Soft Tissue Anatomy Research Articles

Soft tissue imaging with photon counting spectroscopic CT

The purpose of this work was experimental investigation of photon counting spectroscopic CT (PCS-CT) imaging of anatomical soft tissue with clinically relevant size. The imaging experiments were performed using a spectroscopic CT system based on CdZnTe photon counting detector with two rows of pixels, 256 pixels in each row, 1 × 1 mm2 pixel size, and 25.6 cm detector length. The detector could split the x-ray energy spectrum to 5 regions (energy bins), and acquire 5 multi-energy (spectroscopic) CT images in a single CT scan. A sample of round shaped anatomical soft tissue of 14 cm diameter including lean and fat was used for imaging. To avoid the negative effect of anatomical noise on quantitative analysis, a spectroscopic CT phantom with tissue equivalent solid materials was used. The images were acquired at 60, 90, and 120 kVp tube voltages, and spectroscopic image series were acquired with 3 and 5 energy bins. Spectroscopic CT numbers were introduced and used to evaluate an energy selective image series. The anatomical soft tissue with 14 cm diameter was visualized with good quality and without substantial artifacts by the photon counting spectroscopic CT system. The effects of the energy bin crosstalk on spectroscopic CT numbers were quantified and analyzed. The single and double slice PCS-CT images were acquired and compared. Several new findings were observed, including the effect of soft tissue non-uniformity on image artifacts, unique status of highest energy bin, and material dependent visualization in spectroscopic image series. Fat–lean decomposition was performed using dual energy subtraction and threshold segmentation methods, and compared. Using K-edge filtered x-rays improved fat–lean decomposition as compared to conventional x-rays. Several new and important aspects of the PCS-CT were investigated. These include imaging soft tissue with clinically relevant size, single- and double-slice PCS-CT imaging, using spectroscopic CT numbers to quantify multi-energy PCS-CT images, application of K-edge filtered x-rays for improved soft tissue decomposition, and several others. The study suggests that the presented PCS-CT technology meets the requirements of a particular clinical application, i.e. dedicated breast CT.

Percutaneous Intervention in Kyphoscoliosis—Tackling a Tortuosity*

Spine deformities have several associations with compromised cardiorespiratory function. Percutaneous coronary interventions rely on fluoroscopic anatomical landmarks to guide procedures, and distortion of the mediastinal soft tissue and skeletal anatomy in conditions like kyphoscoliosis can pose unique challenges for the interventional cardiologist. Here, we report a case of elderly kyphoscoliotic male patient with worsening angina, who underwent successful percutaneous coronary intervention via the radial route.

Validity of intraoral soft tissue landmarks as reference points for orientation of occlusal plane in natural dentition: A clinical study

Introduction: Occlusal plane is the average plane established by incisal and occlusal surfaces of teeth. Various anatomic landmarks are used to determine this missing component of occlusion which is lost with the loss of teeth. However, variation has been observed in the orientation of occlusal plane determined clinically with different anatomical landmarks as references. Objective: This study was undertaken to determine the relation of intraoral anatomic soft tissue landmarks, namely, retromolar pad and parotid papilla with occlusal plane in natural dentition. Materials and Methods: Irreversible hydrocolloid impressions of 100 edentulous individuals (50 males and 50 females) were made to get the models. A 16 gauge wire was extended from mandibular occlusion plane posteriorly up to retromolar pad to establish their relationship. Furthermore, vertical distance of apex of parotid papilla to maxillary molar cusp tip it opposed (distobuccal cusp of maxillary first molar or mesiobuccal cusp of maxillary second molar), and mandibular molar cusp tip (to which parotid papilla apposed) was measured when the teeth were in maximal intercuspal position. Results: This study determined that the natural occlusal plane is oriented posteriorly at the level corresponding with the lower third of retromolar pad. Mean distance of parotid papilla above the corresponding maxillary cusp tip (while in occlusion) was 5.048 mm, and mean distance of Parotid papilla above the corresponding mandibular molar cusp tip (while in occlusion) was determined to be 3.602 mm. The difference in observed means between males and females or between right and left side was not statistically significant.

Soft-tissue anatomy of the Plesiosaur pectoral girdle inferred from basal Eosauropterygia taxa and the extant phylogenetic bracket

Soft-tissue anatomy of the Plesiosaur pectoral girdle inferred from basal Eosauropterygia taxa and the extant phylogenetic bracket

Articular soft tissue anatomy of the archosaur hip joint: Structural homology and functional implications.

Archosaurs evolved a wide diversity of locomotor postures, body sizes, and hip joint morphologies. The two extant archosaurs clades (birds and crocodylians) possess highly divergent hip joint morphologies, and the homologies and functions of their articular soft tissues, such as ligaments, cartilage, and tendons, are poorly understood. Reconstructing joint anatomy and function of extinct vertebrates is critical to understanding their posture, locomotor behavior, ecology, and evolution. However, the lack of soft tissues in fossil taxa makes accurate inferences of joint function difficult. Here, we describe the soft tissue anatomies and their osteological correlates in the hip joint of archosaurs and their sauropsid outgroups, and infer structural homology across the extant taxa. A comparative sample of 35 species of birds, crocodylians, lepidosaurs, and turtles ranging from hatchling to skeletally mature adult were studied using dissection, imaging, and histology. Birds and crocodylians possess topologically and histologically consistent articular soft tissues in their hip joints. Epiphyseal cartilages, fibrocartilages, and ligaments leave consistent osteological correlates. The archosaur acetabulum possesses distinct labrum and antitrochanter structures on the supraacetabulum. The ligamentum capitis femoris consists of distinct pubic- and ischial attachments, and is homologous with the ventral capsular ligament of lepidosaurs. The proximal femur has a hyaline cartilage core attached to the metaphysis via a fibrocartilaginous sleeve. This study provides new insight into soft tissue structures and their osteological correlates (e.g., the antitrochanter, the fovea capitis, and the metaphyseal collar) in the archosaur hip joint. The topological arrangement of fibro- and hyaline cartilage may provide mechanical support for the chondroepiphysis. The osteological correlates identified here will inform systematic and functional analyses of archosaur hindlimb evolution and provide the anatomical foundation for biomechanical investigations of joint tissues.

Intraprocedural Online Fusion of Echocardiography and Fluoroscopy During Transapical Mitral Valve-in-Valve Implantation

Transapical mitral valve-in-valve implantation using a 29-mm Edwards SAPIEN 3 bioprosthesis (Edwards Lifesciences, Irvine, CA) was successfully performed in a 70-year-old patient with a degenerated bioprosthesis (3-mm SJM Epic; St Jude Medical, St Paul, MN) and severe mitral regurgitation. The procedure was performed under transesophageal echocardiographic and fluoroscopic guidance using the EchoNavigator system Release II (Philips Healthcare, Andover, MA). This innovative technology enables online fusion of both imaging modalities, allowing for simultaneous display of soft tissue anatomy from echocardiography and device structures from fluoroscopy.

Fate of Free Fat Dermis Graft in TMJ Interpositional Gap Arthroplasty: A Long Term MRI Study.

Free fat dermis graft is a good interpositional material for TMJ gap arthroplasty. Analysing the fate of the graft by magnetic resonance imaging (MRI) images helps in excellent visualization of both bony and soft tissue anatomy of the operated TMJ joint as well as in assessing the changes in dermis graft which was previously placed. To investigate the radiological fate of the dermis-fat graft within the TMJ using MRI. Five joints of five patients who had dermis-fat grafts placed in their TMJ following gap arthroplasty were recruited for this study. Each patient had undergone TMJ gap arthroplasty with immediate dermis-fat graft placement. All the patients are then subjected to MRI. Fat graft was identified in close proximity to the mandibular condyle in all cases, with only three joints demonstrating fat covering the entire articular surface of the mandibular condyle. In the remaining joints the interpositional material found in the MRI defined joint space with mainly grey appearance, suggesting tissue change to other than fat, i.e. scar or granulation tissue. When free fat dermis graft is placed as interpositional material the graft occupied the entire TM joint and prevented it from recurrent ankylosis. The graft placed aids in normal functioning of the temperomandibular joint without any complications.

A review of nineteenth-century records of Sowerby's beaked whale (Mesoplodon bidens)

Data on 27 mesoplodont whales are compiled from the original nineteenth century published records from Britain, Ireland, Europe and the United States. These data comprise the type specimen of Sowerby's beaked whale ( Mesoplodon bidens) and 26 other records, all referred to the taxon M. bidens. Records may include the following information: specimen total length, sex, date of discovery and the locality, pigmentation pattern, external morphology, osteology and soft-tissue anatomy. This information is summarized here from the original descriptions. Only a handful of these specimens was externally complete when described at first hand.

Konservat-Lagerstätten 40 Years On: The Exceptional Becomes Mainstream

Since Dolf Seilacher coined the term Konservat-Lagerstätten in 1970, these deposits have migrated from the margins to the mainstream of paleontological research. With greater understanding of the controls on their occurrence, new examples of exceptional preservation continue to be discovered. They provide critical data for phylogenies and stratigraphic ranges. Together with molecular data, they calibrate the history of many infrequently preserved taxa. Ostracods, tiny crustaceans with a biomineralized carapace, illustrate the importance of recent discoveries in Konservat-Lagerstätten. The rare examples with fossilized appendages are preserved in a diversity of ways, organically or through authigenic mineralization. They confirm that ostracods were present at least by the late Ordovician, provide evidence of relationships obscured by the morphology of the routinely preserved valves, and extend the stratigraphic range of particular groups. They reveal extraordinary features of the soft-tissue anatomy of ostracods, including reproductive morphology and strategy. While other taxa would provide equally compelling examples of research progress, it is clear that the concept of exceptional preservation is expanding. Future discoveries and new analytical methods will match the reconstruction of coloration in feathered dinosaurs, for example, for unexpected novelty.

Three-dimensional analysis of elbow soft tissue footprints and anatomy

Tendinous and ligamentous injuries commonly occur in the elbow. This study characterized the location, surface areas, and origin and insertional footprints of major elbow capsuloligamentous and tendinous structures in relation to bony landmarks with the use of a precision 3-dimensional modeling system. Nine unpaired cadaveric elbow specimens were dissected and mounted on a custom jig. Mapping of the medial collateral ligament (MCL), lateral ulnar collateral ligament (LUCL), triceps, biceps, brachialis, and capsular reflections was then performed with 3-dimensional digitizing technology. The location, surface areas, and footprints of the soft tissues were calculated. The MCL had a mean origin (humeral) footprint of 216 mm(2), insertional footprint of 154 mm(2), and surface area of 421 mm(2). The LUCL had a mean origin footprint of 136 mm(2), an insertional footprint of 142 mm(2), and a surface area of 532 mm(2). Of the tendons, the triceps maintained the largest insertional footprint, followed by the brachialis and the biceps (P < .001-.03). The MCL, LUCL, and biceps footprint locations were consistent, with little variability. The surface areas of the anterior (1251 mm(2)) and posterior (1147 mm(2)) capsular reflections were similar (P = .82), and the anterior capsule extended farther proximally. Restoring the normal anatomy of key elbow capsuloligamentous and tendinous structures is crucial for effective reconstruction after bony or soft tissue trauma. This study provides the upper extremity surgeon with information that may aid in restoring elbow biomechanics and preserving range of motion in these patients.

Definition and visualisation of regions of interest in post-prostatectomy image-guided intensity modulated radiotherapy.

IntroductionStandard post-prostatectomy radiotherapy (PPRT) image verification uses bony anatomy alignment. However, the prostate bed (PB) moves independently of bony anatomy. Cone beam computed tomography (CBCT) can be used to soft tissue match, so radiation therapists (RTs) must understand pelvic anatomy and PPRT clinical target volumes (CTV). The aims of this study are to define regions of interest (ROI) to be used in soft tissue matching image guidance and determine their visibility on planning CT (PCT) and CBCT.MethodsPublished CTV guidelines were used to select ROIs. The PCT scans (n = 23) and CBCT scans (n = 105) of 23 post-prostatectomy patients were reviewed. Details on ROI identification were recorded.ResultsEighteen patients had surgical clips. All ROIs were identified on PCTs at least 90% of the time apart from mesorectal fascia (MF) (87%) due to superior image quality. When surgical clips are present, the seminal vesicle bed (SVB) was only seen in 2.3% of CBCTs and MF was unidentifiable. Most other structures were well identified on CBCT. The anterior rectal wall (ARW) was identified in 81.4% of images and penile bulb (PB) in 68.6%. In the absence of surgical clips, the MF and SVB were always identified; the ARW was identified in 89.5% of CBCTs and PB in 73.7%.ConclusionsSurgical clips should be used as ROIs when present to define SVB and MF. In the absence of clips, SVB, MF and ARW can be used. RTs must have a strong knowledge of soft tissue anatomy and PPRT CTV to ensure coverage and enable soft tissue matching.

An image-based method to automatically propagate bony landmarks: application to computational spine biomechanics

In attempts to elucidate the underlying mechanisms of spinal injuries and spinal deformities, several experimental and numerical studies have been conducted to understand the biomechanical behavior of the spine. However, numerical biomechanical studies suffer from uncertainties associated with hard- and soft-tissue anatomies. Currently, these parameters are identified manually on each mesh model prior to simulations. The determination of soft connective tissues on finite element meshes can be a tedious procedure, which limits the number of models used in the numerical studies to a few instances. In order to address these limitations, an image-based method for automatic morphing of soft connective tissues has been proposed. Results showed that the proposed method is capable to accurately determine the spatial locations of predetermined bony landmarks. The present method can be used to automatically generate patient-specific models, which may be helpful in designing studies involving a large number of instances and to understand the mechanical behavior of biomechanical structures across a given population.

Surgically Relevant Bony and Soft Tissue Anatomy of the Proximal Femur.

Background:Hip endoscopy facilitates the treatment of extra-articular disorders of the proximal femur. Unfortunately, current knowledge of proximal femur anatomy is limited to qualitative descriptions and lacks surgically relevant landmarks.Purpose:To provide a quantitative and qualitative analysis of proximal femur anatomy in reference to surgically relevant bony landmarks.Study Design:Descriptive laboratory study.Methods:Fourteen cadaveric hemipelvises were dissected. A coordinate measuring device measured dimensions and interrelationships of the gluteal muscles, hip external rotators, pectineus, iliopsoas, and joint capsule in reference to osseous landmarks.Results:The vastus tubercle, superomedial border of the greater trochanter, and femoral head-neck junction were distinct and reliable osseous landmarks. The anteroinferior tip of the vastus tubercle was 17.1 mm (95% CI: 14.5, 19.8 mm) anteroinferior to the center of the gluteus medius lateral insertional footprint and was 22.9 mm (95% CI: 20.1, 25.7 mm) inferolateral to the center of the gluteus minimus insertional footprint. The insertions of the piriformis, conjoint tendon of the hip (superior gemellus, obturator internus, and inferior gemellus), and obturator externus were identified relative to the superomedial border of the greater trochanter. The relationship of the aforementioned footprints were 49% (95% CI: 43%, 54%), 42% (95% CI: 33%, 50%), and 64% (95% CI: 59%, 69%) from the anterior (0%) to posterior (100%) margins of the superomedial border of the greater trochanter, respectively. The hip joint capsule attached distally on the proximal femur 18.2 mm (95% CI: 14.2, 22.2 mm) from the head-neck junction medially on average.Conclusion:The vastus tubercle, superomedial border of the greater trochanter, and the femoral head-neck junction were reliable osseous landmarks for the identification of the tendinous and hip capsular insertions on the proximal femur. Knowledge of the interrelationships between these structures is essential for endoscopic navigation and anatomic surgical repair and reconstruction.Clinical Relevance:The qualitative and quantitative clinically relevant anatomic data presented here will aid in the diagnosis of proximal femur pathology and will provide a template for anatomic repair or reconstruction.

TU‐F‐BRF‐04: Registration of 3D Transesophageal Echocardiography and X‐Ray Fluoroscopy Using An Inverse Geometry X‐Ray System

Purpose:To develop a method for the fusion of 3D echocardiography and Scanning‐Beam Digital X‐ray (SBDX) fluoroscopy to assist with catheter device and soft tissue visualization during interventional procedures.Methods:SBDX is a technology for low‐dose inverse geometry x‐ray fluoroscopy that performs digital tomosynthesis at multiple planes in real time. In this study, transesophageal echocardiography (TEE) images were fused with SBDX images by estimating the 3D position and orientation (the “pose”) of the TEE probe within the x‐ray coordinate system and then spatially transforming the TEE image data to match this pose. An initial pose estimate was obtained through tomosynthesis‐based 3D localization of points along the probe perimeter. Position and angle estimates were then iteratively refined by comparing simulated projections of a 3D probe model against SBDX x‐ray images. Algorithm performance was quantified by imaging a TEE probe in different known orientations and locations within the x‐ray field (0‐30 degree tilt angle, up to 50 mm translation). Fused 3D TEE/SBDX imaging was demonstrated by imaging a tissue‐mimicking polyvinyl alcohol cylindrical cavity as a catheter was navigated along the cavity axis.Results:Detected changes in probe tilt angle agreed with the known changes to within 1.2 degrees. For a 50 mm translation along the source‐detector axis, the detected translation was 50.3 mm. Errors for in‐plane translations ranged from 0.1 to 0.9 mm. In a fused 3D TEE/SBDX display, the catheter device was well visualized and coincident with the device shadow in the TEE images. The TEE images portrayed phantom boundaries that were not evident under x‐ray.Conclusion:Registration of soft tissue anatomy derived from TEE imaging and device imaging from SBDX x‐ray fluoroscopy is feasible. The simultaneous 3D visualization of these two modalities may be useful in interventional procedures involving the navigation of devices to soft tissue anatomy.

SU‐E‐J‐114: Towards Integrated CT and Ultrasound Guided Radiation Therapy Using A Robotic Arm with Virtual Springs

Purpose:Currently there is an urgent need in Radiation Therapy for noninvasive and nonionizing soft tissue target guidance such as localization before treatment and continuous monitoring during treatment. Ultrasound is a portable, low cost option that can be easily integrated with the LINAC room. We are developing a cooperatively controlled robot arm that has high intrafraction reproducibility with repositioning of the ultrasound probe. In this study, we introduce virtual springs (VS) to assist with interfraction probe repositioning and we compare the soft tissue deformation introduced by VS to the deformation that would exist without them.Methods:Three metal markers were surgically implanted in the kidney of one dog. The dog was anesthetized and immobilized supine in an alpha cradle. The reference ultrasound probe position and force to ideally visualize the kidney was defined by an experienced ultrasonographer using the Clarity ultrasound system and robot sensor. For each interfraction study, the dog was removed from the cradle and re‐setup based on CBCT with bony anatomy alignment to mimic regular patient setup. The ultrasound probe was automatically returned to the reference position using the robot. To accommodate the soft tissue anatomy changes between each setup the operator used the VS feature to adjust the probe and obtain an ultrasound image that matched the reference image. CBCT images were acquired and each interfraction marker location was compared with the first interfractionResult. Results:Analysis of the marker positions revealed that the kidney was displaced by 18.8 ± 6.4 mm without VS and 19.9 ± 10.5 mm with VS. No statistically significant differences were found between two procedures.Conclusion:The VS feature is necessary to obtain matching ultrasound images, and they do not introduce further changes to the tissue deformation. Future work will focus on automatic VS based on ultrasound feedback.Supported in part by: NCI R01 CA161613; Elekta Sponsored Research

SU‐E‐J‐44: Design a Platform and Phantom Model for Photoacoustic Imaging in Combination with CT

Purpose:Our (long‐term) objective is to develop a US manipulator that will provide in situ radiation response and image‐guided therapy for bladder cancer based on photoacoustic molecular imaging.Methods:A platform was devised to provide a reproducible positional frame of reference for targeting anatomic structure between MDCT and US scans, in lieu of CBCT, and to fuse photoacoustic molecular imaging. US and photoacoustic scans are taken of a patient while in the CT scanner and IRMT. Through co‐registration, based on anatomical positions, we identified a common coordinate system to be used in Eclipse. A bladder phantom was constructed to validate anatomical tracking via US and photoacoustic imaging. We tested the platform using phantom model to demonstrate validity once moved from the CT couch to the linear accelerator couch.Results:This platform interlocks with Varian exact couch index points for reproducibility of positioning. Construction from low Z material and sized appropriately to fit in CT/IMRT gantry. Error in conversion from cylindrical coordinates of the manipulator to X, Y, Z coordinates of the treatment couch was less than 1mm. We measured the bladder size in 3 different directions in both Eclipse from the CT and Acuson from US. The error was less than 2mm in all directions. CT and US images were co‐registered in MATLAB. Co‐registration of photoacoustic images is still being developed.Conclusion:For Linear Accelerators without on board imaging, MV portal images are not a viable option for the localization of soft tissue anatomy. We believe our manipulator provides an alternative using US imaging, which will be examined in an upcoming clinical trial. We plan to examine the value of hypoxia guided treatment through photoacoustic imaging during this trial.

A simplified arthroscopic bone graft transfer technique in chronic glenoid bone deficiency.

In severe shoulder instability, chronic glenoid bone deficiency is a challenge for arthroscopic shoulder surgeons. This paper presents a new all-arthroscopic technique of iliac crest bone graft transfer for those patients. Transportation through the rotator interval and repositioning into the glenoid defect is achieved by use of a tracking suture, while fixation of the graft is performed by biodegradable or titanium double-helix screws. Overall, the feasibility and reproducibility of this new reconstruction technique in recreating the bony and soft tissue anatomy of the antero-inferior glenoid could be demonstrated. So far, preliminary outcomes of 24 patients operated on using this technique are promising. Level of evidence Case series with no comparison group, Level IV.

Glenohumeral Contact Pressure With Simulated Anterior Labral and Osseous Defects in Cadaveric Shoulders Before and After Soft Tissue Repair

Background: Glenoid rim fractures and erosion can result from traumatic and repeated shoulder dislocations, leading to glenoid bone loss. Traditional instability surgery includes Bankart repair to restore soft tissue anatomy, although a recent trend is to address glenoid bone deficiency when appropriate with a bone block procedure. Hypothesis/Purpose: The purpose of this study was to quantify glenohumeral joint contact pressures as a function of anterior labral detachment, progressive anterior glenoid bone loss, and labral repair. The hypothesis was that a critical glenoid defect size exists whereby labral repair alone cannot restore joint contact pressures, therefore favoring bone block augmentation over soft tissue repair. Study Design: Controlled laboratory study. Methods: Eight fresh-frozen cadaveric shoulders were tested under a 440-N compressive load simulating glenohumeral abduction positions of 30° and 60° in neutral rotation and 60° with 90° of external rotation. Glenohumeral joint contact pressures were recorded with a Tekscan pressure sensor system in these configurations: (1) intact specimen, (2) Bankart lesion, (3) 10% anterior rim bone defect, (4) 10% bone defect with labral repair, (5) 20% bone defect, (6) 20% bone defect with labral repair, (7) 30% bone defect, and (8) 30% bone defect with labral repair. The joint contact pressures were compared at all configurations. Results: The Bankart lesion and 10%, 20%, and 30% glenoid defects showed significant (P < .05) increases in mean contact pressures over baseline values. Labral repair at 10% bone loss reduced mean contact pressures to below the intact state, and labral repair of 20% defects demonstrated normalized mean contact pressures. However, mean contact pressures remained statistically elevated compared with baseline values after labral repair of 30% glenoid defects. Conclusion: Glenohumeral joint contact pressures were restored to baseline values after labral repair of 10% and 20% anterior glenoid bone defects. Conversely, labral repair at 30% glenoid bone loss did not restore glenohumeral contact mechanics, yielding elevated contact pressures despite repair. Further study is warranted to investigate the stability (resistance to dislocations) of the glenohumeral joint after labral repair and bone block augmentation. Clinical Relevance: A critical glenoid defect size exists in which labral repair alone does not restore normal glenohumeral contact pressures. Surgeons should carefully evaluate glenoid bone loss before selecting a surgical treatment for shoulder instability.

A review of radiological imaging in the hand and wrist

Abstract Wrist injuries are common and ongoing wrist pain is a cause of functional loss in the general population especially affecting the younger population. It is a complex joint comprised of the distal radio-ulnar joint (DRUJ), the radio-carpal joint (RCJ), the intercarpal joints and the carpo-metacarpal joint (CMCJ). The primary radiological investigation of the wrist is plain film radiography. Advanced imaging techniques play an important role in evaluating the complex anatomy of bone and soft tissues of the wrist. This is a result of the bony arrangement, multiple ligamentous structures and triangular fibrocartilage complex (TFCC), which provide much needed support to the wrist. As such, second line investigations including ultrasound (USS), computerized tomography (CT) and magnetic resonance imaging (MR) are increasingly used to diagnose wrist pathologies. These modalities allow a more focused assessment of the bony and soft tissue structures in this region. This in turn can enable faster diagnosis of a patient's condition, leading to a more efficient management plan and a quicker return to functional activity. We hereby, present an educational review from an imaging perspective that demonstrates a range of pathologies that would otherwise be missed or unapparent if advanced imaging is not utilised.

Mandibular Reconstruction With Iliac Crest Free Flap, Nasolabial Flap, and Osseointegrated Implants

Oncologic patients undergoing segmental mandibulectomy with soft tissue resection develop several esthetic and functional sequelae; therefore, the defect must be reconstructed immediately. The iliac crest flap is the only flap that allows reconstruction of the previous dimensions of the mandible. However, the excessive soft tissue of this flap prevents optimal reconstruction of intraoral soft tissue defects. This report describes a reconstructive technique used in 12 patients who underwent segmental mandibulectomy because of soft tissue defects resulting from tumor resection. The technique involves reconstruction of the mandible using an iliac crest flap combined with a nasolabial flap to enable subsequent reconstruction of the intraoral soft tissue and immediate placement of osseointegrated implants. The osseointegration success rate was 95.2% with a failure rate of 4.8%. Failure particularly affected the irradiated patients. Excellent functional and aesthetic results were obtained with the iliac crest free flap, nasolabial flap and osseointegrated dental implants. This technique has several advantages. On the one hand, it enables reconstruction of the original dimensions of the mandible, thus allowing immediate placement of implants in an ideal position for subsequent rehabilitation with a dental prosthesis. On the other hand, the nasolabial flap provides a thin layer of tissue that can be used to reconstruct the anatomy of the oromandibular soft tissue.