Five-step unilateral biportal endoscopic surgery for central lumbar canal stenosis: "Z" technique nuance.

The treatment for lumbar spinal stenosis has advanced through the use of minimally invasive surgery techniques. Endoscopic methods go even further, with studies showing that both uniportal and biportal endoscopic techniques have outcomes comparable to traditional approaches. However, there is limited knowledge of the step-by-step decompression process when using the unilateral biportal endoscopic (UBE). To address this, the authors introduce the five steps in the "Z" sequence, which aims to reduce surgical time and complications. The video can be found here: https://stream.cadmore.media/r10.3171/2024.1.FOCVID23182.

Endovascular treatment of a pial arteriovenous fistula with occipital remodeling secondary to giant torcular dilation.

Intracranial arteriovenous fistulas are vascular malformations in which clinical suspicion and prompt diagnosis, with a subsequent appropriate therapeutic approach, are crucial to avoid the development of irreversible neurological damage or even patient death because these lesions can be associated with heavy bleeding and high mortality rates. The authors present the case of a direct pial arteriovenous fistula in an infant and its unusual presentation as a large occipital protuberance with hard consistency and an audible murmur that produced bone remodeling. The patient was successfully treated by endovascular therapy, with complete regression of the occipital protuberance during follow-up.

Urbanisation and flood vulnerability in the peri-urban interface of Mexico City.

Chronic flooding in the Chalco valley, state of Mexico, Mexico, is the outcome of past and present socio-environmental changes which have taken place in Mexico City's south-eastern peri-urban interface. This flooding is the result of a complex interaction between urbanisation in an ex-lacustrine area, permanent ecological deterioration and ground subsidence, poor sanitation and inadequate policy responses. Far from solving the flooding problem, short-term policy responses have created increasingly unsafe conditions for current residents. A socio-historical analysis of disasters reveals the importance of taking into consideration particular social actors and institutions in hazard generation and flood vulnerability over time. This paper analyses three aspects of this flooding: first, the importance of approaching floods from a socio-historical perspective; second, the relation between urbanisation, former policies and flood risk generation; and third, current policy responses to and the failure in the risk management of La Compañía Canal.