Total ankle/total talus replacement - Retrospective comparison of surgeon decision relative to three-dimensional joint health assessment.

Treatment of end-stage ankle conditions is a complex challenge in foot and ankle surgery. The talus is prone to issues such as osteoarthritis (OA) and avascular necrosis (AVN). Patient-specific total ankle and total talus replacement (TATTR) procedures have emerged as potential solutions, but the decision to include subtalar arthrodesis in these surgeries is multifaceted. In this study, we aimed to understand the relationship between past surgeon decisions for fusion with TATTR and three-dimensional joint health assessments using preoperative CT data. Twenty-seven TATTR with subtalar fusion and 19 TATTR without subtalar fusion were analyzed. Each patient underwent a bilateral computed tomography scan, which was segmented prior to surgery. Distance mapping of various subtalar regions was performed, and average distance was reported. For better analysis, the sinus tarsi was divided into four sectors and the calcaneus posterior facet into nine sectors. Statistical analysis involved calculating the difference in means between the fused and unfused cases. The fusion group exhibited significant joint space narrowing in the posterolateral aspect of the sinus tarsi (p = 0.021). Conversely, on the posterior facet of the subtalar joint, the fusion group showed significant joint space widening in both the anteromedial (p = 0.025) and middle/medial (p = 0.032) sections. Surgeons' decision to perform subtalar arthrodesis in TATTR procedures often aligns with clinical signs of sinus tarsi impingement, as evidenced by significant changes in joint space measurements. While joint health assessments play a pivotal role, other factors, such as surgeon preference and patient-specific considerations, also influence decision-making.

Anatomical characteristics of superior and pulmonary subsuperior segment in right lower lobe based on three-dimensional reconstruction.

OBJECTIVE: Segmentectomy has been widely performed in clinical practice, which required a comprehensive understanding of anatomical structure. In right lower lobe, studies of superior segment (S6) were relatively small-sized. And only one study focusing on subsuperior segment (S∗) was published, which showed different results with previous ones. As the close relationship between S6 and S∗, variation types and their prevalence rate were reported, aiming to providing larger-size study of S6 and showing new evidence on anatomical structure of S∗. METHODS: 800 CT imaging data were collected from patients in our hospital. Three-dimensional reconstruction was performed after quality check. All images were screened according to the definition of corresponding segment and anatomical variations were analyzed. RESULTS: The proportion of S6 variation types in the largest scale (718 patients) was reported with no significant difference compared to previous studies and newly classified subtypes of two-stem V6. The prevalence rate for S∗ in right lower lobe reached 28.3 % (203/718) with similar proportion of three types. Variation types and origins of pulmonary artery were analyzed in detail, finding two-stem A∗ only be observed in type III B∗. CONCLUSIONS: Through this study, the variation types and incidence rate of S6 were confirmed, and a different result of S∗ has been provided as well. The feasibility of the current classification standards and proposed new subclassifications were verified. The results would be a supplement to lung segmental anatomy and could advance researches in the future.

Weightbearing Computed Tomography vs Conventional Tomography for Examination of Varying Degrees of Lisfranc Injures: A Systematic Review of the Literature.

Background: Lisfranc injuries, if not accurately diagnosed, can result in chronic pain and instability. Previous studies have examined ultrasonographs, radiographs, magnetic resonance imaging (MRI), and conventional computed tomography (CT) scan to differentiate Lisfranc instability, but they focused on a healthy/injured scale without differentiating subtle injury. Weightbearing CT (WBCT) has emerged as a diagnostic tool for detecting subtle Lisfranc injuries. This systematic review aimed to compare WBCT with conventional CT in diagnosing Lisfranc injury, and the ability to differentiate injuries of varying severities. Methods: The review encompassed PubMed, CINAHL, MEDLINE, SPORTDiscus, and Web of Science databases from inception until July 5, 2023. Inclusion criteria involved studies on CT and/or WBCT for Lisfranc injuries and nonoperative studies. Exclusion criteria composed case reports, commentaries, postoperative imaging studies, pediatric patients, studies with nonobjective radiographic measurements, studies exclusively focused on injury classification, and studies with fewer than 5 patients because of poor statistical power. Data extraction focused on radiographic measurements of the Lisfranc complex, categorized into conventional CT, partial WBCT, and total WBCT. Results: Out of the initially retrieved 489 articles, 9 met the inclusion criteria. Several studies consistently demonstrate that WBCT provides a higher level of accuracy in measuring the Lisfranc area, offering enhanced sensitivity to detect subtle alterations in joint structure. Moreover, WBCT exhibits superior sensitivity in distinguishing between healthy Lisfranc joints and those with injuries, particularly when identifying dorsal ligament damage. This imaging modality allows for the detection of significant variations in critical measurements like first-second metatarsal (M1-M2) distance, first cuneiform (C1)-M2 distance, and joint volumes, enabling a more comprehensive assessment of Lisfranc joint health especially with subtle instability. Conclusion: This review evaluates the extant literature on WBCT's utility in diagnosing Lisfranc injuries and compares its effectiveness to CT in distinguishing between injuries of varying severity. WBCT, with reliable measurement techniques, appears more adept at detecting subtle Lisfranc instability compared to CT, likely by allowing the assessment of injury under load.

An AI-based universal phantom analysis method based on XML-SVG wireframes with novel functional object identifiers.

Objective.Quality assurance (QA) testing must be performed at regular intervals to ensure that medical devices are operating within designed specifications. Numerous QA phantoms and software packages have been developed to facilitate measurements of machine performance. However, due to the hard-coded nature of geometric phantom definition in analysis software, users are typically limited to the use of a small subset of compatible QA phantoms. In this work, we present a novel AI-based universal Phantom (UniPhan) algorithm that is not phantom specific and can be easily adapted to any pre-existing image-based QA phantom.Approach.Extensible Markup Language Scalable Vector Graphics (XML-SVG) was modified to include several new tags describing the function of embedded phantom objects for use in QA analysis. Functional tags include contrast and density plugs, spatial linearity markers, resolution bars and edges, uniformity regions, and light-radiation field coincidence areas. Machine learning was used to develop an image classification model for automatic phantom type detection. After AI phantom identification, UniPhan imported the corresponding XML-SVG wireframe, registered it to the image taken during the QA process, performed analysis on the functional tags, and exported results for comparison to expected device specifications. Analysis results were compared to those generated by manual image analysis.Main results.XML-SVG wireframes were generated for several commercial phantoms including ones specific to CT, CBCT, kV planar imaging, and MV imaging. Several functional objects were developed and assigned to the graphical elements of the phantoms. The AI classification model was tested for training and validation accuracy and loss, along with phantom type prediction accuracy and speed. The results reported training and validation accuracies of 99%, phantom type prediction confidence scores of around 100%, and prediction speeds of around 0.1 s. Compared to manual image analysis, Uniphan results were consistent across all metrics including contrast-to-noise ratio, modulation-transfer function, HU accuracy, and uniformity.Significance.The UniPhan method can identify phantom type and use its corresponding wireframe to perform QA analysis. As these wireframes can be generated in a variety of ways this represents an accessible automated method of analyzing image-based QA phantoms that is flexible in scope and implementation.

Orbital pseudotumor in pediatrics: A single tertiary center experience.

Orbital pseudotumor is a rare condition characterized by an idiopathic inflammatory process of the orbit with a polymorphous lymphoid infiltrate. It is misdiagnosed as orbital cellulitis or orbital mass with conjunctivitis in children.

Cross-sectional imaging findings of cardiac outpouchings.

A cardiac outpouching (CO) is a protrusion in a heart chamber's internal anatomical lining. Most COs are clinically insignificant, but some are of vital importance, requiring immediate surgery. Cross-sectional imaging findings of COs, such as location, morphology, size, and accompanying wall motion abnormalities, play an essential role in determining the correct diagnosis and appropriate clinical management. Therefore, radiologists should be familiar with them. This article reviews the key cross-sectional imaging findings and differential diagnoses of COs.

Retrospective audit of CT scans performed at a hospital for surgical patients.

Introduction: Easy accessibility, high sensitivity and specificity of CT scans have markedly increased its usage in developed countries. Its importance is undeniably considered integral for the diagnosis of various pathologies. However, sometimes this costly resource is wasted when used unnecessary. This paper is an audit on CT scans performed to look for surgical pathologies between July 2018 and April 2019 recapitulating the numbers of CT scan's abnormal and normal findings. Methodology: Anonymized record of all the patients seen by the surgical team in the emergency department was reviewed. Retrospective data of every patient who had the CT scan was taken through Mckesson Radiology software of an Irish Hospital. Analysis was done using SPSS. Findings of 102 CT scans was broken down in to three different groups depending at which departmental level CT was performed, namely:Emergency department, Inpatient and Outpatient. Results: 102 CT Scans were performed of which 51 (50%) patients out of all the three groups had unremarkable. Conclusions: Adequate history, proper clinical examination and strong clinical knowledge may bring down the number of unnecessary CT scans.

An unusual case of spontaneous rupture of the renal pelvis.

Spontaneous rupture of the renal pelvis is a relatively rare urologic finding. It is associated with obstructing ureteral calculi and can occur with or without urinary instrumentation. Spontaneous rupture is typically diagnosed through imaging modalities such as computed tomography (CT) scans or retrograde pyelography. In this case report, we detail a case regarding spontaneous rupture of the renal pelvis (SRRP) of a 33-year-old male with idiopathic extravasation of contrast from the renal pelvis discovered on delayed phase CT scan of the abdomen and pelvis. This is a unique case of SRRP as the etiology remains idiopathic.

Acetabular Morphology and Spinopelvic Characteristics: What Predominantly Determines Functional Acetabular Version?

BACKGROUND: In addition to the relative size of the acetabular rim and how the pelvis is positioned in space, the plane in which the acetabular version is calculated also affects its measurement. PURPOSE: To determine the relative contribution of pelvic and acetabular characteristics on morphological version (measured relative to the anterior pelvic plane angle [APPA]) and functional version (measured relative to the horizontal table). STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Included were 50 acetabular dysplasia patients and 109 asymptomatic controls. Using image analysis software, morphological parameters of the pelvis and acetabulum were determined from 2-dimensional computed topography: pelvic incidence, pelvic tilt angle, sacral slope, APPA, morphological and functional acetabular versions, and subtended angles (measure of acetabular rim prominence relative to the femoral head center) around the acetabular clockface in 30° increments. Correlation and multivariable regression analyses were performed with morphological and functional version as dependent variables and spinopelvic and acetabular parameters as independent variables. RESULTS: Morphological version was moderately associated with differences between anterior and posterior subtended angles (R = 0.68 [P < .001] and R = 0.57 [P < .001] for differences at 165° and 15° and 135° and 45°, respectively). Functional version was moderately associated with pelvic tilt angle (R = 0.56; P <.001) and the difference in subtended angles between anterior and posterior rims (R = 0.61 [P < .001] and R = 0.50 [P < .001] for differences at 165° and 15° and 135° and 45°, respectively). Multivariate analysis revealed a good model for predicting morphological version (R 2 = 0.44; P < .01) and functional version (R 2 = 0.58; P < .01). Subtended angle difference between 165° and 15° (B = 0.36 [95% CI, 0.24-0.49]; P < .001) was most strongly related to morphological version, and pelvic tilt angle (B = 0.57 [95% CI, 0.46-0.68]; P < .001) was most strongly related to functional version. CONCLUSION: Functional acetabular version was influenced most strongly by pelvic tilt angle rather than the relative prominence of the acetabular rims. Before determining surgical management for version abnormalities, it would be prudent to assess pelvic mobility and characteristics in different functional positions. In patients with minimal pelvic tilt change dynamically, corrective osteotomy would be the treatment of choice to improve functional version.

Accuracy of Weightbearing CT Scans for Patient-Specific Instrumentation in Total Ankle Arthroplasty.

BACKGROUND: Total ankle arthroplasty (TAA) is a popular and viable option for end-stage ankle arthritis. Posttraumatic arthritis is the most common etiology of ankle arthritis, which creates the additional challenge of osseus deformity. Accuracy and reproducibility in placing the implant on the mechanical axis has been shown to be paramount in all joint arthroplasty including total ankle replacement. Patient-specific preoperative navigation is a relatively new technology for TAA, and up until this past year has been based off of nonweightbearing (NWBCT) or simulated weightbearing computed tomography (WBCT). Our institution has created a protocol to use WBCT in the preoperative patient-specific navigation for TAA using the Prophecy system. The purpose of our study was to compare the accuracy and reproducibility of implant alignment and size using WBCT vs prior studies using NWBCT for the Prophecy reports. METHODS: All patients from July 2019 through October 2020 who underwent TAA were evaluated. Inclusion criteria consisted of primary TAA using patient-specific preoperative navigation who had postoperative radiographs in the 4-6-week time frame. Prophecy predictions and measurements were then compared to actual implant placement and size. RESULTS: Ten patients met our inclusion criteria of WBCT Prophecy preoperative planning using 2 different implant systems. Preoperative deformities in this cohort were small. The average postoperative coronal alignment was 0.84 degrees, range 0.19 to 2.4 degrees. Average postoperative sagittal plane deformity was 1.9 degrees, range 0.33 to 5.05 degrees. Tibial component size was properly predicted in all patients, talar component in 9 of 10. CONCLUSION: This initial report supports accuracy and reproducibility in preoperative patient-specific navigation when using WBCT for TAA with these implants. All TAAs were within the intended target of less than 5 degrees varus or valgus. LEVEL OF EVIDENCE: Level III, retrospective comparative analysis.

Sarcopenia como factor predictivo de dehiscencia de anastomosis en pacientes operados de cáncer de colon / Predictive value of sarcopenia for anastomotic dehiscense in colon cancer surgery

Resumen Introducción: Una complicación importante de la cirugía colorrectal es la dehiscencia de anastomosis (DA). El estado nutricional es uno de los factores importantes en la DA. Una forma objetiva para evaluar nutricionalmente a los pacientes es medir la sarcopenia, definida como disminución de masa muscular esquelética, que puede ser objetivada por análisis de Unidades Hounsfield (UH) y área muscular (AM) por medio de Tomografía Computarizada de Abdomen y Pelvis (TCAP). Objetivo: Evaluar si existe relación entre la DA y la presencia de sarcopenia detectada por medición de UH y AM en TCAP en pacientes sometidos a colectomía por cáncer. Materiales y Método: Estudio de casos y controles con estadística analítica. Se eligen de manera aleatoria 21 pacientes con DA y 40 sin DA. Se incluyen > 18 años, con colectomía por cáncer y anastomosis primaria. Fueron excluidos pacientes ostomizados, que no tuvieran TCAP preoperatoria o que éste no permitiera medir UH y AM. La evaluación imagenológica fue realizada por radiólogo experto. Resultados: La comparación entre grupos evidencia que son homogéneos con respecto al sexo (predomino hombres), edad (promedio 60 años) y localización. Se evidencia signos imagenológicos sugerentes de sarcopenia en el grupo de DA, puesto que existe disminución en UH con valores estadísticamente significativos y tendencia a presentar valores menores en el AM. Conclusiones: La presencia de sarcopenia evaluada por alteración de UH en estudio radiológico se correlaciona con DA, pudiendo ser un predictor de riesgo. La importancia de este hallazgo es que es un factor de riesgo potencialmente corregible.

Introduction: An important complication of colorectal surgery is anastomotic dehiscence (AD). Nutritional status is one of the important factors in AD. An objective way to evaluate the patients' nutritional status is to measure sarcopenia, which is the reduction of skeletal muscle mass. It is possible to standardize Sarcopenia using the analysis of the Hounsfield Units (HU) and the muscular area (MA) which consider Computed Tomography of Abdomen and Pelvis (CTAP). Aim: To evaluate whether there is a relationship between AD and the presence of sarcopenia detected by the measurement of HU and MA using CTAP. The situation considers patients undergoing colectomy for cancer. Materials and Method: Cases and controls were studied with analytical statistics. 21 patients with AD and 40 without AD were chosen randomly. They include > 18 years, with colectomy for cancer and primary anastomosis. Ostomized patients, who previous the surgery do not have CTAP or if it was not available to measure HU and MA, were excluded. The imaging evaluation was performed by an expert radiologist. Results: The comparison between groups shows that they are homogeneous with respect the sex (predominant men), age (average 60 years) and location. There are signs of imaging which suggest the presence of sarcopenia in the AD group. This is explained because there is an important statistical decrease in the HU values and a tendency to present lower MA values. Conclusions: The presence of sarcopenia due to alteration of HU in a radiological study is correlated with AD, and could be a predictor of risk. The importance of this finding is that this risk factor is potentially correctable.

Interantral alveolar ridge splitting for maxillary horizontal expansion and simultaneous dental implant insertion: A case report.

INTRODUCTION: Dental implants present an advanced technique for the rehabilitation of partial or edentulous patients. Tooth loss caused by caries, periodontal disease or systemic factors often results in a decline of the bucco-lingual alveolar ridge dimension. Within one year the initial bone width can be resorbed up to 50%. As a consequence dental implants may be limited for rehabilitation and cannot be performed in a conventional manner because of the risk of dehiscence and fenestrations. Bone blocks, guided bone regeneration (GBR), horizontal osteogenic distraction and bone grafts may be used for augmentation procedures. In case of sufficient vertical bone dimension, an alveolar ridge splitting and augmentation technique (ARST) can be conducted. This case has been reported in line with PROCESS criteria [1]. CASE PRESENTATION: We present a 51-year old female patient, who has had a full denture for about 30 years. The reason for consultation was the demand for a fixed prosthesis. Dental implants in combination of the ARST with GBR allowed us to correct horizontal deformities of the alveolar ridge. DISCUSSION: We discuss the possibility of using the ARST in the interantral region for a full arch rehabilitation of the maxilla with simultaneous dental implant placement in a narrow alveolar ridge. CONCLUSION: The ARST in addition to simultaneous implant placement with a GBR can be successfully used for a full arch rehabilitation of the maxilla in a narrow alveolar ridge.

Aorto-Right Ventricular Fistula and Paravalvular Leak After Transcatheter Aortic Valve Implantation.

Aorto-right ventricular fistula is a potentially fatal complication following transcatheter aortic valve implantation (TAVI). This paper presents a case of successful percutaneous repair of aorto-right ventricular fistula and paravalvular leak after TAVI by using 3D-printed models for pre-procedural planning, and a review of published aorto-right ventricular fistula cases to date. (Level of Difficulty: Advanced.).

Mesenteric venous thrombosis presenting as gastrointestinal bleeding, a challenging diagnosis.

Acute mesenteric venous thrombosis (MVT) is an uncommon cause of intestinal ischemia and is associated with high morbidity and mortality. Patients with acute MVT often present with gastrointestinal (GI) bleeding and other unspecific findings making the diagnosis challenging. This condition requires emergent treatment. The high rates of misdiagnosis of these patients and subsequently the delay in proper and quick management put patients at increased risk of having a negative outcome. Physicians should suspect acute MVT in patients with GI bleed while also considering other factors such as, a past medical history of pro-thrombotic conditions, past surgical history of splenectomy, symptoms of nausea, vomiting, abdominal pain, physical exam findings of abdominal tenderness and abdominal distention and a laboratory workup indicating leukocytosis and an increased plasma lactic acid level. An increase in the yield of accurate diagnosis of acute MVT is possible if physicians in the ED accurately interpret all these findings. The authors herein present a case of acute MVT in a patient whose initial complaint was GI bleeding and provide a thorough review of the literature of cases of acute MVT presenting with GI bleed.

Quantitative evaluation of regional cerebral blood flow changes during childhood using 123I-N-isopropyl-iodoamphetamine single-photon emission computed tomography.

OBJECTIVE: To quantitatively evaluate regional cerebral blood flow (rCBF) and regional developmental changes during childhood using 123I-N-isopropyl-iodoamphetamine single-photon emission computed tomography (SPECT) and autoradiography. METHODS: We retrospectively analyzed quantitative values of rCBF in 75 children (29 girls) aged between 16 days and 178 months (median: 12 months), whose brain images, including magnetic resonance imaging and SPECT data, were normal under visual inspection at Saitama Children's Medical Center between 2005 and 2015. The subjects had normal psychomotor development, no focal neurological abnormalities, and neither respiratory nor cardiac disease at the time of examination. Regions of interest were placed automatically using a three-dimensional stereotactic template. RESULTS: rCBF was lowest in neonates, who had greater rCBF in the lenticular nucleus, thalamus, and cerebellum than the cerebral cortices. rCBF increased rapidly during the first year of life, reaching approximately twice the adult levels at 8 years, and then fell to approximately adult levels in the late teenage years. Cerebral cortex rCBF sequentially increased in the posterior, central, parietal, temporal, and callosomarginal regions during infancy and childhood. CONCLUSIONS: rCBF changed dramatically throughout childhood and ranged from lower than adult values to approximately two times higher than adult values. It had different trajectories in each region during brain development. Understanding this dynamic developmental change is necessary for SPECT image evaluation in children.

Atypical presentation of gangrenous cholecystitis: A case series.

Gangrenous cholecystitis (GC) is a serious complication of acute cholecystitis that has been associated with increased morbidity. Patient with GC can present with a wide variety of non-specific clinical, laboratory, and imaging characteristics, making the diagnosis challenging. This disease requires emergent treatment, which is why a quick and reliable diagnosis is essential for the wellbeing of the patient. The authors herein present a case of GC in a patient whose initial complaint was intractable hiccups, and provide a thorough review of the literature of cases of GC with atypical presentations.

Preferential use of imaging modalities in staging newly diagnosed rectal cancer: a survey of US radiation oncologists.

BACKGROUND: Accurate staging is crucial for management of patients with newly diagnosed rectal cancer. Endorectal ultrasound (EUS) has been the standard modality in the United States for decades, with magnetic resonance imaging (MRI) now preferred by national guidelines. Positron emission tomography (PET), conversely, is not recommended. The current utilization of imaging modalities by American radiation oncologists in staging newly diagnosed rectal cancer is unknown. METHODS: American radiation oncologists completed an anonymous institutional review board-approved online survey probing their imaging preferences for initial staging of rectal cancer patients. RESULTS: We received 220 responses from American radiation oncologists, with 39% in academic centers and with 45% seeing more than 10 rectal cancer patients per year. Most respondents utilize all three imaging modalities for rectal cancer staging-EUS, MRI and positron emission tomography/computed tomography (PET/CT). Fifty-two percent and 38% of respondents are high utilizers of EUS and MRI, respectively, defined as ordering these tests at least 75% of the time. Forty seven percent were high PET utilizers. The latter was associated with practice in a private setting (P=0.015) and being within 10 years from residency training completion (P<0.01). CONCLUSIONS: Our analysis reveals a dramatic discordance among national guidelines and the practice patterns among American radiation oncologists. More rely on PET for initial staging of rectal cancer patients than on pelvic MRI. Further research needs to determine the most effective imaging work-up of patients with an initial diagnosis of rectal cancer.

A lethal mesenteric gastrointestinal stromal tumor: a case report and review of the literature.

Gastrointestinal stromal tumors (GISTs) arising from the mesentery are very rare. Here, we report a 53-year old man with a huge lobulated cystic-solid tumor in the left lower quadrant of the abdomen, which had been proved clinically and radiographically. Surgical resection showed that the large mass was noted at the mesentery of small intestine. Grossly, the largest diameter of the mass were measured up to 23 cm, and poorly circumscribed. Histological observation demonstrated it as a malignant GIST with positive CD117 (c-kit) staining. Mitotic figures were frequently observed up to 110 per 50 high power fields. Soon after the surgery, the patient experienced local recurrence with quick growth. The patient received targeted therapy (imatinib mesylate) but had no ideal effect. The patient died nine months after the operation because of rapid disease progression.

Management of subsolid pulmonary nodules in CT lung cancer screening.

The distinct appearance and behavior of subsolid pulmonary nodules (SSNs) has resulted in separate recommendations for the management of solitary SSNs, both for incidentally detected as well as for screen detected nodules. However, these guidelines have been based primarily on expert opinion. Recently two studies were published regarding SSNs detected in low-dose computed tomography (LDCT) lung cancer screening, including management advices.

Revealing the face of an ancient Egyptian: synthesis of current and traditional approaches to evidence-based facial approximation.

The technique of forensic facial approximation, or reconstruction, is one of many facets of the field of mummy studies. Although far from a rigorous scientific technique, evidence-based visualization of antemortem appearance may supplement radiological, chemical, histological, and epidemiological studies of ancient remains. Published guidelines exist for creating facial approximations, but few approximations are published with documentation of the specific process and references used. Additionally, significant new research has taken place in recent years which helps define best practices in the field. This case study records the facial approximation of a 3,000-year-old ancient Egyptian woman using medical imaging data and the digital sculpting program, ZBrush. It represents a synthesis of current published techniques based on the most solid anatomical and/or statistical evidence. Through this study, it was found that although certain improvements have been made in developing repeatable, evidence-based guidelines for facial approximation, there are many proposed methods still awaiting confirmation from comprehensive studies. This study attempts to assist artists, anthropologists, and forensic investigators working in facial approximation by presenting the recommended methods in a chronological and usable format.