LAUSR

Dear Editor, Pneumocephalus is defined by the presence of air in the intracranial cavity. This clinical condition is characterized by a sudden, severe headache similar to a thunderclap headache. The air can be identified with neuroradiological techniques such as CT scan or MRI. A 43-year-old female, with a previous history of painful L5-S1 hernia not responsive to the common NSAIDs therapies, was treated with a first ozone therapy cycle. The needle access was by translaminar posterior approach for epidural injection directly in the disc herniation free fragment. A mixture of O2O3 (about 3 cc at 20 Gamma) was injected. For the benefit effects, the patient was submitted to a second ozone therapy cycle: the needle tracking positioning was performed under ultrasound guidance by peridural translaminar approach. The procedure was performed without any dural sac puncture. During the initial phase, any kind of biological fluid such us cerebrospinal fluid or blood did not come out of the needle. Some gas bobbles of ozone with the same CT densitometry value were found in the posterior paravertebral space at the level of needle introduction (Fig. 1a, b). This was viewed by performing lumbar CT exam immediately after the brain study. After this procedure, in addition to the pain reduction, also adverse effects appeared: headache, lasted 4 days, followed by many vomiting episodes. Due to these adverse effects, the patient arrived to the emergency room where a CT scan was performed, and the images showed two pneumocephalus air bubbles above the superior vermian cistern, so the patient came at our attention. The neurologic exam was negative, but the patient declared an important orthostatic headache [1, 2]. After the MRI exam, the presence of the two air bubbles was confirmed (Fig. 2a); the patient was treated with steroids bolus (8 mg/day, dexamethasone), oxygen therapy (5 L/min) for 6 days, and bed rest. Following this therapy, the symptoms were completely solved. Two months later, the MRI exam was repeated and showed disappearance of the two air bubbles (Fig. 2b). Ozone therapy represents a minimally invasive technique proposed to treat disc herniation and radiculopathy: the main indication to act ozone therapy is back pain, with or without radicular pain, which is refractory to 4–6 weeks of conservative therapies. It is proposed sometimes to avoid or delay the open surgical treatment. Ozone exclusion criteria include motor deficits, bone infections, fractures, metastasis, and calcified disc herniation. There is no limit of age. For the treatment of disc herniations, ozone therapy can be given through three techniques: intramuscular (at the level of the lumbar paraspinal muscles), intradiscal, or intraforaminal [3]. The injection is performed with a thin needle image guided by ult rasound, computed tomography, or angiofluoroscopy, and it is completed by periganglionic injection of corticosteroids and anesthetics. This combination gives immediate pain relief and allows time for the ozone to act. Ozone is administrated in a linked formula with oxygen at a very low concentration (20–40 μg/mL of oxygen) avoiding toxic reactions. Ozone therapy shows a multifactorial mechanism of action [3]: