Moussalem, Charbel

BACKGROUND AND OBJECTIVES: Endoscopic transnasal surgery offers a minimally invasive alternative to transcranial approaches for accessing midline skull base lesions involving the petrous apex and petroclival region. However, lateral access, particularly behind the petrous internal carotid artery (ICA), remains limited. The contralateral transmaxillary (CTM) approach provides a more direct surgical trajectory, more parallel to the petrous ICA. Yet, lateral access through this approach can be restricted by anatomic barriers, including the pterygoid process and lateral buttress of the maxillary sinus. We aimed to evaluate the contralateral transmaxillary-transpterygoid (CTMP) approach, with and without the lateral buttress removal (CTMP-LBR), to determine whether these modifications could enhance surgical access to the petroclival region. METHODS: Ten sides from 5 formalin-fixed, latex-injected cadaveric specimens were dissected to compare CTM, CTMP, and CTMP-LBR approaches. Petrous bone drilling was directed posterolaterally behind the petrous ICA toward the region medial to the cochlea. In addition, 30 sides from computed tomography angiography scans were analyzed to obtain radiographic measurements for each approach. RESULTS: Compared with CTM, both CTMP and CTMP-LBR significantly increased access for retrocarotid petrous bone drilling ( P < .001) and yielded a wider surgical angle relative to midline ( P < .001), in both cadaveric and radiographic analyses. In dissections, 20% of sides required CTM only, 50% benefited from CTMP, and 30% required CTMP-LBR to achieve adequate lateral access. Radiographic analysis revealed that CTMP required a median of 4 mm of pterygoid drilling, whereas CTMP-LBR required 9 mm and enabled a trajectory parallel to the petrous ICA with only 11 mm of soft tissue displacement. Patients with smaller angles between the petrous ICA and the horizontal plane were significantly more likely to benefit from CTMP over CTM ( P = .005). CONCLUSION: Modification of the CTM approach with pterygoid drilling and optional LBR improves retrocarotid access. Preoperative evaluation of the petrous ICA angle may help optimize patient-specific planning in endoscopic petroclival surgery.

BACKGROUND AND OBJECTIVES: Brainstem cavernous malformations (BSCM) can result in spontaneous intracerebral hemorrhage (ICH), often resulting in significant morbidity. We aimed to assess the functional outcome and identify predictors of functional neurological outcome after single and multiple symptomatic hemorrhages. METHODS: As part of an international multicenter collaboration, institutional databases from 3 different tertiary referral centers included BSCM patients with complete baseline characteristics, MRI Data set, ≥1 ICH, and ≥1 follow-up examination followed at our institutions between 2003 and 2023. Functional neurological outcome was obtained using the modified Rankin Scale at diagnosis, before and after each ICH, and last follow-up. Patients were excluded after surgical removal of the lesion and/or loss of follow-up. RESULTS: A total of 383 patients (41.47 ± 15.51 age; 220 [57.4%] female) were included and followed for an average of 63.16 ± 85.75 months. Functional neurological outcome deteriorated in 47.2% ( P = .010) after the second ICH and in 46.5% ( P = .007) after the third ICH. Moreover, the functional neurological status was impaired in 22.3% ( P < .001) of patients at last available follow-up compared with the time of BSCM diagnosis. CONCLUSION: In our study, we observed that the chance of full recovery might decrease with each ICH. We observed a significantly associated neurological deterioration after each ICH compared with initial ICH.

OBJECTIVE Chordomas are rare tumors of the skull base and spine believed to arise from the vestiges of the embryonic notochord. These tumors are locally aggressive and frequently recur following resection and adjuvant radiotherapy. Proton therapy has been introduced as a tissue-sparing option because of the higher level of precision that proton-beam techniques offer compared with traditional photon radiotherapy. This study aimed to compare recurrence in patients with chordomas receiving proton versus photon radiotherapy following resection by applying tree-based machine learning models. METHODS The clinical records of all patients treated with resection followed by adjuvant proton or photon radiotherapy for chordoma at Mayo Clinic were reviewed. Patient demographics, type of surgery and radiotherapy, tumor recurrence, and other variables were extracted. Decision tree classifiers were trained and tested to predict long-term recurrence based on unseen data using an 80/20 split. RESULTS Fifty-three patients with a mean ± SD age of 55.2 ± 13.4 years receiving surgery and adjuvant proton or photon therapy to treat chordoma were identified; most patients were male. Gross-total resection was achieved in 54.7% of cases. Proton therapy was the most common adjuvant radiotherapy (84.9%), followed by conventional or external-beam radiation therapy (9.4%) and stereotactic radiosurgery (5.7%). Patients receiving proton therapy exhibited a 40% likelihood of having recurrence, significantly lower than the 88% likelihood observed in those treated with nonproton therapy. This was confirmed on logistic regression analysis adjusted for extent of tumor resection and tumor location, which revealed that proton adjuvant radiotherapy was associated with a decreased risk of recurrence (OR 0.1, 95% CI 0.01–0.71; p = 0.047) compared with photon therapy. The decision tree algorithm predicted recurrence with an accuracy of 90% (95% CI 55.5%–99.8%), with the lowest risk of recurrence observed in patients receiving gross-total resection with adjuvant proton therapy (23%). CONCLUSIONS Following resection, adjuvant proton therapy was associated with a lower risk of chordoma recurrence compared with photon therapy. The described machine learning models were able to predict tumor progression based on the extent of tumor resection and adjuvant radiotherapy modality used.

Background The Woven Endo-Bridge (WEB) device revolutionized the treatment of wide-necked bifurcation aneurysms by intrasaccular flow diversion. The latest advancement is the WEB-17 system, offering greater flexibility with fewer wires, enabling treatment of smaller distal aneurysms using smaller microcatheters than the WEB-21 system. Methods We conducted a systematic review following preferred reporting items for systematic reviews and meta-analyses guidelines, analyzing data from seven retrospective cohort studies involving 483 aneurysms treated with the WEB-17 device. Statistical analysis computed pooled prevalence rates and 95% confidence intervals using appropriate models for each outcome and R software version 4.3.1 (R Foundation for Statistical Computing, Vienna, Austria). Results Technical success was achieved in 475 out of 483 aneurysms treated with the WEB-17 device, with a success rate of 98.34% (95% confidence interval (CI) = 96.72–99.17). Among the successful cases, 4.97% (95% CI = 1.60–14.39) required adjunctive devices. Adequate occlusion, defined as complete occlusion or neck remnants, was observed in 94.41% (95% CI = 88.17–97.46) of cases. Periprocedural complications were infrequent, with thromboembolic complications occurring in 4.93% (95% CI = 3.29–7.30) of cases, hemorrhagic complications in 1.28% (95% CI = 0.58–2.83), and postprocedural neurologic complications in 0.99% (95% CI = 0.31–3.14). Procedure-related morbidity was observed in 1.71% (95% CI = 0.86–3.39) of cases, and there was one procedure-related mortality reported at 0.21% (95% CI = .03–1.50). Mortality unrelated to the procedure occurred in 1% (95% CI = 0.23–4.15). Conclusion Our findings suggest that the WEB-17 device is associated with a high rate of technical success, favorable angiographic outcomes, and a low rate of periprocedural complications. Further research, including prospective trials, is needed to confirm these findings and establish its safety and efficacy definitively.