Diagnostic method for differentiating external hydrocephalus from simple subdural hygroma

Abstract

Monitoring subdural pressure may be a valuable tool for differentiating subdural hygroma from external hydrocephalus in patients with mild head trauma. Additionally, the mFHI reflects the nature of the subdural collection more accurately than the standard frontal horn index.

Interhemispheric hygroma after decompressive craniectomy: does it predict posttraumatic hydrocephalus?

“…13,14,16 Data from subsequent CT scans were recorded as well. For the purposes of this study, posttraumatic hydrocephalus was defined as the presence on any of the control CT scans of both of the following criteria: 1) modified Frontal Horn Index score greater than 33% (the greatest width of the frontal horns divided by the bicortical distance in the same plane), 11 and 2) Gudeman CT criteria. 9 Gudeman CT criteria include the distended appearance of the anterior horns of the lateral ventricles and the enlargement of the temporal horns and third ventricle in the presence of normal or absent sulci.…”

Craniectomy-Associated Progressive Extra-Axial Collections with Treated Hydrocephalus (CAPECTH): Redefining a common complication of decompressive craniectomy

“…[26][27][28] It has been theorized that decompressive surgery and durotomy perturb homeostatic pulsative CSF dynamics and allow egress of spinal fluid into the extra-axial compartments as an external manifestation of hydrocephalus. Our data, however, do not support this concept.…”

Treatment of patients with traumatic subdural effusion and concomitant hydrocephalus

“…Ventricular size diagnosis based only on the ratio between frontal horns and inner table distance would be unreliable, especially when the subdural collection increases in size. Huh et al 5 suggested that the ventricular size should be calculated by the mFHI, which is defined as the largest width of the frontal horns divided by the bifrontal bicortical distance at the same level rather than the inner table distance. In their patient series, they tried to differentiate external hydrocephalus from simple subdural hygroma, because CSF shunting could be the treatment for the former, whereas the same procedure may exacerbate a hygroma.…”

“…Hydrocephalus is suggested when the FHI is larger than 0.5, but conventional FHI is underestimated when there is widening of the subdural space. Huh et al 5 used the mFHI in these cases and found that hydrocephalus is present when the mFHI is greater than 0.33 (Fig. 1).…”