OBJECTIVE: This study aimed to investigate the correlation between the MRI high-intensity zone (HIZ) and the pathogenesis of discogenic low back pain.
METHODS: Literature from PubMed, EMBASE, Cochrane Library, Science Direct, China Knowledge Network, Wanfang Database, and China Biomedical Literature Database was searched until August 2023. Cohort studies including patients with low back pain who underwent lumbar spine MRI and discography, as well as the results evaluating the correlation between HIZ and discography for morphological changes in the disc and pain replication phenomena, were included in the analysis. The literature that met the inclusion criteria was screened, and the methodological quality of the included studies was evaluated. Meta-analysis of the extracted data was performed by using RevMan 5.1.1.
RESULTS: In total, 28 reports were included in this meta-analysis. There was a statistically significant correlation between a positive HIZ and abnormal disc morphology in discography (OR 28.15, 95% CI [7.38, 107.46], p < 0.00001). Patients with HIZ-positive discs had a significantly higher incidence of consistent pain (71.0%, 969/1365) than those with HIZ-negative imaging (29.0%, 1314/4524) (OR 7.71, 95% CI [5.29, 11.23], p < 0.00001).Segments that were HIZ-positive and had abnormal disc morphology had a higher incidence of consistent pain (86.1%, 230/267) than HIZ-negative subjects (32.2%, 75/233) (OR 14.09, 95% CI [2.12, 93.48], p = 0.006).
CONCLUSIONS: A positive MRI T2-weighted image of the lumbar disc with HIZ indicates disc degeneration. In addition, HIZ may be a specific indicator for the physical diagnosis of discogenic low back pain. A more advanced degree of disc degeneration on the basis of HIZ positivity corresponded to a greater probability of discography-induced consistent pain, whereas the degree of disc degeneration on the basis of HIZ negativity was less correlated with contrast-induced consistent pain.

UNASSIGNED: Early studies suggested that the high-intensity zone (HIZ) on lumbar MRI was a diagnostic sign of painful internal disc disruption (IDD). However, recent studies have questioned its diagnostic value. This study is conducted to explore imaging features of HIZ and to investigate the correlation between these characteristics and low back pain (LBP), further studying the predictive value of HIZ.
UNASSIGNED: A retrospective study of 1188 cases was performed. MR images were read and analyzed by two experienced, blinded radiologists.
UNASSIGNED: A total of 575 (48.4%) individuals exhibited HIZ. The prevalence of posterior HIZ (32.3%) was significantly higher than that of anterior HIZ (23.6%; P < 0.01). Round type was the most common shape (61.0%) on sagittal view. Only 37 HIZs (4.6%) were identified on axial views. A total of 263 HIZ discs (32.5%) were found to have additional diagnostic signs of IDD, which is difficult to distinguish from the annulus fibrosus. In subjects with consecutive slides showing HIZ, the incidence of LBP was significantly higher than in single-slide HIZ individuals (58.0% vs 48.6%, P < 0.05).
UNASSIGNED: MRI-visualized HIZ is a highly valuable method of screening for lumbar IDD. It is demonstrated that consecutive-slide HIZ was a more reliable indicator for discogenic LBP than single-slide HIZ.

OBJECTIVE: Previous literatures have demonstrated widely variable clinical results after transsacral epiduroscopic laser decompression (SELD) and the factors predicting outcomes are not yet established. Therefore, we analyzed the clinical outcome and associated predictive factors of SELD in patients with lumbar disc herniation.
METHODS: Between 2015 and 2018, 82 patients who underwent single-level SELD and followed up at least 6 months were enrolled. The overall success rate (excellent or good results at final follow-up) was 58.5% according to Odom\'s criteria. Based on this result, patients were divided to 2 groups: a favorable group (n = 48) and an unfavorable group (n = 34). A retrospective review of the baseline characteristics and clinical outcome were conducted to reveal the predictive factors.
RESULTS: As expected, improvement of pain and patient satisfaction, was more favorable in the favorable group (p < 0.05). Moreover, the rate of additional procedure was lower in the favorable group (4.2%, 2 of 48 patients) than in the unfavorable group (35.3%, 12 of 34 patients) (p = 0.011). Among the various baseline characteristics, the only significant predictive factor for favorable outcome was the presence of a high-intensity zone (HIZ) on preoperative magnetic resonance imaging (50.0% [24 of 48 patients] in the favorable group vs. 11.8% [4 of 34 patients] in the unfavorable group; odds ratio, 15.67; p = 0.024).
CONCLUSIONS: Although SELD for lumbar disc herniation resulted in a less favorable clinical outcome than that reported in previous studies, in patients with a HIZ, SELD can be an effective minimally invasive surgery to relieve low back pain and/or leg pain.

To explore the features of high-intensity zone (HIZ) in anterior annulus fibrosus and assess the association of anterior HIZ with low back pain (LBP).
A retrospective study of 5,940 discs in 1,188 individuals was conducted.
Subjects\' information and LBP symptoms confirmed by an orthopedic surgeon were acquired from the medical record. Magnetic resonance (MR) image reading and analysis were performed by two experienced blinded radiologists.
Two hundred eighty individuals exhibited 355 anterior HIZs in 355 discs. The prevalence was 23.57%; 88.45% were located in the inferior part of the annulus fibrosus. It frequently occurred in the middle and upper segments of lumbar spine, especially at L3/4 (45.63%). Of the 355 anterior HIZs, only 79 (22.25%) were consecutive-slides HIZ. Round type (63.38%) was the most common shape of anterior HIZs. The highest prevalence was found in individuals aged 60-69 years. LBP was confirmed in 141 anterior-HIZ individuals. The incidence of LBP in anterior-HIZ individuals was significantly higher than in non-HIZ subjects (50.36% vs 35.24%, χ2 = 18.314, P < 0.001).
Anterior HIZ is a lower-prevalence, age-related sign on lumbar MR images. The spatial distribution of anterior HIZ can be distinguished from posterior HIZ. The number of consecutive anterior HIZ slides might suggest fewer Dallas grade 4 anterior annular disruptions in this sample. Anterior HIZ was correlated with LBP.

Background: Transsacral epiduroscopic laser decompression (SELD) is a very noninvasive surgery, so it is effective for elderly patients and athletes and is a new and minimally invasive therapeutic technique that may be useful in many patients with discogenic low-back pain (LBP) having high signal intensity zone (HIZ) in magnetic resonance imaging (MRI). We investigated the clinical outcomes of SELD in Japanese patients with discogenic LBP having HIZ as a first trial. Methods: The subjects consisted of 52 patients who underwent SELD and were followed up for at least 6 months. All patients with LBP with HIZ were operative using the SELD technique. Outcomes of the patients were assessed with visual analogue scale (VAS) for LBP, the Oswestry disability index (ODI), and the EuroQol 5 dimension (EQ-5D). Statistical analyses were carried out using a paired t-test. A p-value of <0.05 was considered significant. For statistical analysis, we used the SPSS software program. Results: At 12 months after the procedure, the average VAS score for LBP fell to 1.2 from 5.6 (p-value <0.05). The ODI score also dropped from the preoperative level of 22.3 to 8.8. The EQ-5D score also significantly increased from the preoperative level of 0.865 (SD 0.10) to 0.950 (SD 0.05). Eight cases of intraoperative cervical pain were observed as complications with no cases of hematomas, infections, and postoperative neurosis was observed. Conclusions: SELD provides a novel minimally invasive technique capable of performing multilevel intervertebral surgery. We believe that SELD is an effective method of treating discogenic LBP due to HIZs.

UNASSIGNED: A high-intensity zone (HIZ) in an intervertebral disc of the lumbar spine is a high-intensity signal located in the posterior annulus fibrosus on T2-weighted magnetic resonance imaging (MRI). There is limited information on the prevalence of HIZ in the lumbar spine according to age. The aim of this cross-sectional study was to investigate the prevalence of HIZ in the lumbar spine by age and the correlation between HIZ and other degenerative findings, such as disc degeneration, disc bulging and herniation, and changes in adjacent vertebral endplates on lumbar MRI.
UNASSIGNED: We retrospectively reviewed MRI studies of 305 patients (1525 discs) with low back pain, leg pain, or numbness. The prevalence of HIZ was calculated in 5 age groups (<20, 20-39, 40-59, 60-79, 80-91 years).
UNASSIGNED: The number of patients in the 5 age groups was 19, 38, 69, 145, and 36, respectively. The prevalence of HIZ in the 5 age groups was 11.8%, 47.3%, 52.2%, 42.8%, and 50.0%, respectively. Disc degeneration was observed in 58.1% and 39.2% of discs with and without HIZ, respectively; disc bulging and herniation was observed in 63.9% and 41.1% and intensity changes at adjacent end plates in 11.6% and 10.0%, respectively.
UNASSIGNED: Prevalence of HIZ from the third decade of life onward was around 50%, with no significant change in prevalence beyond the age of 20 years. HIZ was correlated with disc degeneration, disc bulging, and disc herniation in patients with LBP, leg pain, or numbness.

BACKGROUND: It is well known that internal disc disruption (IDD) is accelerated by factors such as aging and injury. High- intensity zone (HIZ) on lumbar MRI is usually considered a marker of painful IDD. However, many painful IDD show no HIZ. This suggests that the risk factors of HIZ may be different to these of IDD. The purpose was to clarify the correlation between the HIZ on lumbar MR and the factors, including gender, age, body weight, and low back pain (LBP).
METHODS: Characteristics were obtained from the medical record. The MR images, biplanar post-discography radiographs, and post-discography CT images were reviewed and rated by two experienced radiologists in a blinded fashion.
RESULTS: Annular HIZ correlated significantly with age (OR = 1.011), body weight (OR = 1.022), and LBP symptom (OR = 1.527). The lowest two HIZ prevalence rates were in the second and the third decades (11.54% and 7.84%). The highest prevalence was in the sixth decade (38.03%). The body weight was positively associated with the HIZ prevalence. There was a significant difference in HIZ prevalence between symptomatic and asymptomatic patients (36.16% vs. 26.96%, P < 0.05). All the HIZ discs exhibited grade 3 or grade 4 disruptions, but only 9 discs (9/16, 8 exhibited grade 4 annular tears) were detected with exact pain reproduction.
CONCLUSIONS: It is demonstrated that the presence of HIZ on lumbar MR image was associated with aging, high body weight, and low back pain symptom. HIZ sign indicated a part of the natural history of disc degeneration but was not an actual source of low back pain.

UNASSIGNED: Magnetic resonance imaging (MRI) of the lumbar spine is commonly used to identify the source of low back pain (LBP); however, its use has been questionable. Throughout the years, numerous lumbar phenotypes (e.g., endplate abnormalities, Modic changes, black disc) have been studied as possible pain generators. High-intensity zones (HIZs) are of particular interest as they may represent annular tears. However, for over three decades, there has been heated debate as to whether these imaging biomarkers are synonymous with LBP. Therefore, the following study addressed a systematic review of the reported literature addressing the relationship of HIZs and LBP.
UNASSIGNED: A systematic review was conducted via MEDLINE, SCOPUS, Cochrane, PubMed, PubMed Central, EMBASE via Ovid, and Web of Science with the following search terms: \"HIZ,\" \"high intensity zone,\" or \"high intensity zones\" and \"low back pain,\" \"pain,\" \"lumbago,\" and/or \"sciatica.\" Specific exclusion criteria were also maintained. Two independent reviewers searched the literature, selected the studies, and extracted the data.
UNASSIGNED: We identified six studies from our search strategy that met the inclusion criteria from a total of 756 possible studies. One cross-sectional population-based study and five comparison studies were identified, which provided information regarding the prevalence of HIZs. The prevalence of HIZs was 3 to 61% in subjects with LBP and 2 to 3% in subjects without LBP. Only three studies suggested a significant association between the presence of HIZ and LBP with or without sciatica.
UNASSIGNED: Our systematic review has found evidence that HIZs may be a possible risk factor for LBP; however, a mismatch of the clinical relevance of HIZs between studies still remains. The available evidence is limited by small sample size, heterogeneous study populations, and lack of standardized imaging methods for phenotyping. HIZs may be important lumbar biomarkers that demand further investigation and should be considered in the global imaging assessment of the spine, which may have immense clinical utility. Further large-scale studies with standardized imaging and classification techniques as well as the assessment of patterns of HIZs are necessary to better understand their role with LBP development.

OBJECTIVE: To examine the impact of demographic, clinical, and genetic factors as well as herniated discs on 5-year development of disc degeneration in the lumbar spine, and to investigate associations between changes in lumbar degenerative findings and pain.
METHODS: In 144 patients with lumbar radicular pain or low back pain, we scored disc degeneration, herniated discs, and high-intensity zones in the posterior annulus fibrosus on lumbar magnetic resonance imaging (MRI) at baseline and 5-year follow-up. Genotyping (TaqMan assay) was performed for genes encoding vitamin D receptor (VDR), collagen XIα (COL11A), matrix metalloproteinase 1/9 (MMP1/MMP9), and interleukin 1α/1RN (IL-1α/IL-1RN). Associations were analyzed using multivariate linear regression adjusted for age, sex, smoking, body mass index, and baseline scores for degenerated discs and herniated discs (when analyzing impact of baseline factors) or for pain (when analyzing associations with pain).
RESULTS: Progression of disc degeneration over 5 years was significantly (p < 0.001) related to higher age and less disc degeneration at baseline, but not to sex, smoking, body mass index, herniated discs, or variants in the studied genes. No associations were identified between changes in disc degeneration or high-intensity zones and pain at 5-year follow-up. However, increased number of herniated discs over 5 years was associated with pain at rest (p = 0.019).
CONCLUSIONS: Age and disc degeneration at baseline, rather than genetic factors, influenced the 5-year development of disc degeneration in patients with lumbar radicular pain or low back pain. Development of herniated discs was related to pain at rest.

BACKGROUND: This meta-analysis aimed to assess the correlation between the high-intensity zone (HIZ) of a lumbar MRI and discography.
METHODS: We conducted an electronic search of the PubMed, MEDLINE, Embase, and ScienceDirect databases from their respective inceptions to October 2016 using the following search terms: \"low back pain,\" \"discogenic low back pain,\" \"HIZ or high-intensity zone,\" and \"discography\". Relevant journals and conference proceedings were manually searched. Two reviewers independently assessed the quality of the studies, extracted data from the included studies, and analyzed the data.
RESULTS: Eleven studies were included. The results of the meta-analysis indicated that outstanding relativity and statistically significant correlations were observed between the HIZ and abnormal disc morphology (OR = 47.79; 95% CI: 17.07 to 133.77; P < 0.00001), HIZ and pain reproduction (OR = 8.65, 95% CI: 6.01 to 15.23, P < 0.00001), and HIZ and abnormal morphology pain reproduction (OR = 11.74, 95% CI: 1.99 to 69.36, P = 0.007).
CONCLUSIONS: The presence of an HIZ on a lumbar MRI T2-weighted image indicates abnormal disc morphology. There is a strong relationship between the HIZ and pain reproduction. The HIZ can be an effective index for prediction of discogenic low back pain.