IS ROUTINE COMPUTED TOMOGRAPHIC (CT) SCANNING NECESSARY IN SUSPECTED BASAL SKULL FRACTURES

The aim of this prospective observational study was to assess the yiel d of routine fine-cut computed tomographic (CT) scans in patients with suspected basal skull injuries. Over an 8 month period in 1994, 500 c onsecutive head-injured patients were examined for clinical signs of b asal skull fracture and underwent fine-cut (5 mm) CT scans through the skull base in addition to standard (10 mm) cuts through the vault. Cl inical signs were present in 144 patients (144/500, 28.8 per cent) of which 75 (75/144, 52 per cent) had corresponding CT evidence of fractu re. A further 22 patients (22/500, 4.4 per cent) had no clinical signs but fractures were seen on CT. The presence of cranial nerve injury, cerebrospinal fluid leak, epistaxis, periorbital bruising, and two or more signs, were more likely to be associated with positive CT scans ( P<0.001, chi(2) tests). The incidence of associated mass lesions was 5 0.5 per cent, of which 55.1 per cent required craniotomy. This was sig nificantly higher than in patients without evidence of skull base frac ture (16.6 per cent) (P<0.001, chi(2) 27.165). Six patients, two of wh om had meningitis, required surgical repair of the dural defects seen on CT. The diagnostic yield of routine fine-cut CT scans in this sub-t ype of head injury is 52 per cent, and is of value in detecting associ ated mass lesions or significant dural defects which may require surgi cal intervention. (C) 1997 Elsevier Science Ltd.