Challenging Lesions Research Articles

Directional atherectomy with antirestenotic therapy for the treatment of no-stenting zones.

Endovascular treatment for peripheral artery occlusive disease carries unresolved problem of restenosis. Treatment modalities in areas of high mechanical stress like popliteal artery and common femoral artery remains challenging. New-generation devices improved the results of stent therapy in this anatomical territory, but could impact on future surgical options if they are needed. Vessel preparation prior to drug (paclitaxel)-coated balloons (DCB) angioplasty leads to better paclitaxel penetration into the arterial wall and improved drug uptake. The "leave nothing behind" strategies, DCB angioplasty and combined directional atherectomy (DA) and antirestenotic therapy (DAART), can theoretically overcome the problems caused by the mobility of the knee joint. However, calcified and longer lesions remain a challenging subset that is less responsive to DCBs, resulting in higher provisional stent rates. For the treatment of long and calcified femoropopliteal lesions, vessel preparation with DA before DCB angioplasty seems to be safe in mid-term follow-up and might have benefits in more challenging lesion subsets that are at higher risk for acute and chronic technical treatment failure of percutaneous transluminal angioplasty, including DCB angioplasty, such as severely calcified lesions. Treatment with DA+DCB resulted in both increased technical success and fewer flow-limiting dissections compared with treatment with DCB alone. In concept of "leave nothing behind" therapies for isolated popliteal artery lesions, DAART was associated with a higher primary patency rate than DCB angioplasty alone.

Skin Adnexal Tumors in Plain Language: A Practical Approach for the General Surgical Pathologist.

Skin adnexal tumors, those neoplasms deriving from hair follicles and sweat glands, are often a source of confusion amongst even experienced pathologists. Many well-described entities have overlapping features, tumors are often only partially sampled, and many cases do not fit neatly into well-established classification schemes. To simplify categorization of adnexal tumors for the general surgical pathologist and to shed light on many of the diagnostic dilemmas commonly encountered in daily practice. The following review breaks adnexal neoplasms into 3 groups: sebaceous, sweat gland-derived, and follicular. Pathology reference texts and primary literature regarding adnexal tumors. Review of the clinical and histopathologic features of primary cutaneous adnexal tumors, and the diagnostic dilemmas they create, will assist the general surgical pathologist in diagnosing these often challenging lesions.

Temporal changes in characteristics, treatment strategies, and outcomes of coronary bifurcation lesion interventions.

Coronary bifurcations are common in daily practice of percutaneous coronary intervention and remain one of the most challenging lesions, but it is still unknown how characteristics, treatment strategy, and outcomes have changed over the last decade of drug-eluting stents (DES) era. We evaluated characteristics of treatment pattern and outcomes for patients with bifurcation disease over time in real-world clinical practice. A total of 7282 patients with coronary bifurcation lesions were pooled from the Interventional Cardiology Research Incorporation Society-Drug-Eluting Stents registry and the Interventional Research Incorporation Society-Left MAIN registry. Primary outcome was a target-vessel failure (TVF), defined as a composite of cardiac death, target-vessel myocardial infarction, or clinically indicated target-vessel revascularization. Among the total population, 2232 (30.7%) had left main bifurcation lesions. The use of one-stent strategy was more frequent in conjunction with second-generation DES (86.2 vs. 13.8%) than with first-generation DES (65.4 vs. 34.6%). Two-stent strategy was associated with a higher risk of TVF as compared with one-stent strategy [adjusted hazard ratio (HR): 1.28, 95% confidence interval (CI): 1.12-1.47, P<0.001]. However, the risk of TVF with two-stent strategy relative to one-stent strategy has decreased from the first-generation DES (HR: 1.56, 95% CI: 1.22-1.99, P<0.001) to the second-generation DES (HR: 1.12, 95% CI: 0.94-1.34, P=0.19). For patients with bifurcation disease, stenting strategy has become more simpler and percutaneous coronary intervention outcomes have more improved over time. One-stent strategy relative to two-stent strategy was associated with better clinical outcomes, but the advantage of one-stent strategy was less pronounced with the use of second-generation DES.

Locked posterior fracture-dislocation of the shoulder.

Background and aim of the work: To describe a valid option for the treatment of locked posterior fracture-dislocation of the shoulder (LPFDS) and to compare it to the literature about this topic. Methods: We present a small case series (3 patients), with a medium follow up at 4 years and 5 months. We accurately describe our surgical strategies, underlining the choice of approach, reduction and fixation. Results: The three patients showed excellent functional and radiological results at the follow up examinations, with a full range of shoulder movements and complete regain of pre-trauma activities. A lateral approach (standard or minimally invasive), a reduction technique with a Shantz pin in the head and in the humeral shaft, and fixation with a locking plate were used in the three patients. Conclusion: LPFDS is a challenging lesion, hard to recognize and to treat. Our suggested method of treatment is highly reproducible and has revealed itself to be very effective in achieving good results. (www.actabiomedica.it)

Procedural and follow-up clinical outcomes after chronic total occlusion revascularization: Data from an Indian public hospital

BackgroundChronic total occlusion (CTO) continues to be challenging lesion subset for percutaneous intervention. Last decade has seen tremendous increase in percutaneous coronary intervention (PCI) in this subset owing to improved understanding of the anatomy and enhanced skillset with availability of dedicated hardware. We sought to study the outcomes of CTO PCI in an Indian public hospital. MethodsThis was a single-center non-randomized descriptive follow-up study on CTO PCI. The end-points were procedural success, immediate, and late adverse cardiovascular events [major adverse cardiac event (MACE)] and change in angina and left ventricular function at follow-up. ResultsA total 389 CTO lesions were treated with a success rate of 87% (339/389). The mean Japanese chronic total occlusion (J-CTO) score was 1.78 ± 0.12 (mean ± standard deviation). Multivariate analysis of different angiographic components of J-CTO score identified tortuosity (p = 0.001), calcifications (p ≤ 0.001), and blunt stump (p = 0.007) as independent predictors of procedural failure. The periprocedural mortality was less than 1%, and the non-life threatening complications were about 4%. The MACE rate was significantly higher in the procedural failure group (60%) than in the procedural success group (5.3%, p < 0.001). An increase in left ventricular ejection fraction (LVEF) was noted following successful CTO PCI after complete revascularization. ConclusionsThe success rates for CTO PCI in this registry were about 87%. Immediate and long-term clinical outcomes were better with lower MACE (5%) after a successful procedure. A key outcome variable included an increase in LVEF among patients after a successful CTO PCI. The overall periprocedural complications were about 5.5%, but majority were non-life threatening.

Part I. Infantile Hemangioma: Literature review of current science, classification and management

Infantile hemangioma is the most common benign tumor in infants. These vascular tumors are not usually present at birth but will begin to form within the first 12 weeks after birth, completing growth by 9-12 months of age, then entering into an involutional stage of several years. Tumors vary from very small, non-invasive to large tumors that cause disfigurement and depending upon location, functional compromise. Hemangiomas may not entirely resolve, often times leaving residual tumor or a lipo- fibrotic mass with dermal scarring. Treatment for hemangiomas is varied and may include, but not limited to, observation, surgery, corticosteroids, beta-blockers, and laser therapy. Choice of treatment is based on size, location, and stage of tumor growth. This review article is presented in two parts: Part I- a comprehensive literature review of the current science of the biology of hemangioma formation, classification schemes, and management. Part II follows with our institutional review of the management of these sometimes challenging lesions of childhood. (Part I will be published in the 2nd Quarter edition of the WVMJ.)

Who Should Carry Out Skin Cancer Excisions? A Systematic Review.

Background:The incidence of melanoma and nonmelanoma skin cancers is increasing in the United Kingdom. Surgical excision carries the highest cure rates for all skin cancers and is the first-line treatment for melanomas and high-risk nonmelanoma cancers. This is most commonly performed by general practitioners (GPs), dermatologists, and plastic surgeons.Objective:The aim of this study was to identify which health-care professionals achieve the best outcomes following surgical excision of skin cancer lesions.Materials and Methods:A comprehensive search of the Cochrane Library and PubMed databases was conducted. PRISMA guidelines were adhered to throughout.Results:Six studies were identified and reviewed. Dermatologists were most likely to excise lesions adequately, and GPs were the least likely. Dermatologists displayed the greatest diagnostic accuracy, and excisions led by them had the highest overall and disease-free survival rates. Plastic surgeons were most likely to excise complex lesions on difficult-to-treat areas.Conclusion:Dermatologists can excise many skin lesions adequately, but plastic surgeons should continue to take an active role in complex or anatomically challenging lesions. There is a need for more validated training for GPs in the management of skin cancers. Further studies incorporating a randomized control protocol are needed to definitely assess who is best placed to surgically excise these lesions.

Meningiomas Originated at the Falcotentorial Region: Analysis of Topographic and Diagnostic Features Guiding an Optimal Surgical Planning

Meningiomas arising at the pineal region are a rare entity and still represent a great neurosurgical challenge given their deep location and critical neuroanatomic relationships. The optimal surgical approach to treat these lesions is still under debate. Our objective is to review the topographic and diagnostic features of these lesions, which can help to guide an optimal surgical outcome. We present 2 clinical cases of falcotentorial meningiomas successfully treated at our institution (2016-2017) with different surgical approaches. A literature review is performed, and a description of the classification, anatomic relationships, clinical features, diagnosis, and different surgical options and outcomes of these lesions is presented. The first patient was treated via a supracerebellar infratentorial approach, and the second patient was treated via a parieto-occipital interhemispheric approach. In both tumors, a gross total resection was achieved with no permanent neurologic deficits. In the literature review, gross total resection rates range from 33% to 100%, with no differences regarding the type of meningioma or the surgical approach performed. Permanent neurologic morbidity varies from 0% to 50%, and mortality rates range from 0% to 23%. The distortion and displacement of the vein of Galen and straight sinus represent the most important feature in the decision of optimal surgical approach. Pineal region meningiomas represent very infrequent, challenging lesions, and their description in the literature is scarce. The systematic topographic classification of these tumors and evaluation of the neuroanatomic structures involved are crucial to guide a safe and optimal surgical approach and achieve satisfactory outcomes.

Optical coherence tomography for diagnosing skin cancer in adults.

Early accurate detection of all skin cancer types is essential to guide appropriate management and to improve morbidity and survival. Melanoma and squamous cell carcinoma (SCC) are high-risk skin cancers, which have the potential to metastasise and ultimately lead to death, whereas basal cell carcinoma (BCC) is usually localised, with potential to infiltrate and damage surrounding tissue. Anxiety around missing early cases needs to be balanced against inappropriate referral and unnecessary excision of benign lesions. Optical coherence tomography (OCT) is a microscopic imaging technique, which magnifies the surface of a skin lesion using near-infrared light. Used in conjunction with clinical or dermoscopic examination of suspected skin cancer, or both, OCT may offer additional diagnostic information compared to other technologies. To determine the diagnostic accuracy of OCT for the detection of cutaneous invasive melanoma and atypical intraepidermal melanocytic variants, basal cell carcinoma (BCC), or cutaneous squamous cell carcinoma (cSCC) in adults. We undertook a comprehensive search of the following databases from inception up to August 2016: Cochrane Central Register of Controlled Trials; MEDLINE; Embase; CINAHL; CPCI; Zetoc; Science Citation Index; US National Institutes of Health Ongoing Trials Register; NIHR Clinical Research Network Portfolio Database; and the World Health Organization International Clinical Trials Registry Platform. We studied reference lists and published systematic review articles. We included studies of any design evaluating OCT in adults with lesions suspicious for invasive melanoma and atypical intraepidermal melanocytic variants, BCC or cSCC, compared with a reference standard of histological confirmation or clinical follow-up. Two review authors independently extracted data using a standardised data extraction and quality assessment form (based on QUADAS-2). Our unit of analysis was lesions. Where possible, we estimated summary sensitivities and specificities using the bivariate hierarchical model. We included five studies with 529 cutaneous lesions (282 malignant lesions) providing nine datasets for OCT, two for visual inspection alone, and two for visual inspection plus dermoscopy. Studies were of moderate to unclear quality, using data-driven thresholds for test positivity and giving poor accounts of reference standard interpretation and blinding. Studies may not have been representative of populations eligible for OCT in practice, for example due to high disease prevalence in study populations, and may not have reflected how OCT is used in practice, for example by using previously acquired OCT images.It was not possible to make summary statements regarding accuracy of detection of melanoma or of cSCC because of the paucity of studies, small sample sizes, and for melanoma differences in the OCT technologies used (high-definition versus conventional resolution OCT), and differences in the degree of testing performed prior to OCT (i.e. visual inspection alone or visual inspection plus dermoscopy).Pooled data from two studies using conventional swept-source OCT alongside visual inspection and dermoscopy for the detection of BCC estimated the sensitivity of OCT as 95% (95% confidence interval (CI) 91% to 97%) and specificity of 77% (95% CI 69% to 83%).When applied to a hypothetical population of 1000 lesions at the mean observed BCC prevalence of 60%, OCT would miss 31 BCCs (91 fewer than would be missed by visual inspection alone and 53 fewer than would be missed by visual inspection plus dermoscopy), and OCT would lead to 93 false-positive results for BCC (a reduction in unnecessary excisions of 159 compared to using visual inspection alone and of 87 compared to visual inspection plus dermoscopy). Insufficient data are available on the use of OCT for the detection of melanoma or cSCC. Initial data suggest conventional OCT may have a role for the diagnosis of BCC in clinically challenging lesions, with our meta-analysis showing a higher sensitivity and higher specificity when compared to visual inspection plus dermoscopy. However, the small number of studies and varying methodological quality means implications to guide practice cannot currently be drawn.Appropriately designed prospective comparative studies are required, given the paucity of data comparing OCT with dermoscopy and other similar diagnostic aids such as reflectance confocal microscopy.

Improving results in patients with foramen magnum meningiomas by translating surgical experience into a classification system and complexity score.

Foramen magnum meningiomas (FMMs) are challenging lesions and controversy still exists regarding their optimal management. In the present paper, we propose some principles of surgical treatment of FMMs. We analyzed our series of 39 patients: the average maximum diameter was 31.1mm (sd, 10.7). In two cases, there was extradural extension. We operated all anterior lesions through dorsolateral approach to craniovertebral junction and all posterior lesions through midline suboccipital approach and C1 laminectomy, following the prevalence of side of the tumor. There were no complications except for one case of post-operative hypoglossus paresis. We translated our experience with surgery of foramen magnum meningiomas into a classification system and a complexity score, in order to assign a score to each individual case and plan the surgical strategy. When the complexity score is 5 or more, we propose subtotal removal, in consideration of the benign nature.

Zilver PTX Post-market Surveillance Study of Paclitaxel-Eluting Stents for Treating Femoropopliteal Artery Disease in Japan: 2-Year Results

PurposeA prospective, multicenter post-market surveillance study in Japan evaluated the 2-year safety and effectiveness of the DES in real-world patients with complex femoropopliteal artery lesions.MethodsThere were no exclusion criteria, and consecutive symptomatic patients with femoropopliteal lesions treated with the DES were enrolled in the study. Clinically driven target lesion revascularization (TLR) was defined as reintervention performed for > 50% diameter stenosis after recurrent clinical symptoms of peripheral arterial disease. Clinical benefit was defined as freedom from persistent or deteriorating ischemic symptoms. Patency was evaluated by duplex ultrasound where physicians considered this standard of care.ResultsIn this study, 905 patients were enrolled at 95 institutions in Japan. There were numerous comorbidities including a high incidence of diabetes (58.8%) and chronic kidney disease (43.6%). Additionally, 21.4% of patients were classified with critical limb ischemia. Lesions were complex, with an average length of 14.6 ± 9.6 cm (range 0.5–40 cm), 41.5% total occlusions, and 18.7% in-stent restenosis. In total, 1861 DES were placed in 1080 lesions. Two-year follow-up was obtained for > 90% of eligible patients. Freedom from TLR was 83.7%, and clinical benefit was 80.0% through 2 years. The 2-year primary patency rate was 70.3%. Rutherford classification significantly improved (p < 0.01), with approximately 80% of patients classified as Rutherford class 0 or 1 at 2 years.ConclusionDespite more challenging lesion characteristics, 2-year results from the current study are similar to outcomes from the previous Zilver PTX studies, confirming the efficacy of the Zilver PTX DES in a complicated femoropopliteal lesion (Zilver PTX Post-Market Study in Japan; NCT02254837).Level of EvidencePost-market surveillance study, Level III.

Occipital Artery to Posterior Cerebral Artery Bypass Using Descending Branch of the Lateral Circumflex Femoral Artery Graft for Treatment of Fusiform, Unruptured Posterior Cerebral Artery Aneurysm: 3-Dimensional Operative Video.

Posterior cerebral artery (PCA) aneurysms can be technically challenging lesions due to the intricacy of perforating branches and the relationship to cranial nerves and the brainstem. Fusiform aneurysms of the perimesencephalic segment of the PCA are a rare finding which does not favor direct clip occlusion or reconstruction. In such cases, proximal parent vessel occlusion is an option for aneurysm treatment. Extracranial-intracranial (EC-IC) bypass can be used to revascularize beyond the lesion when considering proximal occlusion. Based on previous literature for occipital artery (OA) bypass and the time-consuming dissection required for OA harvest, an interposition graft was chosen. The descending branch of the lateral circumflex femoral artery (DLCFA) is a good alternative interposition graft with a diameter that is favorable for revascularizing smaller, more distal vessels.This 3-dimensional video presents the case of a 26-year-old female with severe headaches who was found to have unruptured, fusiform aneurysmal dilatations of the PCA. Given the patient's youth and the morphology of the aneurysms, an EC-IC bypass with proximal occlusion was recommended. The DLCFA was used as an interposition graft. The left OA was found to be a suitable donor. A subtemporal approach was used to access the PCA for proximal occlusion. An occipital interhemispheric approach was performed to isolate a suitable recipient segment of the ipsilateral PCA branch for microvascular end-to-side anastomosis. Postoperative catheter angiography showed significant thrombosis of the fusiform aneurysms and a patent EC-IC bypass. Postoperative magnetic resonance imaging showed no infarcts and the patient was discharged neurologically intact.The patient was consented for inclusion in a prospective institutional review board (IRB) approved database from which this IRB approved retrospective report was performed. The consent for intraoperative video and picture use was also obtained.Images in the video between 0:49 and 1:11, © University of Southern California Neurorestoration Center. Used with permission, all rights reserved.

Isolated “Nutcracker” Fracture of the Anterior Calcaneal Process: do we need a more Comprehensive Classification for this Inury Spectrum? A Case Report

Fractures of the anterior calcaneal process are relatively rare accounting for 3-15% of all calcaneal fractures and can occur due to high or low energy trauma. Avulsion fractures are generally due to forced inversion and plantar flexion of the foot and are associated with ligament tears. More are impaction fractures, i.e. nutcracker fractures, are commonly described as due to a forced eversion and abduction of the foot with compression forcing the anterior process of the calcaneus against the cuboid. Clinical features are subtle and X-ray examination for the diagnosis of anterior calcaneal process fracture is challenging. A CT examination can reveal the fracture and should be performed whenever a doubt exists for correct diagnosis. Here we present the unique clinical case of a 44ys old female patient who suffered an isolated compression fracture of the anterior calcaneal process due to a fall from a stair with forced foot eversion and low energy trauma mechanism. The patient healed uneventfully with a conservative treatment. A more comprehensive classification of this spectrum injury is sought as many different fracture or combined bone-ligamentous lesions exist requiring different surgical or non surgical management. Actually, no clear guidelines exist in literature assisting the treating physician in the management of such challenging lesions.

Efficacy and safety of an internal magnet traction device for endoscopic submucosal dissection: ex vivo study in a porcine model (with video).

Appropriate traction allows for safer and easier endoscopic submucosal dissection (ESD). The aim of this study was to evaluate the efficacy and safety of an internal magnet traction device (MTD) for ESD in an ex vivo porcine model. The MTD consisted of a small neodymium magnet and a suture attached to a through-the-scope clip. A circumferential mucosal incision was completed around a 30-mm diameter template that served as the target lesion. The first MTD was deployed at the proximal edge of the lesion. A second MTD was deployed on the wall opposite the lesion. With both magnets connected, this created traction or lifting of the target lesion towards the opposing wall during submucosal dissection. Primary endpoint was comparison of submucosal dissection times between conventional ESD (C-ESD) and MTD-assisted ESD (MTD-ESD). Twenty lesions along the anterior wall, posterior wall and greater curvature were resected using either C-ESD or MTD-ESD. The submucosal dissection time in MTD-ESD was significantly shorter than C-ESD (median: 6.4 [interquartile range {IQR} 4.6-8.7] min vs. 14.4min [IQR 11.8-18.0], p < 0.05). There was a significant difference between MTD-ESD and C-ESD in total procedure times for lesions on the posterior gastric wall and greater curvature (median: 23.0min [IQR 21.1-24.5] vs. 29.2min [IQR 24.8-33.2], p < 0.05) with no difference for lesions on the anterior gastric wall (median: 18.8min [IQR 15.5-20.5] vs. 17.1min [IQR 13.1-20.0], p = 0.5). The number of muscularis propria injuries per lesion was significantly lower in MTD-ESD than C-ESD (median: 0 [IQR 0-0] vs. 1 [IQR 0-2], p < 0.05). MTD for ESD is effective and safe when compared to C-ESD. This approach significantly reduced submucosal dissection times with less injury to the muscularis propria. Furthermore, MTD-ESD was particularly beneficial for more challenging gastric lesions located on the posterior wall and greater curvature.

Adjunctive Thermoprotection During Percutaneous Thermal Ablation Procedures: Review of Current Techniques.

Although rare, unintended thermal injury to organs surrounding the ablation zone can lead to severe complications. Over the past 15years, different protective methods have been developed to limit risk of complications, and expand indications to include more challenging lesions in various locations including liver, kidney, lung and bone. The most frequently used techniques include hydrodissection, carbodissection, balloon interposition and probe torqueing. In most cases, tumours can be physically separated from sensitive structures, reducing risk of thermal injury. Endoluminal cooling/warming is an alternative option for complex ablations close to the ureter or major bile ducts. Different techniques may be combined to achieve successful protection in locations with complex anatomy. The purpose of this review is to provide an overview of available protective measures and discuss respective advantages/drawbacks.

Breast Tumours Resembling the Tall Cell Variant of Thyroid Papillary Carcinoma: Are They Part of the Papillary Carcinoma Spectrum or a Distinct Entity?

Background: Papillary tumours of the breast are diagnostically challenging lesions and represent a wide spectrum of diseases from papilloma to invasive papillary carcinoma. A rare subtype of breast papillary tumour resembling the tall cell variant of thyroid papillary carcinoma (BTRTPC) has been described. The nomenclature of this entity, its relationship to other papillary tumours, and its nature, whether in situ or invasive, remain unclear. Methods: Seventy-five papillary carcinomas (PCs) of the breast previously diagnosed in routine practice were reviewed and the presence of features (n = 10) characteristic of BTRTPC were assessed to determine whether BTRTPC comprises a distinct entity or is part of the spectrum of the previously defined PC variants. Results: Nuclear overlapping and eosinophilic granular cytoplasm were seen in 81 and 75% of the cases, whereas nuclear grooves, nuclear clearing, and tall cells were noticed in 51, 42, and 38% of the cases, respectively; 27% of the cases showed macro- and micro-follicular architecture filled with colloid-like material. Five cases (7%) lacked oestrogen receptor (ER) expression. Co-existing invasive carcinoma was seen in 25 cases (33%). Two cases displayed several features characteristic of BTRTPC, and both were ER-negative. Conclusion: Features characteristic of BTRTPC overlap with other PCs of the breast. Molecular and immunohistochemical biomarkers are needed to provide objective diagnostic criteria for the characterisation of such lesions in routine practice.

Proceedings of the 2018 National Toxicology Program Satellite Symposium

The 2018 annual National Toxicology Program Satellite Symposium, entitled "Pathology Potpourri," was held in Indianapolis, Indiana, at the Society of Toxicologic Pathology's 37th annual meeting. The goal of this symposium was to present and discuss challenging diagnostic pathology and/or nomenclature issues. This article presents summaries of the speakers' talks along with select images that were used by the audience for voting and discussion. Various lesions and other topics covered during the symposium included seminiferous tubule dysgenesis in rats, ameloblast and odontoblast degeneration/necrosis in a Sprague Dawley rat, intestinal leiomyositis in a beagle dog, gallbladder mucinous hyperplasia, focus of hepatocellular alteration and bile duct alteration in otters, renal tubule cytoplasmic vacuolation with basophilic granules in mice treated swith antisense oligonucleotide therapy, a uterine choriocarcinoma in a rhesus macaque, and rete ovarii proliferative ovarian lesions in various aged rat strains. One particularly provocative lesion was a malignant neoplastic proliferation in the renal pelvic region of a cynomolgus macaque from a 21-day study. Additional challenging lesions included thyroid proliferative lesions in zebra fish and gross findings in fish larvae during routine chemical screening. The Rabbit and Minipig International Harmonization of Nomenclature and Diagnostic Criteria Organ Working Groups also presented a series of challenging lesions.

GW29-e1527 "Balloon-stent kissing" technique avoid side-branch compromise for simple true bifurcation lesions

Coronary bifurcation remains one of the most challenging lesion subsets in interventinal cardiology. Moreover, different treatment techniques of bifurcation may also cause different dynamic changes in the anatomy (plaque or carina shift and dissection). Provisional stenting is the dominate technique

Radiological and biomechanical assessment of displaced greater tuberosity fractures

PurposeGreater tuberosity fractures are challenging lesions concerning decision-making. In order to improve our treatment algorithm, we developed a new method, which allows predicting a possible subacromial conflict on standard anteroposterior radiographs, considering not only the displacement of the fragment but also the width of the subacromial space.MethodsThe measurement technique consisted of drawing three concentric circles on true anteroposterior radiographs. The inner circle (radius Rh) perfectly matched the humeral head surface. The medial circle (radius Rt) was tangent to the greater tuberosity, and the outer circle (radius Ra) touched the undersurface of the acromion. The ratio Rt/Rh, which describes how much the greater tuberosity projects above the articular surface, and the relationship (Rt-Rh)/(Ra-Rh), which quantifies the space occupied by the greater tuberosity under the acromion, were calculated and called Greater Tuberosity Index and Impingement Index, respectively. Five dry humeri were used to assess the influence of rotation and abduction on the Greater Tuberosity Index. The radiographs of 80 shoulders without any osseous pathology were analyzed to obtain reference values for both indices. Finally, greater tuberosity fractures with different displacements were created in five cadaver specimens, and subacromial impingement was correlated with these parameters.ResultsOn anteroposterior radiographs, the greater tuberosity was most prominent in neutral rotation, regardless of abduction. In shoulders without osseous pathology, the Greater Tuberosity Index and the Impingement Index averaged 1.15 (range 1.06–1.28) and 0.46 (range 0.21–0.67). In the biomechanical experiments, the Impingement Index was a better discriminator for subacromial impingement than the Greater Tuberosity Index. A fracture with a displacement corresponding to an Impingement Index of 0.71 or greater was associated with subacromial impingement.ConclusionsReduction of a displaced greater tuberosity fragment should be considered if the Impingement Index is 0.7 or greater. The measurement method is simple and reliable and has the potential to be used for the assessment of subacromial impingement in other conditions.

Gross Total Resection of Large Cerebellopontine Angle Meningioma with a Supratentorial Extension via Retrosigmoid Approach with Suprameatal Drilling and Tentorial Sectioning.

Meningiomas are the second most common neoplasm in the cerebellopontine angle (CPA), and are challenging lesions to treat surgically. With significant refinements in surgical techniques, operative morbidity, and mortality have been substantially reduced. Total or near-total surgical resection can be accomplished in the majority of cases via appropriately selected approaches, and with acceptable morbidity. In this video, we present a 51-year-old woman, who had a 2-year history of vertigo with symptoms that progressed over time. She presented with blurry vision, sensorineural hearing loss, tinnitus, left-sided facial numbness, and double vision. Magnetic resonance imaging (MRI) showed a left-sided homogeneously enhancing mass at CPA with a supratentorial extension. MRI appearance was consistent with a CPA meningioma with supratentorial extension. The patient underwent surgical resection via a retrosigmoid approach. Suprameatal drilling and tentorial sectioning were necessary to achieve gross total resection. The surgery and postoperative course were uneventful. The histopathology was a WHO (world health organization) grade I meningioma. MRI showed gross total resection of the tumor. After a 1.5-year follow-up, the patient is continuing to do well with no residual or recurrent disease. In this video, microsurgical techniques and important steps for the resection of this challenging meningioma of the cerebellopontine angle are demonstrated. The link to the video can be found at: https://youtu.be/CDto52GxrG4 .