Brainstem cavernous malformation (BSCM)

• Persistent trigeminal artery variant functioning as a duplicate superior cerebellar artery
• QSM predicts haemorrhage risk in brainstem cavernous malformations: a multicentre prospective study
• Outcomes of surgically managed brainstem cavernous Malformations: A systematic review and Meta-Analysis
• Cavernoma of the left ventral striatum, anatomical and microsurgical implications of the ipsilateral transcallosal transrostral pathway
• The role of DTI in surgical management of brainstem cavernous malformations: A meta-analysis of 4159 cases
• Brainstem cavernous malformations: observation, microsurgical resection or stereotactic radiosurgery
• Reply: Brainstem cavernous malformations: observation, microsurgical resection or stereotactic radiosurgery
• Surgical resection of cerebellum cavernous malformation via suboccipital trans-horizontal fissure approach: Two-dimensional video

Symptomatic brainstem cavernous malformations carry a high risk of permanent neurological deficit related to recurrent hemorrhage, which justifies aggressive management. Detailed knowledge of the microscopic and surface anatomy is important for understanding the clinical presentation, predicting possible surgical complications, and formulating an adequate surgical plan ¹⁾.

The natural history of brainstem cavernous malformation is particularly complex.

Medulla Oblongata cavernous malformation…

Rather than developing a grading system for all cerebral cavernous malformations that is weak with BSCMs, Garcia et al. propose a system for the patients who need it most. The BSCM grading system differentiates patients who might expect favorable surgical outcomes and offers guidance to neurosurgeons forced to select these patients ²⁾.

There isn't a standardized classification system for brainstem cavernous malformations that is universally accepted, but they are often classified based on their location within the brainstem and the associated symptoms. Here's a general classification scheme:

Midbrain Cavernomas: Cavernous malformations located within the midbrain, which is the upper part of the brainstem. These can lead to various neurological symptoms depending on their specific location within the midbrain.

Pons Cavernomas: Cavernous malformations located within the pons, which is the middle part of the brainstem. Due to the critical functions of the pons, these cavernomas can cause a wide range of neurological deficits.

Medulla Oblongata Cavernomas: Cavernous malformations located within the medulla oblongata, which is the lower part of the brainstem. These lesions can impact functions such as breathing, heart rate, and other autonomic functions.

Diffuse Brainstem Cavernous Malformations: Some cases involve multiple cavernous malformations dispersed throughout different parts of the brainstem. These can present complex challenges due to the potential for widespread neurological effects.

The classification can also take into account the size of the lesion, the presence of hemorrhage (bleeding), and associated symptoms such as cranial nerve deficits, motor weakness, sensory changes, and others.

Brainstem cavernous malformation diagnosis.

see Brainstem cavernous malformation treatment.

Brainstem cavernous malformation complications.

170 patients were treated with Gamma Knife stereotactic radiosurgery at 11 radiosurgical centers. Hemorrhagic risk reduction, risk factors of post-SRS hemorrhage, and clinical outcomes were retrospectively analyzed. Most patients had single (165/170 patients) brainstem CCMs treated; the majority of CCMs (165/181) presented with bleeding. Using recurrent multivariate analysis, single-session SRS decreased the risk of repeat hemorrhage in patients with hemorrhagic brainstem CCM (HR: 0.17, p < 0.001). The annual hemorrhage rate decreased from 14.8 per 100 CCM-years before SRS to 2.3 after treatment. Using univariate Cox analysis, the probability of new hemorrhages after SRS was reduced for patients older than 35 years (HR = 0.21, p = 0.002) and increased with a margin dose > 13 Gy (HR = 2.57, p = 0.044). Adverse radiation effect (ARE) occurred in 9 patients (5.3%) and was symptomatic in four (2.4%). At a median follow-up of 3.4 years (Inter-quartile range: 5.4), 13 patients (8.0%) had a worsened clinical status, with the treated CCM being the cause in 5.6% (10) of the patients. Single-session SRS decreased the risk of repeat hemorrhage in patients with hemorrhagic brainstem CCM and conveyed this benefit with a low risk of adverse radiation effects (ARE) and worsening clinical status ³⁾.

Brainstem Cavernous Malformation Case Series.

A case of a 42-year-old man with a brainstem cavernous hemangioma presenting with fever of unknown origin and mild headache without meningismus. The patient underwent a midline suboccipital craniectomy and removal of a ruptured brainstem cavernous hemangioma and the surrounding thrombus. Postoperatively, the patient developed left facial nerve palsy, left abducens nerve palsy, and xerostomia. Abducens palsy and xerostomia resolved spontaneously days after the operation. At the 6-month follow-up, the patient showed stable improvement with resolution of his neurological deficits. CONCLUSIONS To our knowledge, there is no reported case of a patient with a ruptured brainstem cavernoma presenting with fever of unknown origin as the main symptom. We assume that the minimal intraventricular hemorrhage triggered the hypothalamic thermoregulating mechanism. Thus, it would be useful for physicians to raise the suspicion of a ruptured brainstem cavernous malformation with further imaging evaluation when investigating fever of unknown origin ⁴⁾.