|Year : 2021 | Volume
| Issue : 1 | Page : 56-58
Proximal A1 segment aneurysm presenting with visual symptoms: A case report
Shyam Sundar Krishnan1, Pulak Nigam2, Girish R Menon3, Madabushi Chakravarthy Vasudevan4
1 Department of Neurosurgery, Kauvery Hospital; Post Graduate Institute of Neurological Surgery, Dr. A. Lakshmipathi Neurosurgical Centre, Voluntary Health Services Hospital, Chennai, Tamil Nadu, India
2 Department of Neurosurgery, Medanta Multi-Specialty Hospital, Indore, Madhya Pradesh, India
3 Department of Neurosurgery, Kasturba Medical College, Manipal Academy of Higher Education, Karnataka, India
4 Post Graduate Institute of Neurological Surgery, Dr. A. Lakshmipathi Neurosurgical Centre, Voluntary Health Services Hospital, Chennai, Tamil Nadu, India
|Date of Submission||27-Jun-2021|
|Date of Decision||28-Jun-2021|
|Date of Acceptance||18-Jul-2021|
|Date of Web Publication||27-Aug-2021|
Dr. Shyam Sundar Krishnan
Department of Neurosurgery, Kauvery Hospital; Post Graduate Institute of Neurological Surgery, Dr. A. Lakshmipathi Neurosurgical Centre, Voluntary Health Services Hospital, Chennai, Tamil Nadu
Source of Support: None, Conflict of Interest: None
Proximal A1 segment aneurysms are technically challenging aneurysms that require careful and meticulous adherence to surgical principles for optimising the outcomes. They usually present with rupture and headache and visual symptoms are uncommon due to the optic nerve not being in proximity to the aneurysm. Important, delicate perforators arise from the segment and their preservation is the key to a good surgical outcome.
Keywords: A1 segment, aneurysms, perforators, visual symptoms
|How to cite this article:|
Krishnan SS, Nigam P, Menon GR, Vasudevan MC. Proximal A1 segment aneurysm presenting with visual symptoms: A case report. J Cerebrovasc Sci 2021;9:56-8
|How to cite this URL:|
Krishnan SS, Nigam P, Menon GR, Vasudevan MC. Proximal A1 segment aneurysm presenting with visual symptoms: A case report. J Cerebrovasc Sci [serial online] 2021 [cited 2021 Dec 1];9:56-8. Available from: http://www.jcvs.com/text.asp?2021/9/1/56/324811
| Introduction|| |
Aneurysms of the proximal segment of the anterior cerebral artery (A1 artery) are uncommon, accounting for 0.8%–3.4% of intracranial aneurysms.,,, The largest collection of A1 aneurysms published to date has been by Suzuki et al., in 1992 with 38 patients. They are challenging to treat because of their close relationship with perforators. We present report of a case of large A1 aneurysms with relatively uncommon presentation of visual symptoms along with a review of the literature on the subject.
| Case Report|| |
A 63-year-old lady presented with complaints of progressive painless diminution of vision in the left eye for the past 3 months along with occasional headache. At presentation, the patient had no perception of light (PL) in the left eye (WHO grade-5 vision loss). On examination, Glasgow Coma Score was 15. There was no anisocoria, but left pupils had a sluggish reaction to light, visual acuity was normal on right and there was no PL on left. On ophthalmoscopy, fundus on the right was normal while that on the left showed a pale disc. There were no extra-ocular movement deficits. The rest of the neurological examination was normal.
Imaging including computed tomography angiogram showed narrow-necked saccular aneurysm arising from the left A1 segment of the anterior cerebral artery (ACA), pointing anteriorly and inferiorly, measuring 12.1 mm × 10 mm with neck measuring 3.3 mm [Figure 1].
She underwent left frontotemporal craniotomy, trans-sylvian approach and clipping of aneurysm with a reconstruction of ACA. She had an uneventful post-operative course and was discharged with no change in visual status in the left eye.
| Discussion|| |
Aneurysms situated on the A1 segment of the ACA are known for their rarity.,,, They have a low incidence and are rarely described in literature, with very few case series (largest being that of 38 cases by Suzuki et al.) and the rest being anecdotal case reports.,, They have a female preponderance and are more common on right but Suzuki et al., Handa et al. and Locksley have reported a conflicting higher incidence in males.,,,, A high incidence of multiplicity (25%–70%) is also an important feature of A1 segment aneurysms.
The most common presenting feature of A1 segment aneurysms is headache, though other features are not uncommon. Visual symptoms, per se, are uncommon in A1 segment aneurysms due to the segment not being proximate enough to the optic nerve. However, A1 segment aneurysms are very commonly associated with vascular anomalies. In fact, of the 38 cases in series by Suzuki et al., 24 had vascular anomalies. Other authors have similarly reported a large concurrence of vascular anomalies with these lesions, including A1 fenestration, accessory middle cerebral artery (MCA), azygous ACA, fenestration of anterior communicating artery (ACom), A1 elongation, MCA aplasia and interoptic course of ACA., Compressive optic neuropathy has been previously reported by Arcan et al. and Fukiyama et al. among others.,
A number of authors have provided detailed nuances of surgical management of these aneurysms.,,, Still, others have detailed the role and nuances of endovascular treatment in the treatment of this entity.,
The important nuances of surgery for proximal A1 ACA aneurysms are injuries to and/or occlusion of perforating arteries, which make the surgery a technical challenge. These arteries are delicate, arise from the superior and/or posterior aspect of the A1 segment, run backwards and upwards, are commonly involved with the dome and frequently poorly visualised on pre-operative angiography and brain CT angiography., Sparing the perforating arteries around the aneurysms is crucial for a satisfying neurological outcome after A1 segment aneurysm surgery. Lehecka et al. advocate operating under high magnification, adequate mobilisation of the frontal lobe, use of indocyanine green and ensuring that clip does not kink the vessels to ensure that these perforators remain uninjured.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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