Biomedical subjects
Y S Hahn
Publications and source records attributed to Y S Hahn.
Risk factors in the outcome of children with minor head injury.
A subset of children with minor head injury is known to develop serious neurological consequences, but identifying this subset has been difficult. In adults, multiple variables such as skull fracture, Glasgow Coma Scale score, unconsciousness, and amnesia are significant factors that determine whether to admit the patient to the hospital and the patient's outcome. As an objective assessment of neurological function, however, the Glasgow Coma Scale has limited usefulness in children, particularly those under 36 months of age. We report our experience with 937 children having head injuries using a Glasgow Coma Scale modified for children (Children's Coma Scale). During the 6-year study period, 791 of the 937 children (84%) sustained minor head injuries (Glasgow Coma Scale or Children's Coma Scale score of 13, 14, or 15). The mean age of patients was 5.5 years. Males predominated over females by a 2:1 ratio. The most common cause of injury was a fall, followed by a pedestrian/motor vehicle accident. Seven hundred and thirty-nine of the 791 children were alert at the time of admission. Of these, 99 (13.4%) had lesions requiring surgery: 9 had subdural hematomas, 35 had epidural hematomas, 44 had depressed skull fractures, and 11 had other types of lesions. Two children (0.3%) with Glasgow Coma scores of 13 died after subsequent deterioration, 1 of a delayed epidural hematoma, the other of diffuse cerebral edema. Risk factors such as length of unconsciousness, presence of skull fractures, computed tomography findings, posttraumatic seizure, and Glasgow or Children's Coma scores were evaluated for their impact on the patient's outcome.(ABSTRACT TRUNCATED AT 250 WORDS)
Pediatric axis fractures: early halo immobilization, management and outcome.
Pediatric C-2 fractures have been managed with initial cranial skeletal tong traction or a period of bed rest for reduction and alignment followed by external and/or surgical stabilization. Thirteen children were managed with early halo orthosis to provide the initial reduction/alignment and to accomplish long-term stabilization. Eighty percent had fusion with the halo alone, and 20% went on to fuse after surgery. The average hospitalization for isolated C-2 injury was 10.6 days. Minor complications occurred in 46% of the patients. The literature is reviewed as to the management and outcome of pediatric axis fractures.
Hypopituitarism and chorioretinopathy in two siblings.
Two male siblings with chorioretinopathy and pituitary dysfunction (CPD) were found to have empty sellas on CT scan. Extensive ophthalmological and endocrinological investigation revealed the absence of gonadotrophins in both brothers and growth hormone deficiency in one. ACTH, TSH, and posterior pituitary function were normal. Karyotyping in one brother revealed a 46XY complement. Ophthalmological evaluation of three other siblings and both parents revealed normal vision and no evidence of retinopathy. The brothers represent two additional examples of CPD syndrome, suggesting a genetic etiology for this syndrome complex. The empty sellas present add another facet to the central nervous system disorders found in CPD syndrome.
Abdominal CSF pseudocyst. Clinical features and surgical management.
Twenty-six cases of abdominal cerebrospinal fluid (CSF) pseudocyst have been reviewed and the clinical features identified. Typical presentation includes abdominal pain and/or distention, with nausea or vomiting. Manifest shunt malfunction is not a prominent feature. Diagnosis can usually be confirmed by abdominal ultrasound and/or CT scan. No clear predisposing factors were identified, although a prior shunt infection was found in 62% of the patients. The number of previous shunt revisions ranged from 0 to 51 (average 11.2). This revision rate is significantly higher than in other groups of patients. CSF obtained at the time of surgery was infected 36% of the time. CSF appearance and laboratory value did not reliably indicate infection as a cause of the pseudocyst. Suggested surgical management consists of a contralateral ventriculoperitoneal shunt or a ventriculoatrial shunt.
Atrial diverticula in severe hydrocephalus.
Massive ventricular dilatation causes stretching and dehiscence of the fornix with formation of unilateral or bilateral pial pulsion diverticula of the inferior medial wall of the atrium. Enlargement of the pial pouch creates a dramatic subarachnoid cyst that may herniate downward through the incisura into the lateral mesencephalic, precentral cerebellar, and superior vermian cisterns where it displaces the brain stem, vermis, and fourth ventricle. Lateral ventricular diverticula may be identified and distinguished from the dilated fourth ventricle and dilated suprapineal recess, with which they are so commonly confused, when all of the following signs are apparent on computed tomography (CT): (1) marked unilateral or bilateral atrial dilatation; (2) focal dehiscence of the medial atrial wall; (3) ipsilateral shortening of the tentorial band in axial section; (4) focal defect in the tentorial band in coronal section; (5) draping of the medial atrial wall over the free margin of tentorium, with continuity of cerebrospinal fluid density around the edge of tentorium in axial and/or coronal sections; (6) bowing of the crus (or crura) of fornix; (7) separation of fornix from splenium, with visualization of the hernia ostium; (8) asymmetrical position of the choroid plexi, which attach to and define the lateral borders of the fornices; (9) contralateral displacement of the internal cerebral veins; and (10) septa separating diverticulum from third ventricle