A new species of free-living marine nematode, Diplolaimella ariakensis n. sp. (Nematoda: Monhysteridae) from the Ariake Sea, Japan

Summary A new species of free-living marine nematode, Diplolaimella ariakensis n. sp., is described from a muddy tidal flat of the Ariake Sea, southern Japan. Diplolaimella ariakensis n. sp. differs from its congeners by the following: presence of ocelli, absence of denticles in the buccal cavity, a long tail (11-14 cloacal body diam., c = 3.2-4.0 in male, 17-21 anal body diam., c = 2.9-3.4 in female), spicules as long as 1.4-1.8 cloacal body diam., gubernaculum 0.4-0.5 cloacal body diam. long with a dorsocaudal apophysis 0.5-0.7 cloacal body diam. long, presence of a precloacal supplement, absence of postcloacal papillae, presence of seven pairs of body pores in male, and the anterior position of the vulva (V = 43-46). A dichotomous key to Diplolaimella species is provided. Almost full-length 18S rRNA and partial cytochrome c oxidase subunit I gene sequences were determined for D. ariakensis n. sp. A maximum likelihood tree of 18S sequences supported a close relationship between D. ariakensis n. sp. and D. dievengatensis.

Biomechanical consequences of tibial tubercle osteotomy in a 3D-printed model of patellofemoral dysplasia (207)

Objectives: Trochlear dysplasia and an increased tibial tubercle-trochlear groove (TT-TG) distance are two major contributing factors to patellar instability and are often found concurrently. Patellar morphology is also abnormal in the setting of trochlear dysplasia. Indications for tibial tubercle osteotomy (TTO) include recurrent patellar instability in the setting of an increased TT-TG distance. While anteromedialization (AMZ) TTO has been shown to decrease overall PF contact stresses and improve patellar tracking, this has never been demonstrated in a model of PF dysplasia. Due in part to a lack of available dysplastic cadaveric specimens, few studies have investigated the consequences of PF dysplasia on PF biomechanics. Our previous work has demonstrated that when compared to normal morphology, PF dysplasia results in a lateral shift but negligible increases in patellar contact forces. This prompted the question of how TTO affects contact mechanics in this setting. The objective of this study was to quantify contact mechanics and kinematics following TTO using a 3D-printed PF dysplasia model. We hypothesized that an anterior tubercle position simulating AMZ TTO would best improve PF contact mechanics. Methods: Five fresh frozen cadaveric knees were dissected free of all soft tissues except the extensor mechanism. Computed tomography (CT) scan of each specimen confirmed no trochlear dysplasia or patella alta and a normal TT-TG distance (<10 mm). Dysplastic bone geometries were derived from patient CT scans selected by the senior orthopaedic surgeon who specializes in PF surgery. Segmentation was performed using Mimics (Materialise Figure 1A&B). Cadaveric knees were grouped based on the medial and lateral epicondylar distance (ML distance), and the implants were scaled to the size of each group. Scaling was done using Geomagic Studio (3D Systems), and implants were printed using a Form2 SLA 3D printer (Formlabs). Durable resin (Formlabs) was used to minimize wear between the printed components (Figure 1C). Cadaveric bony resection was performed using Biomet Vanguard (Zimmer Biomet) equipment. The amount of bone resected matched the 3D implant dimensions. A 6° distal femoral valgus cut angle was utilized. For femoral rotation, posterior referencing was utilized (no lateral insufficiency was observed), and cuts were made with 3° of external rotation in relation to the transepicondylar axis. The 3D implant was then fixed flush to the distal femur and native trochlea using screws. A metered patellar reamer was used for patellar preparation. The patellar implant was pressed into a central peg hole and fixed with a screw placed through the anterior patella. A flat tibial tubercle osteotomy cut, matching the aforementioned femoral rotation, was made with a shingle thickness of 1 cm and length of 6 cm. Each knee was mounted to a custom fixture on a servo-hydraulic load frame (MTS, Eden Prairie, MN) and cycled 5 times from 0° to 70° by pulling on the quadriceps tendon using a pulley system (Figure 1D). The shingle was fixed to the tibia using two 1.57mm K-wires. For each specimen, testing was repeated for each of three tibial tubercle positions: Native tubercle position (“normal”), 1 cm lateral to native (“lateral”), and 1 cm anterior to native (“anterior”) (Figure 2A-C). For the anterior position, a 1 cm thick plastic bone block was placed between the shingle and the tibia while maintaining its native position in the coronal plane. The lateral position was intended to represent the presurgical pathologic state (increased TT-TG), the native position a postsurgical medialized state, and the anterior position a postsurgical anteromedialized state. PF contact pressures were recorded using an electronic pressure sensor (sensor #5040, Tekscan, Boston, MA). Contact data was separated to the medial and lateral facets by identifying the median patellar ridge on the sensor. Within each facet, the sum of forces and center of pressure (weighted average of position of all acting forces within the facet relative to the median patellar ridge) was computed. Kinematics were recorded using a reflective marker motion capture system (Cortex, Motion Analysis Corporation, Santa Rosa, CA). Repeated measures ANOVA with post hoc Bonferroni analysis was used to determine differences in contact force and center of pressure location for each tubercle position. Statistical significance was defined as p<0.05. Results: There was a significant increase in the lateral facet, medial facet, and total patellar contact forces with lateral tubercle position compared to the anterior position (Figure 3). There was also a significant increase in medial facet and total patellar contact forces with the native tubercle position compared to the anterior position. There were no significant differences in lateral facet, medial facet, or total patellar contact forces when comparing the native and lateral tubercle positions. There was a trend toward an increased (lateralized) lateral facet center of pressure when comparing the lateral and anterior tubercle positions (Figure 4). Conclusions: Using a model capable of quantifying kinematics and contact mechanics for dysplastic trochleae and patellae, we demonstrated that an anterior tubercle position resulted in decreased patellar contact forces when compared to lateralized and native tubercle positions. These findings suggest that when an AMZ TTO is performed in the setting of an increased TT-TG distance and PF dysplasia, overall patellar contact forces are reduced. This may improve PF biomechanics and potentially decrease the likelihood of future PF OA. Similar findings were not observed for the native tubercle position, suggesting that anterorization is a critical consideration in improving PF biomechanics in this setting.

LATERAL PEG-SHAPED INCISIVE AESTHETIC TREATMENT WITH INDIRECT VENEER RESTORATION USING CERAMO POLYMER RESTORATION

Peg shape is one of the abnormalities of dental anatomy, i.e. tooth size is smaller than average and tapered shape. These peg-shaped teeth are often found in the maxillary lateral incisors and third molars. The form on the lateral incisor often causes aesthetic problems because of its anterior position. One of the treatments for peg-shaped teeth is Veneer. Case report: 26 years old woman had a peg-shaped shape on both lateral incisors. Indirect veneer aesthetic treatment was performed using Ceramage to correct the form and cover the diastema to achieve better aesthetics. Wax-up is done to see the suitability of the shape and proportion of the Veneer. Patients get a visual picture of the expected treatment results. The treatment results in Ceramage gave an excellent condition in improving the shape of the Peg-shaped incisor. The veneer colour resembles natural teeth, and the patient is satisfied with the treatment results. Ceramage can be used as a treatment option for anterior teeth with deformities. Ceramage Veneer is an alternative that can be done to improve the aesthetic appearance at a more economical cost for anterior teeth.

The Risk Factors Anesthesiologists should Pay Attention for Massive Bleeding in Placenta Accreta Spectrum Patients with Placenta Previa During Surgery: A Retrospective Study

Objectives: PAS combined with placenta previa exists as a high-risk factor for postpartum hemorrhage. The risk factors for predicting a certain disease may be different from the risk factors for massive bleeding during surgery for the disease. To explore whether the risk factors of massive bleeding in patients with Placenta accreta spectrum (PAS) with placenta previa underwent Cesarean section under the background of abdominal aortic balloon occlusion will be changed.Methods: We reviewed 267 singleton pregnancies with PAS and placenta previa. Maternal history, antenatal ultrasound findings of the placenta, placement of the abdominal aortic balloon were reviewed retrospectively, and their association with massive bleeding during Cesarean section was analyzed.Results: Multivariate Logistic regression analysis revealed that the number of pregnancies (odds ratio (OR), 2.680; 95% CI, 1.244–5.774), placenta location (anterior position) (OR, 3.172; 95% CI, 1.349–7.458) and cervical length (OR, 0.918; 95% CI, 0.854–0.987), implant area (OR, 1.018; 95% CI, 1.009–1.027)，abdominal aorta balloon inflation (OR, 0.278; 95% CI, 0.095–0.813) were associated with massive bleeding (>1000 mL).Conclusions: Abdominal aorta balloon inflation may change the known risk factors for hemorrhage. The number of pregnancies, placenta location (anterior position), cervical length, implant area, abdominal aorta balloon inflation are risk factors for massive bleeding during Cesarean section in cases of PAS and placenta previa. Balloon occlusion of the abdominal aorta can indeed reduce the risk of massive bleeding.

A new species of a rare genus, Truxonchus quangi sp. n. (Mononchida, Anatonchidae) from bat xat nature reserve in Lao Cai Province, Vietnam

Truxonchus quangi sp. n. is described and illustrated from Vietnam. Females of the new species are characterized by large body size (L = 4.8-5.8 mm); barrel shaped buccal cavity of large size (105-113 x 66-73 µm) with one dorsal tooth and two subventral teeth posteriorly directed, of equal shape, size and apex position; dorsal tooth apex located 36-39% of buccal cavity length from its base; reproductive system didelphic-amphidelphic, vagina long, 39-45% of corresponding body width, with distinct par refringens vaginae, sclerotized pieces rounded in optical section; tail long, filiform, ventrally arcuate, with three small caudal glands in tandem and prominent subventral spinneret. The new species is close to T. dolichurus but differs by the larger buccal cavity, more anterior position of the dorsal tooth apex, more anterior vulval position and presence of advulval pores.

Introduction and reproducibility of an updated practical grading system for lumbar foraminal stenosis based on high-resolution MR imaging

In this paper we sought to develop and assess the reproducibility of an updated 6-point grading system for lumbar foraminal stenosis based on the widely used Lee classification that more accurately describes lumbar foraminal stenosis as seen on high-resolution MRI. Grade A indicates absence of foraminal stenosis. Grades B, C, D and E indicate presence of foraminal stenosis with contact of the nerve root with surrounding anatomical structures (on one, two, three or four sides for B, C, D and E respectively) yet without morphological change of the nerve root. To each grade, a number code indicating the location of contact between the nerve root and surrounding anatomical structure(s) is appended. 1, 2, 3 and 4 indicate contact of the nerve root at superior, posterior, inferior and anterior position of the borders of the lumbar foramen. Grade F indicates presence of foraminal stenosis with morphological change of the nerve root. Three readers graded the lumbar foramina of 101 consecutive patients using high-resolution T2w (and T1w) MR images with a spatial resolution of beyond 0.5 mm3. Interreader agreement was excellent (Cohen’s Kappa = 0.866–1). Importantly, 30.6%/31.6%/32.2% (reader 1/reader 2/ reader 3) of foramina were assigned grades that did not appear in the original Lee grading system (grades B and D). The readers found no foramen that could not be described accurately with the updated grading system. Thus, an updated 6-point grading system for lumbar foraminal stenosis is reproducible and comprehensively describes lumbar foraminal stenosis as seen on high-resolution MRI.

Anterior position of dispersive patch for esophageal protection during atrial fibrillation ablation. A pilot feasibility study

Funding Acknowledgements Type of funding sources: None. Introduction Ablation for atrial fibrillation (AF) carries a significant risk of esophageal injury. Current methods of esophageal protection are invasive, expensive and their cost-effectiveness can be questioned. Standard placement of dispersive patch (DP) at patient’s back exposes esophagus to radio-frequency (RF) current-mediated thermal injury and such complications as esophageal wall ulceration, peri-esophageal injury or life-threatening atrio-esophageal fistula. Redirecting RF current by DP repositioning to anterior chest can theoretically protect oesophagus from thermal injury, however, such an approach has not yet been investigated. Aim To determine feasibility of anterior DP position for treatment of AF using RF catheter ablation (RFCA)-based system. Methods We retrospectively analysed consecutive patients undergoing RFCA-based pulmonary vein isolation (PVI) using multi-electrode PVAC catheter with DP located either in anterior or traditional-posterior position. Two additional patients underwent point-by-point RFCA and mapping of PV ostia with impedance measurements during RFCA performed using anterior and posterior DP positioning. Results 62 patients (25 females, age 60 ± 12 years) underwent PVI using PVAC: 40 patients in posterior and 22 in anterior DP group. There were no major complications during procedures. There was no significant difference in AF recurrence rate between anterior and posterior DP groups during one-year follow up (log rank p = 0.065). In two additional consecutive patients (1 female, age 74 ± 2 years) undergoing point-by-point RFCA a total number of 30 measurements around PV ostia were performed. There was a significant difference between impedance values in anterior vs posterior DP positions (134 ± 7 Ω vs 122 ± 8 Ω, p = 0.0004). Conclusions Anterior position of dispersive electrode for PV isolation using RFCA-based systems is safe, feasible, atraumatic and is not associated with any additional cost. Apart from redirecting RF current away from the esophagus, anterior dispersive patch placement is associated with higher impedance values which can act as an additional protection. Possible prevention of esophageal complications using anterior dispersive patch positioning needs to be determined in prospective studies. Abstract Figure. AF-free survival and impedance

Uncal apex movement and positioning in Alzheimer's Disease

Alzheimer’s Disease (AD) patients have consistently shown declines in declarative memory, consolidation, and in many other cognitive areas. These changes are associated with atrophy and volumetric declines in medial temporal lobe structures, such as the hippocampus. Hippocampal atrophy has been associated with AD. However, the influence of AD atrophy on the position of the uncal apex—an anatomical landmark for the hippocampus—has not been longitudinally examined. The current study’s objective is to investigate changes in the position of the uncal apex of AD patients over the course of two years. The current study draws upon the Alzheimer’s Disease Neuroimaging Initiative (ADNI) data set (adni.loni.usc.edu). For each participant, I obtained demographic data, anatomical MRI images in native space, hippocampal segmentations from the subcortical stream of FreeSurfer (v.5.3.0), and linear transforms to MNI space. Using uncal apex y-positions transformed in MNI space, I found that the uncal apex fell in a more posterior position in AD patients relative to control and that over time, the uncal apex migrates toward a more anterior position in both groups. These results suggest that part of the neuroimaging examinations that are done on AD patients should examine uncal apex positions as a biomarker of early AD progression. Future directions and limitations are discussed

Evaluation and management of obstetric genital fistulas treated at a pelvic floor centre in Germany

Background Obstetric genital fistulas are an uncommon condition in developed countries. We evaluated their causes and management in women treated at a German pelvic floor centre. Methods Women who had undergone surgery for obstetric genital fistulas between January 2006 and June 2020 were identified, and their records were reviewed retrospectively. Results Eleven out of 40 women presented with genitourinary fistulas, and 29 suffered from rectovaginal fistulas. In our cohort, genitourinary fistulas were more common in multiparous women (9/11), and rectovaginal fistulas were more common in primiparous women (24/29). The majority of the genitourinary fistulas were at a high anterior position in the vagina, and all rectovaginal fistulas were at a low posterior position. While all genitourinary fistulas were successfully closed, rectovaginal fistula closure was achieved in 88.65% of cases. Women who suffered from rectovaginal fistulas and were at high risk of recurrence or postoperative functional discomfort and desired another child, we recommended fistula repair in the context of a subsequent delivery. For the first time, pregnancy-related changes in the vaginal wall were used to optimize the success rate of fistula closure. Conclusions In developed countries, birth itself can lead to injury-related genital fistulas. As fistula repair lacks evidence-based guidance, management must be tailored to the underlying pathology and the surgeon’s experience. Attention should be directed towards preventive obstetric practice and adequate perinatal and postpartum care. Although vesicovaginal fistulas occur rarely, in case of urinary incontinence after delivery, attention should be paid to the patient, and a vesicovaginal fistula should be ruled out. Trial registration Retrospectively registered, DRKS 00022543, 28.07.2020.