Faculty Bibliography

[This corrects the article DOI: 10.3389/fonc.2023.1132777.].

INTRODUCTION/UNASSIGNED:Brain metastases are the most common intracranial tumor diagnosed in adults. In patients treated with stereotactic radiosurgery, the incidence of post-treatment radionecrosis appears to be rising, which has been attributed to improved patient survival as well as novel systemic treatments. The impacts of concomitant immunotherapy and the interval between diagnosis and treatment on patient outcomes are unclear. METHODS/UNASSIGNED:This single institution, retrospective study consisted of patients who received single or multi-fraction stereotactic radiosurgery for intact brain metastases. Exclusion criteria included neurosurgical resection prior to treatment and treatment of non-malignant histologies or primary central nervous system malignancies. A univariate screen was implemented to determine which factors were associated with radionecrosis. The chi-square test or Fisher's exact test was used to compare the two groups for categorical variables, and the two-sample t-test or Mann-Whitney test was used for continuous data. Those factors that appeared to be associated with radionecrosis on univariate analyses were included in a multivariable model. Univariable and multivariable Cox proportional hazards models were used to assess potential predictors of time to local failure and time to regional failure. RESULTS/UNASSIGNED:A total of 107 evaluable patients with a total of 256 individual brain metastases were identified. The majority of metastases were non-small cell lung cancer (58.98%), followed by breast cancer (16.02%). Multivariable analyses demonstrated increased risk of radionecrosis with increasing MRI maximum axial dimension (OR 1.10, p=0.0123) and a history of previous whole brain radiation therapy (OR 3.48, p=0.0243). Receipt of stereotactic radiosurgery with concurrent immunotherapy was associated with a decreased risk of local failure (HR 0.31, p=0.0159). Time interval between diagnostic MRI and first treatment, time interval between CT simulation and first treatment, and concurrent immunotherapy had no impact on incidence of radionecrosis or regional failure. DISCUSSION/UNASSIGNED:An optimal time interval between diagnosis and treatment for intact brain metastases that minimizes radionecrosis and maximizes local and regional control could not be identified. Concurrent immunotherapy does not appear to increase the risk of radionecrosis and may improve local control. These data further support the safety and synergistic efficacy of stereotactic radiosurgery with concurrent immunotherapy.

Sinking skin flap syndrome is a rare syndrome leading to increased intracranial pressure, known to neurosurgeons, yet uncommon and hardly ever reported in trauma patients. In a hospitalized trauma patient with declining neurological status, rarely do we encounter further deterioration by elevating the patients' head, diuresis and hyperventilation. However, after craniectomy for trauma, a partially boneless cranium may be compressed by the higher atmospheric pressure, that intracranial pressure rises to dangerous levels. For such cases, paradoxical supportive management with intravenous fluid infusion, and reverse Trendelenburg positioning, is used to counteract the higher atmospheric pressure, as a bridge to definitive treatment with cranioplasty. These steps constitute an urgent and easily applied intervention to reduce further neurological deterioration, of which every trauma healthcare provider should be aware.

This paper discusses the modern neurosurgeon's use of advanced magnetic resonance imaging in pre-operative and perioperative planning. The effect of advanced imaging on the risk and benefit analysis of surgery is discussed in particular