Aerospace Implications of Key Neurological Conditions.

INTRODUCTION: The neurological impact (or lack thereof) of certain medical histories and imaging findings is important to understand in the context of air and spaceflight. There are a number of neurological conditions that, if present in pilots and astronauts, carry variable (and sometimes adverse) functional implications for safety and overall mission success. In this systematic overview, the authors will refer to the relevant clinical and radiological features of brain tumors and vascular anomalies, cerebral edema and intracranial hypertension, concussion and the traumatic brain injury (TBI) spectrum, hematomas, cerebrospinal fluid circulation anomalies including hydrocephalus and sequestrations, spinal degenerative changes, and cerebral ischemia and demyelination. It is notable that these last two conditions have recently been reported to be a complication in some people with coronavirus disease 2019 (COVID-19). A paradigm for practical neurological workup of symptomatic pilots and astronauts will be discussed, as will the controversial notion of pre-emptive radiological screening (vs. not screening) in asymptomatic or clinically occult situations. The concepts of medical surveillance in the setting of known or diagnosed pathologies, and expert panel review and simulator and flight checks in complex neurological cases, are also elaborated on in this paper. We believe this overview will contribute toward the enhancement of a broad understanding of neurological conditions, their clinical workup, and their precautionary management in the setting of aviation and aerospace.Khurana VG, Jithoo R, Barnett M. Aerospace implications of key neurological conditions. Aerosp Med Hum Perform. 2021; 92(2):113119.

Cryptococcal meningitis causing obstructive hydrocephalus in a patient on fingolimod.

Cryptococcosis is a recognised opportunistic infection in immunocompromised patients. The long-term adverse effect profile of fingolimod, an immunomodulating agent approved for use in multiple sclerosis in 2010, is only just emerging. We report the first case to our knowledge of a patient presenting with obstructive hydrocephalus secondary to cryptococcal meningitis in the setting of fingolimod therapy. Extensive posterior fossa leptomeningeal inflammation with associated cerebellar oedema resulted in effacement of the fourth ventricle and obstructive hydrocephalus requiring urgent ventriculostomy. Induction, consolidative and maintenance antifungal therapy was prescribed and subsequent conversion to a ventriculoperitoneal shunt was successful in relieving the patient's ventriculomegaly. Awareness of these rare, novel and life-threatening complications of fingolimod-associated immunocompromise is critical as the use of such drugs is expected to rise.

Spontaneous spinal epidural haematoma in a geriatric patient on aspirin.

Spontaneous spinal epidural haematoma (SSEH) is a rare cause of spinal cord compression in adults, especially in the elderly. We report an independent 88-year-old female, on aspirin only for chronic atrial fibrillation, who presented with a 12-hour history of acute lumbar back pain, urinary incontinence and progressive bilateral lower limb paresis. Examination revealed saddle anaesthesia and reduced anal tone. Urgent spinal MRI demonstrated an epidural haematoma extending from T7 to L5. The patient made a poor initial post-operative recovery, but four months later had begun to mobilise independently after intensive physiotherapy. The case highlights the significance of clinical suspicion, especially in those patients on anti-platelet therapy, rapid spinal radiography and emergent decompressive surgery in SSEH patients, as well as the importance of ongoing rehabilitation in restoring neurological function.

Spinal cord compression as the initial presentation of acute biphenotypic leukaemia.

Acute biphenotypic leukaemia (BAL) is an uncommon haematological malignancy with features of myeloid and lymphoid origin and poor overall prognosis. We report a 68-year-old man who presented with rapidly progressive upper thoracic spinal cord compression secondary to an extradural lesion. A T2-3 decompressive laminectomy with tumour excision was performed. Histopathology confirmed the diagnosis of acute biphenotypic (B/myeloid) leukaemia. The patient had only minor post-operative improvement in pyramidal lower limb weakness. He succumbed to the disease three months post-diagnosis after failing induction chemotherapy. While central nervous system involvement with acute leukaemia is well recognised, this is the first reported patient with spinal cord compression secondary to this leukaemia subtype.

Sacral ganglioneuroma in a 19-year-old woman.

Ganglioneuroma is a rare benign neural crest tumour, located usually in the posterior mediastinum and retroperitoneum. It tends to acquire significant size before symptoms or clinical signs become apparent. We report a 19-year-old female who underwent excision of a pelvisacral ganglioneuroma via a Pfannenstiel incision, after an abdominopelvic CT scan for investigation of left iliac fossa pain and menorrhagia detected a pelvic mass. This report highlights the importance of complete surgical excision of these lesions and the collaboration of multiple surgical units in managing these often large, variably located tumours.