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H Säveland

Publications and source records attributed to H Säveland.

At least 19 recordsLinked to original sources
PubMed2006

Endovascular treatment of intracerebral arteriovenous malformations: procedural safety, complications, and results evaluated by MR imaging, including diffusion and perfusion imaging.

BACKGROUND AND PURPOSE: Endovascular embolization is an increasingly common method to treat intracerebral arteriovenous malformations (AVM). To date, however, published data are rather scarce, especially with regard to true procedure-related complications and their causes. The purpose of our study was to evaluate treatment safety and correlate anatomic results with clinical outcome by using MR imaging, including diffusion-weighted (DWI) and perfusion imaging (PI). METHODS: We performed 50 endovascular procedures in 21 patients. Most AVMs were supratentorial, Spetzler-Martin grades II-IV. MR imaging was scheduled within 1 week before and 3 days after each treatment. MR imaging findings were correlated to digital subtraction angiography, procedure reports, and the clinical course. Outcome was graded according to the modified Rankin scale (mRS) 3-6 months after treatment. RESULTS: In this study, 104 MR imaging examinations were performed; mean interval between the endovascular procedure and posttreatment MR imaging was 28 hours. Nine adverse events occurred in 7 patients during 8 procedures (16%), one causing a permanent deficit. New lesions were noted on MR imaging after 22/50 procedures. Ischemic lesions in 22% of the procedures, frequently located perinidally. Most lesions were small, frequently asymptomatic, and reversible (18/23). Four hematomas were found. Subacute hemorrhages developed from a vasogenic edema on 2 occasions. New lesions, including hematomas, developed between treatments in 4 patients, mainly because of progressive occlusion of the nidus or draining veins. PI overestimated the AVM nidus on most occasions, and transient worsening of the PI pattern was noted in 2 patients. Treatment-related mortality and morbidity were 0% and 14.2%, respectively (mRS 1-2). CONCLUSIONS: Endovascular procedures are rather safe but are associated with more ischemic events and followed by less hemodynamic disturbances than previously understood. Adverse procedural events and new MR imaging lesions were generally asymptomatic and most often transient, if symptomatic. Most lesions would not have been verified without MR imaging. DWI and PI were most useful to detect and understand the cause of various complications. The most clinically important complications were caused by late venous occlusions.

Adult↗
PubMed2005

Diffusion and perfusion MRI in patients with ruptured and unruptured intracranial aneurysms treated by endovascular coiling: complications, procedural results, MR findings and clinical outcome.

Our purpose was to evaluate treatment safety as well as complications frequency and management in endovascular coiling of intracerebral aneurysms using MR diffusion and perfusion imaging. In this prospective study, 77 MR examinations were performed in conjunction with 43 procedures in 40 patients, 14 patients presented with ruptured and 26 with unruptured aneurysms. Mean time interval between treatment and post-procedure MRI was 29 and 25 h for the ruptured and unruptured aneurysm group, respectively. Peri-procedural complications, including five major events and five minor transient events, occurred in 10/43 procedures (23%), necessitating thrombolytic therapy in two patients and angioplasty in one, all three within the unruptured aneurysm group. Fifty-one new lesions were found on post-treatment DWI and 47 of them were regarded as of ischemic origin. Most lesions were small (<3 mm), ipsilateral to the treated aneurysm and asymptomatic (37/40 patients). Sixty-seven percent of the lesions were found in the ruptured and 33% in the unruptured aneurysm group. The ischemic lesions did occur more frequently in patients treated for aneurysm of large neck size and according to the remodelling technique. The overall morbidity and mortality rates were 14.6 and 7.3% whereas morbidity and mortality rates related to the technique were only 2.6 and 0%, respectively. Silent embolism seems to be more common than clinically evident and partially related to patient presentation, heparinazation and treatment strategy. The capability to depict early complications and analyse their potential causes by using MR with DWI has been of great importance in our modification and improvement of therapeutic protocols, evaluations and strategies.

Adult↗
PubMed2004

Selective diagnostic cervical nerve root block--correlation with clinical symptoms and MRI-pathology.

BACKGROUND: The aim of this study is to describe the method of a cervical selective diagnostic nerve root block (SNRB) technique and assess its ability to correlate clinical symptoms with MRI findings in patients with cervical radicular pain and a single level degenerative disease. METHODS: Twenty consecutive patients with cervical radiculopathy and correlating single level MRI pathology were studied. All patients underwent clinical investigation and neck and arm pain measurement with visual analog scales (VAS). The last 10 consecutive patients also underwent provocation with active neck motion when arm and neck pain were measured. They all underwent SNRB and 1 ml local-anesthesia (Mepivacaine 10 mg/ml) was injected, with the aid of fluoroscopy, close to the nerve-root. The VAS estimation and clinical investigation including provocation were repeated 30 minutes after the block. Criteria for a positive block response are a significant subjective pain reduction and at least 50% VAS pain reduction in the arm. FINDINGS: For the whole group mean VAS arm pain reductions were 86% and mean VAS neck pain reductions were 65%. When the results from the provocation were added all patients had a positive block. Eighteen were operated on by an anterior procedure and all 18 were free from radicular pain at follow up. INTERPRETATION: The block procedure seems relevant for revealing a relationship between radiological pathology and clinical symptoms and signs.

Adult↗
PubMed2004

Fatigue after aneurysmal subarachnoid hemorrhage evaluated by pituitary function and 3D-CBF.

OBJECTIVE: The reason for longstanding fatigue following aneurysmal subarachnoidal hemorrhage (SAH) is still not clarified. The bleed from supratentorial aneurysms is often in the vicinity of the hypothalamus and pituitary gland making an endocrine dysfunction plausible. METHODS: Ten patients with post-SAH fatigue were investigated with 3D-CBF (SPECT) and underwent an evaluation of the pituitary function. RESULTS: Five had normal pituitary function. Disturbances in the gonadotropin function was detected in three patients and suspected in two. The mean insulin-like growth factor I (IGF-I) value of the patients was in the lower part of the reference range. In the patients with endocrine dysfunction, the 3D-CBF was pathologic in the central structures of the basal region. CONCLUSIONS: The present results indicate that an aneurysmal SAH may result in partially impaired pituitary capacity. This deficit may contribute to fatigue after aneurysmal SAH, but cannot solely explain this disorder. SPECT identified regional tissue damage in the patients with pituitary dysfunction after SAH.

Adult↗
PubMed2002

Effects of iso- and hypervolemic hemodilution on regional cerebral blood flow and oxygen delivery for patients with vasospasm after aneurysmal subarachnoid hemorrhage.

BACKGROUND: Arterial vasospasm after subarachnoid hemorrhage may cause cerebral ischemia. Treatment with hemodilution, reducing blood viscosity, and hypervolemia, increasing cardiac performance and distending the vasospastic artery, are clinically established methods to improve blood flow through the vasospastic arterial bed. METHOD: Eight patients with transcranial Doppler verified vasospasm after subarachnoid hemorrhage were investigated with global (two-dimensional (133)Xenon) and regional (three-dimensional (99 m)Tc-HMPAO) cerebral blood flow (CBF) measurements, before and after 1/iso- and 2/hypervolemic hemodilution. Hematocrit was reduced to 0.28 from 0.36. Hypervolemia was achieved by increasing blood volume by 1100 ml. FINDINGS: Isovolemic hemodilution increased global cerebral blood flow from 52.25+/-10.12 to 58.56+/-11.73 ml * 100 g(-1) * min(-1) (p<0.05), but after hypervolemic hemodilution CBF returned to 51.38+/-11.34 ml * 100 g(-1) * min(-1). Global cerebral delivery rate of oxygen (CDRO(2)) decreased from 7.94+/-1.92 to 6.98+/-1.66 ml * 100 g(-1) * min(-1) (p<0.001) during isovolemic hemodilution and remained reduced, 6.77+/-1.60 ml * 100 g(-1) * min(-1) (p<0.001), after the hypervolemic hemodilution. As a test of the hemodilution effect on regional CDRO(2) an ischemic threshold was defined as the maximal amount of oxygen transported by a CBF of 10 ml * 100 g(-1) * min(-1) at a Hb 140 g/l which corresponds to a CDRO(2) of 1.83 ml * 100 g(-1) * min(-1). The brain volume with a CDRO(2) exceeding the ichemic threshold was 1300+/-236 ml before intervention. After isovolemic hemodilution the non-ischemic brain volume was reduced to 1206+/-341 (p<0,003). After hypervolemic hemodilution the non-ischemic brain volume remained reduced at 1228+/-347 ml (p<0.05). INTERPRETATION: The present study of controlled isovolemic hemodilution demonstrated increased global CBF, but there was a pronounced reduction in oxygen delivery capacity. Both CBF and CDRO(2) remained decreased during further hypervolemic hemodilution. We conclude that hemodilution to hematocrit 0.28 is not beneficial for patients with cerebral vasospasm after SAH.

Adult↗
PubMed2000

Cervical spine surgery in rheumatoid arthritis. A Swedish nation-wide registration of 83 patients.

OBJECTIVE: To investigate diagnostic methods, surgical methods and indications, early complications and short term outcome of cervical spine surgery for rheumatoid arthritis (RA). METHODS: A nation-wide registration of rheumatoid cervical spine surgery carried out in Sweden during 1993. RESULTS: Eighty-six (74 primary) procedures in 83 patients were reported from 11 hospitals. Pain was a more common indication for surgery than was neurologic impairment. C1-C2 instability or subluxation was present in 66/82, subaxial subluxations in 27/82 and atlantoaxial impaction in 10/82 procedures (data partly missing in one case). Indications for surgery and preoperative investigations were found to be reasonably uniform, but surgical methods and post-operative care varied between hospitals. Posterior fusion was performed in 76 patients. C1-C2 wiring with bone grafting was the most common procedure followed by occipito-cervical fusion with wires and bone cement. Subaxial cervical decompression without fusion, posterior fusion with onlay graft only, and carbon fiber grafts were used in a small number of patients. Total mortality was 5/83. The early complication rate was low, but 17 patients showed recurrent subluxation at follow-up at median 7 (1-17) months. Seven of them required reoperation in the same segment. CONCLUSION: The variation in treatment policy and number of operated patients in the different hospitals speak in favor for centralization of cervical spine surgery in RA. New methods for C1-C2-fusion need to be evaluated.

Adult↗
PubMed2000

Cognitive functioning and cerebrospinal fluid concentrations of neuropeptides for patients with good neurological outcomes after aneurysmal subarachnoid hemorrhage.

OBJECTIVE: Many patients exhibit cognitive disturbances after aneurysmal subarachnoid hemorrhage (SAH). Structural and functional neuroimaging has failed to demonstrate any correlation with these complaints. This study was performed to investigate whether neuropeptide concentrations in cerebrospinal fluid could be related to cognitive disturbances after SAH. METHODS: Lumbar cerebrospinal fluid was obtained, 3 to 6 months after surgery, from 17 patients who experienced good outcomes after aneurysmal SAH. The samples were analyzed for various neuropeptides using radioimmunoassays, and the peptide concentrations were evaluated in relation to scores on standardized neuropsychological tests. RESULTS: The neuropsychological test results were normal for eight individuals, whereas the remaining nine patients exhibited various degrees of cognitive impairment. There was no correlation between the concentrations of arginine vasopressin or neuropeptide Y and test performance. However, significant correlations between cognitive impairment and elevated levels of beta-endorphins (P = 0.02), corticotropin-releasing factor (P = 0.004), and delta sleep-inducing peptide (P = 0.045) were noted. CONCLUSION: Patients with cognitive impairments after aneurysmal SAH exhibited higher cerebrospinal fluid concentrations of endorphins, corticotropin-releasing factor, and delta sleep-inducing peptide than did those with normal capacity. This is probably attributable to diffuse derangement of transmitter release in the brain, resulting from the insult or ensuing complications, although a secondary increase in corticotropin-releasing factor concentrations caused by increased stress during the testing because of reduced cognitive capacity cannot be excluded.

Adult↗
PubMed2000

Incidence of intracerebral and subarachnoid haemorrhage in southern Sweden.

OBJECTIVES: Spontaneous intracranial haemorrhage-that is, mainly subarachnoid haemorrhage (SAH) and primary intracerebral haemorrhage (PICH)-constitutes an important part of all strokes. As previous epidemiological studies have demonstrated highly variable incidence rates, we conducted a large prospective investigation of all haemorrhagic strokes during a 1 year period. METHODS: Twelve hospitals serving a defined population of 1.14 million in southern Sweden registered all cases with spontaneous intracranial haemorrhage, including those found dead outside hospitals, during 1996. All patients were examined with CT of the brain or underwent necropsy. Incidence rates adjusted to the Swedish population for age and sex, as well as location of haematoma and prevalence of risk factors were calculated. RESULTS: A total of 106 patients with SAH and 341 patients with PICH were identified. The annual incidence/100 000 was 10.0 (6.4 for men and 13.5 for women) for SAH and 28.4 (32.2 for men and 24.7 for women) for PICH when adjusted to the Swedish population. Subarachnoid haemorrhage affected twice as many women as men. The incidence of both types of haemorrhage increased with advancing age, but in particular, this was the case for supratentorial PICH. Lobar haematomas were the most common (51.6%) type of PICH. Among patients with PICH, 37% had hypertension, 41% other vascular disease, and 12% were on oral anticoagulation. Among patients with SAH, 28% had hypertension and 18% vascular disease before the haemorrhage but no one was on treatment with oral anticoagulation. CONCLUSIONS: The incidence of PICH was high, especially for the older age groups. PICH was, on average, three times as common as SAH. The study underscores the importance of PICH and SAH as significant stroke subgroups.

Adult↗
PubMed1999

Additional colloids have only a minor haemodilutive effect after surgery for aneurysmal subarachnoid haemorrhage.

Haemodilution is commonly used as prophylaxis, as well as treatment for cerebral ischaemia after aneurysmal subarachnoid haemorrhage (SAH). Thirty-six patients operated for aneurysmal SAH were evaluated retrospectively; 24 received haemodilutive therapy and 12 patients, as a control group, received no additional therapy. There was a 'spontaneous' drop in haematocrit by 22% in both groups, and a corresponding drop in haemoglobin by 23% in the treatment group and 19% in the non-haemodiluted group, during the first 4 days after the SAH. After the initial decrease the haematocrit remained stable between 0.28 and 0.33 until day 14 in both groups. The haemodilutive group had only a minor lower haematocrit level during days 8-12 as the additional fluid resulted in increased renal excretion. This minor difference was, however, significant (p < 0.02).

Adult↗
PubMed1999

Bedside detection of brain ischemia using intracerebral microdialysis: subarachnoid hemorrhage and delayed ischemic deterioration.

OBJECTIVE: Intracerebral microdialysis has been demonstrated to be a useful method for detection of brain ischemia in experimental models and in patients. We have applied new mobile microdialysate analysis equipment that allows a bedside comparison of changes in neurochemistry with the neurological status of the patient. Ten patients with severe aneurysmal subarachnoid hemorrhage (that is, with a high risk of vasospasm and a high risk of subsequent ischemic deficits) were selected. METHODS: Microdialysis catheters were inserted into the temporal and subfrontal cortex at the end of aneurysm surgery. Samples, collected hourly for 4 to 11 days, were analyzed immediately at the bedside for glucose, lactate, and glycerol and later for pyruvate and glutamate. The patients' neurological status was monitored constantly, and daily recordings of blood flow velocities were performed using transcranial Doppler sonography. RESULTS: Concentrations of the measured substances varied widely. Individual analyses revealed that patients with uneventful clinical courses generally demonstrated low and stable levels of the different metabolites, and those with signs of cerebral ischemia demonstrated various patterns of neurochemical changes. Lactate and glutamate seemed to be sensitive markers of impending ischemia, and increased glycerol levels were associated with severe ischemic deficits. Obtaining the microdialysis data directly at the bedside seemed to be of great advantage when relating the values to other clinical findings. CONCLUSION: Bedside intracerebral microdialysis monitoring of patients with subarachnoid hemorrhage and signs of delayed ischemia revealed dramatic changes in extracellular concentrations of glucose, lactate, and glycerol that could be directly correlated to the clinical status of the patients. These findings emphasize the potential of microdialysis in neurosurgical intensive care patients.

Adult↗
PubMed1999

OP-1 for cervical spine fusion: bridging bone in only 1 of 4 rheumatoid patients but prednisolone did not inhibit bone induction in rats.

We used OP-1 (also called BMP-7) on a collagen type-1 carrier in atlanto-axial posterior fusions to promote bony healing after wire fixation. 4 patients who had instability between the atlas and axis due to rheumatoid disease received the implants. The patients were examined with conventional radiography postoperatively at 2, 6 and 10 months. In 3 patients, no new bone formation was detectable. In 1 patient, new bone bridged the fusion site at 6 months. 3 patients were on chronic steroid treatment, including the patient in whom bone formation was detected. To determine whether steroid treatment could be responsible for the low rate of bone induction, 24 rats each received OP-1 implants in an abdominal muscle pouch. They were divided into 3 groups receiving saline, 0.1 or 1.0 mg/kg BW of prednisolone daily until they were killed 3 weeks postoperatively. Specimens were decalcified for histology and the amount of calcium in the decalcifying solution was measured. All groups showed ossicles induced by OP-1, and no effect of prednisolone was detected. Thus the failures in the patients may have causes other than prednisolone treatment.

Animals↗
PubMed1999

Cervical laminectomy without fusion in patients with rheumatoid arthritis.

OBJECT: The authors performed a prospective study to determine whether cervical laminectomy without simultaneous fusion results in spinal instability. METHODS: Because of clinical and radiographic signs of cord compression, 15 patients with rheumatoid arthritis (including one with Bechterew's disease) and severe involvement of the cervical spine underwent decompressive laminectomy without fusion performed on one or more levels. Preoperative flexion-extension radiographs demonstrated dislocation but no signs of instability at the level of cord compression. Clinical and radiological reexamination were performed twice at a median of 15 months (6-24 months) and 43 months (28-72 months) postoperatively. One patient developed severe vertical translocation 28 months after undergoing a C-1 laminectomy, which led to sudden tetraplegia. She required reoperation in which posterior fusion was performed. No signs of additional instability at the operated levels were found in the remaining 14 patients. In three patients increased but stable dislocation was demonstrated. The results of clinical examination were favorable in most patients, with improvement of neurological symptoms and less pain. CONCLUSIONS: The authors conclude that decompressive laminectomy in which the facet joints are preserved can be performed in the rheumatoid arthritis-affected cervical spine in selected patients in whom signs of cord compression are demonstrated, but in whom radiographic and preoperative signs of instability are not. Performing a simultaneous fusion procedure does not always appear necessary. Vertical translocation must be detected early, and if present, a C-1 laminectomy should be followed by occipitocervical fusion.

Adolescent↗
PubMed1998

Transcranial cerebral oximetry related to transcranial Doppler after aneurysmal subarachnoid haemorrhage.

Noninvasive methods for detecting cerebral artery vasospasm, still a serious complication following aneurysmal subarachnoid haemorrhage, are of vital interest. Up-to-date transcranial Doppler ultrasound (TCD) has proved to be sensitive in detecting vasospasm in the middle cerebral artery, but has less accuracy for other cerebral arteries. Transcranial cerebral oximetry (TCCO) is a new non-invasive technique which may increase the reliability for detecting cerebral ischaemia. The purpose of the present study was to evaluate a putative correlation between TCCO and TCD. We examined the two hemispheres in 14 patients with the aim of evaluating a proposed correlation between TCD and TCCO. Analysis of all absolute values (maximum TCD mFV and minimum TCCO saturation, respectively) in all series indicate a correlation between TCCO and TCD, p < 0.01, r = -0.62. All patients with TCD mean flow velocity > 120 cm/s also presented TCCO saturation < 60%. Conversely, all patients with normal TCCO saturation (> or = 63%) presented normal or moderately increased TCD velocities. In clinical neurosurgical practice it is of great interest if a true correlation between TCD and TCCO exists. The present results support the assumption that TCCO may enhance the reliability for detecting cerebral ischaemia after aneurysmal subarachnoid haemorrhage.

Aneurysm, Ruptured↗
PubMed1997

Fusion or stabilization alone for acute distractive flexion injuries in the mid to lower cervical spine?

Long-term pain problems and residual restricted mobility were evaluated for patients sustaining acute distractive flexion injuries to the cervical spine. To assess which of two alternative surgical approaches gives better long-term outcomes, 58 patients were studied, 29 in each group. The results of posterior wire stabilization without fusion according to Brandt were contrasted with those of the Cloward technique. We found significantly more late pain problems and restricted neck mobility in the group treated with wiring without fusion than in those managed with anterior fusion. We conclude that this continuing pain may be due to residual mobility in the damaged degenerated non-fused motion segment, and that the difference between the two groups may reflect the difference in the quality and rate of fusion achieved by the two surgical approaches.

Adolescent↗
PubMed1996

Increased levels of glutamate in patients with subarachnoid haemorrhage as measured by intracerebral microdialysis.

Cerebral ischemia associated with subarachnoid haemorrhage (SAH) may have severe consequences for neuronal function leading to reversible or permanent neurological deficits. The excitatory amino acid neurotransmitters, such as glutamate, have been shown to be of particular importance for ischemic neuronal damage. In seven patients who underwent early surgery for a ruptured intracranial aneurysm, microdialysis of glutamate was performed in order to monitor local metabolic changes in the medial temporal tall patients) and subfrontal cortex (four patients). The preliminary results indicate that: (i) extracellular glutamate concentrations may rise to very high levels after SAH and aneurysm surgery, (ii) the increased levels of excitatory amino acids correlate with the clinical course, and (iii) a rise in extracellular glutamate in one region is not necessarily paralleled with a rise in the other, as seen by the simultaneous sampling from two different vascular territories.

Adult↗
PubMed1996

SPECT with technetium-99m-HMPAO in relation to late cognitive outcome after surgery for ruptured cerebral aneurysms.

Fifteen patients with a good neurological outcome after aneurysmal SAH and surgery were collected prospectively. Six months after surgery neurological examination and a SPECT study for evaluation of the three dimensional CBF distribution as well as an extensive neuropsychological test were performed. In all patients with pathological SPECT findings the location of the reduced regional CBF correlated with the location of the ruptured aneurysm and/or side of surgical approach. The volume of the brain tissue with reduced rCBF showed a great variety, from 9-112 cm(3) (mean: 33 cm(3)). Similarly, the maximum flow reduction in the affected areas also varied considerably from 17-95% (mean: 39%). In general, the neuropsychological functioning of the patients post SAH was favourable. Seven individuals had a presumably normal neuropsychological appearance with respect to estimates of premorbid levels of functioning. Another four patients were slightly impaired and the remaining four were moderately affected. Only in five cases did the location of SPECT pathology and the site of neuropsychological impairment appear to coincide, whereas this was not the case in the remaining 10 patients. In general, the extent of SPECT pathology did not differ in the three neuropsychological outcome groups (normal, slight and moderate disability).

Adult↗