Bony Margins Research Articles

Forearm range of motion in Allosaurus fragilis (Dinosauria: Theropoda)

ABSTRACT Forelimb bones of the Early Jurassic theropod Allosaurus fragilis were digitally manipulated based on three-dimensional (3D) digital models. Bony articular surface margins were used as limits to determine the range of motion (ROM) for each forelimb joint, and to test functional hypotheses of forelimb usage. We discuss the effects of palaeopathology at the right shoulder joint on inferring ROM in the forelimb of Allosaurus. It is considered that the glenoid aberration of this sub-adult specimen occurred in early ontogeny and lasted for a long period of time, affecting to varying degrees the development of the whole right arm (but not the manus). The relatively large ranges of extension and flexion of manual joints indicate well grasping ability consistent with early-diverging theropods. The limited ROM of the shoulder joints of Allosaurus suggests that the forelimbs were predominantly prey-acquiring but could go no further forward, indicating that the first contact with prey was made by the mouth. The manus could assist in grasping prey on the chest or below the neck or hooking objects.

Patient-specific guides for consistently achieving R0 bone margins after resection of primary malignant bone tumors of the pelvis

AimsPrimary malignant bone tumor of the pelvis is an uncommon lesion, the resection of which via freehand osteotomy is subject to inaccuracy due to its three-dimensional anatomy. Patient-Specific Guides (PSG), also called Patient-Specific Instruments (PSI) are essential to ensure surgical planning and resection adequacy. Our aim was to assess their use and effectiveness.MethodsA monocentric retrospective study was conducted on 42 adult patients who underwent PSG-based resection of a primary malignant bone tumor of the pelvis. The primary outcome was the proportion of R0 bone margins. The secondary outcomes were the proportion of overall R0 margins, considering soft-tissue resection, the cumulative incidence of local recurrence, and the time of production for the guides. A comparison to a previous series at our institution was performed regarding histological margins.ResultsUsing PSGs, 100% R0 safe bone margin was achieved, and 88% overall R0 margin due to soft-tissue resection being contaminated, while the comparison to the previous series showed only 80% of R0 safe bone margin. The cumulative incidences of local recurrence were 10% (95% CI: 4–20%) at one year, 15% (95% CI: 6–27%) at two years, and 19% (95% CI: 8–33%) at five years. The median overall duration of the fabrication process of the guide was 35 days (Q1–Q3: 26–47) from the first contact to the surgery date.ConclusionsPatient-Specific Guides can provide a reproducible safe bony margin.

Assessment of the bony resection margin distance in bone-invasive oral cancer using laser-induced breakdown spectroscopy

ObjectivesInadequate resection margins of less than 5 mm impair local tumor control. This weak point in oncological safety is exacerbated in bone-infiltrating tumors because rapid bone analysis procedures do not exist. This study aims to assess the bony resection margin status of bone-invasive oral cancer using laser-induced breakdown spectroscopy (LIBS).Materials and methodsLIBS experiments were performed on natively lasered, tumor-infiltrated mandibular cross-sections from 10 patients. In total, 5,336 spectra were recorded at defined distances from the tumor border. Resection margins < 1 mm were defined as very close, from 1–5 mm as close, and > 5 mm as clear. The spectra were histologically validated. Based on the LIBS spectra, the discriminatory power of potassium (K) and soluble calcium (Ca) between bone-infiltrating tumor tissue and very close, close, and clear resection margins was determined.ResultsLIBS-derived electrolyte emission values of K and soluble Ca as well as histological parameters for bone neogenesis/fibrosis and lymphocyte/macrophage infiltrates differ significantly between bone-infiltrating tumor tissue spectra and healthy bone spectra from very close, close, and clear resection margins (p < 0.0001). Using LIBS, the transition from very close resection margins to bone-infiltrating tumor tissue can be determined with a sensitivity of 95.0%, and the transition from clear to close resection margins can be determined with a sensitivity of 85.3%.ConclusionsLIBS can reliably determine the boundary of bone-infiltrating tumors and might provide an orientation for determining a clear resection margin.Clinical relevanceLIBS could facilitate intraoperative decision-making and avoid inadequate resection margins in bone-invasive oral cancer.

Sagittal en bloc resection of thoracolumbar tumours: a report of thirty one cases.

To develop a novel classification of sagittal en bloc resection (SEBR) based on anatomical locations for thoracolumbar spine tumors and assess the clinical outcomes of this surgical procedure. 31 patients with thoracolumbar tumours treated with SEBR were enrolled in this study. The individualized surgical strategy was adopted based on our surgical classification. Demographics, perioperative outcomes, complications and postoperative outcomes were assessed. Based on our surgical classifications, patients were divided into four types. All bony resection margins were negative, wide resection was achieved in 25 patients, marginal resection in four, and intralesional resection in two. 18 patients underwent anterior reconstruction. Complications were encountered in five patients, and instrumentation failure occurred in one patient. The median follow-up was 24 (range, 6-72) months and recurrence was found in only one patient. SEBR is a safe and effective surgical procedure for patients with thoracolumbar spinal tumours in specific anatomical locations. The proposed surgical classification covers all SEBR types and is easy to apply, it may assist surgical decision-making in patients with spinal tumours.

Does the use of intraoperative frozen section of bone marrow from the cut end of the mandible help assess the adequacy of bone margins following mandibulectomy for oral cancer?

The adequacy of the cut end of the mandible following a segmental mandibulectomy done for oral cancer intraoperatively is at times assessed using a frozen section (FS)of the bone marrow (BM)at the cut ends. The study aimed to assess its utility to guide the intraoperative decision on the adequacy of bony margins. All patients with oral squamous cell carcinoma (OSCC)who underwent segmental mandibulectomy from January 2012 to December 2021 at our institute and for whom intraoperative FS of BM was utilized were included. We analyzed the sensitivity, specificity, and positive and negative predictive value (PPV,NPV) of this in predicting positive bone margins. A total of 457 patients were included in the study. The majority of the cases were per premium cases (n = 372, 81.4%). The median age of the cohort was 52 years (range: 22-80 years). Most patients had T4 disease (n = 406, 88.8%). On FS, BM was positive in only 18 patients (3.9%) for whom the bone margin was revised. BM biopsy report in the final histopathology was positive in 12 patients (2.2%). The sensitivity, specificity PPV, and NPV were 52.3%, 98.65%, 64.7%, and 97.7% respectively. No factors predicting BM positivity on FS could be identified in this cohort. The BM FS was positive in only a small percentage of patients, and it helped in reducing the bone margin positivity rate from 3.9% to 2.2% only. Hence the intraoperative BM FS seems to have limited utility as seen from our study.

Customised pre-operative cranioplasty to achieve maximal surgical resection of tumours with osseous involvement-a case series.

Surgical resection with bony margins would be the treatment of choice for tumours with osseous involvement such as meningiomas and metastasis. By developing and designing pre-operative customised 3D modelled implants, the patient can undergo resection of meningioma and repair of bone defect in the same operation. We present a generalisable method for designing pre-operative cranioplasty in patients to repair the bone defect after the resection of tumours. We included six patients who presented with a tumour that was associated with overlying bone involvement. They underwent placement of customised cranioplasty in the same setting. A customised implant using a pre-operative imaging was designed with a 2-cm margin to allow for any intra-operative requirements for extending the craniectomy. Six patients were evaluated in this case series. Four patients had meningiomas, 1 patient had metastatic breast cancer on final histology, and 1 patient was found to have an intra-osseous arteriovenous malformation. Craniectomy based on margins provided by a cutting guide was fashioned. After tumour removal and haemostasis, the cranioplasty was then placed. All patients recovered well post-operatively with satisfactory cosmetic results. No wound infection was reported in our series. Our series demonstrate the feasibility of utilising pre-designed cranioplasty for meningiomas and other tumours with osseous involvement. Following strict infection protocols, minimal intra-operative handling/modification of the implant, and close follow-up has resulted in good cosmetic outcomes with no implant-related infections.

Inferior temporal quadrantanopia associated with pituitary adenomas and a potential mechanism of excessive optic nerve bending.

Pituitary adenomas show typical visual field defects that begin superiorly and progress inferiorly. The cause of atypical visual field defects that start inferiorly remains unclear. This study aimed to understand this phenomenon using magnetic resonance imaging (MRI). A total of 220 patients with pituitary adenomas underwent a visual field assessment of both eyes. Preoperative visual fields were assessed and classified into two types: superior quadrantanopia (typical) and inferior quadrantanopia (atypical). Several parameters related to tumor characteristics and optic nerve compression were evaluated using MRI. Of the 440 eyes examined, 174 (39.5%) had visual field defects. Of these, 28 (16.1%) had typical and 11 (6.3%) had atypical visual field defects. Patient age, tumor size, degree of cavernous sinus invasion, tumor pathology, and intratumor bleeding were similar between the two groups. The angle formed by the optic nerve in the optic canal and in the intracranial subarachnoid space at the exit of the optic canal (degree of optic nerve bending) was significantly larger in the atypical group than in the typical group (42.6° vs. 23.9°, P = 0.046). In some pituitary adenomas, visual field defects begin inferiorly. This may be caused by optic nerve compression on the superior surface by the bony margin of the optic canal exit. Therefore, pituitary adenomas should be considered in patients with atypical visual field defects.

Morphometric and clinical comparison of MRI-based synthetic CT to conventional CT of the hip in children.

MRI-based synthetic CT (sCT) generates CT-like images from MRI data. To evaluate equivalence, inter- and intraobserver reliability, and image quality of sCT compared to conventional (cCT) for assessing hip morphology and maturity in pediatric patients. We prospectively enrolled patients <21 years old with cCT and 3T MRI of the hips/pelvis. A dual-echo gradient-echo sequence was used to generate sCT via a commercially available post-processing software (BoneMRI v1.5 research version, MRIguidance BV, Utrecht, NL). Two pediatric musculoskeletal radiologists measured seven morphologic hip parameters. 3D surface distances between cCT and sCT were computed. Physeal status was established at seven locations with cCT as reference standard. Images were qualitatively scored on a 5-point Likert scale regarding diagnostic quality, signal-to-noise ratio, clarity of bony margin, corticomedullary differentiation, and presence and severity of artifacts. Quantitative evaluation of Hounsfield units (HU) was performed in bone, muscle, and fat tissue.Inter- and intraobserver reliability were measured by intraclass correlation coefficients. The cCT-to-sCT intermodal agreement was assessed via Bland-Altman analysis. The equivalence between modalities was tested using paired two one-sided tests. The quality parameter scores of each imaging modality were compared via Wilcoxon signed-rank test. For tissue-specific HU measurements, mean absolute error and mean percentage error values were calculated using the cCT as the reference standard. Thirty-eight hips in 19 patients were included (16.6 ± 3 years, range 9.9-20.9; male = 5). cCT- and sCT-based morphologic measurements demonstrated good to excellent inter- and intraobserver correlation (0.77<ICC<0.98). Measurements were statistically equivalent (P< 0.05), with average intermodal differences <2°. Mean surface distance between cCT and sCT was 0.23 ± 0.18mm. Accuracy to determine physeal maturity status by sCT was 98.4% (242/246, 95% CI 96.0-99.6). No significant differences were found on overall diagnostic quality, bony margin clarity, corticomedullary differentiation, and artifacts between sCT and cCT; signal-to-noise ratio was higher on sCT (P< 0.001). HU were within reference values on both sCT and cCT. sCT is equivalent to cCT for the assessment of hip morphology, physeal status, and radiodensity assessment in pediatric patients.

Langerhans cell histiocytosis involving the temporal bone with destruction and subsequent reossification of the bony labyrinth boundaries.

With an incidence between 1-9/100 000 per year, Langerhans cell histiocytosis (LCH) is a rather rare disease from the hemato-oncologic disease spectrum (Hayes et al. 2009). The tumorlike disease with proliferation of histiocytic cells may manifest as localized to one organ or disseminated with infiltration of a wide variety of organs. Approximately 25-30 % of these cases show involvement of the temporal bone (Ni et al. 2017). With vertigo persisting for three years, chronic mastoiditis, and acute progressive hearing loss bilaterally (r > l) for three weeks, a 41-year-old woman presented at an emergency department. The DVT showed extensive bony destruction of large parts of the temporal bone on both sides, involving the vestibular organ, the cochlea, and the internal auditory canal. To confirm the suspicion of a systemic inflammatory process, a PE was performed from the mastoid with bioptic confirmation of an LCH. Systemic therapy was initiated. Post-therapeutic imaging showed almost complete remission with reossification of the preexisting defect zones and the internal auditory canal and labyrinth structures again showed bony margins. Clinically, there was an improvement of the vegetative symptoms with remaining bilateral sensorineural hearing loss. LCH of the temporal bone is a rare and often misdiagnosed disease due to its nonspecific clinical presentation. Awareness of temporal bone LCH and its occurrence in adults is essential for accurate and consistent diagnosis. · LCH is a rather rare disease from the hemato-oncological spectrum. · Affection of the temporal bone, especially such an extensive one (as in this case report), is rather atypical in adulthood. · Use of systemic therapy resulted in remission. · There was complete reossification of the osseous structures post-therapy. · A cochlear implant was able to be implanted to compensate for hearing loss.

How Does Customized Cutting Guide Design Affect Accuracy and Ergonomics in Pelvic Tumor Resection? A Study in Cadavers.

Customized cutting guides are technical aids that make primary pelvic bone tumor resection safer and more reliable. Although the effectiveness of such devices appears to be widely accepted, their conception and design remain varied. Two main designs have been reported: the heavier block-type customized cutting guides and the lighter patch-type customized cutting guides. As recent tools, there must be more evidence regarding the impact of design on their accuracy and ergonomics. Thus, an evaluation of their respective performances appears warranted. In a cadaver model, we assessed whether (1) a thinner, patch-type customized cutting guide design results in resections that are closer to the planned resections than the heavier block-type customized cutting guides, and (2) the patch-type customized cutting guide design is more ergonomic than the block-type customized cutting guide with improved usability in surgery (in terms of bulkiness, ease of placement, primary and secondary stability, and stability during cutting). We conducted an experimental study involving five fresh whole-body anatomic specimens (three women and two men with a median age of 79 years and median weight of 66 kg) by simulating six virtual tumors in three areas according to the Enneking classification (Zones I: iliac wing, II: periacetabular area, and I and IV: sacroiliac joint area). We compared the impact of the customized cutting guide's design on performance in terms of the resection margin accuracy using CT scan analysis (deviation from the planned margin at the closest point and the maximum deviation from the planned margin) and the intraoperative ergonomic score under conditions simulating those of an oncologic resection of a bone tumor (with a range of 0 to 100, with 100 being best). The patch customized cutting guides performed slightly better than the block customized cutting guides regarding deviation from the planned margin at the closest point, with median values of 1 mm versus 2 mm (difference of medians 1 mm; p = 0.02) and maximum deviation from the planned margin of 3 versus 4 mm (difference of medians 1 mm; p = 0.002). In addition, the patch design was perceived to be slightly more ergonomic than the block design, with a 92% median score versus 84% for the block design (difference of medians 8%; p = 0.03). We observed an equivalence in performance regarding accuracy and ergonomics, with slight advantages for patch customized cutting guides, especially in complex zones (Zone I and IV). Owing to a small cohort in a cadaver study, these results need independent replication. The patch-type customized cutting guide with thinner contact spots to the bone in specific areas and less soft tissue dissection might offer an advantage over a larger block design for achieving negative oncologic bony margins, but it does not address issues of soft tissue margins.

Mesenchymal Stem/Stromal Cells: Immunomodulatory and Bone Regeneration Potential after Tumor Excision in Osteosarcoma Patients.

Osteosarcoma (OS) is a type of bone cancer that is derived from primitive mesenchymal cells typically affecting children and young adults. The current standard of treatment is a combination of neoadjuvant chemotherapy and surgical resection of the cancerous bone. Post-resection challenges in bone regeneration arise. To determine the appropriate amount of bone to be removed, preoperative imaging techniques such as bone and CT scans are employed. To prevent local recurrence, the current standard of care suggests maintaining bony and soft tissue margins from 3 to 7 cm beyond the tumor. The amount of bone removed in an OS patient leaves too large of a deficit for bone to form on its own and requires reconstruction with metal implants or allografts. Both methods require the bone to heal, either to the implant or across the allograft junction, often in the setting of marrow-killing chemotherapy. Therefore, the issue of bone regeneration within the surgically resected margins remains an important challenge for the patient, family, and treating providers. Mesenchymal stem/stromal cells (MSCs) are potential agents for enhancing bone regeneration post tumor resection. MSCs, used with scaffolds and growth factors, show promise in fostering bone regeneration in OS cases. We spotlight two MSC types-bone marrow-derived (BM-MSCs) and adipose tissue-derived (ASCs)-highlighting their bone regrowth facilitation and immunomodulatory effects on immune cells like macrophages and T cells, enhancing therapeutic outcomes. The objective of this review is two-fold: review work demonstrating any ability of MSCs to target the deranged immune system in the OS microenvironment, and synthesize the available literature on the use of MSCs as a therapeutic option for stimulating bone regrowth in OS patients post bone resection. When it comes to repairing bone defects, both MB-MSCs and ASCs hold great potential for stimulating bone regeneration. Research has showcased their effectiveness in reconstructing bone defects while maintaining a non-tumorigenic role following wide resection of bone tumors, underscoring their capability to enhance bone healing and regeneration following tumor excisions.

The role of potassium in depth profiling of the tumor border in bone-invasive oral cancer using laser-induced breakdown spectroscopy (LIBS): a pilot study

PurposeMicroscopic tumor spread beyond the macroscopically visible tumor mass in bone represents a major risk in surgical oncology, where the spatial complexity of bony resection margins cannot be countered with rapid bone analysis techniques. Laser-induced breakdown spectroscopy (LIBS) has recently been introduced as a promising option for rapid bone analysis. The present study aimed to use LIBS-based depth profiling based on electrolyte disturbance tracking to evaluate the detection of microscopic tumor spread in bone.MethodsAfter en bloc resection, the tumor-infiltrated mandible section of a patient’s segmental mandibulectomy specimen was natively investigated using LIBS. Spectral and electrolytic depth profiles were analyzed across 30 laser shots per laser spot position in healthy bone and at the tumor border. For the histological validation of the lasered positions, the mandibular section was marked with a thin separating disc.ResultsSolid calcium (Ca) from hydroxyapatite and soluble Ca from dissolved Ca can be reliably differentiated using LIBS and reflect the natural heterogeneity of healthy bone. Increased potassium (K) emission values in otherwise typically healthy bone spectra are the first spectral signs of tumorous bone invasion. LIBS-based depth profiles at the tumor border region can be used to track tumor-associated changes within the bone with shot accuracy based on the distribution of K.ConclusionDepth profiling using LIBS might enable the detection of microscopic tumor spread in bone. In the future, direct electrolyte tracking using LIBS should be applied to other intraoperative challenges in surgical oncology to advance rapid bone analysis by spectroscopic–optical techniques.

Long term follow-up results of enucleation as the definitive treatment for melanocytic neuroectodermal tumour of infancy and a review on its treatment.

Melanotic Neuroectodermal tumour of Infancy (MNTI) is a rare entity of pigmented neoplasms of head and neck region. It predominantly occurs within the first year of life. The authors present enucleation as the definitive surgical treatment, with reference to the five departmental cases of MNTI with no recurrence at 5years and 1year of follow-up of other 4 cases. Five cases of MNTI (age group of 2.5months-7 months) presented to our department as a large bluish-brown non tender swelling protruding into the oral cavity. Radiologic imaging revealed a well-circumscribed solid-cystic enhancing lesion causing elevation of orbit and nasal obliteration in maxillary region and causing buccolingual expansion in mandible. The tumor was enucleated without any bony margin. Histopathological and immunohistochemical evaluation (EMA, Pan Cytokeratin, HMB45, S100, p53, ki67) were done. Patients were followed up at regular intervals and had no recurrence at mean 3years follow-up. A detailed mention of surgical pearls, differential diagnosis and a brief literature review are also done. MNTI is a pigmented neoplasm that occurs in infants and in head and neck region mostly involves the upper alveolus and maxilla, followed by skull and mandible. Incisional biopsy is needed to confirm the tumour and rule out other malignant round cell tumours. Enucleation of the lesion is necessary without the need for any extra bony margin removal. Close long term follow up is necessary. Conservative surgical approach is usually the best first choice for MNTI treatment.

Posteroinferior relevant scapular neck offset in reverse shoulder arthroplasty: key player for motion and friction-type impingement in a computer model.

Range of motion (ROM) and prevention of notching remain a challenge for reverse shoulder arthroplasty (RSA). Both may be affected by the morphology of the scapula. The purpose of this study was to define anteroinferior (a) and posteroinferior (p) relevant scapular neck offset (RSNO) and to examine the hypothesis that pRSNO is significantly smaller than aRSNO, and influences rigid body motion (RBM). Adapting glenosphere implantation strategies may therefore be of value. In this computer model study, we used deidentified computed tomographic scans of 22 patients (11 male and 11 female; mean age: 72.9 years) with massive cuff tears without joint space narrowing. Eight RSA glenoid configurations were tested with a constant neck-shaft angle (145°). Two baseplate types (25 mm; 25 + 3 mm lateralized) and 4 glenospheres (GS) (36 mm; 36 +2 mm of eccentricity; 39 mm; 39 + 3 mm) were used. RSNO was defined as the standardized measurement of the horizontal distance from the inferior extent of the GS to the bony margin of the scapula after baseplate positioning (flush to inferior glenoid extent; neutral position: 0° inclination and 0° version-both software computed). There was a highly significant difference between pRSNO and aRSNO for both genders (P<.001). pRSNO was always smaller than aRSNO. pRSNO was strongly correlated with external rotation (ERO: 0.84) and extension (EXT: 0.74) and moderately correlated with global ROM (GROM: 0.68). There was a moderately strong correlation between aRSNO and internal rotation (IRO: 0.69). pRSNO was strongly correlated with aRSNO, EXT, ERO, IRO, adduction (ADD) and GROM (0.82, 0.72, 0,8, 0.71, 0.82, 0.76) in female patients and with EXT and ERO (0.82, 0.89) in male patients. The median pRSNO allowing for at least 45° ERO and 40° EXT was 14.2 mm for men and 13.8 mm for women. For all patients and models, pRSNO ≥14 mm increased EXT, ERO, and GROM significantly compared with pRSNO <14 mm (P<.001). The combination of lateralization and inferior overhang (eccentricity) led to the most significant increase of pRSNO for each GS size (P<.001). This is one of the first RSA modeling studies evaluating nonarthritic glenoids of both genders. The lateral scapular extent to glenoid relationship is asymmetric. pRSNO is always smaller than aRSNO for both genders and was a critical variable for EXT and ERO, demonstrating additional strong correlation with aRSNO, IRO, ADD, and GROM in female patients. pRSNO ≥14 mm was a safe value to prevent friction-type impingement. Combining increased glenosphere size, lateralization, and inferior overhang gives the best results in this computer-simulated setting.

ODP294 An Unusual Case of Endocrine Disruption as an Early Expression of Low Grade Intra Sellar Chordoma

Abstract A 53y/o male patient presented to his PCP with fatigue and diagnosed with low testosterone and was started on testosterone. P ituitary labs were not checked then. After 6-8 weeks he was referred to neurology for new onset vision problems, diplopia, and daily headaches. MRI brain then showed a sellar mass of 2.4×2.6×2.7 cm with sphenoid sinus extension and bony thinning alongthe margins of the sella turcica which was nearly imperceptible. On testosterone replacement, biochemical assessment of anterior pituitary function showed total testosterone: 836 (264–916 ng/dl), Free Testosterone: 32.6 (2.5-9.5 ng/ml), LH&amp;lt;0.1 (1.2-8.6 IU/L), FSH 0.2 (1.5-12.4 IU/L), Prolactin 18 (4-26 ng/ml), TSH 0. 03(0.4-4.1 UIU/ml), FT4 0.63 (0.8-1.9ng/dl), IGF 188 (55-186 ng/ml), ACTH&amp;lt;5 (10-65 pg/ml), Cortisol&amp;lt;1 (4.8-19.5 ug/dl). Endoscopic endonasal surgery was performed with complete removal of the tumorand abdominal fat graft harvest. Histopathological findings confirmed well differentiated low grade chordoma. Post operatively he improved, and headaches and visual disturbances resolved. Patient was sent home on Hydrocortisone 10mg am/5mg pm. Then, he presented to our endocrine clinic for initial hormonal evaluation. On steroid replacement, endocrine testing was repeated four weeks post-surgery. Labs showedTSH 2. 070 (0.4-4.1 UIU/ml), FT4 1.16 (0.8-1.9ng/dl), FSH&amp;lt;0.3(1.5-12.4 IU/L), LH&amp;lt;0.3(1.2-8.6 IU/L), Prolactin 26 (4 -26), ACTH 19.6 (10-65 pg/ml), Cortisol 7 (4.8-19.5 ug/dl), IGF-1 129 (55-186 ng/ml). Four months after the surgery, patient passed the cosyntropin stimulation test and was able to wean off the hydrocortisone replacement. Post-op repeat MRI brain showed complete resolution of the clivial mass. Current, he remains stable with regular follow ups. The most common presenting symptoms of a sellar chordoma include visual problems and uncommonly hypopituitarism. Our case shows that non-adenomatous tumors can still challenge us with the original presentation as an endocrine deficit. In a case series, only one of nine cases had presented with pituitary dysfunction. Our patient was noted to have hypogonadism and started on testosterone supplementation without further investigation. It is important to evaluate hormonal status in all pituitary masses and recognize that some cases of sellar chordoma can present with endocrine dysfunction as the initial manifestation. In our case, endocrine function of the patient returned to normal once the pituitary compression from chordoma was eliminated. Presentation: No date and time listed

Surgical Margins in 3D Planned Mandibular Resections for Squamous Cell Carcinomas of the Oral Cavity.

Three-dimensional (3D) planned mandibular resections using cutting guides and preplanned plates are now widely used in oncological surgery. The main advantages are the gain of time, precision, and esthetic outcomes. The drawbacks include costs, time for planning, and printing the surgical tools. This time between the radiological data and the surgery may allow tumor progression, rendering the custom-made guides useless. There is no consensus regarding surgical margins that should be planned to ensure a safe oncologic outcome. The purpose of this retrospective study is to evaluate if the planned bony margins are adequate. Inclusion criteria were: Squamous cell carcinomas of the anterior and lateral floor of mouth with mandibular invasion (T4); mandibular resection using 3D planning and cutting guides. Between June 2015 to December 2019, 16 patients met the criteria. The time between the planning and the surgery was recorded. The authors decided to use a margin of at least 1 cm on the preoperative computerized tomography scans on each side of the tumors in our planning for all patients. The authors then measured the distance of the bone resection on the pathological specimen. All 16 patients had safe bone surgical margins (R0). The average time from the scanners used for the planning to the surgery was 33 days. All the cutting guides could be used. The pathology examination showed safe oncological margins and no patients required further resection. A 1 cm margin during 3D planning for mandibular resections with 3D printed cutting guides, in patients with T4 Squamous Cell Carcinomas can therefore be considered safe.

Does the use of a "wrap" in three-dimensional surgical planning influence the bony margin status of benign and malignant neoplasms of the oral, head, and neck region? An initial investigation.

Three-dimensional surgical planning (3-DSP) is becoming commonplace in the management of benign and malignant disease for oral and maxillofacial surgery practice within the last decade. Surgeons utilize a virtual "wrap" to preoperatively delineate and define maxillofacial tumor resection margins. The investigators hypothesized that the use of a wrap is a predictable method to obtain negative bony margins. The investigators implemented a retrospective chart review. The sample was composed of patients over the age of 18 treated at John Peter Smith Health Network and Parkland/UT Southwestern Medical Center who obtained 3-DSP for the pathology of the head and neck, involving the bone, with a virtual wrap utilized for bony margins. The proportion of cases was calculated, descriptive statistics were reported, and binomial exact calculation was performed for confidence intervals. The primary variable analyzed was bony margin status on final histopathology, involved or uninvolved, based on the pathology report. The sample was composed of 39 cases, one of which was excluded due to aborting the preplanned 3-DSP. Of the 38 included cases, one had involved bony margin on final histopathology (2.6%; 95% confidence limits, 0.1%, 13.8%). There were 16 malignant cases (42%) and 22 benign cases (58%). When stratified by pathology, 1 out of the 16 malignant cases (6.3%; 95% confidence interval, 0.2%, 30%) and 0 out of the 22 benign cases (95% confidence interval, 0%, 15.4%) had an involved bony margin on final histopathology. The results of this preliminary study suggest three-dimensional surgical planning with wrap margins is a predictable method to obtain negative bony margins in benign and malignant disease of the maxillofacial complex. Further studies will focus on compiling prospective data to solidify the accuracy and predictability of using a wrap to obtain negative bony margins.

Clinical, Radiological and Histopathologic Correlation in Determining Safe Margins Following Resection of Benign Pathologic Lesion: Is Resection With Healthy Margins of 1-1.5 cm Necessary?

The aim of the study was to discuss linear resection margins including tumor–bone interface of the encountered benign odontogenic/nonodontogenic lesions and how bony margins can be clinically and radiographically evaluated to act as a guide for treatment recommendations.

The Open Book Genioplatsy Technique: A Modification.

Genioplasty is a versatile procedure in the repertoire of a maxillofacial surgeon since the time it was conceptualized by Trauner and Obwegeser in 1957.1 The chin improves the facial profile and renders a definition to the jaw. An aligned and proportionate chin adds ample aesthetic value and youthfulness to the face. In addition, it influences the apparent length of the face. Genioplasty holds the potential to alter the dynamics of facial harmony with minimal effort.2 Failure to perform a much required genioplasty can jeopardize the outcome of hours of an otherwise successful major orthognathic or cosmetic surgery.3 The slope and nature of rotation of the osteotomized segments dictate the extent of vertical and horizontal changes.4 In this article, we attempt to introduce a modification to the existing plethora of genioplasty techniques, particularly aimed to rectify a short square jaw into a feminine one. This technique comprises two conventional oblique osteotomies that split the chin into two components, superior and inferior. A margin of 5 mm is kept superiorly from the root tip, inferiorly from the lower border of mandible, and laterally from the mental foramen. Additional stripping of muscles along the lower border of the mandible ensures adequate mobility of the osteotomized inferior segment. The osteotomized segment is rotated outward and downward at an angle of about 30 to 40 degrees, wherein the tip of the inferior osseous segment is regarded as the prominence of the newfound mentum and the anterior surface of the chin becomes the lower border of the mandible (Fig. 1). The osseous segments are secured using two four-hole, 2.0-mm titanium plates (Fig. 2). Bony margins are smoothed. Hemostasis is achieved. Closure is performed done using 4-0 Vicryl sutures. A 1-year pictorial and radiographic follow-up is charted. The same substantiates the successful outcome of the procedure in terms of desired vertical increment, horizontal augmentation, a feminine round chin with a pointy upheal, and desired labiomental fold.Fig. 1.: Schematic representation of the open book genioplasty technique, in which point A becomes the newfound chin prominence, B becomes the lower border of the mandible, and C is the thickness of the mandible seen upon rotation.Fig. 2.: Osseous segment secured using titanium plates and screws depicting an open book fixation.The design of this open book osteotomy can be deemed ideal for a patient with an existing broad chin who desires a sharper, more feminine one. We have so far performed this procedure on female patients, who require a horizontal advancement of about 10 to 13 mm. The greatest advantage lies in negating a step formation along the lower border of the mandible, contributing to a smooth jawline. The downward rotation of the inferior segment helps acquire additional length, thus leading to a vertical increment in the lower half of the face. The possibility of a dual-plane augmentation makes this technique a versatile one. The thickness of the mentum is a vital consideration, as the osseous volume directly translates to the extent of advancement that can be achieved. In our vast clinical experience, the proposed open book genioplasty technique has had gratifying results with the desired osseous and soft-tissue outcomes in female patients with a short, square chin. ACKNOWLEDGMENT This study conformed to all guidelines of the Declaration of Helsinki. DISCLOSURE The authors have no financial interest to declare in relation to the content of this article. No funding was received for this work.

Surgical Removal of Cervical Extradural Cysts Using the Biportal Endoscopic Approach

Symptomatic intraspinal extradural cysts of the cervical spine are uncommon; however, they are usually treated using conventional posterior decompression. Biportal endoscopic surgery is widely used to treat degenerative cervical pathological conditions. This study presented an optimized surgical technique for a biportal endoscopic posterior approach for removal of cervical intraspinal extradural cysts that caused cervical radiculomyelopathy. A broad laminotomy was performed, which was wider than the outer contour of the cysts. The ligamentum flavum was detached from the bony margin and removed after an epidural dissection, and a dense adhesive tissue entrapped the extradural cysts. A spinal endoscope was placed close to the dissection plane and offered a high-resolution magnified view. The cyst capsule was safely dissected from the dura and removed en bloc without dural injury. Postoperatively, neurological deficits, including cervical myelopathy, radiating arm pain, and upper back pain improved in both patients. We successfully removed an extradural cervical cystic mass lesion by using a biportal endoscopic posterior cervical approach without complications. The biportal endoscopic approach may have advantages, such as minimizing trauma to the normal structures of the posterior cervical region, magnified endoscopic view, and early recovery after the surgery. Biportal endoscopy may be used as an alternative surgical treatment for symptomatic cervical intraspinal extradural cystic lesions.