Brain Abscess: A circumscribed collection of purulent exudate in the brain, due to bacterial and other infections. The majority are caused by spread of infected material from a focus of suppuration elsewhere in the body, notably the PARANASAL SINUSES, middle ear (see EAR, MIDDLE); HEART (see also ENDOCARDITIS, BACTERIAL), and LUNG. Penetrating CRANIOCEREBRAL TRAUMA and NEUROSURGICAL PROCEDURES may also be associated with this condition. Clinical manifestations include HEADACHE; SEIZURES; focal neurologic deficits; and alterations of consciousness. (Adams et al., Principles of Neurology, 6th ed, pp712-6)Abscess: Accumulation of purulent material in tissues, organs, or circumscribed spaces, usually associated with signs of infection.Liver Abscess: Solitary or multiple collections of PUS within the liver as a result of infection by bacteria, protozoa, or other agents.Abdominal Abscess: An abscess located in the abdominal cavity, i.e., the cavity between the diaphragm above and the pelvis below. (From Dorland, 27th ed)Lung Abscess: Solitary or multiple collections of PUS within the lung parenchyma as a result of infection by bacteria, protozoa, or other agents.Nocardia Infections: Infections with bacteria of the genus NOCARDIA.Epidural Abscess: Circumscribed collections of suppurative material occurring in the spinal or intracranial EPIDURAL SPACE. The majority of epidural abscesses occur in the spinal canal and are associated with OSTEOMYELITIS of a vertebral body; ANALGESIA, EPIDURAL; and other conditions. Clinical manifestations include local and radicular pain, weakness, sensory loss, URINARY INCONTINENCE, and FECAL INCONTINENCE. Cranial epidural abscesses are usually associated with OSTEOMYELITIS of a cranial bone, SINUSITIS, or OTITIS MEDIA. (From Adams et al., Principles of Neurology, 6th ed, p710 and pp1240-1; J Neurol Neurosurg Psychiatry 1998 Aug;65(2):209-12)Psoas Abscess: Abscess of the PSOAS MUSCLES resulting usually from disease of the lumbar vertebrae, with the pus descending into the muscle sheath. The infection is most commonly tuberculous or staphylococcal.Liver Abscess, Amebic: Single or multiple areas of PUS due to infection by any ameboid protozoa (AMEBIASIS). A common form is caused by the ingestion of ENTAMOEBA HISTOLYTICA.Suppuration: A pathologic process consisting in the formation of pus.Citrobacter koseri: A species of gram-negative enterobacteria found in WATER; SEWAGE; SOIL; and FOOD. It can be present in any clinical specimen as an opportunistic pathogen.Central Nervous System Fungal Infections: MYCOSES of the brain, spinal cord, and meninges which may result in ENCEPHALITIS; MENINGITIS, FUNGAL; MYELITIS; BRAIN ABSCESS; and EPIDURAL ABSCESS. Certain types of fungi may produce disease in immunologically normal hosts, while others are classified as opportunistic pathogens, causing illness primarily in immunocompromised individuals (e.g., ACQUIRED IMMUNODEFICIENCY SYNDROME).Tuberculoma, Intracranial: A well-circumscribed mass composed of tuberculous granulation tissue that may occur in the cerebral hemispheres, cerebellum, brain stem, or perimeningeal spaces. Multiple lesions are quite common. Management of intracranial manifestations vary with lesion site. Intracranial tuberculomas may be associated with SEIZURES, focal neurologic deficits, and INTRACRANIAL HYPERTENSION. Spinal cord tuberculomas may be associated with localized or radicular pain, weakness, sensory loss, and incontinence. Tuberculomas may arise as OPPORTUNISTIC INFECTIONS, but also occur in immunocompetent individuals.Liver Abscess, Pyogenic: Single or multiple areas of PUS due to bacterial infection within the hepatic parenchyma. It can be caused by a variety of BACTERIA, local or disseminated from infections elsewhere such as in APPENDICITIS; CHOLECYSTITIS; PERITONITIS; and after LIVER TRANSPLANTATION.Brain Neoplasms: Neoplasms of the intracranial components of the central nervous system, including the cerebral hemispheres, basal ganglia, hypothalamus, thalamus, brain stem, and cerebellum. Brain neoplasms are subdivided into primary (originating from brain tissue) and secondary (i.e., metastatic) forms. Primary neoplasms are subdivided into benign and malignant forms. In general, brain tumors may also be classified by age of onset, histologic type, or presenting location in the brain.Focal Infection, Dental: Secondary or systemic infections due to dissemination throughout the body of microorganisms whose primary focus of infection lies in the periodontal tissues.Drainage: The removal of fluids or discharges from the body, such as from a wound, sore, or cavity.Tuberculosis, Central Nervous System: Tuberculosis of the brain, spinal cord, or meninges (TUBERCULOSIS, MENINGEAL), most often caused by MYCOBACTERIUM TUBERCULOSIS and rarely by MYCOBACTERIUM BOVIS. The infection may be limited to the nervous system or coexist in other organs (e.g., TUBERCULOSIS, PULMONARY). The organism tends to seed the meninges causing a diffuse meningitis and leads to the formation of TUBERCULOMA, which may occur within the brain, spinal cord, or perimeningeal spaces. Tuberculous involvement of the vertebral column (TUBERCULOSIS, SPINAL) may result in nerve root or spinal cord compression. (From Adams et al., Principles of Neurology, 6th ed, pp717-20)Suction: The removal of secretions, gas or fluid from hollow or tubular organs or cavities by means of a tube and a device that acts on negative pressure.Brain Chemistry: Changes in the amounts of various chemicals (neurotransmitters, receptors, enzymes, and other metabolites) specific to the area of the central nervous system contained within the head. These are monitored over time, during sensory stimulation, or under different disease states.Streptococcus intermedius: A species of gram-positive bacteria in the STREPTOCOCCUS MILLERI GROUP. It is commonly found in the oropharynx flora and has a proclivity for abscess formation, most characteristically in the CENTRAL NERVOUS SYSTEM and LIVER.Magnetic Resonance Imaging: Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.Bacillaceae Infections: Infections with bacteria of the family BACILLACEAE.Fusobacterium Infections: Infections with bacteria of the genus FUSOBACTERIUM.Periapical Abscess: Acute or chronic inflammation of tissues surrounding the apical portion of a tooth, associated with the collection of pus, resulting from infection following pulp infection through a carious lesion or as a result of an injury causing pulp necrosis. (Dorland, 27th ed)Retropharyngeal Abscess: An accumulation of purulent material in the space between the PHARYNX and the CERVICAL VERTEBRAE. This usually results from SUPPURATION of retropharyngeal LYMPH NODES in patients with UPPER RESPIRATORY TRACT INFECTIONS, perforation of the pharynx, or head and neck injuries.Craniotomy: Any operation on the cranium or incision into the cranium. (Dorland, 28th ed)Brain Injuries: Acute and chronic (see also BRAIN INJURIES, CHRONIC) injuries to the brain, including the cerebral hemispheres, CEREBELLUM, and BRAIN STEM. Clinical manifestations depend on the nature of injury. Diffuse trauma to the brain is frequently associated with DIFFUSE AXONAL INJURY or COMA, POST-TRAUMATIC. Localized injuries may be associated with NEUROBEHAVIORAL MANIFESTATIONS; HEMIPARESIS, or other focal neurologic deficits.Tomography, X-Ray Computed: Tomography using x-ray transmission and a computer algorithm to reconstruct the image.Brain: The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.Peritonsillar Abscess: An accumulation of purulent material in the area between the PALATINE TONSIL and its capsule.Frontal Sinusitis: Inflammation of the NASAL MUCOSA in the FRONTAL SINUS. In many cases, it is caused by an infection of the bacteria STREPTOCOCCUS PNEUMONIAE or HAEMOPHILUS INFLUENZAE.Telangiectasia, Hereditary Hemorrhagic: An autosomal dominant vascular anomaly characterized by telangiectases of the skin and mucous membranes and by recurrent gastrointestinal bleeding. This disorder is caused by mutations of a gene (on chromosome 9q3) which encodes endoglin, a membrane glycoprotein that binds TRANSFORMING GROWTH FACTOR BETA.Streptococcus milleri Group: A subset of VIRIDANS STREPTOCOCCI, but the species in this group differ in their hemolytic pattern and diseases caused. These species are often beta-hemolytic and produce pyogenic infections.Gemella: A genus that has been reclassified into BACILLALES incertae sedis because of its ambiguous taxonomy. Previously it was considered part of the Staphylococcaceae family.Nocardia: A genus of gram-positive, aerobic bacteria whose species are widely distributed and are abundant in soil. Some strains are pathogenic opportunists for humans and animals.Anti-Bacterial Agents: Substances that reduce the growth or reproduction of BACTERIA.Brain Mapping: Imaging techniques used to colocalize sites of brain functions or physiological activity with brain structures.Empyema: Presence of pus in a hollow organ or body cavity.Neuroaspergillosis: Infections of the nervous system caused by fungi of the genus ASPERGILLUS, most commonly ASPERGILLUS FUMIGATUS. Aspergillus infections may occur in immunocompetent hosts, but are more prevalent in individuals with IMMUNOLOGIC DEFICIENCY SYNDROMES. The organism may spread to the nervous system from focal infections in the lung, mastoid region, sinuses, inner ear, bones, eyes, gastrointestinal tract, and heart. Sinus infections may be locally invasive and enter the intracranial compartment, producing MENINGITIS, FUNGAL; cranial neuropathies; and abscesses in the frontal lobes of the brain. (From Joynt, Clinical Neurology, 1998, Ch 27, pp62-3)Fatal Outcome: Death resulting from the presence of a disease in an individual, as shown by a single case report or a limited number of patients. This should be differentiated from DEATH, the physiological cessation of life and from MORTALITY, an epidemiological or statistical concept.Staphylococcal Infections: Infections with bacteria of the genus STAPHYLOCOCCUS.