Background and Purpose According to WHO statistics, approximately 6.9 billion people worldwide had been vaccinated against SARS-CoV-2 as at October 27, 2021, including around 1.0 billion people in India. Most Indian recipients received the Covishield (ChAdOx1-S/nCoV-19) vaccine, followed by the Covaxin (an inactivated SARS-CoV-2 antigen) vaccine. This study was conducted to characterize the neurological phenotypic spectrum of patients with adverse events following immunization with any of the available COVID-19 vaccines in India (Covishield or Covaxin) during the study period and their temporal relationship with vaccination. Methods This ambispective multicenter hospital-based cohort study covered the period from March to October 2021. The study included all cases suspected of having neurological complications following COVID-19 vaccination. Results We report a spectrum of serious postvaccination neurological complications comprising primary central nervous system demyelination (4 cases), cerebral venous thrombosis (3 cases), Guillain-Barre syndrome (2 cases), vaccine-induced prothrombotic immune thrombocytopenia syndrome (2 cases), cranial nerve palsies (2 cases), primary cerebral hemorrhage (1 case), vestibular neuronitis (1 case), chronic inflammatory demyelinating polyneuropathy (1 case), generalized myasthenia (1 case), and seizures (1 case). Conclusions Although the benefits of vaccination far outweigh its risks, clinicians must be aware of possible serious adverse events associated with COVID-19 vaccinations.

Spontaneous intracranial hypotension (SIH) is a rare disorder that occurs secondary to acquired cerebrospinal fluid (CSF) leaks in the spine. Treatment involves either an epidural blood patch or surgical ligation. Essential to the selecting the optimal management strategy is classifying the type of leak and accurate localization of its level. Hitherto, this has been achieved using conventional imaging methods such as static CT or MR myelography which are adequate for the demonstration of only high flow leaks. Digital subtraction myelography (DSM) is a novel technique which provides superior temporal and spatial resolution in the localization of more challenging slow flow leaks. However, DSM may also be initially non-diagnostic. We report a case of SIH in which repeat DSM revealed a type 3 CSF-venous fistula and demonstrate a possible mechanism of transient CSF leak block resulting in the initial false negative findings based on morphological changes in the culprit nerve sheath diverticulum-pseudomeningocoele complex. The patient underwent successful surgical ligation with clinicoradiological resolution of SIH.