Surgical Planning Research Articles

Is inferior oblique botulinum toxin injection an effective surgical simulator prior to inferior oblique myectomy? A 30-year retrospective review

ABSTRACT Purpose: Botulinum toxin A (BTX) injected into the inferior oblique muscle temporarily simulates the post-operative effect of an inferior oblique myectomy (IOM). This can aid in surgical planning, especially given the irreversible nature of IOM. This study evaluates the efficacy of BTX as a pre-operative simulator and compares its effects to those of IOM. To our knowledge, this is the largest reported series of patients undergoing pre-operative BTX simulations, prior to IOM. Methods: A retrospective review was conducted on all patients receiving inferior oblique BTX between 1 January 1994 and 1 January 2024, by a single surgeon using an electromyography-guided technique. Data, including diagnosis, procedure, and orthoptic measurements, were obtained from electronic and archived paper records. Successful outcome was defined as subjective improvement in symptoms, or objectively as, reduction of vertical angle deviation in primary position by at least 50%, or post-procedure vertical deviation in primary position of ≤5 Prism Dioptres (PD). Results: Sixty-eight patients underwent inferior oblique BTX within the study period. Of these, 48/68 patients (71%) had an improvement in subjective symptoms. Subsequently, 36/48 patients (78%) underwent IOM, 4/48 (8%) patients are awaiting IOM, 4/48 (8%) patients requested repeat BTX despite IOM being offered, and 4/48 (8%) patients had complete resolution with no further intervention. Following IOM, 34/36 (94%) achieved the defined successful outcome, with no significant difference between vertical deviation measurements following BTX or IOM (p < .05). No post-operative diplopia or other complications were identified, and 3/36 (8%) patients demonstrated an asymptomatic over-correction. BTX was deemed unsuccessful in 20 patients (29%). Within this cohort, 12 had no improvement (despite repeat treatment with a higher dose), 3 patients were lost to follow-up, 1 patient died and 4 patients developed problematic diplopia in the primary position, which resolved when the BTX wore off. Conclusions: Inferior oblique BTX is a useful and reliable tool for IOM simulation, prior to irreversible surgery. Its temporary effect on vertical deviation in primary position is comparable to IOM, and can also be used as a tool to identify patients at risk of diplopia, or failure of treatment.

A proof-of-concept study for precise mapping of pigmented basal cell carcinoma in asian skin using multispectral optoacoustic tomography imaging with level set segmentation.

Basal Cell Carcinoma (BCC), the most common subtype of non-melanoma skin cancers (NMSC), is prevalent worldwide and poses significant challenges due to their increasing incidence and complex treatment considerations. Existing clinical approaches, such as Mohs micrographic surgery, are time-consuming and labour-intensive, requiring meticulous layer-by-layer excision and examination, which can significantly extend the duration of the procedure. Current optical imaging solutions also lack the necessary spatial resolution, penetration depth, and contrast for effective clinical use. Here, we introduce photoacoustic imaging, also known as optoacoustic imaging, based Multispectral Optoacoustic Tomography (MSOT) as a promising solution for non-invasive, high-resolution imaging in dermatology, which also measures hemodynamic changes. MSOT offers high isotropic resolution (80μm), increased tissue penetration, and contrast-enhanced 3D spatial imaging map. For the first time, we integrated an automated level set image segmentation methodology on optoacoustic images to further enhance the precision in delineating tumor boundaries. Through this proof-of-concept study in 30 subjects, we demonstrate that this segmentation allows for precise measurement of tumor width, depth, and volume, aiding in preoperative tumor mapping and surgical planning. The MSOT measurements, validated against histology, achieved a correlation coefficient of 0.84 and 0.81 for width and depth respectively, ensuring reliable tumor metrics with a low margin of error. Clinicians can use these tumor metrics to optimize treatment efficacy, while preserving healthy tissue and cosmetic outcomes. This advancement has the potential to revolutionize diagnostics and treatment, significantly improving the patient outcomes in managing NMSC.

Insights and trends review: Use of extended reality (xR) in hand surgery.

Digital transformation through extended reality (xR)-comprising virtual, augmented, mixed, and substitutional reality-has become an integral part of the future of clinical and surgical practice. xR technologies facilitate advanced surgical planning, training, therapies and education, reshaping both personal and institutional healthcare. This paper examines the potential changes that xR has introduced into the field of hand surgery, exploring how xR enhances patient-centric care, increases medical service efficiency and revolutionizes surgical training, planning and therapeutic interventions. Key areas such as surgical assistance, telemedicine, therapies and rehabilitation, medical training and education, and improving patient understanding are highlighted. By synthesizing the current literature, this narrative review articulates the theoretical and practical implications of xR, offering insights into its transformative potential and supporting continuous educational advancement in medical practice.

Value of Noncontrast-Enhanced Vessel Wall MRI in Longitudinal Venous System Invasion Before Robot-Assisted Radical Nephrectomy.

Objectives: To explore the value of vessel wall MRI (VW-MRI) in the preoperative assessment of T3 renal-cell carcinoma (RCC) with varying degrees of longitudinal venous system invasion. Materials and Methods: Patients with RCC with pathological T3 stage between January 2016 and December 2023 were included in this retrospective study. All the patients underwent contrast-enhanced CT (CECT), conventional MRI (con-MRI) or VW-MRI. Images were independently and blindly evaluated at 4-week intervals by three readers. The pathological features reported in the pathological report, combined with clinical data, were used as the reference standards. The incremental value was calculated using net reclassification improvement (NRI) and integrated discrimination improvement. Results: Eighty-two T3 RCC patients (median age, 65 years) were enrolled. The accuracy of T staging in CECT (n = 59), con-MRI (n = 49), and VW-MRI (n = 30) was 69.5%, 71.4%, and 93.3%, respectively. VW-MRI had a statistically incremental value for CECT in the preoperative evaluation of T3a-c stages (T3a: NRI = 0.066, p = 0.04. T3b: NRI = 0.085, p = 0.02. T3c: NRI = 0.178, P = 0.02), especially in renal pelvicaliceal invasion (NRI = 0.154, p = 0.04) and vena cava wall invasion (NRI = 0.263, p = 0.01). Besides, statistically significant preoperative incremental effects were obtained in the assessment of T3a-c stages (T3a: NRI = 0.264, p = 0.01. T3b: NRI = 0.373, p = 0.03. T3c: NRI = 0.202, p = 0.045), renal vein invasion (NRI = 0.630, p = 0.03), and vena cava wall invasion (NRI = 0.185, p = 0.02) when added VW-MRI into con-MRI. VW-MRI changed 24% (4/27) of the previous CECT and con-MRI-based surgical plan. Conclusion: VW-MRI added a preoperative value for evaluating T stage of T3 RCC, especially in the evaluation of renal vein invasion and vena cava wall invasion.

Mixed reality for preoperative planning and intraoperative assistance of surgical correction of complex congenital heart defects.

Mixed reality (MixR) is an innovative visualization tool that presents virtual elements in a real-world environment, enabling real-time interaction between the user and the combined digital/physical reality. We aimed to explore the feasibility of MixR in enhancing preoperative planning and intraoperative guidance for the correction of various complex congenital heart defects (CHDs). Patients underwent cardiac computed tomography or cardiac magnetic resonance and segmentation of digital imaging and communications in medicine (DICOM) images was performed. Three-dimensional models were then uploaded into a MixR headset (Microsoft HoloLens 2), displayed as holograms, and used for preoperative navigation of cardiac anatomy and intraoperative assistance of surgical steps. We adopted MixR in 5 different clinical scenarios: minimally-invasive partial anomalous pulmonary venous connection repair of 5 anomalous veins; intra-extracardiac Fontan completion in right atrial isomerism and dextrocardia; arterial switch operation for transposition of the great arteries with abnormal coronary pattern in situs inversus; complete unifocalization of major aortopulmonary collateral arteries; total artificial heart implantation for failing Fontan. Preoperative MixR allowed a comprehensive understanding of complex anatomical relationships and spatial mapping, using immersive 3D navigation. As a result, the surgeon was able to simulate the surgical approach and plan the best surgical strategy. Intraoperatively, MixR provided a real-time virtual map by overlaying holograms onto the patient's anatomy. MixR represents a promising tool for preoperative planning and 3D visualization in complex CHDs, however, its systematic adoption in the intraoperative setting requires further implementation of current hardware technology and software versatility.

Risk factors for mechanical complications in degenerative lumbar scoliosis with concomitant thoracolumbar kyphosis: does the selection of the upper instrumented vertebra matter?

BackgroundDegenerative lumbar scoliosis (DLS) represents a distinct subset of adult spinal deformity, frequently co-occurring with thoracolumbar kyphosis (TLK) in the sagittal plane. TLK is typically viewed as detrimental in degenerative spinal conditions and has been linked to increased pain severity and a higher prevalence of mechanical complications (MC) as previously reported. The present study aimed to identify the risk factors associated with the development of MC in patients with DLS and concomitant TLK.MethodsThis study retrospectively included 65 DLS patients with a TLK > 20°. During follow-up, MC events were recorded, and patients were categorized into MC and non-MC groups. Spinopelvic parameters were assessed pre- and post-surgery. The locations of the kyphotic apex (KA) and the upper instrumented vertebra (UIV) were documented. Clinical and radiographic data were compared between the two groups. A multivariate logistic regression model was employed to analyze the independent risk factors for MC.ResultsTwenty-nine (44.6%) patients developed at least one MC at final follow-up. At baseline, patients in the MC group exhibited lower bone mineral density (P = 0.002), lower distal lumbar lordosis (DLL, P = 0.025), and higher sagittal vertical axis (SVA, P = 0.005). Post-surgery, the KA shifted cranially with an average vertebral displacement of 2.6 ± 1.8. The proportion of UIV located in the postoperative KA area significantly increased (P < 0.001). The MC group had a higher incidence of Roussouly type mismatch (P = 0.023) and UIV located in the KA area (P = 0.003). Multivariate logistic regression analysis revealed that UIV located in the KA area (OR = 3.798, P = 0.043), increased preoperative SVA (OR = 1.017, P = 0.016) and osteoporosis (OR = 6.713, P = 0.007) were independent risk factors for MC.ConclusionsThe presence of UIV in the KA area, preoperative sagittal imbalance, and osteoporosis were identified as significant risk factors for MC in patients with DLS and concomitant TLK. The spinal morphological characteristics of TLK must be taken into account during surgical planning to prevent placing the UIV within the kyphotic region.

Horizontal extraocular muscle insertion locations in children undergoing extraocular muscle surgery.

The location of extraocular muscle (EOM) insertions is clinically relevant in ophthalmologic surgery. The spiral of Tillaux has been a reference for normal EOM insertion since the nineteenth century. Research on EOM insertions is limited and has focused on adult cadaveric eyes. In this study we investigated the location of EOM insertions in children undergoing EOM surgery. Children who underwent EOM surgery for strabismus or anomalous head position at a large tertiary care center were consecutively identified from October 2022 to December 2023. Intraoperative measurements of medial rectus (MR) and lateral rectus (LR) insertions were compared to the spiral of Tillaux and within patient groups using one-sample and independent-samples t tests, respectively. Associations of EOM insertions with age, refraction, and axial length were evaluated with Pearson correlation. In 292 children who underwent EOM surgery, 528 previously unoperated EOM insertions were recorded. Mean insertions were closer to the limbus than expected by the spiral of Tillaux (MR, 5.21 vs 5.5 mm [P < 0.001]; LR, 6.76 vs 6.9 mm [P = 0.001]). Esotropia was associated with closer EOM insertions than exotropia (MR, P = 0.021; LR, P = 0.045). Males had farther MR insertions than females (5.33 vs 5.03 mm [P < 0.001]). Age was weakly associated with farther EOM insertions (MR, r = 0.215, P < 0.001; LR, r = 0.232, P < 0.001). Myopia was very weakly associated with farther MR insertions (r = -0.145, P = 0.024). In children undergoing EOM surgery, MR and LR insertions were closer to the limbus than expected relative to the spiral of Tillaux. This finding may have implications for surgical planning and outcomes.

Classification and prognostic evaluation of ameloblastoma using multiplanar CT imaging: a retrospective analysis

BackgroundAmeloblastoma is the most prevalent odontogenic tumor of the jaw, with a significant recurrence rate. It was conventionally classified radiographically as unilocular or multilocular. As 3D images become more common, there is a need to reassess this classification. This study aimed to conduct a multi-planar assessment of ameloblastoma using CT images, reclassify the lesions based on locularity, and correlate the locularity with imaging characteristics and recurrence.MethodsPanoramic radiographs and CT images of histopathologically confirmed 255 ameloblastoma patients were included. The analysis encompassed imaging features including locularity, expansion, thinning, cortical perforation, and root resorption. Image characteristics associated with recurrence rate were examined, and image features were assessed based on locularity.ResultsOn panoramic radiographs, most ameloblastomas (68.6%) were classified as multilocular, while 31.4% were unilocular. The CT scan demonstrated that 46.3% of the ameloblastomas were pseudo-multilocular, 29.4% were unilocular, and 24.3% were multilocular. Multilocular cases on panoramic radiographs often appeared as pseudo-multilocular on CT. Cortical perforation, root resorption, and size were significantly correlated with CT locularity types (p < 0.05). The recurrence rate was 14.11%, and the risk of recurrence was substantially reduced by mandibulectomy and a larger tumor size. No other variables were significantly related to recurrence.ConclusionAn accurate diagnosis of ameloblastoma and surgical planning to reduce the recurrence rate are contingent upon the use of three-dimensional imaging modalities, such as CT.

Corrigendum: Computational study of transcatheter aortic valve replacement based on patient-specific models—rapid surgical planning for self-expanding valves

Corrigendum: Computational study of transcatheter aortic valve replacement based on patient-specific models—rapid surgical planning for self-expanding valves

The impact of indocyanine green fluorescence angiography (ICG-FA) on anastomotic leak rates and postoperative outcomes in colorectal anastomoses: a systematic review.

Anastomotic leak (AL) is a major complication in colorectal surgery, significantly contributing to perioperative morbidity and mortality. Among strategies to prevent AL, Indocyanine Green Fluorescence Angiography (ICG-FA) has emerged as a promising method for assessing bowel perfusion intraoperatively. This systematic review evaluates the impact of ICG-FA on AL rates and other postoperative outcomes following colorectal anastomoses. A systematic search was conducted in PubMed, PubMed Central, MEDLINE, and Google Scholar, following PRISMA guidelines. Eligible studies included randomized controlled trials (RCTs), prospective cohort studies, and retrospective cohort studies comparing ICG-FA to controls in adult patients undergoing colorectal resections and anastomoses. Data on AL rates, intraoperative characteristics, and postoperative outcomes were extracted. Quality assessment was performed using the Newcastle-Ottawa Scale and the Revised Cochrane Risk-of-Bias Tool. Sixteen studies (12 retrospective, 1 prospective, and 3 RCTs) involving 3231 patients (1562 ICG-FA and 1669 controls) were included. AL rates were significantly lower in the ICG-FA group (5.18%) compared to controls (11.50%) (p < 0.01). ICG-FA influenced surgical plans in 16.31% of cases. Operative time and ileostomy formation rates were comparable between groups. Reoperation, ileus, and wound infection rates showed minimal differences. Mortality rates were low in both groups (ICG-FA: 0.55%, control: 0.51%). ICG-FA significantly reduces AL rates without increasing operative time or postoperative complications. This technique provides a reliable and safe assessment of bowel perfusion, supporting its integration into colorectal surgery protocols. Further high-quality RCTs are needed to confirm these findings and optimise its application.

IMPACT OF 3D-PRINTED MODELS FOR SURGICAL PLANNING IN RENAL CELL CARCINOMA WITH VENOUS TUMOR THROMBUS. A RANDOMISED MULTICENTER CLINICAL TRIAL.

To determine whether surgical planning based on 3D models allows for better surgical outcomes than conventional surgical planning in terms of 1) complications, 2) surgical time, and 3) hospital stay. This multicenter clinical trial (NCT03738488) included 66 patients diagnosed with renal cell carcinoma and venous thrombus extension who underwent nephrectomy with thrombectomy. Patients were randomized 1:1 to: 1) surgical planning with conventional images (control group) and 2) surgical planning with 3D-printed models (experimental group). We compared the surgical outcomes of each group in terms of 1) complications, 2) surgical time and 3) hospital stay. The mean surgical time and the mean hospital stay was similar between the groups, although there were more patients with no ICU stay in the 3D group 17 (52%) than in the image group (OR: 3.32 (1.16-9.48)) . There were more patients without any complications in the 3D group (n=18) (OR: 5,40 (1,16-16,53), and among those with complications, there were more severe in the imaging group (n=16) (OR: 20,46 (2,33-178,20)). Surgical planning with 3D printing in renal cell carcinoma and venous thrombus extension compared to conventional planning showed a lower ratio of postoperative complications that helped decrease the ICU stay.

Outcomes of OCT imaging-based reoperations in strabismus

PurposeReoperations in strabismus are reportedly needed in 20–40% of cases undergoing surgery. The present study investigated the outcomes of reoperations based on preoperative imaging of extraocular muscle insertions, and whether the Anterior Segment Optical Coherence Tomography (ASOCT) was of value.MethodsPatients with strabismus requiring reoperation with/without previous surgical records at the Advanced Eye Centre, PGIMER, Chandigarh were recruited. All patients underwent a thorough clinical examination and imaging of extraocular muscle insertions on the Swept Source Anterior Segment Optical Coherence Tomography. The accuracy of measuring muscle insertions with the ASOCT was compared with intraoperative caliper readings.ResultsForty-seven muscles (28 patients) were imaged on ASOCT with confirmation intraoperatively during re-operation. The mean age of the patients was 21.6 ± 5.6 years. After looking at the imaging findings, the decision of which muscle to operate on changed in eleven patients (39.2%). The accuracy of ASOCT to measure muscle insertion ± 1 mm was seen in 78.7% (38/47 muscles). The ASOCT could give additional information, such as a slipped muscle and stretched scar in three patients.ConclusionsImaging can be beneficial in achieving successful results in strabismus reoperations with high accuracy. It can be pivotal in surgical planning in reoperations (~ 40%).

Use of computed tomography angiography has potential in planning surgical treatment of an extrahepatic portosystemic shunt in dogs.

To evaluate the impact of intrahepatic portal vein branching (IHPB)-grade assessment using preoperative CT angiography (CTA) on the surgical procedure and prognosis prediction for dogs with an extrahepatic portosystemic shunt (EHPSS). This study involved 146 client-owned dogs with EHPSS. The shunt morphology of EHPSS and IHPB grades was determined using CTA. All dogs underwent surgical attenuation of the shunt with intraoperative portal vein pressure (PVP) measurement, followed by a liver biopsy of the left lateral lobe. The preoperative CTA findings were analyzed according to surgical procedures, intraoperative PVP, hepatic histopathology, and postoperative complications. The grade of IHPB did not correlate with baseline PVP while it significantly correlated with PVP during temporary occlusion and the difference in PVP between before and during the temporary occlusion. The grade of IHPB and PVP had significant differences between the dogs with partial ligation compared with those with complete ligation. The portal vein hypoplasia score on histopathology was generally higher in the dogs with low-grade IHPB than in those with high-grade IHPB. The IHPB grade had no significant influence on postoperative complications and prognosis. This study demonstrated that although the grade assessment system of IHPB using preoperative CTA was unable to predict the prognosis of dogs with a single EHPSS, it may be useful for determining surgical procedure selection. Preoperative CTA is suggested to not only be useful for the diagnosis and classification of EHPSS but also for surgical planning of EHPSS in dogs.

THE ROLE OF DYNAMIC CERVICAL MRI IN DETERMINING THE LEVEL OF POSTERIOR DECOMPRESSION IN CERVICAL SPONDYLOTIC MYELOPATHY.

Cervical spondylotic myelopathy (CSM) is a leading cause of spinal cord dysfunction in adults, often progressing silently. Static MRI is the standard imaging tool but may miss compression caused by neck movement. Dynamic MRI, by capturing flexion and extension views, provides a clearer picture of spinal cord compression, aiding surgical planning and improving outcomes. However, its use is limited due to higher costs and specialized requirements, making its clinical value essential to assess. Eighty-two CSM patients undergoing posterior decompression surgery were divided into two groups: static MRI-based planning (n=43) and combined static and dynamic MRI-based planning (n=39). Neurological outcomes were evaluated using modified Japanese Orthopaedic Association (mJOA) and Visual Analog Scale (VAS) scores pre- and postoperatively. Compression levels identified on static and dynamic MRI were compared. Demographic characteristics were similar between groups. Dynamic MRI identified additional compression levels, mainly at C5-C6 and C6-C7, in 18 patients. Patients in the dynamic MRI group showed significantly greater improvements in mJOA scores (mean: 15.8 ± 1.6 vs. 14.5 ± 1.8, p=0.01) and VAS scores (mean: 3.2 ± 1.4 vs. 4.5 ± 1.8, p=0.01) compared to the static MRI group. Dynamic cervical MRI enhances the identification of compression levels overlooked by static MRI, improving surgical precision and postoperative outcomes in CSM patients. Incorporating dynamic MRI into routine preoperative evaluations may be particularly beneficial for complex, multilevel cases.

Geometric Study and Clinical Case Series for Mandible Reconstruction With a Single-Piece Scapular Free Flap.

Virtual surgical planning (VSP) with simple cutting templates could help surgeons preoperatively plan scapula reconstructions in the vertical and horizontal orientations. Virtually, eight defects were created in ten healthy mandibles and reconstructed with the subject-specific scapula vertically and horizontally. In the clinical series, 15 single-piece scapula mandible reconstructions planned with in-house VSP and guided with simple templates were compared with 15 freehand reconstructions. Virtually, the vertical placement outperformed the horizontal placement in dice score (DSC) and Hausdorff-95 for all but one defect. Clinically, the VSP cohort had shorter operative time (386.6 ± 111.6 min vs. 268.9 ± 50.6 min, p = 0.002), fewer tracheostomies (73% vs. 15%, p = 0.002), lower length of hospital stay (16.6 ± 13.5 days vs. 12.2 ± 8.1 days, p = 0.319), and higher complete/partial union to a non-significant degree (78% vs. 100%, p = 0.471). A single-piece scapula free flap is a versatile option for mandibular reconstruction. VSP has time and cost savings potential and quality of life impact that should be further investigated.

3D Technology for Autologous Breast Reconstruction: Increased Aesthetic Outcomes and Quality of Life Using Patient-Specific Templates.

In autologous breast reconstruction accomplishing aesthetically pleasing outcomes represents an integral challenge. 3-dimensional technology may aid in accurate flap shaping and subsequent breast appearance. The aim of this study was to evaluate the applicability of 3-dimensional technology for surgical planning and its influence on outcomes for breast reconstruction. Outcomes of 50 female patients who underwent deep epigastric artery perforator flap breast reconstruction were analyzed. The patient population was divided into 2 study groups (with 3-dimensional technology vs without) including 25 patients each. Based on individual 3-dimensional scans and simulations, patient-specific templates were used intraoperatively within the 3-dimensional group. Quality of life assessment and aesthetic evaluations of breast appearance were statistically evaluated and compared. Various scales of the BREAST-Q showed statistically significantly better values within the 3-dimensional group (p < 0.05). Concerning breast appearance, patients with 3-dimensional technology rated their breast shape and projection statistically significantly higher compared to the control group (p < 0.05). In addition, blinded ratings of external plastic surgeons were statistically significantly higher in shape, symmetry and projection of breasts using 3-dimensional technology (p < 0.05). All patients treated with 3-dimensional assisted breast reconstruction strongly recommended this approach. Using patient-specific templates represents a practical method facilitating personalized flap planning and shaping. Our results demonstrate that 3-dimensional technology significantly enhances outcomes in breast reconstruction concerning aesthetics and postoperative quality of life.

Coexisting sellar Rathke cleft cyst and planum sphenoidale meningioma: illustrative case.

The co-occurrence of Rathke cleft cysts (RCCs) and meningiomas in the sellar and parasellar regions represents an exceedingly rare clinical entity. Achieving maximal resection through a single operative approach while minimizing adverse events is challenging, often necessitating multiple surgical approaches, as suggested by previous reports. The authors report the case of a 49-year-old female with a history of kidney transplant who presented with headaches and was diagnosed with coexisting RCC and meningioma in the sellar and planum sphenoidale regions, respectively. Given the prolonged, refractory nature of her symptoms and based on her treatment preferences, a two-stage surgical approach was planned. This involved an endoscopic transnasal transsphenoidal approach followed by a right craniotomy to achieve maximal tumor resection while minimizing potential complications. No residual disease or tumor remnants were present at the 6-month follow-up. The pituitary gland was preserved, and the patient's preoperative symptoms had fully resolved. The preoperative diagnosis of concurrent skull base tumors is essential for effective management planning and determining the optimal surgical approach. The proximity of these tumors to critical neurovascular structures necessitates meticulous surgical planning to minimize adverse effects while ensuring maximal tumor resection. https://thejns.org/doi/10.3171/CASE24551.

Nanopore-based random genomic sampling for intraoperative molecular diagnosis

BackgroundCentral nervous system tumors are among the most lethal types of cancer. A critical factor for tailored neurosurgical resection strategies depends on specific tumor types. However, it is uncommon to have a preoperative tumor diagnosis, and intraoperative morphology-based diagnosis remains challenging. Despite recent advances in intraoperative methylation classifications of brain tumors, accuracy may be compromised by low tumor purity. Copy number variations (CNVs), which are almost ubiquitous in cancer, offer highly sensitive molecular biomarkers for diagnosis. These quantitative genomic alterations provide insight into dysregulated oncogenic pathways and can reveal potential targets for molecular therapies.MethodsWe develop iSCORED, a one-step random genomic DNA reconstruction method that enables efficient, unbiased quantification of genome-wide CNVs. By concatenating multiple genomic fragments into long reads, the method leverages low-pass sequencing to generate approximately 1–2 million genomic fragments within 1 h. This approach allows for ultrafast high-resolution CNV analysis at a genomic resolution of 50 kb. In addition, concurrent methylation profiling enables brain tumor methylation classification and identifies promoter methylation in amplified oncogenes, providing an integrated diagnostic approach.ResultsIn our retrospective cohort of 26 malignant brain tumors, iSCORED demonstrated 100% concordance in CNV detection, including chromosomal alterations and oncogene amplifications, when compared to clinically validated assays such as Next-Generation Sequencing and Chromosomal Microarray. Furthermore, we validated iSCORED’s real-time applicability in 15 diagnostically challenging primary brain tumors, achieving 100% concordance in detecting aberrant CNV detection, including diagnostic chromosomal gains/losses and oncogene amplifications (10/10). Of these, 14 out of 15 brain tumor methylation classifications aligned with final pathological diagnoses. This streamlined workflow—from tissue arrival to automatic generation of CNV and methylation reports—can be completed within 105 min.ConclusionsThe iSCORED pipeline represents the first method capable of high-resolution CNV detection within the intraoperative timeframe. By combining CNV detection and methylation classification, iSCORED provides a rapid and comprehensive molecular diagnostic tool that can inform rapid clinical decision. The integrated approach not only enhances the accuracy of tumor diagnosis but also optimizes surgical planning and identifies potential molecular therapies, all within the critical intraoperative timeframe.

The Role of the Sagittal Pars Inclination Angle in the Development of a Spondylolysis

Background and Aims: Spondylolysis refers to a stress fracture of the pars interarticularis. We investigated if there is a correlation between a novel measurement, the sagittal pars inclination angle and the incidence of spondylolysis (pars defect) in adolescent and young adult patients. Methods: A retrospective cohort study was conducted at the Royal Orthopaedic Hospital, UK (a tertiary referral orthopaedic centre) over two years identifying 37 Adult patients under the age of 30 years who had a computed tomography (CT) scan of the lumbar spine. In total 255 pars interarticularis, from levels L2 to L5, were analysed in 37 patients (19 male, 18 female). The pars interarticularis were divided into two groups: (1) pars intact ( N = 217) and (2) pars defect ( N = 38). Statistical analysis of each group and vertebral level was performed including load measurements. Results: In the pars intact group ( N = 217), the sagittal mean ± standard deviation (SD) pars inclination angle for the pars intact group was 17.91 ± 5.62°. In the pars defect group ( N = 38), the mean ± SD sagittal pars inclination angle was 35.95 ± 6.42°. A two-tailed P value was less than .0001. There was an increase in the normal sagittal pars angle from L2 to L5. Conclusion: In this study, an increased sagittal pars inclination angle demonstrated a significant association with spondylolysis. Its implications in the management of athletic individuals, surgical planning and indeed a true causative relationship are yet to be evaluated in future studies.

2D and 3D Classification Systems for Adolescent Idiopathic Scoliosis: Clinical Implications and Technological Advances.

Classification systems for Adolescent Idiopathic Scoliosis (AIS) play an important role in guiding both surgical planning and conservative treatments. Traditional 2D classification systems, such as the Lenke, King and Lehnert-Schroth classifications, have been widely used for the clinical diagnosis and treatment of scoliosis. However, with the growing understanding of the three-dimensional nature of scoliosis and advancements in 3D reconstruction technologies, 3D classification systems are gaining increasing attention. This paper reviews the current applications, advantages, and limitations of different 2D and 3D classification systems, focusing on their clinical significance in treatment planning. While 3D classification systems offer clear advantages in capturing the complexity of spinal deformities, their clinical implementation faces challenges such as high costs and technical complexity. Additionally, studies show that computer-assisted technologies, artificial intelligence can significantly improve the accuracy and consistency of classification systems, reducing human errors. The paper also explores the future directions of classification system development, emphasizing the potential of combining 2D and 3D technologies and the impact of these advancements on personalized scoliosis treatment.