1.Application of integer lifting wavelet transform and subblock coding to medical image compression.
Xiaoqi LU ; Xiaozhao XU ; Lidong YANG
Journal of Biomedical Engineering 2008;25(2):241-245
The method of subblock coding for medical image compression is presented by means of the integer lifting wavelet transform. The integer lifting wavelet transform has better effects on improving the processing speed; it can achieve wavelet transform for arbitrary size image and accomplish the transform at current position; furthermore, it can save memory space. The lifting algorithm can deal with the lossless compression and loss compression of image simultaneously, so it is adapted to telemedicine system and medical image compression system. The compression method based on image subblock coding can not only realize controlling BR (bit ratio), but also realize SNR (signal noise ratio) and suit for progressive transform.
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Data Compression
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methods
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Humans
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Image Interpretation, Computer-Assisted
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methods
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Information Storage and Retrieval
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methods
2.The application of multi-tissue transplantation in the surgical repair of eyelid divided nevus in plastic surgery
Sisi LUO ; Xiaozhao LU ; Zhe YANG ; Ning MA ; Sen CHEN ; Yangqun LI
Chinese Journal of Plastic Surgery 2024;40(3):300-306
Objective:To investigate the clinical efficacy of different surgical approaches for repairing eyelid coloboma.Methods:Patients with the divided nevus of eyelid treated at Hypospadias Plastic Surgery Center, Plastic Surgery Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, from January 2005 to January 2022 were included. The surgeries were categorized into 4 types. (1) Direct excision and suture. (2) Local skin grafts: covering the defect with split- or full-thickness skin grafts according to the size of the defect on the upper and lower eyelids. (3) Combined skin grafts with orbicularis oculi myocutaneous flap: grafting skin flaps for defects on the upper eyelid and near the lower eyelid, and temporal area skin flaps based on the same side orbicularis oculi muscle pedicle for lower eyelid defects. (4) Temporal area expanded flap based on the orbicularis oculi muscle combined with skin grafts: the surgery was divided into two stages, the first stage involves the placement of an expander in the temporal area of the affected side, and the second stage involves the removal of the expander, excision of eyelid lesion tissue and formation of an island-shaped skin flap with the orbital part of the orbicularis oculi muscle pedicle as the pedicle, which was rotated 180° to cover the lower eyelid defect. Defects near the upper and lower eyelid margins were still covered with skin grafts. Follow-up was conducted through outpatient visits, telephone calls, and WeChat messaging to assess facial appearance postoperatively. SPSS 22.0 statistical software was used for analysis, and the measurement data were expressed as Mean±SD, the count data were expressed as percentage, and the comparison of preoperative and postoperative was calculated by aesthetic and functional status of facial soft-tissue deformities (A&F scores) within the group was performed by paired t-test, the difference was considered statistically significant at P<0.05. Results:A total of 34 patients were included; average age was 17.7±15.3 years. The size of the lesions varied from the smallest nevus measuring 0.3 cm × 0.2 cm and the largest measuring 14.0 cm × 14.0 cm. Direct excision with suturing was performed in 6 cases, among which 2 cases received simultaneous double eyelid surgery, the postoperative A&F score (4.54 ± 1.32) was higher than the preoperative (3.28 ± 0.98) score, the difference was not statistically significant ( P>0.05). The skin graft was performed in 10 cases, the postoperative A&F score (5.13 ± 1.59) was higher than the preoperative (2.25 ± 1.59), the difference was not statistically significant ( P>0.05). The skin graft combined with using orbicularis oculi muscle skin flap was performed in 7 cases, the postoperative A&F score of our patients (5.54 ±1.46) was significantly higher than the preoperative (2.18 ±1.61 ), the difference was statistically significant ( P<0.05). The skin graft combined with the expanded temporal area flap based on the orbicularis oculi muscle was performed in 11 cases, the A&F score of our patients after repair (4.95 ±0.60) was improved compared with the preoperative (2.18±1.48) score, and the difference was not statistically significant ( P>0.05). Twenty-eight patients were followed up for 8 to 81 months while 6 cases lost due to change of contact information, among whom three developed secondary ectropion of the lower eyelid, three experienced recurrence of nevi in the incision and grafting area, two exhibited significant pigmentation in the grafting area, and one developed secondary ptosis of the upper eyelid, while the rest of the patients were satisfied with the repair results. Conclusion:Surgical excision is the only effective treatment for eyelid cleft nevi with different clinical presentations. Covering defects on the upper and lower eyelids with different tissue transplantation method can disperse the entire nevus, resulting in more stable long-term repair effects and a more natural appearance. The combination of an orbicularis muscle flap and a free skin graft provides more stable result in the plastic surgery of medium to large eyelid split nevi. Free skin grafting of the upper and lower lids near the margins, and flap grafting of the lower lids are more consistent with the physiological state of the upper and lower lids, and the combination of different tissue grafting method can make the appearance of the face more reasonable.
3.The application of multi-tissue transplantation in the surgical repair of eyelid divided nevus in plastic surgery
Sisi LUO ; Xiaozhao LU ; Zhe YANG ; Ning MA ; Sen CHEN ; Yangqun LI
Chinese Journal of Plastic Surgery 2024;40(3):300-306
Objective:To investigate the clinical efficacy of different surgical approaches for repairing eyelid coloboma.Methods:Patients with the divided nevus of eyelid treated at Hypospadias Plastic Surgery Center, Plastic Surgery Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, from January 2005 to January 2022 were included. The surgeries were categorized into 4 types. (1) Direct excision and suture. (2) Local skin grafts: covering the defect with split- or full-thickness skin grafts according to the size of the defect on the upper and lower eyelids. (3) Combined skin grafts with orbicularis oculi myocutaneous flap: grafting skin flaps for defects on the upper eyelid and near the lower eyelid, and temporal area skin flaps based on the same side orbicularis oculi muscle pedicle for lower eyelid defects. (4) Temporal area expanded flap based on the orbicularis oculi muscle combined with skin grafts: the surgery was divided into two stages, the first stage involves the placement of an expander in the temporal area of the affected side, and the second stage involves the removal of the expander, excision of eyelid lesion tissue and formation of an island-shaped skin flap with the orbital part of the orbicularis oculi muscle pedicle as the pedicle, which was rotated 180° to cover the lower eyelid defect. Defects near the upper and lower eyelid margins were still covered with skin grafts. Follow-up was conducted through outpatient visits, telephone calls, and WeChat messaging to assess facial appearance postoperatively. SPSS 22.0 statistical software was used for analysis, and the measurement data were expressed as Mean±SD, the count data were expressed as percentage, and the comparison of preoperative and postoperative was calculated by aesthetic and functional status of facial soft-tissue deformities (A&F scores) within the group was performed by paired t-test, the difference was considered statistically significant at P<0.05. Results:A total of 34 patients were included; average age was 17.7±15.3 years. The size of the lesions varied from the smallest nevus measuring 0.3 cm × 0.2 cm and the largest measuring 14.0 cm × 14.0 cm. Direct excision with suturing was performed in 6 cases, among which 2 cases received simultaneous double eyelid surgery, the postoperative A&F score (4.54 ± 1.32) was higher than the preoperative (3.28 ± 0.98) score, the difference was not statistically significant ( P>0.05). The skin graft was performed in 10 cases, the postoperative A&F score (5.13 ± 1.59) was higher than the preoperative (2.25 ± 1.59), the difference was not statistically significant ( P>0.05). The skin graft combined with using orbicularis oculi muscle skin flap was performed in 7 cases, the postoperative A&F score of our patients (5.54 ±1.46) was significantly higher than the preoperative (2.18 ±1.61 ), the difference was statistically significant ( P<0.05). The skin graft combined with the expanded temporal area flap based on the orbicularis oculi muscle was performed in 11 cases, the A&F score of our patients after repair (4.95 ±0.60) was improved compared with the preoperative (2.18±1.48) score, and the difference was not statistically significant ( P>0.05). Twenty-eight patients were followed up for 8 to 81 months while 6 cases lost due to change of contact information, among whom three developed secondary ectropion of the lower eyelid, three experienced recurrence of nevi in the incision and grafting area, two exhibited significant pigmentation in the grafting area, and one developed secondary ptosis of the upper eyelid, while the rest of the patients were satisfied with the repair results. Conclusion:Surgical excision is the only effective treatment for eyelid cleft nevi with different clinical presentations. Covering defects on the upper and lower eyelids with different tissue transplantation method can disperse the entire nevus, resulting in more stable long-term repair effects and a more natural appearance. The combination of an orbicularis muscle flap and a free skin graft provides more stable result in the plastic surgery of medium to large eyelid split nevi. Free skin grafting of the upper and lower lids near the margins, and flap grafting of the lower lids are more consistent with the physiological state of the upper and lower lids, and the combination of different tissue grafting method can make the appearance of the face more reasonable.
4.Diagnostic accuracy of 3.0T high-resolution MRI for assessment mesorectal lymph node metastases in patients with rectal cancer.
Yan CHEN ; Xinyue YANG ; Baolan LU ; Xiaojuan XIAO ; Xiaozhao ZHUANG ; Shenping YU
Chinese Journal of Gastrointestinal Surgery 2018;21(7):786-792
OBJECTIVETo evaluate the diagnostic value of 3.0T high-resolution MRI in mesorectal lymph node metastasis of rectal cancer.
METHODSThe images and postoperative pathological data of patients with pathologically diagnosed rectal cancer who underwent prospective 3.0T two dimensional high-resolution MRI rectal examinations and surgery within two weeks after MRI examination at the First Affiliated Hospital, Sun Yat-sen University from November 2015 to November 2016 were retrospectively collected. Patients who received preoperative neoadjuvant therapy and those who did not undergo operation after MRI examination were excluded. The MRI sequences included high-resolution sagittal, coronal and oblique axial T2 weighted image (T2WI) (repetition time/echo time, 3000-4000 ms/77-87 ms; slice thickness/gap, 3 mm/0 mm; field of view, 18-22 cm). Two abdominal MRI radiologists independently assessed the morphology, margin, signal of all visible mesorectal nodes, measured their minor axes (three times for each radiologist) and gave estimation of the malignancy. The criteria of metastatic nodes on high-resolution MRI T2WI were nodes with irregular shape, ill-defined border and/or heterogeneous signal. The results of MRI diagnosis were compared with postoperative pathology. The sensitivity, specificity, accuracy, positive predictive value(PPV) and negative predictive value(NPV) of mesorectal nodes and nodes with different short-axis diameter ranges were calculated to evaluate the diagnostic efficiency of high-resolution MRI. Kappa statistics was used to evaluate the agreement for per node and for per patient between high-resolution MRI and pathological results. A Kappa value of 0-0.20 indicated poor agreement; 0.21-0.40 fair agreement; 0.41-0.60 moderate agreement; 0.61-0.80 good agreement; and 0.81-1.00 excellent agreement.
RESULTSA total of 81 patients were enrolled in the retrospective cohort study, including 50 males and 31 females with age of (59.3±11.1) years. Histopathology showed 1 case of well differentiated adenocarcinoma, 63 of moderately differentiated adenocarcinoma, 9 of moderately to poorly differentiated adenocarcinoma, 2 of poorly differentiated adenocarcinoma, 3 of mucinous adenocarcinoma and 3 of tubulovillous adenocarcinoma. Histopathological staging showed 2 cases in T1 stage, 20 in T2 stage, 45 in T3 stage and 14 in T4 stage; 34 in N0 stage, 40 in N1 stage and 7 in N2 stage; 76 in M0 stage and 5 in M1 stage. A total of 377 nodes were included in the node-by-node evaluation, of which 168 (44.6%) nodes were metastatic from 58.0% (47/81) patients. The median short-axis diameter was 5.4(2.4-18.6) mm in metastatic nodes, which was significantly larger than 3.8 (2.0-8.7) mm in non-metastatic nodes[Z=10.586, P=0.000]. The sensitivity, specificity, accuracy, PPV and NPV were 74.4% (125/168), 94.7% (198/209), 85.7% (323/377), 91.9% (125/136) and 82.2% (198/241), respectively. The Kappa values between high-resolution MRI and histopathological diagnosis for node-by-node and patient-by-patient were 0.71 and 0.70 respectively, indicating good agreements. Fourteen nodes >10 mm were all metastatic. The results of high-resolution MRI for nodal status were consistent with the results of histopathological diagnosis, and the sensitivity, accuracy and PPV were all 100.0%. Among 124 nodes with short-axis diameter of 5-10 mm, 95 (76.6%) were metastatic, and the sensitivity, specificity, accuracy, PPV and NPV were 78.9% (75/95), 86.2% (25/29), 80.6% (100/124), 94.9% (75/79) and 55.6% (25/45), respectively. The agreement was fair (Kappa value 0.55) between high-resolution MRI and histopathological diagnosis. Among 239 nodes with short-axis diameter ≤5 mm, 59(24.7%) were metastatic, and the sensitivity, specificity, accuracy, PPV and NPV were 61.0% (36/59), 96.1%(173/180), 87.4%(209/239), 83.7%(36/43) and 88.3%(173/196), respectively. The agreement was good (Kappa value 0.63) between high-resolution MRI and histopathological diagnosis.
CONCLUSIONRectal high-resolution MRI has good diagnostic value for estimating metastatic mesorectal nodes by evaluating the morphology, margin and signal of nodes.
Aged ; Female ; Humans ; Lymph Nodes ; Lymphatic Metastasis ; diagnostic imaging ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Neoplasm Staging ; Prospective Studies ; Rectal Neoplasms ; diagnostic imaging ; pathology ; Retrospective Studies ; Sensitivity and Specificity
5.Efficacy evaluation of comprehensive treatment for chronic dacryocystitis with meibomian gland dysfunction
Yi ZHANG ; Xiaozhao YANG ; Hua YANG ; Xuan ZHENG ; Haiqing LU ; Chao LIU
International Eye Science 2024;24(11):1836-1841
AIM: To investigate the efficacy of lacrimal duct laser dacryoplasty combined with intubation and postoperative meibomian gland treatment in patients with chronic dacryocystitis complicated by meibomian gland dysfunction.METHODS: Data were collected from 128 patients with chronic dacryocystitis complicated by meibomian gland dysfunction treated at Xi'an No.1 Hospital from March 2021 to December 2022. All patients underwent lacrimal duct laser dacryoplasty combined with intubation. Postoperatively, those patients were randomly divided into two groups: group A(64 cases, without meibomian gland treatment)and group B(64 cases, with meibomian gland treatment). The lacrimal intubation was removed at 3 mo after surgery to evaluate the patency rate of lacrimal irrigation. Additionally, changes in the ocular surface disease index(OSDI)score, non-invasive tear film break-up time, tear meniscus height, conjunctival hyperemia analysis, meibomian gland analysis, tear lipid layer thickness, tear ferning test, and conjunctival impression cytology were compared between the two groups.RESULTS: The lacrimal irrigation patency rates in the group A and group B were 78.1% and 81.2% respectively, with no statistically significant difference between the two groups(P>0.05); compared with the group A, group B showed a significant extension in non-invasive tear breakup time at 3 mo after surgery, and the OSDI score, conjunctival hyperemia analysis, tear ferning test and conjunctival impression cytology grading were all significantly decreased(all P<0.05), while there was no significant difference in tear meniscus height, tear lipid layer thickness and meibomian gland loss score between the two groups(all P>0.05).CONCLUSION: Comprehensive treatment for patients with chronic dacryocystitis combined with meibomian gland dysfunction have improved patients' comfort, tear film stability, and reduces local inflammatory response. It is important to simultaneously address ocular surface microenvironment abnormalities during surgical treatment to achieve satisfactory efficacy.