ABSTRACT
STUDY DESIGN: A prospective, anatomical imaging study of healthy volunteer subjects in accurate surgical positions. OBJECTIVE: To establish if there is a change in the position of the abdominal contents in the lateral decubitus (LD) versus prone position. SUMMARY OF BACKGROUND DATA: Lateral transpsoas lumbar interbody fusion (LLIF) in the LD position has been validated anatomically and for procedural safety, specifically in relation to visceral risks. Recently, LLIF with the patient in the prone position has been suggested as an alternative to LLIF in the LD position. MATERIALS AND METHODS: Subjects underwent magnetic resonance imaging of the lumbosacral region in the right LD position with the hips flexed and the prone position with the legs extended. Anatomical measurements were performed on axial magnetic resonance images at the L4-5 disc space. RESULTS: Thirty-four subjects were included. The distance from the skin to the lateral disc surface was 134.9 mm in prone compared with 118.7 mm in LD ( P <0.0001). The distance between the posterior aspect of the disc and the colon was 20.3 mm in the prone compared with 41.1 mm in LD ( P <0.0001). The colon migrated more posteriorly in relation to the anterior margin of the psoas in the prone compared with LD (21.7 vs . 5.5 mm, respectively; P <0.0001). 100% of subjects had posterior migration of the colon in the prone compared with the LD position, as measured by the distance from the quadratum lumborum to the colon (44.4 vs . 20.5 mm, respectively; P <0.001). CONCLUSION: There were profound changes in the position of visceral structures between the prone and LD patient positions in relation to the LLIF approach corridor. Compared with LD LLIF, the prone position results in a longer surgical corridor with a substantially smaller working window free of the colon, as evidenced by the significant and uniform posterior migration of the colon. Surgeons should be aware of the potential for increased visceral risks when performing LLIF in the prone position. LEVEL OF EVIDENCE: Level II-prospective anatomical cohort study.
Subject(s)
Intervertebral Disc , Spinal Fusion , Humans , Prospective Studies , Cohort Studies , Intervertebral Disc/surgery , Magnetic Resonance Imaging , Patient Positioning , Spinal Fusion/methods , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/surgery , Prone PositionABSTRACT
Few publications have compared ultrasound (US) to histology in diagnosing schistosomiasis-induced liver fibrosis (LF); none has used magnetic resonance (MR). The aim of this study was to evaluate schistosomal LF using these three methods. Fourteen patients with hepatosplenic schistosomiasis admitted to hospital for surgical treatment of variceal bleeding were investigated. They were submitted to upper digestive endoscopy, US, MR and wedge liver biopsy. The World Health Organization protocol for US in schistosomiasis was used. Hepatic fibrosis was classified as absent, slight, moderate or intense. Histology and MR confirmed Symmers' fibrosis in all cases. US failed to detect it in one patient. Moderate agreement was found comparing US to MR; poor agreement was found when US or MR were compared to histology. Re-classifying LF as only slight or intense created moderate agreement between imaging techniques and histology. Histomorphometry did not separate slight from intense LF. Two patients with advanced hepatosplenic schistosomiasis presented slight LF. Our data suggest that the presence of the characteristic periportal fibrosis, diagnosed by US, MR or histology, associated with a sign of portal hypertension, defines the severity of the disease. We conclude that imaging techniques are reliable to define the presence of LF but fail in grading its intensity.
Subject(s)
Liver Cirrhosis , Liver Diseases, Parasitic , Schistosomiasis mansoni , Splenic Diseases , Adult , Biopsy , Esophageal and Gastric Varices/etiology , Esophageal and Gastric Varices/surgery , Female , Humans , Liver Cirrhosis/diagnostic imaging , Liver Cirrhosis/parasitology , Liver Cirrhosis/pathology , Liver Diseases, Parasitic/diagnostic imaging , Liver Diseases, Parasitic/etiology , Liver Diseases, Parasitic/pathology , Male , Middle Aged , Schistosomiasis mansoni/complications , Schistosomiasis mansoni/diagnostic imaging , Schistosomiasis mansoni/pathology , Severity of Illness Index , Splenectomy , Splenic Diseases/diagnostic imaging , Splenic Diseases/parasitology , Splenic Diseases/pathology , Ultrasonography , Young AdultABSTRACT
For the last two decades, ultrasound (US) has been considered a surrogate for the gold standard in the evaluation of liver fibrosis in schistosomiasis. The use of magnetic resonance imaging (MRI) is not yet standardised for diagnosing and grading liver schistosomal fibrosis. The aim of this paper was to analyse MRI using an adaptation of World Health Organization (WHO) patterns for US assessment of schistosomiasis-related morbidity. US and MRI were independently performed in 60 patients (42.1 +/- 13.4 years old), including 37 men and 23 women with schistosomiasis. Liver involvement appraised by US and MRI was classified according to the WHO protocol from patterns A-F. Agreement between image methods was evaluated by kappa index (k). The correlation between US and MRI was poor using WHO patterns [k = 0.14; confidence interval (CI) 0.02; 0.26]. Even after grouping image patterns as "A-D", "Dc-E" and "Ec-F", the correlation between US and MRI remained weak (k = 0.39; CI 0.21; 0.58). The magnetic resonance adaptation used in our study did not confirm US classification of WHO patterns for liver fibrosis.
Subject(s)
Liver Cirrhosis/diagnostic imaging , Liver Cirrhosis/pathology , Liver Diseases, Parasitic/diagnostic imaging , Liver Diseases, Parasitic/pathology , Schistosomiasis mansoni/diagnostic imaging , Schistosomiasis mansoni/pathology , Adolescent , Adult , Aged , Female , Humans , Liver Cirrhosis/parasitology , Magnetic Resonance Imaging , Male , Middle Aged , Schistosomiasis mansoni/complications , Severity of Illness Index , Ultrasonography , World Health Organization , Young AdultABSTRACT
Few publications have compared ultrasound (US) to histology in diagnosing schistosomiasis-induced liver fibrosis (LF); none has used magnetic resonance (MR). The aim of this study was to evaluate schistosomal LF using these three methods. Fourteen patients with hepatosplenic schistosomiasis admitted to hospital for surgical treatment of variceal bleeding were investigated. They were submitted to upper digestive endoscopy, US, MR and wedge liver biopsy. The World Health Organization protocol for US in schistosomiasis was used. Hepatic fibrosis was classified as absent, slight, moderate or intense. Histology and MR confirmed Symmers' fibrosis in all cases. US failed to detect it in one patient. Moderate agreement was found comparing US to MR; poor agreement was found when US or MR were compared to histology. Re-classifying LF as only slight or intense created moderate agreement between imaging techniques and histology. Histomorphometry did not separate slight from intense LF. Two patients with advanced hepatosplenic schistosomiasis presented slight LF. Our data suggest that the presence of the characteristic periportal fibrosis, diagnosed by US, MR or histology, associated with a sign of portal hypertension, defines the severity of the disease. We conclude that imaging techniques are reliable to define the presence of LF but fail in grading its intensity.
Subject(s)
Adult , Female , Humans , Male , Middle Aged , Young Adult , Liver Cirrhosis , Liver Diseases, Parasitic , Schistosomiasis mansoni , Splenic Diseases , Biopsy , Esophageal and Gastric Varices , Esophageal and Gastric Varices , Liver Cirrhosis , Liver Cirrhosis/pathology , Liver Cirrhosis , Liver Diseases, Parasitic , Liver Diseases, Parasitic/pathology , Liver Diseases, Parasitic , Severity of Illness Index , Splenectomy , Schistosomiasis mansoni , Schistosomiasis mansoni/pathology , Schistosomiasis mansoni , Splenic Diseases , Splenic Diseases/pathology , Splenic DiseasesABSTRACT
For the last two decades, ultrasound (US) has been considered a surrogate for the gold standard in the evaluation of liver fibrosis in schistosomiasis. The use of magnetic resonance imaging (MRI) is not yet standardised for diagnosing and grading liver schistosomal fibrosis. The aim of this paper was to analyse MRI using an adaptation of World Health Organization (WHO) patterns for US assessment of schistosomiasis-related morbidity. US and MRI were independently performed in 60 patients (42.1 ± 13.4 years old), including 37 men and 23 women with schistosomiasis. Liver involvement appraised by US and MRI was classified according to the WHO protocol from patterns A-F. Agreement between image methods was evaluated by kappa index (k). The correlation between US and MRI was poor using WHO patterns [k = 0.14; confidence interval (CI) 0.02; 0.26]. Even after grouping image patterns as "A-D", "Dc-E" and "Ec-F", the correlation between US and MRI remained weak (k = 0.39; CI 0.21; 0.58). The magnetic resonance adaptation used in our study did not confirm US classification of WHO patterns for liver fibrosis.
Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Liver Cirrhosis/pathology , Liver Cirrhosis , Liver Diseases, Parasitic/pathology , Liver Diseases, Parasitic , Schistosomiasis mansoni/pathology , Schistosomiasis mansoni , Liver Cirrhosis , Magnetic Resonance Imaging , Severity of Illness Index , Schistosomiasis mansoni , World Health OrganizationABSTRACT
Abdominal ultrasound (US) has been widely used in the evaluation of patients with schistosomiasis mansoni. It represents an important indirect method of diagnosis and classification of the disease, and it has also been used as a tool in the evaluation of therapeutic response and regression of fibrosis. We describe the case of a man in whom US showed solid evidence of schistosomal periportal fibrosis and magnetic resonance imaging revealed that periportal signal alteration corresponded to adipose tissue which entered the liver togheter with the portal vein.
Subject(s)
Animals , Humans , Male , Middle Aged , Liver Cirrhosis , Liver Diseases, Parasitic , Portal Vein , Schistosomiasis mansoni , Liver Cirrhosis/parasitology , Liver Cirrhosis/pathology , Liver Cirrhosis , Liver Diseases, Parasitic/parasitology , Liver Diseases, Parasitic/pathology , Liver Diseases, Parasitic , Magnetic Resonance Imaging , Portal Vein/parasitology , Portal Vein/pathology , Portal Vein , Severity of Illness Index , Schistosomiasis mansoni/complications , Schistosomiasis mansoni/pathology , Schistosomiasis mansoniABSTRACT
Abdominal ultrasound (US) has been widely used in the evaluation of patients with schistosomiasis mansoni. It represents an important indirect method of diagnosis and classification of the disease, and it has also been used as a tool in the evaluation of therapeutic response and regression of fibrosis. We describe the case of a man in whom US showed solid evidence of schistosomal periportal fibrosis and magnetic resonance imaging revealed that periportal signal alteration corresponded to adipose tissue which entered the liver together with the portal vein.