Conventional computed tomography software can be used for accurate pre-operative templating in bipolar hip arthroplasty: A preliminary report

BackgroundThe aim of this study was to investigate the use of pre-operative templating for bipolar hip arthroplasty (BHA) for displaced femoral neck fracture using multiplanar reconstruction (MPR) of computed tomography (CT) images.MethodsNineteen patients who underwent BHA were enrolled in this study. For pre- and post-operative evaluation, a CT scan was performed from the pelvis to the knee joints. MPR of the CT image was done using software to measure the femoral head cup diameter, offset, stem size, length of the modular neck, distance from the neck osteotomy, and femoral anteversion. We compared these parameters pre- and post-operatively.ResultsBoth the femoral head cup diameter and length of the modular neck were found to be significantly different between pre- and post-operative measurements, although the differences were minor. Other parameters, including the femoral offset, were not significantly different between the pre- and post-operative measurements. The size of the femoral stem, cup diameter, and length of the modular neck were consistent with the planned size and accurate (within ±1 size) in more than 84% cases.ConclusionOur pre-operative templating approach for BHA using MPR of CT has potential clinical utility as a complementary tool for pre-operative planning using three-dimensional templating software. Moreover, this technique could be feasible in most hospitals without additional expenditure.     

Use of computed tomographic reconstruction to establish the ideal entry point for pedicle screws in idiopathic scoliosis

Objective  

To determine the ideal entry point for individual pedicle screw in the surgical treatment of idiopathic scoliosis using computed tomographic (CT) three-dimensional (3D) reconstruction.     

Computed tomography with multiplanar reformation and three-dimensional image reconstruction in the preoperative evaluation of adult hip disease

Summary Computed tomography (CT) with multiplanar reformation and three-dimensional (3D) image reconstruction was used pre-operatively to outline the bony morphological changes and femoral-acetabular relationships in 25 adult patients suffering from hip disease. Diagnoses included ischaemic necrosis of the femoral head, osteoarthritis, rheumatoid arthritis, calcium pyrophosphate dihydrate (CPPD) crystal deposition disease, previous trauma and chronic dislocation. Polyethylene models of the femora and acetabula were constructed from three-dimensional contouring of CT data and compared with resected specimens in patients subjected to subsequent total hip arthroplasty. Information provided by this imaging technique was useful in both selecting and guiding the most appropriate surgical procedure and it was found that models depicted the actual bony contours with reasonable accuracy. CT combined with multiplanar reformation and 3D analysis may be the optimal pre-operative means of assessment of the diseased adult hip.

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Résumé La tomodensitométrie (TDM) avec reconstruction multiple et tri-dimensionnelle (3 D) des images a été utilisée avant l'intervention afin de visualiser les modifications de la morphologie osseuse et les rapports entre le cotyle et la tête du fémur chez 25 sujets adultes présentant une hanche pathologique. Les diagnostics étaient nécrose de la tête fémorale, arthrose, arthrite rhumatoïde, chondrocalcinose, séquelles de traumatismes et de luxation congénitale. Des modèles en polyéthylène du fémur et du cotyle ont été réalisés à partir des données tri-dimensionnelles fournies par la TDM et comparées avec les pièces opératoires réséquées chez les patients traités par arthroplastie totale. Les informations apportées par cette technique d'imagerie ont été utiles à la fois pour indiquer et effectuer le meilleur procédé opératoire et on a trouvé que les modèles représentaient les véritables contours osseux avec une précision satisfaisante. La TDM avec reconstruction multiple et tri-dimensionnelle (3 D) pourrait être le meilleur moyen pré-opératoire d'évaluation d'une hanche pathologique chez l'adulte.

     

Anatomic analysis of computed tomography images obtained during fluoroscopic computed tomography-guided percutaneous lumbar sympathectomy

Purpose  The fluoroscopic computed tomography (CT)-guidance technique increases the accuracy and safety of needle placement for percutaneous lumbar sympathectomy. The aim of the present study was to provide anatomic data from CT images and to discuss the safest route for needle insertion. Methods  We retrospectively analyzed CT images that were obtained from 25 patients (14 men, 11 women; 37—89 years of age [mean, 68.4 years]) during fluoroscopic CT-guided percutaneous lumbar sympathectomy. The anatomy around the inserted needle was measured and the correlations between patient characteristics and the procedure-related distances were assessed. Results  The distance from the midline (spinous process) to the entry point and the depth to the target site correlated with body size, especially height and weight. The maximal distance from midline to the insertion point in the range of safe needle insertion at L2 was less than 7.0 cm in approximately 20% of the patients. Conclusion  The present study was performed to determine the anatomic details required to guide safe percutaneous lumbar sympathectomy based on CT images. The use of CT guidance is recommended for lumbar sympathectomy, especially at the L2 spinal level.     

The diagnostic value of computed tomography in orbital diseases

Summary Computed tomography (CT) has given us a new method for examining the orbit and its contents. The indications for the application of computed tomography in ophthalmology are considered: suspected orbital tumors, unilateral exophthalmos, pareses of the ocular muscles, traumatic lesions and malformations in the region of the orbit. The findings in 520 cases of orbital lesions examined in this study are reported and the differential diagnosis is discussed. Considerable improvement and greater accuracy in diagnosis have been achieved in the field of ophthalmology by using computed tomography. Early tumor visualization is possible without risk or discomfort to the patient.Dedicated to Professor K. J. Zülch on the occasion of his 70th birthday.     

Communicating spinal arachnoid cysts: diagnosis by delayed metrizamide computed tomography

A case of an extradural spinal arachnoid cyst is presented with emphasis on the neuroradiologic characteristics of this lesion. The cyst was definitely diagnosed by delayed metrizamide spinal computed tomography. Extradural spinal arachnoid cysts, or diverticula, have been the subject of much discussion in the neuroradiologic and neurosurgical literature. However, the appearance of a communicating arachnoid cyst on delayed spinal computed tomography after metrizamide myelography is heretofore undescribed in the English language neurosurgical literature.     

Evaluation of peritalar subluxation in adult acquired flatfoot deformity using computed tomography and weightbearing multiplanar imaging

Background

The aim of this study was to assess the inferior talus-superior talus (inf-tal-sup-tal) angle (previously proven reliable in multiplanar-weight bearing imaging (MP-WB)) on both computed tomography (CT) and MP-WB scans. We sought to compare the angle between the two modalities in both AAFD and control groups, as well as to compare the groups to each other.

Anatomical considerations for cervical pedicle screw insertion: the use of multiplanar computerized tomography measurements in 122 consecutive clinical cases

Background contextSuccessful placement of pedicle screws in the cervical spine requires a sufficient three-dimensional understanding of pedicle morphology to allow accurate identification of the screw axis.PurposeThe goal of the present study was to assess morphologic trends from one level to the next with respect to linear and angular parameters associated with the subaxial cervical pedicles.Study design/settingWe evaluated the pedicle morphology of cervical spine using axial and sagittal computed tomography (CT) imaging. The C3–C7 vertebrae in 122 patients (610 vertebrae) were evaluated (age range, 14–93; mean, 48 years).MethodsThin cut (2.5 mm thickness) axial CT images were measured. Sagittal reconstructions were obtained using 1.25-mm thickness slices. The following pedicle parameters were assessed: pedicle width (PW, the mediolateral diameter of the pedicle isthmus, perpendicular to the pedicle axis), pedicle height (PH, rostro-caudal dimension of the pedicle determined on the sagittal image), maximal screw length (MSL, distance from the posterior cortex of the lateral mass to the anterior wall of the vertebral body along the pedicle axis), and pedicle transverse angle (PTA, angle between the pedicle axis and the midline vertebral body).ResultsThe overall mean PW and PH ranged from 4.7 to 6.5 mm and 6.4 to 7.0 mm, respectively. For both these parameters there was a trend toward increasing size proceeding caudally in the cervical spine. The mean PW and PH was greater in males than in females, and this difference was statistically significant at all levels (p<.0001). The overall mean MSL ranged from 29.9 to 32.9 mm. All intersections of the pedicle axis and the posterior cortex of the lateral mass were located at the most lateral portion of the lateral mass for the C3–C6 vertebrae. The overall mean PTA ranged from 37.8° to 45.3°. The overall mean PTA was approximately 44° from C3 to C6 and 37.8° at C7.ConclusionThe findings of our radiological anatomical study suggest that the preoperative CT scans of patients undergoing cervical transpedicular fixation should be thoroughly analyzed and close attention paid to the pedicle size and its angulation. The placement of cervical pedicle screws should be individualized for each patient and based on detailed preoperative planning.     

脊柱去松质骨截骨治疗僵硬性脊柱侧凸的有效性及安全性分析

目的 探讨脊柱去松质骨截骨(VCD)治疗僵硬性脊柱侧凸畸形的有效性及安全性.方法 回顾性分析2004年5月至2008年2月实施VCD的32例僵硬性脊柱侧凸畸形患者的临床资料.其中男性12例,女性20例;平均年龄18岁(10～56岁).手术技术包括多节段VCD,切除顶椎区域残留椎间盘,对脊柱侧凸畸形进行矫形并后路椎弓根钉内固定.随访时除行常规X线片检查外,部分病例采用CT三维重建技术对截骨部位融合情况进行评估.通过术前术后X线片对矫形效果进行评价,并对术中、术后并发症情况进行统计分析.结果 本组平均切除2.1个椎体,平均固定融合10.6个节段(范围:8～13个节段).平均手术时间270 min(215～380 min).术中平均出血1560 ml(范围:900～4800 ml).4例患者出现手术并发症,其中出现一过性神经症状2例,脑脊液漏1例,硬膜外血肿1例.患者均获随访,随访时间24～48个月,平均31个月.术前冠状面Cobb角92°～138°,平均108°,术后矫正至32°～51°,平均42°;平均矫正率为61%.矢状面Cobb角术前平均82.0°,术后矫正至28.7°.所有患者截骨部位获得坚固融合,没有发现断钉断棒及内固定松动等并发症.结论 单纯后路VCD治疗僵硬性脊柱侧凸畸形安全有效.     

胸椎椎弓根螺钉置入位置的CT评价

目的:探讨胸椎椎弓根螺钉置入的准确性和安全性。方法:对37例胸椎椎弓根螺钉内固定患者术后行CT断层扫描,观察螺钉在椎弓根内的位置,记录螺钉穿透骨壁的位置、数目和距离。结果:37例患者共置入405枚胸椎椎弓根螺钉,124枚螺钉(30.61%)穿透骨壁,其中76枚(18.77%)穿透椎弓根外侧壁,32枚(7.90%)穿透椎弓根内侧壁,16枚(3.95%)穿透椎体前壁。66枚(16.30%)穿透距离<2mm,37枚(9.14%)穿透距离在2mm~4mm之间,21枚(5.9%)穿透距离>4mm。结论:胸椎椎弓根螺钉骨壁穿透率较高,应严格按照胸椎椎弓根螺钉置入方法,仔细操作,避免出现因螺钉置入不当造成神经、血管或内脏损伤等并发症。     

The measurement and designation of the pectus bar by computed tomography

Purpose

The length of the bar used for the Nuss procedure is typically determined by measuring the distance between the 2 midaxillary lines and subtracting 2.5 cm. However, this may not be accurate for all patients. Measurements of the chest using computed tomography (CT) were developed for better determination of bar length.

Methods

Seventy-five patients underwent the Nuss procedure between 2005 and 2008. The length and curve of the pectus bar were determined using both the traditional method (TM) and CT.

Results

Twelve patients (16%) had length differences (LD) with the methods. The LD and non-LD patients were 18.8 ± 2.4 and 11.3 ± 0.6 years old, respectively (P = .005). The proportion of females in the groups was 58.3% (7/12) and 28.6% (18/63), respectively (P = .046). The TM gave a longer bar estimation in all but one patient with a high sternal angulation. Slight bar protrusion was noted in 3 of the 12 patients with LD using TM and 0 of the 9 patients using CT.

Conclusions

Computed tomography measurement is a precise means for determining length, especially in older patients, females with developed breasts, or patients with high sternal angulation. It also allows for better curvature design, preventing multiple intraoperative adjustments.     

Determining the optimal surgical timing of fulminant Clostridium difficile colitis by using four objective factors and computed tomography findings: A case report

Introduction and importanceClostridium difficile colitis is increasingly seen in everyday clinical situations, and most cases are treated with antibiotics. Fulminant C. difficile colitis (FCDC) is rare; however, it is extremely virulent, and understanding its appropriate surgical treatment is critical. The surgical timing is controversial because of the lack of concrete decision-making factors. We report a case of FCDC with a favourable outcome, which was achieved by using four objective factors and computed tomography (CT) findings.Case presentationA patient with head trauma developed pneumonia at 2 days post-admission. He was prescribed with antibiotics. Fever and leucocytosis persisted on hospital day 10. Clostridium was detected in the stool on day 12, and metronidazole was administered. His condition did not improve; thus, he was started on vancomycin on day 14. The marked deterioration in the four laboratory parameters (white blood cell, albumin [Alb], creatinine, and body temperature) on day 15 and CT findings contributed to the decision to perform emergency subtotal colectomy and ileostomy. His condition improved dramatically postoperatively.Clinical discussionMany factors of FCDC are already suggested for surgical intervention in the guidelines; however, they are often seen at the late stage of FCDC. Early detection of FCDC is the key to favourable surgical outcome. Following the trend of these objective factors guides in making appropriate surgical decisions.ConclusionFocusing on the four objective factors and CT findings of FCDC could help surgeons detect FCDC at an early stage and decide the optimal surgical timing.     

Acute cholecystitis in the elderly: use of computed tomography and correlation with ultrasonography

Background

Elderly patients diagnosed with acute cholecystitis (AC) may undergo both ultrasonography (US) and computed tomography (CT).

Methods

A total of 475 patients (age, >64 y) with AC were included.

Results

Groups included US alone (n = 240), CT alone (n = 60), and CT + US (n = 168). Sixty patients (35.7%) in the US + CT group had inflammation in both studies, 34 (20.2%) had inflammation only on US, and 32 (19.0%) had inflammation only on CT. In the US + CT group, detection of cholelithiasis was not different, but mean common bile duct size did not correlate. There was no difference among the groups in age, sex, medical service admission, nonambulatory status, dementia, diabetes, or coronary artery disease. Peritonitis, leukocytosis, and acidosis were more frequent in the 2 groups undergoing CT. The cholecystectomy rate was lowest (and the complication rate was highest) in the CT + US group.

Conclusions

CT often is used in the diagnosis of AC in the elderly, especially those with more acute presentations. CT and US findings may be complementary in AC.     

Determinants of vagina by computed tomography in Korean women

Introduction and hypothesis  The purpose of this study was to determine the interrelations of the total vaginal length (TVL), total vaginal thickness (TVT), and total vaginal width (TVW), as measured by CT, and age, height, weight, and mode of delivery in Korean women. Methods  One hundred eighty-five women were evaluated by between 2006 and 2008. To assure objectivity, two doctors measured the TVL, TVT, and TVW twice in the CT sagittal view. Results  When the women were stratified into age groups, there were no statistical differences in TVL and TVT, but there was a meaningful statistical difference in TVW. Parity did not have a statistically significant effect on the TVL and TVT; however, the TVW in the NSD group was significantly greater than that in the C-sec group. Conclusions  Parity, age, height, and weight are not associated with differences in baseline dimensions of the vagina, but the TVW is related to age and mode of delivery in Korea women.     

胰腺导管内乳头状黏液瘤的CT诊断

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a rare tumor which has malignant potential.Differentiating IPMN from other cystic lesions of the pancreas is difficult. Its clinical sy...     

Accuracy of computed tomography in predicting appendiceal perforation

Background

Some surgeons use nonoperative management with or without interval appendectomy for patients who present with perforated appendicitis. These strategies depend on accurately delineating perforation by computed tomography (CT). Since 2005, our institution has used an evidence-based definition for perforation as a hole in the appendix or fecalith in the abdomen. This has been shown to clearly separate those with a high risk of abscess from those without. To quantify the ability of CT to identify which patients would meet these criteria for perforation, we tested 6 surgeons and 2 radiologists who evaluated blinded CT scans.

Methods

A junior and senior surgical residents, 2 staff interventional radiologists, and 4 attending pediatric surgeons with 3 to 30 years of experience reviewed 200 CT scans of pediatric patients who had undergone a laparoscopic appendectomy. All CT scans were reviewed electronically, and the reviewers were blinded to the results, outcome, and intraoperative findings. None of the patients had a well-formed abscess on CT. The reviewers were asked to decide only on perforated or nonperforated appendicitis according to our intraoperative definition. Clinical admission data were reviewed and compared between groups.

Results

In total, the reviewers were correct 72% of the time with an overall sensitivity of 62% and a specificity of 81%. The overall positive predictive value was 67%, and the negative predictive value was 77%.

Conclusions

This study shows that in the absence of a well-formed abscess, the triage of patient care based on a preoperative diagnosis of perforation from CT may be imprudent and subject a portion of the population to an unnecessarily prolonged course of care.