The use of fluorescent technologies in neurosurgery has a substantial history with applications to vascular and tumor surgery dating back to the 1940s. This review focuses on the applications of fluorescence imaging to intracranial vascular and neoplastic lesions using sodium fluorescein. The authors performed a literature search for articles about the use of sodium fluorescein in neurosurgery. Fifty-five articles were initially retrieved, and 37 of these were appropriate for this review. The subcategorization of these articles revealed 2 describing the properties of fluorescein, 19 articles relating to applications of fluorescein to tumor, 11 relating to vascular applications, and 5 reporting side effects associated with fluorescein use. Articles related to use of this agent in evaluation of CSF leak were excluded. Sodium fluorescein has been reported to be a useful surgical adjunct in resection of neoplastic lesions based on differential fluorescence between normal and neoplastic tissue. There are many reports on the utility of fluorescein in vascular imaging relating to arteriovenous malformations, aneurysms, and vessel anastomosis; however, these reports do not examine primary outcomes. Sodium fluorescein has been judged as generally safe with few reports of severe complications. Sodium fluorescein has demonstrated promise as a useful surgical adjunct in neurosurgery for vascular and neoplastic lesions. It is well tolerated, but further study is required to determine its full utility. Finally, we will introduce a new practical technology that could potentially improve intraoperative application of sodium fluorescein by improving its fluorescence visualization while using substantially lower doses of this dye.

BACKGROUND:

Extradural arteriovenous fistulae (AVFs) are vascular malformations that result from a direct connection between an extradural artery and vein, resulting in a high flow fistula that drains into the epidural venous system. Extradural AVFs may cause myelopathy when distended epidural veins compress the cord or when venous hypertension causes venous stasis within the spinal cord, and are uncommon causes of subarachnoid hemorrhage (SAH), although the presence of intracranial drainage is a risk factor for SAH. There are numerous reports of SAH and AVF with rostral intracranial venous drainage, implying an intradural drainage pathway. To our knowledge, a cervical spinal AVF at the craniovertebral junction (occurring between the occiput and C2) with exclusively extradural drainage and without a significant epidural component has not been described previously.

METHODS:

A retrospective review was performed identifying three patients treated at our hospital with cervical spinal AVF and extradural venous drainage.

RESULTS:

We present three cases of cervical spinal AVF with exclusive extradural venous drainage without accompanying intradural drainage-cranial or spinal. All three patients with exclusively extradural drainage have done well after 24 months of follow-up. The anatomical, clinical, and radiologic features are presented.

CONCLUSIONS:

Patients with cervical AVF and exclusively extradural drainage pathways form a separate entity, representing a subset with a less ominous natural history.

Cerebral arteriovenous malformations (AVMs), though relatively rare, have the propensity to cause potentially fatal conditions, such as intracranial hemorrhage. The presentation of a hemorrhage from an AVM in a pregnant woman warrants the initiation of treatments. An individualized, multimodal therapeutic strategy should be employed for endovascular treatment, such as presurgical embolization. The current treatment options for cerebral AVMs in pregnancy with current recommendations are presented.

From a total of 364 patients who underwent surgery for AVMs, 46 (12.63%) had lesions located interhemispherically. The majority of patients have entered the 4th and 5th age decade. The youngest operated patient was 18 years old and the oldest was 64. The most frequent clinical signs encountered were headaches (13 - 28.2%), epilepsy (21 - 45.65%), motor deficits (12 - 26.08%), sensitivity disorders (8 - 17.39%), speech disabilities (4 - 8.69%), visual field deficits (3 - 6.52%), mental disorders (5 - 10.85%) and alteration of consciousness (4 - 8.69%).The initial imagistic examination consisted of a noncontrast computed tomographic scan, followed by a magnetic resonance angiography (MRA) and a digital subtraction angiography. We included the 46 patients into the Spatzler-Martin scale based on the location, the proximity to the eloquent areas, as well as on the type of the venous drainage. Next we show the number of patients included in every grade of the scale. Grade I - 7 (15.21%) patients, Grade II - 17 (36.95%) patients, Grade III - 19 (41.30%) patients and Grade IV - 3 (6.52%) patients. An interhemispheric surgical approach was used for these AVMs. Excellent and good postoperative results has been obtained in 37 (80.43%) patients, fair results in 5 (10.86%), poor in 2 (4.34%) and 2 (4.34%) patients have died. One of the 2 deaths was caused by a haematoma in the bed of the AVM and the other was caused by a pulmonary embolism.

The best management of patients with unruptured brain arteriovenous malformations (BAVM) is controversial. In this study, we analyzed the stroke rate and functional outcomes of patients having stereotactic radiosurgery (SRS) for unruptured BAVM using the same eligibility criteria and primary end points as the ARUBA trial.Retrospective observational study of 174 ARUBA-eligible patients having SRS from 1990 to 2005.The median follow-up after SRS was 64 months. Fifteen patients (8.7%) had a hemorrhagic stroke at a median of 21 months after SRS. Six patients (3.5%) had a focal neurological deficit and 4 patients died (2.3%). The risk of stroke or death was 10.3% at 5 years and 11.5% at 10 years. Twelve additional patients (6.9%) had a focal neurological deficit from either radiation-related complications (n=7) or subsequent resection (n=5). The risk of patients' having clinical impairment (modified Rankin Score ≥ 2) was 8.4% at 5 years and 12.0% at 10 years. Increasing BAVM volume was associated with both stroke or death (hazard ratio=1.06; 95% confidence interval, 1.0-1.11; P=0.04) and clinical impairment (hazard ratio=1.06; 95% confidence interval, 1.01-1.09; P=0.01). The 10-year risk of stroke or death and clinical impairment for patients with BAVM ≤ 5.6 cm(3) was 5% and 4%, respectively.The observed risk of stroke or death after SRS was approximately 2% per year for the first 5 years after SRS, declining to 0.2% annually for years 6 to 10. Patients with small volume BAVM may benefit from SRS compared with the natural history of unruptured BAVM over the planned follow-up interval of the ARUBA trial (5-10 years).

Vein of galen malformation (VOGM) is a very rare disease which affects blood vessels of the brain. In general population the incidence is estimated at 1%. Treatment of choice is transluminal embolization. We present the case of five-month-old child with low degree heart failure, hydrocephalus and significantly delayed psychomotor development. MR examination reveals a vein of Galen malformations, wall type (type I according to Yasargil) 6 cm in diameter, with venous drainage to the sinus rectus. The enlarged vein filled with thrombus. It causes brain stem compression. Angiography shows one feeder leading to the VOGM, from right posterior brain artery. Lesion was treated with two embolic materials: 5 coils and 2 ml of ONYX. Angiography confirmed total exclusion of the fistula and the circulation in the vein of Galen. One of the most important elements of treatment is to perform a proper diagnosis and evaluation of lesions morphology. With proper technique, high skills and proper equipment, intravascular embolization of vein of Galen malformation is an effective treatment.

Intracranial arteriovenous posterior circulation malformation was planned to embolize by onyx injection after acute coil embolization of ruptured flow-realeted aneurysm of posterior cerebral artery. Control angiography revealed completely embolized malformation with normal vessel patency at the end of procedure. There were no adverse events related to this procedure and no neurologic deficit at the discharge.

BACKGROUND::

Indocianine Green Videoangiography (IGV) raises important limitations when we use it in vascular pathology, especially in cases with arterialization of the venous system like arteriovenous malformations and fistulae.

OBJECTIVE::

Our objective was to provide a simple procedure that overcomes the limitations of conventional IGV. We define IGV in negative (IGV-IN), so-called because in its first phase the vessel to analyze is clipped, and report 3 cases of intracranial dural arteriovenous fistulae treated with this procedure.

METHODS::

In 2011 we applied IGV-IN to 3 patients from our center with Borden type III intracranial arteriovenous fistulae.

RESULTS::

In all three cases IGV-IN enabled both diagnosis and post-DAVF exclusion control in one integrated procedure no longer than 1 minute, requiring only one visualization.

CONCLUSION:

: IGV-IN is an improvement over the conventional IGV method, and is able to provide more information in a shorter period of time. It is an intuitive and highly visual procedure, and more importantly, it is reversible. Studies with larger samples are necessary to determine whether IGV-IN can further reduce the need for post-operative DSA.

Treatment options for dural arteriovenous fistulas (DAVFs) have expanded with the application of stereotactic radiosurgery (SRS). Our objective was to provide guidelines about the use of SRS in symptomatic patients with imaging-identified DAVFs of the brain. The authors reviewed evidence-based medicine and clinical experience with radiosurgery for DAVFs of the brain and developed guidelines and provided a scientific foundation for patients and physicians. Major recommendations include the definition of DAVF patients suitable for various management strategies ranging from observation to surgical excision to endovascular embolization and SRS. Combined SRS and embolization is an effective management strategy for DAVFs, including those that have recurred after initial embolization. The effect of prior embolization has been evaluated. SRS before embolization facilitates the better recognition of the entire target. For selected DAVF patients who are not eligible for embolization or surgery, SRS alone is an effective treatment option. The dose range for DAVFs is similar to that of arteriovenous malformations. A clinical algorithm for the potential role of SRS for a symptomatic brain DAVF was defined. These guidelines provide a framework for professional judgment and treatment selection alternatives for the management of DAVFs.