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Dear Editor, The middle meningeal artery (MMA) has been proposed to play a crucial role in thermoregulation, which is essential for maintaining intracranial homeostasis [Figure 1]. This function is particularly important in patients with neurotrauma, as highlighted in Falk’s “radiator” theory.[1] Traumatic brain injury (TBI) often leads to secondary brain injury, where underlying physiological processes, including vascular function and temperature regulation, significantly influence outcomes. Understanding the role of the MMA can help speculate on how its potential alterations might be linked to clinical outcomes in patients with neurotrauma. Falk’s theory suggests that the MMA serves as a key player in regulating brain temperature, an effect amplified by the bipedal posture that results in increased cranial heat.[2] The MMA acts as a vascular radiator, allowing for heat dissipation and helping maintain stable brain temperatures, especially in the face of increased metabolic demands associated with brain activity. This is critical because brain tissue is highly sensitive to temperature changes, and even slight elevations in temperature can exacerbate neuronal damage, particularly in TBIs.Figure 1: The middle meningeal artery as a central player in thermoregulation within the brainThe role of the MMA in neurotrauma has been extensively recognized, but in contrast, the pathophysiological concepts are few understood.[3] In neurotrauma, especially in cases of TBI or in endovascular neurosurgery, dural arteriovenous fistulas (DAVFs), the MMA’s function becomes a central point of interest. The MMA supplies blood to both the meninges and parts of the skull, and its disruption can alter intracranial hemodynamics. Since it is involved in the cerebral circulation, any damage or obliteration of this artery – whether from trauma, surgical intervention, or a vascular anomaly – may disturb cerebral perfusion and lead to secondary injury. Other research suggests that the meningeal vascular network is unlikely to serve a thermoregulatory role in normal adult blood flow conditions, yet its potential biomechanical functions, such as acting as a hydraulic skeleton for shock absorption, remain plausible.[4] Regarding the temperature regulation and the impact on brain injury, the thermoregulatory function of the MMA becomes even more relevant in the setting of neurotrauma. Brain injuries lead to increased metabolic activity, raising the brain’s temperature. A dysfunctional MMA may impair heat dissipation, leading to elevated temperatures that can worsen injury. In this regard, the MMA may serve as a natural buffer, limiting the extent of neuronal damage by assisting in the regulation of intracranial temperature.[5] Regarding the temperature regulation and the impact on brain injury, the thermoregulatory function of the MMA becomes even more relevant in the setting of neurotrauma. Brain injuries lead to increased metabolic activity, raising the brain’s temperature. A dysfunctional MMA may impair heat dissipation, leading to elevated temperatures that can worsen injury. In this regard, the MMA may serve as a natural buffer, limiting the extent of neuronal damage by assisting in the regulation of intracranial temperature. On the other hand, compensatory mechanisms in the context of dural fistulas, DAVFs are a common vascular complication following trauma.[6] In these conditions, the MMA can be a compensatory mechanism, helping to alleviate the hemodynamic disturbances caused by abnormal venous drainage and maintaining intracranial pressure (ICP). This idea of compensation is in line with the “radiator” theory, where the MMA’s vascular properties extend beyond simple circulation to include regulating ICP and cerebral blood flow in the face of pathological conditions. Another one is secondary brain injury which involves further damage after the initial trauma and is one of the leading causes of poor outcomes in neurotrauma. Adequate control of temperature is one of the key factors in mitigating the secondary injury.[7] Exploring the role of the MMA in thermoregulation could provide an avenue for new clinical interventions to regulate brain temperature through the use of targeted temperature management or hypothermic therapies. Because MMA keeps appropriate hemodynamic compensation and thermoregulation, it may be worthwhile to consider ways that might help preserve MMA function in neurotrauma patients. In the context of surgery, the attempt to either avoid involving the MMA or effectively minimize MMA disruption during craniectomies or surgical repairs of skull fractures may enhance postoperative recovery and decrease complications associated with ICP management. Whether pharmacologically or mechanically, thinking of ways that may be employed to modulate MMA function – either enhancing the compensatory properties of the MMA or improving its thermoregulatory properties – offers hope for substantial improvement in neurotrauma outcomes. Enhancing vascular tone or diminishing inflammatory responses within the MMA may reduce secondary brain injury and prevent further brain injury while optimizing brain perfusion and temperature control. The “radiator” theory postulates that the MMA plays a significant role in regulating brain temperature and compensating for hemodynamic disruption, both elements that are critical for the context of neurotrauma. The implication of this theory will add greater insight into the pathophysiology of the TBI, ICP management, and general thermoregulatory mechanisms which may influence outcomes in patients suffering from neurotrauma [Figure 2]. Further study on the role played by the MMA in hemodynamics and temperature regulation could foster new therapeutic targets directed to these mechanisms to support care and recovery in TBI patients.Figure 2: The middle meningeal artery’s thermoregulatory and hemodynamic roles influence outcomes in traumatic brain injury. MMA: Middle meningeal arteryFinancial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.