====== Intracranial epidural abscess ====== //J.Sales-Llopis// //Neurosurgery Service, Alicante University General Hospital, Alicante Institute for Health and Biomedical Research (ISABIAL - FISABIO Foundation), Alicante, Spain.// ---- Intracranial [[epidural abscess]], less commonly called [[epidural empyema]], refers to a pyogenic collection within the [[epidural space]] of the head. ===== History ===== Intracranial [[epidural abscess]] was first described in [[1760]] by Sir [[Percivall Pott]]. Pott also documented the associated [[scalp]] swelling, the so-called [[Pott’s puffy tumor]]. ===== Epidemiology ===== [[Intracranial epidural abscess epidemiology]] ===== Risk Factors ===== Epidural abscesses occur as a result of infections involving the spinal or cranial epidural space. Intracranial epidural abscesses (IEA) are complications of cranial surgery or trauma; they may also complicate otorhinolaryngological infections or other neck and thoracic procedures ((Akhondi H, Baker MB. Epidural Abscess. 2022 Jan 19. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan–. PMID: 30571071.)). ---- Acute [[frontal sinusitis]] can be a serious condition because of its potential life-threatening [[complications]]. These complications, including spread of infection to the frontal bone and intracranially, require prompt diagnosis and intervention to avoid morbidity and mortality ((Wang WH, Hwang TZ. Extensive subgaleal abscess and epidural empyema in a patient with acute frontal sinusitis. J Formos Med Assoc. 2003 May;102(5):338-41. PubMed PMID: 12874674. )). ---- Another significant cause is mastoiditis which accounts as the cause in approximately 20% of cases. Epidural abscesses can also occur as a result of trauma, epidural injections or anesthesia, open head or spinal trauma, neurosurgery or meningitis. ===== Clinical features ===== Usually, the patient presents with [[headache]] that is either diffuse or localized to one side with [[scalp]] [[tenderness]]. Headache may be the only presenting symptom. The patient may have persistent fever that develops during or after treatment for sinus or middle ear infection. Purulent discharge from the ears or sinuses, periorbital swelling, and brawny edema of the scalp might accompany. Because the epidural abscess usually enlarges slowly, the following signs do not develop until the infection has reached the subdural space, resulting in subdural empyema, at which time the patient might present with neck stiffness, nausea, vomiting, lethargy, and hemiparesis. Seizures might very well be the first presenting symptom in some cases. Symptoms and signs of increased intracranial pressure (ICP) include nausea, vomiting, and papilledema. Rarely, when the epidural abscess develops near the petrous bone and involves the fifth and sixth cranial nerves, the patient may present with ipsilateral facial pain and weakness of the lateral rectus muscle (ie, the so-called Gradenigo syndrome). Many times, scalp cellulitis, sinusitis, or skull fracture may draw the attention of the physician to such an extent that the diagnosis of epidural abscess may be missed. One should consider the diagnosis of intracranial epidural abscess when a patient presents with unresolving frontal sinus symptoms. Also consider this diagnosis in patients with new neurologic symptoms after trauma or cranial surgery, even if months or years have elapsed since operation or trauma. Onset can be acute, especially in patients without any history of previous cranial neurosurgery. They often present with acute symptoms of encephalopathy and focal neurological deficits. ===== Pathology ===== The most commonly isolated pathogens are [[Streptococcus pneumoniae]], [[Haemophilus influenzae]], [[Staphylococcus aureus]] and [[Staphylococcus epidermidis]]. In more than two-thirds of cases, an epidural abscess is a complication of [[sinusitis]]. Seeding can be via direct invasion through the sinus walls or hematogenous seeding through retrograde valveless [[bridging vein]]s. ===== Diagnosis ===== ==== CT ==== Less sensitive for the detection of epidural abscess compared to MRI. Features on CT include: extra-axial location isodense or hypodense to surrounding brain biconvex shape usually do not cross suture lines may cross the midline strong peripheral enhancement with contrast ==== Contrast-enhanced MRI ==== Diagnosis of epidural abscess or subdural empyema is by contrast-enhanced MRI or, if MRI is not available, by contrast-enhanced CT. Blood and surgical specimens are cultured aerobically and anaerobically. Characteristics on MRI include: T1: hyperintense T1 C+ (Gd): strong peripheral contrast enhancement T2/FLAIR: isointense or hyperintense PD: isointense or hyperintense DWI: area of restricted diffusion ==== Lumbar puncture ==== Provides little useful information and may precipitate [[transtentorial herniation]]. If intracranial epidural abscess or subdural empyema is suspected (eg, based on symptom duration of several days, focal deficits, or risk factors) in patients with meningeal signs, lumbar puncture is contraindicated until neuroimaging excludes a mass lesion. ===== Complications ===== Epidural abscess may extend into the subdural space to cause [[subdural empyema]]. Both epidural abscess and subdural empyema may progress to [[meningitis]], cortical [[venous thrombosis]], or [[brain abscess]]. Subdural empyema can rapidly spread to involve an entire cerebral hemisphere. ===== Treatment ===== [[Intracranial epidural abscess treatment]]. ===== Case reports ===== An 11-year-old child, presenting with a two-week-long history of an acute otitis badly treated. Admitted for headaches, fever, vomiting and left eyelid swelling. The preoperative CT scan revealed a left frontal epidural abscess associated to a sub-periosteal Abscess. The patient was operated on. A supraorbital incision through the eyebrows allowed the evacuation of the periorbital abscess and the cerebral empyema through a trephine hole. The patient received probabilistic intravenous antibiotic therapy with ceftriaxon, aminoglycoside and metronidazole. Then relay per os. Postoperative recovery was marked by disappearance of headaches at postoperative Day two and the periorbital edema at day six. The patient was discharged home at postoperative week four with oral antibiotic therapy. Three months postoperative months follow-up CT scan revealed a total radiological cleaning. Otogenic frontal abscess associated to orbital Abscess is extremely rare and should be considered in front of ophthalmological signs. The management is multidisciplinary, and the entry point treatment mustn't be forgotten ((Laaidi A, Makhchoune M, Tahrir Y, Haouas MY, Naja A, Lakhdar A. Simultaneous frontal and orbital abscess rare complications of otogenic origin: Case report and literature review. Ann Med Surg (Lond). 2022 Mar 7;75:103458. doi: 10.1016/j.amsu.2022.103458. PMID: 35386769; PMCID: PMC8977935.)). ==== 2021 ==== A pediatric patient with chronic hematopoiesis and thick double periosteal layers who developed an epidural pus collection after epidural hematoma evacuation. This article highlights the importance of detecting complications from epidural hematoma evacuation, including intracranial abscess and pus formation. Therefore, it is crucial to treat such cases meticulously ((Shaabi A, Moshref RH. Epidural Abscess Following Epidural Evacuation in a Patient With Ventriculoperitoneal Shunt: A Case Report. Cureus. 2021 Oct 29;13(10):e19134. doi: 10.7759/cureus.19134. PMID: 34868772; PMCID: PMC8627705.)). ====1996==== A case of intracranial epidural abscess, 20 years after allograftic cranioplasty was presented. The abscess was caused by bacterial implantation after a minor stab wound of the scalp over the cranioplastic plate. It seemed quite rare that the intarcranial abscess occurred 20 years after an allograftic cranioplasty ((Morioka T, Fujiwara S, Akimoto T, Nishio S, Fukui M. Intracranial epidural abscess: late complication of allograft cranioplasty. Fukuoka Igaku Zasshi. 1996 Feb;87(2):57-9. PubMed PMID: 8851369. )). ==== Database ==== o Cranial surgery o Trauma o Otorhinolaryngological infections 0 Neck or thoracic procedures o Mastoiditis o Meningitis. ---- o Headache