Surgical Implications Research Articles

Surgery for pediatric drug resistant epilepsy: a narrative review of its history, surgical implications, and treatment strategies.

Drug-resistant epilepsy (DRE), also known as medically refractory epilepsy, is a disorder of high prevalence and negatively impacts a patients quality of life, neurodevelopment, and life expectancy. Pediatric epilepsy surgery has been conducted since the late 1800s, and randomized controlled trials have demonstrated the marked effectiveness of surgery on seizure reduction and the potential for cure. Despite the strong evidence for pediatric epilepsy surgery, there is also strong evidence describing its underutilization. The objective of this narrative review is to describe the history, strength, and limitations in the evidence of surgery for pediatric drug resistant epilepsy. This narrative review was conducted utilizing standard search engines to include the relevant articles on the topic of surgery for drug resistant epilepsy in children, with main keywords including surgery in pediatric epilepsy and drug-refractory epilepsy. The first components describe the historical perspective of pediatric epilepsy surgery and the evidence that highlight the strengths and limitations of epilepsy surgery. We then highlight the importance of presurgical referral and evaluation, followed by a section detailing the surgical options for children with DRE. Lastly, we provide a perspective on the future of pediatric epilepsy surgery. Evidence supports the role for surgery in pediatric medically refractory epilepsy in seizure frequency reduction, improved curative rates, and improvements in neurodevelopment and quality of life.

Morphometric Examination of the Sacroiliac Region and Variable Positions of the Sacral Auricular Surface: Anatomical Classification and Importance.

Anatomical variations of the sacrum involve alterations in the number of sacral segments, auricular surface area, and neural arch dimensions and are associated with biomechanical, surgical, and obstetric implications. Due to the complex functional structure of the sacroiliac (SI) joints, it was aimed to evaluate their morphometric structure, classify the sacrum, and group different locations of the auricular surface in the sacrums. Sex determination was made in 91 dry human sacra. Determination of the alpha angle on the sagittal axis of the auricular surface of the sacrum and classification of the auricular surface of the sacrum wasperformed.The sacra were studied to determine the position and extent of their auricular surfaces in relation to the sacral segments. Specimens were grouped as "normal," "high-up," and "low-down" auricular surface-bearing sacra. The sacral surface areas were measured, and SI joints were classified into three types morphologically (types I, II, and III). The depth and anterior-posterior length of the cranial, middle, and caudal impressions observed in the posterior sacrum and anterior-posterior lengths were measured. The measurements made for sex determination showed that 46 of the sacra were from females and 45 were from males.The alpha angle on the sagittal axis of the sacral auricular surface was found to be greatest at the level of the first posterior sacral foramina. While the most common sacrum type was Type III, the least common type was Type I. The surface area of facies auricularis was found to be larger in males than in females. With regard to facies auricularis in all sacrum groups, although it covered approximately 2.5 sacral vertebrae, there was a difference in the location of facies auricularis in the sacral vertebrae. A statistically significant difference was found between right and left in the depth values of the impressions in the dorsal surface of the sacrum (p <0.05). The position of the auricular surface in the sacrum differed among individuals. These differences are associated with variable load-bearing in the SI joints. The biomechanical classification of the sacrum and localization of the auricular surface can provide information about the anatomic source of low back pain or help predict the location of low back pain. Changes in the synovial surface morphology of the SI joints may elicit sacroiliac joint pain. This study was conducted because it is considered that the location of the auricular surface can significantly affect load-bearing patterns of the sacrum.

Uneventful Cochlear Implantation through Round Window Approach in a Child with Persistent Stapedial Artery: A Case Report

Persistent stapedial artery (PSA) is a rare congenital vascular anomaly, with both clinical and surgical implications. When encountered during middle ear surgery, it represents a challenge to the otologic surgeon, since damage to this artery could lead to massive intraoperative bleeding and poor surgical exposure. Here we report the case of a 3-year-old boy with prelingual and profound bilateral sensorineural hearing loss who was referred to our Otolaryngology-Head and Neck Surgery Department for cochlear implant evaluation. Pre-operative computed tomography (CT) examination of the temporal bone confirmed the diagnosis of PSA. Further evaluation showed no contraindication for surgery and the patient underwent cochlear implantation using the classic transmastoid, facial recess approach. During surgery the vessel was coursing far enough from the round window niche, making it possible to achieve safe and complete electrode insertion into the scala tympani of the cochlear basal turn. This case demonstrates that cochlear implantation is safe and feasible in patients with PSA. Thorough analysis of the preoperative temporal bone CT scan might help with surgical planning by identifying this anomaly prior to surgery.

The Middle Rectal Artery: Revisited Anatomy and Surgical Implications of a Neglected Blood Vessel.

Although the middle rectal artery is a relevant anatomical landmark for rectal resection and lateral lymph node dissection, descriptions of this entity are highly divergent. Dissection, visualization, morphometry, and 3-dimensional reconstruction of the middle rectal artery to facilitate its management in surgery. Macroscopic dissection, histologic study, morphometric measurements, and virtual modeling. University laboratory of applied surgical anatomy. This study includes formalin-fixed hemipelvis specimens (n=37) obtained from body donors (age, 67-97 y). The main outcome measures are photo documentation of origin, trajectory, diameter, and branching pattern; immunolabeling of lymphatics; and 3-dimensional reconstruction of the middle rectal artery. The middle rectal artery was present in 71.4% of body donors (21.4% bilateral, 50% unilateral), originated from the anterior division of the internal iliac artery, and branched either from the internal pudendal artery (45.5%), the inferior gluteal artery (22.7%), the gluteal-pudendal trunk (22.7%), or a trifurcation (9.1%). One to 3 branches of varying diameters (0.5-3.5 mm) entered the mesorectum from the ventrolateral (35.7%), lateral (42.9%), or dorsolateral (21.4%) aspect. The middle rectal artery was accompanied by podoplanin-immunoreactive lymphatic vessels and gave off additional branches (81.8%) to the urogenital pelvic organs. Three-dimensional reconstruction revealed the complex course of the middle rectal artery from the pelvic sidewall through the pelvic nerve plexus and parietal pelvic fascia into the mesorectum. Findings retrieved from body donors may be prone to age- and fixation-related processes. The investigation disclosed the rather high prevalence of the middle rectal artery, its 3-dimensional topographic anatomy, and its proximity to the autonomic pelvic nerves. These features play a role in the surgical management of this blood vessel. The data provide the anatomical rationale for the lateral lymphatic spread of rectal cancer and an anatomical basis for nerve-preserving lateral lymph node dissection.

Morphometric Study of Martin-Gruber Anastomosis and Its Surgical Implications: A Cross-sectional Cadaveric Study

Introduction: The Martin-Gruber anastomosis is a median- ulnar nerve communication in the upper part of the forearm. This anastomosis is classified into four types. Aim: To determine the incidence and morphometry of the Martin- Gruber anastomosis and recognise its surgical implications in the South Indian population. Materials and Methods: This cross-sectional study was conducted on 60 cadaveric upper limb specimens obtained from the Department of Anatomy, Rajarajeswari Medical College and Hospital, Bengaluru, Karnataka, India between November 2022 and March 2023. The median and ulnar nerves were traced, and the Martin-Gruber anastomosis was identified and documented. The classification devised by Nakashima T was used in present study. The distance from the medial epicondyle of the humerus to the point of anastomosis on the ulnar nerve was measured using Vernier calipers. The data were analysed using the statistical software Stastistical Packages for the Social Sciences (SPSS) version 23.0. Categorical variables were expressed as frequency and percentage, while continuous data were expressed as mean and standard deviation. Results: The Martin-Gruber anastomosis was observed in 11 out of 60 upper limb specimens (18.33%). Type I anastomosis was observed in 3 specimens (27.27%), Type II in 2 specimens (18.18%), and Type III in 6 specimens (54.4%). Type IV was not documented in present study. The distance from the location of the anastomosis on the ulnar nerve to the medial epicondyle of the humerus ranged from 2.2 cm to 13.2 cm, with an average of 3.5 cm. Conclusion: The findings of present study might be useful for neurosurgeons during nerve transfer techniques for chronic ulnar neuropathy, which is seen in the general population as well as athletes.

Petroclival Clinoidal Folds and Relationships with Arachnoidal Membranes of Medial Incisural Space: Old Neuroanatomical Terms for a New Neurosurgical Speech in Cadaver Labs with Limited Resources Era. Part III: Arachnoid Membranes, Cranial Nerves, and Surgical Implications.

BACKGROUND Anatomical dissections play an irreplaceable role in the training of new generations of effective neurosurgeons, especially when addressing skull base lesions is required.The Authors describe an inter-laboratory dissection study aimed at improving the knowledge of a complex region of the skull base. The anterior and middle incisural spaces are of remarkable anatomical and surgical interest due to complex relationships between bony, dural, arachnoidal, and neurovascular structures. The primary purposes of this study are to describe the anatomy of this region with particular emphasis on the relationships between the anterior margin of the free edge of the tentorium and the sphenoid and petrous bone; to identify surgical implications in many different types of neurosurgical procedures dealing with this challenging complex anatomic area.METHODS Thirteen anatomical specimens, including five injected specimens, were dissected in this study. In the formalin-fixed specimens, vessels were injected with colored silicone.RESULTS The anatomical study focused on the description of the relationships between bony dural, arachnoid, and neurovascular structures. Surgical implications are described accordingly.CONCLUSIONS Detailed anatomical knowledge of this region finds concrete applications in neurosurgical practice since the anterior and middle incisural spaces are often surgically exposed in neoplastic and vascular diseases. The high-definition pictures reported in this study could represent useful support to understand the anatomy of this complex region.Finally, our study could provide guidance to neurosurgical centers in which resources are limited that are either planning to establish their own cadaver dissection laboratory or failed to do so because of the supposed high-costs.

Petroclival Clinoidal Folds and Relationships with Arachnoidal Membranes and Neural Structures of Anterior and Middle Incisural Spaces: Old Neuroanatomical Terms for a New Neurosurgical Speech in Cadaver Labs with Limited Resources Era. Part I: Osteology and Structural Anatomy of Dura Mater.

Purpose The role of cadaver labs in preparing new generations of effective neurosurgeons is of paramount importance. The Authors describe a personal cadaver lab experience aimed at improving the knowledge of a difficult region of the central skull base. The anterior and middle incisural spaces are regions of remarkable anatomical, and surgical interest due to complex relationships between bony, dural, arachnoidal, and neurovascular structures. The primary purpose of this study is (1) to describe the anatomy of this region with particular emphasis on the relationships between the anterior margin of the free edge of the tentorium and the sphenoid and petrous bone; (2) to identify surgical implications in many different types of neurosurgical procedures dealing with this challenging complex anatomic area.Methods Eight fresh, non-formalin-fixed non-silicon-injected adult cadaver heads and five injected formalin-fixed adult cadaver heads were analyzed in this study.Results The anatomical study was focused on the description of the relationships between bony, dural, arachnoid, and neurovascular structures. Surgical implications are described accordingly.Conclusions Detailed anatomical knowledge of this region finds concrete applications in neurosurgical practice since the anterior and middle incisural spaces are often surgically exposed in neoplastic and vascular diseases.

Surgical and prosthetic management of an invasive maxillary odontogenic radicular cyst. Role of osseointegrated implants on bone healing outcomes. 10 year follow-up case report

Objectives: The aim of this report is to visualize the implications which may arise from an untreated maxillary odontogenic radicular cyst. This may initially appear like an ordinary lesion however it reaches an advanced stage of maturation and invasion, therefore surgical implications should help readers consider treatment strategy and timing when observing simple lesions in … Continued

Topographical Variations of Nutrient Foramina in the Dry Adult Scapula: A Cross-sectional Study

Introduction: The scapula is the shoulder girdle bone. Vascularity of this bone may arise from the subscapular and circumflex scapular arteries (on the lateral border), supra-scapular artery (on the superior border), deep branch of the transverse cervical artery (on the medial border), or a branch from the axillary artery (on the costal surface). Nutrient arteries associated with flat bones like the scapula have not received significant research in the past. Aim: To determine the number and location of nutrient foramina on the human dry scapula. Materials and Methods: This descriptive cross-sectional study was conducted in the Department of Anatomy of RG KAR Medical College, Kolkata, West Bengal, India.. The sample was gathered from August 2022 to January 2023. A total of 122 dry adult scapulae were studied (69 right and 53 left), irrespective of age and sex. The data obtained after thorough inspection was tabulated to obtain the results. The International Business Management(IBM) Statistical Package for Social Sciences(SPSS) software tool was used for statistical analysis, and inferences were drawn from the results. Results: The average number of nutrient foramina per scapula was five (ranging from 2 to 10). The most common location of the supraspinous fossa was 30.97%. On the costal surface, most of the nutrient foramina were found directly inferior to the suprascapular notch (30%), and on the dorsal surface, nutrient foramina were identified under the spine of the scapula (23.75%). Nutrient foramina were least present in the peri- glenoid area (15.28%). The Analysis of Variance(ANOVA) test showed homologous subsets between and within the different types of fossae. Conclusion: To maintain the health of the scapula, the nutrient artery must be preserved. Most scapulae had more than one nutrient foramina, located in specific areas on both the dorsal and costal surfaces of the shoulder blade. As a result, orthopaedic surgeons performing scapular surgery place great significance on their topographic understanding of the nutrient foramina. A knowledge of these variations aids surgeons in minimising blood loss during surgical implications around the pectoral girdle or scapular area in living patients.

Incidence of Ossification of Caroticoclinoid Ligament in Dry Adult Human Skulls with its Surgical Implications: A Cross-sectional Study from Telangana Region, India

Introduction: The caroticoclinoid ligament extends from the Anterior Clinoid Process (ACP) to the Middle Clinoid Process (MCP). Occasionally, it gets ossified and forms the caroticoclinoid foramen. Anterior clinoidectomy is a common surgical procedure to treat internal carotid artery aneurysms or pituitary tumours. Abnormal ossification of the caroticoclinoid ligament may lead to intraoperative or postoperative complications as it is not normally present. Aim: To find out the incidence of ossification of the caroticoclinoid ligament in adult human skulls. Materials and Methods: This was an observational crosssectional study that included 100 dry adult human skulls collected from the Department of Anatomy, Gandhi Medical College, Secunderabad; Osmania Medical College, Hyderabad; Bhaskar Medical College, Moinabad, Telangana, India, from January 2021 to February 2023. Adult human skulls with open vault were included. All the skulls were observed and skulls damaged in the clinoid regions were excluded from the study. The skulls were observed for the presence of any ossifications of the caroticoclinoid ligaments and the observations were noted. The qualitative data was presented as number and percentage was calculated. The data was recorded in MS excel version 2021. Results: The incidence of ossification of caroticoclinoid ligament was 8 (8%). The incidence was higher on right-side when compared to the left-side. Bilateral complete ossification of the caroticoclinoid ligament was observed in 2 (2%) skulls; bilateral incomplete ossification was observed in 3 (3%) skulls, unilateral complete ossification was observed in 2 (2%) skulls on the right-side. In one skull 1 (1%), complete ossification was observed on the right-side and incomplete ossification was observed on the left-side. Conclusion: Knowledge of the ossification of the caroticoclinoid ligament is important for neurosurgeons while performing anterior clinoidectomies or skull base surgeries. Radiological confirmation of the ossification of the caroticoclinoid ligament is essential to avoid complications.

Petroclival Clinoidal Folds and Relationships with Arachnoidal Membranes of Anterior and Middle Incisural Spaces: Old Neuroanatomical Terms for a New Neurosurgical Speech in Cadaver Labs with Limited Resources Era. Part II: Free Edge of the Tentorium, Petroclinoid Folds, and Incisural Spaces.

BACKGROUND Anatomical dissections play an irreplaceable role in the training of new generations of effective neurosurgeons, especially when addressing skull base lesions is required.The Authors describe an inter-laboratory dissection study aimed at improving the knowledge of a complex region of the skull base. The anterior and middle incisural spaces are of remarkable anatomical and surgical interest due to complex relationships between bony, dural, arachnoidal, and neurovascular structures. The primary purposes of this study are to describe the anatomy of this region with particular emphasis on the relationships between the anterior margin of the free edge of the tentorium and the sphenoid and petrous bone; to identify surgical implications in many different types of neurosurgical procedures dealing with this challenging, complex anatomic area.METHODS Thirteen anatomical specimens, including five injected specimens, were dissected in this study. In the formalin-fixed specimens, vessels were injected with colored silicone.RESULTS The anatomical study was focused on the description of the relationships between bony dural, arachnoid, and neurovascular structures. Surgical implications are described accordingly.CONCLUSIONS Detailed anatomical knowledge of this region finds concrete applications in neurosurgical practice since the anterior and middle incisural spaces are often surgically exposed in neoplastic and vascular diseases. The high-definition pictures reported in this study could represent useful support to understand the anatomy of this complex region.Finally, our study could provide guidance to neurosurgical centers in which resources are limited that are either planning to establish their own cadaver dissection laboratory or failed to do so because of the supposed high-costs.

Comparison of fMRI language laterality with and without sedation in pediatric epilepsy

Functional MRI is an essential component of presurgical language mapping. In clinical settings, young children may be sedated for the MRI with the functional stimuli presented passively. Research has found that sedation changes language activation in healthy adults and children. However, there is limited research comparing sedated and unsedated functional MRI in pediatric epilepsy patients. We compared language activation patterns in children with epilepsy who received sedation for functional MRI to the ones who did not.We retrospectively identified the patients with focal epilepsy who underwent presurgical functional MRI including Auditory Descriptive Decision Task at Boston Children's Hospital from 2014 to 2022. Patients were divided into sedated and awake groups, based on their sedation status during functional MRI. Auditory Descriptive Decision Task stimuli were presented passively to the sedated group per clinical protocol. We extracted language activation maps contrasted against a control task (reverse speech) in the Frontal and Temporal language regions and calculated separate language laterality indexes for each region. We considered positive laterality indexes as left dominant, negative laterality indexes as right dominant, and absolute laterality indexes <0.2 as bilateral. We defined 2 language patterns: typical (i.e., primarily left-sided) and atypical. Typical pattern required at least one left dominant region (either frontal or temporal) and no right dominant region. We then compared the language patterns between the sedated and awake groups.Seventy patients met the inclusion criteria, 25 sedated, and 45 awake. Using the Auditory Descriptive Decision Task paradigm, when adjusted for age, handedness, gender, and laterality of lesion in a weighted logistic regression model, the odds of the atypical pattern were 13.2 times higher in the sedated group compared to the awake group (Confidence Interval: 2.55–68.41, p-value < 0.01).Sedation may alter language activation patterns in pediatric epilepsy patients. Language patterns on sedated functional MRI with passive tasks may not represent language networks during wakefulness, sedation may differentially suppress some networks, or require a different task or method of analysis to capture the awake language network. Given the critical surgical implication of these findings, additional studies are needed to better understand how sedation impacts the functional MRI blood oxygenation level-dependent signal. Consistent with current practice, sedated functional MRI should be interpreted with greater caution and requires additional validation as well as research on post-surgical language outcomes.

Surgical Implications of Implanted Cardiac Rhythm Devices.

Surgical Implications of Implanted Cardiac Rhythm Devices.

Brainstem Surgery: Functional Surgical Anatomy with the Use of an Advanced Modern Intraoperative Neurophysiological Procedure.

Intraoperative neurophysiology (ION) in brainstem surgery evolved as brainstem surgery advanced.The original idea of brainstem mapping (BSM) is a neurophysiological procedure to locate cranial nerve motor nuclei (CNMN) on the floor of the fourth ventricle. With the introduction of various skull base approaches to the brainstem, BSM is carried out on any surface of the brainstem to expose the safe entry zone to the intrinsic brainstem lesion. It is the modern concept of BSM, a broader definition of BSM. BSM enables to avoid direct damage to the CNMN when approaching the brainstem through the negative mapping region.The corticobulbar tract (CBT) motor evoked potential (MEP) is another ION procedure in brainstem surgery. It enables monitoring of the functional integrity of the whole cranial motor pathway without interrupting surgical procedures. Combined application of both BSM and CBT-MEP monitoring is indispensable for the functional preservation of the CNMN and their supranuclear innervation during the brainstem surgery.In this paper, the neurophysiological aspect of BSM and the CBT-MEP was fully described. Normal anatomical background of the floor of the fourth ventricle and the detail of the CBT anatomy were demonstrated to better understand their clinical usefulness, limitations, and surgical implications derived from ION procedures. Finally, a future perspective in the role of ION procedures in brainstem surgery was presented. The latest magnetic resonance imaging (MRI) technology can allow surgeons to find an "on the image" safe entry zone to the brainstem. However, the role of BSM and the CBT-MEP monitoring in terms of safe brainstem surgery stays unshakable. Special attention was paid for the recent trend of management in diffuse intrinsic pontine gliomas. A new role of BSM during a stereotactic biopsy was discussed.It is the authors' expectation that the paper enhances the clinical application of a contemporary standard of the ION in brainstem surgery and supports safer brainstem surgery more than ever and in the future.

Surgical implications of HIV infection

According to the joint United Nations Programme on HIV/AIDS (UNAIDS), 37.7 million adults and children worldwide were estimated to be living with HIV or acquired immune deficiency syndrome (AIDS) at the end of 2020 [UNAIDS. (2022). http://www.unaids.org . Accessed 30 May 2022]. Most reside in low- and middle-income countries, with approximately 67% in sub-Saharan Africa (SSA). At the end of 2020, the total number of children less than 15years of age living with HIV infection was 2.6 million, of whom 2.3 million (88%) were living in SSA. Aggressive interventions have reduced the annual number of incident (new) HIV infections among children to around 150,000 [UNAIDS. (2022). http://www.unaids.org . Accessed 30 May 2022]. However, paediatric HIV infection remains a pandemic affecting children predominantly in SSA but is also seen in Asia and sporadically elsewhere particularly in areas of civil strife such as is currently the case in Ukraine [War in Ukraine. (2022). https://www.unaids.org/en/War-Ukraine-special . Accessed Apr 2022]. New HIV infections among children declined by more than half (54%) from 2010 to 2020, due mainly to the increased provision of antiretroviral therapy to pregnant and breastfeeding women living with HIV [UNAIDS. (2022). http://www.unaids.org . Accessed 30 May 2022]. These programmes include early identification of HIV infection in pregnant or breastfeeding women through routine HIV testing, provision of antiretroviral therapy (ART) to all HIV-infected women who are pregnant or breastfeeding, provision of antiretroviral prophylaxis to their newborn infants during the first 6-12weeks of life, delivery by elective Caesarean section when indicated, promotion of exclusive breastfeeding, early infancy screening for HIV infection, and initiation of ART in infants with HIV infection. HIV-infected children may require surgery either as an emergency to deal with a life-threatening incidental condition unrelated to HIV infection or for a complication of the disease such as tuberculosis or an aggressive soft tissue infection like necrotising fasciitis. Non-emergency surgical procedures may be required to assist in the diagnosis of an HIV-related condition or to correct a routine surgical problem electively. Surgical conditions associated with HIV infection are described under categories of soft tissue or organ-specific infections requiring drainage or debridement; gastrointestinal tract disease and complications; infections in the perineal area; malignancies and HIV-associated vasculitis. Although surgical outcomes are less favourable in HIV-infected children, pre-operative treatment of coinfections, administration of cotrimoxazole prophylaxis, nutritional support and antiretroviral therapy, together with peri-operative antibiotic prophylaxis have resulted in excellent short-term outcomes [World Health Organization. Consolidated guidelines on the use of antiretroviral drugs for treating and preventing HIV infection: Recommendations for a public health approach, June 201 http://www.apps.who.int/iris/bitstream/10665/85321/1/9789241505727_eng.pdf?ua=1 ; World Health Organization Guideline on when to start antiretroviral therapy and on pre-exposure prophylaxis for HIV, September 2015. http://www.apps.who.int/iris/bitstream/10665/186275/1/9789241509565_eng.pdf?ua=1;Eley et al. in BMC Infect Dis 2:3, 2002;Karpelowsky et al. in Pediatr Surg Int 28:1007-1014, 2012;].

Lymphatic/blood vessel plasticity: motivation for a future research area based on present and past observations.

The lymphatic system plays a significant role in homeostasis and drainage of excess fluid back into venous circulation. Lymphatics are also associated with a number of diseases including lymphedema, tumor metastasis, and various lymphatic malformations. Emerging evidence suggests that lymphatics might have a bigger connection to the blood vascular system than originally presumed. As these two systems are often studied in isolation, several knowledge gaps exist surrounding what constitutes lymphatic vascular plasticity, under what conditions it arises, and where structures characteristic of plasticity can form. The objective of this review is to overview current structural, cell lineage-based, and cell identity-based evidence for lymphatic plasticity. These examples of plasticity will then be considered in the context of potential clinical and surgical implications of this evolving research area. This review details our current understanding of lymphatic plasticity, highlights key unanswered questions in the field, and motivates future research aimed at clarifying the role and therapeutic potential of lymphatic plasticity in disease.

Climate change and surgical implications

Abstract The healthcare sector contributes nearly 5% of the total global carbon emissions, and much of this is attributable to the delivery of surgical services. In this article, we review the impact of surgery on climate change and propose an approach to identifying targets and reducing the global surgical carbon footprint.

Quantitative Comparative Analysis of the Endoscope-Assisted Expanded Retrosigmoid Approach and the Far-Lateral Approach to the Inframeatal Area: An Anatomic Study With Surgical Implications.

The inframeatal area (IFMA) is a complex anatomic region of the posterior cranial fossa. Given its deep-seated location, tumors involving the IFMA represent a surgical challenge. To objectively compare the endoscope-assisted expanded retrosigmoid approach (ERSA) and the far-lateral supracondylar transtubercular approach (FLTA) to address the IFMA. Anatomic dissections were performed on 5 cadaveric heads (10 sides). The ERSAs were performed before and after the FLTAs. The surgical exposure, surgical freedom, and angles of attack to the IFMA were measured and compared for each approach. In addition, 2 illustrative clinical cases are reported. Compared with FLTA, ERSA yielded a nonsignificantly smaller mean area of exposure, whereas FLTA provided a significantly larger mean area of surgical freedom, compared with ERSA ( P = .002). The mean horizontal and vertical angles of attack were significantly different between the approaches. In the vertical plane, FLTA yielded the broadest angle of attack at the root entry zone of the lower cranial nerves (CN; P < .004), whereas ERSA did so at the dural entry zone of CN VII/VIII ( P = .006). In the horizontal plane, FLTA achieved its broadest angle of attack at the root entry zone of the lower CNs ( P = 1.83) while ERSA at the dural entry zone of CN VII/VIII ( P = .37). ERSA and FLTA granted a comparable exposure with the IFMA. Although FLTA may afford a larger area of surgical freedom, ERSA may be a suitable alternative to approach the IFMA, particularly to reach the most medial and superior aspects of this region. Conversely, FLTA may facilitate access to more caudally targets.

Microsurgical anatomy of the dorsal clinoidal space: implications for endoscopic endonasal parasellar surgery.

The clinoidal venous space dorsal to the internal carotid artery (ICA) has not been well studied given its inaccessibility due to obstruction by the ICA during transcranial surgery. The evolution of endoscopic endonasal surgery has provided a new perspective into the clinoidal space and a new route for paraclinoidal lesions. Understanding the dorsal clinoidal space (DCS) is vital in planning and performing endoscopic endonasal surgery in the parasellar region. A detailed and precise description of the DCS from the endonasal perspective has not yet been provided. The authors' goal in this study was to delineate the microsurgical anatomy of the DCS from an endoscopic endonasal perspective, emphasizing its surgical implications when treating invasive pituitary adenomas and other parasellar lesions. An endoscopic endonasal transsellar approach was performed in 15 silicone-injected postmortem heads. Afterward, the sellar region was dissected through a transcranial approach using magnification ×3 to ×40 microscopy. The osseous, dural, and arterial relationships of the DCS and its architecture were investigated. The DCS's length, width, and depth were measured and its anatomical variations recorded. The DCS was identified in 90% of the specimens, and in most cases, its shape was a narrow rectangular pyramid, with its base oriented toward the sphenoid sinus and its apex toward the posterior clinoid process. It is delimited superiorly by the distal ring, inferiorly by the medial aspect of the proximal dural ring or caroticoclinoid ligament, laterally by the clinoidal ICA, and medially by the superior continuation of the medial wall of the cavernous sinus. The width, height, and length of the DCS were 4 ± 1, 4.5 ± 1.5, and 7 ± 2 mm, respectively. A fenestrated caroticoclinoid ligament is a potential route for tumor invasion from the cavernous sinus into the DCS. This report provides important anatomical descriptions of the DCS from endoscopic endonasal and transcranial perspectives that may facilitate the space's safe exposure for the removal of invasive adenomas, increasing total resection rates and minimizing the risk of injury to neurovascular structures.

ODP416 Increased Ovarian Volume in Young Girls: A Marker of Impending Hyperandrogenism or Normal Variant?

Abstract Ovarian volume increases with age in childhood with reported volumes from 0.6 cm 3 in neonates to approximately 6 cm 3 by 12 years old. There are no precise normal ranges defined based on age or Tanner stage in childhood; therefore, interpretation of ovarian volume can be challenging. The surgical and medical implications of ovarian enlargement are important as it can help predict ovarian torsion. It has been reported that a higher ovarian volume ratio (OVR) (ratio of larger to contralateral ovary) may be a strong predictor of ovarian torsion. A study evaluating premenarchal girls 3-14 years old showed OVR of 7.6 Vs 1.4 in those with and without torsion respectively. There is also an association between current or eventual development of hyperandrogenism and enlarged ovaries in adolescents. Seven girls, five to nine years old presented for care between 2013 and 2021 with at least one ovary large for pubertal status (volume ranging from 6 to 38 mL). Of these, 6 had bilateral enlargement. Presentation was for abdominal pain from ovarian torsion (5/7) or concerns for early puberty (2/7). Family history of PCOS was positive in 4/7. All girls were prepubertal or in early puberty (Tanner stage I-II for breast and pubic hair). All had normal body mass indices (BMI), none had reported hirsutism, acne or stigmata of Mc-Cune Albright syndrome. Pelvic ultrasound revealed large ovaries without discrete ovarian cysts or masses, 2/7 had decreased blood flow with one of these having heterogeneity related to prior torsion. Thyroid function tests, prolactin, gonadotropins, androgen levels and tumor markers were normal when measured. Bone age was checked and normal in five cases. Follow up ranged from 0-8 years, none required pubertal suppression for progressive precocious puberty. One case was diagnosed with PCOS at age 17 years after an initial presentation of ovarian torsion. PCOS is associated with oligo/anovulation and a risk for development of metabolic syndrome. Earlier detection of PCOS, particularly in the early pubertal age group may alter the trajectory of the complications with close monitoring potentially decreasing eventual metabolic risks. Since PCOS is associated with larger ovarian volumes (&amp;gt;10mL in the adolescent population), detection of this enlargement in early puberty may portend later development of PCOS. It is also conceivable that premenarchal girls presenting with ovarian enlargement may signify a specific hyperandrogenic phenotype. While it is possible that larger ovarian volumes are variants of normal, larger retrospective studies and ideally, prospective, long term follow up investigations are required to determine a relationship between them and eventual hyperandrogenic and metabolic phenotypes. Presentation: No date and time listed