Exploring Postoperative Cognitive Dysfunction and Delirium in Noncardiac Surgery Using MRI: A Systematic Review

Table 1

Overview of included postoperative cognitive dysfunction (POCD) studies.

Study	Design	Surgery	Patients and controls (age)	Cognitive test (timing)	MRI system	MRI timing	MRI modalities	Statistics	Major findings
Sato et al. [40]	Prospective, case-control	Breast cancer surgery	30 patients (60 ± 7); chemonaïve; postmenopausal; 20 healthy controls (59 ± 5)	Digital span back; Stroop color word test; Wechsler adult memory scale; Digit symbol coding; Digit cancellation task (1/2 days before surgery, within 1 week of surgery)	3.0T Philips	1x presurgery; 1x postsurgery	T1 weighted VBM	ANCOVA; multiple regression	Attention domain subtest lower score in patients compared to control after 1 week.; Significant group by time interaction in the right thalamus (); Correlation between change ratio of digit cancellation task and decrease of thalamus rGMV
Price et al. [37]	Prospective, case-control	Total knee arthroplasty (TKA)	31 patients (70.8 ± 7.0) Charlson comorbidity 1 + 1; 12 arthritis patient controls, age and education matched (72.2 ± 5.3) Charlson comorbidity 1.7 + 1.8	Hopkins verbal learning,; story memory,; brief visual spatial memory,; digital span back,; spatial span subset,; digit symbol substitution,; controlled oral word association,; Stroop color word test, category fluency, judgment of line orientation,; and finger tapping test; (baseline, 3 wk, 3 mo, 1 yr)	3.0T Siemens	1x presurgery	T1 weighted	Hierarchical regression models	Preoperative leukoaraiosis and lacunae volume improve the prediction model of baseline Stroop color word test of 3 wk postoperative executive function decline, but not with memory decline
Chen et al. [35]	Prospective, cross-sectionalstudy	Open abdominal surgery	39 patients; (72 ± 8); ASA 2-3; 35 controls (71 ± 5)	Wechsler adult memory scale and intelligence scale,; trail making; grooved pegboard; (1 day before and 3 days after surgery)	1.5T Siemens	1x presurgery	T1 weighted	POCD (13) versus non-POCD (23)	6% reduction of hippocampus volume in POCD group compared to non-POCD, this reduction is correlated negatively with Z score