[Cephalic index in the case of chronic subdural hematomas; a preliminary report].

As a low cephalic index (cephalic index = breadth x 100/length), also called "dolichocephaly" has often been observed in patients with chronic subdural hematomas, the relation between the occurrence of chronic subdural hematoma and the cephalic index was investigated. 62 patients (male: 51, female: 11) with chronic subdural hematomas who were admitted during the past 5 years, and 62 patients (male: 51, female: 11) aged 40 years and over who visited the hospital for head injury which caused no intracranial hematoma, randomly sampled, as a control group, a total of 124 patients were studied for cephalic index on plain craniogram. The average cephalic index was 79.0 for males and 81.3 for females in the chronic subdural hematoma group, compared with 82.1 for males and 83.3 for females in the control group. The former index was lower than the latter for both sexes. Dolichocephaly was observed in 8 out of 51 males (15.7%) with chronic subdural hematomas while it was observed in only 1 out of 51 males (2.0%) in the control group. Since it has been reported that dolichocephaly depends on the development of arcus superciliaris and protuberantia occipitalis externa by the interaction between androgen and GH in males as well as time of closure of the cranial suture in childhood, and as androgen accelerates offensive behavior and GH stimulates the synthesis of collagen, the occurrence of chronic subdural hematoma is potentially related with sexual or individual variation in such endocrinic environments.(ABSTRACT TRUNCATED AT 250 WORDS)