The outcome predicted value of enhanced MRI for prolapsed or sequestrated lumbar disc herniation / 中华骨科杂志

ABSTRACT

Objective:To analyze the predictive value of enhanced MRI in the outcome of prolapsed and sequestrated lumbar disc herniation through a retrospective analysis.Methods:A retrospective analysis of the data of 64 patients with prolapsed and sequestrated lumbar disc herniation from January 2015 to December 2018, including 38 males and 26 females; age 35.72±12.44 years (range, 22-64 years) ; 43 cases of prolapsed type, 21 cases of sequestrated type. Conservative treatment was the first choice for all patients, in case of surgical indications during the treatment, percutaneous endoscopic lumbar discectomy or fenestration discectomy will be performed. Enhanced MRI was performed at the first and last inspections, the volume of the protrusion, the thickness of rim enhancement (Tr), and the extent of rim enhancement (Er) were measured and calculated at the same time. According to the ring around the protrusion, the size of the rim-enhancement area was divided into type I-III; then compared the relationship between the rim-enhancement signal differentiation and the resorption rate of protrusions, and the correlation between Tr, Er values and the resorption rate of protrusions during the initial inspection.Results:Among the 64 patients, 42 patients completed conservative treatment, and 22 received surgical treatment. According to the rim-enhancement signal differentiation, 23 cases were treated conservatively for type I, 3 cases were treated by surgery; 16 cases were treated for type II conservatively, 7 cases were treated by surgery; 3 cases were treated for type III conservatively, and 12 cases were treated by surgery. All patients were followed up for 12 to 34 months. Among 42 conservatively treated patients, The volume of the protrusion before treatment was 2 645.67±690.86 mm 3, and the volume of the protrusion after treatment was 842.76±573.35 mm 3. The volume of protrusions before and after treatment was statistical significance ( t=11.897, P<0.001), Tr was 1.38±0.83 mm, and Er was 73.08%±34.39%, the resorption rate of protrusions was 65.10%±24.50%, and 39 cases (92.86%, 39/42) reached the standard for protrusion resorption (resorption rate ≥30%); 23 cases of type I , the resorption rate was 76.54%±18.62%; 16 cases of type II had an resorption rate of 56.81%±21.44%; 3 cases of type III had an resorption rate of 21.58%±12.19%. The resorption rate of type III were compared by single factor analysis of variance, and the difference was statistically significant ( F=12.885, P<0.001); 32 cases of both type I and II (82.05%, 32/39) had significant resorption (resorption rate ≥50%), and no case of type Ⅲ had significant resorption, comparing with type I and II, the difference was statistically significant ( P=0.010); Tr was positively correlated with resorption rate ( r=0.569, P<0.001), Er was positively correlated with resorption rate ( r=0.677, P<0.001). Conclusion:Under close clinical observation, parts of the prolapsed or sequestrated lumbar disc herniations can be conservatively treated, and the herniated disc can be resorption in many people and the clinical symptoms were alleviated. Rim-enhancement signal differentiation by enhanced MR has a better predictive value for the outcome of the herniation, type I is more prone to resorption, preferred conservative treatment, type Ⅲ is not easy to resorption, preferred surgery treatment, and the higher thickness of rim enhancement, the greater extend the rim-enhancement, the more prone to resorption phenomenon.