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Connections between Plio-Pleistocenic tectonic activity and geomorphological evolution were studied in the Pardu Valley and Quirra Valley (Ogliastra, East Sardinia). The intensive Quaternary tectonic activity in Sardinia linked to the opening of the Tyrrhenian Basin is known. In Eastern Sardinia, it manifests with an uplift that is recorded by geomorphological indicators, such as deep-seated gravitational slope deformation, fluvial captures, engraved valleys, waterfalls, and heterogeneous water drainage. The Pardu River flows from the NW toward the SE and then abruptly changes direction toward the NE. At this point, a capture elbow adjacent to the current head of the Quirra River is well developed. The Quirra River, in its upstream part, flows at altitudes approximately 200 m higher than the Pardu River. It also shows an oversized and over-flooded valley with respect to the catchment area upstream. This setting indicates that the Pardu River, which previously flowed south along the Quirra River, was captured by the Pelau River. We analyzed long-term landslides with lateral spreading and sackung characteristics, which involve giant carbonate blocks and underlying foliated metamorphites in both valleys. The use of LiDAR, high-resolution uncrewed aerial vehicle digital photogrammetry (UAV-DP), and geological, structural, and geomorphological surveys enabled a depth morphometric analysis and the creation of interpretative 3D models of DGSDs. Space-borne interferometric synthetic aperture radar (InSAR) data using ERS and Sentinel-1 satellites identified downslope movement of up to 20 mm per year in both Pardu Valley flanks. Multi-source and multi-scale data showed that the state of activity of the DGSDs is closely linked to the geomorphological evolution of the catchment areas of the Rio Pardu and Rio Quirra. The intense post-capture erosion acted in the Rio Pardu Valley, giving it morphometric characteristics that were favorable to the current evolution of the DGSDs, while the Rio Quirra Valley presents paleo-DGSDs that have been fossilized by pre-capture terraced alluvial deposits.

Introduction Cerebrospinal‐venous fistulae (CSF‐VFs) represent a pathologic, low‐flow direct connection between the intrathecal space, usually at the level of a diverticular dilation of a nerve root sleeve, and the thoracolumbar venous system. They can cause CSF hypovolemia resulting in an often‐debilitating intracranial hypotension syndrome. Lateral decubitus CT or DSA myelography (CTM, DSM) are the gold‐standard modalities for diagnosing these entities. Their high spatial and temporal resolution allows visualization of the abnormal connection between the two spaces. Yet, the small size and low flow make CSF‐VFs radiographically subtle, and may not be consistently visualized even after a correctly‐performed CTM/DSM, requiring repeated invasive procedures to definitively establish or exclude their presence. Opacification of the renal excretory system 30‐60 minutes after lateral decubitus myelograms is thought to be a highly sensitive and specific indirect sign of the presence of a CSF‐VF 1,2, as this amount of time is considered insufficient to allow arachnoid reabsorption of contrast. Renal pelvises hyperdensity or its absence after a negative decubitus CTM/DSM can prompt further myelographic investigation or definitively rule out the presence of a CSF‐VF on the side of the examination, respectively. Methods We present three patients with severely symptomatic CSF‐VFs treated at our hospital between 2021 and 2023. All patients were females (range: 50‐60 years old). All three patients underwent bilateral diagnostic lateral decubitus DSM/CTM. Exams were performed at least 72 hours apart in order to allow complete clearance of intrathecal contrast. After each myelographic acquisition, patients remained in the lateral decubitus position until abdominal CT imaging was performed at 30 and 45 minutes to detect the presence of contrast in the renal collecting system. Results Patients 1 and 2, had a CSF‐VF between nerve root dural diverticula and the azygos system that was directly visualized on lateral decubitus CTM (patient 1: right T10‐T11, patient 2: left T8‐T9). Contrast was detectable in the renal pelvises after myelography was performed on the affected side, and not detectable after the contralateral investigation. One fistula was treated via CT‐guided targeted blood patch and fibrin glue injection and the other via endovascular Onyx embolization of the tributary Intercostal veins. Patient 3 had an extremely slow flow CSF‐VF at the right T11‐12 level that was identified only after 5 right‐sided decubitus myelograms with both modalities. The repeated exams were based on the presence of contrast in the renal pelvises after each right‐sided procedure and on the absence of renal opacification after the left‐sided myelograms. Eventually, a CSF‐VF was identified. Successful Onyx embolization of the foraminal veins of the R T11‐12 levels was performed. All three patients had complete resolution of symptoms. Conclusion Contrast presence in the renal excretory system after a lateral decubitus CTM/DSM is a potentially highly sensitive and specific indirect diagnostic sign that can establish or exclude the presence of a CSF‐VF on the examined side. It could be particularly helpful when the fistula is not initially detected, as it can prompt aggressive continuation of the myelographic work‐up. Similarly, it can exclude its presence on one side, sparing the patient invasive and low yield diagnostic procedures.

Introduction Moyamoya is a chronic occlusive cerebrovascular disease characterized by progressive steno‐occlusion of intracranial internal carotid arteries (ICAs) and their proximal branches (ACA, MCA) with development of hypertrophied collateralizing perforators. [1] Affected adults can suffer intraventricular hemorrhages (IVH) from ruptures of hypertrophic collaterals in some cases with formation of a pseudoaneurysm. [2,3] Pseudoaneurysms can be treated conservatively, by microsurgical clipping or endovascular embolization). Endovascular therapy allows easier reach and multiple treatment modalities (coiling, liquid embolization). [4‐7] Methods We present the case of a 44 year old male with Moyamoya disease who suffered a large IVH. Results The patient was brought to the ED after becoming unresponsive. A CT head showed diffuse subarachnoid and intraventricular hemorrhage. CTA revealed extensive Moyamoya disease with prominent hypertrophied ICA‐MCA perforator collaterals and irregular appearance of a right basal ganglia perforator, concerning for pseudoaneurysm. DSA showeda 4.2×3.3 mm pseudoaneurysm of a large hypertrophied perforator originating from the right ICA. A Magic 1.2 microcatheter was used over a 0.007” Hybrid microwire (both Balt, Montmorency, FR) to cannulate the perforator. A mixture of 3 cc of Lipiodol and 1 cc of n‐BCA (N‐butyl‐2‐cyanoacrylate) was injected in the aneurysm with care taken to avoid reflux into in the normal‐appearing portion of the vessel. The aneurysm was excluded from the circulation and post‐operative cone beam CT showed no evidence of large infarction or new intracranial bleeding. After several weeks of neurointensive care, the patient was discharged to rehab. Image description: A. CTA of the head demonstrating diffuse intraventricular hemorrhage (stars) and a spot sign in the territory of the right perforator collaterals concerning for aneurysm. B. DSA of the right internal carotid artery (ICA) demonstrating classic findings of moyamoya disease and a pseudoaneurysm (arrow) at the level of ahypertrophiedICA‐middle cerebral artery perforator collateral. C. Single shot X Ray of the glue cast within the aneurysm and adjacent portions of the vessel. The microcatheter tip is seen at the proximal end of the cast. D. Right ICA DSA after removal of the microcatheter demonstrates exclusion of the aneurysm from the circulation and sparing of adjacent perforator collaterals. Conclusions This abstract illustrates a rare case of pseudoaneurysm formation after rupture of a hypertrophied perforator collateral in a case of severe moyamoya disease. Treatment of these lesions should aim to exclude the aneurysm from the circulation and to preserve as much perforator as possible as these vessels supply normal parench This abstract illustrates a rare case of pseudoaneurysm formation after rupture of a hypertrophied perforator collateral in a case of severe Moyamoya disease. Treatment of these lesions should aim to exclude the aneurysm from the circulation and to preserve as much perforator as possible as these vessels supply normal parenchyma.

Introduction Flow diverters (FDs) have demonstrated a safe and effective profile for the treatment of intracranial aneurysms with complex morphologies and variable anatomic locations. However, aneurysmal persistence after flow diversion still presents in up to 25% of treated aneurysms. Herein, we aimed to perform a pooled analysis of two large studies (SCENT [Surpass Intracranial Aneurysm Embolization System Pivotal Trial to Treat Large or Giant Neck Wide Neck Aneurysms] and SESSIA [Safety and Efficacy of the Surpass Streamline for Intracranial Aneurysms]) to evaluate the predictors of occlusion at final follow‐up after treatment with a 72–96 wire device. Methods We pooled all data from the SCENT (prospective) and SESSIA (retrospective) studies that included patients treated with the Surpass Streamline. From the studies, a subset of patients with unruptured saccular aneurysms located in the internal carotid artery (ICA) up to its terminus were included. The authors collected baseline demographics, comorbidities, aneurysm dimensions, and procedural and follow‐up characteristics for each patient. For our analysis, the outcome was complete aneurysm occlusion, as reported by the studies. We performed a multivariable logistic regression to identify the predictors of complete occlusion. Next, we performed a mediation analysis framework to identify the causal relationship of the predictors with the outcome. Finally, we calculated the predicted probability of occlusion for the continuous predictors. Results A total of 348 patients with 348 aneurysms were included, 394 devices were implanted (1.13 per patient). Median age was 61 [22‐85] years, and 83.6% were females. Hypertension was the most common comorbidity (57%) followed by hyperlipidemia (36%). The ICA paraophthalmic segment was the most common location (45%), followed by the petrocavernous (29%) and supraclinoid (25%). Median aneurysm size was 7.5 [1‐29] mm, and neck size was 4.3 [1‐23] mm. At the final follow‐up, the complete occlusion rate was 73% (255/348). After adjusting for confounders and accounting for collinearity, the multivariable analysis identified aneurysm size (OR 0.89; 95% CI 0.85‐0.93;p< .001), procedural technical events (OR 0.31; 95% CI 0.15‐0.65;p = .002), and first device length (OR 0.98; 95% CI 0.96‐1.00;p = .036) as predictors of complete occlusion. Age had a non‐significant direct effect on complete occlusion (p = .091) but a significant indirect effect mediated through aneurysm size (p< .001) and technical events (p< .02). Using our model, the predicted probability of occlusion is≥ 75% in aneurysms measuring < 10 mm when no technical events are encountered. However, when technical events are encountered, the probability decreases to 50–75%. Conclusions Successful aneurysm occlusion after flow diversion is associated with aneurysm size, procedural technical events, and FD length. Age does not directly affect occlusion, but its influence is mediated through the aneurysm size and technical events. Therefore, a priori knowledge of the patient and aneurysm characteristics might guide FD selection to favor the best treatment outcomes.

Introduction: Flow diversion has established itself as standard treatment of wide complex intracranial aneurysms (IA). Its recognition has been validated with positive occlusion rates and favorable clinical outcomes. The Surpass Streamline (SS) flow diverter (FD) is a braided cobalt/chromium alloy implant with 72 or 96 wires approved by the FDA in 2018. The aim of this study is to determine the safety and efficacy of the SS in a post‐marketing large US cohort. Methods: We performed a multicenter, retrospective study for consecutive patients treated with the SS FD for IA between January 2018 and June 2021 in the United States. Inclusion criteria for participants were: 1. Adults (≥ 18 years) and 2. Treatment with SS FD for IA. Primary safety end point was a major ipsilateral stroke (increase in National Institutes of Health Stroke Scale Score of ≥ 4) or neurological death within 12 months. Primary efficacy was assessed using the 3‐point Raymond‐Roy (RR) occlusion scale on digital subtraction angiography (DSA) at 6‐12‐month follow‐up. Results: A total of 276 patients with 313 aneurysms were enrolled. The median age was 59 years and 199 (72%) were females. The most common comorbidities included hypertension in 156 (57%) subjects followed by hyperlipidemia in 76 (28%) patients. One hundred and twenty‐two (44%) patients were asymptomatic while subarachnoid hemorrhage was present in only 10 (4%) patients. A total of 143 (46%) aneurysms were left‐sided. Aneurysms were located as follows: 274 (88%) were in the anterior circulation with paraophthalmic being the most common in 120 (38%) followed by petrocavernous ICA in 81 (26%); 33 (11%) aneurysms were located in the posterior circulation with basilar trunk being the most common in 14 (5%). The mean maximum aneurysm dome width was 5.77 ± 4.7 mm, neck width 4.22 ± 3.8 mm and dome to neck ratio was 1.63 ± 1.3 mm. The mean number of SS FD implanted per aneurysm was 1.06 (range 1–3) with more than one SS FD implanted in 21 (7%) aneurysms. Modified Rankin Scale (mRS) of 0–2 was present in 206/213 (97%) patients at 6–12 month follow‐up. The complete aneurysm occlusion (RR 1) rate was 145/175 (83%) among subjects who had angiographic follow‐up at 6–12 months. Major stroke and death was encountered in 7 (2%) and 5 (1.8%) of the patients respectively. Conclusions: Our data represent the largest real‐world study using SS FD. These results corroborate its post‐marketing safety and efficacy for the treatment of intracranial aneurysms showing more favorable rates to the initial experience during SCENT trial.

Distal intracranial occlusions can sometimes cause significant neurological deficits. Endovascular thrombectomy in these vessels may improve outcome but carry a higher risk of haemorrhagic complications due to the small calibre and tortuosity of the target vessel. We report two cases of isolated M2/3 artery occlusion causing dense hemiplegia that was successfully treated with stent retrieval thrombectomy. A “semi-deployment technique” of a 3 mm stentriever was employed at the M2/3 bifurcation of the middle cerebral artery. Partial stent unsheathing allowed adequate clot engagement while avoiding excessive tension by the stent metal struts along the tortuous course of a distal vessel. Complete revascularization was achieved after first-pass of the stent retriever without complication, resulting in good clinical outcome in both cases. The described semi-deployment technique reduces the radial and tractional force exerted by the stentreiver on small branches, and may reduce the risk of vessel laceration or dissection in distal vessel thrombectomy.

The Maps of Geohazard features of Southern Sardinia produced in the framework of the Magic project (MArine Geohazard along Italian Coasts) are here presented. The MaGIC project (Marine Geohazard along the Italian Coasts) had the aim of mapping the geohazard in the Italian seas. The features were derived from the digital elevation model interpretation of the seafloor morphology and shallow sub-surface. From the marine geo-hazards point of view, the main critical elements are represented by gravitational mass processes in the canyon heads, some of which, as in the Toro Canyon, are exposed to seismic triggering. In other cases, we observed that gravitational dynamics connected to fluid leakage processes (pockforms). Large landslides and debris avalanches have been detected in Cagliari Gulf, whereas in eastern upper slope, crescent bedforms, occurring in the eastern sector of the upper slope testify to the upward migration of hyperpycnal erosional structures linked to flows from nearby river inputs.

The maps of the geohazard-related features of the North Sardinia continental margin produced by the Magic project (MArine Geohazard along Italian Coasts) are here presented. The maps were created on the base of morphobathymetric data obtained by with multibeam echo sounders. ThreCoNISMa, DSCG Università degli studi di Cagliari, Cittadella Universitaria Monserrato - S.P. Monserrato-Sestu, Monserrato (CA), Italye wide canyon systems, Castelsardo to the west, Lavezzi and Caprera to the east, originate from the continental shelf between the islands of Sardinia and Corsica and run toward the Sardinia Sea and the Tyrrhenian Sea, respectively. The canyons feature very wide and articulated heads, meandered sections of the main axis. The continental shelfhosts several coastal lithotomies, genetically related to late Quaternary sea-level oscillation and coastline migration. Furthermore, in the Bonifacio Strait, several bedform fields testify to the present-day activity of strong bottom currents. The main geohazard potential from the North Sardinia is related to the retreating of Castelsardo canyon heads, in offshore of Castelsardo and Asinara, which cuts the continental shelf reaching a few kilometers from the coast.

ABSTRACTWe present maps of geohazard features identified across north-western Sicily and Pantelleria in the framework of the Magic project (MArine Geohazard along Italian Coasts), which involved Italian marine geological researchers in 2007-2013. These seafloor features were recognized using high-resolution bathymetry data and rely on the morphological expression of the seafloor and shallow sub-surface processes. The north-western Sicily is a complex continental margin, affected by morphodynamic, depositional, and tectonic processes. The Egadi offshore is controlled by fault escarpments and alternating retreating and progradational processes. Ustica and Pantelleria submerged edifices show the effect of volcanic activity. The Ustica seafloor is interested in volcanic, tectonic, and gravitational instability processes, while the Pantelleria offshore underwent erosive-depositional processes and the effect of bottom currents. Two levels of interpretation are represented: the physiographic domain at a scale of 1:250.000 and the morphological units and morpho-bathymetric elements at a 1:100.000 scale.

In this paper, the physiography, geomorphological features, and sedimentary bedforms of the offshore Egadi Islands (Italy) have been illustrated and mapped through an integrated analysis of high-resolution bathymetric, seismo-acoustic, and sedimentological data. The study area is characterized by a wide, up to 25 km, continental shelf which is separated by a NNW-trending linear incision, the Marettimo Channel, along which several erosional and depositional features have been detected and mapped. Sedimentary prograding wedges were detected at water depths between 100–125 m along the shelf margin, which accumulated during the sea-level fall and lowstand stages of the last glacio-eustatic cycle (post- MIS 5.5). This study detected several slope breaks defining scarps across the continental shelf, which were interpreted as coastal cliffs that originated during the post-LGM eustatic sea-level rise. Several fields of different types of sedimentary bedforms, including 2-D and 3-D hydraulic dunes and sorted bedforms, were found across the continental shelf, providing evidence of a high hydrodynamic regime affecting the seafloor. Further on, this study recognized erosive and depositional features related to bottom currents (contourites) in the Marettimo Channel. These findings provide a better understanding of the morpho-sedimentary evolution of the Egadi Islands offshore in the latest Quaternary. Moreover, they offer essential scientific support for effectively managing the most valuable priority habitats for conservation, such as the Posidonia oceanica meadow and coralline algae bioconstructions (Coralligenous habitat).