Louis-Marie Terrier

Background/Objectives: Multilevel lumbar spinal stenosis (MLSS) is frequently encountered in patients undergoing surgery for lumbar spinal stenosis, yet the optimal extent of decompression remains debated. While multilevel decompression (MLD) may address all radiological stenotic levels, it may also increase surgical invasiveness and operative time. Minimally invasive endoscopic techniques such as unilateral biportal endoscopy (UBE) allow for targeted decompression and facilitate staged surgical strategies. The aim of this study was to evaluate the clinical outcomes of selective single-level decompression (SLD) using UBE in patients presenting with MLSS. Methods: This retrospective monocentric observational study included consecutive adult patients with MLSS who underwent decompression using UBE between December 2022 and July 2025. MLSS was defined as the presence of at least two lumbar levels with Schizas grade B or higher stenosis. Patients undergoing prior lumbar surgery or presenting with non-degenerative pathology were excluded. Patients underwent either SLD targeting the symptom-driving level or MLD, depending on the surgical strategy. Patient-reported outcomes included the Oswestry Disability Index (ODI), lumbar visual analog scale (LVAS), and radicular visual analog scale (RVAS). Results: Among 305 patients operated on for lumbar spinal stenosis, 83 (27%) presented with MLSS and were included in the study. Seventy-four patients (89%) underwent initial SLD and nine (11%) underwent MLD. Among patients treated with SLD, 9 (12%) required a second decompression during follow-up, whereas 65 patients (88%) achieved favorable outcomes without further surgery. Across the entire cohort, ODI, LVAS, and RVAS improved significantly after surgery. Operative time was significantly longer in the MLD group (122 ± 28.1 min vs. 58.1 ± 12.0 min; p < 0.001). These findings support the feasibility of a symptom-driven selective decompression strategy for MLSS using UBE. In our cohort, most patients experienced meaningful functional improvement after SLD without requiring additional surgery. Although a staged approach may necessitate secondary intervention in a minority of patients, selective decompression may help limit surgical extent in carefully selected patients while preserving favorable clinical outcomes. Conclusions: Selective SLD using UBE was associated with significant clinical improvement in most patients with MLSS while reducing operative time and surgical extent. A stepwise strategy targeting the dominant symptomatic level may represent a feasible minimally invasive approach for selected patients with MLSS. Prospective studies are needed to confirm these findings.

Purpose: Degenerative lumbar spinal stenosis (DLSS) represents an increasing challenge due to the aging population. The natural course of untreated DLSS is largely unknown. For the acute DLSS decompensations, the main concern remains the opportunity and timing of surgery, i.e. does emergency decompression improve the neurological prognosis? This question continues to be controversial, and we’ve tried to clarify it. Methods: We conducted a retrospective analysis of 85 consecutive patients who underwent surgery for decompensated DLSS between January 2020 and 2024. Results: All patients presented with motor deficit (84.7%) and/or genital-sphincter dysfunction (25.9%). Surgical procedures included decompression alone (77.6%), decompression with discectomy (18.8%), or decompression with arthrodesis (3.5%). Complete neurological recovery was observed in 53 patients (62.4%) by the first follow-up visit (mean 4.6 months), while 32 patients (37.6%) had persistent neurological sequelae at final FU (mean 11.8 months). No significant association was found between neurological recovery and surgical timing, regardless of intervention within 48 h ( p = 0.529), 7 days ( p = 0.391), 15 days ( p = 0.213), or 1 month ( p = 0.435). Additionally, neither the degree of stenosis on MRI ( p = 0.147), initial deficit severity ( p = 0.06), patient age ( p = 0.410), nor number of muscles involved ( p = 0.328) were significantly associated with recovery. Conclusion: Our findings suggest that urgent surgical intervention for decompensated DLSS does not significantly improve neurological outcomes.

The trigeminal system is considered a prominent actor in brain nociceptive innervation. The trigeminovascular system is mainly composed of pseudounipolar neurons located within the trigeminal ganglion, whose dendrites originate in cerebral blood vessels. Anatomical studies demonstrating anatomical continuity between perivascular fibers and the trigeminal system are lacking. This issue is addressed in this study. Eleven cadaveric heads obtained from a body donation program were fixed in formalin. We performed a microanatomical study of the cavernous carotid‐trigeminal interface and a histological examination of the tissue bridges crossing the virtual space between the medial aspect of the trigeminal ganglion and ophthalmic nerve and the lateral aspect of the cavernous segment of the internal carotid artery. Very strong adhesion was observed between the horizontal segment of the artery and the ophthalmic nerve in all specimens. The virtual space in this interface was crossed by a web of delicate filaments. Histological examination demonstrated the presence of nerve fibers in all samples. In this study, the carotid‐trigeminal interface has been described in greater detail than ever before and could provide insight into disorders related to the trigeminovascular system. As the present results do not allow the exact nature of the axons to be affirmed, further investigation is necessary.

The role of the trigeminal system in facial and dural sensitivity has been recognized for a long time. More recently, the trigeminal system has also been considered a prominent actor in brain nociceptive innervation. It is the anatomical substrate of several frequent conditions, such as primary or secondary headaches, trigeminal neuralgia, and other orofacial pains. Appreciation of the delicate anatomical arrangement of the trigeminal pathway is one of the keys to understanding these conditions’ pathophysiology and to proposing innovative treatments. This review provides a structured presentation of existing knowledge about the trigeminal system, from classical anatomical data to the most recent literature. First, we present the organization of the trigeminal pathway from the trigeminal divisions, nerve, and nuclei to the thalamus and somatosensory cortex. We describe the neurons and fibers’ repartition at each level, depending on the location (somatotopic organization) and the type of receptors (modal organization). Such a dual somatotopic-modal arrangement of the trigeminal fibers is especially clear for the juxtapontine segment of the trigeminal nerve and the trigeminal nuclei of the brainstem. It has significant clinical consequences both for diagnosis and treatment. Second, we explore how the trigeminal system is modulated and involved in reflexes, for instance the trigemino-cardiac and the trigemino-autonomic reflexes, which could play an essential role in the autonomic symptoms observed in cluster headache. Finally, we present how to interact with this complex system to relieve pain mediated by the trigeminal system. This section covers both neuromodulatory and lesional approaches.

Supratentorial sensory perception, including pain, is subserved by the trigeminal nerve, in particular, by the branches of its ophthalmic division, which provide an extensive innervation of the dura mater and of the major brain blood vessels. In addition, contrary to previous assumptions, studies on awake patients during surgery have demonstrated that the mechanical stimulation of the pia mater and small cerebral vessels can also produce pain. The trigeminovascular system, located at the interface between the nervous and vascular systems, is therefore perfectly positioned to detect sensory inputs and influence blood flow regulation. Despite the fact that it remains only partially understood, the trigeminovascular system is most probably involved in several pathologies, including very frequent ones such as migraine, or other severe conditions, such as subarachnoid haemorrhage. The incomplete knowledge about the exact roles of the trigeminal system in headache, blood flow regulation, blood barrier permeability and trigemino‐cardiac reflex warrants for an increased investigation of the anatomy and physiology of the trigeminal system. This translational review aims at presenting comprehensive information about the dural and brain afferents of the trigeminovascular system, in order to improve the understanding of trigeminal cranial sensory perception and to spark a new field of exploration for headache and other brain diseases.

BACKGROUND: Predictors of visual outcomes after optic nerve decompression are controversial. OBJECTIVE: To identify the predictors of poor visual outcomes after surgery of meningiomas responsible of a compressive optic neuropathy. METHODS: We focused on paraoptic meningiomas (POMs), which gathered tuberculum sellae meningiomas (TSMs) and anterior clinoid meningiomas (ACMs) responsible for visual impairment or threatening visual function, that underwent surgery at our institution between January 2009 and December 2015 and analyzed the clinical and radiological findings of our patients. RESULTS: Among 112 patients who underwent surgery for a POM, a preoperative visual deficit was present in 108 patients (96.4%). Six months after surgery, 79 patients (70.5%) had a visual improvement, 15 patients (13.4%) had an unchanged vision, and 18 patients (16.1%) had deteriorated vision. A preoperative visual deficit of 6 mo or more was a strong predictor of poor visual outcome after surgery (P = .034). Poor visual outcome after surgery was not significantly related to the size of the tumor (P = .057), the age of the patient (P = .94), or the tumor extension into the optic canal (P = .47). CONCLUSION: The duration of preoperative visual deficit was found to be a strong predictor of poor visual outcomes after surgery in POMs Other predictors of poor visual outcomes are still needed and are currently under evaluation in a prospective study at our institution.