MINORMINOR HEAD INJURY & HEAD INJURY & MEDIAL TEMPORAL MEDIAL TEMPORAL

DAMAGEDAMAGE A PROSPECTIVE CONTROLLED A PROSPECTIVE CONTROLLED

STUDY USING SPECTSTUDY USING SPECT

Deepak Agrawal, Naveen K*Departments of Neurosurgery and *Nuclear medicine, All India Institute of

Medical Sciences, New Delhi

BACKGROUNDBACKGROUND

EXPERIMENTAL EVIDENCEEXPERIMENTAL EVIDENCEBilateral dentate hilar neuron loss Bilateral dentate hilar neuron loss

is a consistent finding two weeks is a consistent finding two weeks after minor head injury and is after minor head injury and is uniformly associated with memory uniformly associated with memory dysfunctiondysfunction

Smith DH, Lowenstein DH, Gennarelli DI, McIntosh TK. Persistent memory dysfunction is associated with bilateral hippocampal damage following experimental brain injury. Neurosci Lett 1994;168:151-154

WHY MEDIAL TEMPORAL LOBE?

•Hippocampus is especially vulnerable to insults such as ischemia, hypoxia, and seizures

•Extent of hippocampal damage may be correlated with severity of memory impairment

Rempel-Clower NL, Zola SM, Squire LR, Amaral DG. Three cases of enduring memory impairment after bilateral damage limited to the hippocampal formation. J Neurosci 1996;16:5233-5255.

AIMS & OBJECTIVESAIMS & OBJECTIVESDocument medial temporal Document medial temporal

hypoperfusion (MTH) on SPECT in hypoperfusion (MTH) on SPECT in children with minor head injurychildren with minor head injury

To evaluate MTH on SPECT as a risk To evaluate MTH on SPECT as a risk factor for development of factor for development of persistent persistent postconcussion syndrome (PPCS) at postconcussion syndrome (PPCS) at three months three months

MATERIALS AND METHODSMATERIALS AND METHODS

PROSPECTIVE STUDYPROSPECTIVE STUDY

PERIOD- Nov 2001 TO Oct 2002 PERIOD- Nov 2001 TO Oct 2002

MINOR HEAD INJURYMINOR HEAD INJURY Loss of consciousness <30 Loss of consciousness <30

minutes.minutes. GCS score 13 to 15.GCS score 13 to 15. Posttraumatic amnesia <24 hours.Posttraumatic amnesia <24 hours.

[criteria published by the members of the Mild Traumatic brain injury Interdisciplinary Special Interest Group (BISIG)]

Kay T, Harrington DE, et al. Definition of mild traumatic brain injury. J Head Trauma Rehabil 1993;8:86

The Post The Post Concussion Concussion Syndrome Syndrome Checklist score Checklist score ((PCSCPCSC)- via )- via discussion with discussion with parent & childparent & child

Gouvier WD, Cubic B, Jones G, Brantly P, Cutlip Q. Postconcussion symptoms and daily stress in normal and head-injured college populations. Arch Clin Neuropsychol 1992;7:193-211.

30 children

MTH Group (14) Non MTH group (16)

PCSC administeredWithin 72 hrs& At 3 months

PCSC administeredWithin 72 hrs& At 3 months

POSTCONCUSSION SYNDROMEPOSTCONCUSSION SYNDROME

NCCT headNCCT head

INVESTIGATIONINVESTIGATION

Clinical (Clinical (PCSCPCSC))

SPECT scan brainSPECT scan brain

(Within 72 hours & at 3 mths of (Within 72 hours & at 3 mths of injuryinjury ) )

30 Children with minor head injury

SPECT scan & PCSC administration(within 72 hrs)

Medial temporal hypoperfusion(14 children)

No Medial temporal hypoperfusion(16 children)

3 months laterRepeat SPECT & clinical evaluation

(PCSC)

3 months laterRepeat SPECT & clinical evaluation

(PCSC)

STUDY DESIGNSTUDY DESIGN

SPECT scanning was done using SPECT scanning was done using 99Tcm-ECD on a dual headed GE 99Tcm-ECD on a dual headed GE 'Varicam' scanner.'Varicam' scanner.

The final data was displayed on a 10 The final data was displayed on a 10 grade color scale and semi grade color scale and semi quantitative analysis performed. quantitative analysis performed.

SPECTSPECT

Regional cerebral perfusion <10% of Regional cerebral perfusion <10% of contralateral lobe, or in case of bilateral contralateral lobe, or in case of bilateral involvement, less than 20% of cerebelluminvolvement, less than 20% of cerebellum

ABNORMAL SPECT ABNORMAL SPECT SCANSCAN

RESULTS

12 children were found to have cognitive dysfunction in the MTH group compared to only two in the control group

Relative risk (95% CI)= 6.86(1.84-25.51). P=0.0003

MTH group Control group

RESULTS

RESULTS

ADVANTAGES OF SPECTADVANTAGES OF SPECTCertain skills are age dependent-Certain skills are age dependent-

Injury in the preschool years Injury in the preschool years seems to affect the process of seems to affect the process of learning to read.learning to read.

•SPECT may help in identification SPECT may help in identification and prognostication in this and prognostication in this subgroup of childrensubgroup of children

CONCLUSIONSCONCLUSIONS

Children with Children with medial temporal medial temporal hypoperfusionhypoperfusion are much more are much more likely to develop memory & likely to develop memory & learning disorderslearning disorders

CONCLUSIONSCONCLUSIONSOurs is the first study of its kind Ours is the first study of its kind

correlating correlating medial temporal medial temporal hypoperfusionhypoperfusion on SPECT with on SPECT with persistent cognitive dysfunction in persistent cognitive dysfunction in childrenchildren

SPECT-platform for testing the efficacy SPECT-platform for testing the efficacy of various neurobehavioural and of various neurobehavioural and pharmacological interventions.pharmacological interventions.

THANK THANK YOUYOU