3D Reconstruction Of CT Scan Research Articles

Strategies of laparoscopic thyroidectomy for treatment of substernal goiter via areola approach.

This study was aimed at exploring the feasibility and strategies of laparoscopic thyroidectomy for treatment of substernal goiter via areola approach. A retrospective analysis was conducted to investigate 15 cases of laparoscopic resection of substernal goiter via the areola approach (laparoscopic group) and 12 cases of open resection of substernal goiter via low-neck collar cervical approach (open group) that was completed between December 2012 and December 2014. Operative time, estimated blood loss, postoperative hospitalization and postoperative complication were compared. Follow-up data were assessed, and the mean duration of follow-up was 24.5±7.5months. The surgery was successfully completed in 14 cases, and 1 case was intraoperatively converted to open surgery. All the procedures were successfully completed in the open group. There was no difference in the mean distance from the inferior border of the excised substernal mass to the sternal notch, operation time, intraoperative estimated blood loss, postoperative hospital stay or the drainage tubes removed. Five cases had transient hypocalcemia after surgery in the laparoscopic group, while 1 case in the open group. There were no cases of hoarseness, dysphagia, lymphatic leakage, dyspnea and death in the two groups. And there were no recurrent cases in the follow-up. Laparoscopic thyroidectomy for the treatment of selected substernal goiter via the areola approach is feasible. Preoperative B-ultrasound and 3D-CT scan reconstruction help to select cases and formulate surgical strategies, and the way that the thyroid is suspended using silk threads intraoperatively can reduce surgical difficulties and risks of intraoperative conversion to open surgery.

Clinico-Radiologic Perspective of a Case of Hemifacial Microsomia.

The term hemifacial microsomia (HFM) was coined by Gorlin and Pindborg (1964) [1]. The spectrum of hemifacial microsomia involves malformation of ear with presence of preauricular skin tags, hypoplasia of mandibular ramus, condyle, maxilla, zygomatic and temporal bones, hypoplasia of facial muscles with soft tissue deficiency and orbital deformity [2]. We report a case of hemifacial microsomia with emphasis on its clinico-radiological features. A 25-year-old male patient presented with complaint of facial asymmetry and difficulty in hearing since birth. The medical, dental, and family history was non-contributory. Extra oral examination revealed obvious facial asymmetry [Table/Fig-1], deviated chin, deformed and low set auricle with large preauricular skin tag [Table/Fig-2], and posteriorly placed corner of mouth resulting in macrostomia on right side of face. Intraorally posterior cross bite, and upward displacement of occlusal cant on right side was seen. The patient was clinically diagnosed as HFM of the right side of the face. Conventional CT scan in axial view revealed malformed condyle and coronoid process with absence of zygomatic arch on right side. Malformed right auditory meatus was seen with the presence of soft tissue mass [Table/Fig-3]. A 3D reconstruction of CT scan in frontal view revealed facial asymmetry in form of hypoplastic zygomatic complex, midline shift and upward occlusal cant on right side. The right mandibular ramus was displaced medially relative to contralateral side and exhibited rudimentary coronoid process [Table/Fig-4]. In right lateral view, hypoplastic and malformed zygomatic arch, ramus and condylar head was seen with rudimentary coronoid process and absence of glenoid fossa [Table/Fig-5]. Based on these clinico-radiologic features, diagnosis of HFM was confirmed. [Table/Fig-1]: Gross facial asymmetry and arrested growth of the right side of the face with macrostomia [Table/Fig-2]: Small, malformed right pinna and the presence of preauricular skin tag [Table/Fig-3]: Axial view of CT shows hypoplastic condylar head and zygomatic arch, malformed right internal and external ear components with absence of mastoid air cells [Table/Fig-4]: 3D reconstruction of CT scan (Frontal view) shows midline shift, hypoplastic maxilla and zygomatic bone, and upward occlusal cant towards right side. Medially deviated right mandibular ramus with rudimentary coronoid process was seen [Table/Fig-5]: A 3D reconstruction of CT scan (Lateral view) shows hypoplastic zygomatic arch, ramus, condylar head, rudimentary coronoid process and absence of glenoid fossa HFM is considered as second most common craniofacial malformation after facial clefts with an estimated prevalence of between 1:5600 and 1:26,550 live births [3,4]. The male to female ratio is 3:2 while ratio of right side to left side involvement is 3:2 [2]. HFM is characterised by extreme variability of expression of the disease. The embryonic “developmental field” of first and second branchial arch responds as a single functioning unit in a similar manner to different insults such as vascular disruption, teratogens and chromosome abnormalities which may be responsible for spectrum of anomalies seen in HFM [3]. Minimal diagnostic criteria for HFM include asymmetric hypoplasia of facial structures with preauricular tags or microtia with or without preauricular skin tags. A 30–50% of the patients have auditory problems as a result of malformations in the middle ear [3,4]. The OMENS classification is the most commonly used classification system. The acronym OMENS designates each of the five major areas of involvement: O = orbital, M = mandibular, E = ear, N = facial nerve, and S = soft tissue [5]. Accordingly present case was classified as O0M2E2N0S2. Multidisciplinary treatment approach is required to manage patients with HFM. Decision about need and type of surgical correction depends upon age and growth status of patient and severity of the skeletal deformity and soft tissue deficiency [2].

Comparison of CT-based patient-specific templating and digital radiography templating in total knee arthroplasty

AimThe aim of the prospective study is to evaluate and compare the accuracy of digital templating and CT-based templating in preoperative planning, in determining the size of the femoral and tibial component in total knee arthroplasty. Materials and methodsA prospective study was conducted to compare the accuracy in predicting the size of the prosthetic components in total knee replacement in 81 patients. Preoperatively, all the patients underwent the same standard protocol including digital radiographs with calibration and a CT scan. A dedicated IMPAX digital software was used to template the radiographs. The CT-based planning was performed on 3D reconstruction of CT scans as per standardized protocol for patient-specific instrumentation. ResultThe planning of digital radiography indicates the correct size in 71% of the cases for the femoral component and 47% for the tibial component. CT-based planning reached an accuracy of 93% for the femur and 54% for the tibia in predicting the exact size. The accuracy reaches 100% for both components if considered the maximum error of one size in CT-based planning. There were no surgical complications in any of the cases. DiscussionThe improvement in the ability to predict the size of the prosthetic components obtained by the CT images is statistically significant compared to that obtained by the radiographic study to predict the size of the tibial and femoral component. CT can indicate the number of size within the maximum error of measurement of one size in 100% of cases and this can be helpful to the surgeon and the organization in terms of trays to be sterilized, OR turnover, and cost savings. It appears that CT-based patient-specific templating is relatively easy to use, less invasive, saves time, and improves the accuracy in the positioning of the prosthetic components.

Morphometric measurements and sexual dimorphism of the piriform aperture in adults

The aim of this study was to evaluate the dimensions (maximal width and length), the size and the shape of the PA and their sexual dimorphism. Using 3D-CT scan reconstructions and landmarks positioning around the piriform aperture and on the face, a collective of 170 non-pathologic subjects (79 female, 91 male) from Marseille (France) was examined in classical and geometric morphometrics methods. The mean width of the piriform aperture was 24.00mm in females and 25.32mm in males, the mean length was 32.54mm in females and 36.35mm in males. The difference between males and females was significant, and our data correlates well with the previously data acquired from humans skulls. Facial measurements also showed a statistically significant dimorphism. In morphometric geometrics, the correlation between the centroïd size and PC1 in the shape space was weak, while this correlation was strong in the size and shape space. Visualization of shape differences was achieved on 2D wireframes. Shape and size analysis of the piriform aperture showed the existence of a significant sexual dimorphism. These results encourage us to go further with functional and imaging correlations.

The effect of multislice CT scan-3D reconstruction in the clinical type and treatment of ankle fracture

Objective To evaluate the value of multislice CT scan-3D reconstruction in the clinical type and treatment of ankle fracture.Methods Ankle fractures in 89 cases,preoperative underwent plain radiography,spiral CT and three-dimensional reconstruction at the same time.According to the Lange-Hansen classification and DanisWeber classification of ankle fractures were classified,the evaluation of 3D reconstruction with spiral CT in ankle fracture treatment in ratsResults The type of Lange-Hansen were as follows:pronation-abduction (PAB) 34 cases;pronation-external rotation(PER) 29 cases ; supination-adduction(SAB) 17 cases ; supination external rotation(SER) 9 cases.The type of Danis-Weber:A type 11 cases,B type 40cases,C type 38 cases.Conclusion Multislice CT scan-3D reconstruction has an important value in the clinical type and treatment of ankle fracture. Key words: Tomography, X-ray computed ; Fractures ; Anke joint

CT 3D reconstruction of the arterial network of anatomic specimens: development of a new contrast medium

Introduction: The development of autologous tissue transfer techniques in plastic surgery has encouraged the research into cutaneous vascularization. This has resulted in the revival of interest in ancient techniques and in the development of new and more effective techniques. Riolano was the first to carry out studies of vascular injection [1]. Various substances have been used to fill blood vessels to facilitate dissection. The discovery of X rays revolutionized the field of vascular anatomy [2]. Barium sulfate was soon replaced by lead oxide as the standard contrast agent for injection studies. However, the toxicity of lead oxide limits the application of these techniques and exposes the operator to risks and raises the issue of its disposal. [3]. Two-dimensional contrast radiography has been the standard for investigating the vascular anatomy of surgical flaps. Today, new imaging techniques are available. Static CT angiography enables to evaluate vascular anatomy in 3D and high detail. The aim of this study is to propose a new contrast formula to visualize the vessels in TC 3D studies [4]. Materials and methods: A new contrast agent for CT injection studies has been developed. First the substance must be evaluated with standard radiography to confirm the X-ray blocking properties. Then, various anatomical, human and animal, specimens have been injected, and subjected to CT scan. The data have been processed with Osirix software for 3D reconstruction. Results: the radiopacity was confirmed. CT scan 3D reconstruction showed a good level of detail. Conclusion: our new formula appears to be effective. The radiopacity of the medium can be adapted to tissue characteristics. Our formula allows an easier dissection and a detailed reconstruction of the vessels. Moreover the final polymer is non-toxic.

Methodology for estimating endocranial capacity in a modern European population

Various methods have been published in the literature to estimate endocranial capacity. These are based on mathematical equations using measurements made directly on the skull or indirectly from X-rays, by filling the skull with various materials, by endocasts both physical and virtual (using 3D CT-scan reconstructions). Each method has its advantages, limits and drawbacks. A useful method is one that is simple, time-efficient, cheap, and reproducible. For this study we estimated endocranial capacity by filling the skull with calibrated glass beads. We used a thorough protocol of tamping to ensure results reproducibility. Intra- and inter-observer trials showed no significant differences. The method was applied to 130 recent French (West European) skulls (65 males and 65 females). Sexual dimorphism was studied using logistic regression functions, discriminant analysis, and neural network. The best results were obtained using the neural network, built with two hidden nodes in the hidden layer and one output node, and trained with a steepest descent algorithm. Our tests show that there is obvious sexual dimorphism ( p < 10 −5) of the weight of the skulls (623.44 ± 106.83 g in males; 548.07 ± 94.57 in females), the weight of the glass beads used to fill the skulls (2379.83 ± 228.92 g in males; 2095.95 ± 145.49 in females), and endocranial capacity (1676.47 cm 3 ± 161.26 in males; 1476.48 ± 102.49 in females), but overlapping between sexes is quite significant. The average ECC in male (1676.5 cm 3) and in female (1476.5 cm 3) subjects is higher than those previously published, which deserves some discussion.

Total hip arthroplasty offset measurement: Is C T scan the most accurate option?

Femoral offset is difficult to precisely evaluate with conventional X-ray techniques. Femoral offset characterizes the balance between body weight and the resistance provided by the abductor muscles. Total hip arthroplasties should respect this balance. Computed tomodensitometry (CT-scan) is more accurate than conventional X-ray to evaluate femoral offset. Sixty-one patients who received unilateral total hip arthroplasties were prospectively included in the study. Femoral offset was measured by three-dimensional CT-scan reconstruction using the "Hip Plan" (Symbios) software. Offset was also determined with conventional X-ray and results were compared. This software can be used to measure leg length by frontal telemetry. It was developed for preoperative-planning of cementless femoral stem implants with modular necks of various lengths and angles. All pre- and postoperative measurements were made according to the same protocol. Femoral offset values in this study were very similar to anatomical values found in the literature. They were significantly higher than values obtained by conventional X-ray by an average of 8%. Implantation of hip replacements resulted in a significant increase in offset (1.88+/-4.71 mm) with a slight variation in leg length. Pre- and postoperative leg length increased slightly in the operated leg by an average of 1.66+/-5.63 mm. Seventeen percent of these femurs had high offset associated with small or average sized proximal medullary canals. This preoperative planning software made it possible to identify these difficulties and to adapt implant components using modular long 8 degrees varus necks to restore high offset. In most of these cases, only small femoral stems could be implanted because of the small size of the intramedullary femoral canal. These individual differences were identified with 3D CT-scan reconstruction and included in the preoperative planning. Moreover, leg length could also be evaluated with this method and included in the preplanning. Compared to conventional X-ray, measurements obtained with this preoperative planning method using 3D CT-scan reconstruction are easy to obtain and not dependent upon test conditions because the frame is placed on the femoral axis. Measurements are not influenced by position inconsistencies or if the hip is fixed in external rotation. The significant number of cases with above average offset confirms the importance of obtaining these measurements and the necessity of adapting the strategy in these cases by using lateralized stems, or, as in our series, modular necks to adjust femoral offset and neck angle. Level III diagnostic prospective study.

Minimally Invasive Spinal Surgery

Purpose Accurate three-dimensional (3D) models of lumbar vertebrae can enable image-based 3D kinematic analysis. The common approach to derive 3D models is by direct segmentation of CT or MRI datasets. However, these have the disadvantages that they are expensive, timeconsuming and/or induce high-radiation doses to the patient. In this study, we present a technique to automatically reconstruct a scaled 3D lumbar vertebral model from a single two-dimensional (2D) lateral fluoroscopic image. Methods Our technique is based on a hybrid 2D/3D deformable registration strategy combining a landmark-to-ray registration with a statistical shape model-based 2D/3D reconstruction scheme. Fig. 1 shows different stages of the reconstruction process. Four cadaveric lumbar spine segments (total twelve lumbar vertebrae) were used to validate the technique. To evaluate the reconstruction accuracy, the surface models reconstructed from the lateral fluoroscopic images were compared to the associated ground truth data derived from a 3D CT-scan reconstruction technique. For each case, a surface-based matching was first used to recover the scale and the rigid transformation between the reconstructed surface model Results Our technique could successfully reconstruct 3D surface models of all twelve vertebrae. After recovering the scale and the rigid transformation between the reconstructed surface models and the ground truth models, the average error of the 2D/3D surface model reconstruction over the twelve lumbar vertebrae was found to be 1.0 mm. The errors of reconstructing surface models of all twelve vertebrae are shown in Fig. 2. It was found that the mean errors of the reconstructed surface models in comparison to their associated ground truths after iterative scaled rigid registrations ranged from 0.7 mm to 1.3 mm and the rootmean squared (RMS) errors ranged from 1.0 mm to 1.7 mm. The average mean reconstruction error was found to be 1.0 mm. Conclusion An accurate, scaled 3D reconstruction of the lumbar vertebra can be obtained from a single lateral fluoroscopic image using a statistical shape model based 2D/3D reconstruction technique. Future work will focus on applying the reconstructed model for 3D kinematic analysis of lumbar vertebrae, an extension of our previously-reported imagebased kinematic analysis. The developed method also has potential applications in surgical planning and navigation.

Don't Forget the 3D-CT Scan in Hip Traumatology Surgery!

Concerning acetabular fractures, the three-dimensional (3D) CT-scan computer reconstructions has been acknowledged in recent times as a useful adjunct in preoperative setting up (1) since it can be used as a qualitative and quantitative instrument for the diagnosis of a variety of hip diseases and for the planning of precise surgical procedures (2). Proper software enables the computer to integrate the data of the individual thin CT slices to make three dimensional volumetric rendering information, therefore enabling preoperative computer simulated plannings of internal fixations and of reduction control intraoperatively. Moreover the actual SpiralCT scanners are almost equivalent in costs and in total radiation dose when compared to the performance of special projections of usual radiographs (3). The capability to rotate the 3D images around a variety of axes (Fig. 1) allows the construction of exceptional images that offer perspectives unobtainable by conventional radiology (4), carrying out a complete model with both external and internal surfaces of the injured site without destroying it. 3D images allow a useful display of the fracture, its irradiation and the dislocation of bone fragments (5), facilitating not only the analysis and detection of post-traumatic dislocations, but also the existence of neoplastic changes or disturbances in the mechanics of joints (6). What is more, when a hip fracture is only suspected but not clearly showed on plain radiographs, a CT scan with 3D reconstruction may be helpful, since it illustrates, when present, the angle and displacement of the fracture. In conclusion, we recommend that you bear in mind the 3D CT scan reconstruction as a useful complementary radiographic examination for complicated hip fractures/dislocations patterns. Don’t forget the 3D-CT scan in hip traumatology surgery!

3D reconstruction of a patient‐specific surface model of the proximal femur from calibrated x‐ray radiographs: A validation studya)

Twenty-three femurs (one plastic bone and twenty-two cadaver bones) with both nonpathologic and pathologic cases were considered to validate a statistical shape model based technique for three-dimensional (3D) reconstruction of a patient-specific surface model from calibrated x-ray radiographs. The 3D reconstruction technique is based on an iterative nonrigid registration of the features extracted from a statistically instantiated 3D surface model to those interactively identified from the radiographs. The surface models reconstructed from the radiographs were compared to the associated ground truths derived either from a 3D CT-scan reconstruction method or from a 3D laser-scan reconstruction method and an average error distance of 0.95 mm were found. Compared to the existing works, our approach has the advantage of seamlessly handling both nonpathologic and pathologic cases even when the statistical shape model that we used was constructed from surface models of nonpathologic bones.

3D reconstruction of the ribs from lateral and frontal X-rays in comparison to 3D CT-scan reconstruction

Subject-specific three-dimensional (3D) reconstructions of the ribs can be obtained from biplanar X-rays. The goal of this study was to evaluate the accuracy and the inter-observer reproducibility of this technique in comparison to CT-scan reconstructions. CT scans and biplanar X-rays were obtained from 50 ribs (from three cadaveric rib cages). Three experienced experimenters reconstructed each rib from biplanar X-rays. Morphometric parameters were then computed from the rib midlines. Differences were computed between parameters obtained from the 3D reconstructions based on biplanar X-rays and from CT scans. The accuracy was computed as the mean of this difference for the 50 ribs from all three experimenters. The inter-observer variability was assessed using the coefficient of variation (CV) between the three observers. The CT-scan reconstructions were considered to be the gold standard in spite of their limitations for rib reconstructions. According to the different linear parameters, the accuracy of the reconstructions was found to be between −6 mm (−2%) and 3 mm, (4%). The accuracy of the current method was close to that of CT-scan reconstructions. The inter-observer variability was between 3% and 6%. Frontal and lateral X-rays are commonly obtained clinically, so 3D reconstructions can be used without increased radiation exposure to the patient.

Noggin Inhibits Postoperative Resynostosis in Craniosynostotic Rabbits

Inhibition of bone formation after surgery to correct craniosynostosis would alleviate the need for secondary surgeries and decrease morbidity and mortality. This study used a single dose of Noggin protein to prevent resynostosis and improve postoperative outcomes in a rabbit model of craniosynostosis. Craniosynostosis is defined as the premature fusion of one or more of the cranial sutures, which causes secondary deformations of the cranial vault, cranial base, and brain. Current surgical intervention involves extirpation of the fused suture to allow unrestricted brain growth. However, resynostosis of the extirpated regions often occurs. Several bone morphogenetic proteins (BMPs), well-described inducers of ossification, are involved in bone healing. This study tested the hypothesis that a postoperative treatment with Noggin, an extracellular BMP inhibitor, can inhibit resynostosis in a rabbit model of human familial nonsyndromic craniosynostosis. Thirty-one New Zealand white rabbits with bilateral coronal suture synostosis were divided into three groups: (1) suturectomy controls (n = 13); (2) suturectomy with BSA in a slow-resorbing collagen vehicle, (n = 8); and (3) suturectomy with Noggin in a slow-resorbing collagen vehicle (n = 10). At 10 days of age, a 3 x 15-mm coronal suturectomy was performed. The sites in groups 2 and 3 were immediately filled with BSA-loaded gel or Noggin-loaded gel, respectively. Serial 3D-CT scan reconstructions of the defects and standard radiographs were obtained at 10, 25, 42, and 84 days of age, and the sutures were harvested for histological analysis. Radiographic analysis revealed that Noggin-treated animals had significantly greater coronal suture marker separation by 25 days and significantly greater craniofacial length at 84 days of age compared with controls. 3D-CT analysis revealed that Noggin treatment led to significantly greater defect areas through 84 days and to increased intracranial volumes at 84 days of age compared with other groups. Histological analysis supported CT data, showing that the untreated and BSA-treated groups had significant healing of the suturectomy site, whereas the Noggin-treated group had incomplete wound healing. These data support our hypothesis that inhibition of BMP activity using Noggin may prevent postoperative resynostosis in this rabbit model. These findings also suggest that Noggin therapy may have potential clinical use to prevent postoperative resynostosis in infants with craniosynostosis.

Superior vena cava syndrome: a 3D CT-scan reconstruction

Fig. 1. (A) Preoperative coronal bi-dimensional CT-scan view. Right atrium is totall obstructed. Ao: ascending aorta; PA: pulmonary artery; LV: left ventricle. (B) Preo visualization due to the lack of contrast dye on this volume rendering threshold comm tricuspid valve (), making posterior anatomical structures visible: right superior pulm (RPA), left atrium (LA). SVC: superior vena cava; IVC: inferior vena cava; PA: pulmon neoplastic infiltration; right atrium oppendage seems not to be involved in the proc

Validity of the anteroposterior talocalcaneal angle to assess congenital clubfoot correction.

The anteroposterior talocalcaneal angle (Kite's angle) is still considered a common parameter for assessing clubfoot correction, although some dissenting opinions about its accuracy have been expressed. The purpose of this study was to evaluate the validity of the anteroposterior talocalcaneal angle for assessing correction of congenital clubfoot in adults who received the treatment as children. SUBJECTS AND METHODS. The anteroposterior talocalcaneal angle was measured in 48 treated idiopathic congenital clubfeet and 28 normal feet of 38 patients at the end of skeletal growth using both standing anteroposterior radiographs and 3D CT scan reconstructions. All the patients had been treated by manipulation, above-the-knee casting, and a complementary posteromedial release operation. The radiographic measurement of the anteroposterior talocalcaneal angle corresponded to the measurement of the same angle on the 3D CT scan reconstructions in only the normal feet and 12 clubfeet. In the other 36 clubfeet, a statistically significant difference of a mean of 15 degrees between the two measurements was noted, and the 3D CT scan reconstructions showed a superimposition of the talus and calcaneus, which had lost their normal anatomic divergence. In these cases, the marked medial angulation of the talar neck allowed a positive measurement of the anteroposterior talocalcaneal angle in the anteroposterior radiographic projection. According to our findings, the measurement of the anteroposterior talocalcaneal angle on radiography was misleading for assessing the degree of hindfoot correction in 75% of the treated congenital clubfeet. We believe that other imaging parameters should be considered instead of this angle to evaluate clubfoot correction.

Personalised 3D reconstruction of proximal femur from low-dose digital biplanar radiographs

Twenty-eight excised nonpathologic human proximal femurs were considered in order to apply and validate a 3D reconstruction method using low-dose biplanar radiographs. The 3D reconstruction technique based on radiographic contour identification (called Non Stereo-Corresponding Contour method) was compared with 3D CT scan reconstruction method. The results showed the feasibility and the accuracy (mean distance error=0.7 mm, 2RMS=20 mm) of this technique applied to the proximal femur. Application of this method on hip joint could allow, with a low dose, calculating 3D structural geometric parameters as femoral neck axis length or femoral neck diameter which are of high interest for planning of surgical acts or computed assisted surgery.

Three-dimensional CT-scan reconstruction of renal calculi. A new tool for mapping-out staghorn calculi and follow-up of radiolucent stones.

The development of CT scanners (CT scan) with continuous rapid spiral acquisition now allows three-dimensional reconstructions of mobile organs such as kidneys. The aim of this study was to appreciate the merits of this new technique in the field of renal lithiasis. This non-invasive technique was applied in 27 renal calculi (23 staghorn and 4 radiolucent stones). The acquisition does not require any injection of contrast material. Reconstruction was carried out by three-dimensional (3D) shaded surface display. 3D reconstruction of calculi permits a precise study of the shape of the stone, and of the number, size and direction of its branches. Therefore, it allows for better planning of the PCNL (number of ports, per-operative pelvi-caliceal exploration ...). Large radiolucent calculi are clearly defined with 3DS, facilitating the follow-up under medical treatment. 3D CT scan reconstruction is a noninvasive, cost-effective method which offers high quality 3D images of renal calculi. These results should spur the more widespread use of this technique.