Three cases of AVM at eloquent areas finally treated with conventional microsurgical method

Surgical Outcomes of Awake Craniotomy for Treatment of Arteriovenous Malformations in Eloquent Cortex: A Systematic Review

OBJECTIVE

Arteriovenous malformations (AVMs) located in eloquent brain regions are historically associated with a poor prognosis. Awake craniotomy (AC) with the adjunct of brain mapping has the potential of identifying non-eloquent gyri to maximize resection, thereby theoretically decreasing the risk of neurologic deficits. With limited evidence regarding the efficacy of AC in treatment of eloquent AVMs, this review aims to investigate its surgical outcomes.

METHODS

A systematic search in the PubMed database was performed to identify all relevant studies up to February 2022.

RESULTS

A total of 13 studies were extracted for quantitative analysis, yielding a total of 46 patients. The mean age was 34.1 years, and most patients were female (54.8%). Seizures were the most frequently reported presenting symptom (41%, 19 of 46 cases). Spetzler-Martin Grade III was the most prevalent (45.9%, 17 cases) with a mean nidus size of 32.6 mm. Seventy-four percent of AVMs were located on the left side, with the frontal lobe being the most common location (30%, 14 of 46 cases). The most common eloquent regions were language (47.8%, 22 of 46 cases), motor (17.4%, 8 of 46 cases), and language + motor cortices (13.1%, 6 of 46 cases). Complete resection of AVM was achieved in 41 patients (89%). Intraoperative complications occurred in 14 of 46 cases (30.4%) with transient postoperative neurologic deficits in 14 patients (30.4%).

CONCLUSIONS

AC may enable precise microsurgical excision of eloquent AVMs with preservation of critical brain functions. Risk factors for poor outcomes include eloquent AVMs located in the language + motor regions and the occurrence of intraoperative complications such as seizures/hemorrhage.

Chinese Cerebrovascular Neurosurgery Society and Chinese Interventional & Hybrid Operation Society, of Chinese Stroke Association Clinical Practice Guidelines for Management of Brain Arteriovenous Malformations in Eloquent Areas

Aim: The aim of this guideline is to present current and comprehensive recommendations for the management of brain arteriovenous malformations (bAVMs) located in eloquent areas. Methods: An extended literature search on MEDLINE was performed between Jan 1970 and May 2020. Eloquence-related literature was further screened and interpreted in different subcategories of this guideline. The writing group discussed narrative text and recommendations through group meetings and online video conferences. Recommendations followed the Applying Classification of Recommendations and Level of Evidence proposed by the American Heart Association/American Stroke Association. Prerelease review of the draft guideline was performed by four expert peer reviewers and by the members of Chinese Stroke Association. Results: In total, 809 out of 2,493 publications were identified to be related to eloquent structure or neurological functions of bAVMs. Three-hundred and forty-one publications were comprehensively interpreted and cited by this guideline. Evidence-based guidelines were presented for the clinical evaluation and treatment of bAVMs with eloquence involved. Topics focused on neuroanatomy of activated eloquent structure, functional neuroimaging, neurological assessment, indication, and recommendations of different therapeutic managements. Fifty-nine recommendations were summarized, including 20 in Class I, 30 in Class IIa, 9 in Class IIb, and 2 in Class III. Conclusions: The management of eloquent bAVMs remains challenging. With the evolutionary understanding of eloquent areas, the guideline highlights the assessment of eloquent bAVMs, and a strategy for decision-making in the management of eloquent bAVMs.

One-staged in situ embolization combined with surgical resection for eloquence protection of AVM: technical note

Brain arteriovenous malformations (AVMs) near/within eloquent areas are challenging to treat surgically. The insufficient lesion-to-eloquence distance (LED) is related to poor neurological outcomes. This paper reports the use of in situ embolization combined with surgical resection in a one-staged hybrid operation for eloquent area protection. Nine patients who underwent one-staged in situ embolization combined with surgical resection were selected from the database of a prospective clinical trial (NCT03774017). Nidus got partial in situ embolization in the parts located near/within the eloquence. The rest of nidus was removed via a microsurgical procedure in the same operation. The in situ embolization ensured a sufficient LED to prevent eloquent areas and tracts from being damaged in the subsequent resection. All of the patients achieved complete obliteration with no neurological deficits or complications. One-staged hybrid operation initiates closer cooperation between surgical and endovascular treatments and proposes an integrative therapeutic mode for AVMs. The in situ embolization combined with surgical resection is safe and effective for improving the functional outcome of AVMs with eloquence and tracts involved. The clinical trial is registered at ClinicalTrials.gov (NCT03774017, https://clinicaltrials.gov/ct2/show/NCT03774017 ).

Safe resection of arteriovenous malformations in eloquent motor areas aided by functional imaging and intraoperative monitoring

BACKGROUND

Arteriovenous malformations (AVMs) proximal to motor cortical areas or motor projection systems are challenging to manage because of the risk of severe sensory and motor impairment. Surgical indication in these cases therefore remains controversial.

OBJECTIVE

To propose a standardized approach for centrally situated AVMs based on functional imaging and intraoperative electrophysiological evaluation.

METHODS

We conducted a retrospective analysis of 15 patients who underwent surgical treatment for AVMs in motor cortical areas or proximal to motor projections. Preoperative assessment included functional magnetic resonance and 3-dimensional tractography. Operations were performed under continuous electrophysiological monitoring aided by direct brain stimulation. We identified critical bloody supply to the motor areas by temporary occluding the feeding vessels under electrophysiological monitoring. Clinical outcome was evaluated with the modified Rankin Scale.

RESULTS

Total resection was achieved in 12 cases, whereas electrophysiology limited total extirpation in 3 cases. A significant reduction of motor evoked potentials by up to 15% of the initial values was associated with good recovery of motor function; in contrast, the disappearance of potentials correlated with long-term impairment. The mean follow-up time was 13 months, and clinical assessments revealed overall functional improvement (P < .05). After surgery, 11 patients were asymptomatic or presented with only minor neurological deficits.

CONCLUSION

Surgical resection of AVMs in eloquent motor areas can be considered a safe option for selected cases when performed in conjunction with a detailed functional assessment. Possible selection criteria for surgical treatment are discussed in light of the presented clinical data.

Management and prognosis of cysts developed on long-term follow-up after Gamma Knife radiosurgery for intracranial arteriovenous malformations

BACKGROUND

Delayed cyst formation is a well-recognized complication after radiosurgery for intracranial AVM. The objective of the present study was the evaluation of the different management options for these lesions and the corresponding prognosis of patients.

METHODS

Between 2000 and 2005, 12 patients with intracranial AVM initially treated by GKR were reevaluated at Tokyo Women's Medical University because of delayed cyst formation in the vicinity of the target area. There were 7 men and 5 women. The mean age of the patients was 31.8 years at the time of GKR and 41.1 years at the time of complication. The average period between treatment and diagnosis of the complication constituted 6.7 years. All AVMs had lobar location and showed complete angiographic obliteration after GKR.

RESULTS

The most common neurological signs and symptoms at the time of cyst presentation were headache (10 cases) and seizures (4 cases). Two patients were asymptomatic. Three patients underwent surgery soon after the diagnosis of the cyst, whereas initial observation was done in another 9. Among the latter, 5 patients had to be treated surgically thereafter because of persistent or aggravated neurological symptoms associated with radiological cyst expansion. Four other patients, including both asymptomatic ones, are in stable condition without surgery. Follow-up after treatment of the cyst varied from 7 to 60 months (average, 34.3 months). All patients are in good condition.

CONCLUSIONS

Although delayed formation of cysts after GKR for intracranial AVM should be considered as a complication of the radiosurgical treatment, it has a relatively good prognosis. Observation can be recommended as initial option for compensated and asymptomatic patients.

Use of autologous bone marrow mesenchymal stem cells for healing of free full-thickness skin graft in a zone with pronounced hypoperfusion of soft tissues caused by arteriovenous shunting

A combined graft consisting of a free full-thickness skin flap and cultured autologous fibroblast-like bone marrow mesenchymal stem cells was effectively implanted and healed on the facial soft tissue defect after removal of a pathological vascular conglomeration in a female patient with congenital arteriovenous macrofistulous dysplasia. In order to reduce bloodflow intensity and arteriovenous shunting, repeated endovascular occlusion and transcutaneous ligature of regional vessels from the carotid artery basin feeding the pathological zone was carried out followed by resection of this tumor-like vascular formation.