Biomedical subjects

S J Bakke

Publications and source records attributed to S J Bakke.

At least 19 recordsLinked to original sources

PubMed2005

Cerebral thrombotic microangiopathy and antiphospholipid antibodies in Aicardi-Goutieres syndrome--report of two sisters.

Cerebral thrombotic microangiopathy was found at autopsy in one of two sisters with Aicardi-Goutieres syndrome, whereas the other revealed increased serum levels of anticardiolipin IgG antibodies (measured only in the living sister); both typical features of systemic lupus erythematosus. These findings add support to the suggestion that Aicardi-Goutieres syndrome and systemic lupus erythematosus are closely related disorders in which dysregulated production of interferon-alpha might play a crucial role.

Antibodies, Antiphospholipid↗

PubMed2004

Reduced neuropsychological test performance in asymptomatic carotid stenosis: The Tromsø Study.

OBJECTIVE: To assess the relationship between asymptomatic carotid stenosis, neuropsychological test performance, and silent MRI lesions. METHODS: Performance on several neuropsychological tests was compared in 189 subjects with ultrasound-assessed carotid stenosis and 201 control subjects without carotid stenosis, recruited from a population health study. Subjects with a previous history of stroke were excluded. The test battery included tests of attention, psychomotor speed, memory, language, speed of information processing, motor functioning, intelligence, and depression. Sagittal T1-weighted and axial and coronal T2-weighted spin echo MRI was performed, and presence of MRI lesions (white matter hyperintensities, lacunar and cortical infarcts) was recorded. RESULTS: Subjects with carotid stenosis had significantly lower levels of performance in tests of attention, psychomotor speed, memory, and motor functioning, independent of MRI lesions. There were no significant differences in tests of speed of information processing, word association, or depression. Cortical infarcts and white matter hyperintensities were equally distributed among persons with and without carotid stenosis. Lacunar infarcts were more frequent in the stenosis group (p = 0.03). CONCLUSIONS: Carotid stenosis was associated with poorer neuropsychological performance. This could not be explained by a higher proportion of silent MRI lesions in persons with asymptomatic carotid stenosis, making it less likely that the cognitive impairment was caused by silent emboli.

Aged↗

PubMed2004

Emotional responses during unilateral amobarbital anesthesia: differential hemispheric contributions?

OBJECTIVES: To explore (1) effects of test and subject variables in determining euphoric and dysphoric responses during unilateral amobarbital anesthesia and (2) which cerebral areas contribute to the emotional responses. METHOD: Incidence of euphoric and dysphoric reactions during left- and right-sided amobarbital anesthesia of the internal carotid artery (ICA) and selective anesthesia of the middle cerebral (MCA) and the posterior cerebral (PCA) artery was recorded. The sample comprised 270 Norwegians (6-61 years), and a total of 562 injections were performed under conditions endeavoring to calm down the patients. RESULTS: The overall incidence of observed emotional responses during ICA anesthesia was 21.5%, euphoric reactions being about 10 times more frequent than dysphoric. The incidence of euphoric reactions, however, was not significantly higher under right- than under left-sided anesthesia, and dysphoric reactions were not more frequent under left- than under right-sided anesthesia. Indeed, 13 patients showed elevated mood under both right- and left-sided anesthesia. Anesthesia of the territories of ICA and MCA gave rise to similar results, while no cases of mood change were observed under selective PCA anesthesia. CONCLUSION: It is concluded that unilateral amobarbital anesthesia as such, irrespective of side, may trigger both euphoric and dysphoric responses. The relative frequency obtained is influenced importantly both by the emotional responsiveness of the subjects and the emotional climate of the test situation. Finally, it is suggested that brain regions supplied by the PCA contribute less to modulation of euphoric and dysphoric responses than those supplied by the MCA or the ICA.

Adolescent↗

PubMed2003

Brain cysts associated with mutation in the Aristaless related homeobox gene, ARX.

The novel Aristaless related homeobox gene, ARX, is widely expressed in the brain and is thought to play a key role in the regulation of brain development. Neurological phenotypes caused by ARX mutations have recently started to unfold. We describe a 72 year old man with X-linked mental retardation due to a 24 bp duplication mutation in exon 2 of the ARX gene. Cerebral MRI showed bilateral cystic-like cavities in both the cerebral and cerebellar hemispheres. No retraction or expansion in neighbouring parenchyma was observed, there was no history of acute neurological impairment, and no risk factors for cerebrovascular disease were found. The lesions appeared to be congenital and represented benign developmental cysts, possibly caused by the ARX mutation.

Aged↗

PubMed2002

MR angiography in the follow-up of coiled cerebral aneurysms after treatment with Guglielmi detachable coils.

PURPOSE: Intra-arterial digital subtraction angiography (DSA) has been considered the gold standard examination in the follow-up of patients treated with Guglielmi detachable coils (GDCs). However, DSA is an invasive and expensive investigation and results in exposure to ionising radiation to both patient and operator. The aim of this study was to compare MR angiography (MRA) with DSA with regard to patency of the occlusion of aneurysms following GDC treatment. MATERIAL AND METHODS: We performed 75 MRA and DSA examinations on 51 patients treated with GDCs. The examinations were performed 3-36 months after embolisation and the interval between MRA and DSA was less than 1 week. Hard copies of both studies were interpreted retrospectively and independently for residual flow within the aneurysm, residual aneurysmal neck, and parent and branch vessel flow. RESULTS: Patency status of parent and branch vessel flow was correctly identified with MRA in all patients except 1. The sensitivity of MRA in revealing residual flow within the aneurysm was 97%. The specificity in ruling out residual flow within the aneurysm was 91%. CONCLUSION: MRA may replace DSA in the long-term follow-up of coiled cerebral aneurysms. The initial follow-up examination should, however, include both modalities.

Angiography, Digital Subtraction↗

PubMed2001

[Usefulness of SPECT and MRI in the diagnosis of atypical parkinsonism].

BACKGROUND: Clinico-pathological studies have shown that only three out of four patients with parkinsonism have idiopathic Parkinson's disease. In patients with so-called Parkinson plus syndrome, the degeneration in the brain is more widespread and the variety of neurological signs greater than in Parkinson's disease. The differentiation of these syndromes from Parkinson's disease can be difficult. Single photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI) can be of value in the differential diagnosis of parkinsonism. MATERIAL AND METHODS: We present three patients with atypical parkinsonism in whom MRI and SPECT with beta-CIT and epidepride was performed in addition to the clinical evaluation. RESULTS: The three patients all had a rapidly developing symmetric akinetic-rigid syndrome that responded poorly to levodopa. MRI showed findings regarded as typical for multiple system atrophy in two patients, but only nonspecific findings in the third patient. SPECT with beta-CIT showed a pronounced bilateral and relatively symmetric reduction in the striatal dopaminergic activity in all patients. SPECT with epidepride showed a clearly reduced striatal D2-receptor binding bilaterally in only one of the patients. INTERPRETATION: In patients with atypical parkinsonism, MRI and SPECT with beta-CIT and epidepride can give valuable support to the clinical diagnosis of a Parkinson plus syndrome.

Diagnosis, Differential↗

PubMed2001

[Resection of malignant tumors involving the anterior cranial fossa].

BACKGROUND: The craniofacial approach has greatly facilitated resections of tumours involving the base of the anterior cranial fossa when compared to either the transcranial or transfacial approach alone. MATERIAL AND METHODS: This approach was used in 11 patients with malignant tumours localized to the ethmoid sinus, orbit and bone or soft tissue of the base of the anterior part of the skull. By combining a low frontal or frontolateral craniotomy with resection of the facial skull, en bloc resections were accomplished. A frontogaleal periostal flap or a muscle flap from the temporal muscle was used to replace resected bone and to seal the skull base. RESULTS: There were no peri- or postoperative deaths. One patient died due to local recurrence, one patient is alive with residual tumour six years after surgery, and one is reoperated due to local recurrence. In addition one patient developed recurrence of a previously treated tumour of the maxillary sinus. Two patients developed meningitis and one pneumocephalus postoperatively. One patient has partial loss of vision and two patients underwent dacryocystorhinostomy due to epiphora. INTERPRETATION: The planning and execution of this type of surgery requires close interaction in an interdisciplinary team, in particular between neurosurgeon and head and neck surgeon.

Adolescent↗

PubMed2001

[Choice of neuroradiological methods in ophthalmology--the eye and the lacrimal apparatus].

With improved imaging methods, the possibility of demonstrating pathological changes in the visual pathways has increased substantially. However, optimal evaluation of visual disorders requires familiarity with the anatomy and pathology of the visual pathways, and with the many advances in neuroimaging. The purpose of this article is to provide clinicians with a practical approach for selecting the most appropriate imaging modalities. Choice of technique is discussed with reference to anatomical regions rather than a complete list of diseases. Ophthalmoscopy reveals many intraocular abnormalities. Imaging studies help in cases where opaque media preclude a view of the fundus. In addition, imaging studies assist in confirming the extraocular extent of the lesion. The advantages and disadvantages of x-ray, computed tomography and magnetic resonance imaging are discussed and illustrated by examples.

Eye Diseases↗

PubMed2001

[Choice of neuroradiological methods in ophthalmology--the optic nerve, muscles of the eye and orbit].

Optimal imaging of the orbital structures presents a challenge. Images of this region may be disturbed by ocular movements, and orbital fat may prevent visualisation of the optic nerve and retrobulbar lesions. In this article, we intend to provide practical guidelines for the evaluation of orbital abnormalities, on the basis of our own experiences and a study of selected literature. Computed tomography (CT) and magnetic resonance imaging (MRI) are both useful for the detection and characterisation of orbital abnormality. However, for diagnostic work-up of the optic nerves, contrast-enhanced, fat-suppressed MRI best demonstrates the pattern and severity of optic nerve abnormality and allows assessment of the intracranial part of the optic nerves and associated intracranial abnormality. In the case of bony involvement, spiral CT imaging is the modality of choice. It is quick, inexpensive and allows multiplanar reconstruction. Not uncommonly, CT as well as MRI may be needed to characterise an orbital lesion.

Eye Diseases↗

PubMed2001

[Neuroradiological imaging of the 3rd, 4th and 6th cranial nerves].

The ocular motor cranial nerves (III, IV, VI) control the eye movements in a near association with the higher cortical areas. Clinically, the most common presentation of abnormal ocular motility is double vision. Identifying the cause of ocular nerve palsy can be difficult, and a large percentage of such cases still remains undiagnosed, even in a new era of neuroradiological techniques. Close co-operation between the clinician and the radiologist is necessary for the selection of the best imaging methods for the specific clinical problem, in order to set the aetiological and topological diagnosis. This article provides a practical review of advances in neuroimaging of the ocular motor nerves.

Abducens Nerve Diseases↗

PubMed2001

CTA in patients with acute subarachnoid haemorrhage. A comparative study with selective, digital angiography and blinded, independent review.

PURPOSE: Minimal- or non-invasive methods replacing intra-arterial digital subtraction angiography (IA-DSA) would be of great importance in patients suffering from acute subarachnoid haemorrhage (SAH). The aims of this study were to compare CTA with IA-DSA in patients with acute SAH, to compare CTA interpretations with those of blinded, independent reviewers and to evaluate improvement in CTA diagnostics after 1 year of experience with CTA. MATERIAL AND METHOD: During 2 years 162 patients with SAH underwent CTA as well as IA-DSA. Independent blinded review of 77 patients was performed for 1 year. RESULTS: Totally 144 aneurysms were demonstrated in 119 patients at IA-DSA, while 43 patients had normal intracranial arteries. Initially 131 aneurysms were detected at CTA while 2 normal, tortuous arteries were misinterpreted as aneurysms, giving a sensitivity of 91% and a specificity of 95%. At independent blinded review the observer agreement was 87% and the kappa value 0.68. CONCLUSION: CTA in SAH is of great value in demonstrating vascular anatomy and the exact size of an aneurysm. However, IA-DSA is still needed for diagnostic evaluation in aneurysms smaller than 5 mm in diameter, especially in those located near bony structures.

Acute Disease↗

PubMed2000

[Long-term survival following surgery and radiotherapy of brain tumors in childhood].

BACKGROUND: Brain tumours are seen in about one third of children with neoplastic disease. Treatment usually includes surgery and/or radiotherapy. Radiotherapy may have serious late effects, especially in children under the age of three; but is necessary for survival in children with medulloblastomas or high-grade gliomas. MATERIALS AND METHODS: We report ten and 20 years survival rates in 115 children with primary brain tumours (58 medulloblastoma, 14 high-grade gliomas, and 43 low-grade gliomas) operated at the National Hospital and given radiotherapy at the Norwegian Radium Hospital during the years 1970-1995. RESULTS: No patients with medulloblastomas or high-grade gliomas relapsed after ten years. Overall ten and 20 years survival in children treated with radiotherapy to tumour doses > 50 Gy for medulloblastoma was 51.5% and for high-grade gliomas 20%. Median survival for patients with low-grade gliomas was not reached at 20 years, but these patients were still at risk for late deaths. INTERPRETATION: Long-term survival in children with high-grade gliomas or medulloblastoma equals cure, while late relapses may occur in low-grade gliomas.

Adolescent↗

PubMed2000

Improving postoperative MR imaging of pituitary macroadenomas: comparison of full and reduced dose of gadopentetate dimeglumine.

The aim of this study was to evaluate the efficacy of contrast-medium (CM)-ehanced MR imaging of operated pituitary macroadenomas with reduced dose of gadopentetate dimeglumine. In a prospective study 18 patients were examined with coronal T1-weighted MR imaging prior to and following intravenous CM injections. Two sets of contrast-enhanced coronal images were obtained in each patient; the first set after 50% of the recommended dose of 0.1 mmol/kg body weight (b.w.) had been administered, and the second set immediately after additional CM had been given to make up a total dose of 0.1 mmol/kg b.w. The images were evaluated by three neuroradiologists. The SIPAP classification system was used to evaluate tumour extension, whereas tumour margin conspicuity was scored using an arbitrary scale of 1-5 (1 = indistinct, 5 = well defined). Signal intensity measurements obtained from the most enhancing part of the adenomas demonstrated increased enhancement with increased CM dose. Tumour delineation scores were significantly better on the reduced- and full-dose images than on pre-CM injection images, but, with one exception, tumour extension was identified as the same on all imaging sequences. Postoperative MR imaging of large macroadenoma residues can routinely be performed without intravenous CM. When CM is indicated a reduced dose of gadopentetate dimeglumine should provide sufficient diagnostic information.

Adenoma↗

PubMed2000

Intracerebral abscess caused by Nocardia otitidiscaviarum in a renal transplant patient--cured by evacuation plus antibiotic therapy.

We present a 50-year-old female who experienced generalized convulsion 3 months after a successful cadaveric renal transplantation. The first cerebral CT scan indicated cerebral frontal infarction. Repeat CT some days later revealed progressive lesions, and a highly malignant tumor or abscess was suspected. Antifungal and broad-spectrum antibacterial therapy was initiated. Cerebral MRI could not differentiate between these conditions, but a neutrophil granulocyte scan strongly suggested an infectious process. A stereotactic puncture of the frontal lobe was followed by temporary improvement. A severe progressive left-sided hemiparalysis gave indication for a craniotomy with evacuation of the abscess 9 days later. Culture of aspirated pus yielded growth of a gram-positive, rod-shaped bacterium, later identified as Nocardia otitidiscaviarum by sequencing the 16S rRNA. The patient was treated with meropenem plus rifampicin intravenously for 6 weeks followed by oral ciprofloxacin and rifampicin for 2 months. Due to pharmacokinetic interaction with rifampicin, the prednisolone dose was doubled, and the dose of tacrolimus had to be tripled for maintenance of adequate trough concentrations. Five months following cessation of antibiotic treatment, the patient has regained normal strength and function in her left-sided extremities and has a serum creatinine level of about 160 micromol/l (1.8 mg/dl).

Anti-Bacterial Agents↗

PubMed2000

Failure to confirm neurotoxic impairment using cerebral magnetic resonance imaging on solvent-exposed workers.

OBJECTIVES: The study aimed at assessing signs of nervous system impairment by cerebral magnetic resonance imaging (MRI) among workers with a history of long-term exposure to mixtures of organic solvents. METHODS: Thirty-six workers (mean age 44.1 years) with at least 10 (mean 23.9) years of occupational exposure to solvents and pair-matched referents with no former solvent exposure went through a blind, random-order investigation of cerebral MRI, performed with a 1.5-tesla scanner. RESULTS: Linear measurements of the MRI tomograms showed a slight tendency toward wider ventricles and broader cortical sulci in the reference group. Visual evaluation of the MRI by 2 experienced neuroradiologists showed no significant difference between the groups; however, there was substantial interobserver variability. CONCLUSIONS: The MRI findings of this study do not support the hypothesis that long-term low-level occupational exposure to organic solvents results in the development of brain atrophy, or specific MRI signal changes in the region of the basal ganglia and thalami.

Adult↗

PubMed1998

Varying impact of common carotid artery digital compression and internal carotid artery balloon test occlusion on cerebral hemodynamics.

BACKGROUND: The purpose of this study was to compare the cerebral hemodynamic changes brought about by common carotid artery (CCA) digital compression and angiographic internal carotid artery (ICA) balloon occlusion. METHODS: Bilateral transcranial Doppler ultrasonographic monitoring of the middle cerebral artery blood velocity (VMCA) was performed in 12 subjects with neck neoplasms or traumatic carotid-cavernous fistulas. The MCA pulsatility index (PIMCA) and hemodynamic tension (Uhem MCA) were calculated. RESULTS: Common carotid artery compression provoked the largest drop in ipsilateral VMCA, PIMCA, and Uhem MCA. Common carotid artery compression caused a steal of blood from the intra- to the extracranial circulation, with the discrepancy in hemodynamic findings between CCA and ICA test occlusions being dependent on the quantity of reversed ipsilateral ICA blood flow. CONCLUSION: If the carotid artery is to be sacrificed, permanent ICA closure is the procedure of choice with respect to the occurrence of cerebral ischemic lesions in patients with neck neoplasms and ICA flow reversal during CCA compression.

Adolescent↗

PubMed1997

[Perimesencephalic subarachnoid hemorrhage].

Acute, non-traumatic subarachnoid haemorrhage is usually caused by a ruptured aneurysm. This is a serious condition involving high mortality. Perimesencephalic haemorrhage has recently been identified as a clinical subset of subarachnoid haemorrhage. A pattern of haemorrhage predominantly limited to perimesencephalic cisterns on CT is highly predictive of a normal angiogram, and is connected with an excellent prognosis. We describe two patients with perimesencephalic haemorrhage.

Acute Disease↗

PubMed1997

[Hemangioma and vascular malformations. Diagnosis and treatment].

The authors discuss the dilemmas associated with diagnosis and treatment of haemangiomas and vascular malformations. The complexity of these conditions too often sends the patients wandering from one specialist to another in search of an optimal therapeutic approach. We have established a multidisciplinary team to facilitate interspecialty communication on diagnosis, natural history, and therapy.

Arteriovenous Malformations↗