Atlantoaxial rotatory fixation (AARF) occurs commonly in children who have undergone trauma. It is usually corrected with conservative therapy. In this report, however, the patient was an adult with AARF who was treated surgically. A 64-year-old woman presented with a 1-year history of spastic gait and hand clumsiness. Imaging studies revealed the presence of AARF, os odontoideum, and severe spinal cord compression at that spinal level. As the AARF had not been responded to head traction with a halo device, we decided to treat the patient with in situ posterior fixation. Because the rigid dislocation was present between the atlas and the axis, we were forced to make an unusual instrumentation construct. Neurological symptoms other than hand numbness diminished after the surgery, and arthrodesis was obtained between the occiput and the axis. It should be noted that surgical planning for posterior instrumentation construct is required when rigid AARF is treated surgically.

A 68-year-old woman presented with segmental aplasia of bilateral internal carotid arteries accompanied by unruptured intracranial aneurysms. The abnormality was discovered incidentally at the age of 44 years. Cerebral angiography showed occlusion of bilateral internal carotid arteries, and the carotid territory was supplied by each posterior communicating artery with small intracranial aneurysms. Endovascular treatment for the intracranial aneurysms was planned. However, the patient did not want to undergo the endovascular procedure because of the increased risk due to the associated bilateral carotid abnormalities. Cerebral angiography was performed again at the age of 66 years, and the size of the aneurysms had not changed. Based on their segmental identity, aplasia of segment 6 of the internal carotid artery (ICA) including the first portion of the ophthalmic artery was observed bilaterally.

A 74-year-old male presented with an intracranial hemorrhage caused by multiple dural arteriovenous fistulas (DAVFs) in the left transverse sinus and right sigmoid sinus. Four months previously, the patient underwent tongue cancer removal with lymph node dissection and ligation of the right internal jugular vein. Endovascular embolization (transvenous and transarterial embolization) resulted in the complete disappearance of the fistulas. Follow-up angiography revealed new arteriovenous shunts at the superior sagittal sinus and right transverse sinus, and we treated the patient with staged transarterial embolization. Finally, venous congestion almost completely resolved and the DAVFs disappeared without any sign of recurrence. This case speculates the concept of DAVF as an acquired lesion caused by intravenous hypertension and alerts clinicians to take precautions against ligation of the internal jugular vein during a cervical operation.

Nervus intermedius neuralgia is one of the craniofacial neuralgias, which is extremely rare compared with trigeminal or glossopharyngeal neuralgia. Despite its unique symptom, the aetiology remains unclear. We present a case of a surgically treated 36-year-old woman who suffered from paroxysmal stabbing deep-ear pain for over 10 years. Preoperative magnetic resonance imaging demonstrated a vascular loop compressing the root entry zone of the vestibulocochlear nerve between the seventh and eighth cranial nerves, suggesting nervus intermedius neuralgia as a cause of her pain. Surgical exploration revealed that the nervus intermedius was displaced upward by the anterior inferior cerebellar artery. Transposition of the artery from the brainstem relieved the patient’s neurological symptom immediately after the surgery, supporting the hypothesis that nervus intermedius neuralgia could be caused by neurovascular compression.

We report the rare case of a right aortic arch associated with agenesis of the left internal carotid artery. A 75-year-old woman with a medical history of tetralogy of Fallot presented with dizziness. Magnetic resonance angiography revealed agenesis of the left internal carotid artery in addition to a previously diagnosed right aortic arch. The left common carotid artery was present, but it was thin. Computed tomography showed the absence of the left carotid canal. The left anterior cerebral artery was fed via the anterior communicating artery. The left middle cerebral artery was fed via a thickened posterior communicating artery originating from the left posterior cerebral artery. Although a right aortic arch and agenesis of the internal carotid artery are both very rare, association of the two conditions may occur. Both anomalies depend on the abnormal regression of the dorsal aorta during embryonic development. In such a situation, the presence of other anomalies in the cardiac or central nervous system should be taken into consideration.

Schwannoma is a benign peripheral nerve sheath tumor originating from Schwann cells. Most intracranial schwannomas arise from vestibular nerve and schwannoma in the suprasellar region is extremely rare. A 64-year-old man presented with walking disturbance and blurred vision for three months. Lateral hemianopsia in the left eye and brachybasia were observed. Magnetic resonance imaging revealed a suprasellar tumor with strong contrast enhancement associated with communicating hydrocephalus. The cerebrospinal fluid tap test improved gait disturbance. Hypothalamic stimulation test revealed hypo-reaction of GH, FSH and LH. After ventriculo-peritoneal shunting, the tumor was totally removed via a bilateral front-basal approach with a clinical diagnosis of craniopharyngioma. No adhesion was observed between the tumor and surrounding structures such as meninges and brain. The histopathological diagnosis was schwannoma. Here we report a case of suprasellar schwannoma associated with communicating hydrocephalus that has not ever been previously reported, with special reference to its pathogenesis.

We report a 73-year-old woman with de novo arteriovenous malformations (AVMs) that developed in the ipsilateral parietal lobe after craniotomy and aneurysm clipping. While intracerebral AVMs are considered to be congenital lesions, there have been several reported cases of acquired AVM arising after ischemic or traumatic episodes. We summarize previously reported cases of such acquired ‘de novo’ AVMs with a discussion of some pathophysiological responses or factors suggested to promote their development.

A 68-year-old woman presented with generalized seizure due to the left internal carotid artery (ICA) aneurysmal compression of the ipsilateral medial temporal lobe. Computed tomography angiography (CTA) revealed multiple aneurysms of the right persistent primitive hypoglossal artery (PPHA), the right ICA, and the right anterior cerebral artery (ACA). The right PPHA originated from the ICA at the level of the C1 and C2 vertebral bodies and passed through the hypoglossal canal (HC). The PPHA aneurysm was large and thrombosed, which was located at the bifurcation of the right PPHA and the right posterior inferior cerebellar artery (PICA), projecting medially to compress the medulla oblongata. Since this patient had no neurological deficits, sequential imaging studies were performed to follow this lesion, which showed gradual growth of the PPHA aneurysm with further compression of the brain stem. Although the patient remained neurologically intact, considering the growing tendency clipping of the aneurysm was performed. Drilling of the condylar fossa was necessary to expose the proximal portion of the PPHA inside the HC. The key of this surgery was the preoperative imaging studies to fully understand the anatomical structures. The PPHA was fully exposed from the dura to the corner its turning inferiorly without damaging the occipital condylar facet. Utilizing this technique, the neck ligation of the aneurysm was safely achieved without any surgical complications.