Radiological Landmarks Research Articles

Fascia Lata Allograft Medial Patellofemoral Ligament Reconstruction—Restore the Nature as Close as Possible

Various surgical techniques for medial patellofemoral ligament (MPFL) reconstruction have been described, commonly using hamstring auto- or allografts. Despite their widespread use, these techniques have limitations due to the tubular structure of the hamstring tendons, which does not match the flat, sail-like anatomy of the MPFL. Furthermore, over- or undertensioning of the graft due to tunnel misplacement remains a significant risk, even if anatomic and radiologic landmarks are used. To address these issues, a fascia lata allograft MPFL reconstruction with assessment of angular anisometry is presented. This technique allows for reconstruction of the MPFL as close as possible to its nature with a flat and wide patellar attachment and a gradual transition of maximal tension across the graft fibers, depending on the knee flexion angle. Precise intraoperative control of predefined graft angular anisometry allows for achievement of the desired amount of tension at specific flexion angles. This mitigates the risk of under- or overtensioning and subsequently ensures proper medial-lateral mobility of the patella.

Radiological Landmarks for Joint Line Level in Challenging Total Ankle Arthroplasty.

Background: Although Total Ankle Arthroplasty (TAA) is primarily performed for post-traumatic ankle arthritis with joint disruption, anatomical landmarks for Joint Line (JL) level are typically preserved. However, severe Post-Traumatic Bone Loss (PTBL) or TAA revision may render some landmarks unidentifiable, challenging JL restoration. Methods: Patients undergoing customized TAA for severe PTBL or revision were enrolled. Custom-made implants, based on 3D CT scans, were designed to address bone defects and provide adequate bone support. Evaluated parameters, measured on bilateral ankle weight-bearing radiographs taken preoperatively and 6-8 months postoperatively, included JL Height Ratio (JLHR) and the distances from JL to the Lateral Malleolus apex (LM-JL), the posterior colliculus of the Medial Malleolus (MM-JL), and the Gissane Calcaneal Sulcus (CS-JL). Reproducibility and variability were assessed, and comparisons were made between radiological parameters measured at TAA and those at the contralateral ankle. Results: Thirteen patients were included. Intra- and interobserver reliability demonstrated excellent values. The least variability was observed in the LM-JL distance. Statistically significant correlations were found between CS-JL and MM-JL distances in the operated limb and between the CS-JL of the operated limb and the contralateral ankle. While TAA parameters did not show statistically significant differences compared with the contralateral ankle, a trend toward proximalization of the JL was noted. Conclusions: This study demonstrated good reproducibility of the analyzed parameters for evaluating JL in TAA among patients with severe PTBL or undergoing revision surgery. However, these parameters cannot be deemed fully reliable. Given their potential weaknesses, it is crucial to identify more reproducible values, preferably ratios.

Radiological landmark of syndesmotic ligament complex by magnetic resonance imaging correlate with fibula free flap harvesting procedure

Preservation of syndesmotic ligaments is crucial for preventing adverse sequelae at the donor site following free fibula osteocutaneous flap harvesting. This study sought to determine the relationship between distal tibiofibular ligaments and the fibular segment to identify radiological landmarks that facilitate safe and precise flap. The distances between the distal tibiofibular ligaments (anterior inferior tibiofibular ligament [AITFL], posterior inferior tibiofibular ligament [PITFL]) and the fibular segment, as well as the lower border of the interosseous membrane, were measured on magnetic resonance imaging (MRI) scans of 296 patients without any perceivable ankle abnormalities. The mean distances (± SD) between the distal end of the fibula and the AITFL, PITFL, and lower interosseous membrane border were 3.0 ± 0.4 cm, 2.6 ± 0.4 cm, and 3.9 ± 0.6 cm, respectively. The distance between the talar dome and the PITFL exhibited a range of 0.0–0.5 cm. Our findings support preserving a distal fibular remnant of at least 4 cm to avoid injury to the syndesmotic ligament throughout fibula osteocutaneous flap harvesting. The talar dome could serve as a useful radiological landmark for identifying the upper border of PITFL during preoperative evaluation, and thus facilitating precise and safe flap procurement.

C-Arm Guidance During Thin Flap Arthroscopic Trochleoplasty for Chronic Patellar Instability

The purpose of this paper is to provide a complete Technical Note for our treatment of choice for recurrent patellar dislocation in cases of trochlear dysplasia, especially in patients with types B and D trochlear dysplasia according to the Dejour classification. Different surgical procedures have been reported for the treatment of recurrent patellar instability. One of the most important anatomic factors to address when treating a recurrent patella dislocation is trochlear dysplasia. Few types of open trochleoplasty have been classically described to treat a dysplastic trochlea. However, in recent years, arthroscopic techniques have been reported to reduce invasiveness and complications as well as to improve accuracy and clinical outcomes. In this technique is described an arthroscopic thin-flap tracheoplasty with the use of C-arm guidance in order to precisely control the bone resection and to verify intraoperatively the disappearance of the radiologic landmarks used for diagnosis and classification of the dysplasia. The advantage of this technique is the precision in removal of the supratrochlear spur and bump, the accurate and delicate reshaping of the sulcus with preservation of cartilage vitality, combined with increased reproducibility and safety.

Reliability of intra-atrial ECG method of insertion of central venous line through right internal jugular vein when compared to formula and radiological landmark method: a prospective randomized study

BackgroundIdeal position of central venous catheter tip should be within 2 cm above and 1 cm below superior vena cava–right atrium (SVC-RA) junction. The objective of the study was to compare intra-atrial ECG method of Central venous catheterization of right internal jugular vein (IJV) with traditional methods. A prospective randomized trial enrolling 90 patients were alternatively allocated to three groups and comparison of intra-atrial electrocardiography, radiological landmark and Pere’s formula method for correct positioning of central venous catheter tip were done and tip position were confirmed with post-procedural TEE (transesophageal echocardiography).ResultsCatheter tip was present at the ideal position in 100% cases in intra-atrial ECG method compared to only 23.4% in formula method and 93.3% in landmark method (p value 0.001). In intra-atrial method group, the central venous catheter tip was placed perfectly in all patients, position of the catheter tip was not acceptable in 71.4% of the patients where formula method is used and not acceptable in 11.1% when landmark method is used (p value 0.001). However, we did not encounter any catheter related complications in any of these groups.ConclusionsIntra-atrial ECG method carries the advantage of ideal positioning of the central venous catheter tip by right IJV route in almost all cases when compared to conventional formula and landmark method to some extent. Also, immediate confirmation and real time verification of central venous catheter (CVC) tip is possible, thereby avoids the need for post-procedural chest X-ray and other methods of central venous placement confirmation like arterial blood gas analysis etc., Hence, intra-atrial ECG method is cost effective and safer for confirmation of CVC tip in all the situations.

Tips and Tricks to Safely Perform an Endoscopic Endonasal Trans-Sphenoidal Pituitary Surgery: A Surgeon's Checklist.

The authors aimed to develop an extensive preoperative checklist of CT scan findings during endoscopic access to the ventral skull base and implement it in clinical practice. A comprehensive literature review was conducted to identify the radiological landmarks crucial to endoscopic skull base surgery. Four electronic databases were searched: PubMed, MEDLINE, EMBASE, and Google Scholar using search terms/keywords such as "radiological landmarks," "endoscopic skull base surgery," "CT scan," "pituitary surgery," "anatomical variations," "internal carotid," "optic nerve," "sphenoid sinus," "pneumatization," "dehiscence," and "protrusion". Inclusion criteria were limited to original articles and systematic reviews published in English, between the years 2000 and 2021, which pertained to the radiological landmarks to be identified during endoscopic skull base surgery. Full-text articles were retrieved and collated into a narrative review focused on a 12-item checklist the authors agreed upon. The mnemonic "O ROAD TO SELLA" was used to represent the checklist and include the following landmarks: Sphenoid Ostium, Sphenoid Rostrum, Onodi cells, Anatomic variations of the sphenoid sinus, Distance between the carotids, Tumor characteristics, Optic nerve dehiscence/protrusion, Septation/insertion of the sphenoid sinus, Entrance to the sellar floor, Lateral recess of the sphenoid sinus, cLinoid process pneumatization, and internal carotid Artery dehiscence/protrusion. The checklist is designed to be used by attending physicians, fellows, and residents and the authors intend to implement it into electronic medical records at the institution's medical center to monitor the outcomes of EEPS after implementation.

The Modified Assessment Tool Based on Scapular Y-View for Global Fatty Infiltration in the Supraspinatus Muscle: Correlation, Predictive Performance, and Reliability Analyses

Background: The accurate evaluation of rotator cuff (RC) fatty degeneration after tears is critical for appropriate surgical decision making and prognosis. However, there is currently no reliable and practical tool to reflect the global fatty infiltration (Global-FI) throughout the 3-dimensional (3D) volumetric RC muscles. Purpose: (1) To determine the correlations between 2 modified assessment tools and the Global-FI and their predictive performances and reliabilities for Global-FI prediction, and (2) to compare these predictive parameters with those of the conventional tool using a single scapular Y-view slice. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: A total of 49 patients with full-thickness RC tears scheduled to undergo arthroscopic repairs were included, and their surgical shoulders underwent 6-point Dixon magnetic resonance imaging preoperatively. The Global-FI was measured by calculating the 3D-volumetric fat fraction (FF) of the whole supraspinatus muscle through all acquired oblique sagittal slices. As a commonly used radiological landmark, the scapular Y-view was used to evaluate single-plane fatty infiltration (Y-FI) by calculating the FF in 1 slice, defined as the conventional assessment tool. Two modified assessment tools expand the analytic imaging by integrating the FFs from the scapular Y-view slice and its neighboring slices, which were calculated by averaging the FFs of these 3 slices (meanY3-FI) and accumulating local 3D-volumetric FFs from 3 slices (volY3-FI), respectively. The correlations between 3 assessment tools and the Global-FI were analyzed, and the predictive performance for Global-FI prediction using these tools was determined by goodness of fit and agreement. Moreover, the inter- and intraobserver reliabilities of these assessment tools were evaluated. Similar analyses were performed in the small-medium, large, or massive tear subgroups. Results: The Y-FI was significantly higher than the Global-FI in all cases and tear size subgroups, while the 2 modified assessment tools (meanY3-FI and volY3-FI) did not significantly differ from the Global-FI. All assessment tools were significantly correlated with the Global-FI, but the meanY3-FI and volY3-FI showed stronger correlations than the Y-FI, which was also determined in different tear sizes. Moreover, the regression models of the meanY3-FI and volY3-FI showed superior goodness of fit to Y-FI in Global-FI prediction in all cases and subgroups, with larger coefficients of determination (R2) and smaller root mean square errors. The predicted Global-FI using the regression model of volY3-FI had the best agreement with the measured Global-FI, followed by the meanY3-FI, both showing smaller biases and standard deviation of the percentage difference between predicted- and measured Global-FI than the conventional Y-FI. In addition, the 2 modified assessment tools achieved better interobserver and intraobserver reliabilities than the conventional tool in all cases and subgroups. Conclusion: Two modified assessment tools (meanY3-FI and volY3-FI) were comparable with the Global-FI of the whole supraspinatus muscle, showing stronger correlations with the Global-FI and better predictive performances and reliabilities than the conventional tool (Y-FI). Moreover, the volY3-FI was slightly superior to meanY3-FI in the predictive performance and reliability.

Using Magnetic Resonance Imaging During Childbirth to Demonstrate Fetal Head Moldability and Brain Compression: Prospective Cohort Study.

Childbirth is a physiological process with significant medical risk, given that neurological impairment due to the birthing process can occur at any time. Improvements in risk assessment and anticipatory interventions are constantly needed; however, the birthing process is difficult to assess using simple imaging technology because the maternal bony pelvis and fetal skeleton interfere with visualizing the soft tissues. Magnetic resonance imaging (MRI) is a noninvasive technique with no ionizing radiation that can monitor the biomechanics of the birthing process. However, the effective use of this modality requires teamwork and the implementation of the appropriate safeguards to achieve appropriate safety levels. This study describes a clinically effective and safe method to perform real-time MRI during the birthing process. We reported the experience of our team as part of the IMAGINAITRE study protocol (France), which aimed to better understand the biomechanics of childbirth. A total of 27 pregnant women were examined with 3D MRI sequences before going into labor using a 1-Tesla open-field MRI. Of these 27 patients, 7 (26%) subsequently had another set of 3D MRI sequences during the second stage of labor. Volumes of 2D images were transformed into finite element 3D reconstructions. Polygonal meshes for each part of the fetal body were used to study fetal head moldability and brain compression. All 7 observed babies showed a sugarloaf skull deformity and brain compression at the middle strait. The fetus showing the greatest degree of molding and brain shape deformation weighed 4525 g and was born spontaneously but also presented with a low Apgar score. In this case, observable brain shape deformation demonstrated that brain compression had occurred, and it was not necessarily well tolerated by the fetus. Depending on fetal head moldability, these observations suggest that cephalopelvic disproportion can result in either obstructed labor or major fetal head molding with brain compression. This study suggests the presence of skull moldability as a confounding factor explaining why MRI, even with the best precision to measure radiological landmarks, fails to accurately predict the modality of childbirth. This introduces the fetal head compliance criterion as a way to better understand cephalopelvic disproportion mechanisms in obstetrics. MRI might be the best imaging technology by which to explore all combined aspects of cephalopelvic disproportion and achieve a better understanding of the underlying mechanisms of fetal head molding and moldability.

CT Analysis of the Posteromedial Neurovascular Bundle in Patients with End Stage Ankle Arthritis for Planning of Total Ankle Replacement Surgery

Category: Ankle Arthritis; Ankle Introduction/Purpose: Aim of this study is to identify reliable anatomical landmarks of the posterior tibial neurovascular bundle during Total Ankle Replacement (TAR) to minimise the risk of iatrogenic injury. Secondary aim is to identify if there is associated translation of the bundle when anterior translation of the talus is present. Methods: A radiological landmark protocol was devised to create a consistent method for measuring the relations of the bundle to the tibia, talus and medial gutter line when measured at levels mimicking those of resection undertaken in TAR. Analysis between patients with and without anterior subluxation was undertaken. Results: Total of 42 ankles were reviewed with 38% patient having anterior translation of the talus. At the tibiotalar joint, the bundle lies less than 5mm lateral to the medial gutter line and less than 8mm posterior to the posterior tibia. The same measurements at 10mm superior to the tibiotalar joint are less than 8mm and less than 6.5mm respectively. At 5mm distal to the dome of the talus, the bundle is less than 4mm lateral to the medial gutter line and between 8.4-16.0mm posterior to the posterior talus. The bundle to posterior tibia distance does not increase in the sagittal plane for patients with anterior subluxation of the talus. Conclusion: This study provides relevant guidance for surgeons to use intraoperatively when undertaking tibial and talus resections in TAR to identify their relations to the vulnerable neurovascular structures. The measurements of this study indicate for the first time that there is not an increased risk of iatrogenic injury during bone resection at the tibia in patients with anterior subluxation of the talus.

A computed tomography assessment of olfactory fossa depth in relation to Functional endoscopic sinus surgery in a South African population

IntroductionThe olfactory fossa is a region of the anterior skull base vulnerable to injury during Functional endoscopic sinus surgery, being at the highest risk if deep or asymmetric. Detailed knowledge and preoperative evaluation of olfactory fossa depth and its anatomical variations are vital to avoid iatrogenic injury and resultant complications, in order to perform successful endoscopic surgery. The present study aimed to explore the depth of the olfactory fossa and its associated variations within a South African population. Materials and methodsEighty-six olfactory fossae were assessed using computed tomography scans. Depth measurements were taken on coronal images using predefined radiological landmarks before classification using the Keros system (Types I-III). ResultsThe overall median (Q1–Q3) olfactory fossa depth was 5.75 (4.30–6.50) mm, with statistically significant differences identified according to sex (p = 0.023) and laterality (p = 0.037). Keros Type II was noted most frequently (75.6% of cases), followed by Keros Type I (16.3% of cases). Keros Type III was noted least frequently (8.1% of cases). ConclusionsThe Keros classification is of great importance during preoperative assessments of olfactory fossa depth because of the objective, reliable and pre-emptive information it provides. The South African population displays a higher risk of olfactory fossa injury as a result of the deeper olfactory fossae observed in females (compared to females of other populations), on the left side (compared to the left side of other populations), and overall (entire sample compared to other populations).

Accuracy of Catheter Positioning during Left Subclavian Venous Access: A Randomized Comparison between Radiological and Topographical Landmarks.

Left subclavian venous access increases the risk of vascular damage and thrombosis based on the catheter course and location of the catheter tip. We investigated the accuracy of tip positioning with conventional landmarks using transesophageal echocardiography. The carina as a radiological landmark and the right third intercostal space as a topographical landmark were selected for tip positioning within the target zone, defined as 2 cm above and 1 cm below the right atrial junction. A total of 120 participants were randomized into two groups. The catheter insertion depth was determined as 1.5 cm more than the distance between the venous insertion point and the carina via the right first intercostal space in the radiological group, and between the venous insertion point and the right third intercostal space via the right first intercostal space in the topographical group. The determined insertion depth and actual distance to the right atrial junction of the radiological and topographical groups were 19.5 cm and 20.5 cm, and 19.8 cm and 20.4 cm, respectively. Acceptable positioning was more frequent in the topographical group (96.4% vs. 85.7%; p = 0.047). The catheter tip is more accurately positioned in the distal superior vena cava using topographical landmarks than radiological landmarks.

Is There a Difference in Femur Length Between Neglected Developmental Dysplasia of The Hip (DDH) And Contralateral Normal Hip-Femur Length?: A Radiographic Study

Background and Aim: There are several anatomical problems with the hip joint that are associated with developmental dysplasia (DDH), such as the femoral head being out of place in relation to the acetabulum. First-born status, female sex, a positive family history, breech presentation, and oligohydramnios are all risk factors for preterm labor and birth. DDH severity has been graded using a variety of classification systems, including the Crowe classification, the Hartofilakidis classification, and the Eftekhar and Kerboul classification. The purpose of this study was to determine whether there is a difference in femur length between patients with neglected developmental dysplasia of the hip (DDH) and the normal femur. Materials And Methods: This is a case series study of 14 patients with Unilateral DDH who did not have surgery. Between January 2017 and December 2020, data were retrieved and obtained from our hospital’s picture archiving and communication system (P.A.C.S). A Pelvis x-ray and a Full-Length Femur x-ray were taken for those patients. As a radiological landmark, a fulllength film from the tip of the greater trochanter to the intercondylar space was used in this study. The following were the inclusion criteria: 1. The patient must be an adult who is at least 18 years old. 2. The deformity should only occur on one side (Unilateral DDH). 3. They had never had surgery before. 4. Crowe types III and IV Results: The mean age of the patients was 34 (SD 12.4) years, with females outnumbering males (71.4 % vs 28.6 %). Additionally, the mean length of the affected femur was 41.6 (SD 3.88) and the mean length of the normal femur was 42.2. (SD 4.08). When we compared the baseline characteristics of patients by age group (35 years vs 35 years), we discovered that the BMI of the older age group (35 years) was statistically significantly higher than the younger age group (35 years) (P-value =0.028) Conclusion: As a result of our study, we found an approximately 1 to 2 cm difference in femur length between patients with unilateral DDH and normal hip, which was correlated with age and body mass index (BMI). Preoperative considerations for unilateral DDH include taking a long film of both femurs to determine their relative length differences. This will assist in determining the amount of subtrochanteric femoral osteotomy to perform.

Ultrasound Guided Catheter Tip Location in Neonates: A Prospective Cohort Study

To assess point-of-care-ultrasound (POCUS) guided catheter tip location in a neonatal cohort after insertion of percutaneously inserted central catheters (PICCs) from the upper part of the body. This was a prospective, observational study on PICC tip location. Tip site was assessed by radiological landmarks or direct ultrasound (US) visualization of the cardiovascular structures. One hundred eighteen PICCs (28Gauge/1French) were studied in 102 neonates (mean postmenstrual age 31weeks, range 25-43weeks; mean weight at positioning 1365g, range 420-4180g). Feasibility of POCUS guided tip location was 92.3% in our population. Failures were significantly associated with mechanical ventilation (aOR 5.33; 95% CI 1.13-29.5; P=.038). Agreement between US and radiographic methods was found in 88 of 109 cases (80.7%). Fifteen of 21 discordant cases led to a change in clinical management. POCUS guided localization of small bore PICC is a non-invasive and effective alternative to the conventional radiogram. The latter should be recommended when US examination fails to locate the catheter tip.

Evaluation of the implementation of the sigmoid take-off landmark in the Netherlands.

The sigmoid take-off (STO), the point on imaging where the sigmoid sweeps ventral from the sacrum, was chosen as the definition of the rectum during an international Delphi consensus meeting and has been incorporated into the Dutch guidelines since October 2019. The aim of this study was to evaluate the implementation of this landmark 1year after the guideline implementation and to perform a quality assessment of the STO training. Dutch radiologists, surgeons, surgical residents, interns, PhD students and physician assistants were asked to complete a survey and classify 20 tumours on MRI as 'below', 'on' or 'above' the STO. Outcomes were agreement with the expert reference, inter-rater variability and accuracy before and after the training. Eighty-six collaborators participated. Six radiologists (32%) and 11 surgeons (73%) used the STO as the standard landmark to distinguish between rectal and sigmoidal tumours during multidisciplinary meetings. Overall agreement with the expert reference improved from 53% to 70% (p<0.001) after the training. The positive predictive value for diagnosing rectal tumours was high before and after the training (92% vs. 90%); the negative predictive value for diagnosing sigmoidal tumours improved from 39% to 63%. Approximately half of the represented hospitals have implemented the new definition of rectal cancer 1year after the implementation of the Dutch national guidelines. Overall baseline agreement with the expert reference and accuracy for the tumours around the STO was low, but improved significantly after training. These results highlight the added value of training in implementation of radiological landmarks to ensure unambiguous assessment.

Posterior reversible encephalopathy syndrome with spinal cord involvement

Posterior reversible encephalopathy syndrome (PRES) is an heterogeneous syndrome with the neurologic symptoms of hypertensive encephalopathy. In the majority of cases has typical MRI radiological landmark corresponding to edema that is classically parieto-occipital. Rare are the form with spinal cord involvement (PRES-SCI).

Prognostic Impact of Muscle Quantity and Quality and Fat Distribution in Diffuse Large B-Cell Lymphoma Patients.

Baseline CT scans of 116 patients (48% female, median 64 years) with diffuse large B-cell lymphoma (DLBCL) were retrospectively reviewed to investigate the prognostic role of sarcopenia and fat compartment distributions on overall survival (OS), progression-free survival (PFS), and early therapy termination. Skeletal muscle index (SMI), skeletal muscle density (SMD), and intermuscular adipose tissue (IMAT) were quantified at the level of the third lumbar vertebra (L3) and proximal thigh (PT). Low L3-SMD, but not low L3-SMI, was associated with early therapy termination (p = 0.028), shorter OS (HR = 6.29; 95% CI = 2.17–18.26; p < 0.001), and shorter PFS (HR = 2.42; 95% CI = 1.26–4.65; p = 0.008). After correction for sex, International Prognostic Index (IPI), BMI, and R-CHOP therapy (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone), low L3-SMD remained associated with poor OS (HR = 3.54; 95% CI = 1.10–11.40; p = 0.034) but not with PFS. Increased PT-IMAT was prognostic for poor OS and PFS after correction for sex, IPI, BMI, and R-CHOP therapy (HR = 1.35; CI = 1.03–1.7; p = 0.03, and HR = 1.30; CI = 1.04–1.64; p = 0.024, respectively). Reduced muscle quality (SMD) and increased intermuscular fat (IMAT), rather than low muscle quantity (SMI), are associated with poor prognosis in DLBCL, when measured at the L3 level, and particularly at the level of the proximal thigh. The proximal thigh represents a novel radiological landmark to study body composition.

Comparison of Peres' Formula and Radiological Landmark Formula for Optimal Depth of Insertion of Right Internal Jugular Venous Catheters.

BackgroundCentral venous catheterization is a vital procedure for volume resuscitation, infusion of drugs, and for central venous pressure monitoring in the perioperative period and intensive care unit (ICU). It is associated with position-related complications like arrhythmia's, thrombosis, tamponade, etc. Several methods are used to calculate the catheter insertion depth so as to prevent these position-related complications.ObjectiveTo compare Peres’ formula and radiological landmark formula for central venous catheter insertion depth through right internal jugular vein (IJV) by the anterior approach.Materials and methodsA total of 102 patients posted for elective cardiac surgery were selected and divided into two equal groups—Peres’ group (group P) and radiological landmark group (group R). Central venous catheterization of right IJV was done under ultrasound (USG) guidance. In group P, central venous catheter insertion depth was calculated as height (cm)/10. In group R, central venous catheter insertion depth was calculated by adding the distances from the puncture point to the right sternoclavicular joint and on chest X-ray the distance from the right sternoclavicular joint to carina. After insertion, the catheter tip position was confirmed using transesophageal echocardiography (TEE) in both the groups.ResultsAbout 49% of the catheters in group P and 74.5% in group R were positioned optimally as confirmed by TEE, which was statistically significant. No complications were observed in both the groups.ConclusionRadiological landmark formula is superior to Peres’ formula for measuring optimal depth of insertion of right internal jugular venous catheter.How to cite this articleManudeep AR, Manjula BP, Dinesh Kumar US. Comparison of Peres’ Formula and Radiological Landmark Formula for Optimal Depth of Insertion of Right Internal Jugular Venous Catheters. Indian J Crit Care Med 2020; 24(7):527–530.

Carpal Collapse After Scaphoid Nonunion: A Novel Combined Approach to the 1,2 Intercompartmental Supraretinacular Artery Radial Flap

PurposeScaphoid nonunion remains a major problem in hand surgery. The 1,2 intercompartmental supraretinacular artery flap (1,2 ICSRA), as first described by Zaidemberg et al, is widely used with reported union rates of approximately 80%. However, its use is limited in the case of associated carpal collapse as in dorsal intercalated segmental instability (DISI) and humpback deformity. In this study, we present a novel approach to this flap enabling the correction of associated carpal collapse.MethodsBetween 2006 and 2015, 9 patients with scaphoid nonunion or delayed union with carpal collapse were treated with a vascularized bone flap based on the 1,2 ICSRA using a combined volar and dorsal approach. Immobilization in a short-arm cast was applied for 8 weeks. Union rates, correction of DISI and humpback deformity, as well as clinical end points were noted. In addition, scapholunate (SL) angles were measured using 2 accepted radiological techniques, employing either the scaphoid midline axis or its proximal radiological landmarks as a reference.ResultsAll cases united and a median time to bone consolidation of 4 months (range, 2–5 months) was observed. Preoperative DISI deformities (n = 4) were corrected in all patients. Humpback deformities (n = 5) were also corrected. Two patients had repeat surgery: one for K-wire removal after bony consolidation and the other for neuropathic pain.ConclusionsThe 1,2 ICSRA bone flap is a reliable treatment for scaphoid nonunion associated with carpal collapse. This combined volar and dorsal approach permits the correction of DISI and humpback deformity without compromising the scaphoid vascular supply, which eliminates the need to use free bone flaps from other sites. In this series, we observed a 100% union rate. Two patients required reoperation for symptomatic hardware and dorsal wrist pain linked to superficial neuritis.Type of study/level of evidenceTherapeutic IV.

Hybrid percutaneous technique guided by ultrasound and fluoroscopy: anatomical bases for sensitive glenohumeral joint neuroablative denervation

IntroductionSince John Hilton (1873), an anatomist physician and British surgeon, joint sensitive innervation had been studied. Understanding this anatomy allows neuroablative joint denervation (NJD) through percutaneous access to the treatment of joint pain in cases of osteoarthritis and shoulder capsulitis, for examples. The shoulder has a rich sensory innervation from mixed nerves, with motor components. Thus, for the NJD the approach should be guided to the sensitive branches of the nerves, avoiding motor sequelae. Suprascapular (SSN), axillary (AN) and lateral pectoral (PLN) nerves are responsible for 98% of sensory innervation of the glenohumeral joint, then represent the most important anatomical target in NDJ procedure.ObjectiveThe aim of this study is to show the anatomical and radiological landmarks for NDJ procedure.Method Dissection of SSN, AN and PLN nerves sensitive branches. Definition of anatomical landmarks of SSN, AN and PLN nerves sensitive branches, by fluoroscopy (FC) and ultrasound (US). NJD was performed on the glenohumeral joint of 8 patients, by cooled radiofrequency (CRF), through percutaneous anatomical accesses using hybrid technique, guided by US and the positioning of the cannulas by bone anatomical references were confirmed by FC. The 8 patients presented joint pain without muscle or tendinous components and without indication of surgical therapy. The visual analogue scale (VAS) and shoulder disability index test were applied before and after the procedure during 6 months. (Figure 1, 2)ResultsThe dissection of SSN, AN and PLN nerves sensitive branches showed the anatomical topography of the sensitive area of the glenohumeral joint innervation. Those anatomical information supported the NDJ procedure in all the 8 patients, were performed feasible and safely, using the hybrid technique (FC and US).Discussion and ConclusionSupported by the anatomical results, the steps of the NDJ procedure were established. The SSN, after passing through the spinoglenoid notch, sends laterally articular sensory branches. Thus, guided by US, the needle tip was placed at the lateral extreme point from the glenoid notch without joint or labrum injury. The AN sends sensory branches after passing through the greater tuberosity inferior margin of the humerus, accessed by US locating the tip of the needle cranially to the posterior humeral circumflex artery and touching the humerus laterally. The PLN sensitive branches go through the caudal and lateral region of the coracoid process, and this area is identified for US guided cannula position. After the cannulas were located, their position was checked by FC, using the bone as reference, and some adjustments could be performed, if necessary. Sensory innervation was properly accessed and NJD procedure was performed without motor innervation damages. Knowledge of anatomical landmarks recognized by dissection or by radiographic or dynamic images such as ultrasound, when combined, can present themselves as tools that contribute to increasing the effectiveness and safety of clinical procedures.Support or Funding Information www.mobissom.com.brA, B, C, D ‐ Suprascapular nerve (SSN); E, F, G, H – Axillary nerve (AN); I, J, K ‐ Lateral pectoral nerve (PL). C, G, J – Ultrasound; D, H, K ‐ Fluoroscopy.1. SSN; 2. M. Infraspinatus1. SSN; 3. Fossa supraspinata; 4. Fossa infraspinataYellow arrow – SSNE. 1. AN (anterior view)F. 1. AN (posterior view); 2. Sensitive branch of ANG. Yellow arrow – NAI. 1. M. pectoralis major; 2. M. pectoralis minor; 3. PL; 4. Sensitive branch of PL.J. Yellow arrow – PLFigure 1Ultrasound.Figure 2

A Comparison of the external anatomical landmark and the radiological landmark for obtaining the optimal depth of a right internal jugular venous catheter in pediatric cardiac patients

The external anatomical landmark and the radiological landmark have been introduced to provide estimation of the depth of right internal jugular venous catheter during insertion. This study aimed to compare the accuracy, agreement, and reliability of the external anatomical landmarkand the radiological landmark, confirmation being by transesophageal echocardiography. This prospective observational study was conducted in children ages 1-15years. The catheter was placed at the superior vena cava and the right atrium junction guided by transesophageal echocardiography. The catheter depth derived from the transesophageal echocardiography, the external anatomical landmark, and the radiological landmark was recorded. The optimal zone of the catheter tip was 5mm below and 10mm above the superior vena cava and the right atrium junction. Accuracy was assessed by the difference between the transesophageal echocardiography and the external anatomical landmark or the radiological landmark. Agreement with Bland-Altman plots and correlation were tested. Eighty participants, median age of 3years, were enrolled. The median (IQR) differences between the depth of the transesophageal echocardiography and the external anatomical landmark or the radiological landmark were 0.30 (0, 0.70) and 0.10 (-0.20, 0.90) cm, respectively. Bland-Altman plots demonstrated good agreement between the depths. The catheter tips were located in the optimal zone more frequently with the external anatomical landmark than the radiological landmark (94.7% vs 64.5%). The external anatomical landmark showed a stronger correlation to transesophageal echocardiography than the radiological landmark (r=.95 vs .83). Both the external anatomical landmark and the radiological landmark enabled accurate estimation of the central venous catheter depth close to the superior vena cava and the right atrium junction. The external anatomical landmark is of more potential use than the radiological landmark in clinical practice.