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BACKGROUND: It is debatable whether the area of substantia nigra hyperechogenicity (SN+) in transcranial sonography (TCS) is related to Parkinson's disease (PD) severity. Iron deposition, which is associated with the formation of SN+, may have different effects on dopamine nerve function as PD progresses. However, little research has explored the association between the SN + area and disease severity of PD in stages. METHODS: 612 PD patients with sufficient bone window were retrospectively included from a PD database, and disease severity was assessed by the Unified Parkinson's Disease Rating Scale (UPDRS) scores. Based on the Hoehn and Yahr (H-Y) scale, we classified the patients into seven groups (H-Y stage 1, 1.5, 2, 2.5, 3, 4, and 5) and then analyzed the correlations between the SN + area and the UPDRS scores separately. RESULTS: Our results indicated a U-shaped relationship between the initial-SN + area and disease severity in PD: In the H-Y stage 1 group, the initial-SN + area was negatively correlated with the UPDRS total score (r = - 0.456, p < 0.001) and UPDRS-III score (r = - 0.497, p < 0.001). No correlation was observed in the groups of H-Y stages 1.5, 2, and 2.5. In the groups of H-Y stage ≥ 3, the initial-SN + area was positively correlated with the UPDRS total score and UPDRS-III score, with strongest correlation in the H-Y stage 5 group (all p values < 0.05). Moreover, the larger SN + area and average SN + area showed a similar evolutionary trend of correlation with UPDRS total score and UPDRS-III score. CONCLUSIONS: Our study indicated a U-shaped correlation between the SN + area with the UPDRS total score and UPDRS-III score as H-Y stage progressed. The evolution of the correlation may reflect the evolution of underlying pathological mechanisms related to iron deposition in the substantia nigra.
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OBJECTIVES: This study explored the characteristics of muscle stiffness of lower gastrocnemius in resting and exercise states in patients with postural instability gait difficulty (PIGD) and tremor dominant (TD) Parkinson's disease patients using shear wave elastography (SWE). DATA AND METHODS: 75 PD patients from the Department of Parkinson's Disease Center in the Hospital from September 2021 to December 2022 were prospectively included, including 44 patients with PIGD and 31 with TD. In the same period, 40 healthy subjects matching gender and age were included as the control group. SWE was used to detect Young's modulus of both sides (right and left, R- and L-) of the lateral head of the gastrocnemius in resting (YM1) and exerciser states (YM2) in all participants and the absolute difference Young's modulus between resting and exercise state (ΔYM) was calculated. RESULTS: R-YM2 and R-ΔYM were the highest in the normal controls, followed by the TD group, and lowest in the PIGD group. There were no differences in L-YM2 and L-ΔYM between the PIGD group and the TD group (all p > 0.05), but they were lower than those in the normal control group (all p < 0.05). In addition, R-YM2 and R-ΔYM were negatively correlated with disease duration and UPDRS III scores in the PIGD group (all p < 0.05). R-ΔYM has the highest value in the differential diagnosis of PIGD and TD patients. The area under the receiver operating characteristic curve (ROC) curve is 0.812 (95%CI, 0.730-0.893), and the diagnostic threshold is 120.5 Kpa with a sensitivity of 63.6%, a specificity of 90.1%, a positive predictive of 80%, and a negative predictive value of 80%. CONCLUSION: Shear wave elastography is a sensitive ultrasound method for evaluating muscle strength in patients with PIGD and TD. It also provides a new biological indicator to distinguish between different phenotypes of patients with PD.
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BACKGROUND: Subchorionic hematoma (SCH) is a common complication in early pregnancy characterized by the accumulation of blood between the uterine wall and the chorionic membrane. SCH can lead to adverse pregnancy outcomes such as miscarriage, preterm birth, and other complications. Early detection and accurate assessment of SCH are crucial for appropriate management and improved pregnancy outcomes. AIM: To evaluate the diagnostic efficacy of virtual organ computer-assisted analysis (VOCAL) in measuring the volume ratio of SCH to gestational sac (GS) combined with serum progesterone on early pregnancy outcomes in patients with SCH. METHODS: A total of 153 patients with SCH in their first-trimester pregnancies between 6 and 11 wk were enrolled. All patients were followed up until a gestational age of 20 wk. The parameters of transvaginal two-dimensional ultrasound, including the circumference of SCH (Cs), surface area of SCH (Ss), circumference of GS (Cg), and surface area of GS (Sg), and the parameters of VOCAL with transvaginal three-dimensional ultrasound, including the three-dimensional volume of SCH (3DVs) and GS (3DVg), were recorded. The size of the SCH and its ratio to the GS size (Cs/Cg, Ss/Sg, 3DVs/3DVg) were recorded and compared. RESULTS: Compared with those in the normal pregnancy group, the adverse pregnancy group had higher Cs/Cg, Ss/Sg, and 3DVs/3DVg ratios (P < 0.05). When 3DVs/3DVg was 0.220, the highest predictive performance predicted adverse pregnancy outcomes, resulting in an AUC of 0.767, and the sensitivity, specificity were 70.2%, 75% respectively. VOCAL measuring 3DVs/3DVg combined with serum progesterone gave a diagnostic AUC of 0.824 for early pregnancy outcome in SCH patients, with a high sensitivity of 82.1% and a specificity of 72.1%, which showed a significant difference between AUC. CONCLUSION: VOCAL-measured 3DVs/3DVg effectively quantifies the severity of SCH, while combined serum progesterone better predicts adverse pregnancy outcomes.
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OBJECTIVES: Transcranial sonography has been used as a valid neuroimaging tool to diagnose Parkinson's disease (PD). This study aimed to develop a modified transcranial sonography (TCS) technique based on a deep convolutional neural network (DCNN) model to predict Parkinson's disease. METHODS: This retrospective diagnostic study was conducted using 1529 transcranial sonography images collected from 854 patients with PD and 775 normal controls admitted to the Second Affiliated Hospital of Soochow University (Suzhou, Jiangsu, China) between September 2019 and May 2022. The data set was divided into training cohorts (570 PD patients and 541 normal controls), and the validation set (184 PD patients and 234 normal controls). Using these datasets, we developed four different DCNN models (ResNet18, ResNet50, ResNet152, and DenseNet121). We then assessed their diagnostic performance, including the area under the receiver operating characteristic (AUROC) curve, specificity, sensitivity, positive predictive value (PPV), negative predictive value (NPV), and F1 score and compared with traditional diagnostic criteria. RESULTS: Among the 1529 TCS images, 570 PD patients and 541 normal controls from 4 of 6 sonographers of the TCS team were selected as the training cohort, and 184 PD patients and 234 normal controls from the other 2 sonographers were chosen as the validation cohort. There were no sex and age differences between PD patients and normal control subjects in the training and validation cohorts (P values > 0.05). All DCNN models achieved good performance in distinguishing PD patients from normal control subjects on the validation datasets, with diagnostic AUROCs and accuracy of 0.949 (95% CI 0.925, 0.965) and 86.60 for the RestNet18 model, 0.949 (95% CI 0.929, 0.971) and 87.56 for ResNet50, 0.945 (95% CI 0.931, 0.969) and 88.04 for ResNet152, 0.953 (95% CI 0.935, 0.971) and 87.80 for DenseNet121, respectively. On the other hand, the diagnostic accuracy of the traditional diagnostic method was 82.30. The accuracy of all DCNN models was higher than that of traditional diagnostic method. Moreover, the 5k-fold cross-validation results in train datasets showed that these DCNN models are robust. CONCLUSION: The developed transcranial sonography-based DCNN models performed better than traditional diagnostic criteria, thus improving the sonographer's accuracy in diagnosing PD.
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OBJECTIVE: The correlation between substantia nigra (SN) hyperechogenicity on transcranial sonography (TCS) and serum iron metabolism parameters in patients with the postural instability gait difficulty (PIGD) subtype of Parkinson's disease (PD) was investigated so as to explore the pathological mechanism of SN hyperechogenicity. METHODS: The study enrolled 95 PIGD patients recruited by the Parkinson's Disease Specialty in the Second Affiliated Hospital of Soochow University during June 2019-2021. On the basis of the TCS results, the PIGD patients were assigned to the PD with SN hyperechogenicity (SN+) group (n = 60) and PD without SN hyperechogenicity (SN-) group (n = 35). Meanwhile, 49 sex- and age-matched healthy individuals were included in the control group. All participants underwent blood tests. Differences in the iron metabolism parameters among the three groups and the correlation between SN hyperechogenicity and serum iron metabolism parameters were analyzed. RESULTS: Serum ferritin, ceruloplasmin and transferrin levels were lower in the SN+ and SN- groups than in the control group (all p values <0.001). The serum ceruloplasmin level was lower in the SN+ group (0.23 [0.20, 0.25] g/L) than in the SN- group (0.25 [0.22, 0.29] g/L) (p = 0.001), and the proportion of patients with an abnormal ceruloplasmin level was higher in the SN+ group than in the SN- group (43.3% [26/60] vs. 14.3% [5/35], χ2 = 8.484, p = 0.004). Moreover, the SN hyperechogenicity area was negatively correlated with the serum transferrin level (r = -0.428, p < 0.001). CONCLUSION: Decreased serum ceruloplasmin levels may be associated with SN hyperechogenicity development in PIGD patients. The SN hyperechogenicity area is negatively correlated with the serum transferrin level.
Subject(s)
Parkinson Disease , Humans , Parkinson Disease/complications , Parkinson Disease/diagnostic imaging , Ceruloplasmin , Gait , Substantia Nigra/diagnostic imaging , Transferrins , IronABSTRACT
OBJECTIVE: This study aimed to explore the relationship between patients with obstructive sleep apnea (OSA) from subgroups of varying severity and substantia nigra (SN) hyperechogenicity as well as cerebral blood flow detected by transcranial sonography (TCS). The study also explored if there were differences in damage of the SN and in the cerebral blood flow between the bilateral sides. METHODS: Right-handed men diagnosed with OSA by polysomnography were recruited from August 2018 to August 2020. The included patients were divided into 3 subgroups (mild, moderate, and severe OSA), and all patients underwent TCS. RESULTS: Among the 157 study patients (30 with mild OSA, 25 moderate, and 102 severe), the overall prevalence of SN hyperechogenicity was 15% (23/157). The hyperechogenicity detection rates were 3% (4/157) in the right SN subgroup and 13% (20/157) in the left SN subgroup, which were significantly different. The left side always had reduced blood flow on TCS (P < 0.05). No correlation was observed between the severity of OSA and the detection rates of SN hyperechogenicity (P > 0.05). CONCLUSION: Patients with OSA showed a higher detection rate of SN hyperechogenicity on the left compared with the right side. The left middle cerebral arteries had reduced blood flow, which was consistent with the more severe damage of the left SN. No relationship was observed between the severity of OSA and the detection rate of SN hyperechogenicity or hemodynamic parameters.
Subject(s)
Sleep Apnea, Obstructive , Ultrasonography, Doppler, Transcranial , Male , Humans , Ultrasonography, Doppler, Transcranial/methods , Ultrasonography , Substantia Nigra , Sleep Apnea, Obstructive/diagnostic imagingABSTRACT
Our study focused on three aspects to determine whether bilateral substantia nigra hyperechogenicity (SN+) is asymmetrical, whether the asymmetry of SN+ is related to the clinical features and whether there is variation in SN+ asymmetry during the progression of Parkinson disease (PD). This follow-up study included 234 patients with PD, who were divided into tremor PD (TD, n = 67) and non-tremor PD (NTD, n = 167) groups based on the Unified Parkinson's Disease Rating Scale (UPDRS) Part III. All participants underwent transcranial sonography (TCS) and clinical assessment. In both the TD and NTD groups, the initial SN+ was larger than the non-initial SN+. The initial SN+ was associated with Hoehn and Yahr (H&Y) stage, PD duration and initial UPDRS III, and the SN+ asymmetry index was associated with motor asymmetry index in the TD group. In the NTD group, the initial SN+ was associated only with initial UPDRS III. After a 5-year follow-up, the area of SN+ on both sides was gradually inclining to symmetry in the NTD group. Our study determined that SN+ asymmetry could reflect asymmetrical characteristics of PD. Furthermore, we inferred that the dynamic change in SN+ asymmetry might reflect a dynamic change in motor asymmetry in the NTD group.
Subject(s)
Parkinson Disease , Follow-Up Studies , Humans , Substantia Nigra , Ultrasonography, Doppler, TranscranialABSTRACT
Purpose: Cognitive impairment (CI) is a common but debilitating non-motor symptom in Parkinson's disease (PD). Although cerebrovascular functions are related to cognitive performance in healthy individuals, such a relation in PD remains elusive. This study aims to assess the association between cerebrovascular function and cognitive performance in PD individuals. Patients and Methods: Two-hundred-and-one PD individuals were retrospectively included. They were subsequently divided into two groups: PD with normal cognition (PD-NC) and PD with CI (PD-CI). Cerebral hemodynamic characteristics of the middle cerebral arteries were assessed by transcranial ultrasound. The association between scores in each cognitive domain and cerebral hemodynamic parameters was further analyzed using regression analyses. Additionally, a binary logistic regression model with backward stepwise procedure was applied to build the model for discriminating CI in PD individuals. An independent dataset of additional 46 PD individuals was used further. Results: The PD-CI group showed a relatively lower end-diastolic blood flow velocity (EDV, p < 0.05) and a higher resistive index (RI, p < 0.05) compared to the PD-NC group. RI showed significant associations with the memory item score of Montreal Cognitive Assessment (p < 0.05). A model combining clinical and hemodynamic variables was established with optimal efficiency (area under the curve, AUC = 0.651). Further replication of the model in an independent dataset yielded a great consistency (AUC = 0.704). Conclusion: In our study, cerebrovascular functions were significantly associated with the cognitive performance in PD individuals, especially with the memory task. The established model was effective in identifying CI in PD individuals, which might be a potentially useful tool to screen the cognitive decline in PD individuals at an early stage of the disease. Further studies with larger sample sizes in different populations are warranted.
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Oil and gas reservoirs are of great significance for economic benefits. Faults act as important conduits for transporting hydrocarbons and as essential sealing conditions. The location and morphology of faults reflect changes in the shape of the strata, so fault interpretation of seismic data has been an essential task in oil and gas exploration and development. The traditional fault identification method is time-consuming and inaccurate with large uncertainties. This paper proposed a fault recognition method based on 3D-UNet that added attention mechanisms to a convolutional neural network (CNN). This approach takes advantage of the UNet end-to-end architecture and the attention mechanism to focus on essential areas and suppress irrelevant information, allowing the model to focus on more valuable features. A fault identification network for seismic data was proposed by combining the 3D-UNet architecture with the Squeeze-and-Excitation (SE) attention mechanism. The 3D-UNet architecture comprises two parts: encoding and decoding, and the network architecture realizes end-to-end training. At the same time, SE was used to focus on the advantages of feature channels, further improving the accuracy of the network. The model performance was evaluated using the synthetic dataset provided by Wu. Experimental results show that the proposed model has better prediction performance in terms of accuracy, better recognition continuity, and richer fault detail.
Subject(s)
Neural Networks, ComputerABSTRACT
PURPOSE: This study aimed to explore the clinical value of ultrasonic Doppler examination and contrast-enhanced ultrasound (US) in the circulation of septic acute kidney injury (AKI). METHODS: Patients with intensive care unit-related infection were divided into AKI group and control groups. The AKI group was divided into three subgroups according to the serum creatinine value: stage 1, stage 2, and stage 3. Relevant parameters and blood flow of the renal artery were measured, and further contrast-enhanced US was performed and time-intensity curve was analyzed. RESULTS: The renal blood flow (RBF) and time-averaged velocity decreased significantly in the AKI group compared with the control group (p = .021 and p = .001). The peak value decreased and time to peak (TTP) prolonged in the AKI group (p < .001). With the aggravation of the disease, the RBF decreased slightly among subgroups (p = 0.124). However, the peak value gradually decreased and the TTP prolonged (all p < .05). The multiple linear regression model showed that only PI, RI, and TTP were independently and linearly correlated with the serum creatinine value. CONCLUSIONS: Doppler US and contrast-enhanced US are of great help in the detection of condition changes and prognosis of patients with sepsis-induced AKI.
Subject(s)
Acute Kidney Injury , Sepsis , Acute Kidney Injury/diagnostic imaging , Creatinine , Female , Humans , Intensive Care Units , Kidney/diagnostic imaging , Male , Sepsis/complications , UltrasonographyABSTRACT
OBJECTIVES: This study aimed to explore the association of homocysteine (Hcy) with third ventricle (V3) dilatation and mesencephalic area (MA) atrophy as determined by transcranial sonography (TCS) in Parkinson's disease (PD) with cognitive impairment. METHODS: The final statistical analysis included 101 PD patients and 20 age- and sex-matched controls. Using the Movement Disorder Society (MDS) level II criteria for PD with cognitive impairment, we categorized the PD patients into PD with normal cognition group (PD) and PD with cognitive impairment group (PDC). All subjects underwent TCS and laboratory analysis. RESULTS: The V3 width (r = 0.349, P = 0.005) and the MA (r = -0.484, P < 0.001) were significantly correlated with the Hcy concentration in the PDC patients. Binary logistic regression analysis revealed that age (OR [95% CI] = 1.114 [0.991-1.251], P = 0.002), and Hcy level (OR [95% CI] = 0.931 [0.752-1.153], P = 0.411) were independent risk factors for V3 dilatation. Hcy level (OR [95% CI] = 0.557 [0.323-0.967], P = 0.035) were independent risk factors for MA atrophy. After adjustment for confounding factors, the odds ratio of V3 dilatation was 3.50 (95% CI 1.054-11.399, P = 0.031) and the odds ratio of MA atrophy was 4.67 (95% CI 1.395-15.602, P = 0.012) in the patients with higher Hcy level compared with the lower level. CONCLUSIONS: The results revealed a close association between the V3 width, MA and Hcy concentration in PD patients with cognitive impairment. We hypothesized that increased Hcy concentration played a significant role in the development of brain atrophy in PD with cognitive impairment.
Subject(s)
Cognition Disorders/etiology , Homocysteine/blood , Mesencephalon/pathology , Parkinson Disease/blood , Parkinson Disease/pathology , Third Ventricle/pathology , Aged , Aged, 80 and over , Atrophy , Case-Control Studies , Female , Humans , Male , Mesencephalon/diagnostic imaging , Middle Aged , Odds Ratio , Parkinson Disease/psychology , Risk Factors , Third Ventricle/diagnostic imaging , Ultrasonography, Doppler, TranscranialABSTRACT
BACKGROUND: Rigidity is one of the major manifestations of Parkinson's disease (PD), but no quantitative and objective imaging method has been developed to measure rigidity. Ultrasound shear wave elastography (SWE) can reflect the stiffness of tissue by providing a quantitative index. Thus, we conducted this study to evaluate the potential clinical value of SWE in assessing rigidity in PD. METHODS: A total of 63 subjects (44 patients with rigidity-dominant PD and 19 right-dominant-hand normal controls with matched age) were enrolled, and each underwent ultrasound SWE testing. The tests were conducted on the brachioradialis (BR) and biceps brachii (BB) on the more affected side in patients with PD and on the right side in normal controls. Differences in quantitative shear wave velocity (SWV) between patients with PD and normal controls were determined. The relationship of muscle SWV with joint rigidity, UPDRSIII, disease duration, sex, and age in patients with PD was analyzed. The intraclass correlation coefficient (ICC) was used to evaluate the reliability of SWE in assessing muscle stiffness in patients with PD. RESULTS: The mean SWVs of the BB and BR were higher in the PD group (3.65±0.46 and 4.62±0.89 m/s, respectively) than in normal controls (2.79±0.37 and 3.26±0.40 m/s, respectively). Stiffness in BR and BB was correlated with the upper-limb joint rigidity, UPDRSIII, and disease duration but not with sex or age in the PD group. The intraobserver correlation coefficients (ICCs) for interobserver and intraobserver variations in measuring SWV were 0.85 (95% confidence interval 0.56-0.95) and 0.85 (95% confidence interval 0.58-0.95), respectively, for BR and 0.90 (95% confidence interval 0.73-0.97) and 0.86 (95% confidence interval 0.61-0.95), respectively, for BB. CONCLUSIONS: SWV is associated with joint rigidity and disease duration, indicating that SWE can be potentially used as an objective and quantitative tool for evaluating rigidity.
Subject(s)
Elasticity Imaging Techniques , Parkinson Disease , Humans , Muscle, Skeletal/diagnostic imaging , Parkinson Disease/diagnostic imaging , Reproducibility of Results , Upper Extremity/diagnostic imagingABSTRACT
Orbital subperiosteal abscess (OSPA) secondary to paranasal sinus mucocele (PSM) is rare, and it may be misdiagnosed as PSM with orbital invasion or even as a malignant neoplasm. The present study explored the computed tomography (CT) and magnetic resonance imaging (MRI) features of OSPA. The cases of 13 patients with OSPA secondary to PSM were retrospectively reviewed. CT had been performed in 12, MRI in 7, and postcontrast MRI in 4. OSPA was revealed as a well-demarcated, spindle-shaped mass that was broad-based and located beneath the superior orbital wall (orbital roof) in 11 and at the medial wall in 2. PSM appeared as an expansile cystic lesion in the ethmofrontal sinus in 7, frontal sinus in 5, and ethmoidal sinus in 1. Because the OSPA was connected to the PSM, it looked like a single lesion involving both the orbit and the sinus. All 12 OSPAs examined on CT were low-density; 9 of the 12 PSMs were low-density and 3 were iso-density. Densities of the OSPAs and PSMs were equal in 4 and slightly different in 8. Five of the 10 OSPAs occurring beneath the orbital roof had unclear boundaries with the PSMs on CT. On MRI, although both OSPAs and PSMs mainly demonstrated hypointensity on T1-weighted images and hyperintensity on T2-weighted images, the signal intensities were slightly different, and linear-shaped hypointensity could be found between them. Postcontrast MRI revealed arch- and ring-shaped enhancement, respectively, at the edge of the OSPA and the PSM. Septal enhancement separated them more clearly. PSM is an important cause of OSPA in adults. CT and MRI can accurately display these entities' characteristic findings and their anatomic relationship, as well as playing an important role in the differential diagnosis.
Subject(s)
Abscess/diagnostic imaging , Bone Diseases/diagnostic imaging , Magnetic Resonance Imaging , Mucocele/complications , Paranasal Sinus Diseases/complications , Tomography, X-Ray Computed , Abscess/etiology , Adult , Aged , Aged, 80 and over , Bone Diseases/etiology , Ethmoid Sinus/diagnostic imaging , Female , Frontal Sinus/diagnostic imaging , Humans , Male , Middle Aged , Orbit/diagnostic imaging , Periosteum/diagnostic imaging , Retrospective Studies , Young AdultABSTRACT
The composite of poly-lactic-co-glycolic acid (PLGA) and calcium phosphate cements (CPC) are currently widely used in bone tissue engineering. However, the properties and biocompatibility of the alendronate-loaded PLGA/CPC (APC) porous scaffolds have not been characterized. APC scaffolds were prepared by a solid/oil/water emulsion solvent evaporation method. The morphology, porosity, and mechanical strength of the scaffolds were characterized. Bone marrow mesenchymal stem cells (BMSCs) from rabbit were cultured, expanded and seeded on the scaffolds, and the cell morphology, adhesion, proliferation, cell cycle and osteogenic differentiation of BMSCs were determined. The results showed that the APC scaffolds had a porosity of 67.43 ± 4.2% and pore size of 213 ± 95 µm. The compressive strength for APC was 5.79 ± 1.21 MPa, which was close to human cancellous bone. The scanning electron microscopy, cell counting kit-8 assay, flow cytometry and ALP activity revealed that the APC scaffolds had osteogenic potential on the BMSCs in vitro and exhibited excellent biocompatibility with engineered bone tissue. APC scaffolds exhibited excellent biocompatibility and osteogenesis potential and can potentially be used for bone tissue engineering.
Subject(s)
Alendronate/chemistry , Biocompatible Materials/chemistry , Bone Cements/chemistry , Calcium Phosphates/chemistry , Lactic Acid/chemistry , Polyglycolic Acid/chemistry , Animals , Bone and Bones/pathology , Cell Adhesion , Cell Cycle , Cell Differentiation , Cell Proliferation , Compressive Strength , Flow Cytometry , Male , Mesenchymal Stem Cells/cytology , Microscopy, Electron, Scanning , Microspheres , Osteogenesis/drug effects , Polylactic Acid-Polyglycolic Acid Copolymer , Porosity , Rabbits , Tissue Engineering/methods , Tissue ScaffoldsABSTRACT
BACKGROUND: Fetal unilateral lung agenesis, complicated with cardiac shifting, is a rare anomaly, the diagnosis of which remains a challenge for many sonographers in routine screening programs. The present study describes a systematic approach for the diagnosis of fetal unilateral lung agenesis and cardiac malpositions in routine prenatal screening. METHODS: A total of 18 cases of fetal unilateral lung agenesis complicated with cardiac malposition were reviewed. A systematic method was proposed to identify the fetal left side and right side according to the fetal head position and posture by acquiring a long axis and transverse view of the fetus. Fetal unilateral lung agenesis was diagnosed by evaluation of the ipsilateral pulmonary artery. The diagnosis was confirmed by postnatal echocardiography, digital radiology, and computed tomography after birth or by autopsy findings. RESULTS: The left-sided fetal heart with the cardiac apex rotating to the left and posterior were confirmed in all 7 left lung agenesis cases, while the rightward shifting of the fetal heart together with the cardiac axis deviating to the right were confirmed in all 11 cases of right lung agenesis. The disappearance of the ipsilateral pulmonary artery was confirmed in all 18 cases of unilateral lung agenesis. Cardiac anomalies were present in a total of 7 of the 18 cases of lung agenesis with 4 of 7 in cases of left lung agenesis and 3 of 11 in cases of right agenesis. CONCLUSIONS: The systematic approach introduced in the current report is helpful in the diagnosis of fetal unilateral lung agenesis complicated with cardiac malposition. The information provided by this study may be helpful to better understand unilateral lung agenesis anatomically and to facilitate its potential examination.