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  • The impact of CHEK2 status on radiosurgical outcomes in breast cancer brain metastases. Neurosurgical review Harary, P. M., Hori, Y. S., Kattaa, A. H., Tan, S. K., Lam, F. C., Kalra, N., Zagzoog, N., Tayag, A., Ustrzynski, L., Emrich, S. C., Gibbs, I. C., Li, G., Kuno, A., Park, D. J., Chang, S. D. 2026; 49 (1)

    View details for DOI 10.1007/s10143-026-04272-3

    View details for PubMedID 41963546

    View details for PubMedCentralID 3698070

  • Treatment outcomes of stereotactic radiosurgery for sarcoma brain metastases-systematic review. Journal of neuro-oncology Izhar, M., Kattaa, A. H., Hori, Y. S., Lam, F. C., Kalra, N., Zagzoog, N., Tayag, A., Ustrzynski, L., Emrich, S. C., Park, D. J., Chang, S. D. 2026; 177 (2)

    View details for DOI 10.1007/s11060-026-05542-2

    View details for PubMedID 41872576

    View details for PubMedCentralID 10725339

  • Treatment outcomes of cerebral arteriovenous malformations in patients with Hereditary hemorrhagic Telangiectasia: A case series from a Single-Center experience. Journal of clinical neuroscience : official journal of the Neurosurgical Society of Australasia Izhar, M., Al Gharyani, M. F., Hori, Y. S., Kattaa, A. H., Lam, F. C., Kalra, N., Zagzoog, N., Tayag, A., Ustrzynski, L., Emrich, S. C., Park, D. J., Chang, S. D. 2025; 143: 111750

    Abstract

    Hereditary hemorrhagic telangiectasia (HHT) is a rare autosomal dominant vascular disorder characterized by multisystemic arteriovenous malformations (AVMs), including those in the central nervous system. Cerebral AVMs (cAVM), present in up to 23% of patients with HHT, pose a risk of serious neurological complications such as hemorrhage or seizures. Despite their clinical significance, standardized treatment guidelines for cAVM in HHT remain lacking due to limited data. This study evaluates outcomes of stereotactic radiosurgery (SRS) and microsurgical resection for unruptured cAVM in patients with HHT.We retrospectively analyzed 26 patients with clinically or genetically confirmed HHT and radiologically verified unruptured cAVM treated at our institution between 1996 and 2024. Patients were selected based on treatment with either surgery or SRS and a minimum of 1-year follow-up, excluding cases with prior ruptures or previous AVM interventions. Clinical, radiographic, and treatment data were collected and reviewed, including AVM characteristics, intervention parameters, and functional outcomes. The outcomes were changes in functional status measured by the modified Rankin Scale (mRS), complication rates, AVM obliteration, and recurrence. Statistical analysis included the X2 test, Fisher's exact test, and the Mann-Whitney U test, with significance set at p < 0.05. Survival outcomes were assessed using Kaplan-Meier analysis.Among 26 patients, 4 underwent CyberKnife SRS and 22 had microsurgical resection. In the SRS group, all patients were female with a mean age of 39 years at the time of diagnosis; 80 % of lesions achieved complete obliteration at a median follow-up of 5.9 years. Most lesions were superficial, small in volume (mean: 0.16 cm3), and received an average marginal dose of 20.1 Gy. Post-radiosurgical complications occurred in 50 %, primarily headaches and visual disturbances; no hemorrhages or seizures were reported. In the surgery group, 92 % of lesions were obliterated with a median follow-up of 2.75 years. Functional status remained stable or improved in 68 % of patients, with a significant change between pre- and postoperative scores (P = 0.03). Postoperative complications occurred in 23 % of patients, and AVM recurrence was significantly associated with SM grade (P = 0.005). No mortality was observed in either group.In patients with HHT, cAVMs are typically small, multiple, and low-grade with a low risk of hemorrhage. Both surgical resection and SRS are effective treatment options, though further prospective studies are needed to better define and compare their long-term outcomes.

    View details for DOI 10.1016/j.jocn.2025.111750

    View details for PubMedID 41237734

  • Stereotactic radiosurgery for hepatitis C virus-related hepatocellular carcinoma brain metastasis: A retrospective analysis and systematic review WORLD NEUROSURGERY-X Izhar, M., Hori, Y. S., Kattaa, A. H., Lam, F. C., Kalra, N., Zagzoog, N., Tayag, A., Ustrzynski, L., Emrich, S. C., Pollom, E. L., Soltys, S. G., Gephart, M., Park, D. J., Chang, S. D. 2025; 28

    View details for DOI 10.1016/j.wnsx.2025.100541

    View details for Web of Science ID 001602623500001

  • Pilot Study of Optical Topographic Imaging Based Neuronavigation for Mastoidectomy WORLD NEUROSURGERY Zagzoog, N., Rastgarjazi, S., Ramjist, J., Lui, J., Hopfgartner, A., Jivraj, J., Yeretsian, T., Zadeh, G., Lin, V., Yang, V. X. D. 2022; 166: E790-E798

    Abstract

    Mastoidectomy involves drilling the temporal bone while avoiding the facial nerve, semicircular canals, sigmoid sinus, and tegmen. Optical topographic imaging (OTI) is a novel registration technique that allows rapid registration with minimal navigational error. To date, no studies have examined the use of OTI in skull-base procedures.In this cadaveric study, 8 mastoidectomies were performed in 2 groups-4 free-hand (FH) and 4 OTI-assisted mastoidectomies. Registration accuracy for OTI navigation was quantified with root mean square (RMS) and target registration error (TRE). Procedural time, percent of mastoid resected, and the proximity of the mastoidectomy cavity to critical structures were determined.The average RMS and TRE associated with OTI-based registration were 1.44 mm (±0.83 mm) and 2.17 mm (±0.89 mm), respectively. The volume removed, expressed as a percentage of the total mastoid volume, was 37.5% (±10.2%) versus 31.2% (±2.3%), P = 0.31, for FH and OTI-assisted mastoidectomy. There were no statistically significant differences between FH and OTI-assisted mastoidectomies with respect to proximity to critical structures or procedural time.This work is the first examining the application of OTI neuronavigation in lateral skull-base procedures. This pilot study revealed the RMS and TRE for OTI-based navigation in the lateral skull base are 1.44 mm (±0.83 mm) and 2.17 mm (±0.89 mm), respectively. This pilot study demonstrates that an OTI-based system is sufficiently accurate and may address barriers to widespread adoption of navigation for lateral skull-base procedures.

    View details for DOI 10.1016/j.wneu.2022.07.150

    View details for Web of Science ID 000877423400052

    View details for PubMedID 35953033