Objective:To propose a novel radiotherapy marking method-the"#"-character method,which aimed at improving the accuracy and repeatability of positioning during radiotherapy.Methods:A specially"cross-shaped"stamp was designed by this study,which consisted of a handheld square base with a"cross-shaped"protrusion.Using this stamp,the extreme positions of end-expiration and end-inspiration were marked respectively at the laser-guided regions on the directly above and bilateral sides of the patient's body,and each position was printed a"+"character.Finally,a"#-shaped"signal was formed,which represented the full range of respiratory motion of patients.The study included two parts:surface displacement caused by respiration was simulated through a three-dimensional(3D)motion platform,which was used to conduct a phantom experiment for anthropomorphic dummy,A randomized controlled study involving 40 patients,who were treated between January and June 2024 at the Department of Radiotherapy,Cancer Hospital,Chinese Academy of Medical Sciences,were conducted.The cohort included 20 patients with breast tumor(Positioning the outer contour by exposing the chest)and 20 patients with thoracic tumor(fixed position of using thermoplastic film).These patients were divided into two groups for comparison,which received respectively the"#-shaped"method and the conventional"+-shaped"method.The cone-beam computed tomography(CBCT)images before treatment were used to compare the influences of the two kinds of marking methods on the positioning errors of patients with breast tumor and patients with thoracic tumor.Then,the statistical analysis was used to assess precision and accuracy of positioning.Results:The result of phantom experiment indicated that the positioning error of the"#-shaped"method was significantly better than that of the"+-shaped"method under various parameters of respiratory movement.Under three kinds of different respiratory cycles(3,4,and 5 seconds)and amplitudes(8,12,and 15 mm),the positioning errors of the"#-shaped"method were respectively(0.15±0.04)cm,(0.19±0.05)cm and(0.35±0.14)cm,while the"+-shaped"method were respectively(0.42±0.16)cm,(0.64±0.28)cm and(0.88±0.37)cm,and the differences were statistically significant(t=8.347,3.416,2.901,P<0.05).The results of actual patients indicated the positioning error[(0.97±0.32)cm]of the"#-shaped"method was significantly lower than[(1.62±0.47)cm]of the"+-shaped"method for patients with breast tumor(Positioning the outer contour by exposing the chest),and the difference was significant(t=3.615,P<0.05).On the other hand,the positioning error[(0.69±0.24)cm]of the"#-shaped"method was significantly lower than[(0.97±0.39)cm]of the"+-shaped"method for patients with thoracic tumor(fixed position of using thermoplastic film),and the difference also was significant(t=1.934,P<0.05).Conclusion:Compared to the conventional"+-shaped"method,the"#-shaped"method appears higher accuracy and repeatability during the positioning process of radiotherapy,which especially is suitable to the treatment for breast tumor and thoracic tumor that need accurately control the influences of respiratory motion.

Objective:To compare the accuracy of two-dimensional (2D) ultrasound with three-dimensional (3D) reconstruction and conventional 2D ultrasound in measuring bladder volume in pelvic tumor patients, using computed tomography (CT) as the reference.Methods:A set of bladder phantoms were constructed to compare CT and ultrasound measurements with actual injected volumes. Clinical data of 104 pelvic tumor patients who received radiotherapy at the Cancer Hospital, Chinese Academy of Medical Sciences between August and December 2023 were retrospectively analyzed. Portable transabdominal ultrasound was used to obtain the largest bladder cross-section, and the maximum diameters in the left-right (LR), anterior-posterior (AP), and superior-inferior (SI) directions (D LR, D AP, D SI) were measured. The 2D ultrasound volume was calculated as V=0.523 × D LR × D AP × D SI. Full-bladder transverse videos were recorded and processed in Matlab R2016a through frame extraction(60 images), followed by contrast enhancement, edge detection segmentation, cubic spline interpolation, and image smoothing to achieve 3D reconstruction. Paired t-tests, intraclass correlation coefficients (ICC), and Bland-Altman analyses were performed to assess systematic bias and consistency between ultrasound methods and CT. Multivariate linear regression was applied to evaluate the effects of slice thickness, posture, age, and other factors on CT measurements. Results:In the phantom study, deviations of 2D ultrasound and CT from actual injected volumes were (0.73±3.05) ml ( t=-0.48, P=0.667) and (1.52±11.27) ml ( t=0.17, P=0.875), with ICC values>0.999. In the clinical study, mean bladder volumes measured by 3D-reconstructed ultrasound, conventional 2D ultrasound, and CT were (373.5±153.31), (314.89±135.28), (382.82±157.57) ml, respectively. The 3D-reconstructed method showed excellent agreement with CT (ICC=0.98; Bland-Altman mean bias=-9.32 ml, P=0.096), while 2D ultrasound also showed good consistency (ICC=0.91), but significantly underestimated bladder volume (mean bias=-67.93 ml, P<0.001). Subgroup analysis revealed that 2D ultrasound had the best agreement with CT in the medium-volume group (200-500 ml, ICC=0.902), whereas agreement decreased in the small-volume (<200 ml, ICC=0.884) and large-volume (>500 ml, ICC=0.840) groups (all P<0.001). The 3D-reconstructed ultrasound maintained excellent consistency with CT across all subgroups (all ICC>0.95), and the measured bladder volume was not statistically significant. Multivariate regression showed that slice thickness, posture, age, sex, and surgical status had no significant effects on CT measurements. Conclusions:Ultrasound with 3D reconstruction enables accurate bladder volume monitoring through true 3D contour reconstruction, while conventional 2D ultrasound systematically underestimates bladder volume and requires correction.

ObjectiveTo analyze the influencing factors for recurrence in successfully treated pulmonary tuberculosis patients with isoniazid-resistant and rifampicin-sensitive in Shaoxing City, Zhejiang Province. MethodsData on general demographic information, treatment information and drug susceptibility test results for pulmonary tuberculosis patients admitted to the designated tuberculosis medical institutions and registered in the tuberculosis information management system was collected in Shaoxing City from January 2011 to August 2024. A total of 428 patients with isoniazid resistance (including isoniazid single resistance and multiple resistance) but who were successfully treated were included in the study. Information for the recurrence after successful treatment of the patients was analyzed. The Cox proportional hazards models were used to analyze the influencing factors of recurrence in patients. ResultsAmong the 428 successfully treated patients included in the study, 31 cases (accounting for 7.24%) had recurrence by the end of the observation period, with a recurrence rate density of 1.31 per 100 person-years and a median recurrence time of 0.99 (0.08, 8.27) years. Among the relapsed population, 51.61% of the patients relapsed within one year after successful treatment. 77.42% of the patients relapsed within two years after successful treatment. Multivariate Cox regression analysis showed that when isoniazid resistance was discovered, the diagnosis classification of relapse (HR=4.115, 95%CI: 1.734‒9.767) and positive 0-month sequence smear (HR=4.457, 95%CI: 1.053‒18.866) were risk factors for recurrence after successful treatment in patients. ConclusionRegular follow-up should be strengthened for at least two years after the successful treatment of isoniazid-resistant pulmonary tuberculosis patients. Special attention should be paid to the treatment effect and regular re-examination and monitoring after the end of the treatment course of isoniazid-resistant pulmonary tuberculosis patients who have been re-treated and were sputum smear positive at baseline, so as to prevent recurrence and disease progression in high-risk populations.

OBJECTIVE: To observe the clinical efficacy of acupuncture and moxibustion combined with medication in the treatment of functional constipation in elderly with yang deficiency and qi stagnation and its effect on emotional disorder. METHODS: A total of 86 elderly patients with functional constipation of yang deficiency and qi stagnation were randomly divided into an acupuncture and moxibustion group (43 cases, 1 case dropped out, 1 case was eliminated) and a medication group (43 cases, 1 case dropped out). The medication group was treated with lactulose oral solution, once a day；in the acupuncture and moxibustion group, on the basis of the treatment in the medication group, acupuncture at intestinal three points (bilateral Tianshu [ST25], Shangjuxu [ST37] and Guanyuan [CV4] were selected, 30 min each time, once every other day) combined with thunder-fire moxibustion (Shenque [CV8] was selected, 30 min each time, once every other day) was given. Both groups were treated for 4 weeks. Before and after treatment, the patient assessment of constipation symptoms (PAC-SYM) score, defecation situation (defecation interval time, defecation time, defecation frequency) and the scores of TCM syndrome, patient assessment of constipation quality of life (PAC-QOL), Pittsburgh sleep quality index (PSQI), self-rating anxiety scale (SAS), self-rating depression scale (SDS) were observed in the two groups. The clinical efficacy and safety of the two groups were evaluated. RESULTS: Compared before treatment, after treatment, the PAC-SYM scores, defecation interval time, defecation time, TCM syndrome scores, PAC-QOL scores, SAS scores and SDS scores in both groups were decreased (P<0.05), the defecation frequency was increased (P<0.05) in the two groups; the PSQI score in the acupuncture and moxibustion group was decreased (P<0.05). The PAC-SYM score, defecation interval time, defecation time, TCM syndrome score, PAC-QOL score, PSQI score, SAS score and SDS score after treatment in the acupuncture and moxibustion group were lower than those in the medication group (P<0.05), and the defecation frequency in the acupuncture and moxibustion group was higher than that in the medication group (P<0.05). The total effective rate of the acupuncture and moxibustion group was 92.7% (38/41), which was higher than 73.8% (31/42) in the medication group (P<0.05). The incidence of adverse reactions in the acupuncture and moxibustion group was 2.44% (1/41), while that in the medication group was 4.76% (2/42), there was no significant difference between the two groups (P>0.05). CONCLUSION Acupuncture and moxibustion combined with medication could improve the defecation situation, emotional disorder, quality of life in elderly patients with functional constipation of yang deficiency and qi stagnation.
Humans ; Moxibustion ; Constipation/drug therapy* ; Female ; Aged ; Male ; Acupuncture Therapy ; Treatment Outcome ; Qi ; Middle Aged ; Yang Deficiency/drug therapy* ; Aged, 80 and over ; Combined Modality Therapy ; Acupuncture Points

BACKGROUND: Enzalutamide, a second-generation androgen receptor (AR) pathway inhibitor, is widely used in the treatment of castration-resistant prostate cancer. However, after a period of enzalutamide treatment, patients inevitably develop drug resistance. In this study, we characterized leucine-rich repeated G-protein-coupled receptor 5 (LGR5) and explored its potential therapeutic value in prostate cancer. METHODS: A total of 142 pairs of tumor and adjacent formalin-fixed paraf-fin-embedded tissue samples from patients with prostate cancer were collected from the Pathology Department at Sun Yat-sen Memorial Hos-pital. LGR5 was screened by sequencing data of enzalutamide-resistant cell lines combined with sequencing data of lesions with different Gleason scores from the same patients. The biological function of LGR5 and its effect on enzalutamide resistance were investigated in vitro and in vivo . Glutathione-S-transferase (GST) pull-down, coimmunoprecipitation, Western blotting, and immunofluorescence assays were used to explore the specific binding mechanism of LGR5 and related pathway changes. RESULTS: LGR5 was significantly upregulated in prostate cancer and negatively correlated with poor patient prognosis. Overexpression of LGR5 promoted the malignant progression of prostate cancer and reduced sensitivity to enzalutamide in vitro and in vivo . LGR5 promoted the phosphorylation of glycogen synthase kinase-3β (GSK-3β) by binding heat shock protein 90,000 alpha B1 (HSP90AB1) and mediated the activation of the Wingless/integrated (WNT)/β-catenin signaling pathway. The increased β-catenin in the cytoplasm entered the nucleus and bound to the nuclear AR, promoting the transcription level of AR, which led to the enhanced tolerance of prostate cancer to enzalutamide. Reducing HSP90AB1 binding to LGR5 significantly enhanced sensitivity to enzalutamide. CONCLUSIONS LGR5 directly binds to HSP90AB1 and mediates GSK-3β phosphorylation, promoting AR expression by regulating the WNT/β-catenin signaling pathway, thereby conferring resistance to enzalutamide treatment in prostate cancer.
Male ; Humans ; Phenylthiohydantoin/pharmacology* ; Benzamides ; Receptors, G-Protein-Coupled/genetics* ; Nitriles ; Cell Line, Tumor ; HSP90 Heat-Shock Proteins/metabolism* ; Drug Resistance, Neoplasm/genetics* ; Prostatic Neoplasms/drug therapy* ; beta Catenin/metabolism* ; Receptors, Androgen/genetics* ; Animals ; Mice ; Wnt Signaling Pathway/physiology*

OBJECTIVE: To observe the protective effect of Fisetin on sepsis-associated brain injury and explore its possible mechanism from the perspective of ferroptosis. METHODS: Sprague-Dawley (SD) rats (6-8-week-old male) were randomly divided into three groups: sham operation group (Sham group), colonic ligation and puncture (CLP) induced sepsis model group (CLP group) and Fisetin preprocessing group (CLP+Fisetin group), with 18 rats in each group (12 for observing survival rate and 6 for indicator testing). The CLP+Fisetin group was given Fisetin solution 50 mg×kg^-1×d^-1 by gavage continuously for 5 days before CLP, with dimethyl sulfoxide (DMSO) as the solute, while Sham group and CLP group were given the same dose of DMSO. The model was established at 2 hours after the last gavage. The general condition of each group of rats were observed, and the 10-day mortality were record. The behavioral testing (new object recognition experiment, elevated cross maze experiment) were performed after 7 days of modeling. After 24 hours of modeling, nerve reflex scoring was performed, and then the rats were euthanized and brain tissue was collected. The pathological changes of brain tissue were observed under a microscope by hematoxylin-eosin (HE) staining, the deposition of iron ion in brain tissue was observed by Prussian blue staining. The content of iron in brain tissue was determined by tissue iron kit, and the content of malondialdehyde (MDA) in brain tissue was determined by colorimetry. The expressions of tumor necrosis factor-α (TNF-α), neuron damage marker S100β, nuclear factor E2-related factor 2 (Nrf2), heme oxygenases-1 (HO-1) and glutathione peroxidase 4 (GPX4) were detected by Western blotting. RESULTS: On day 10 post-operation, 12, 3, and 7 animals survived in the Sham group, CLP group, and CLP+Fisetin group, respectively. Compared with the Sham group, rats in the CLP group showed significantly decreased nerve reflex score, new object discrimination index and open arm dwell time. HE staining showed arranged disorderly of neuronal cells, cytoplasm deep staining, nuclear condensation, unclear structures, neuron loss, and significant inflammation in the hippocampus in the hippocampus. Prussian blue staining showed iron ion deposition in the brain tissue. The contents of iron and MDA in brain tissue were elevated, and the expressions of TNF-α and S100β were up-regulated, while the expressions of Nrf2, HO-1, and GPX4 were down-regulated. Compared with the CLP group, the CLP+Fisetin group showed significantly increased neurological reflex score (7.33±1.15 vs. 4.67±1.53), improved new object discrimination index (0.44±0.02 vs. 0.32±0.04), and longer open arm dwell time (minutes: 78.33±9.29 vs. 41.15±9.64). Neuronal cells in the hippocampus were more organized, with less cytoplasmic staining, nuclear condensation, reduced neuronal loss, and fewer inflammatory cells. Iron ion deposition was reduced, and the contents of iron ions and MDA in brain tissue were decreased [iron ion (μg/g): 151.27±14.90 vs. 224.69±17.64, MDA (μmol/g): 470.0±44.3 vs. 709.3±65.4]. The expressions of TNF-α and S100β were significantly decreased (TNF-α/GAPDH: 0.651±0.060 vs. 0.896±0.022, S100β/GAPDH: 0.685±0.032 vs. 0.902±0.014), while the expressions of Nrf2, HO-1, and GPX4 were significantly increased (Nrf2/GAPDH: 0.708±0.108 vs. 0.316±0.112, HO-1/GAPDH: 0.694±0.022 vs. 0.538±0.024, GPX4/GAPDH: 0.620±0.170 vs. 0.317±0.039). All differences were statistically significant (all P < 0.05). CONCLUSION Fisetin pretreatment can inhibit ferroptosis and reduce sepsis-associated brain injury by Nrf2/HO-1/GPX4 pathway.
Animals ; Ferroptosis/drug effects* ; Rats, Sprague-Dawley ; NF-E2-Related Factor 2/metabolism* ; Sepsis/complications* ; Male ; Rats ; Phospholipid Hydroperoxide Glutathione Peroxidase ; Neurons/drug effects* ; Signal Transduction ; Brain Injuries/metabolism* ; Flavonols ; Flavonoids/pharmacology* ; Heme Oxygenase-1/metabolism* ; Heme Oxygenase (Decyclizing)

Objective To investigate the effect and mechanism of melatonin in alleviating hypoxia-induced apoptosis in ovarian gra-nulosa cells.Methods Rat ovarian granulosa cells were isolated and divided into normoxic,hypoxic,and melatonin groups.Hypoxia-induced injury models were established in the hypoxic and melatonin groups,and granulosa cells in the melatonin group were treated with melatonin.A total of 24 rats were randomized into the control,model,and intervention groups(n=8 per group).Rat models of declining ovarian function induced by long-term hypoxia were established in the model and intervention groups.The rats in the intervention group were intraperitoneally injected with melatonin.Cell proliferation was measured using a CCK-8 assay,and lactate secretion and HIF-1αprotein with a specific kit,respectively.The levels of estradiol and progesterone in the cell supernatant and rat serum were detected using ELISA.Granulosa cell apoptosis was detected by flow cytometry,ovarian morphology by HE staining,and Bax and caspase-3 expression by Western blotting.Results Compared with the normoxic group,the hypoxic group exhibited decreased granulosa cell proliferation,increased apoptosis,elevated lactate and HIF-1α levels,and reduced estradiol and progesterone levels(P＜0.05).Compared with hypoxic group,these changes were significantly reversed in the molatonin group(P＜0.05).Compared with the control group,the model group showed increased lactate,HIF-1α,Bax,and caspase-3 levels,decreased estradiol and progesterone levels,and reduced follicles.Compared with the model group,all the indicators were ameliorated in the intervention group(P＜0.05).Conclusion Melatonin alleviated hypoxia-induced granulosa cell apoptosis and promoted the recovery of ovarian function.

Objective To investigate the effect and mechanism of melatonin in alleviating hypoxia-induced apoptosis in ovarian gra-nulosa cells.Methods Rat ovarian granulosa cells were isolated and divided into normoxic,hypoxic,and melatonin groups.Hypoxia-induced injury models were established in the hypoxic and melatonin groups,and granulosa cells in the melatonin group were treated with melatonin.A total of 24 rats were randomized into the control,model,and intervention groups(n=8 per group).Rat models of declining ovarian function induced by long-term hypoxia were established in the model and intervention groups.The rats in the intervention group were intraperitoneally injected with melatonin.Cell proliferation was measured using a CCK-8 assay,and lactate secretion and HIF-1αprotein with a specific kit,respectively.The levels of estradiol and progesterone in the cell supernatant and rat serum were detected using ELISA.Granulosa cell apoptosis was detected by flow cytometry,ovarian morphology by HE staining,and Bax and caspase-3 expression by Western blotting.Results Compared with the normoxic group,the hypoxic group exhibited decreased granulosa cell proliferation,increased apoptosis,elevated lactate and HIF-1α levels,and reduced estradiol and progesterone levels(P＜0.05).Compared with hypoxic group,these changes were significantly reversed in the molatonin group(P＜0.05).Compared with the control group,the model group showed increased lactate,HIF-1α,Bax,and caspase-3 levels,decreased estradiol and progesterone levels,and reduced follicles.Compared with the model group,all the indicators were ameliorated in the intervention group(P＜0.05).Conclusion Melatonin alleviated hypoxia-induced granulosa cell apoptosis and promoted the recovery of ovarian function.

Objective:To propose a novel radiotherapy marking method-the"#"-character method,which aimed at improving the accuracy and repeatability of positioning during radiotherapy.Methods:A specially"cross-shaped"stamp was designed by this study,which consisted of a handheld square base with a"cross-shaped"protrusion.Using this stamp,the extreme positions of end-expiration and end-inspiration were marked respectively at the laser-guided regions on the directly above and bilateral sides of the patient's body,and each position was printed a"+"character.Finally,a"#-shaped"signal was formed,which represented the full range of respiratory motion of patients.The study included two parts:surface displacement caused by respiration was simulated through a three-dimensional(3D)motion platform,which was used to conduct a phantom experiment for anthropomorphic dummy,A randomized controlled study involving 40 patients,who were treated between January and June 2024 at the Department of Radiotherapy,Cancer Hospital,Chinese Academy of Medical Sciences,were conducted.The cohort included 20 patients with breast tumor(Positioning the outer contour by exposing the chest)and 20 patients with thoracic tumor(fixed position of using thermoplastic film).These patients were divided into two groups for comparison,which received respectively the"#-shaped"method and the conventional"+-shaped"method.The cone-beam computed tomography(CBCT)images before treatment were used to compare the influences of the two kinds of marking methods on the positioning errors of patients with breast tumor and patients with thoracic tumor.Then,the statistical analysis was used to assess precision and accuracy of positioning.Results:The result of phantom experiment indicated that the positioning error of the"#-shaped"method was significantly better than that of the"+-shaped"method under various parameters of respiratory movement.Under three kinds of different respiratory cycles(3,4,and 5 seconds)and amplitudes(8,12,and 15 mm),the positioning errors of the"#-shaped"method were respectively(0.15±0.04)cm,(0.19±0.05)cm and(0.35±0.14)cm,while the"+-shaped"method were respectively(0.42±0.16)cm,(0.64±0.28)cm and(0.88±0.37)cm,and the differences were statistically significant(t=8.347,3.416,2.901,P<0.05).The results of actual patients indicated the positioning error[(0.97±0.32)cm]of the"#-shaped"method was significantly lower than[(1.62±0.47)cm]of the"+-shaped"method for patients with breast tumor(Positioning the outer contour by exposing the chest),and the difference was significant(t=3.615,P<0.05).On the other hand,the positioning error[(0.69±0.24)cm]of the"#-shaped"method was significantly lower than[(0.97±0.39)cm]of the"+-shaped"method for patients with thoracic tumor(fixed position of using thermoplastic film),and the difference also was significant(t=1.934,P<0.05).Conclusion:Compared to the conventional"+-shaped"method,the"#-shaped"method appears higher accuracy and repeatability during the positioning process of radiotherapy,which especially is suitable to the treatment for breast tumor and thoracic tumor that need accurately control the influences of respiratory motion.

Objective:To compare the accuracy of two-dimensional (2D) ultrasound with three-dimensional (3D) reconstruction and conventional 2D ultrasound in measuring bladder volume in pelvic tumor patients, using computed tomography (CT) as the reference.Methods:A set of bladder phantoms were constructed to compare CT and ultrasound measurements with actual injected volumes. Clinical data of 104 pelvic tumor patients who received radiotherapy at the Cancer Hospital, Chinese Academy of Medical Sciences between August and December 2023 were retrospectively analyzed. Portable transabdominal ultrasound was used to obtain the largest bladder cross-section, and the maximum diameters in the left-right (LR), anterior-posterior (AP), and superior-inferior (SI) directions (D LR, D AP, D SI) were measured. The 2D ultrasound volume was calculated as V=0.523 × D LR × D AP × D SI. Full-bladder transverse videos were recorded and processed in Matlab R2016a through frame extraction(60 images), followed by contrast enhancement, edge detection segmentation, cubic spline interpolation, and image smoothing to achieve 3D reconstruction. Paired t-tests, intraclass correlation coefficients (ICC), and Bland-Altman analyses were performed to assess systematic bias and consistency between ultrasound methods and CT. Multivariate linear regression was applied to evaluate the effects of slice thickness, posture, age, and other factors on CT measurements. Results:In the phantom study, deviations of 2D ultrasound and CT from actual injected volumes were (0.73±3.05) ml ( t=-0.48, P=0.667) and (1.52±11.27) ml ( t=0.17, P=0.875), with ICC values>0.999. In the clinical study, mean bladder volumes measured by 3D-reconstructed ultrasound, conventional 2D ultrasound, and CT were (373.5±153.31), (314.89±135.28), (382.82±157.57) ml, respectively. The 3D-reconstructed method showed excellent agreement with CT (ICC=0.98; Bland-Altman mean bias=-9.32 ml, P=0.096), while 2D ultrasound also showed good consistency (ICC=0.91), but significantly underestimated bladder volume (mean bias=-67.93 ml, P<0.001). Subgroup analysis revealed that 2D ultrasound had the best agreement with CT in the medium-volume group (200-500 ml, ICC=0.902), whereas agreement decreased in the small-volume (<200 ml, ICC=0.884) and large-volume (>500 ml, ICC=0.840) groups (all P<0.001). The 3D-reconstructed ultrasound maintained excellent consistency with CT across all subgroups (all ICC>0.95), and the measured bladder volume was not statistically significant. Multivariate regression showed that slice thickness, posture, age, sex, and surgical status had no significant effects on CT measurements. Conclusions:Ultrasound with 3D reconstruction enables accurate bladder volume monitoring through true 3D contour reconstruction, while conventional 2D ultrasound systematically underestimates bladder volume and requires correction.