Three-dimensional Volume-rendered Images Research Articles

A Study of Arterial Supply to Carotid Body Tumor and Its Prospective Implication in Clinical Practice

Introduction and Objectives: Arterial supply to carotid body tumor is primarily from ascending pharyngeal artery (APA), a branch of the external carotid artery, and with infrequent feeders from other branches of the latter described in the literature. The present study attempted in describing other sources of arterial supply to carotid body tumor and its implication in clinical practice. Materials and Methods: This study was retrospective to start with turning a prospective midway for 5 years from July 2017 to July 2022. The data of all the 12 patients, in whom seven males and five females with a mean average of 45 years, were analyzed, There were seven males and five females with the mean age of 45 years; the average size of the tumor documented was 5 cm. All the patients underwent computed tomography angiography for confirming the diagnosis. Three-dimensional volume-rendered images from the rotational angiogram were analyzed for assessing the arterial supply. All patients underwent surgical excision without embolization. Results: In all 12 patients, APA was found primarily the main source of blood supply. Four patients, in addition, had occipital artery and superior thyroid in one. Two patients were identified to have glomic artery arising from the bulb of the common carotid artery supplying the tumor. The thyrocervical trunk was also supplying the tumor in a patient. Anomalous branches from the internal carotid artery were found to be the sole source of arterial supply to the tumor in a patient. Conclusion: Surgical excision of carotid body tumors still continues to be a challenge due to multiple arterial feeders leading to hypervascularity. A detailed knowledge of arterial supply helps in proper planning and reducing perioperative bleeding. The glomic artery, and in rare cases, the internal carotid artery, also contribute as a feeder to the tumor. These unusual arterial feeders give an important warning before routine embolization to avoid cerebrovascular events.

Postmortem radiological imaging and autopsy of a manually strangled dog with a neck twist

• Tracheal rupture with ischemic stroke was documented in a dog abuse case. • Excessive gas buildup caused by an air hunger effect was discussed. • PMCT was more appropriate to study the subtle bone structures to diagnose fractures. • Radiological imaging assists in determining a cause and manner of death in prosecuting animal crime. Forensic imaging studies were used to supplement the postmortem examination of a poodle-type dog that died of an unknown cause in an animal crime investigation. The carcass was powdered and the neck was twisted to the left. At the death scene, the police felt crepitation while moving the carcass to the autopsy room. They wondered whether the ribs and cervical bones of the carcass had been broken. Conventional X-rays revealed air pockets along the trachea and also an abundance of air in the subcutaneous tissue and body cavities. Three-dimensional volume-rendered images created from postmortem computed tomography confirmed that the hyoid bone, cervical vertebrae, and ribs were all intact. The findings during the autopsy were focally extensive intradermal and intramuscular hemorrhages and bruises on the right side of the body, tracheal rupture, and substantial brain congestion and edema. The results of the imaging and autopsy findings referred to asphyxiation and hypoxic ischemic stroke in the manner of death caused by blunt force trauma to the neck. During the police inquiry, the accused confessed to strangling the dog with her bare hands.

Anatomical variations of cervical segment of internal carotid artery in patients with subarachnoid hemorrhage

The cervical segment of an internal carotid artery (cICA) usually has a straight vertical course without any branching. In the present study, variations of the cICA were evaluated based on the three-dimensional volume-rendered neurovascular images. The computed tomography angiography images of 56 patients diagnosed with subarachnoid hemorrhage (SAH) were evaluated retrospectively. Two separate researchers, blinded to each other and clinical information of the patients, evaluated the courses of cICA bilaterally. The variations were classified as tortuosity, kinking, and coiling. A total of 112 cICA segments of 56 patients were evaluated. The cICA variations were present in 21.4% of patients and 17.9% of segments. There was tortuosity in 5 (8.9%) patients, kinking in 4 (7.1%) patients, and coiling in 6 (10.7%) patients. Of 41 patients with aneurysmal SAH, there were a cICA variation in 8 (19.5%) patients. A cICA variation was detected in 4 (26.7%) of 15 patients with idiopathic SAH. The cICA variation ratio in SAH patients was concordant with studies performed in different patient groups. Although the ratio was slightly higher in idiopathic SAH patients, there was no statistical significance between the aneurysmal and idiopathic SAH groups. The coiling was more frequent in SAH patients compared to previous studies. The cICA variations tend to be bilateral in SAH patients.

Acute Limited Intimal Tear of the Right Aortic Sinus.

HomeRadiology: Cardiothoracic ImagingVol. 3, No. 6 Previous Images in Cardiothoracic ImagingFree AccessVascular ImagingAcute Limited Intimal Tear of the Right Aortic SinusLucas de Pádua Gomes de Farias , Márcio Campos Sampaio, José Honório de Almeida Palma da Fonseca, Luciana de Pádua Silva BaptistaLucas de Pádua Gomes de Farias , Márcio Campos Sampaio, José Honório de Almeida Palma da Fonseca, Luciana de Pádua Silva BaptistaAuthor AffiliationsFrom the UnitedHealth Group Brazil, Hospital Samaritano Paulista, Avenida Brigadeiro Luís Antônio 1895, Bela Vista, São Paulo, SP 01317-002, Brazil.Address correspondence to L.d.P.G.d.F. (e-mail: [email protected]).Lucas de Pádua Gomes de Farias Márcio Campos SampaioJosé Honório de Almeida Palma da FonsecaLuciana de Pádua Silva BaptistaPublished Online:Dec 2 2021https://doi.org/10.1148/ryct.210239MoreSectionsPDF ToolsImage ViewerAdd to favoritesCiteTrack CitationsPermissionsReprints ShareShare onFacebookTwitterLinked In Limited intimal tears (LITs) are uncommon but potentially lethal lesions within the dissection spectrum, occurring in approximately 5% of patients presenting with acute aortic syndrome (1). LITs are classified as a “class 3 of intimal tear” and represented by intimomedial tears with an eccentric aortic wall bulge but without substantial hematoma (2). While the edges of an LIT can be undermined to a variable degree and filled with small amounts of blood or clot, there is no propagation of the dissection plane along the aorta and no exit tear and double-barrel flow channel as in classic aortic dissection (1,3). LITs may evade identification at transesophageal echocardiography or CT because of the limited extent of undermined intimal layers and a minimal amount of blood in the dissected aortic wall. This imaging pitfall can result in progression of dissection, cardiac tamponade, or aortic rupture causing potentially lethal outcomes (1,2,4). Furthermore, the diagnosis of LITs may be missed if conventional diagnostic criteria that are dependent on the presence of an intimal flap are applied (4). Awareness of this entity, high index of suspicion at CT angiography with use of appropriate reconstruction techniques for the aortic root may allow timely patient management (1) (Figure).Images in a 62-year-old man who presented to the emergency department with acute chest pain. (A) Short-axis view of the aortic root, (B) three-chamber view, (C–E) three-dimensional volume-rendered images, and (F) intraoperative view after median sternotomy with extracorporeal circulation show an eccentric bulge of the right aortic sinus (R) with the presence of a focal limited tear (arrowhead). This is represented by focal linear “flaps” with undermined edges, as a bandlike outpouching where the right coronary artery (RCA) took off. The patient underwent graft replacement of the ascending aorta and aortic valve replacement. AA = ascending aorta, LA = left atrium, LV = left ventricle, LM = left main artery, R/L/NC = right/left/noncoronary aortic sinus.Download as PowerPointOpen in Image Viewer Disclosures of conflicts of interest: L.d.P.G.d.F. No relevant relationships. M.C.S. No relevant relationships. J.H.d.A.P.d.F. No relevant relationships. L.d.P.S.B. No relevant relationships.Keywords: CT Angiography, Vascular, Aortic RootAuthors declared no funding for this work.

Three-dimensional volume-rendered computed tomography application for follow-up fracture healing and volume measurements pre-surgical rib fixation and post-surgical rib fixation.

Surgical rib fixation (SRF) is being used increasingly in trauma centers for stabilization of chest wall injuries, in line with new and evolving surgical techniques. Our institution has developed a pathway for the management of chest wall injuries and SRF, which includes a follow-up low-volume, noncontrast computed tomography (CT) scan at 12 months. This study was a single-center retrospective study conducted on 25 consecutive patients who underwent SRF between February 2019 and February 2020. All CT measurements were done by a CT radiographer under the supervision of a board-certified radiologist and included the use of three-dimensional volume-rendered images. There were no patients with SRF who experienced hardware failure at 12 months in either flail or nonflail groups. For fractured ribs treated with SRF, complete or partial union occurred in 75 of 76 ribs plated (98.7%). The median ratio for improvement in lung volumes was 1.71 for flail SRF and 1.69 for nonflail SRF in our study. Three-dimensional volume-rendered CT at 12 months post-SRF showed good alignment (no hardware failure) and fracture healing of fixed ribs in both flail and nonflail groups. Lung volumes also improved pre-SRF and post-SRF for both flail and nonflail patients. More studies are needed to define how the pattern of rib fracture healing of fixed and nonfixed ribs affects lung volumes. Therapeutic, Level V.

Understanding the Aorta-Spine Relation in Idiopathic Scoliosis: Value of Noncontrast CT-Derived Curved Coronal Reformats and 3D Volume Images.

Investigating axial position and longitudinal bending of the aorta in relation to spine curvature in adolescent idiopathic scoliosis patients could help surgeons in planning of spine surgeries. Noncontrast computed tomography (CT) scans of 27 consecutive patients with adolescent idiopathic scoliosis (19 right and 8 left curves) and 16 control subjects were retrospectively reviewed. Using semiautomated software, centerline was drawn along the descending aorta, and curved reformat was generated. Aorta tortuosity index (TI) was calculated as (centerline length/straight line distance) - 1 × 100. The spine centerline was drawn from T1 to L5, and curve index (CI) was similarly calculated. The aorta centerline angle was measured. Apical vertebral-rotation angle and multilevel aorto-vertebral angles were measured on axial CT. Three-dimensional volume-rendered images of the aorta were generated using a manual region grow function. Mean (± standard deviation) Cobb's angle was 63.8 ± 34.6°. The spine CI of patients (9.7 ± 7.11) was significantly higher than controls (0.28 ± 0.22), P = .00001. Aorta TI in scoliosis was significantly higher than controls (6.4 ± 7.2 versus 0.6 ± 0.5, P = .0001). The aorta centerline angle was steeper in scoliosis than controls (140 ± 26.8° versus 170 ± 3.6°). Correlations were excellent between the aorta TI and each of Cobb's angle, spine CI, and vertebral rotation angle (r = 0.851 to 0.867, all P < .001). Aorto-vertebral angles were significantly different between right scoliosis and left scoliosis patients and control groups at T6, T7, T8, L2, and L3 levels. Aortic curvature increases in proportion to the degree of scoliosis. The aorta follows the concavity of scoliosis in right and left curves. In the axial CT plane, the aorta in both right and left scoliosis is maximally rotated away from its normal position at T7 and is closest to its normal position at T11 to T12. Quantitative evaluation of aortic curvature combined with preoperative reconstructed CT images could be beneficial for surgeons in planning of spine surgeries.

Severe COVID-19 Pneumonia: Assessing Inflammation Burden with Volume-rendered Chest CT.

HomeRadiology: Cardiothoracic ImagingVol. 2, No. 2 PreviousNext Images in Cardiothoracic ImagingFree AccessPulmonary ImagingSevere COVID-19 Pneumonia: Assessing Inflammation Burden with Volume-rendered Chest CTLei Tang, Xiaoyong Zhang, Yvquan Wang, Xianchun Zeng Lei Tang, Xiaoyong Zhang, Yvquan Wang, Xianchun Zeng Author AffiliationsFrom the Department of Radiology, Guizhou Provincial People’s Hospital, Guiyang 550002, Guizhou Province, China.Address correspondence to X. Zeng (e-mail: [email protected]).Lei TangXiaoyong ZhangYvquan WangXianchun Zeng Published Online:Mar 6 2020https://doi.org/10.1148/ryct.2020200044MoreSectionsPDF ToolsImage ViewerAdd to favoritesCiteTrack CitationsPermissionsReprints ShareShare onFacebookTwitterLinked In COVID-19 (formerly known as 2019 novel coronavirus [2019-nCoV]) broke out in December 2019, and it spread from Wuhan, Hubei Province, to all over China and many other countries in the world (1–4). A 54-year-old woman with a travel history to Wuhan was admitted to the hospital with a 7-day history of fever (38.5°C [101.3°F]), cough, fatigue, and chest congestion. Laboratory examinations showed normal white blood cell count and lymphocytopenia, increased C-reactive protein level and erythrocyte sedimentation rate, and decreased CD3+, CD4+, CD8+, and CD4/CD8. Unenhanced chest CT revealed patchy peripheral ground-glass opacities with upper lobe predominance (Fig 1). A three-dimensional volume-rendering technique (PULMO 3D software, VB20; Siemens Healthineers, Forchheim, Germany) highlighted the distribution of pulmonary opacities, which was useful to determine the extension of the disease (Fig 2, Movie [supplement]). Her nasopharyngeal swab was positive for COVID-19 with real-time fluorescence polymerase chain reaction test. The patient was diagnosed with severe COVID-19 pneumonia. When treated with oxygen inhalation, moxifloxacin, lopinavir/ritonavir, umifenovir, interferon, and thymosin, her body temperature returned to normal and the symptoms slightly improved. CT reexamination on the 5th day of hospitalization indicated increased lesions and mild absorption on the 9th day.Figure 1: CT images in a 54-year-old woman with severe COVID-19 pneumonia. Transverse and coronal images reveal patchy peripheral ground-glass opacities with upper lobe predominance.Figure 1:Download as PowerPointOpen in Image Viewer Figure 2: CT images in a 54-year-old woman with severe COVID-19 pneumonia. A, The color coronal image highlights the distribution of lung lesions (red areas) because software is used to automatically segment and render. B, On a three-dimensional volume-rendering image, trachea, bronchus, lung tissues, and lesions are differentiated by CT values and automatically segmented.Figure 2:Download as PowerPointOpen in Image Viewer Get the Flash Player to see this video.Movie Three-dimensional volume-rendering movie in a 54-year-old woman with severe COVID-19 pneumonia. The images highlight the distribution of pulmonary lesions, which are useful to determine the extension of the inflammatory burden.Download Original Video (3.4 MB)Disclosures of Conflicts of Interest: L.T. disclosed no relevant relationships. X. Zhang disclosed no relevant relationships. Y.W. disclosed no relevant relationships. X. Zeng disclosed no relevant relationships.Keywords: CT, Computer Applications-3D, Infection, Lung Authors declared no funding for this work.

Use of Foramen Obturatum and Subpubic Angle in Sex Determination: Diagnostic Accuracy of Anthropometric Measurement on MDCT Images

Background: Sex determination from skeletal bones is very important, especially for forensic science and anthropology. Radiological techniques are commonly used for this purpose. Objectives: This study aimed to evaluate the accuracy rate of the subpubic angle and width-length ratio of foramen obturatum (FO) in sex determination and determine the cut-off values for differentiation between genders. Patients and Methods: Three-dimensional (3D) volume-rendered images were obtained from the pelvic CT scans of 100 patients (50 female, 50 male). The subpubic angle was automatically measured on these images using image analysis software. The maximum width and height of FO were recorded and their ratio were calculated. Results: The subpubic angle was between 75.9 and 101.2 in females (mean: 82.92 ± 15.06) and, 47.4 and 91.5 in males (mean: 67.91 ± 9.15). The accuracy rate of the subpubic angle in determining sex was 96%. For the best cut-off value of 79.45 on the subpubic angle, the parameters for sex determination were as follows: sensitivity 84%, specificity 74%, positive predictive value (PPV) 76%, and negative predictive value (NPV) 82%. The aspect ratio of FO was 0.48 - 0.74 (mean: 0.60 ± 0.039) for the right side and 0.48 - 0.72 (mean: 0.60 ± 0.054) for the left side in females, and 0.45 - 0.68 (mean: 0.55 ± 0.058) for the right side and 0.45 - 0.69 (mean: 0.54 ± 0.052) for the left side in males. For the best cut-off value of 0.615 on the right side, the parameters for sex determination were as follows: sensitivity 84%, specificity 74%, PPV 76%, and NPV 82%. The accuracy rate of the right-side FO in sex determination was 79%. For the best cut-off value of 0.635 on the left side, the parameters for sex determination were as follows: sensitivity 98%, specificity 32%, PPV 59%, and NPV 94%. The accuracy rate of the left-side FO in sex determination was 65%. Conclusions: The subpubic angle and aspect ratio of foramen obturatum parameters have high accuracy in determining sex.

Pelvic inlet shape measured by three-dimensional pelvimetry is a predictor of the operative time in the anterior resection of rectal cancer.

We evaluated pelvic shape as a predictor of the surgical outcome of anterior resection in patients with rectal cancer. In total, 228 patients who had undergone anterior resection (R0 resection and double-stapling anastomosis) for rectal cancer from 2005 to 2014 were included in this study. The anteroposterior (AP) and transverse (T) diameters of the pelvic inlet and outlet and pelvic depth were analyzed on three-dimensional volume-rendered images, and the AP/T ratio was calculated. Univariate and multivariate analyses were performed to determine the predictive significance of the operative time and intraoperative blood loss as surgical outcomes. No difference was observed between the inlet AP/T and patient sex ratios, but the other pelvic dimensions were significantly shorter in males than in females. The univariate analysis revealed that the operative time was significantly correlated with the inlet T diameter and that it tended to be correlated with the outlet T diameter and the inlet AP/T ratio. A multivariate analysis adjusted for operation-related factors revealed that the inlet AP/T ratio was the only independent risk factor for an extended operative time (p=0.036). None of the pelvic dimensions were independent risk factors for increased blood loss. The shape of the pelvic inlet may be useful for predicting the operative time.

Role of Multi-detector Computed Tomography in Medicolegal Evaluation of Non-Fatal Firearm Injuries in the Head in Assiut University Hospital

Background: Firearm injuries may cause physical disabilities, permanent infirmities, psychological harm or death of injured individuals. Multi-detector computed tomography (MDCT) became a mainstay noninvasive diagnostic tool in investigation of firearm injuries as it gives three dimensional imaging (3-D) and colored images. Objective: This study was designed to through light on the role of MDCT in medicolagal evaluation of non-fatal firearm injuries in the head which examined in Assiut University hospital. Subjects and Methods: this study was conducted on 67 cases of non-fatal firearm injuries in the head including an age group 16-70 years which presented in the trauma unit and outpatient clinic of neurosurgery department during the period from June 2013 to June 2015. After forensic examination, the cases were examined blindly by two consultant radiologists using 16-row multi-detector CT in diagnostic radiology department of Assiut University hospital after giving an informed consent. The obtained images were post-processed using an advanced diagnostic computer workstation to obtain multi-planar reformatted and three-dimensional volume-rendered images to examine soft tissues, skull and intracranial structures. The relevant disclosing MDCT images were documented, interpreted and data were discussed between participants of the research from departments of the forensic medicine and diagnostic radiology and compared to results of forensic examination. Statistical analysis of data was done. Results: Most of injuries occurred in males which represented 89.45% of total cases and the highest percentage of victims was in the age group 21-30 years which represented 31.3%. MDCT images help in determining details of inlets and exits (in soft tissue, bone and intracranial structures), recognizing the type of used firearm weapons (weapons firing shots represented 73.1%), retained projectiles, determination of the distance of firing (79.1 % of total). In addition it demonstrated retained projectiles which represented 46.3% of total cases and their details (types, numbers, shapes, sizes, trajectory and deflection inside the skull), intracranial hemorrhage, edema, skull fractures. It can help in determination of permanent infirmity (which represented 17.9% of total cases) and in planning for surgical interference. Conclusion: This study demonstrated that MDCT is an accurate diagnostic tool in the medicolegal investigations of firearm injuries. The MDCT images are documented forensic evidence which can be stored, electronically sent for medicolegal consultation and can be shown in the court. In addition, medicolegal experts can trust on MDCT for determination of permanent infirmities which can help injured persons to obtain compensations and determine responsibility of physicians about faults in malpractice claims.

Diagnostic accuracy of 3D color volume-rendered CT images for peroneal tendon dislocation in patients with acute calcaneal fractures

Use of three-dimensional (3D) color volume-rendered (VR) images has been reported to be more time-efficient compared to that of cross-sectional computed tomography (CT) images for the diagnosis of peroneal tendon dislocation. However, the diagnostic performance of this technique has not been studied. To test diagnostic accuracy of 3D color VR CT images of ankle for peroneal tendon dislocation in patients with acute calcaneal fractures. The study consisted of 121 ankle CT studies from 105 consecutive patients (85 men, 20 women; mean age, 42 years; age range, 16-75 years) with acute calcaneal fractures. Peroneal tendon dislocation was diagnosed on multiplanar CT images by consensus of two experienced musculoskeletal radiologists, which served as the reference standard. Three other musculoskeletal radiologists independently reviewed 3D images alone on a workstation. The readers determined whether or not there was peroneal tendon dislocation using three degrees of certainty (definite, probable, and possible). Diagnostic performance of 3D images for peroneal tendon dislocation was evaluated by calculating the sensitivities, specificities, and area under the receiver-operating characteristic (ROC) curves. Forty-eight (40%) out of 121 studies showed peroneal tendon dislocation based on the expert readings using multiplanar reformatted images. Sensitivities/specificities of 3D images measured 0.92/0.81, 0.88/0.90, and 0.81/0.92 for three readers, respectively. The area under the proper binormal ROC curve based on all three readers (0.93, 0.94, and 0.92) measured 0.93 with a 95% confidence interval of 0.89-0.98. Diagnostic accuracy of 3D images is comparable to, but not as good as that of MPR images for the diagnosis of peroneal tendon dislocation in patients with acute calcaneal fractures.

Preoperative evaluation of a subungual glomus tumor case using multidetector computed tomography angiography.

Dear Editor: Glomus tumors (GTs) are characterized by the triad of severe pain, pinpoint tenderness, and cold sensitivity. Most GTs are located in the fingertips, especially in the subungual region1,2. Ultrasonography and magnetic resonance imaging (MRI) are useful for preoperative diagnosis, and complete excision is usually recommended1,2,3,4,5. Although it is feasible to use multidetector computed tomography (MDCT) in the diagnosis of suspected vascular diseases, it has been not applied in subungual GT. Here, we describe a patient with a subungual GT that was identified using MDCT angiography. This study is approved by Affiliated Hospital of Guangdong Medical College (IRB No. PJ2012131). A 23-year-old woman presented with a 2-year history of severe pain in the thumb of the right hand on touch or exposure to cold. Physical examination revealed a 6×4-mm, purplish, flush with distal yellowish discoloration on the proximal nail plate of the right thumb (Fig. 1A). Palpation of the nail yielded excruciating pain. The patient was otherwise healthy and routine laboratory results were unremarkable. Ultrasonography revealed a 5.1×2.2-mm, hypervascular, hypoechogenic mass in the proximal nail bed of the right thumb. Fig. 1 Subungual glomus tumor on the distal part of the right thumb. (A) A 6×4-mm purplish flush (arrow) with distal yellowish discoloration on the right thumb. (B) No nail abnormality present at 4 months postoperation. The patient underwent 64-MDCT (Siemens Healthcare, Erlangen, Germany), and three-dimensional volume-rendered images were acquired on a workstation using 0.6-mm slice thickness and 0.4-mm interval. The scanned area ranged from the fingertips to the distal parts of the metacarpal bones of the right thumb. The contrast-enhanced scan was performed after pre-contrast scanning; image acquisition was begun after a delay of 30 s. The enhanced scanning showed a subungual nodule on the radial side of the right thumb and a depression of the distal phalanx. Volume-rendered reconstruction of bone images revealed a local depression in the distal phalanx of the right thumb, while vascular reconstruction enabled the visualization of a 4.5×3.5-mm subungual mass (Fig. 2) Fig. 2 Volume-rendered image of the vascular reconstruction displaying a hypervascularized nodule (arrow) overlying the distal phalanx of the right thumb. The patient underwent a transungual tumor resection with nail plate avulsion. A poorly demarcated reddish nodule was excised en bloc, followed by radiofrequency destruction. The nail bed wound healed through secondary wound closure. Pathological examination showed numerous small blood vessels surrounded by clusters of uniform cells. The cells were round with faintly eosinophilic cytoplasm and round nuclei. CD34 immunoreactivity was detected in both tumor and vascular endothelial cells, while α-smooth muscle actin was detected in the tumor cells. A diagnosis of subungual GT was made based on clinicopathologic clinicopathologic and immunohistochemical results. The patient had no nail abnormality at the 6-month follow-up (Fig. 1B). Since GT tumors are often only a few millimeters in size and the resection area is small, the surgical management of subungual GTs is challenging3. Ultrasound and MRI can display GTs as small as 2 mm in diameter1,4, but they are unable to achieve satisfactory bone imaging. Furthermore, it is difficult to display small and flattened subungual lesions with ultrasonography because the imaging results are often operator-dependent and the nail plate curvature may contribute to artifacts in the lateral nail folds4. In the presented case, repetitive ultrasonography showed a poorly demarcated hypoechogenic nodule, while MDCT angiography delineated a well-defined mass overlying a depression of the distal phalanx. Three-dimensional reconstruction can illustrate the tumor, vascular branches, and bony components in a single image. Therefore, although composite images of photography and ultrasonography can often identify the location and extent of subungual GTs5, MDCT angiography may be a more promising technique for an ill-defined tumor. In all, 5%~50% of postoperative recurrences are due to incomplete surgical removal of the tumor4. Because the tumor in the current case had ill-defined margins and a deep location, subsequent radiofrequency destruction was employed to prevent a possible recurrence.

Three-Dimensional Visualization of the Crack-Growth Behavior of Nano-Silver Joints During Shear Creep

Evolution of creep damage in nano-silver sintered lap shear joints was investigated at 325°C. Non-destructive x-ray three-dimensional (3D) visualization clearly revealed the crack-growth behavior of the joint; this could be divided into three stages. In the initial stage, little development of cracks occurred. In the second stage, cracks propagated at a consistent rate. In the final stage, rapid extension of the cracks led directly to fracture of the joint. Three-dimensional volume-rendered images and fractographic analysis showed that the growth of macroscopic initial cracks at the interfaces dominated the creep fracture process. Initial failure of nano-silver sintered lap shear joints often occurred at interfacial nano-silver paste layers. Both the size and position of the initial interfacial cracks had significant effects on the final creep failure of the joints, and higher stresses led to greater porosity and earlier failure.

Late aorto-left ventricular fistula following aortic valve replacement for infective endocarditis

Figure 2: Three-dimensional volume-rendering images from the computed tomography scan clearly demonstrate fistulous communication between the sinus of Valsalva and the abnormal cavity (arrow in A). The cavity was widely opened to the left ventricle (B). During the operation, a periannular slit-like fistula was found a small distance from the sewing ring of the prosthesis and closed with bovine pericardium, with reimplantation of the prosthetic valve. The patient’s symptoms resolved completely after surgery. Ao: ascending aorta; LA: left atrium; LV: left ventricle. Figure 1: Three-dimensional reconstructed image of an electrocardiographic-gated multislice computed tomography scan showing a large abnormal cavity (arrowheads) beside the sinus of Valsalva below the left coronary artery.

Quantitative analysis of factors affecting cobalt alloy clip artifacts in computed tomography.

ObjectiveClip artifacts limit the visualization of intracranial structures in CT scans from patients after aneurysmal clipping with cobalt alloy clips. This study is to analyze the parameters influencing the degree of clip artifacts.MethodsPostoperative CT scans of 60 patients with straight cobalt alloy-clipped aneurysms were analyzed for the maximal diameter of white artifacts and the angle and number of streak artifacts in axial images, and the maximal diameter of artifacts in three-dimensional (3-D) volume-rendered images. The correlation coefficient (CC) was determined between each clip artifact type and the clip blade length and clip orientation to the CT scan (angle a, lateral clip inclination in axial images; angle b, clip gradient to scan plane in lateral scout images).ResultsAngle b correlated negatively with white artifacts (r=-0.589, p<0.001) and positively with the angle (r=0.636, p<0.001) and number (r=0.505, p<0.001) of streak artifacts. Artifacts in 3-D images correlated with clip blade length (r=0.454, p=0.004). Multiple linear regression analysis revealed that angle b was the major parameter influencing white artifacts and the angle and number of streak artifacts in axial images (p<0.001), whereas clip blade length was a major factor in 3-D images (p=0.034).ConclusionUse of a clip orientation perpendicular to the scan gantry angle decreased the amount of white artifacts and allowed better visualization of the clip site.

Preprocedural coronary CT angiography significantly improves success rates of PCI for chronic total occlusion

Chronic total occlusions of coronary arteries occur in about 20% of patients with suspected coronary artery disease and are more frequent with increasing age. The success rate of interventions is lower (55-80%) compared to conventional lesions (>90%). Coronary CT angiography (coronary CTA) provides information about the occluded segment, which cannot be obtained from invasive angiograms (XA). We therefore hypothesized that preprocedural coronary CTA may improve success rates of percutaneous coronary intervention (PCI) for coronary arteries (CTO). 30 patients with chronic total coronary artery occlusions (mean age 73 years, 26 men) and predicted high complexity were imaged by coronary CTA prior to PCI for CTO. CT data sets were acquired with a 64 detector row dual source scanner and retrograde ECG gating, 0.6 mm collimation and z-flying focal spot, yielding isovoxel spatial resolution of about 0.4 mm. Based on the CT data sets, established complexity criteria for CTO (Euro CTO club, Di Mario et al. in EuroIntervention 3(1):30-43, 2007) were evaluated and compared to invasive coronary angiography. Three-dimensional volume-rendered images of the occluded coronary artery were displayed in the catheterization lab during PCI to guide the advancement of the wire. PCI success, defined as the ability to advance the guide wire into the distal lumen with thrombolysis in myocardial infarction III flow was compared to 43 controls without coronary CTA using propensity score matching based on established criteria of procedural success. The course of the occluded segments was visualized by coronary CTA in all cases. Calcification, lesion length, stump morphology and presence of side branches were underestimated by invasive angiograms when compared to coronary CTA. PCI success rate in 30 patients who underwent pre-procedural CTA was significantly higher than in patients without prior coronary CTA [unmatched: CT 90% (27/30) vs. no CT 63% (27/43), p = 0.009; matched: CT 88% (22/25) vs. no CT 64% (16/25) p = 0.03]. Through information not readily seen on invasive coronary angiography, coronary CTA can significantly enhance success rates of PCI for CTO.

Bilateral Inguinal Hernia with Uncommon Content

Ataturk University, Erzurum, Turkey Correspondence: Dr Hayri Ogul, Ataturk University, Erzurum 25240, Turkey. Telephone 90-442-2316751, e-mail drhogul@gmail.com Received for publication September 16, 2012. Accepted September 20, 2012 Case presentation A 56-year-old man was admitted to hospital with recurrent vomiting, left lower quadrant pain and bulges in both the left and right groin. The axial computed tomography (CT) scan (Figure 1) and threedimensional volume-rendering images (Figure 2) showed the antrum descended in the left inguinal canal together with a large amount of omental fat and small intestine, and herniation of the bladder toward the right inguinal canals.

Assessment of ureteric obstruction with 16-MDCT: Curved planar reformats versus three-dimensional volume-rendered images and their corresponding maximum intensity projections

AimTo compare the sensitivity and diagnostic accuracy of curved planar reformation (CPR) image on the one hand versus combined volume-rendered (VR) image and its corresponding maximum intensity projection (MIP) image on the other hand for determination of the cause and level of ureteral obstruction. Materials and methodsThe study included 60 patients with clinical and sonographic manifestations of ureteral obstruction who underwent two-phase multidetector CT urography (MDCTU) using a 16-slice machine. A total of 82 ureters were examined. CPR images were performed to display the entire course of ureters in the same image. 3D VR reformats and their corresponding MIP were used to enhance visualization of opacified ureters. The sensitivity and accuracy of CPR, and combined 3D VR and MIP for diagnosis of ureteral obstruction were calculated and compared in reference to the gold standard. ResultsThe cause of ureteral obstruction was calculous in 28/82 ureters (34.14%), and noncalculous in 50/82 (61%). The lower third ureter was the most affected level in 48/82 ureters (58.5%). The total sensitivity and accuracy of CPR for the cause of the ureteric obstruction (97.5% and 95.3%, respectively) were higher than those of 3D VR and its corresponding MIP (75% and 73.2%, respectively). CPR also was more sensitive and accurate (total sensitivity of 100% and accuracy of 100%) compared with those of combined 3D VR and its corresponding MIP (79.5% and 75.9%, respectively) for the level of ureteral obstruction. ConclusionsCPR had superior diagnostic accuracy than 3D VR and MIP in detecting the cause and level of ureteral obstruction.

Three-Dimensional Volume-Rendered Series Complements 2D Orthogonal Multidetector Computed Tomography in the Evaluation of Abnormal Spinal Curvature in Patients at a Major Cancer Center: A Retrospective Review.

Background. Abnormal spinal curvature is routinely assessed with plain radiographs, MDCT, and MRI. MDCT can provide two-dimensional (2-D) orthogonal as well as reconstructed three-dimensional volume-rendered (3-D VR) images of the spine, including the translucent display: a computer-generated image set that enables the visualization of surgical instrumentation through bony structures. We hypothesized that the 3-D VR series provides additional information beyond that of 2-D orthogonal MDCT in the evaluation of abnormal spinal curvature in patients evaluated at a major cancer center. Methods. The 3-D VR series, including the translucent display, was compared to 2-D orthogonal MDCT studies in patients with an abnormal spinal curvature greater than 25 degrees and scored as being not helpful (0) or helpful (1) in 3 categories: spinal curvature; bony definition; additional findings (mass lesions, fractures, and instrumentation). Results. In 38 of 48 (79.2%) patients assessed, the 3-D VR series were scored as helpful in 63 of 144 (43.8%) total possible categories (32 spinal curvature; 14 bony definition; 17 additional findings). Conclusion. Three-dimensional MDCT images, including the translucent display, are complementary to multiplanar 2-D orthogonal MCDT in the evaluation of abnormal spinal curvature in patients treated at a major cancer center.

Aortic Bleeding One Week after Removal of an Intraoperative Epicardial Temporary Pacing Wire

A 56-year-old man had left nephrectomy and resection of a cavoatrial tumor thrombus under a cardiopulmonary bypass assist for left renal cell carcinoma. An intraoperative bipolar temporary epicardial atrial pacing wire was removed on postoperative day 8. The patient collapsed on postoperative day 15. Emergent transthoracic echocardiography and computed tomography scanning with contrast media detected cardiac tamponade. The three-dimensional volume-rendering images from the multislice computed tomography scan demonstrated bleeding from the aortic root. Upon emergency operation, active arterial bleeding from the aortic root distal to the sites of cannulation and cardioplegia was confirmed, and hemostasis with sutures was completed. It is well known that the intraoperative temporary epicardial pacing wire can cause bleeding or arrhythmia, especially when the wire is being removed. However, bleeding usually occurs from the inserted epicardial point of the pacing wire soon after removal of the wire. To our knowledge, this late bleeding complication of the pacing wire is a previously unreported serious iatrogenic complication after cardiac surgery.