Classic Dissection Research Articles

К вопросу о селективных шейных лимфодиссекциях в терапии рака слизистой оболочки полости рта

Background. Incidence of oral cancer in Russia is 4.52 and mortality - 2.44. Head and neck cancer is characterized by the high risk of development of metastases in regional lymph nodes (LN). LN status exerts influence on the treatment plan and appears to be the major predictive factor. Regional metastases result into two-fold decrease of five-year survival. Treatment of metastatic LN is of prime importance.Objective. The aim of this manuscript was to illustrate and summarize publications devoted to selective neck dissections in patients with squamous cell carcinoma of the oral cavity (OC).Results. Classic radical neck dissection is the gold standard of surgical treatment of OC cancer, characterized by regional metastases. However, metastases in neck LN of the IV- and V-th level are rarely present in patients with oral cancer. Therefore, efficiency of less extensive neck surgery is of great interest of up-to-date investigations. It was established, that selective neck dissection increases disease-free survival among patients with cT1-4N0M0 oral cancer in comparison with watchful waiting. Comparison of preventive selective neck dissections with preventive and curative modified neck dissections also indicates, that these methods of surgical treatment have equal efficacy.Conclusion. Selective neck dissection is feasible treatment method of сT1-4N0M0 oral cancer. Nevertheless, comparison studies of preventive selective and modified neck dissections, were characterized by disparate design and high probability of systematic errors. Moreover, another aspect, that must be solved, is the number of LN levels to be dissected during selective neck dissection. Thus, conception of selective neck dissection in patients with clinically negative LN is changing and requires further investigation.

Is it really useful the Harmonic scalpel in axillary dissection for locally advanced breast cancer? A case series.

The seroma is one of the most common complications in the axillary lymph nodal dissection (different surgical approaches have been tried to reduce the seroma incidence). In our study we evaluate the outcome of patients using or not the ultrasonic scalpel (Harmonic scalpel) according to a standardized surgical technique. From January 2011 to December 2015 120 patients underwent axillary dissection for breast cancer. Patients were divided in two groups: patients belonging to the first group underwent Harmonic scalpel dissection and patients belonging to the second group underwent classical dissection. Each group consisted of 60 patients. Quadrantectomy (QUAD) was performed in 54 patients, 66 women underwent mastectomy. In all patients axillary dissection included the I, II and III level. We compared two groups in terms of: time of surgery, hematoma, drainage volume, days of sealing drainage, seroma formation, number of post-seroma aspirations, upper limb lymphedema, wound infections, post-operative pain. Statistically significant results were obtained in terms of the total volume of the breast and axillary drainage in the two techniques. There were no significant differences in the two samples in terms of operative time incidence of seroma, post-operative hematoma, wound infection, and lymphedema of the upper limb. The small number of cases did not allow us to reach definitive conclusions. The use of Harmonic scalpel seems to show smaller incidence of seroma and reduction of the amount of both breast and axillary drainages. Further studies are needed to define the real advantage in terms of cost benefit of using these devices in the axillary surgery.

Adapting anatomy teaching to surgical trends: a combination of classical dissection, medical imaging, and 3D-printing technologies.

Many regions worldwide report difficulties in recruiting applicants to surgery. One strategy proposed to reverse this trend consists of early exposure of medical students to the field. Against this backdrop, the present study presents an innovative approach for anatomy teaching, integrating a surgically relevant trend: 3D printing. Whole-body computed tomography (CT) was made of two cadavers. Twelve students performed measurements and 3D reconstructions of selected anatomical structures (Osirix, Mimics). 3D printed (3DP) models were obtained (ZPrinter 310 Plus), and the students completed the analogous measurements on these replicas. Finally, classical anatomical dissection was performed and the same parameters were measured. The differences between the values obtained by the three modalities were submitted to standard statistical analysis (Wilcoxon two-tail paired test). Qualitative comparison of the digital 3D reconstructions based on the students' manual CT segmentation and the anatomical reality showed excellent correlation. Quantitatively, the values measured on the CT images and the physical models created by 3D printing differed from those measured on the cadavers by less than 2mm. Students were highly appreciative of the approach (CT, 3DP, cadaver). Their average satisfaction score was 5.8 on a 1-6 scale. This study shows that the approach proposed can be achieved. The results obtained also show that CT-based 3D printed models are close to the authentic anatomic reality. The program allows early and interactive exposure of medical students to a surgically relevant trend-in this case 3D printing.

Endovascular Treatment of Two Penetrating Ascending Aortic Ulcers: A Case Report

Endovascular Treatment of Two Penetrating Ascending Aortic Ulcers: A Case Report

Branching patterns of the foetal popliteal artery.

The objective of the study is to evaluate the popliteal artery topography and the origin variability of its branches in human foetuses at the gestational age of from 4 to 9 months. The basis for the analysis are direct observations of classic anatomic dissections of the popliteal fossa. Possible dimorphic and bilateral differen- ces, as well as the gestational age variability at the foetal period, were considered. A typology of popliteal artery branches will be made on the basis of the studies. The research material of this study comprises 231 foetuses (including 116 males and 115 females). The foetuses were divided into five 28-day age classes. The vessels of the lower extremity were injected with LBSK 5545 latex through the femoral artery. The bilateral dissection of the po- pliteal artery along with its branches was performed. No visible malformations were found in the research material, and the foetuses came from spontaneous abortions and premature births. Ten per cent of the cases featured the variations of popliteal artery terminal branches. Three most commonly seen variations are the trifurcation, anterior tibial-peroneal trunk, and high terminal division of the po- pliteal artery. The most common course of the superior muscular branches is that there are two large branches which are distributed from the popliteal artery at the height of the knee joint cavity and they do not distribute cutaneous branches. Sural branches are also present as two large vessels without cutaneous branches. The genicular anastomosis branches that run on their own are a typical topographic system of these branches.

Actualización sobre las características pronósticas y el manejo terapéutico de la úlcera aórtica penetrante

Penetrating aortic ulcer is a rare and underdiagnosed condition, with its own characteristics regarding classical dissection. An updated review is presented, focusing on its prognosis and therapeutic management.

Intra-articular accessory cartilage fragments in fossa olecrani

Elbow injuries are common, diverse and very painful. They can affect the muscles and the neurovascular bundle, as well as, the elbow joint itself (articulatio cubiti). ObjectiveTo present a case of the anatomical variation cartilago supratrochlearis dorsalis. Materials and methodsThe classical layered dissection method was used during the education of students at the Medical University of Plovdiv, Department of Anatomy, Histology and Embryology. ResultsA deformed circumferentia articularis radii with a 9mm in diameter erosion in fovea capitis radii. Fossa olecrani has a preserved form and size and contains three accessorious, flat, well confined, hard formations – rhombus-shaped (5/4mm), elliptical-shaped (4/2mm), bisegmented with an irregular shape (6/4mm). No pathologies of the olecranon were identified.Besides the typical chondrocytes, no inflammatory cells were found – plasma cells, histiocytes and foreign-body cells. The connective tissue matrix is not homogeneous. No signs of ossification are found.

A New Twist on PBL: A Pilot Study of a Problem‐based Dissection Exercise

According to the Liaison Committee on Medical Education, active learning has been defined in part as “the process by which a medical student, independently, or collaboratively with his/her peers, identifies his/her learning objectives and seeks the information necessary to meet the objectives.” Engaged learning practices have been incorporated into our gross anatomy course (e.g. flipped classroom, cooperative learning), however these do not satisfy the standard mentioned above. This year a problem‐based dissection (PBD) exercise was piloted in the gross anatomy course for year 1 medical students. For one laboratory, students were given a clinical case in lieu of classic dissection instructions. Each anatomy group was asked to prepare learning objectives to research in order to solve the case. Additionally, each group formulated a dissection plan, completed the dissection, and presented their results to a faculty member in the anatomy laboratory. Preliminary assessments indicate that students felt more prepared and knowledgeable about the dissection for the PBD exercise compared to traditional laboratories. However, results also show that students felt less confident and less enthusiastic about completing the PBD exercise compared to dissections where instructions were provided. The effect on group dynamics, teamwork and communication skills is currently being assessed and will be reported.

Thoracoscopic tunnel technique for anatomical lung resections: a 'fissure first, hilum last' approach with staplers in the fissureless patient.

To minimize air leak after anatomical lung resections, many video-assisted thoracic surgery (VATS) surgeons use a 'fissureless' technique, using staplers to divide the hilar bronchovascular structures first and the main part of the fissure last. We describe a cohort of 198 consecutive patients operated with an alternative fissureless technique, opening the fissure completely with staplers at an early stage of the VATS anatomical lung resection. To open the incomplete fissure first and with staplers, a tunnel dissection is started anterior between the triangle of pulmonary veins and the parenchyma. After identification of the pulmonary artery, the anvil of a first stapler is placed on top of the artery and the anterior part of the fissure is divided. Dissection between artery and parenchyma is continued until the fissure is completely stapled. From a prospectively managed single institution database, we retrieved 405 patients scheduled for VATS anatomical resection between October 2009 and December 2014. The patients were categorized in four consecutive periods: a learning curve with the first 50 cases of VATS lobectomy technique (LC), a period of consecutive 'hilum first, fissure last' (HF), a transition group (TG) during which both techniques were used and a period of consecutive 'fissure first, hilum last' (FF). No significant differences in operating time, frequency of prolonged air leak or hospital stay were observed between HF (n = 45) and FF (n = 198). Chest tubes were removed earlier in the FF period (6.9 vs 5.2 days, P = 0.025). Excluding the learning curve, we found 2 patients (2.8%) operated 'hilum first' with an intraoperative complication that potentially could have been avoided by a 'fissure first' technique. By making a tunnel between the bronchovascular structures and parenchyma from anteriorly to posteriorly, one can open the fissure completely with staplers at an early stage of an anatomical lung resection. This combines the advantages of both the 'fissureless' hilum first technique and classic (open) fissure first dissection, i.e. minimal air leak and optimal anatomical overview before bronchovascular structures are divided, potentially avoiding inadvertent transections. A cohort of 198 consecutive patients operated with this alternative fissureless technique demonstrates the feasibility and non-inferiority regarding hospital stay, chest tube duration, operation time and complications in comparison with the hilum first technique.

SmartClamp circumcision versus conventional dissection technique in terms of parental anxiety and outcomes: A prospective clinical study.

We prospectively analyzed parental anxiety and outcomes of the SmartClamp circumcision and the classic surgical dissection technique. A total of 250 boys underwent circumcision between 2009 and 2012 at Kars State Hospital and Kafkas University Faculty of Medicine in Turkey. The initial 125 children were circumcised by conventional dissection method and the remaining children were operated on with a SmartClamp device. Children in both groups were compared in terms of bleeding, infection, penile edema, operative time, cosmetic result, length of the inner mucosal layer, and parental anxiety. We used a State-Trait Anxiety Inventory (STAI) form to gauge how the circumcision affected parental anxiety. This form was completed by parents on postoperative day 2. There were no statistically significant differences among the 2 groups in terms of age, bleeding, infection, and cosmetic displeasure (p > 0.05). The STAI scores of the parents from the SmartClamp group were statistically higher than that of the other group (p < 0.001). Penile edema was more common in the SmartClamp group (p = 0.039). However, the mean operative time was statistically shorter (p < 0.001) and the inner mucosal length was significantly longer in the SmartClamp group (p < 0.001). Circumcision with the SmartClamp device was faster. Cosmetic results and complication rates were similar. Unfortunately, this technique seemed to entail the disadvantages of longer mucosal length, penile edema, and higher parental anxiety. Urologists should keep these points in mind when choosing a technique.

Fatal Type A Aortic Dissection in Young Giving Appearance of Double Aortic Valve with Worms in the Aorta

Aortic dissection is a devastating complication which can lead to a fatal outcome. We are here presenting a 25 year old male gentleman presented with history of sudden onset of chest pain and breathlessness of 2 hour duration. Emergency transthoracic echocardiography (TTE) showed dilated aortic root with acute aortic regurgitation and dissection flaps giving the impression of an double aortic valve and worms moving in aorta (Images and Videos 1-3).The cause of the dissection in this patient was previously unrecognised bicuspid aortic valve (Image and Video 4) with aortic root dilatation. The early mortality rate in patients with acute aortic dissection is very high, with up to a 1% per hour death rate reported in the first several hours before surgery for type A dissection. TTE has a sensitivity of 77% to 80% and a specificity of 93% to 96% for the identification of proximal aortic dissection, but it is much less sensitive (31% to 55%) than other modalities for the diagnosis of distal aortic dissection.TEE or CT are imaging modalities of choice. In our patient the entire dissection could be delineated with TTE with classical dissecting flaps seen as worms in aorta.

Invited Commentary

Since the seminal article published by Hirst and colleagues in 1958 [1Hirst Jr., A.E. Johns Jr., V.J. Kime Jr., S.W. Dissecting aneurysm of the aorta: a review of 505 cases.Medicine (Baltimore). 1958; 37: 217-279Crossref PubMed Scopus (1127) Google Scholar], the mortality associated with acute type A aortic dissection has remained astoundingly high: 75% of patients expire within 2 weeks without undergoing an operation. However, information on the fortunate few who survive the initial event is very limited. The data presented in this article are quite valuable because they outline a spectrum of presentation, predisposing conditions, surgical outcomes, and long-term survival for patients with a chronic type A dissection [2Rylski B. Milewski R.K. Bavaria J.E. Branchetti E. Vallabhajosyula P. Szeto W.Y. Desai N.D. Outcomes of surgery for chronic type A aortic dissection.Ann Thorac Surg. 2015; 99: 88-94Google Scholar]. Amazingly, but consistent with what most of us have witnessed, a majority of patients were found to have a chronic dissection by serendipity. Few had symptoms related to the dissection, and a majority could not recall an event that one might ascribe to a dissecting aorta. Although the aortas in the cohort with chronic dissections were generally larger, with more severe aortic valve insufficiency and with worse left ventricular function than their counterparts with acute dissections, it was quite rare for a patient to present with either rupture or malperfusion and in need of an emergent operation. This more elective presentation, and the time it allowed for more thorough preoperative evaluation and normalization of end organ function, was a major contributor to the three-fold reduction in perioperative mortality seen when operations were performed beyond the acute phase. These patients were also fortunate in that the dissection extended beyond the arch less than one-third of the time. This not only made the surgical procedure less complicated but also improved long-term survival by eliminating the need for a high-risk downstream operation on the dissected thoracoabdominal aorta. Two additional pieces of information extracted from these data are worthy of further discussion. First, acute type A intramural hematoma does not appear to be a benign disease. Six patients with an intramural hematoma were followed up after the acute event. Although none experienced a rupture or an adverse event during a period of observation, all went on to need operations for aortic expansion, conversion to classic dissection, or experience ongoing symptoms. It may be more logical to proceed with surgery at the time of presentation and eliminate the potential risk one might incur by waiting for the inevitable need for an operation. The second issue surrounds the indications for an operation. The authors suggest a diameter of 5.5 cm or more as an indication to proceed with repair. Although this may be reasonable in patients with advanced comorbidities or mediastinal scarring after previous heart operations, it seems counterintuitive that any chronic type A dissection should be followed irrespective of diameter. Perhaps data will surface describing a similar cohort of patients with small aortic diameters who were safely followed with serial imaging. However, given the relatively low perioperative risk and excellent long-term survival experienced by these patients, it seems more reasonable to support a more aggressive surgical approach in any patient found to have a chronic type A dissection. Outcomes of Surgery for Chronic Type A Aortic DissectionThe Annals of Thoracic SurgeryVol. 99Issue 1PreviewData on outcomes of surgery for chronic Stanford type A aortic dissection are limited. We investigated the primary surgery and long-term results in patients with chronic dissection of the native ascending aorta. Full-Text PDF

Abstract 19354: Management and Outcomes of Acute Type B Dissection in IRAD Treated with Open Surgery, Endovascular Flap Fenestration or TEVAR

Background: The debate for the optimal treatment of complicated Type B Acute Aortic Dissection (TBAAD) is primarily focused upon open surgical intervention versus thoracic endovascular aortic repair (TEVAR). The technique of fenestration with stenting has been proposed to resolve malperfusion. This study evaluated post-procedural outcomes of all three approaches for TBAAD. Methods: TBAAD patients enrolled in the International Registry of Acute Aortic Dissection were stratified by management type: TEVAR, fenestration and stenting, and surgery. Results: Of the 552 patients with TBAAD, 231 (41.8%) underwent TEVAR, 214 (38.8%) standard open surgery, and 107 (19.4%) fenestration and stenting. TEVAR or fenestration and stenting were more likely to be performed in classic double barrel aortic dissection when compared to open surgery (73.2%, 76.6%, 52.8% respectively; p&lt;0.001). Patients treated with open repair were less likely to have distal extension into the abdominal aorta than those with TEVAR or fenestration and stenting (47.7%, 62.7%, 86.4%, respectively; p&lt;0.001). In-hospital mortality was similar between groups (11.7% TEVAR, 14.0% fenestration and stenting, 15.9% surgery). At five years, Kaplan-Meier post-discharge all-cause survival estimates were highest for TEVAR, followed by endovascular fenestration and finally open surgical intervention (85.2%, 78.3%, 67.2%, respectively; p=0.039). Conclusion: Patients treated by endovascular approaches, whether with flap fenestration or thoracic endovascular aortic repair, had lower five year mortality when compared to patients who required open repair in the setting of TBAAD. Either endovascular approach may be helpful in the treatment of TBAAD. Further research is needed to determine how much of the observed difference represents patient selection versus differential effects of treatment.

The Sihler staining study of the infraorbital nerve and its clinical complication.

The infraorbital nerve (ION) is a cardinal cutaneous nerve that provides general sensation to the mid face. Its twigs are vulnerable to iatrogenic damage during medical and dental manipulations. The aims of this study were to elucidate the distribution pattern of the ION and thus help to prevent nerve damage during medical procedures and to enable accurate prognostic evaluation where complications do occur. This was achieved by treating 7 human hemifaces with the Sihler modified staining protocol, which enables clear visualization of the course and distribution of nerves without the accidental displacement of these structures that can occur during classic dissection. The twigs of the ION can be classified into the usual 5 groups: inferior palpebral, innervating the lower eyelid in a fan-shaped area; external and internal nasal, reaching the nosewing and philtrum including the septal area between the nostrils, respectively; as well as medial and lateral superior labial, supplying the superior labial area from the midline to the mouth corner. Of particular note, the superior labial twigs fully innervated the infraorbital triangle formed by the infraorbital foramen, the most lateral point of the nosewing, and the mouth corner. In the superior 3-quarter area, the ION twigs made anastomoses with the buccal branches of the facial nerve, forming an infraorbital nervous plexus. The infraorbital triangle may be considered a dangerous zone with respect to the risk for iatrogenic complications associated with the various medical interventions such as implant placement.

Diagnosis and management of acute aortic syndromes: dissection, intramural hematoma, and penetrating aortic ulcer.

Acute aortic syndromes constitute a spectrum of conditions characterized by disruptions in the integrity of the aortic wall that may lead to potentially catastrophic outcomes. They include classic aortic dissection, intramural hematoma, and penetrating aortic ulcer. Although imaging studies are sensitive and specific, timely diagnosis can be delayed because of variability in presenting symptoms and the relatively low frequency with which acute aortic syndromes are seen in the emergency setting. Traditional classification systems, such as the Stanford system, facilitate early treatment decision-making through recognition of the high risk of death and major complications associated with involvement of the ascending aorta (type A). These patients are treated surgically unless intractable and severe co-morbidities are present. Outcomes with dissections that do not involve the ascending aorta (type B) depend on the presence of acute complications (e.g., malperfusion, early aneurysm formation, leakage), the patency and size of the false lumen, and patient co-morbidities. Patients with uncomplicated type B dissections are initially treated medically. Endovascular techniques have emerged as an alternative to surgery for the management of complicated type B dissections when intervention is necessary. Patients with acute aortic syndromes require aggressive medical care, risk stratification for additional complications and targeted genetic assessment as well as careful long-term monitoring to assess for evolving complications. The optimal care of patients with acute aortic syndrome requires the cooperation of members of an experienced multidisciplinary team both in the acute and chronic setting.

Treatment patterns and their outcomes of acute aortic intramural hematoma in real world: multicenter registry for aortic intramural hematoma.

BackgroundIntramural hematoma of the aorta (IMH), a variant of classic aortic dissection, shows very dynamic process in the early phase. The aim of this study is to evaluate clinical outcomes of patients with acute aortic IMH from real world registry data.MethodsWe analyzed 165 consecutive patients with acute IMH from five medical centers in Korea. All patients were divided into two groups; type A (n = 61, 37.0%) and type B (n = 104, 63.0%) according to the Stanford classification. Clinical outcomes and morphological evolution by CT were analyzed for 2 years.ResultsMost of the patients (77.0% of type A and 99.0% of type B, P < 0.001) were treated medically during their initial hospitalization. There were no significant differences in in-hospital mortality (4.9% vs. 2.9%, P = 0.671) and 2-year mortality (13.1% vs. 11.5%, P = 0.765) between two groups. During the 2-year follow up period, progression to aortic dissection (18.0% vs. 6.7%, P = 0.037) and surgical treatment (29.5% vs. 2.9%, P < 0.001) were higher in type A. For the type A patients, there were no significant difference in in-hospital mortality (7.1% of surgery vs. 4.3% of medical, P = 0.428) and 2-year mortality (7.1% of surgery vs. 14.9% of medical, P = 0.450) in terms of initial treatment strategy.ConclusionFor real world practice in Korea, most of IMH patients were treated medically at presentation and showed favorable outcomes. Thus, even in type A acute IMH, early medical treatment with alternative surgical conversion for selected, complicated cases would be a favorable treatment option.

Don't get in a flap!: A case report of progression through the spectrum of an acute aortic syndrome

To present a single case that clearly demonstrates the progression through the whole spectrum of an acute aortic syndrome, from a solitary penetrating aortic ulcer (PAU) through to multiple PAUs with intra-mural haematoma (IMH) progression. The index images show that despite the clinical presentation of an acute type B aortic dissection, a classical dissection flap is never demonstrated in this patient and thus highlights the need for early input from vascular surgery for all potential acute aortic syndromes. We present the case of a 71-year-old lady who attended the emergency department with hypertension and inter-scapular chest pain. Upon investigation with computed tomography aortography (CTA), she was found to have a solitary PAU only with minimal IMH. She did not demonstrate any classical radiological signs of acute type B aortic dissection. She was admitted under a medical team and her chest pain abated with no treatment. The treating medical team adjusted her anti-hypertensive medication and discharged her home with an urgent vascular surgical outpatient appointment for further follow-up and surveillance. We acknowledge that a preferred approach would have been, at least admission and close blood pressure monitoring, with a repeat CTA the next day. Two days later, she represented with further chest pain and on repeat CTA was found to have multiple PAUs and progression of the small IMH. She was then admitted under vascular surgery and subsequently transferred to the parent tertiary referral vascular surgical unit. Despite aggressive anti-hypertensive management, she had persistent intractable chest pain and was treated with a single thoracic stent graft. Completion angiography demonstrated total resolution of the PAUs. This case along with index images demonstrates the whole spectrum of the acute aortic syndrome from a solitary PAU to multiple PAUs with IMH extension. Despite an eventual clinical picture of an acute type B aortic dissection, there was a notable absence of a classical dissection flap on any imaging. We recommend that all aortic pathologies should be at least discussed with and preferably managed by vascular surgeons. The absence of a classical dissection flap on imaging is not a contra-indication to emergent treatment with thoracic stent grafting and in select patients is actually the only therapy that will treat this pathology.

Saphenous vein sparing superficial inguinal dissection in lower extremity melanoma.

Aim. The classic inguinal lymph node dissection is the main step for the regional control of the lower extremity melanoma, but this surgical procedure is associated with significant postoperative morbidity. The permanent lymphedema is the most devastating long-term complication leading to a significant decrease in the patient's quality of life. In this study we present our experience with modified, saphenous vein sparing, inguinal lymph node dissections for patients with melanoma of the lower extremity. Methods. Twenty one patients (10 women, 11 men) who underwent saphenous vein sparing superficial inguinal lymph node dissection for the melanoma of lower extremity were included in this study. The effects of saphenous vein sparing on postoperative complications were evaluated. Results. We have observed the decreased rate of long-term lymphedema in patients undergoing inguinal lymphadenectomy for the lower extremity melanoma. Conclusion. The inguinal lymphadenectomy with saphenous vein preservation in lower extremity melanoma patients seems to be an oncologically safe procedure and it may offer reduced long-term morbidity.

Anatomic Study of the Central Core of the Cerebrum Correlating 7-T Magnetic Resonance Imaging and Fiber Dissection With the Aid of a Neuronavigation System

Different strategies have been used to study the fiber tract anatomy of the human brain in vivo and ex vivo. Nevertheless, the ideal method to study white matter anatomy has yet to be determined because it should integrate information obtained from multiple sources. We developed an anatomic method in cadaveric specimens to study the central core of the cerebrum combining traditional white matter dissection with high-resolution 7-T magnetic resonance imaging (MRI) of the same specimen coregistered using a neuronavigation system. Ten cerebral hemispheres were prepared using the traditional Klingler technique. Before dissection, a structural ultrahigh magnetic field 7-T MRI study was performed on each hemisphere specifically prepared with surface fiducials for neuronavigation. The dissection was then performed from the medial hemispheric surface using the classic white fiber dissection technique. During each step of the dissection, the correlation between the anatomic findings and the 7-T MRI was evaluated with the neuronavigation system. The anatomic study was divided in 2 stages: diencephalic and limbic. The diencephalic stage included epithalamic, thalamic, hypothalamic, and subthalamic components. The limbic stage consisted of extending the dissection to complete the Papez circuit. The detailed information given by the combination of both methods allowed us to identify and validate the position of fibers that may be difficult to appreciate and dissect (ie, the medial forebrain bundle). The correlation of high-definition 7-T MRI and the white matter dissection technique with neuronavigation significantly improves the understanding of the structural connections in complex areas of the human cerebrum.

Physiological cross‐sectional area of the oblique head of the adductor pollicis is greater than its transverse counterpart: Implications for functional testing

Despite structural distinction between the transverse and oblique heads of the adductor pollicis, in vivo testing continues to consider the adductor pollicis as functionally simplistic. As a muscle's architecture is a strong indicator of function, in this study we aimed to determine whether the physiological cross-sectional areas (PCSAs) of both heads were uniform. Classical, microdissection, and chemical dissection procedures were conducted on 10 cadaveric left hands to determine structural origin and insertions. Architectural measures of muscle length (Lm ), muscle weight (Wm ), fascicle length (Lf ), sarcomere length (Ls ), and pennation angle (θ) were used to calculate PCSA and fascicle length:muscle length ratio (Lf :Lm ). The oblique head had greater variation in attachments, significantly greater PCSA (P = 0.008), and smaller Lf :Lm (P = 0.001) than its transverse counterpart. Muscle architecture suggests the oblique head has greater potential for force generation, and the transverse has greater potential for joint excursion.