[Objective] : To explore the clinical characteristics and methods for syndrome differentiation prediction, as well as to construct a predictive model for Qi deficiency and blood stasis syndrome in patients with acute ischemic stroke (AIS). [Methods] : This study employed a retrospective case-control design to analyze patients with AIS who received inpatient treatment at the Neurology Department of The First Hospital of Hunan University of Chinese Medicine from January 1, 2013 to December 31, 2022. AIS patients meeting the diagnostic criteria for Qi deficiency and blood stasis syndrome were stratified into case group, while those without Qi deficiency and blood stasis syndrome were stratified into control group. The demographic characteristics (age and gender), clinical parameters [time from onset to admission, National Institutes of Health Stroke Scale (NIHSS) score, and blood pressure], past medical history, traditional Chinese medicine (TCM) diagnostic characteristics (tongue and pulse), neurological symptoms and signs, imaging findings [magnetic resonance imaging-diffusion weighted imaging (MRI-DWI)], and biochemical indicators of the two groups were collected and compared. The indicators with statistical difference (P < 0.05) in univariate analysis were included in multivariate logistic regression analysis to evaluate their predictive value for the diagnosis of Qi deficiency and blood stasis syndrome, and the predictive model was constructed by receiver operating characteristic (ROC) curve analysis. [Results] : The study included 1 035 AIS patients, with 404 cases in case group and 631 cases in control group. Compared with control group, patients in case group were significantly older, had extended onset-to-admission time, lower diastolic blood pressure, and lower NIHSS scores (P < 0.05). Case group showed lower incidence of hypertension history (P < 0.05). Regarding tongue and pulse characteristics, pale and dark tongue colors, white tongue coating, fine pulse, astringent pulse, and sinking pulse were more common in case group. Imaging examinations demonstrated higher proportions of centrum semiovale infarction, cerebral atrophy, and vertebral artery stenosis in case group (P < 0.05). Among biochemical indicators, case group showed higher proportions of elevated fasting blood glucose and glycated hemoglobin (HbA1c), while lower proportions of elevated white blood cell count, reduced hemoglobin, and reduced high-density lipoprotein cholesterol (HDL-C) (P < 0.05). Multivariate logistic regression analysis identified significant predictors for Qi deficiency and blood stasis syndrome including: fine pulse [odds ratio (OR) = 4.38], astringent pulse (OR = 3.67), superficial sensory abnormalities (OR = 1.86), centrum semiovale infarction (OR = 1.57), cerebral atrophy (OR = 1.55), vertebral artery stenosis (OR = 1.62), and elevated HbA1c (OR = 3.52). The ROC curve analysis of the comprehensive prediction model yielded an area under the curve (AUC) of 0.878 [95% confidence interval (CI) = 0.855 – 0.900]. [Conclusion] This study finds out that Qi deficiency and blood stasis syndrome represents one of the primary types of AIS. Fine pulse, astringent pulse, superficial sensory abnormalities, centrum semiovale infarction, cerebral atrophy, vertebral artery stenosis, elevated blood glucose, elevated HbA1c, pale and dark tongue colors, and white tongue coating are key objective diagnostic indicators for the syndrome differentiation of AIS with Qi deficiency and blood stasis syndrome. Based on these indicators, a syndrome differentiation prediction model has been developed, offering a more objective basis for clinical diagnosis, and help to rapidly identify this syndrome in clinical practice and reduce misdiagnosis and missed diagnosis.

For middle-aged and elderly patients with conditions such as spinal fractures and degenerative spinal diseases, spinal internal fixation is a core surgical procedure for reconstructing spinal stability, heavily relying on the biomechanical stability provided by pedicle screw systems. Whereas, these patients are often complicated by osteoporosis that can significantly compromise the stability of the bone-pedicle screw interface, leading to a marked increase in pedicle screw loosening and surgical failure rates. The bone cement-augmented pedicle screw technique, which involves injecting bone cement into the vertebral body or screw trajectory to optimize the mechanical properties of the bone-pedicle screw composite, has been proven to significantly enhance fixation strength and effectively prevent screw-related failures, thereby reducing the incidence of internal fixation failure in high-risk populations undergoing spinal fusion. However, the widespread clinical application of this technique has faced challenges such as inaccurate clinical decision-making (indication and contraindication selection), non-standardized operative practices, and insufficient awareness of complication prevention, resulting in considerable variability in clinical outcomes and even severe complications. To address this, Prof. Luo Fei from First Affiliated Hospital of Army Medical University initiated the project and the Chinese Association Orthopaedic Surgeons organized relevant experts to develop the Evidence-based clinical practice guideline for bone cement-augmented pedicle screw technique ( version 2025), based on current evidence. The guidelines put forward 8 recommendations regarding the clinical value, scope of application, and operational standards of the technique, aiming to provide evidence-based medical support and technical standardization for clinical decision-making.

Objective·To observe the impact of hip synovitis on the long-term outcomes of free vascularized fibular grafting(FVFG)for osteonecrosis of femoral head(ONFH).Methods·Between October 2001 and December 2013,370 patients diagnosed with ONFH(556 hips)underwent FVFG.Preoperative synovitis was assessed using magnetic resonance imaging(MRI)and quantified with the Hip Inflammation MRI Scoring System(HIMRISS).Patients were divided into no synovitis group,moderate synovitis group,and severe synovitis group.Harris hip scores and the incidence of total hip arthroplasty were collected with an average follow-up duration of 90.5 months(range:5-215 months).Hip survival failure(defined as a Harris hip score lower than 80 at the final follow-up or the occurrence of total hip arthroplasty)was calculated.Multivariable Cox regression analysis was adopted to compare the influence of different degrees of synovial inflammation on long-term prognosis.Results·The proportion of hip survival failure was 28.0％in patients without synovitis and 28.5％in those with moderate synovitis,whereas it was significantly higher(60.4％)in patients with severe synovitis.The results of multivariable Cox regression analysis showed that severe synovitis was an independent risk factor for poor prognosis(HR 2.06,95％CI 1.21-3.53)after adjusting for age,gender,education level,marital status,ONFH type,affected side of ONFH,smoking history,baseline Harris hip score and other hip MRI-based covariates(collapse,bone marrow edema,and degeneration).Conclusion·Severe synovitis in patients with ONFH significantly increases the failure rate of hip preservation after FVFG,and the severity of synovitis should be considered in surgical decision-making.

Objective·To observe the impact of hip synovitis on the long-term outcomes of free vascularized fibular grafting(FVFG)for osteonecrosis of femoral head(ONFH).Methods·Between October 2001 and December 2013,370 patients diagnosed with ONFH(556 hips)underwent FVFG.Preoperative synovitis was assessed using magnetic resonance imaging(MRI)and quantified with the Hip Inflammation MRI Scoring System(HIMRISS).Patients were divided into no synovitis group,moderate synovitis group,and severe synovitis group.Harris hip scores and the incidence of total hip arthroplasty were collected with an average follow-up duration of 90.5 months(range:5-215 months).Hip survival failure(defined as a Harris hip score lower than 80 at the final follow-up or the occurrence of total hip arthroplasty)was calculated.Multivariable Cox regression analysis was adopted to compare the influence of different degrees of synovial inflammation on long-term prognosis.Results·The proportion of hip survival failure was 28.0％in patients without synovitis and 28.5％in those with moderate synovitis,whereas it was significantly higher(60.4％)in patients with severe synovitis.The results of multivariable Cox regression analysis showed that severe synovitis was an independent risk factor for poor prognosis(HR 2.06,95％CI 1.21-3.53)after adjusting for age,gender,education level,marital status,ONFH type,affected side of ONFH,smoking history,baseline Harris hip score and other hip MRI-based covariates(collapse,bone marrow edema,and degeneration).Conclusion·Severe synovitis in patients with ONFH significantly increases the failure rate of hip preservation after FVFG,and the severity of synovitis should be considered in surgical decision-making.

For middle-aged and elderly patients with conditions such as spinal fractures and degenerative spinal diseases, spinal internal fixation is a core surgical procedure for reconstructing spinal stability, heavily relying on the biomechanical stability provided by pedicle screw systems. Whereas, these patients are often complicated by osteoporosis that can significantly compromise the stability of the bone-pedicle screw interface, leading to a marked increase in pedicle screw loosening and surgical failure rates. The bone cement-augmented pedicle screw technique, which involves injecting bone cement into the vertebral body or screw trajectory to optimize the mechanical properties of the bone-pedicle screw composite, has been proven to significantly enhance fixation strength and effectively prevent screw-related failures, thereby reducing the incidence of internal fixation failure in high-risk populations undergoing spinal fusion. However, the widespread clinical application of this technique has faced challenges such as inaccurate clinical decision-making (indication and contraindication selection), non-standardized operative practices, and insufficient awareness of complication prevention, resulting in considerable variability in clinical outcomes and even severe complications. To address this, Prof. Luo Fei from First Affiliated Hospital of Army Medical University initiated the project and the Chinese Association Orthopaedic Surgeons organized relevant experts to develop the Evidence-based clinical practice guideline for bone cement-augmented pedicle screw technique ( version 2025), based on current evidence. The guidelines put forward 8 recommendations regarding the clinical value, scope of application, and operational standards of the technique, aiming to provide evidence-based medical support and technical standardization for clinical decision-making.

Objective:To investigate the incidence of postoperative complications in Chinese patients with gastric or colorectal cancer, and to evaluate the risk factors for postoperative complications.Methods:This was a national, multicenter, prospective, registry-based, cohort study of data obtained from the database of the Prevalence of Abdominal Complications After Gastro- enterological Surgery (PACAGE) study sponsored by the China Gastrointestinal Cancer Surgical Union. The PACAGE database prospectively collected general demographic characteristics, protocols for perioperative treatment, and variables associated with postoperative complications in patients treated for gastric or colorectal cancer in 20 medical centers from December 2018 to December 2020. The patients were grouped according to the presence or absence of postoperative complications. Postoperative complications were categorized and graded in accordance with the expert consensus on postoperative complications in gastrointestinal oncology surgery and Clavien-Dindo grading criteria. The incidence of postoperative complications of different grades are presented as bar charts. Independent risk factors for occurrence of postoperative complications were identified by multifactorial unconditional logistic regression.Results:The study cohort comprised 3926 patients with gastric or colorectal cancer, 657 (16.7%) of whom had a total of 876 postoperative complications. Serious complications (Grade III and above) occurred in 4.0% of patients (156/3926). The rate of Grade V complications was 0.2% (7/3926). The cohort included 2271 patients with gastric cancer with a postoperative complication rate of 18.1% (412/2271) and serious complication rate of 4.7% (106/2271); and 1655 with colorectal cancer, with a postoperative complication rate of 14.8% (245/1655) and serious complication rate of 3.0% (50/1655). The incidences of anastomotic leakage in patients with gastric and colorectal cancer were 3.3% (74/2271) and 3.4% (56/1655), respectively. Abdominal infection was the most frequently occurring complication, accounting for 28.7% (164/572) and 39.5% (120/304) of postoperative complications in patients with gastric and colorectal cancer, respectively. The most frequently occurring grade of postoperative complication was Grade II, accounting for 65.4% (374/572) and 56.6% (172/304) of complications in patients with gastric and colorectal cancers, respectively. Multifactorial analysis identified (1) the following independent risk factors for postoperative complications in patients in the gastric cancer group: preoperative comorbidities (OR=2.54, 95%CI: 1.51-4.28, P<0.001), neoadjuvant therapy (OR=1.42, 95%CI:1.06-1.89, P=0.020), high American Society of Anesthesiologists (ASA) scores (ASA score 2 points:OR=1.60, 95% CI: 1.23-2.07, P<0.001, ASA score ≥3 points:OR=0.43, 95% CI: 0.25-0.73, P=0.002), operative time >180 minutes (OR=1.81, 95% CI: 1.42-2.31, P<0.001), intraoperative bleeding >50 mL (OR=1.29,95%CI: 1.01-1.63, P=0.038), and distal gastrectomy compared with total gastrectomy (OR=0.65,95%CI: 0.51-0.83, P<0.001); and (2) the following independent risk factors for postoperative complications in patients in the colorectal cancer group: female (OR=0.60, 95%CI: 0.44-0.80, P<0.001), preoperative comorbidities (OR=2.73, 95%CI: 1.25-5.99, P=0.030), neoadjuvant therapy (OR=1.83, 95%CI:1.23-2.72, P=0.008), laparoscopic surgery (OR=0.47, 95%CI: 0.30-0.72, P=0.022), and abdominoperineal resection compared with low anterior resection (OR=2.74, 95%CI: 1.71-4.41, P<0.001). Conclusion:Postoperative complications associated with various types of infection were the most frequent complications in patients with gastric or colorectal cancer. Although the risk factors for postoperative complications differed between patients with gastric cancer and those with colorectal cancer, the presence of preoperative comorbidities, administration of neoadjuvant therapy, and extent of surgical resection, were the commonest factors associated with postoperative complications in patients of both categories.

Objective:To investigate the prognosis and the factors that influence it in patients with non-gastric gastrointestinal stromal tumors (GISTs) who are at low risk of recurrence.Methods:This was a retrospective cohort study. Clinicopathologic and prognostic data from patients with non-gastric GISTs and at low risk of recurrence (i.e., very low-risk or low-risk according to the 2008 version of the Modified NIH Risk Classification), who attended 18 medical centers in China between January 2000 and June 2023, were collected. We excluded patients with a history of prior malignancy, concurrent primary malignancy, multiple GISTs, and those who had received preoperative imatinib. The study cohort comprised 1,571 patients with GISTs, 370 (23.6%) of whom were at very low-risk and 1,201 (76.4%) at low-risk of recurrence. The cohort included 799 (50.9%) men and 772 (49.1%) women of median age 57 (16–93) years. Patients were followed up to July 2024. The prognosis and its influencing factors were analyzed. Receiver operating characteristic curves for tumor diameter and Ki67 were established, and the sensitivity, specificity, area under the curve (AUC) and optimal cut-off value with 95% confidence intervals were calculated. Propensity score matching was implemented using the 1:1 nearest neighbor matching method with a matching tolerance of 0.02.Results:With a median follow-up of 63 (12–267) months, the 5- and 10-year overall survival (OS) rates of the 1,571 patients were 99.5% and 98.0%, respectively, and the 5- and 10-year disease-free survival (DFS) rates were 96.3% and 94.4%, respectively. During postoperative follow-up, 3.8% (60/1,571) patients had disease recurrence or metastasis, comprising 0.8% (3/370) in the very low-risk group and 4.7% (57/1,201) in the low-risk group. In the low-risk group, recurrence or metastasis occurred in 5.5% (25/457) of patients with duodenal GISTs, 3.9% (25/645) of those with small intestinal GISTs, 9.2% (6/65) of those with rectal GISTs, and 10.0% (1/10) of those with colonic GISTs. Among the 60 patients with metastases, 56.7% (34/60) of the metastases were located in the abdominal cavity, 53.3% (32/60) in the liver, and 3.3% (2/60) in bone. During the follow-up period, 13 patients (0.8%) died of disease. Receiver operating characteristic curves were plotted for tumor diameter and Ki67 and assessed using the Jordon index. This showed that the difference in DFS between the two groups was statistically significant when the cutoff value for tumor diameter was 3.5 cm (AUC 0.731, 95% CI: 0.670–0.793, sensitivity 77.7%, specificity 64.1%). Furthermore, the difference in DFS between the two groups was statistically significant when the cutoff value for Ki67 was 5% (AUC 0.693, 95% CI: 0.624–0.762, sensitivity 60.7%, specificity 65.3%). Multifactorial analysis revealed that tumor diameter ≥3.5 cm, Ki67 ≥5%, and R1 resection were independent risk factors for DFS in patients with non-gastric GISTs at low risk of recurrence (all P<0.05). Furthermore, age >57 years, Ki67 ≥5%, and R1 resection were also independent risk factors for OS in patients with non-gastric GISTs at low risk of recurrence (all P<0.05). We also grouped the patients according to whether they had received postoperative adjuvant treatment with imatinib for 1 or 3 years. This yielded 137 patients in the less than 1-year group, 139 in the 1-year plus group; and 44 in both the less than 3 years and 3-years plus group. After propensity score matching for age, tumor diameter, Ki67, and resection status, the differences in survival between the two groups were not statistically significant (all P>0.05). The 10-year DFS and OS were 87.5% and 95.5%, respectively, in the group treated with imatinib for less than 1 year and 88.5% and 97.8%, respectively, in the group treated for more than 1 year. The 10-year DFS and OS were 89.6% and 92.6%, respectively, in the group treated with imatinib for less than 3 years and 88.0% and 100.0%, respectively, in the group treated with imatinib for more than 3 years. Conclusion:The overall prognosis of primary, non-gastric, low recurrence risk GISTs is relatively favorable; however, recurrences and metastases do occur. Age, tumor diameter, Ki67, and R1 resection may affect the prognosis. For some patients with low risk GISTs, administration of adjuvant therapy with imatinib for an appropriate duration may help prevent recurrence and improve survival.

Objective:To investigate the incidence of postoperative complications in Chinese patients with gastric or colorectal cancer, and to evaluate the risk factors for postoperative complications.Methods:This was a national, multicenter, prospective, registry-based, cohort study of data obtained from the database of the Prevalence of Abdominal Complications After Gastro- enterological Surgery (PACAGE) study sponsored by the China Gastrointestinal Cancer Surgical Union. The PACAGE database prospectively collected general demographic characteristics, protocols for perioperative treatment, and variables associated with postoperative complications in patients treated for gastric or colorectal cancer in 20 medical centers from December 2018 to December 2020. The patients were grouped according to the presence or absence of postoperative complications. Postoperative complications were categorized and graded in accordance with the expert consensus on postoperative complications in gastrointestinal oncology surgery and Clavien-Dindo grading criteria. The incidence of postoperative complications of different grades are presented as bar charts. Independent risk factors for occurrence of postoperative complications were identified by multifactorial unconditional logistic regression.Results:The study cohort comprised 3926 patients with gastric or colorectal cancer, 657 (16.7%) of whom had a total of 876 postoperative complications. Serious complications (Grade III and above) occurred in 4.0% of patients (156/3926). The rate of Grade V complications was 0.2% (7/3926). The cohort included 2271 patients with gastric cancer with a postoperative complication rate of 18.1% (412/2271) and serious complication rate of 4.7% (106/2271); and 1655 with colorectal cancer, with a postoperative complication rate of 14.8% (245/1655) and serious complication rate of 3.0% (50/1655). The incidences of anastomotic leakage in patients with gastric and colorectal cancer were 3.3% (74/2271) and 3.4% (56/1655), respectively. Abdominal infection was the most frequently occurring complication, accounting for 28.7% (164/572) and 39.5% (120/304) of postoperative complications in patients with gastric and colorectal cancer, respectively. The most frequently occurring grade of postoperative complication was Grade II, accounting for 65.4% (374/572) and 56.6% (172/304) of complications in patients with gastric and colorectal cancers, respectively. Multifactorial analysis identified (1) the following independent risk factors for postoperative complications in patients in the gastric cancer group: preoperative comorbidities (OR=2.54, 95%CI: 1.51-4.28, P<0.001), neoadjuvant therapy (OR=1.42, 95%CI:1.06-1.89, P=0.020), high American Society of Anesthesiologists (ASA) scores (ASA score 2 points:OR=1.60, 95% CI: 1.23-2.07, P<0.001, ASA score ≥3 points:OR=0.43, 95% CI: 0.25-0.73, P=0.002), operative time >180 minutes (OR=1.81, 95% CI: 1.42-2.31, P<0.001), intraoperative bleeding >50 mL (OR=1.29,95%CI: 1.01-1.63, P=0.038), and distal gastrectomy compared with total gastrectomy (OR=0.65,95%CI: 0.51-0.83, P<0.001); and (2) the following independent risk factors for postoperative complications in patients in the colorectal cancer group: female (OR=0.60, 95%CI: 0.44-0.80, P<0.001), preoperative comorbidities (OR=2.73, 95%CI: 1.25-5.99, P=0.030), neoadjuvant therapy (OR=1.83, 95%CI:1.23-2.72, P=0.008), laparoscopic surgery (OR=0.47, 95%CI: 0.30-0.72, P=0.022), and abdominoperineal resection compared with low anterior resection (OR=2.74, 95%CI: 1.71-4.41, P<0.001). Conclusion:Postoperative complications associated with various types of infection were the most frequent complications in patients with gastric or colorectal cancer. Although the risk factors for postoperative complications differed between patients with gastric cancer and those with colorectal cancer, the presence of preoperative comorbidities, administration of neoadjuvant therapy, and extent of surgical resection, were the commonest factors associated with postoperative complications in patients of both categories.

Objective:To investigate the prognosis and the factors that influence it in patients with non-gastric gastrointestinal stromal tumors (GISTs) who are at low risk of recurrence.Methods:This was a retrospective cohort study. Clinicopathologic and prognostic data from patients with non-gastric GISTs and at low risk of recurrence (i.e., very low-risk or low-risk according to the 2008 version of the Modified NIH Risk Classification), who attended 18 medical centers in China between January 2000 and June 2023, were collected. We excluded patients with a history of prior malignancy, concurrent primary malignancy, multiple GISTs, and those who had received preoperative imatinib. The study cohort comprised 1,571 patients with GISTs, 370 (23.6%) of whom were at very low-risk and 1,201 (76.4%) at low-risk of recurrence. The cohort included 799 (50.9%) men and 772 (49.1%) women of median age 57 (16–93) years. Patients were followed up to July 2024. The prognosis and its influencing factors were analyzed. Receiver operating characteristic curves for tumor diameter and Ki67 were established, and the sensitivity, specificity, area under the curve (AUC) and optimal cut-off value with 95% confidence intervals were calculated. Propensity score matching was implemented using the 1:1 nearest neighbor matching method with a matching tolerance of 0.02.Results:With a median follow-up of 63 (12–267) months, the 5- and 10-year overall survival (OS) rates of the 1,571 patients were 99.5% and 98.0%, respectively, and the 5- and 10-year disease-free survival (DFS) rates were 96.3% and 94.4%, respectively. During postoperative follow-up, 3.8% (60/1,571) patients had disease recurrence or metastasis, comprising 0.8% (3/370) in the very low-risk group and 4.7% (57/1,201) in the low-risk group. In the low-risk group, recurrence or metastasis occurred in 5.5% (25/457) of patients with duodenal GISTs, 3.9% (25/645) of those with small intestinal GISTs, 9.2% (6/65) of those with rectal GISTs, and 10.0% (1/10) of those with colonic GISTs. Among the 60 patients with metastases, 56.7% (34/60) of the metastases were located in the abdominal cavity, 53.3% (32/60) in the liver, and 3.3% (2/60) in bone. During the follow-up period, 13 patients (0.8%) died of disease. Receiver operating characteristic curves were plotted for tumor diameter and Ki67 and assessed using the Jordon index. This showed that the difference in DFS between the two groups was statistically significant when the cutoff value for tumor diameter was 3.5 cm (AUC 0.731, 95% CI: 0.670–0.793, sensitivity 77.7%, specificity 64.1%). Furthermore, the difference in DFS between the two groups was statistically significant when the cutoff value for Ki67 was 5% (AUC 0.693, 95% CI: 0.624–0.762, sensitivity 60.7%, specificity 65.3%). Multifactorial analysis revealed that tumor diameter ≥3.5 cm, Ki67 ≥5%, and R1 resection were independent risk factors for DFS in patients with non-gastric GISTs at low risk of recurrence (all P<0.05). Furthermore, age >57 years, Ki67 ≥5%, and R1 resection were also independent risk factors for OS in patients with non-gastric GISTs at low risk of recurrence (all P<0.05). We also grouped the patients according to whether they had received postoperative adjuvant treatment with imatinib for 1 or 3 years. This yielded 137 patients in the less than 1-year group, 139 in the 1-year plus group; and 44 in both the less than 3 years and 3-years plus group. After propensity score matching for age, tumor diameter, Ki67, and resection status, the differences in survival between the two groups were not statistically significant (all P>0.05). The 10-year DFS and OS were 87.5% and 95.5%, respectively, in the group treated with imatinib for less than 1 year and 88.5% and 97.8%, respectively, in the group treated for more than 1 year. The 10-year DFS and OS were 89.6% and 92.6%, respectively, in the group treated with imatinib for less than 3 years and 88.0% and 100.0%, respectively, in the group treated with imatinib for more than 3 years. Conclusion:The overall prognosis of primary, non-gastric, low recurrence risk GISTs is relatively favorable; however, recurrences and metastases do occur. Age, tumor diameter, Ki67, and R1 resection may affect the prognosis. For some patients with low risk GISTs, administration of adjuvant therapy with imatinib for an appropriate duration may help prevent recurrence and improve survival.

Humans ; Esophageal Squamous Cell Carcinoma/pathology* ; Esophageal Neoplasms/pathology* ; Carcinoma, Squamous Cell/pathology* ; Precancerous Conditions/pathology* ; Early Diagnosis