The use of an endoscope in exoscopic transcranial neurosurgery for skull-base lesions has not yet been investigated. Thus, this study aimed to investigate the advantages, disadvantages, and safety of “simultaneous temporary use of an endoscope during exoscopic surgery” (exo-endoscopic surgery (EES)). Consecutive exo-endoscopic surgeries performed by experienced neurosurgeons and assistants were analyzed. Surgical complications and time were compared with previous consecutive microsurgeries performed by the same surgeon. A questionnaire survey was conducted on 16 neurosurgeons with experience in both “temporary simultaneous use of endoscope during microscopic surgery” (micro-endoscopic surgery (MES)) and EES. EES was performed in 18 of 76 exoscopic surgeries, including tumor removal (n = 10), aneurysm clipping (n = 5), and others (n = 3). There were no significant differences in operative time, anesthesia time, or complications from microsurgery by the same operator. According to the questionnaire survey results, compared with MES, EES had a wider field of view due to its lack of an eyepiece, was easier when loading and unloading instruments into and out of the surgical field, and was more suitable for the simultaneous observation of two fields of view. Overall, 79.2% of surgeons indicated that EES may be better suited than MES to simultaneously observe two fields of view.

Lipomas of the cerebellopontine angle (CPA) and internal auditory canal (IAC) are relatively rare tumors. Acoustic neurinoma is the most common tumor in this location, which often causes hearing loss, vertigo, and tinnitus. Occasionally, this tumor compresses the brainstem, prompting surgical resection. Lipomas in this area may cause symptoms similar to neurinoma. However, they are not considered for surgical treatment because their removal may result in several additional deficits. Conservative therapy and repeated magnetic resonance imaging examinations for CPA/IAC lipomas are standard measures for preserving cranial nerve function. Herein, we report a case of acoustic neurinoma and CPA lipoma occurring in close proximity to each other ipsilaterally. The main symptom was hearing loss without facial nerve paralysis. Therefore, facial nerve injury had to be avoided. Considering the anatomical relationships among the tumors, cranial nerves, and CPA/IAC lipoma, we performed total surgical removal of the acoustic neurinoma. We intentionally left the lipoma untreated, which enabled facial nerve preservation. This report may be a useful reference for the differential diagnosis of similar cases in the future.

Orbital emphysema after nose-blowing is an uncommon condition and can appear without a trigger. Herein, we reported a case of orbital emphysema after nose-blowing and performed a literature review. A 68-year-old man fell and sustained an injury near his left orbit. No symptoms were noted. He noticed a left periorbital swelling after blowing his nose. Through computed tomography examination, he was diagnosed with subcutaneous emphysema. There are no previous reports that have reviewed the clinical features, need for surgery, and severity of symptoms of subcutaneous emphysema after nasal swallowing due to different factors. We retrospectively analyzed a cohort of 48 cases by searching PubMed to clarify these issues. Regarding the emphysema trigger, 21 cases had an injury or had previously undergone surgery. In 34 cases, conservative treatment was required, while surgery was selected in the acute phase in 6 cases and after the acute phase as a radical cure in 8 cases. Reduced visual acuity, diplopia, exophthalmos, facial hypoesthesia, and color disorders were noted and were more common among surgical cases. The literature review revealed no association between fracture location and the need for surgery; furthermore, surgery was less required in non-trauma cases, excluding osteoma, than in trauma cases (p = 0.0169). Our study reveals that a strict follow-up examination of visual symptoms is necessary for the first 2 days in cases of subcutaneous emphysema caused by nose blowing after facial trauma.