Biomedical subjects

Göran Edner

Publications and source records attributed to Göran Edner.

4 recordsLinked to original sources

PubMed2006

Gamma knife surgery for dural arteriovenous shunts: 25 years of experience.

OBJECT: The aim of this study was to assess the clinical efficacy of gamma knife surgery (GKS) in the treatment of dural arteriovenous shunts (DAVSs). METHODS: From a database of more than 1600 patients with intracranial arteriovenous shunts that had been treated with GKS, the authors retrospectively and prospectively identified 53 patients with 58 DAVSs from the period between 1978 and 2003. Four patients were lost to follow-up evaluation and were excluded from the series. Thus, this study is based on the remaining 49 patients with 52 DAVSs. Thirty-six of the shunts drained into the cortical venous system, either directly or indirectly, and 22 of these were associated with intracranial hemorrhage on patient presentation. The mean prescription radiation dose was 22 Gy (range 10-28 Gy). All patients underwent a clinical follow-up examination. In 41 cases of DAVS a follow-up angiography study was performed. At the 2-year follow-up visit, 28 cases (68%) had angiographically proven obliteration of the shunt and in another 10 cases (24%) there was significant flow regression. Three shunts remained unchanged. There was one immediate minor complication related to the administration of radiation. Furthermore, one patient had a radiation-induced complication 10 years after treatment, although she recovered completely. There was one posterior fossa bleed 2 months after radiosurgery; a hematoma, as well as a lesion, was evacuated, and the patient recovered uneventfully. A second patient had an asymptomatic occipital hemorrhage approximately 6 months postradiosurgery. The clinical outcome after GKS was significantly better than that in patients with naturally progressing shunts (p < 0.01, chi-square test); figures on the latter have been reported previously. CONCLUSIONS: Gamma knife surgery is an effective treatment for DAVSs, with a low risk of complications. Major disadvantages of this therapy include the time elapsed before obliteration and the possibility that not all shunts will be obliterated. Cortical venous drainage from a DAVS, a risk factor for intracranial hemorrhage, is therefore a relative contraindication. Consequently, GKS can be used in the treatment of both benign DAVSs with subjectively intolerable bruit and aggressive DAVSs not responsive to endovascular treatment or surgery.

Central Nervous System Vascular Malformations↗

PubMed2003

Management of patients with brain arteriovenous malformations.

Arteriovenous malformations (AVMs) of the brain, which are probably genetically determined, are errors in the development of the vasculature that, together with the effects of blood flow, may lead to a focal arteriovenous shunt. Clinically, the adult patient may present with acute or chronic neurological symptoms-fixed or unstable-such as deficits, seizures or headache. Sometimes the lesion is an incidental finding. In about half of the patients, the revealing event is an intracranial haemorrhage. The prevalence of AVM in the western world is probably <0.01% and the detection rate is about one per 100,000 person-years. Most AVMs are revealed in patients 20-40 years of age. Therefore, the risk of developing neurological symptoms from an AVM, usually because of haemorrhage, increases with patient age. In the young adult population, AVMs are significant risk factors for hemorrhagic stroke. This risk increases with AVM volume and is higher in centrally located AVMs. Almost all patients with AVM are subjected to treatment, either by surgery, radiosurgery or embolisation, with the functional aim of reducing the risk of haemorrhage or to alleviate neurological symptoms with an acceptable treatment risk. Few neurocentres have physicians highly skilled in all treatment modalities. Therefore, the prescribed treatment may not be defined from an objective assessment of what is optimal for each individual patient, but rather from local expertise. In this context, more and better data about the natural history and the outcome of different treatments, as well as predictive models, would be valuable to help to optimise the management. Management strategies obviously differ according to local preferences, but results presented in the literature suggest the following strategy: (I) cortically located AVMs with a nidus volume <10 ml could be operated, with or without presurgical embolisation, unless there is a single feeder that can easily be catheterised and embolised for obliteration or other obvious target for embolisation, such as pseudoaneurysms or large fistulae; (II) centrally located AVMs with a nidus volume <10 ml should be treated by radiosurgery, unless suitable for embolisation as indicated above; (III) patients harbouring AVMs with a nidus volume >10 ml could benefit from targeted partial embolisation followed by radiosurgery or surgery, depending on the angioarchitecture; and (IV) AVMs >20 ml nidus volume usually have a high treatment risk with any treatment modality and are not obvious targets for treatment at all.

Adult↗

PubMed2003

Deep and brainstem cavernomas: a consecutive 8-year series.

OBJECT: The goal of this study was to provide epidemiological and clinical data on the management of cavernomas of the basal ganglia and brainstem from a long-term series at one institution. METHODS: All 68 patients who were referred to the authors' department between 1992 and 2000 for deep cavernomas were evaluated by clinic examinations, review of neuroimaging examinations, and review of charts and operative notes. Twenty-nine patients underwent microsurgical procedures, which carried a 69% risk of transitory neurological deterioration. Radical excision was achieved in 25 of these patients, as determined by a review of neuroimages; the remaining four patients all experienced new hemorrhages that led to increased morbidity or even to mortality. Surgical results were better if surgery was performed early, within 1 month posthemorrhage, than if operations were postponed. In selected patients, deep lesions not reaching a pial surface could be safely removed from the thalamus, basal ganglia, or medulla oblongata. Of five patients who underwent gamma knife surgery, two experienced hemorrhages, one at 2 and the other at 5 years following treatment. Patients who did not undergo surgery had a yearly incidence of hemorrhage that was 2% in cases of incidental cavernomas and 7% in symptomatic ones. CONCLUSIONS: Over the long term, outcomes were worse following conservative treatment or shunt insertion surgery than after microsurgery of symptomatic cavernomas. Incidental cavernomas carried a low risk of neurological deterioration. Surgery should follow generally accepted indications, but only with the confidence that total removal can be safely achieved. Surgery that is performed within 10 to 30 days following ictus may be preferable to delayed surgery.

Adult↗

PubMed2002

Intraoperative complications in aneurysm surgery: a prospective national study.

OBJECT: With increasing use of endovascular procedures, the number of aneurysms treated surgically will decline. In this study the authors review complications related to the surgical treatment of aneurysms and address the issue of maintaining quality standards on a national level. METHODS: A prospective, nonselected amalgamation of every aneurysm case treated in five of six neurosurgical centers in Sweden during 1 calendar year was undertaken (422 patients; 7.4 persons/100,000 population/year). The treatment protocols at these institutions were very similar. Outcome was assessed using clinical end points. In this series, 84.1% of the patients underwent surgery, and intraoperative complications occurred in 30% of these procedures. Poor outcome from technical complications was seen in 7.9% of the surgically treated patients. Intraoperative aneurysm rupture accounted for 60% and branch sacrifice for 12% of all technical difficulties. Although these complications were significantly related to aneurysm base geometry and the competence of the surgeon, problems still occurred apparently at random and also in the best of hands (17%). The temporary mean occlusion time in the patients who suffered intraoperative aneurysm rupture was twice as long as the temporary arrest of blood flow performed to aid dissection. CONCLUSIONS: The results obtained in this series closely reflect the overall management results of this disease and support the conclusion that surgical complications causing a poor outcome can be estimated on a large population-based scale. Intraoperative aneurysm rupture was the most common and most devastating technical complication that occurred. Support was found for a more liberal use of temporary clips early during dissection, regardless of the experience of the surgeon. Temporary regional interruption of arterial blood flow should be a routine method for aneurysm surgery on an everyday basis. A random occurrence of difficult intraoperative problems was clearly shown, and this factor of unpredictability, which is present in any preoperative assessment of risk, strengthens the case for recommending neuroprotection as a routine adjunct to virtually every aneurysm operation, regardless of the surgeon's experience.

Adolescent↗