The management of symptomatic chronic subdural hematoma (CSDH) is surgical evacuation and prognosis in most cases is good. Tension pneumocephalus is the presence of air under pressure in the intracranial cavity. A case of tension pneumocephalus developing as a complication of burr hole evacuation of CSDH is illustrated. In this case, tension pneumocephalus was managed by reopening the wound and saline irrigation with a subdural drain placement. Considering this case report and after a careful review of the literature, the physiopathology, diagnosis, and treatment of this complication are highlighted in the article.

Reversible cerebral vasoconstriction syndrome (RCVS) is characterized by thunderclap headache and intracranial segmental vasoconstriction with or without signs of neurological deficit with a variable course that requires extensive study to prevent complications. The evidence shows RCVS is characterized by being multi-etiological; both the cause and the specific symptoms must be treated to reduce the chance of complications and recurrence. The timely identification of the RCVS and its etiology is the cornerstone of success in managing the disease. New data must be generated to have more efficient resources for the approach to this disease.

The global prevalence of intracranial aneurysms (IA) ranges from 5–10%, with a demographic variation. Large and giant aneurysms typically involve cavernous and paraclinoid segments of the internal carotid artery (ICA), and represent 5% of IA. Typically, these lesions involve segments of the ICA, especially the cavernous and paraclinoid segments. The remaining cases affect the vertebrobasilar region, middle cerebral artery (MCA), and anterior cerebral artery (ACA). From the morphological point of view, they are divided into saccular and fusiform. In cases of rupture, the subarachnoid hemorrhage (SAH) is the most common presentation followed by intracerebral hemorrhage (ICH), or both. Other manifestations can occur as occlusion of perforating vessels, embolic events, seizures, and mass effects. The management of unruptured intracranial aneurysms (UIA) is controversial, and the aim of treatment is to exclude the lesions and preserve neurological function. Endovascular techniques for the treatment of paraclinoid aneurysms, in particular, ICA reconstruction using flow-diverting stents, have become a valid option. However, surgery or endovascular treatment has a number of limitations and the choice of treatment is individual in each case. This type of lesion has an extremely poor natural history, and treatment is a challenge regardless of the technique used.

The report described a clinical case of a 55-year-old female, with a personal history of hypertension, hyperthyroidism, and depressive syndrome. The patient started complaints of moderate-intensity right frontal headache, progressively worsening with two months of evolution. She also reported blurred vision and diplopia. Brain computed tomography (CT) documented a partially calcified sellar and parasellar lesion. Subsequently, magnetic resonance imaging (MRI)/MRI angiographies were performed and showed a saccular aneurysm of the right ICA, cavernous segment. The patient underwent a diagnostic and therapeutic angiography with stent placement. Clinical and imaging improvements were documented by angiography and MRI angiography with progressive reduction of the aneurysm during the period of follow-up.

Delayed cerebral ischemia after subarachnoid hemorrhage is one of the most important causes of mortality and poor functional outcome in patients. Initially, the etiology and treatment of delayed cerebral ischemia focused primarily on cerebral vasospasm. However, recent studies have detected that depolarization, microcirculation, and autoregulation disorder, which spreads together with cerebral vasospasm, also play a role in the etiology. The main treatment strategies in the prevention and treatment of delayed cerebral ischemia are the regulation of blood pressure and the use of calcium channel blockers, especially nimodipine. The main step in the early diagnosis and treatment of the disease is to monitor the neurological clinical status. In addition to transcranial Doppler ultrasonography, computed tomography, or magnetic resonance imaging angiography, continuous electroencephalography and invasive brain multimodal examination may be required in the follow-up period of the disease. In addition to blood pressure regulation, optimization of cardiac output, endovascular interventions, angioplasty, and/or intra-arterial vasodilator infusion are other treatment methods. This review aimed to evaluate delayed cerebral ischemia, one of the most important complications of subarachnoid hemorrhage, in the light of current literature.

The glymphatic system, or glial-lymphatic system, is a waste clearance system composed of perivascular channels formed by astrocytes that mediate the clearance of proteins and metabolites from the brain. These channels facilitate the movement of cerebrospinal fluid throughout brain parenchyma and are critical for homeostasis. Disruption of the glymphatic system leads to an accumulation of these waste products as well as increased interstitial fluid in the brain. These phenomena are also seen during and after subarachnoid hemorrhages (SAH), contributing to the brain damage seen after rupture of a major blood vessel. Herein this review provides an overview of the glymphatic system, its disruption during SAH, and its function in recovery following SAH. The review also outlines drugs which target the glymphatic system and may have therapeutic applications following SAH.

Subarachnoid hemorrhage (SAH) has deleterious outcomes for patients, and during the hospital stay, patients are susceptible to vasospasm and delayed cerebral ischemia. Coronavirus disease 2019 (COVID-19) has been shown to worsen hypertension through angiotensin-converting enzyme 2 (ACE2) activity, therefore, predisposing to aneurysm rupture. The classic renin-angiotensin pathway activation also predisposes to vasospasm and subsequent delayed cerebral ischemia. Matrix metalloproteinase 9 upregulation can lead to an inflammatory surge, which worsens outcomes for patients. SAH patients with COVID-19 are more susceptible to ventilator-associated pneumonia, reversible cerebral vasoconstriction syndrome, and respiratory distress. Emerging treatments are warranted to target key components of the anti-inflammatory cascade. The aim of this review is to explore how the COVID-19 virus and the intensive care unit (ICU) treatment of severe COVID can contribute to SAH.