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In this work we back-analyze two landslide failures that occurred in the Northern Apennines of Italy, in terms of surface movements and their relation with rainfalls. The two landslides have some similarities in that they are historical earthflows characterized by relatively long period of slow-moving stable sliding that can be interrupted by rapid acceleration and catastrophic failure. In both cases, the catastrophic failures were sudden and unexpected, causing problems to infrastructures (roads and railways) located at the toe of the landslides. We process interferograms of SAR images acquired by Sentinel 1 A/B with time spans ranging from 6 to 24 days, removing those having low coherence by manual inspection. The conventional 2-pass technique allowed us to obtain measurements of surface displacement despite the fact that no infrastructures nor major reflectors are present on landslide bodies. Our interferograms show that surface displacements are well visible since 2015. They display nearly continuous downslope motion with seasonal velocity changes. Time series between 2015 and 2018 shows that surface displacements can be appreciated throughout most part of the year with snow cover and summer peak of vegetation being the most notable exceptions. Distinct accelerations can be detected in space and time during the weeks and months preceding the catastrophic failures. We compare time-dependent deformations to precipitation patterns to explore interactions between precipitation and landslide kinematics and to document the transition from stable to unstable sliding. Our work indicate that InSAR interferometry can be successfully used to anticipate catastrophic failures.

The objective of this study is to analyse the complications of orbital decompression in Graves' orbitopathy. The clinical records of 946 patients who had been operated on with orbital decompression for Graves' orbitopathy were reviewed and the intra- and post-operative complications with minimum follow-up of six months were analysed. An extensive review of the literature was carried out to compare results. In the case-series reported here the most frequent complications were: wasting of the temporal region (100%) in patients operated on using a coronal approach; permanent hypoesthesia of V2 (13%) and V1 (8%) in patients operated on with an upper eyelid incision. In only one patient was a total monolateral lesion of V2 reported. The most severe complications consisted in reduction of visual acuity in 5 patients, and CSF leak with cerebral complications in 2 patients, who were operated on with a non-endoscopic endonasal approach. Three patients had intra-operative haemorrhages and 3 patients had post-operative haemorrhages requiring further surgical intervention. The incidence of symptomatic sinusitis/mucoceles was 0.75%. In conclusion, orbital decompression carried out with endoscopic endonasal technique and via transpalpebral accesses appears to be associated with a low incidence of complications. Knowledge of the causes of the possible complications in the different surgical approaches can definitely help to reduce their incidence.L’obiettivo di questo studio è analizzare le complicanze della decompressione orbitaria in pazienti affetti da oftalmopatia Basedowiana. Abbiamo analizzato 946 pazienti sottoposti a decompressione orbitaria per orbitopatia di Graves e le complicanze intra- e post-operatorie con un follow-up minimo di 6 mesi. Abbiamo eseguito inoltre un’estesa revisione della letteratura per comparare i risultati. Nel nostro studio le più frequenti complicanze sono state: atrofia della regione temporale (100%) nei pazienti sottoposti a decompressione con approccio coronale; ipoestesia permanente di V2 (13%) e V1 (8%) in pazienti sottoposti a decompressione con approccio transpalpebrale superiore. Un solo paziente ha avuto una lesione totale monolaterale di V2. Le complicanze più gravi sono state la riduzione dell’acuità visiva, che si è verificata in 5 pazienti, e la perdita di liquido cerebrospinale con complicanze cerebrali, verificatesi in 2 pazienti, entrambi operati con approccio endonasale non endoscopico. 3 pazienti hanno avuto un’emorragia intraoperatoria mentre 3 pazienti un’emorragia postoperatoria che ha richiesto un secondo intervento chirurgico. L’incidenza delle sinusiti/mucoceli sintomatici è stata dello 0,75%. In conclusione abbiamo evidenziato come la decompressione orbitaria eseguita con tecnica endoscopica endonasale e con accessi transpalpebrali sia una procedura chirurgica con una bassa incidenza di complicanze. La conoscenza delle cause delle possibili complicanze nei differenti approcci chirurgici può sicuramente aiutare a ridurre la loro incidenza.