Postoperative cerebral air embolism with delayed abnormal brain MRI findings.

Cerebral air embolism (CAE) is a rare but well-known complication resulting from invasive medical procedures; however, previous studies have not examined the postoperative longitudinal MRI changes in CAE. In particular, the likelihood that such changes may be observed after an initial delay when using magnetic resonance imaging (MRI) has not been explored. We herein report a case of CAE with no MRI abnormalities 4 h after a pulmonary vein isolation (PVI) procedure and where the first abnormality was found 22 h after the procedure. A 65-year-old man underwent PVI for paroxysmal atrial fibrillation and showed no signs of recovery from anesthesia after the procedure; thus, he was transferred to our emergency department for further examination. Neurological examination revealed conjugate eye deviation to the right and quadriplegia. Although initial computed tomography (CT) and MRI revealed no abnormalities, CAE was suspected, and a high-concentration oxygen treatment was administered. MRI performed 22 h after the procedure revealed restricted diffusion affecting the cortical areas. At the same day, he was transferred for hyperbaric­oxygen chamber treatment. After 7 days of treatment, the patient recovered clinically and neurologically. He regained consciousness and was able to communicate. As suggested by this case, CT and MRI findings may fail to reveal CAE abnormalities initially. In such cases, as urgent treatment is necessary, it is important to consider diagnosing CAE based on the patient's history and administering a high concentration of oxygen. Finally, to reach a correct diagnosis, repeated brain MRI should be considered for patients with suspected CAE.

Paraneoplastic Cerebellar Degeneration and Lambert-Eaton Myasthenic Syndrome with SOX-1 Antibodies.

A 69-year-old man was admitted to our hospital for progressive muscle weakness in both lower limbs and limb ataxia (day 0). Nerve conduction studies showed low compound muscle action potential amplitudes at rest and increased amplitudes after maximum voluntary contraction. Blood testing revealed SOX-1 antibodies. He was diagnosed with paraneoplastic cerebellar degeneration and Lambert-Eaton myasthenic syndrome (PCD-LEMS). He died from aspiration pneumonia on day 9. Small-cell lung carcinoma (SCLC), which had not been obvious on computed tomography, was found during the autopsy. Patients with PCD-LEMS who test positive for SOX-1 antibodies should be carefully evaluated for SCLC.

A Case of Invasive Aspergillus Rhinosinusitis Presenting with Unilateral Visual Loss and Subsequently Associated with Meningitis, Subarachnoid Hemorrhage, and Cerebral Infarction.

Visual impairment can occur because of several mechanisms, including optic nerve disease and occasionally fungal sinusitis. An 87-year-old man presented with the loss of right visual acuity; he was diagnosed with optic neuritis. Steroid pulse therapy was not effective. One month later, he became unconscious because of meningitis, following which treatment with ceftriaxone and acyclovir was initiated. However, his consciousness deteriorated because of a subarachnoid hemorrhage caused by a ruptured aneurysm. Meningitis and vascular invasion caused by fungal rhinosinusitis were suspected, and the sinus mucosa was biopsied. He was pathologically diagnosed with invasive Aspergillus rhinosinusitis. Despite continuous liposomal amphotericin B administration, he died of cerebral infarction, following a right internal carotid artery occlusion. It is important to consider the possibility of Aspergillus as an etiological agent, especially when cerebrovascular events are associated with visual impairment.