Time-of-flight magnetic resonance angiography in the follow-up of intracranial aneurysms treated with Guglielmi detachable coils.

The purpose of this study was to evaluate time-of-flight magnetic resonance angiography (MRA) in the follow-up of intracranial aneurysms treated with Guglielmi detachable coils (GDCs). From January 1998 to January 2002 27 MRA and intra-arterial digital subtraction angiography (IADSA) examinations were analyzed for residual aneurysms and arterial patency following GDC placement. A total number of 33 intracranial aneurysms was analyzed, including 18 located in the posterior circulation. The MRA analysis was based on source images in combination with maximum intensity projections. The IADSA was used as the reference standard. Two aneurysms were excluded from evaluation, because of susceptibility artefacts from other aneurysms, which were clipped. Sensitivity and positive predictive values of MRA in revealing residual aneurysms were, respectively, 89% and 80%. Specificity in ruling out remnant necks and residual flow around coils was, respectively, 91% and 97%, with a negative predictive value of, respectively, 95% and 100%. Specificity and negative predictive value of MRA for arterial occlusion were, respectively, 87% and 100% for the parent arteries and, respectively, 85% and 100% for the adjacent arteries. MRA is a reliable diagnostic tool in the follow-up of GDC treatment, and it may replace IADSA in excluding residual flow around coils and aneurysmal necks and in ruling out arterial occlusion.

Magnetic resonance angiography in the selection of patients suitable for neurosurgical intervention of ruptured intracranial aneurysms.

This study was aimed at establishing whether magnetic resonance angiography (MRA) can be applied to planning and performing surgery on ruptured intracranial aneurysms, especially in the early phase, without recourse to intra-arterial digital subtraction angiography (IA-DSA). From February 1998 to August 2001, in all patients presenting with a subarachnoid hemorrhage, MRA was performed first. A three-dimensional time-of-flight MRA protocol with T2-weighted coronal and axial images was used. If MRA demonstrated an aneurysm, surgery was undertaken. IA-DSA was limited to patients with negative or inconclusive MRA findings. We compared MRA images with operative findings in positive patients and with IA-DSA in negatives. IA-DSA was considered the gold standard when MRA findings were inconclusive. In this study, 205 consecutive patients (mean age 52.7 years, 69% women) were included. In 133 patients (64.9%) MRA demonstrated an aneurysm, directly followed by neurosurgical intervention. In 33 patients (16.1%) MRA findings were categorized as inconclusive. In 39 patients (19.0%) MRA results were negative. No false-negative ruptured aneurysms were selected by MRA. In only one patient surgical intervention was performed based on false-positive MRA findings. MRA can replace IA-DSA as a first diagnostic modality in the selection of patients suitable for surgical treatment of ruptured intracranial aneurysms.

Primary lateral sclerosis: clinical, neurophysiological, and magnetic resonance findings.

OBJECTIVE: To describe the clinical, neurophysiological, and MRI findings in 10 patients with primary lateral sclerosis (PLS). RESULTS: The course of the disease was very slowly progressive. Spasticity due to upper motor neuron dysfunction was the most prominent sign, but EMG showed slight lower motor neuron signs, such as a mixed pattern on maximal voluntary contraction and enlarged motor unit potentials. One patient had clinically mild lower motor neuron involvement. Central motor conduction times (CMCT) were more prolonged in PLS than is the case in ALS. Minor sensory signs were found on neurophysiological examination, comparable with those in ALS. In four patients serum creatine kinase activity was raised. On MRI cortical atrophy was seen, most pronounced in the precentral gyrus and expanding into the parietal-occipital region. CONCLUSIONS: PLS is a distinct clinical syndrome, part of the range of motor neuron diseases. Besides pronounced upper motor neuron symptoms, mild lower motor neuron symptoms can also be found, as well as (subclinical) sensory symptoms. PLS can be distinguished from ALS by its slow clinical course, a severely prolonged MEP, and a more extensive focal cortical atrophy.

[Embolization of skeletal metastases in patients with differentiated thyroid carcinoma]. / Embolisatie van skeletmetastasen bij patiënten met gedifferentieerd schildkliercarcinoom.

Treatment options in patients with bone metastases of differentiated thyroid carcinoma are limited and mostly aimed at palliation. Conventional treatment modalities are: radioiodine therapy, surgery or external irradiation. A lesser known option is selective embolization of tumour metastases. During selective catheterization of the arteries that feed the metastases embolization material (e.g. polyvinyl alcohol particles) is injected into the local vasculature under radiographic control. The embolization is immediately evaluated angiographically. This therapy was used in three patients with differentiated thyroid carcinoma, a 60-year-old man suffering from back ache, paresis and afterwards paralysis of the lower body parts with incontinence, and in two women aged 59 years (suffering from diplopia and a pelvic metastasis) and aged 27 years (suffering from neurological symptoms or pain of the right leg due to a pelvic metastasis). In all three the symptoms disappeared after the embolization and ensuing treatment with radioactive iodine. Due to recurrent increase in serum thyroglobulin concentration repeated re-embolization was necessary, but during a follow-up period of 3-5 years the palliation remained adequate. Selective embolization appears to be a safe and efficacious treatment, with good tolerability for the patient. Embolization alone or preferably preceded by radioiodine therapy may lead to decreased tumour progression and often gives rise to immediate relief of symptoms.

Embolization in combination with radioiodine therapy for bone metastases from differentiated thyroid carcinoma.

BACKGROUND: The outcome for patients with bone metastases from differentiated thyroid carcinoma is worse compared to the overall prognosis of patients with differentiated thyroid carcinoma. The aim of this study is to evaluate the effect of embolization with concomitant radioiodine treatment on the serum thyroglobulin (Tg) level, pain and neurological symptoms in patients with large bone metastases from differentiated thyroid carcinoma. PATIENTS AND METHODS: Five symptomatic patients, who presented with a large unresectable bone metastasis of differentiated thyroid carcinoma were treated with radioiodine and embolization. The effect of this combined treatment was compared to the effect of radioiodine without embolization in a previously treated control group of 6 patients. Serum Tg levels, pain and neurological symptoms were scored. Both groups were treated similarly with total thyroidectomy followed by ablation with 5.55 GBq 131I and a second dose of 5.55 GBq 131I three months later, except for embolization in the embolization group, which took place between the 2 radioiodine treatments. RESULTS: In the embolization group, serum Tg at the second 131I therapy had decreased by 88.7% (median, range: 77.1-99.3%), which was significantly more compared to the decrease of serum Tg in the control group (18.6%, range: -4.7-95%, P < 0.05). CT-scanning showed a median volume reduction of the metastasis after radioiodine treatment combined with embolization of 52.5% (range: 39-80%). Both strategies resulted in a rapid relief of pain and neurological symptoms. Embolization was not accompanied with severe complications. CONCLUSIONS: This preliminary study suggests that embolization of bone metastases of differentiated thyroid carcinoma in combination with radioiodine treatment results in a significant initial reduction of serum Tg level compared to radioiodine treatment alone. This suggests a beneficial reduction in tumour burden. In this patient category, embolization appears to be a safe and well tolerated procedure.

Computed tomography and magnetic resonance imaging in mild to moderate head injury: early and late imaging related to outcome.

Serial magnetic resonance imaging (MRI) and computed tomographic (CT) studies were performed in mild to moderate head injury to evaluate whether early and late imaging have additional value in predicting outcome in this category of patients. During 1-year follow-up of a series of 67 patients, a CT scan on admission was performed together with MRI studies within 1 to 3 months and 6 to 12 months after injury. With CT, intracranial lesions were seen in 62% of patients compared with 44% with early and 19% with late MRI, located predominantly in the frontal and temporal regions. More than half of the lesions revealed with CT resulted in focal atrophy on MRI. Outcome was found to be worse in patients with edema and lesions on CT. Likewise, abnormalities detected with MRI were associated with poor outcome scores. In multiple regression analysis, only lesions in the frontal regions detected with early MRI were found to be predictive of outcome. With late MRI, only focal atrophy in the frontotemporal regions was found to be predictive of outcome. The findings in this study suggests that MRI studies may be valuable for predicting long-term outcome in patients with mild to moderate HI.

The oculocerebrocutaneous (Delleman-Oorthuys) syndrome.

We describe two cases of the so-called oculocerebrocutaneous syndrome, also known as the Delleman-Oorthuys syndrome. Both patients had characteristic congenital anomalies of the orbit, central nervous system and skin. The ocular and cerebral lesions were studied with CT and MRI.

Positron emission tomography in primary brain tumours using cobalt-55.

Primary brain tumours are usually assessed by computed tomography (CT) and magnetic resonance imaging (MRI), sometimes in conjunction with positron emission tomography (PET). We used cobalt-55 (55Co) as a calcium (Ca) tracer to visualize decaying tumour tissue, based on the fact that Ca-influx is essential in both cell death and leukocyte activation. Net 55Co uptake may be the result of cell decay, leukocyte infiltration, (re)perfusion and the pharmacological profile of 55Co. Three patients with primary malignant brain tumours (first presentation) were studied with CT, MRI and Co-PET after the intravenous administration of 0.5 mCi 55Co. Histopathological diagnosis was obtained by biopsy or resection. Co-PET demonstrated each of the brain tumours and showed good topographical agreement with CT and MRI. Co-PET provided additional detail as to the site and size of the necrotic core and the perinecrotic rim of decaying tumour. The 55Co uptake indices varied between 2.6 and 5.3. 55Co demonstrated uptake in decaying tissue, irrespective of the integrity of the blood-brain barrier. Neither necrotic nor viable tumour tissue showed affinity for 55Co. Since 55Co is readily applicable to both PET and single photon emission tomography (SPET), differences in the uptake mechanism and functional significance of the 55Co tracer are discussed in relation to 201Tl SPET. We present a (limited) pilot series of three patients to forward the claim of this new functional technique in nuclear neurology.

Preoperative assessment of the portal vein and hepatic artery in children with end-stage liver disease: is selective angiography still necessary?

BACKGROUND: Selective angiography involves increased risk for children and may cause vascular complications. The aim of this study was to determine whether selective angiography is still necessary for viewing the portal vein and hepatic artery. METHODS: Doppler ultrasound, abdominal aortography, and selective angiography were performed and interpreted independently in 62 children (median age = 1 year 3 months), with end-stage liver disease, who were candidates for orthotopic liver transplantation. RESULTS: Selective angiography agreed with the Doppler ultrasound findings of patency, flow direction, and diameter of the extrahepatic portal vein in 84%, 73%, and 79% of the children, respectively. Important additional information was obtained from selective angiography in only five of the 62 children (8%). Selective angiography showed an anomaly of the hepatic artery in 21 of the 62 children (33%). In 18 out of these 21 children (85%), an anomaly of the hepatic artery was already visible on the abdominal aortogram. CONCLUSION: Selective angiography did not play any significant role in the detection of an anomaly of the hepatic artery and should only be done if the Doppler ultrasound findings of the portal vein are inconclusive or if abdominal aortography cannot provide reliable information about the hepatic artery. For the evaluation of the portal vein and hepatic artery, we recommend Doppler ultrasound and abdominal aortography, a less invasive angiographic procedure.

Hyperprolactinaemia is associated with a higher prevalence of pituitary-adrenal dysfunction in non-functioning pituitary macroadenoma.

In non-functioning pituitary macroadenoma (NFMA), hyperprolactinaemia (hyperPRL) is considered to be a sign of hypothalamic-pituitary dysregulation, but it is unknown whether hyperPRL is associated with an increased frequency of pituitary hormone deficiencies. Forty consecutive patients with histology-proven NFMA were studied and hyperPRL was defined as serum prolactin (PRL) > 200 mIU/l in men and > 600 mIU/l in women. The pituitary-adrenal axis was evaluated by measurement of urinary free cortisol (N = 38), peak cortisol to insulin-induced hypoglycaemia (IIH, N = 36) and to human corticotrophin-releasing hormone (hCRF, N = 40) and by urinary tetrahydrol 11-deoxycortisol (H4S, N = 39), plasma androstenedione increment (N = 39) and serum 11-deoxycortisol (N = 1) after metyrapone. Central hypothyroidism, gonadotrophin deficiency and growth hormone (GH) reserve were also assessed. Twenty patients had hyperPRL (serum PRL 331 (223-1120) mIU/l (median, range) in men and 932 (660-3927) mIU/l in women): urinary free cortisol excretion (p < 0.03) and peak serum cortisol in response to IIH (p < 0.02) were lower in hyperPRL than in normoPRL patients; peak serum cortisol after hCRF was not different between groups but occurred later in hyperPRL patients (at 60vs 30 min, p < 0.03); urinary H4S excretion and androstenedione response after metyrapone were lower in hyperPRL than in normoPRL patients (p < 0.05 for both): 60% of hyperPRL patients and 15% of normoPRL patients had an abnormal H4S response (p < 0.025): central hypothyroidism (overt + subclinical) was present in 74% of hyperPRL and in 60% of normoPRL patients (NS); 78% of hyperPRL and 55% of normoPRL patients had gonadotrophin deficiency (NS): growth hormone (GH) deficiency was present in 83% of hyperPRL and in 89% of normoPRL patients (NS); 73.3% of 75 evaluable pituitary hormone axes were abnormal in hyperPRL patients compared to 53.8% of 78 hormone axes in normoPRL patients (by metyrapone test to examine adrenal function, p < 0.025); and no significant differences in tumour grade and stage distribution were found between hyperPRL and normoPRL patients. It is concluded that hyper-prolactinaemia in NFMA is associated with a higher prevalence of pituitary-adrenal dysfunction, which is likely to be explained at least in part by functional hypothalamic-pituitary interruption.

Cobalt-55 positron emission tomography in traumatic brain injury: a pilot study.

Traumatic brain injury is usually assessed with the Glasgow coma scale (GCS), CT, or MRI. After such injury, the injured brain tissue is characterised by calcium mediated neuronal damage and inflammation. Positron emission tomography with the isotope cobalt-55 (Co-PET) as a calcium tracer enables imaging of affected tissue in traumatic brain injury. The aim was to determine whether additional information can be gained by Co-PET in the diagnosis of moderate traumatic brain injury and to assess any prognostic value of Co-PET. Five patients with recent moderately severe traumatic brain injury were studied. CT was performed on the day of admission, EEG within one week, and MRI and Co-PET within four weeks of injury. Clinical assessment included neurological examination, GCS, neuropsychological testing, and Glasgow outcome scale (GOS) after one year. Co-PET showed focal uptake that extended beyond the morphological abnormalities shown by MRI and CT, in brain regions that were actually diagnosed with EEG. Thus Co-PET is potentially useful for diagnostic localisation of both structural and functional abnormalities in moderate traumatic brain injury.

Cobalt-55 positron emission tomography in relapsing-progressive multiple sclerosis.

Multiple sclerosis (MS) is an immune-mediated disease of the white matter in the brain that can have a progressive course. However, the progression of relapsing-remitting (RR) MS into relapsing-progressive (RP) MS might represent a more fundamental change in disease activity, i.e. decay of vulnerable neurons and oligodendrocytes. In RP-MS, this may imply that the major loss of brain tissue structure is caused by a combination of demyelination and cellular loss, both of which are likely to cause disability in MS. We used the PET isotope cobalt-55 (Co) as a calcium (Ca) tracer to visualize brain tissue damage, based on the fact that Ca influx is essential in both cell death and T-lymphocyte activation in MS. The aim of this study was to determine whether Co-PET detects any RP-MS lesions and, if so, to assess any correlation with the progression rate (PR) of the disease and with MS lesions as detected by MRI. Seven RP-MS patients (Poser) with EDSS > 4.0 (Kurtzke) and 7 healthy controls underwent MRI (Miller, Barkhof) and Co-PET. Comparison of both image modalities was made by merging. Co-PET lesion frequency was assessed and correlated with the PR of the disease. Co-PET demonstrated significantly more lesions in the MS brain than in the healthy brain, both periventricular and cortical. Every single MRI lesion could be retrieved as a Co-PET lesion. The Co-PET lesion frequency correlated significantly with PR. Our pilot study possibly suggests Co-PET as a tool in estimating disease activity in RP-MS.(ABSTRACT TRUNCATED AT 250 WORDS)

Correlation between magnetic resonance imaging and clinical parameters in multiple sclerosis.

In this study, the course of 60 consecutive multiple sclerosis patients (relapsing-remitting (RR), relapsing-progressive (RP), primary-progressive (PP)) was compared with the number and mean size of the lesions as well as the total load of the lesions as shown on magnetic resonance imaging (MRI). Significant differences were found between RR and RP patients in total load and number of lesions. Between RR and PP patients statistical significant differences were found in total load, number and size of the lesions when correlated with EDSS. Between RP and PP patients statistical differences were found in total load and size of the lesions on MRI. Patients with a relapsing course of the MS (RR or RP) had a higher total load and size of the lesions than PP patients. The total load, number and size of the lesions corrected for EDSS were also lower compared to relapsing patients. Factor analysis showed a correlation between clinical progression rate and progression rate of MRI abnormalities. No correlation between EDSS and total load of MRI lesions could be found. In conclusion, this study confirms the results of previous studies of differences between MRI scans of patients with a different course of MS.

On the principles underlying the diagnosis of brain tumours--a survey article.

A survey is given of the principles underlying the diagnosis of brain tumours. Traditionally diagnosis and localization of brain tumours have been based upon morphological criteria. Currently unsurpassed levels in imaging of anatomical details and topographical relations by the techniques of computed tomography (CT) and magnetic resonance imaging (MRI) have been achieved. The techniques of positron emission tomography (PET) and of magnetic resonance spectroscopy (MRS), which depict also metabolic and blood flow aspects, provide a refinement of our knowledge on the metabolism, structure and pathophysiological relations of a tumour to the surrounding parenchyma. Recent advances in the recording of function-related changes of the cerebral electro-magnetic field allow a better definition of critical functional areas.

Doppler ultrasound and angiography of the vasculature of the liver in children after orthotopic liver transplantation: a prospective study.

Despite the availability of Doppler ultrasound, angiography still forms part of the protocol for evaluating children after orthotopic liver transplantation (OLT) at our department. To investigate whether Doppler ultrasound is a reliable method for evaluating the patency of the hepatic artery, portal vein, inferior vena cava, and the anastomotic site of the portal vein in children after OLT, we performed a prospective study in which Doppler ultrasound was compared with angiography in 38 children with 40 transplants (ten examinations on clinical demand and 49 examinations according to protocol). Good correlation was found in relation to demonstrating a patent hepatic artery (sensitivity 96% and specificity 100%). Two false-negative Doppler ultrasound results were attributable to technical difficulties and rejection. For evaluating the patency of the portal vein, Doppler ultrasound agreed with angiography in 58 of the 59 examinations (98%). The one and only false-positive angiography result was explained by inadequate opacification. Doppler ultrasound visualized stenosis of the portal vein three times more often than angiography. In seven children, Doppler ultrasound findings suspicious of pathology of the inferior vena cava were confirmed using cavography or surgery. Doppler ultrasound proved to be a reliable technique for evaluating the patency of the hepatic artery, inferior vena cava, and portal vein and the anastomotic site of the portal vein.

Improved gas exchange after pneumonectomy in an adult with incomplete pulmonary vein atresia.

Atresia of the pulmonary veins of the left lung and the right upper lobe with moderate pulmonary hypertension was diagnosed in a 20 year old man presenting with exertional dyspnoea and haemoptysis. After left pneumonectomy gas exchange appeared to have improved. This was shown by improved arterial oxygen pressures during all steps of exercise in a cycle ergometer test in comparison with values obtained before surgery. This improvement could be entirely attributed to a decrease in physiological dead space ventilation.

Visualization of damaged brain tissue after ischemic stroke with cobalt-55 positron emission tomography.

UNLABELLED: In animal experiments, the radionuclide 55Co2+ has been shown to accumulate in degenerating cerebral tissue similar to Ca2+. METHODS: The potential role of 55Co2+ for in vivo brain PET imaging was investigated in four patients after ischemic stroke. RESULTS: PET showed uptake of 55Co2+ in damaged brain tissue irrespective of blood-brain barrier integrity, as affirmed by CT and MRI. CONCLUSION: Our preliminary results indicate that 55CoCl2 may prove to be a useful and relatively inexpensive PET radiopharmaceutical for visualization of degenerative processes in brain tissue.