Assessing Aneurysm Obliteration and Neck Remnants in 225 Clipped Aneurysms Using Indocyanine Green Video Angiography, Micro-Doppler Ultrasonography and Postoperative Digital Subtraction Angiography.

AIM: To present our experience of 225 clipped aneurysms in 196 patients to compare indocyanine green video angiography (ICGVA), micro-Doppler ultrasonography (MDUSG), and postoperative digital subtraction angiography (DSA) in terms of determining aneurysm obliteration, neck remnants, and parent artery patency. MATERIAL AND METHODS: This retrospective study included 196 patients (108 female and 88 male patients) treated between 2013 and 2016. In all cases, aneurysm neck remnants and vessel patency were assessed using ICG-VA and 16-Hz MDUSG. DSA was performed in every case postoperatively within the first 5 days. RESULTS: The mean patient age was 55.8 years (range, 31-80 years), and the mean follow-up duration was 25 months (range, 2-48 months). Of the 225 clipped aneurysms, 86 were located in the anterior cerebral artery and its branches, 103 in the bifurcation of the middle cerebral artery (MCA) and the branches of the MCA, 34 in the internal cerebral artery and its branches, 1 in the posterior inferior cerebellar artery, and 1 at the basilar apex. We observed 2 neck remnants (0.8%), 2 parent/perforating artery occlusions (0.8%), and 2 residual aneurysm fillings (0.8%). There were no striking differences among the assessed methods. CONCLUSION: ICG-VA, MDUSG, and dome puncturing are all useful techniques in aneurysm surgery for assessing complete obliteration of the aneurysm. In our experience, all the 3 tools are complementary to each other, and none of them is superior to the others. We recommend the use of all 3 tools to obtain a favorable outcome.

Dipyrone attenuates cerebral vasospasm after experimental subarachnoid hemorrhage in rabbits.

BACKGROUND: The purpose of this study was to evaluate the effect of the systemic administration of dipyrone in a triple subarachnoid hemorrhage (SAH) model of cerebral vasospasm in rabbits. METHODS: Experimental subarachnoid hemorrhage was induced in rabbits by injecting autologous arterial blood into the cisterna magna. Digital subtraction angiographies (DSA) were performed before and after the first experimental SAH, and at 30, 45, 60 minutes and 72 hours after the first drug administration to measure the diameter of basilar artery. Intracisternal blood injections were repeated 24 and 48 hours after the first injection. Dipyrone (N.=20) or 0.9% NaCl (N.=20) was administered intravenously after initial SAH induction and repeated at 8-hour intervals intramuscularly. After sacrificing by perfusion-fixation, basilar arteries were removed and sectioned for transmission electron microscopic (TEM) examination. RESULTS: The average basilar artery diameter measured by DSA was 724±19 µm in the control, and 686±29 µm in treatment group before SAH. After SAH, mean basilar artery diameters decreased to 71% and 68% of their basal values, respectively. Dipyrone significantly attenuated the basilar artery diameter at one and 72 hours after the first drug administration, in comparison to the control group. TEM studies showed more edema in the endothelial cells of the basilar arteries of the control group when compared to the treatment group. CONCLUSIONS: Dipyrone showed a beneficial effect in autologous blood-induced basilar artery vasospasm in rabbits. These data support the idea that dipyrone can be a potential candidate drug to be tested in patients suffering from cerebral vasospasm secondary to subarachnoid hemorrhage.

Anterior communicating artery aneurysm surgery: which is the most appropriate head position?

Head positioning and the degree of rotation for anterior communicating artery aneurysm surgery is controversial. With this anatomic study, we aimed to give a broad description of head positioning for various aneurysm dome projections. In addition, with the use of a corrosion-cast technique, a three-dimensional arterial tree was demonstrated, an anterior communicating artery region aneurysm model was prepared, and pictures were taken at various angles. According to our observations, 30-degree head rotation was found to be the most suitable position for the anterior and superior projected aneurysms. For posterior projection, aneurysm neck was best viewed with 15-degree head rotation. Aneurysms projecting inferiorly necessitated the greatest rotation at 45 degrees. Each aneurysm dome projection of the anterior communicating artery aneurysm should be individually considered, and the head position should be adjusted accordingly. The use of appropriate head positions during surgery will prevent the development of postoperative ischemic complications and will increase the success of surgery by preventing unnecessary tissue manipulation.

Does the sphenoid angle effect the operation strategy? Anatomical and radiological investigation.

AIM: The aim of our study is to suggest the sphenoid wing-lesser wing angulation (SWA) importance during surgeries directed to this region. MATERIAL AND METHODS: SWA on 40 skulls were measured bilaterally (n=80). The depth of the middle cranial fossa (DMCF) at the level of the SWA was determined. The same measurements were done on 40 randomly selected computerized tomography (CT) scans bilaterally (n=80). RESULTS: The specimens were classified into 3 groups according the degree of SWA; Group-A, SWA was more than 130° (27%), Group-B, SWA was 110-130° (43%) and Group-C, SWA was less than 110° (28%). MCF was measured (mean) as 10.1 mm in Group-A, 6.4 mm in Group-B and 4.6 mm in Group-C. MCF was increasing with the increase in SWA. CT scans were classified into same procedure. Group-A was 26%, Group-B was 42% and Group-C was 31% fitting in the relevant groups. The superior orbital fissure (SOF) was evaluated according to the Sharma's classification. CONCLUSION: We suggest that by the preoperative evaluation of CT scans measurements the SWA, it is possible to estimate the MCF and the type of SOF. This knowledge may be important for all surgeries requiring removal of the sphenoid wing and these region pathologies.

Neuronavigation-assisted transoral-transpharyngeal approach for basilar invagination--two case reports.

Two patients presented with congenital basilar invagination manifesting as progressive myelopathy. Both patients underwent surgery using a neuronavigation-assisted transoral-transpharyngeal approach. The Brain-LAB Vector Vision navigation system was used for image guidance. The registration accuracies were 0.9 and 1.3 mm. After decompression, posterior stabilization was performed. Both patients had an uneventful postoperative course. The transoral-transpharyngeal approach with the neuronavigation system provides safe exposure and decompression for basilar invagination.

Cervical foraminal area and intervertebral height changes after titanium ring cage placement: preliminary results.

OBJECTIVE: To investigate the effect of titanium ring cage implantation on cervical foraminal area and intervertebral height. METHODS: Twenty-two patients with single level cervical disc herniation were enrolled in this study. All patients underwent a standard anterior cervical discectomy followed by titanium ring cage implantation. Radiographs were used for evaluation of the cervical foraminal area and intervertebral height in the pre- and postoperative periods. RESULTS: Mean intervertebral heights were 0.7 +/- 0.1 cm (preoperative), 1.1 +/- 0.2 cm (early postoperative) and 0.9 +/- 0.2 (final measurement). Increase in intervertebral height at final follow-up was 0.2+/-0.1 cm (22.6+/-8.5%). Mean cervical foraminal areas were 0.4+/-0.1 cm2 (preoperative), 0.5 +/- 0.2 cm2 (early postoperative) and 0.5 +/- 0.1 cm2 (final measurement). Increase in cervical foraminal area at the final follow-up was 0.1 +/- 0.1 cm2. CONCLUSION: Our study demonstrates that cervical intervertebral height and cervical foraminal area significantly increased after cervical ring cage placement but subsidence during the follow-up period negatively affects foraminal area. However, overall, there was a relative increase of foraminal area and intervertebral height when compared with preoperative values. Long-term follow-up is required to further assess the subsidence rate.

Primary intradural extramedullary hydatid cyst.

Spinal hydatid cysts account for 1% of all cases of hydatid disease; primary intradural hydatid cysts are uncommon. We present a case of pathologically confirmed intradural spinal cyst hydatid in an otherwise healthy patient who showed no other evidence of systemic hydatid cyst disease. The patient presented with back pain, paraparesis, and weakness. An intradural extramedullary cystic lesion was identified with magnetic resonance imaging and was shown to be a hydatid cyst by histopathologic examination after surgical removal. To our knowledge, this is the 25th case of hydatid cyst at an intradural extramedullary location reported in the literature.

Chlamydia pneumoniae infection related atherosclerotic clinical variables on carotid stenosis.

OBJECTIVE: Research results showed that Chlamydia pneumoniae infection is related to atherosclerosis. C. pneumoniae infection may exacerbate atherogenesis. We investigated the presence of this microorganism for patients who underwent carotid endarterectomy and evaluated clinical values of C. pneumoniae infection on carotid stenosis. METHODS: Twenty patients with carotid stenosis were enrolled in this prospective study between 1997 and 1999. The patients were observed on whether they were positive or negative in four C. pneumoniae measures, namely; IgA titers, IgG titers, presence of electron microscopy, and immunocytochemistry in the endarterectomy specimens. Possible clinical findings for atherosclerosis were also observed of Chlamydial measures such as the percentage of carotid stenosis, cholesterol and triglyceride levels, smoking status, symptomatic or non-transient ischaemic attack or stroke, previous ischaemic event, calcification at surgery, ulceration on angiographies, ulceration at surgery and hypertension were included in this evaluation. RESULTS: Specific C. pneumoniae IgG were detected as positive in 9 (45%) of 20 patient samples. These patients were regarded as having chronic Chlamydia pneumoniae infection. None of the patients were positive for IgA antibody. This result demonstrated no evidence of reinfection. Immunocytochemistry and electron microscopy were positive in 7 (35%) of the 20 patients and correlated with positive serological results. The proportion of previous ischaemic events, calcification at surgery, ulceration on angiography, and ulceration at surgery were found significantly higher ( p < 0.05 ) for patients who are positive for chlamydial measures than those who are negative. CONCLUSION: The results of this study demonstrated an association between C. pneumoniae to atherosclerosis. The proportion of patients who are positive for Chlamydia measures (IgG titers, electron microscopy, and immunocytochemistry) is significantly higher for those who were positive for each of these clinical variables (PIE, CALCI, U1, and U2) than who were negative. We emphasise, the higher incidence in clinical variables of PIE, CALCI, U1, and U2 in Chlamydia measures positive group may support the association of C. pneumoniae with atherosclerotic events.

Branches of the anterior cerebral artery near the anterior communicating artery complex: an anatomic study and surgical perspective.

The anatomy of the branches of the anterior cerebral artery (ACA) near the anterior communicating artery (ACoA) complex were investigated to minimize neurovascular morbidity caused by surgical procedures performed in this region. Thirty-one cadaver brains were perfused with colored silicone, fixed, and studied under the operating microscope. The recurrent artery of Heubner (RAH), orbitofrontal artery (OFA), and frontopolar artery (FPA) were identified as the branches of the ACA arising near the ACoA complex. The OFA and FPA were identified in all hemispheres. Forty-nine (64%) of a total of 77 RAHs arose from the A2 segment. The OFA always arose from the A2 segment, was consistently the smallest branch, and coursed to the gyrus rectus, olfactory tract, and olfactory bulb. The mean distance between the ACoA and the OFA was 5.96 mm. The FPA arose from the A2 segment in 95% of the specimens, and coursed to the medial subfrontal region. The mean distance between the ACoA and the FPA was 14.6 mm. The RAH, OFA, and the FPA are three branches that arise from the ACA near the ACoA complex. These vessels have similar diameters, but can be distinguished by the final destination. Distinguishing these vessels is important since the consequences of injury or occlusion of the FPA and OFA are significantly less than of the RAH.

L-arginine in focal cerebral ischemia.

Nitric oxide and its precursor, L-arginine, have a great importance in cerebrovascular studies. In this study, we elucidate the dose dependent L-arginine effects on cerebral ischemia. The study involved 96 New Zealand albino rabbits, which were randomly allocated into four groups. The middle cerebral artery was occluded after a modified transorbital approach. Before the occlusion of MCA, each group was intravenously administered three doses of L-arginine i.e. 2.5 mg kg-1 for Group 1, 7.5 mg kg-1 for Group 2, and 12.5 mg kg-1 for Group 3. Thus, each group consisting of 24 animals was listed as 2.5 mg kg-1 (Group 1), 7.5 mg kg-1 (Group 2), 12.5 mg kg-1 (Group 3), and control group (receiving no intervention). Cerebral tissue oxygenazation was measured in parietal area by near infrared spectroscopy in all animals prior to and at 5, 30, and 60 min after MCA occlusion. Six hours after MCA occlusion, all the animals were studied for the area of ischemia (n = 40), edema formation (n = 32), and blood nitrite-nitrate levels (n = 24). At the dose of 2.5 mg kg-1 of L-arginine no differences were detected on ischemic tissue volume, brain edema, cerebral tissue oxygenazation, blood nitrite-nitrate levels when compared to the values of control group. However, with the dose of 7.5 mg kg-1, there were significant improvements in the levels of ischemic tissue volume, brain edema, and nitrite-nitrate levels compared to those of the control group and the 2.5 mg kg-1 group. At a dose of 12.5 mg kg-1, there were further improvements in the levels of ischemic tissue volume, brain edema, penumbral zone nitrite-nitrate levels. After 30 min of occlusion, cerebral tissue oxygenazation values increased in a dose dependent fashion. L-arginine's protective effect on cerebrovascular ischemia shows a dose dependent effect on infract size and tissue water content that may prove beneficial in the treatment of ischemia. However, further dose-dependent studies are needed.

Resolution of cerebral vasospasm with trapidil; an animal model.

Cerebral vasospasm and rebleeding are important clinical phenomena associated with a high mortality rate. Therefore, any promising finding in the laboratory deserves assessment in clinical practice. The present study was designed to examine the possible effects of trapidil on the basilar artery of the rabbit through a cerebral vasospasm model. This experimental study was carried out on 26 adult New Zealand albino rabbits of both sexes weighing 2.5-3.0 kg. A transclival exposure was performed. Vasospasm was produced by an intracisternal injection of autologous blood. After observation of the vasospasm, trapidil was locally applied in increasing concentrations (10(-5)-10(-4) M). The effect of each concentration was measured independently after 10 minutes for each application and was extended to three hours. Trapidil was shown to have a clear spasmolytic effect on the rabbit's basilar artery. These data suggest that trapidil can have a potential use in the treatment of patients suffering from cerebral vasospasm.

The effects of topical L-arginine and Ng-nitro-L-arginine methyl ester after experimental acute spinal cord injury. A light and electron microscopic study.

The primary objective of this study was to investigate the effects of topical L-arginine and Ng-nitro-L-arginine methyl ester vs the role of ischemia in contributing to secondary injury after experimental acute spinal cord trauma. Twenty-six rabbits were submitted to spinal cord compression at the T7/8 level. The animals were divided into three groups: no applied drug (n=6), L-arginine (n=10), and Ng-nitro-L-arginine methyl ester (n=10). L-arginine was topically administered at a dose of 10 micromol (1.742 mg) per kg immediately after acute spinal cord injury. Ng-nitro-L-arginine methyl ester was applied topically at a dose of 10 pmol (10 mg/kg) immediately after acute spinal cord injury. Cortical somatosensory evoked potentials were recorded before injury and 1 min, 15 min, 30 min, and 60 min after injury. Physiological parameters were followed before, during, and I h post injury. Light and electron microscopic analysis was performed in all of the groups. In contrast to group 1, the edema of perineural, axoplasm, or surrounding tissue, the thickening of walls of the arterioles and venules, and the degeneration in myelinated axons in groups 2 and 3 were well observed. However, no differences between group 2 and group 3 occurred.