Distal Anterior Cerebral Artery Kissing Aneurysms in a Child

Sir, Aneurysms with their origin from a single artery or different arteries but walls of both aneurysms shared partially are termed as kissing aneurysms.[1] The incidence of intracranial kissing aneurysms is less than 1%.[2] These aneurysms are most commonly found in the supraclinoid internal carotid artery (ICA) followed by the distal anterior cerebral artery (DACA).[3] Aneurysms of the DACA constitute only 5% of all intracranial aneurysms. They are infrequently observed in the pericallosal and callosomarginal arteries. The kissing aneurysms of the DACA are very rare.[4] Only 19 cases of kissing aneurysms of the DACA have been reported.[5–22] Management of these kinds of aneurysms with either microsurgical or endovascular techniques is quite challenging due to their deep location of small size, wide neck, and high risk of parent artery occlusion.[23] We report a case of kissing distal anterior cerebral artery aneurysms in a 3-year-old male child managed successfully with microsurgical clipping. A 3-year-old male child was referred to us from the pediatric medicine unit following a headache for the last 7–8 days and fever for 4–5 days. The fever was of low grade and intermittent. Headache was persistent and responded partially to analgesics. A clinical diagnosis of meningitis was made, and intravenous (IV) antibiotics were started following evidence of infection into lumbar cerebrospinal fluid (CSF). The child was not responding to IV antibiotics. A computer tomography (CT) scan of the brain was performed that revealed a hyperdense mass lesion in the interhemispheric fissure [Figure 1a]. Thus, the child was referred to the neurosurgical unit. The patient was fully conscious and well oriented to time, place, and person on examination. His pupils were of normal size and briskly reacted to light. His Hunt and Hess score was grade I, and the World Federation of Neurosurgical Societies (WFNS) score was also grade I. Modified fisher grade was IV. He underwent CT angiography of the brain and neck vessels which revealed a kissing aneurysm of the right DACA. CT angiography of cerebral vessels was done which revealed closely placed outpouching of about 4 × 3 mm size arising from the right pericallosal artery and about 4 × 4 mm size arising from the right callosomarginal artery, suggestive of kissing aneurysms [Figure 1b and c]. The child underwent surgical clipping of aneurysms under general anesthesia. Right parasagittal craniotomy was performed, and aneurysms were exposed via an interhemispheric approach. Intraoperatively, two aneurysms were identified arising from different arteries (one from the right pericallosal artery and another from the right callosomarginal artery). Their walls were weakly adhered to each other [Figure 2a]. After ensuring proximal control, both aneurysms were dissected, separated, and successfully clipped [Figure 2b]. Intraoperatively vascular Doppler was used to confirm flow in the distal arteries. The child had mild weakness in the left lower limb postoperatively which completely improved in over two weeks. A postoperative CT scan showed no new hypodensity in the interhemispheric region and the hydrocephalus [Figure 3a–c]. At six months follow-up, the child was asymptomatic and without any neurological deficit.Figure 1: Computer tomography (CT) scan of the brain plain study showing hyperdense interhemispheric mass lesion with perilesional edema (a). CT angiography of the brain showing two closely placed outpouching arising from the right pericallosal artery and the right callosomarginal artery, suggestive of kissing distal anterior cerebral artery (DACA) aneurysms; sagittal view (b), and coronal view (c)Figure 2: Intraoperative photomicrograph showing kissing aneurysms of DACAs before clipping (a) and after clipping (b)Figure 3: Postoperative CT scan (axial view (a) coronal view (b) and sagittal view (c)) showing no new hypodensity in the interhemispheric region or no evidence of hydrocephalusJefferson first defined kissing aneurysms as two or more aneurysms arising from the same or different arteries sharing adjacent walls.[1] Harada et al.[24] classified kissing aneurysms into two types, depending on the origin from the artery: type 1 necks originating from the same artery and type 2 necks originating from two different arteries. Kissing aneurysms are quite rare in incidence. Literature review revealed only 20 such cases [Table 1] and not a single case in a pediatric population. There is a slight female predominance, and it commonly occurs in middle-aged people.[25] The pathogenesis of kissing aneurysms is quite different from other aneurysms. According to Jagetia et al.,[26] the fenestrated artery has a thin-walled endothelium, and the elastic layer of the artery is discontinuous. So the incidence of kissing aneurysms is high. Jefferson also reported that there might be hereditary predominance for these types of kissing aneurysms.[1] Laitinen et al.[27] described that the embryological remnants like azygos anterior cerebral artery (ACA) and triple ACAs might lead to flow disturbance in the bifurcation of an anterior cerebral artery, leading to bilateral and symmetrical aneurysms.Table 1: Reported cases of kissing distal anterior cerebral artery aneurysms in the literatureKissing aneurysms of DACA are, most of the time, symptomatic. Symptoms range from mild to moderate headaches, speech disturbances, paraparesis, or altered sensorium due to subarachnoid hemorrhage (SAH) or interhemispheric hematoma. Very rarely, they are asymptomatic. If the patient presents with vasospasm, distal arteries may be occluded leading to contralateral lower extremity paralysis.[28] Some people have reported losing control over defecation and micturition, and some have reported having hemiplegia.[27,29] Occlusion of the left DACA can sometimes lead to aphasia. Even aggressive retraction during surgery can also lead to a condition similar to temporary akinetic mutism.[30] Diagnosis for these aneurysms can be made by CT angiography, magnetic resonance (MR) angiography, and digital subtraction angiography (DSA). CT and 3D CT angiography are non-invasive and good diagnostic tests for this kind of aneurysm. It helps in planning a surgical approach to the aneurysms; considering the size, neck, and comparison with bone window helps in planning the surgical procedure. Whether to plan microsurgery or endovascular management depends on the size and neck of the aneurysms.[31] MR angiography is very sensitive for kissing aneurysms and gives 3D-reconstructed images of the kissing aneurysms, but rarely are decisions made on MR angiography alone. Secondly, there is minimal radiation in MR angiography.[32] DSA is the gold standard and provides a complete study of intracranial vessels in real-time. However, this procedure is invasive and requires a high dosage of contrast. It can be used if CT angiography is inconclusive and in non-emergent settings.[33] In our case, we did a CT angiography preoperatively, which was quite enough to detect kissing aneurysms. The definitive management of kissing DACA aneurysm is surgical clipping. Chances of rupture of these kinds of aneurysms are very high as the dome of these aneurysms may come in the way while exposing the neck and achieving proximal control. Surgical approaches to these aneurysms are through the interhemispheric fissure. It gives the advantages of access to both aneurysms and access to proximal control in case of rupture. The aneurysm occlusion rate is very high with clipping, and the rebleeding rate is significantly less. It also allows evacuation of hematoma and prevents vasospasm.[34] While clipping, the only problem is a narrow and deep working corridor with an edematous brain.[35] Endovascular management is far more complex in kissing distal anterior cerebral artery aneurysms. Due to the minimal caliber of distal arteries advancing microcatheter is very difficult and may cause endothelial injury resulting in occlusion of the parent artery. The patient usually presents with vasospasm in ruptured aneurysms, so it is difficult to coil.[36] To date, only one case report of coiling of kissing DACA aneurysm has been reported. In our case, we performed surgical clipping of the aneurysm via parasagittal craniotomy and interhemispheric approach. Postoperatively, the patient was fine and recovered without neuro deficit. Kissing aneurysms of the distal cerebral artery are pretty rare. CT angiography and DSA are required to diagnose and manage such aneurysms. Management this kind of aneurysm is usually surgical. It requires adequate exposure of the proximal artery to gain control as chances of rupture are relatively high in this kind of aneurysms. Endovascular coiling should be ideally avoided as there are chances of occlusion of the distal anterior cerebral artery due to the small caliber and frequent intraprocedural manipulation. 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 Nil. Conflicts of interest There are no conflicts of interest.