Solitaire AB Stent Deployment for Treatment of Basilar Apex Aneurysm via the Posterior Communicating Artery.

AIM: To report the retrograde technique of horizontal stenting through the PCoA using a Solitaire AB stent. MATERIAL AND METHODS: A self-expandable stent was deployed from one posterior cerebral artery to the opposite, across the neck of a ruptured wide-neck basilar apex aneurysm. RESULTS: The technique allowed successful aneurysm embolization with coils in a 53-year-old woman. CONCLUSION: Differently from clipping, where the fetal posterior communicating arteries may represent an obstacle, in endovascular treatment it provides an alternative way to the aneurysm. The Solitaire AB stent is easy to navigate, fully retrievable and repositionable, which enables accurate deployment.

Evaluation of Cerebral Hemodynamics with Color-Coded Duplex Sonography: Normative Values with Correction of Insonation Angles.

BACKGROUND: Transcranial color-coded sonography (TCCS) allows direct observation of arteries and the possibility of correcting the insonation angle for reliable evaluation of hemodynamics. We obtained TCCS reference values of the cerebral hemodynamics after correction of insonation angles. METHODS: We studied 195 healthy adults equally allocated into 3 age groups: 18-40, 41-60, and greater than or equal to 61 years. The middle (MCA), anterior (ACA), and posterior cerebral arteries (PCA) were evaluated through the temporal acoustic window using conventional pulsed transcranial Doppler and TCCS. Peak systolic, end diastolic, and mean blood flow velocities were registered, as well as pulsatility and resistance indices at 0° and with correction by alignment of insonation angle parallel to the blood flow vector. We derived normative values assuming both the parametric and nonparametric distributions. RESULTS: We excluded 33 participants due to inadequate acoustic window (10.3%), carotid disease (2.1%), and embryonic variants (4.6%), leaving out 162 for final analysis (50% female, median age 48 years). The 2.5th-97.5th percentiles of the corrected angle for MCA was 0°-60°, ACA 0°-44°, and PCA 30°-60°. After angle correction, 2.5th-97.5th percentiles for flow velocity of MCA, ACA, and PCA were 37.7-112.5 cm/s, 25.6-71.2 cm/s, and 29.2-80.8 cm/s, respectively. There were wide discrepancies between hemodynamics values obtained with insonation angles at 0° and after angle correction. No differences were found between ultrasound methods at exactly 0° or between hemispheres, however, there were differences according to age and sex. CONCLUSIONS: Specific normative tables should be used in TCCS when the corrected angle is greater than 0° since the hemodynamics values greatly differ after correction of the insonation angle. Further studies are necessary to determine critical cutoffs indicating disease.

[Lateral medullary stroke with extracranial course of the postero- inferior cerebellar artery]. / Accidente cerebrovascular bulbar lateral con trayecto extracraneal de la arteria cerebelosa póstero-inferior.

We present two cases of lateral medullary stroke in subjects with extracranial trajectory of the postero-inferior cerebellar artery. Case 1: a 21-year-old male who presented ataxia and right dysmetria after cervical trauma in a rugby match. Case 2: 56-year-old woman, who started with vertigo and left hemiparesis after intense physical effort. In both cases, the angiographic studies showed an extracranial trajectory of the posterior inferior cerebellar artery. This vessel rarely originates below the foramen magnum, in close relationship with the first three cervical vertebrae and the atlanto-axial joint. At this level, it is exposed to mechanical damage causing dissection, such as direct trauma, abrupt cervical manipulation or prolonged cephalic extension. Therefore, this association should be considered in patients with stroke of the lateral region of the bulb and extracranial trajectory of the posterior-inferior cerebellar artery.

Accidente cerebrovascular bulbar lateral con trayecto extracraneal de la arteria cerebelosa póstero-inferior / Lateral medullary stroke with extracranial course of the postero- inferior cerebellar artery

Presentamos dos casos de accidente cerebrovascular en sujetos con trayecto extracraneal de la arteria cerebeloso póstero-inferior. Caso 1: varón de 21 años, quien presentó ataxia y dismetría derecha luego de un traumatismo cervical en un partido de rugby. Caso 2: mujer de 56 años, quien inició con vértigo y hemiparesia izquierda luego de esfuerzo físico intenso. En ambos casos, los estudios angiográficos mostraron un trayecto extracraneal de la arteria cerebelosa póstero-inferior. Este vaso raramente se origina por debajo del foramen magno, en relación cercana con las primeras tres vértebras cervicales y la articulación atlanto-axial. En este nivel, está expuesta a daño mecánico causante de disección, como por ejemplo trauma directo, manipulación cervical abrupta o extensión cefálica prolongada. Por lo tanto, en pacientes con accidente cerebrovascular de región lateral de bulbo y trayecto extracraneal de la arteria cerebelosa póstero-inferior se debería considerar esta asociación.

We present two cases of lateral medullary stroke in subjects with extracranial trajectory of the postero-inferior cerebellar artery. Case 1: a 21-year-old male who presented ataxia and right dysmetria after cervical trauma in a rugby match. Case 2: 56-year-old woman, who started with vertigo and left hemiparesis after intense physical effort. In both cases, the angiographic studies showed an extracranial trajectory of the posterior inferior cerebellar artery. This vessel rarely originates below the foramen magnum, in close relationship with the first three cervical vertebrae and the atlanto-axial joint. At this level, it is exposed to mechanical damage causing dissection, such as direct trauma, abrupt cervical manipulation or prolonged cephalic extension. Therefore, this association should be considered in patients with stroke of the lateral region of the bulb and extracranial trajectory of the posterior-inferior cerebellar artery.

Doppler evaluation of the posterior cerebral artery in normally grown and growth restricted fetuses.

OBJECTIVE: To evaluate Doppler parameters of the two segments of the posterior cerebral artery (PCA) in normally grown and growth restricted (IUGR) fetuses. METHODS: Normal reference values of the pulsatility index (PI), peak systolic velocity, end-diastolic velocity, and time-averaged maximum velocity from the two segments of the PCA (segment one, PCA-S1; segment two, PCA-S2) were constructed in 350 pregnant women from 20 to 40 weeks of gestation. The association of the two PCA segments with the middle cerebral artery (MCA), and with the umbilical artery was evaluated in 50 IUGR fetuses. RESULTS: In normal fetuses, Doppler parameters from PCA-S1 and PCA-S2 showed similar behavior throughout gestation. In IUGR fetuses, the PI of the two PCA segments was significantly reduced with no differences between them. PCA-S2 PI showed a higher correlation with the MCA-PI (r = 0.73) than PCA-S1 PI (r = 0.63; p = 0.001). IUGR fetuses showed vasodilatation in the PCA earlier than in the MCA disregarding the umbilical artery-PI value. CONCLUSION: In IUGR fetuses, the two segments of the PCA show signs of vasodilatation earlier than the MCA. As IUGR fetuses deteriorate, the two segments of the PCA and the MCA behave similarly.

Intracranial aneurysms associated with a double origin of the posterior inferior cerebellar artery.

The posterior inferior cerebellar artery (PICA) frequently has a variable course and target territory. However, double origin PICA is a rare finding. Its significance is uncertain, but it has been associated with intracranial aneurysms localized at the PICA proper or at a distant site. The presence of this variation imposes specific challenges. We describe two cases of double origin PICA, one of them associated with an ipsilateral PICA aneurysm. The role of this finding was critically reviewed. A literature search identified 23 cases of double origin PICA, including both cases reported in this paper. Intracranial aneurysms were strongly associated with double origin PICA (71% in 21 detailed cases of double origin PICA). The current patient harboring a PICA aneurysm was successfully treated by endovascular trapping. In the setting of double origin PICA aneurysms, this variation beneficially affects the treatment choice once the two limbs enable the safe sacrifice of the channel involved, with preservation of blood flow through the other channel.