multiple supra- and infratentorial infarcts. Echocardiography revealed a myxoma in the left atrium which was treated by surgical excision. There were no signs of myxoma recurrence or embolic infarcts at follow-up. INTERPRETATION: Echocardiography should be included in the diagnostic work-up of patients with cerebrovascular events, especially in young patients with multiple infarcts.

MRI assessment of normal ligamentous structures in the craniovertebral junction.

We have established an imaging protocol in order to characterise the normal ligamentous structures in the craniovertebral junction. Thirty volunteers without a history of car accident or head or neck trauma underwent MR imaging with 2-mm-thick proton-density-weighted sections in three orthogonal planes. The alar ligaments were clearly seen in every case and had three different configurations in cross-section: round, ovoid or wing-like. A broadening from lateral to medial in the coronal plane was observed in all cases. The transverse ligament was clearly demonstrated in 26 out of 30 cases. The ligament was flattened where it arched across the dens. Towards the insertions the ligament twisted into an oblique-horizontal orientation. The lower tectorial membrane had a median portion merging with the dura, and a lateral portion separated from it. Between the dens and clivus this membrane either merged totally with dura or was partly separated from it by a thin layer of fat. The posterior atlanto-occipital membrane was clearly demonstrated. It either merged with the dura or was partly or totally separated from it by a fat layer. The anterior atlanto-occipital membrane was inconsistently seen and could not be evaluated. Our refined MR protocol improves the visualisation of the craniovertebral ligamentous structures, and may in the future give new insight into post-traumatic neck disorders up to now poorly understood.

Acoustic neuroma--treatment modalities. Surgery, gamma-knife or observation?

We present our results of 211 patients with acoustic neuroma over a period of 10 years, 1988-97. We operated on 100 and 111 had Gamma-knife (GK) treatment (69 were available to follow-up). The results are excellent for surgery on small and intracanalicular tumours. In tumours of the same size, surgery and GK treatment give comparable, but somewhat different, results. In the GK group of 54 primary treated patients, 3 patients had to be operated on and another 4 developed hydrocephalus. A group of 35 acoustic tumours was observed for more than 3 years. Nineteen did grow (54%). Hearing was unchanged in 23%. We performed surgery in 11 patients and gave 2 patients GK treatment because of tumour growth of > 2 mm in diameter a year. We conclude that either treatment is effective for small and medium-sized acoustic neuromas. Hearing preservation was best in the GK-treated group (80%), compared to only 12.5% in the group operated via the suboccipital route. Larger tumours and most medium-sized tumours should be operated, as should smaller tumours with persistent symptoms of vertigo and pain. Medical contraindications to surgery or reluctance to undergo surgery make GK treatment a good alternative. Treatment of residual tumours with the GK could also be a solution to a difficult problem.

[Dolichoectasia of the intracranial arteries and stroke]. / Dolikoektasi av intrakraniale arterier og hjerneslag.

Intracranial arterial dolichoectasia is a condition related to stroke. The prevalence in patients suffering from their first cerebral infarction is estimated to be 3%. Patients with dolichoectasia are more likely to have lacunar infarctions than those without. They have a higher survival rate and better functional prognosis after first cerebral infarction, but a higher rate of stroke recurrence. The aetiology and pathogenesis of the condition is unknown. Only 0.5% of patients suffering a first cerebral infarction have dolichoectasia of both the carotid and vertebrobasilar system. We describe a case of atypical dolichoectasia affecting both circulatory systems as well as the middle and anterior cerebral arteries, with intracerebral haemorrhage.

[Surgical treatment of endocrine ophthalmopathy]. / Kirurgisk behandling av endokrin oftalmopati.

Thyroid ophthalmopathy is an inflammatory disorder of the extraocular muscles, orbital fat and orbital connective tissue that is most commonly seen in patients with Graves' hyperthyroidism. Inflammation is accompanied by deposition of extracellular matrix components, in particular glycosaminoglycans. The increase in the volume of the orbital contents may lead to periorbital swelling, extraocular muscle dysfunction, disfiguring proptosis, exposure keratitis, increased intraocular pressure and optic nerve compression. In many cases, surgical treatment is necessary for the rehabilitation of patients. In this report, we present a series of patients to illustrate relevant procedures and the results of surgical treatment in patients with thyroid ophthalmopathy. The records of all patients (66) with thyroid ophthalmopathy hospitalized in the Department of Ophthalmology, Haukeland University Hospital 1 April 1994-31 March 1998 were retrospectively evaluated. Orbital decompressions were performed in 43 patients (in 17 for compressive optic neuropathy), squint surgery in 13 patients, correction of eyelid retraction in 20 patients, and removal of excessive skin and fat from the eyelids in 11 patients. Average reduction of proptosis was 4 mm after lateral wall resection, and 6 mm after combined medial and lateral wall resection. Visual acuity improved in patients with compressive optic neuropathy to 6/6 or better in 18/20 eyes (postoperative data were not available for all patients), while that of the remaining two eyes was 6/9 and 6/24, respectively. Squint surgery was successful (no diplopia in primary or reading position) in eight patients after one procedure, and in four after two procedures. One patient has been scheduled for a third procedure due to a severe esotropia. In patients with thyroid ophthalmopathy, suboptimal treatment of the thyroid disorder may worsen the ophthalmopathy. 16 patients had their medication adjusted, ten were referred for thyroid surgery, and one for treatment with radioiodine. Treatment of patients with thyroid ophthalmopathy is a therapeutic challenge requiring close collaboration between different specialists. In severe cases, several surgical procedures may be needed. The complication rate is low, however, and for most patients the functional as well as the aesthetic situation is greatly improved.

Neural compressive symptoms appearing during steroid treatment in a patient with intracranial lipoma.

Intracranial lipoma is a rare condition, and it is usually asymptomatic. We describe a 67 year old woman who developed blurred vision, diplopia, left sided oculomotor palsy, and ipsilateral ptosis during steroid treatment for giant cell arteritis. These symptoms were considered to be associated with aggressive giant cell arteritis, and the steroid dose was raised. Surprisingly, the symptoms increased, and further examination revealed an intracranial lipoma situated in the Meckel's cave. During tapering of the steroids her symptoms gradually improved. This is the first report demonstrating that steroids may induce hypertrophy of the fat tissue in the intracranial lipoma, causing compression of the cranial nerves passing through the cavernous sinus thereby mimicking the ocular symptoms sometimes associated with aggressive giant cell arteritis.

Post-dural puncture related complications after diagnostic lumbar puncture, myelography and spinal anaesthesia.

OBJECTIVES: This study was conducted to investigate complications after dural puncture. MATERIAL AND METHODS: A 15 months' prospective observation study of routine clinical practice with dural puncture at a university hospital was conducted. Quincke spinal needles 0.90 to 1.0 mm O.D. (20-19 g) were used for diagnostic lumbar puncture, 0.70 mm O.D. (22 g) for myelography and 0.40 to 0.50 mm O.D. (27-25 g) for spinal anaesthesia. A questionnaire about post-puncture discomfort was given to the patients, to be returned after 1 week. RESULTS: Of 679 questionnaires 537 (79.1%) were returned. Discomfort was experienced by 53.8% of the patients, most often after diagnostic lumbar puncture and myelography. The difference in incidence of headache after diagnostic lumbar puncture and myelography compared with spinal anaesthesia were 27.9% (95% CI: 18.6 to 37.2) and 18.3% (95% CI: 9.1 to 27.5). CONCLUSION: Small diameter and atraumatic spinal needles will reduce patients' discomfort after dural puncture.

[Radiologic examination of patients with head injuries. Late sequelae of minor head injuries, a radiological challenge]. / Radiologiske undersøkelser ved hodeskader. Senfølger også etter lettere hodeskader er en radiologisk utfordring.

We give a brief summary of the use of computerized tomography and magnetic resonance imaging (MRI) in cases of cranial trauma. The authors advocate more extended use of MRI in this connection; even in less severe cases. The method is much more sensitive than computer tomography, and thus provides a sounder basis for diagnosis and treatment in patients suffering from late sequelae of cranial injuries.

Expanding cava septi pellucidi and cava vergae in children: report of three cases.

Three children with hydrocephalus and expanding cysts of the cavum septi pellucidi and cavum vergae are reported. In all the patients, the hydrocephalus was present before the persistent cava started to expand. The cava increased gradually, until they became cystic, but their growth did not affect the size of the ventricles. Two of the patients were treated with internal cystoventricular shunts, causing a prompt collapse of the cysts but no change in the concomitant hydrocephalus. In the third patient, the persistent cava started to expand only when a previously implanted ventriculoperitoneal shunt failed temporarily. The cyst disappeared when the shunt resumed its function. The possible mechanisms underlying the expansive growth of persistent cava are discussed. We propose the theory that the growth of the cava in our patients may be the result, rather than the cause, of the hydrocephalus.

Bilateral non-traumatic carotid cavernous sinus fistula with spontaneous closure.

A case of bilateral spontaneous carotid cavernous sinus fistula is presented. The diagnostic value of Doppler ultrasound examination is discussed, as well as therapeutic measurements, such as manual compression of the carotid artery and embolization treatment. The frequent spontaneous closure of these fistulas is emphasized, and a conservative attitude is recommended.