Is medial temporal injury responsible for pediatric postconcussion syndrome? A prospective controlled study with single-photon emission computerized tomography

Abstract

INOR TBI has been the subject of intense investigation in recent years because it has been increasingly realized that, despite an apparently normal head CT scan, there may be subtle organic brain damage, which may be associated with distressing neuropsychological sequelae. 23 Postconcussion syndrome-including symptoms such as headache, irritability, poor concentration, memory disturbances, dizziness, anxiety, and depression-has been reported to occur in up to 80% of the patients following minor TBI. 8,18 Persistent postconcussion syndrome, defined as persistence of symptoms of postconcussion syndrome beyond 3 months, is seen in more than 30% of patients, and up to 15% may have persistent, disabling symptoms beyond 6 months. 2,4 Because of the lack of more sensitive investigative tools these symptoms were considered to be psychological rather than organic in nature. Many treating physicians today tend to take a suspicious view of postconcussion symptoms because there are compensation issues involved in many cases. Unfortunately, children who are not seeking compensation are also treated similarly with "reassurance" or are subjected to a battery of neuropsychological tests with mixed results.Recent research, however, is pointing toward an organic cause for these postconcussion symptoms. Nedd, et al., 16 compared SPECT and CT scanning results in 16 patients with mild-to-moderate TBI; SPECT scans revealed structural lesions in 87.5% compared with 37.5% seen on the CT scans. In another study Varney, et al., 22 reported on 14 patients with minor TBI and PPCS in whom the results of CT scanning were normal; however, SPECT scanning consistently revealed MTH. We have also previously documented MTH in patients with postconcussion vertigo 1 and therefore decided to target the medial temporal lobe in this study.Both SPECT and PET scanning are dynamic imaging modalities that can be used to measure regional blood flow and cerebral blood volume; both have proven to be much more sensitive than CT or MR imaging, with sensi- J. Neurosurg: Pediatrics / Volume 102 / March, 2005Object. The authors sought to correlate the finding of medial temporal hypoperfusion (MTH) demonstrated on single photon emission computerized tomography (SPECT) with pediatric persistent postconcussion syndrome (PPCS) and to ascertain its usefulness in routine clinical practice.Methods. Thirty consecutive children with minor head injury and features of PPCS underwent SPECT scanning within 72 hours of injury. Those children having MTH on SPECT were included in the test group (14 patients), and the remaining 16 children comprised the control group. At the end of a 3-month period SPECT scanning was repeated and the incidence of PPCS was assessed clinically in both groups.Repeated SPECT scanning at 3 months revealed persisting MTH in 13 children (93%) in the test group; no child developed MTH in the control group. Twelve children were found to have PPCS in the MTH group compared with only two in the control group, and this was highly statistically significant (rel...

Contributions of neuroimaging, balance testing, electrophysiology and blood markers to the assessment of sport-related concussion

“…Essentially, SPECT measures regional cerebral blood flow. Some preliminary work in adults with MTBI identified SPECT abnormalities in the medial temporal lobe,25 and a small study on children (ages 2–18) with MTBI suggested that medial temporal hypoperfusion on SPECT was associated with persistent post-concussion syndrome 26. This latter study with children had many scientific limitations, including the lack of clinical data, small numbers, and no neuropsychological assessment.…”

Clinical Utility of SPECT Neuroimaging in the Diagnosis and Treatment of Traumatic Brain Injury: A Systematic Review

“…A total of 19 longitudinal analyses met all inclusion criteria for the main analysis and included five intervention studies (Table 1; [41]; [46]–[53]). A total of 903 persons were assessed in these studies with NOS scores between 4 to 8.…”

Concussion in the Pediatric and Adolescent Population: “Different Population, Different Concerns”

“…It may be appropriate to consider MRI in patients with persistent symptoms, although a well‐accepted guideline as to the exact duration of symptoms that warrant such imaging has not yet been defined for the pediatric population. Other nontraditional imaging studies, such as functional MRI and single‐photon emission CT, may prove to have a role in the prediction of concussion severity and time to clinical recovery [28,66].…”