cerebrospinal fluid 5-hydroxyindoleacetic acid

5-HT is a kind of guanamine. The 5-HT neurons are mainly concentrated in the middle nucleus of the brainstem in the brain, and the fibers are up to the cerebral cortex, striatum, blood brain and hypothalamus. Down to the glial zone, side angle and anterior horn of the gray matter. The synthesis of 5-HT is that tryptophan produces 5-hydroxytryptophan (5-HTP) under the action of tryptophan hydroxylase, and decarboxylates to form 5-HT under the catalysis of serotonin decarboxylase. Under the action of monoamine oxidase, 5-HT is degraded to 5-hy-droxyindoleacetic acid (5-HIAA). Basic Information Specialist classification: neurological examination classification: cerebrospinal fluid examination Applicable gender: whether men and women apply fasting: fasting Tips: After collecting the specimen, it should be sent immediately and placed for too long, which will affect the test results. Normal value (1) Fluorescence spectrophotometry Lumbar puncture 5-HIAA86.28±23.22ng/ml. (2) HPLC Ventricular puncture 5-HIAA33.67±12.43mg/L. Clinical significance Abnormal result Depressive psychosis, myoclonus, Down syndrome, micro-cerebral dysfunction, phenylketonuria caused by mental retardation in patients with CSF 5-HIAA content also decreased, epilepsy 5-HT and 5-HIAA content decreased; cranial Department of trauma, suppurative meningitis, subarachnoid hemorrhage and other patients with CSF, increased 5-HIAA concentration, cerebral hemorrhage and other 5-HT increased. Need to check the crowd Patients with mental disorders. Low results may be diseases: high results in children with myoclonic epilepsy may be diseases: considerations for purulent meningitis Preparation before inspection: 1. Patients with suspected intracranial pressure must have a fundus examination before examination. Requirements for inspection: 1. If the patient has symptoms such as breathing, pulse, or abnormal color when puncture, stop operation immediately and deal with it accordingly. 2. When intrathecal administration, the same amount of cerebrospinal fluid should be released first, and then the same amount of conversion liquid is injected. Inspection process Examination by ventricular puncture: (1) The anterior approach (pre-angle puncture method) puncture point is 2cm after the hairline, (the midpoint of the eyebrow center is connected to the median sagittal line to the rear 8~9CM) 2.5cm next to the midline. The needle insertion direction is parallel to the sagittal plane and points to the external auditory canal. The normal depth is 4 to 6 cm. (2) The posterior entry method (post-angular puncture method) puncture point is 6 to 7 cm on the occipital trochanter and 3 cm on the midline. The needle insertion direction is parallel to the sagittal plane and points to the midpoint of the upper edge of the ankle. The normal depth is 4.5 to 5.5 cm. (3) The side entry method (the rear part of the puncture angle or the triangle area) puncture point is 1 cm on the apex of the ear wheel, and the vertical direction is pierced 1 cm later. The normal depth is 4 to 5 cm. (4) Side crack point puncture method: the line segment with a side crack of 60° and an angle of 2.5 cm, vertical cortical puncture, depth of about 3 cm. Not suitable for the crowd 1. If there is obvious papilledema or cerebral palsy, contraindications are contraindicated. 2. Patients who are in shock, exhaustion or endangered state and local skin inflammation, and lesions in the posterior cranial fossa are contraindicated. Adverse reactions and risks If the patient has symptoms such as breathing, pulse, or abnormal color during puncture, stop the operation immediately and deal with it accordingly.