J Cerebrovasc Endovasc Neurosurg.  2024 Jun;26(2):216-222. 10.7461/jcen.2023.E2023.05.006.

Management of a ruptured posterior inferior cerebellar artery (PICA) aneurysm with end-to-end in situ bypass: Case report

• de Macêdo LP
• Baptista-André DC
• Ugulino-Netto A
• Franke K
• Oliveira Eugênio PV
• Cezar-Junior AB
• Faquini IV
• de Carvalho-Júnior EV
• Almeida NS
• Azevedo-Filho HRC

• KMID: 2556985
• DOI: http://doi.org/10.7461/jcen.2023.E2023.05.006

Abstract

Dissecting posterior inferior cerebellar artery (PICA) aneurysms are uncommon lesions. Their anatomy and the location of the dissection are variable, however, they usually occurs at the origin of the PICA. Dissecting PICA aneurysms generally have non-vascular morphology involving an entire segment of the artery and cannot be cut. Nevertheless, the detection of these vascular lesions has increased latterly, so it is necessary to recognize it and take the appropriate management modalities for these injuries. In this report, we describe a case of a 73-year-old male patient, who presented a history of severe headache, associated with neck stiffness, nausea, vomiting, dizziness, hypoactivity, mental confusion, and walking difficulty. Radiographic investigation with brain computed tomography (CT) showed mild bleeding in a pre-medullary and pre-pontine cistern, and cerebral angiogram showed a dissecting PICA aneurysm. Despite being a challenging treatment, microsurgery management was the chosen modality. It was performed an end-to-end anastomosis between the p2/p3 segments, showing to be effective with good clinical and radiographic outcomes. We discussed an unusual case, reviewing the current literature on clinical presentations, the angiographic characteristics of the dissecting aneurysms of PICA, and evaluating the clinical and angiographic results of patients undergoing microsurgical treatment.

Keyword

Cerebral revascularization; Subarachnoid hemorrhage; Cerebral aneurysm; Fusiform aneurysm

Figure

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  Fig. 1. Brain computed tomography scan without contrast, showing a subarachnoid hemorrhage in prepontine and premedullary cistern.

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  Fig. 2. Cerebral angiogram, showing a dissecting aneurysmal lesion in the anterolateral segment of the right PICA. PICA, posterior inferior cerebellar artery

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  Fig. 3. Far-Lateral approach was performed, under microscopy view, showing a dissecting partially thrombosed aneurysm of PICA (A). It was not amenable to conventional clipping, so the aneurysm was excluded through a direct cut between p2 (lateral bulbar segment) and p3 (tonsilobulbar segment) for an end-to-end reconstruction (B). A end-to-end anastomosis between the lateral bulbar and tonsilobulbar was performed, using nylon10/0 thread with separate single stitches, 2 temporary clips (distal to p2 and proximal to p3), heparin, papaverine, and methylene blue (C). Final aspect at the end of the procedure after the release of the temporary clips (D). PICA, posterior inferior cerebellar artery

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  Fig. 4. Control cerebral angiogram, showing effective treatment of the dissecting PICA aneurysm. PICA, posterior inferior cerebellar artery

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  Fig. 5. The patient remained clinically and neurologically stable, with no new complaints and made an excellent recovery.

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