MR Imaging in Multiple Sclerosis: The Accuracy of 3D Double Inversion Recovery at 3 Tesla and the Potential for Single Sequence Imaging.

To compare the accuracy of a three dimensional, T2-weighted double inversion recovery (DIR) sequence with two dimensional fluid attenuated inversion recovery (FLAIR) and dual echo T2 (DE T2) sequences at 3 Tesla in the detection of intracranial demyelinating lesions in patients with known or suspected multiple sclerosis (MS), and to consider the appropriateness of a stand-alone DIR sequence in MS imaging. The studies of 98 patients who underwent imaging with DE T2, FLAIR and DIR sequences for known or suspected multiple sclerosis were retrospectively reviewed. In 42 cases, a diagnosis of MS had been clinically suspected. In the remaining 56 cases, a diagnosis of MS had been previously established. All patients were imaged on a 3T MRI unit. Coronal and sagittal FLAIR, axial DE T2, and three dimensional T2-weighted DIR sequences were utilised. Of the 42 patients with suspected multiple sclerosis, 11 demonstrated lesions characteristic of the disease. Demyelinating plaques were seen in all of the 56 patients with known MS. In all cases, all lesions seen on DE T2-or FLAIR sequences were visible and more conspicuous on the DIR sequence. In 22 of the 67 patients (33%) with demyelinating lesions, the DIR sequence showed additional lesions not visible on any of the other sequences. Additional detected lesions predominantly involved grey matter. At 3 Tesla, a T2 weighted, three dimensional DIR sequence is as accurate at detecting the presence of intracranial demyelinating lesions as two dimensional FLAIR and DE T2 sequences combined. A greater number of lesions were detected with the DIR sequence, and all lesions were more conspicuous. A single, stand alone DIR sequence may be considered appropriate for monitoring MS.

MRI of bilateral internal carotid artery agenesis.

Bilateral internal carotid artery (ICA) agenesis is rare. A patient presented with symptoms of a transient ischaemic attack. Magnetic resonance imaging with magnetic resonance angiography showed multiple foci of chronic cerebral ischaemic change and bilaterally absent ICA. Cerebral supply was derived from the posterior circulation. Differentiation has to be made between congenital agenesis/hypoplasia and acquired ICA occlusion. Computed tomography through the skull base showed the absence of the carotid canals bilaterally confirming congenital ICA agenesis.

Endovascular treatment of intracranial aneurysms with Guglielmi detachable coils: analysis of midterm angiographic and clinical outcomes.

BACKGROUND AND PURPOSE: The previous decade has witnessed increasing application of Guglielmi detachable coils (GDCs) for the treatment of intracranial aneurysms. However, the midterm angiographic and clinical outcomes are not well documented. We report here the angiographic and clinical outcomes of patients treated with GDCs over an 8-year period. METHODS: Between 1992 and 1998, 144 patients with 160 intracranial aneurysms were treated with GDCs. Clinical follow-up data were obtained from medical records, questionnaires, and telephone interviews. Angiographic studies were reviewed by 2 neuroradiologists to obtain consensus regarding the degree of aneurysm occlusion. RESULTS: Eighty-one patients had ruptured aneurysms; 63 had unruptured aneurysms. Technical success was achieved in 91% of patients, with complete aneurysm occlusion in 46%, neck remnants in 16%, and residual body filling in 38%. Angiographic follow-up revealed that residual body filling in some aneurysms was resolved, small neck remnants were stable, and the recanalization rate decreased with time. All 63 patients with unruptured aneurysms were discharged from hospital with independent clinical status (Glasgow Outcome Score, 1 or 2). For patients with ruptured aneurysms, discharge clinical status correlated with the Hunt & Hess clinical grade at the time of treatment. Clinical follow-up for a minimum of 2 years was available in 98.5% of patients. Ninety-four percent of patients treated for unruptured aneurysms were independent at 2 years, and 82% of Hunt & Hess grade I to II patients were independent. CONCLUSIONS: Coil embolization is a safe and effective treatment for both ruptured and unruptured aneurysms. Increasing angiographic stability is demonstrated in treated aneurysms up to 3 years from coil embolization. Therefore, follow-up angiography until this time is advisable.

Multiple dural arteriovenous fistulas. Radiologic progression and endovascular cure. Case report.

SUMMARY: Dural arteriovenous fistulas are most probably acquired lesions. However, they have been rarely encountered de novo.We present a unique case of a 71-year-old woman who initially presented with right-sided dural arteriovenous fistula (DAVF), which spontaneously resolved after diagnostic arteriography. She later developed asymptomatic occlusion of the left transverse sinus. Five years after her initial presentation she developed left-sided pulse-synchronous tinnitus. MRA and catheter angiography showed a complex type IV DAVF between the left transverse sinus and multiple dural branches arising from both left and right external carotid arteries. The left transverse sinus was isolated from the torcula herophili, with stenosis of the sigmoid sinus. Extensive cortical venous drainage was demonstrated. Endovascular cure was effected by polyvinyl alcohol particle and absolute alcohol occlusion of the dominant dural supply, and transvenous coil occlusion of the left transverse sinus. The patient's symptoms resolved almost immediately. This unique case demonstrates that dural sinus occlusion and DAVFs may co-exist, but there may not be a causal relationship. It is likely that both DAVFs and sinus occlusion are manifestations of the same disease process characterised by a pro-thrombotic state and secondary angiogenesis. It is important to recognise that changes in symptomatology, even long after apparent disappearance of a lesion may indicate recurrence, and careful follow up is advocated.

Use of glycoprotein IIb-IIIa inhibitor for a thromboembolic complication during Guglielmi detachable coil treatment of an acutely ruptured aneurysm.

Thrombotic occlusion of the anterior communicating and right anterior cerebral arteries occurred during embolization of an acutely ruptured aneurysm of the anterior communicating artery. Traditional management, including superselective infusion of a fibrinolytic agent, was unsuccessful in reestablishing normal vessel patency. Therefore, an intravenous dose of abciximab was administered. Serial angiography showed that normal vessel patency was reestablished within 10 min. There were no adverse events related to abciximab administration, and the patient recovered from the procedure without neurologic deficit.

Carotid arterial stent placement: results and follow-up in 53 patients.

PURPOSE: To describe the results, complications, and follow-up data after stent placement for occlusive internal carotid arterial disease and to compare the results with those in the literature. MATERIALS AND METHODS: Carotid arterial stent placement was attempted in 57 arteries in 53 patients. Thirty-six (68%) of 53 patients were symptomatic. Forty-two (79%) of 53 patients had one to three clinically important comorbidities and were considered at high risk. All patients underwent pre- and postprocedural independent neurologic examinations. Follow-up consisted of serial duplex ultrasonography and clinical assessment. RESULTS: The immediate technical success rate of stent deployment was 97%. Periprocedurally, three (three [5%] of 57 interventions) transient ischemic attacks and three (three [5%] of 57 interventions) minor strokes occurred. Two deaths occurred in the first 30 days (one myocardial infarction, one renal failure). One ipsilateral major stroke occurred 3 weeks after the procedure. The 30-day ipsilateral major stroke and death rate was 5% (three of 57 interventions). At 30 days, one of three patients with minor stroke had mild residual dysphasia. Treatment remained clinically successful in 48 (96%) of 50 patients. The restenosis rate was 4% (two patients). CONCLUSION: Carotid arterial stent placement in a high-risk population has morbidity and mortality rates comparable to those of carotid endarterectomy in a lower risk population. Carotid arterial stent placement can be performed with a low restenosis rate.

Delayed aneurysm rerupture following total endovascular occlusion.

Endovascular coiling is a well established technique for the treatment of selected intracranial aneurysms, but its long-term efficacy, including the rate of rehaemorrhage from treated lesions, remains to be clearly determined. We report a case in which the rerupture of a small aneurysm occurred 12 months after embolization, despite angiographic occlusion on immediate post-procedural and 6-month check angiography.

Acute spontaneous spinal subdural haematoma: MRI features.

We present MRI findings in three patients with acute spontaneous subdural haematomas of the spine. Acute haematomas (1-3 days) were isointense or gave slightly high signal on T1-and heterogeneous signal on T2-weighted images. MRI precisely defined the level and extent of the haematoma preoperatively. The MRI was prospectively correctly interpreted as acute subdural haematomas in all patients. As a specific, noninvasive modality, MRI is the preferred imaging technique in this rare clinical entity.

Craniofacial mucormycosis following assault: an unusual presentation of an unusual disease.

A case of craniofacial mucormycosis following assault is discussed. A female diabetic developed peri-orbital cellulitis adjacent to a scalp wound which progressed to a necrotizing fasciitis. This did not respond to treatment. Subsequently the patient developed a hemiparesis, with CT imaging showing peri-orbital and paranasal sinus inflammatory changes, evidence of cavernous sinus invasion and development of a middle cerebral artery territory infarction. The patient died shortly afterwards. The imaging findings and their relationship to the pathological spread of mucor infection are discussed.

Vertebral synovial osteochondromatosis with compressive myelopathy.

STUDY DESIGN: A case report of vertebral synovial osteochondromatosis with compressive myelopathy. OBJECTIVES: To describe the clinical, radiologic, and histopathologic features of vertebral facet synovial osteochondromatosis with compressive myelopathy. SUMMARY OF BACKGROUND DATA: There has been only one previously reported case of synovial osteochondromatosis affecting the vertebral facet joint and no previous report of associated compressive myelopathy. METHODS: The case history, radiology, surgical findings, and histopathology are reviewed. RESULTS: Vertebral facet synovial osteochondromatosis is a potential and readily manageable cause of spinal cord compression. CONCLUSIONS: Synovial osteochondromatosis of the vertebral facet joint should be considered as a cause of compressive myelopathy.

Resolution of third nerve paresis after endovascular management of aneurysms of the posterior communicating artery.

The effect of endovascular treatment on the recovery of neural function in patients with third nerve palsy caused by an aneurysm of the posterior communicating artery is poorly documented. We report three cases in which third nerve paresis resolved completely within 2 to 3 weeks of endovascular occlusion of a posterior communicating artery aneurysm.

Transarterial platinum coil occlusion of ruptured intracranial aneurysms: results in 51 patients.

Fifty-one patients with subarachnoid haemorrhage (SAH) due to ruptured intracranial aneurysm have been treated by the Guglielmi detachable platinum coil (GDC) treatment method; 36 patients within 28 days of the ictus. There was total body occlusion in 64.8%, subtotal body occlusion in 24.1% and failed coil placement in 11.1%. Technical success rates were highest in aneurysms with neck sizes up to 4 mm (75% total occlusion) and aneurysms smaller than 10 mm largest diameter (72.5% total occlusion). At discharge from primary care, there were 62.7% without deficit rising to 74.5% at follow-up assessment. Four patients are dead and one disabled (9.8%). Patient clinical outcomes relate most closely to Hunt and Hess grade at time of definitive treatment. Higher initial grades and poorer clinical outcomes are concentrated in patients treated in the first 14 days. The incidence of procedure related thrombo-embolic events has fallen from 20% in the first 30 patients to 4.8% in the next 21. Rebleeding during GDC procedures occurred in 20.6% of patients treated 1-14 days post SAH.

Thoracolumbar disc degeneration in young fast bowlers in cricket: a follow-up study.

OBJECTIVE: To determine the progression of thoracolumbar disc degeneration in young fast bowlers in cricket. DESIGN: Prospective fast bowling technique and MRI follow-up study. BACKGROUND: Previous studies on high-performance young fast bowlers have found that lumbar spine pathology was related to the mixed bowling technique. METHODS: Nineteen young male fast bowlers (mean age 13.6 years) underwent MRI scans to detect the presence of intervertebral disc abnormalities. Subjects were also filmed laterally (200 Hz) and from directly above (100 Hz) whilst bowling two maximum velocity deliveries (session 1). Subjects were tested using an identical methodology 2.7 years later (session 2). RESULTS: At session 1, the incidence of thoracolumbar disc degeneration was 21%; however, at session 2, the incidence significantly (P = 0.008) increased to 58%. Furthermore the increase in the incidence of back pain between session 1 and session 2 was also significant (P = 0.002). The progression of disc degeneration was found to be significantly (P = 0.015) related to the group of fast bowlers who utilized the mixed technique during both session 1 and 2 when compared to those who used this technique during one session only. CONCLUSIONS: Thoracolumbar disc degeneration and back pain increase significantly during the time period examined in this study. Further, bowlers who utilize the mixed bowling technique stand a greater chance of developing degenerative changes of the spine.

Spontaneous polymerisation of cyanoacrylate/lipiodol mixtures causing failed embolisation. Laboratory studies.

SUMMARY: In vitro experiments to investigate spontaneous polymerisation of n-butyl-2-cyanoacrylate when mixed with non ionic oily contrast medium are reported. The results suggest an interaction between the mixture components which is unique to one particular batch of Lipiodol Ultrafluid and Histoacryl n butyl cyanoacrylate. The interaction cannot be reproduced with other batches of Lipiodol Ultrafluid nor with an alternative preparation of n-butyl-2-cyanoacrylate. Implications for the use of the materials in neuro-interventional practice are discussed.

Cost versus efficacy of magnetic resonance imaging.

Magnetic resonance imaging offers new and improved diagnostic capabilities in all body parts and organ systems. Examinations can be quicker, safer and less expensive than traditional radiological procedures. The cost/efficiency of magnetic resonance imaging is under active evaluation.

A review of magnetic resonance imaging in spinal trauma.

One hundred and ninety-five magnetic resonance (MR) images (1.5 Tesla) of 167 patients with neurological impairment following spinal trauma were reviewed. Acute cord injury produces central haemorrhagic necrosis that extends transversely and longitudinally with time and increased injury severity. Oedoma is more homogeneous, extensive and dominant in minimal lesions. Magnetic resonance appearances correlate with neurological status and outcome. Patients with MR evidence of cord blood had severe clinical lesions and failed to show useful clinical improvement. Patients with homogeneous 'oedema' improved to useful function. Lesion signal inhomogeneity relates to a worse prognosis. The clinical level correlates closely with cord blood or signal in homogeneity but imprecisely with homogeneous oedema. Disc herniations require differentiation from epidural blood and venous engorgement, which are prominent with bone displacement. Magnetic resonance is recommended in incomplete cord syndromes and in cord injuries with no apparent fracture, particularly if clinically deteriorating. Chronic injury consists of cavitation, extensive gliosis, cord atrophy and leptomeningeal fibrosis. Progressive myelopathy may result from cystic or non-cystic intramedullary lesions. Cord cysts are common and cyst fluid signal should closely follow cerebrospinal fluid. Turbulent cyst fluid motion is commoner in larger cysts and may predict those cysts more prone to propagate. Progressive syrinxes show typical appearances, usually with transverse septa. Atrophy and propagating syrinxes usually take years to develop. Leptomeningeal cysts and spinal stenosis caused by bone displacement and accelerated adjacent disc disease may cause late deterioration. In progressive myelopathy following injury, surgically drainable cysts are clearly differentiable from cord gliosis and atrophy.

Comparison of magnetic resonance imaging and computed tomographic discography in the assessment of lumbar disc degeneration.

Eighteen patients with chronic low back pain were studied with magnetic resonance imaging (MRI) and computed tomographic (CT) discography. Each study was classified as being normal, showing early disc degenerative changes including annular tear, showing established disc degeneration or disc herniation. There was comparable information in over 90% of the MRI studies when compared to CT discography, without reliance on pain provocation or carrying out an invasive procedure. The axial and sagittal T1 weighted images were used to exclude other causes of pain, such as foraminal stenosis and disc herniation. The mid-sagittal T2 weighted image used in this study was considered to be, in part, responsible for the underestimation of disc degeneration because it did not allow visualization of the lateral aspects of the discs.

Craniopharyngioma and the moustache sign.

Craniopharyngiomas are common suprasellar tumours but these are rarely associated with vasogenic oedema. Because the oedema extends into the optic tracts and optic radiations, a characteristic pattern is produced that resembles a moustache. The oedema is though to be due to leakage of craniopharyngioma contents. Such a case is presented in this communication.

The effect of magnetic resonance imaging in a teaching hospital on patient management.

An observational study was undertaken to obtain measures of the impact of magnetic resonance imaging (MRI) on diagnosis, patient management and patient outcome. A minimum data set at the time of examination was used for 1119 consecutive patients referred by specialists for MRI of the brain or spine. Three month follow up of 707 brain examinations and 235 spinal examinations was undertaken using a questionnaire on diagnosis and patient management. Magnetic resonance imaging made a dominant contribution to final diagnoses of neoplasia and vascular disorders, but was less significant for white matter disease. In a high proportion of cases other types of examination also influenced the final diagnosis. Magnetic resonance imaging affected patient management in a high proportion of spinal examinations and in cases of cerebral neoplasm, with lesser contributions to cases of cerebrovascular disorder and white matter disease. While MRI was considered superior to other imaging methods, which it could often replace, in practice it will form only one input to the diagnostic decision.