Postoperative Imaging Research Articles

Endoscopic endonasal resection of symptomatic Rathke's cleft cysts: outcomes of the strategy to maintain the fenestration open.

The study intends to clarify the optimal endoscopic endonasal surgical strategy for symptomatic Rathke's cleft cysts (RCCs). We retrospectively analyzed patients with RCCs that underwent EEA surgery. The strategy for surgical and reconstruction method selection was presented. Patients were split into groups of fenestration open or closed. Pre- and postoperative symptoms, imaging, ophthalmologic, and endocrinologic exams were reviewed. The incidence of complications and the recurrence rates were determined. The 75 individuals were all received primary operations. The fenestration closed group contained 32 cases, while the fenestration open group contained 43 cases. The median follow-up period was 39 months. The three primary complaints were headache (n = 51, 68.00%), vision impairment (n = 45, 60.00%), and pituitary dysfunction (n = 16, 21.33%). Of the 51 patients with preoperative headaches, 48 (94.12%) reported improvement in their symptoms following surgery. Twenty-three out of 45 patients (51.11%) experienced an improvement in visual impairment. Pituitary dysfunction was found improved in 14 out of 16 individuals (87.50%). There was no discernible difference in the rate of symptom alleviation between both groups. There were three patients (3/75, 4.00%) had cyst reaccumulation. One of them (1/75, 1.33%), which needed reoperation, was healed using pterional approach. In term of complications, cerebral infections occurred in two patients (2/75, 2.67%). Both of them recovered after antibiotic treatment. No postoperative cerebrospinal fluid rhinorrhea occurred. One patient (1/75, 1.33%) in the open group experienced epistaxis. There was no persistent hypopituitarism or diabetes insipidus (DI). Analysis of headache related factors showed that the presence of wax like nodules was related to it. RCC was successfully treated with endoscopic endonasal surgery with few problems when the fenestration was kept as open as feasible. Preoperative identification of T2WI hypointense nodules may be a potential reference factor for surgical indication.

Comparative Analysis on Vestibular Schwannoma Surgery with and without Intraoperative Fluorescein Sodium Enhancement

Background: Vestibular schwannoma (VS), also known as acoustic neuroma, is a benign, well-encapsulated, and slow-growing tumor that originates from Schwann cells, which form the myelin sheath around the vestibulocochlear nerve (VIII cranial nerve). The surgical treatment of this condition presents a challenging task for surgeons, as the tumor’s location and size make it difficult to remove without causing damage to the surrounding structures. In recent years, fluorescein sodium (FS) has been proposed as a tool to enhance surgical outcomes in VS surgery. This essay will provide an analytical comparison of the use of FS in VS surgery, evaluating its benefits and limitations and comparing surgical outcomes with and without FS-assisted surgery. Methods: In a retrospective study conducted at San Filippo Neri Hospital, we examined VS cases that were operated on between January 2017 and December 2023. The patients were divided into two groups: group A, which consisted of patients who underwent surgery without the use of FS until January 2020 (102 cases), and group B, which included patients who underwent surgery with FS after January 2020 (55 cases). All operations were performed using the retrosigmoid approach, and tumor size was classified according to the Koos, et al. classification system. The extent of surgical removal was evaluated using both the intraoperative surgeon’s opinion and postoperative MRI imaging. Preoperatively and postoperatively, facial nerve function and hearing were assessed. In group B, FS was used to assist the surgical procedures, which were performed using a surgical microscope equipped with an integrated fluorescein filter. Postoperative clinical and MRI controls were performed at six months and annually, with no patients lost to follow-up. Results: This study investigated the impact of intraoperative fluorescein exposure on tumor resection and clinical outcomes in patients with VS. The study found a statistically significant difference in the tumor resection rates between patients who received fluorescein intraoperatively (p = 0.037). Further analyses using the Koos classification system revealed a significant effect of fluorescein exposure, particularly in the Koos 3 subgroup (p = 0.001). Notably, no significant differences were observed in hearing loss or facial nerve function between the two groups. A Spearman correlation analysis revealed a positive correlation between tumor size and Koos, age, and size, but no significant correlation was found between facial nerve function tests. Conclusions: FS-assisted surgery for VS may potentially enhance tumor resection, allowing for more comprehensive tumor removal.

Measurement of the Acetabular Cup Orientation After Total Hip Arthroplasty Based on 3-Dimensional Reconstruction From a Single X-Ray Image Using Generative Adversarial Networks

BackgroundThe purpose of this study was to reconstruct 3-dimensional (3D) computed tomography (CT) images from single anteroposterior (AP) postoperative total hip arthroplasty (THA) X-ray images using a deep learning algorithm known as generative adversarial networks (GANs) and to validate the accuracy of cup angle measurement on GAN-generated CT. MethodsWe used 2 GAN-based models, CycleGAN and X2CT-GAN, to generate 3D CT images from X-ray images of 386 patients who underwent primary THAs using a cementless cup. The training dataset consisted of 522 CT images and 2,282 X-ray images. The image quality was validated using the peak signal-to-noise ratio and the structural similarity index measure. The cup anteversion and inclination measurements on the GAN-generated CT images were compared with the actual CT measurements. Statistical analyses of absolute measurement errors were performed using Mann–Whitney U tests and nonlinear regression analyses. ResultsThe study successfully achieved 3D reconstruction from single AP postoperative THA X-ray images using GANs, exhibiting excellent peak signal-to-noise ratio (37.40) and structural similarity index measure (0.74). The median absolute difference in radiographic anteversion was 3.45° and the median absolute difference in radiographic inclination was 3.25°, respectively. Absolute measurement errors tended to be larger in cases with cup malposition than in those with optimal cup orientation. ConclusionsThis study demonstrates the potential of GANs for 3D reconstruction from single AP postoperative THA X-ray images to evaluate cup orientation. Further investigation and refinement of this model are required to improve its performance.

Pediatric Mandibular Fracture Management: Intraoperative Thermoplastic Splint Fabrication and Circummandibular Wires, without Maxillomandibular Fixation

Summary: Management of mandibular fractures often involves the use of maxillomandibular fixation (MMF) to attain immobility of the fractured segments. This can be used as a primary treatment modality or as an adjunct in fracture management. This technique, however, has its drawbacks due to the great burden of care imposed on patients. In the following case, fixation of a pediatric open mandibular body fracture was attained without the use of MMF, and bone union was achieved. Due to age, safety concerns, long-distance travel, and parent’s preference, the routine management of this type of fracture with MMF using piriform aperture drop wires and circummandibular wires was not done. Instead, the fracture was reduced, and an intraoral mandibular impression was taken in the operating room, which was used to create a stone model. A 2-mm acrylic splint was designed and fabricated from the stone model, and two circummandibular wires were placed. The wires were tightened over the acrylic splint to achieve stabilization of the mandibular reduction. At 4 weeks postoperatively, the splint was removed, and the patient was maintained on a soft diet. At 6 weeks, bone union was appreciated clinically by immobility of the mandibular segments, and the patient was advanced to a regular diet. Occlusion was corrected to premorbid state by clinical findings and 6 months postoperative imaging. This technique represents an effective approach in managing pediatric mandibular fractures when MMF cannot be used.

Long-Term Effects of Pulmonary Valve Implantation and Prosthesis Evolution in Patients with Repaired Tetralogy of Fallot.

Pulmonary valve regurgitation is a significant long-term complication in patients with tetralogy of Fallot (TOF). This study aims to investigate the effects of pulmonary valve implantation (PVI) on the anatomy and function of the right ventricle (RV) and the long-term evolution of the implanted prosthesis in the pulmonary position. A single-center retrospective cohort analysis was performed in 56 consecutive patients with TOF who underwent PVI. The study included patients of both sexes, aged ≥ 12 years, and involved assessing clinical and surgical data, pre- and post-operative cardiovascular magnetic resonance imaging, and echocardiogram data more than 1 year after PVI. After PVI, there was a significant decrease in RV end-systolic volume indexed by body surface area (BSA), from 89 mL/BSA to 69 mL/BSA (p < 0.001) and indexed RV end-diastolic volume, from 157 mL/BSA to 116 mL/BSA (p < 0.001). Moreover, there was an increase in corrected RV ejection fraction [ RVEFC = net pulmonary flow (pulmonary forward flow - regurgitant flow) / R V end-diastolic volume ] from 23% to 35% (p < 0.001) and left ventricular ejection fraction from 58% to 60% (p = 0.008). However, a progressive increase in the peak pulmonary valve gradient was observed over time, with 25% of patients experiencing a gradient exceeding 60 mmHg. Smaller prostheses (sizes 19 to 23) were associated with a 4.3-fold higher risk of a gradient > 60 mmHg compared to larger prostheses (sizes 25 to 27; p = 0.029; confidence interval: 1.18 to 17.8). As expected, PVI demonstrated improvements in RV volumes and function. Long-term follow-up and surveillance are crucial for assessing the durability of the prosthesis and detecting potential complications. Proper sizing of prostheses is essential for improved prosthesis longevity.

Preoperative imaging predicts coracoid graft size and restoration of the glenoid track in Latarjet procedures

BackgroundGlenoid bone grafting procedures are often utilized to address glenoid bone loss in patients with recurrent shoulder instability. The purpose of this study was to determine if preoperative advanced imaging can accurately predict coracoid graft size and conversion of off-track to on-track Hill-Sachs lesions in patients undergoing Latarjet procedures. MethodsPatients who underwent Latarjet procedure for shoulder instability at a single institution from 2012-2020 with pre- and postoperative advanced shoulder imaging (computerized tomography (CT) or magnetic resonance imaging (MRI) scans) were retrospectively reviewed. Glenoid diameter, HS interval (HSI), and measurements of the coracoid length, depth, and height were measured on preoperative imaging. Glenoid track (GT), percent glenoid bone loss, predicted restoration of glenoid track, and the difference between HSI and GT (ΔHSI-GT) were calculated. ResultsSeventeen patients with a mean age of 25± 9 years met inclusion criteria. Average glenoid bone loss preoperatively was 24± 7% and average HSI was 27 ± 5mm. The Latarjet procedure reconstructed 116 ± 8% of the native glenoid, and 104 ± 8% of the predicted diameter. Of the 15 patients that had off-track lesions preoperatively, 11 were successfully converted to on-track lesions (73%). The 4 persistent off-track lesions had a significantly higher HSI (32 ± 2 mm vs. 26 ± 4 mm, p=0.002). Preoperative measurements accurately predicted postoperative glenoid track status in 94% of cases. At a mean follow-up of 2 years, there was no significant difference in recurrence rate or rate of revision stabilization procedures between patients with on-track versus persistent off-track humeral lesions. ConclusionPreoperative advanced imaging measurements can accurately predict whether an off-track Hill-Sachs can be converted to on-track after Latarjet procedure, further enhancing shoulder stability.

Real-world study on the characteristics, post-nephrectomy journey, and outcomes of patients with early-stage renal cell carcinoma based on risk groups.

To examine real-world characteristics, journey, and outcomes among patients with locoregional, nonmetastatic renal cell carcinoma (RCC). A retrospective analysis of medical records from the ConcertAI Oncology Dataset was performed on adults in the United States with newly diagnosed nonmetastatic RCC between January 2012-December 2017 who received surgical treatment, and were followed until August 2021. Patients were stratified based on the risk of recurrence after nephrectomy. Recurrence rate and survival outcomes were assessed. The cohort (n = 439) had a median age of 64 years, 66.1% were male, and 76.5% had clear-cell histology. The median follow-up time from nephrectomy was 39.3 months overall, 41.0 months for intermediate-high-risk patients (n = 377; 85.9%) and 24.1 months for high-risk patients (n = 62; 14.1%). For intermediate-high- and high-risk patients, respectively, 68.4% and 56.5% had ≥1 medical oncologist visit after nephrectomy. Of 260 patients with documentation of postoperative imaging assessments, 72% were ordered by medical oncologists, and the median time from initial nephrectomy to the first scan was 110 days (intermediate-high-risk) and 51 days (high-risk). Provider-documented recurrence occurred in 223 (50.8%) patients, of whom 41.7% had ≥1 medical oncologist visit before the recurrence. Three-year disease-free survival (DFS), and overall survival rates were 49.4% and 80.8% (all patients): 27.7% and 64.7% (high-risk); and 52.9% and 83.3% (intermediate-high-risk). Our study reports low DFS after nephrectomy for patients with intermediate-high- and high-risk RCC. Subsequent approval and use of new and newly approved adjuvant therapeutic options could potentially delay or prevent recurrence.

Relative Cortical Atrophy Index as a Strong Predictor of Recurrence After Surgery for Chronic Subdural Hematoma.

Chronic subdural hematoma (CSDH) presents significant management challenges in neurosurgical practice, with recurrence being a notable postoperative consideration. This study aimed to evaluate the Relative Cortical Atrophy (RCA) Index as a predictor of recurrence after CSDH surgery. A retrospective analysis was conducted on 98 patients who underwent surgical evacuation for unilateral CSDH. The RCA Index was calculated using pre- and postoperative cranial imaging, correlating it with patient demographics, hematoma characteristics, and recurrence. Inter-rater reliability among measurements by 4 independent physicians was assessed using the intraclass correlation coefficient (ICC). Correlation and regression analyses were performed to identify the correlation of the RCA Index with other factors and their potential predicting power of CSDH recurrence, respectively. The study population had a mean age of 74.1 (11.9) years, with a 23.5% (23 patients) recurrence rate of CSDH. The ICC analysis showed excellent inter-rater reliability for RCA Index measurements (ICC: 0.998, 95% CI: 0.997-0.998, P < .001). A higher preoperative RCA Index was significantly associated with recurrence (0.215 [0.031] in the recurrent group vs 0.125 [0.034] in the nonrecurrent group, P < .001). The preoperative RCA Index highly correlated with the postoperative RCA Index (Pearson's correlation: 0.918, P < .001), and there was only a small (average: 0.005) but significant increase in the RCA Index of the unaffected hemisphere after surgery (P = .01).The preoperative RCA Index positively correlated with age, preoperative SDH thickness and volume, and recurrence. A RCA Index cutoff value of 0.165 predicted CSDH recurrence with high sensitivity (95.6%) and specificity (93.3%) (area under the curve = 0.97, 95% CI: 0.93-1). The RCA Index is a simple yet robust predictor of CSDH recurrence. Incorporating this measure into the preoperative assessment may enhance surgical planning and postoperative management, potentially reducing recurrence rates.

Emerging role of carbon fiber-reinforced polyetheretherketone instrumentation in spinal oncology: A systematic review

Spinal metastases are increasing in incidence with affected patients experiencing significant pain and disability. Continuous research and innovation in the field of spinal oncology have given rise to an increase in personalized treatment based on tumor characteristics and various patient-specific factors. Carbon fiber-reinforced polyetheretherketone (CFR-PEEK) instrumentation has gained popularity as an alternative to titanium-based implants primarily due to their ability to minimize imaging artifact. A literature search was performed to find articles that examined the use of CFR-PEEK screws in spinal fusion procedures in oncologic patients. Data from each study were compiled to compare complication rates, durability, and effects on postoperative imaging in patients treated with CFR-PEEK instrumentation to those treated with traditional titanium implants. Overall, CFR-PEEK-based products were similar to titanium hardware in terms of durability and complication rates while CFR-PEEK allows for improved postoperative tumor surveillance and radiosurgical planning.

A 3-Ligament Syndesmotic Injury Is at Higher Risk for Malreduction Than a 2-Ligament Injury: A CT-Based Analysis.

Syndesmotic malreduction is common and has been associated to an impaired outcome. Various risk factors for DTFJ malreduction have been postulated. The aims of this study were to assess the DTFJ malreduction rate based on (1) the severity of the syndesmotic injury, (2) the anatomy of the tibial incisura, and (3) the fixation device used in patients treated with suture-button systems. This retrospective, radiographic study included all adult patients who were treated for an acute, unilateral, and unstable syndesmotic injury with a suture-button system and postoperative bilateral CT imaging. Included were isolated syndesmotic injuries and fracture cases. The number of syndesmotic ligaments injured, that is, 2-ligament (AiTFL+IOL) and 3-ligament (AiTFL+IOL+PiTFL), was rated for each patient. The quality of DTFJ reduction, as well as the anatomy of the tibial incisura, was rated based on the postoperative, bilateral CT images and the intraoperative DTFJ reduction was recalculated based on the drilling-tunnel deviation. The possible influence on the DTFJ malreduction rate was assessed. A total of 147 patients were included, and 94 and 53 patients had a 2- and 3-ligament syndesmotic injury, respectively. In addition, 113 patients were treated with a single-button system, 26 with a double suture-button system, and 8 with a hybrid fixation (suture-button + screw). Malreduction was significantly higher in 3-ligament compared with 2-ligament injuries, both intraoperatively (51% vs 27%; P = .003) and postoperatively (28% vs 11%; P = .006). The tibial anatomy had no significant influence on the malreduction rates. No significant differences were seen per the different fixation devices used independent of the number of ligaments injured. This study did not find an influence of the incisura's anatomy on the DTFJ malreduction rate. However, we did find that 3-ligament syndesmotic injuries carried a higher risk of intra- and postoperative malreduction compared with 2-ligament injuries.

A Rare Case of Clear Cell Carcinoma of the Tongue Base: A Case Report

Clear cell carcinoma is a rare variant of salivary gland carcinoma, and its occurrence in the tongue base is even rarer. We present a case of a 55-year-old female patient with clear cell carcinoma of the tongue base. The patient initially presented with a 3-month history of palpable tongue mass, leading to her visit to the otolaryngology outpatient clinic. The patient underwent a complete resection of the tumor under general anesthesia. Postoperative follow-up imaging studies showed no evidence of recurrence.This case report highlights the diagnostic and management challenges associated with clear cell carcinoma of tongue base and demonstrates that a high index of suspicion is required to diagnose clear cell caricnoma, given its rarity and overlapping features with other clear cell neoplasms.

Are routine, daily chest radiographs (CXR) necessary following (VATS and RATS) lobectomies?

BackgroundConsensus guidelines regarding the amount and necessity of post-operative imaging in thoracic surgery are lacking. The efficacy of daily chest radiographs (CXR) following video-assisted (VATS) and robotic-assisted (RATS) thoracoscopic surgery in directing management has not been previously studied. We hypothesize that abnormal clinical findings, rather than abnormal imaging findings, better predict post-operative complications in patients undergoing VATS/RATS lobectomies. MethodsA retrospective review of VATS and RATS lobectomy patients were performed at a tertiary referral center from 1/1/2019–12/31/2021. Demographics, hospital course, and imaging were evaluated. Descriptive statistics, Chi-Square test, Fisher's exact, Wilcoxon rank sum, and multivariable logistic regression were performed. Our outcomes were post-operative complications requiring a procedure and extended length of stay (LOS) (>2 days post-operatively). ResultsOut of 362 VATS/RATS lobectomy patients, 15 patients had post-operative complications requiring a procedure. Almost all patients who required a procedure had abnormal clinical signs and symptoms (14/15; p < 0.001) while 70 % had expected post-operative day (POD) one CXR findings (11/15; p = 0.463). Multivariable logistic regression demonstrated clinical signs and symptoms independently predicted procedural requirement (odds ratio [OR] = 48, 95 % Confidence Interval [CI]:8.5–267) while abnormal POD one imaging did not. For extended LOS, a positive smoking history (OR = 4.4, 95 % CI:1.4–14.1), number of CXRs (OR = 2.4, 95 % CI:1.8–3.2) and thoracostomy tubes (OR = 5.3, 95 % CI:1.0–27.3) were independent predictors while clinical signs and symptoms was not. ConclusionAbnormal clinical findings may guide management more predictably than abnormal CXRs after VATS/RATS. Routine CXR in the post-operative setting may be unnecessary in those without clinical signs or symptoms. Key messageThere are no consensus guidelines regarding the efficacy of routine, post-operative diagnostic studies after major thoracic lobar resections. The presence of abnormal signs or symptoms after minimally invasive lobectomies may better predict those who will require additional procedures better than the presence of abnormal routine, post-operative chest radiographs.

Proposed Radiographic Parameters to Optimize Clinical Outcomes in Trapezio-Metacarpal Prosthesis Placement Using CT Imaging, with 1-Year Follow-Up.

Addressing trapezio-metacarpal (TMC) osteoarthritis often involves considering TMC joint replacement. Utilizing TMC prostheses offers advantages such as preserving the thumb length and more accurately replicating the thumb's range of motion (ROM). TMC prostheses have an intrinsic risk of dislocation and aseptic loosening. Analyzing pre- and postoperative imaging can mitigate complications and improve prosthetic placement, providing insights into both successes and potential challenges, refining overall clinical outcomes. We conducted a prospective analysis of 30 patients with severe TMC arthritis treated with a Touch© (Kerimedical, Geneva, Switzerland) prosthesis in 2021-2023: X-ray and CT protocols were developed to analyze A) the correct prosthesis placement and B) its correlation with clinical outcomes (VAS, Kapandji and QuickDASH scores) by performing Spearman correlation analysis. The average differences in trapezium height and M1-M2 ratio pre- and post-surgery were, respectively, 1.8 mm (SD ± 1.7; p < 0.001) and 0.04 mm (SD ± 0.04; p = 0.017). Pre-to-postoperative M1 axis length increased by an average of 2.98 mm (SD ± 3.84; p = 0.017). Trapezial cup sinking, indicated by the trapezium index, measured 4.6 mm (SD ± 1.2). The metacarpal index averaged at 11.3 mm (SD ± 3.3). The distance between the centers of the trapezium distal surface and the prosthesis cup was 2.23 mm (SD ± 1.4). The Spearman correlation analysis gave the following results: negative correlations were highlighted between postoperative VAS scores and the M1/M2 ratio and residual trapezium height (correlation coefficient: -0.7, p = 0.03 and -0.064, p = 0.03, respectively) at 6 months; a negative correlation was found at the 3-month mark between QuickDASH and the trapezium residual height (correlation coefficient: -0.07, p = 0.01); and a positive correlation was found for the trapezium index at 1 month (correlation coefficient: 0.07, p = 0.03) and 3 months (p = 0.04) using the Kapandji score. Similarly, we found a positive correlation between the distance between the prosthesis and trapezium centers and QuickDASH score at 1 and 3 months (correlation coefficient: 0.066, p = 0.03; correlation coefficient: 0.07, p = 0.05, respectively) and a positive correlation between prosthesis axis and the residual first metacarpal angle with QuickDASH score at 3 months (correlation coefficient: 0.07, p = 0.02). Pre- and postoperative systematic imaging analysis should become a method for predicting complications and guiding recovery in TMC prosthesis: CT imaging could provide us with radiographical landmarks that are intrinsically linked to clinical outcomes. Further research is necessary to fuel a protocol for the correct intraoperative TMC prosthesis implantation.

Hemodynamic analysis of thoracic endovascular aortic repair with left subclavian artery reconstructed by chimney stent.

The purpose of this study was to investigate the hemodynamic consequences of thoracic endovascular aortic repair which reconstructed left subclavian artery by chimney stent (ch-TEVAR). Two patients who underwent thoracic endovascular aortic repair (TEVAR) and left subclavian artery (LSA) reconstruction using chimney stents were selected. Preoperative and postoperative CTA images were collected to reconstruct hemodynamic models for comparing and analyzing blood pressure, blood flow velocity, and wall shear stress in the aortic arch and its major branches. Concurrently, morphological alterations and position of chimney stent were also assessed. After the reconstruction of LSA in ch-TEVAR, no endoleak was seen, but the stent in LSA was compressed. The blood flow velocity of the LSA increased and disordered, the pressure was reduced, and the WSS was increased. Even more, there were a large amount of turbulence found in the LSA of one case, and its LSA was blocked. Chimney stent reduces the occurrence of endoleak due to its excellent deformation ability, but the compressed stent has a greater impact on the hemodynamics of LSA and eventually leads to LSA occlusion; in order to keep the LSA unobstructed, it is necessary to pay attention to the position of the chimney stent and keep it straight and do not fold or twist. Chimney stent has little influence on the aortic arch and the rest of the aortic arch branches.

Force Balance Reconstruction of the Orbicularis Oris in Secondary Unilateral Cleft Lip Deformity.

Secondary unilateral cleft lip deformities are commonly observed in patients with cleft lip and traditional surgical methods can't completely tackle this problem. The purpose of this study was to evaluate the outcomes of a novel surgical technique using force balance reconstruction of the orbicularis oris. 53 patients with secondary unilateral cleft lip deformity were included in this study, in which the orbicularis oris muscle was reconstructed symmetrically to achieve optimal force balance. Photometric 2d indexes were employed to evaluate the outcome of 27 patients, and 3d indexes for the remaining 26 patients. Aesthetic evaluation and parent-patient satisfaction surveys were also recorded. Significant differences were found in the following: (1) LH (the lip height), LW (the lip width), D1(the vertical distance from the white roll to the vermilion bottom at the christa philtra points) and D2(the vertical distance from the christa philtra points to the facial midline) when comparing preoperative and postoperative 2D images; (2) LH, LW, D1 and D2 when comparing preoperative and follow-up 2D images; (3) RMS (root mean of square) when comparing preoperative and postoperative 3D images. Aesthetic evaluation in the follow-up period was a mean of 4.29, while parent-patient satisfaction of the overall appearance was a mean of 4.41. The results suggest this new muscle reconstruction technique can significantly improve the surgical outcome of secondary unilateral cleft lip deformities. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 ."

P.088 Wounded glioma syndrome: neurologic worsening in patients with subtotal resection in high-grade gliomas

Background: For treatment of high-grade gliomas (HGGs), subtotal resection (STR) may be preferred to minimize injury to eloquent areas. We aimed to characterize neurologic deficits developed in STR patients within the first month post-operatively and to establish a potential threshold for a safe volume of residual tumor to avoid neurological worsening. Methods: This is a single institution retrospective chart review, with 146 charts reviewed and 78 patients deemed eligible. Preoperative deficits and postoperative neurological deficits presenting prior to 1 month after surgery were captured. Imaging features such as tumour volume, edema, and other pertinent imaging characteristics were collected from preoperative and postoperative imaging. Results: Most patients that developed a postoperative deficit presented with motor deficits (55.1%), while only 1.3% of patients developed new or worsening tremor after surgery. On average, in patients with a new deficit, 26.5% of tumor was resected, and all patients had more than 19% of residual tumor. Conclusions: Postoperative neurologic deficits may develop after a subtotal resection when an average of 73.5% of tumor remains. The proposed threshold for tumor resection is greater than 26.5% to minimize the potential of neurologic worsening 1 month postoperatively.

P.122 Left temporal aneurysm resection: surgical approach in Pial-Pial collateral formation from the posterior temporal artery secondary to left internal artery occlusion

Background: The formation of pial-pial collateral network aneurysms due to carotid occlusion is a rare neurological phenomenon. This case details a 69-year-old male who developed a pial-pial collateral network aneurysm secondary to left internal carotid artery occlusion, leading to intracranial hemorrhage. Methods: The patient presented with altered consciousness due to left temporal intracerebral hemorrhage, subdural hematoma, and intraventricular hemorrhage. Cerebral angiography revealed an occluded left internal carotid artery, with superficial temporal artery (STA) and superior orbital artery anastomosis, and extensive pial-pial collaterals from the posterior temporal artery. A 4 mm aneurysm arising from this collateral network was identified. Surgical intervention involved a left temporal craniectomy and excision of the aneurysm, prioritizing the preservation of the STA. N.B., Informed patient consent was obtained in this study. Results: Successful aneurysm removal and preservation of collateral pathways were confirmed by postoperative imaging. The patient exhibited rapid neurological improvement; by postoperative day (POD) one, the patient showed limited response to stimuli. He was extubated by POD4 and discharged on POD27, where he conversed well, was independently ambulatory, and needed minimal to no assistance in activities of daily living. Conclusions: This case highlights the need for careful preoperative planning and intraoperative precision, especially in preserving vital collateral vascular pathways.

P.108 Rate and clinical utility of early postoperative CT head in adult craniotomy

Background: Postoperative cranial neurosurgical imaging practices are highly variable. We evaluated the rate and utility of early postoperative computed tomography (EPCT, defined as a CT head scan within 24h of surgery) in consecutive adult craniotomies. Methods: We retrospectively reviewed consecutive adult craniotomies at the University of Alberta Hospital over a 45-day period (17/09/2022 to 01/11/2022). Electronic medical records were reviewed to extract data on the rate, timing, and utility of EPCT as well as the rate of neurologic deterioration and repeat surgical intervention. Results: A total of 56 patients (27 female; 55.5 ± 2.1 yrs, range: 19-84 years) were identified. All patients underwent EPCT, including 10/56 (17.9%) on POD0 and 46/56 (82.1%) on POD1. Surgical complications (bleeding, extensive pneumocephalus, edema, ischemia) were identified in 8/56 (14.3%) of the EPCT, of which 6 (10.7%) were reported to have neurologic deterioration and 2 (3.6%) underwent further surgical intervention (hematoma evacuation). Clinical and radiological postoperative changes were highly related (p=5.16e-06), and the rate of EPCT being adverse without neurologic deficit, managed surgically, was 1/56 (1.8%). Conclusions: EPCT is routine practice. Given the low rate (1.8%) of repeat surgical intervention in the absence of neurologic deficit despite abnormal EPCT, omitting EPCT in neurologically intact patients may be warranted.

Photon-counting detector CT - first experiences in the field of musculoskeletal radiology.

The introduction of photon-counting detector CT (PCD-CT) marks a remarkable leap in innovation in CT imaging. The new detector technology allows X-rays to be converted directly into an electrical signal without an intermediate step via a scintillation layer and allows the energy of individual photons to be measured. Initial data show high spatial resolution, complete elimination of electronic noise, and steady availability of spectral image data sets. In particular, the new technology shows promise with respect to the imaging of osseous structures. Recently, PCD-CT was implemented in the clinical routine. The aim of this review was to summarize recent studies and to show our first experiences with photon-counting detector technology in the field of musculoskeletal radiology.We performed a literature search using Medline and included a total of 90 articles and reviews that covered recent experimental and clinical experiences with the new technology.In this review, we focus on (1) spatial resolution and delineation of fine anatomic structures, (2) reduction of radiation dose, (3) electronic noise, (4) techniques for metal artifact reduction, and (5) possibilities of spectral imaging. This article provides insight into our first experiences with photon-counting detector technology and shows results and images from experimental and clinical studies. · This review summarizes recent experimental and clinical studies in the field of photon-counting detector CT and musculoskeletal radiology.. · The potential of photon-counting detector technology in the field of musculoskeletal radiology includes improved spatial resolution, reduction in radiation dose, metal artifact reduction, and spectral imaging.. · PCD-CT enables imaging at lower radiation doses while maintaining or even enhancing spatial resolution, crucial for reducing patient exposure, especially in repeated or prolonged imaging scenarios.. · It offers promising results in reducing metal artifacts commonly encountered in orthopedic or dental implants, enhancing the interpretability of adjacent structures in postoperative and follow-up imaging.. · With its ability to routinely acquire spectral data, PCD-CT scans allow for material classification, such as detecting urate crystals in suspected gout or visualizing bone marrow edema, potentially reducing reliance on MRI in certain cases.. Bette S, Risch F, Becker J et al. Photon-counting detector CT - first experiences in the field of musculoskeletal radiology. Fortschr Röntgenstr 2024; DOI 10.1055/a-2312-6914.

A computational modelling tool for prediction of head reshaping following endoscopic strip craniectomy and helmet therapy for the treatment of scaphocephaly

BackgroundEndoscopic strip craniectomy followed by helmet therapy (ESCH) is a minimally invasive approach for correcting sagittal craniosynostosis. The treatment involves a patient-specific helmet designed to facilitate lateral growth while constraining sagittal expansion. In this study, finite element modelling was used to predict post-treatment head reshaping, improving our comprehension of the necessary helmet therapy duration. MethodSix patients (aged 11 weeks to 9 months) who underwent ESCH at Connecticut Children's Hospital were enrolled in this study. Day-1 post-operative 3D scans were used to create skin, skull, and intracranial volume models. Patient-specific helmet models, incorporating areas for growth, were designed based on post-operative imaging. Brain growth was simulated through thermal expansion, and treatments were modelled according to post-operative Imaging available. Mechanical testing and finite element modelling were combined to determine patient-specific mechanical properties from bone samples collected from surgery.Validation compared simulated end-of-treatment skin surfaces with optical scans in terms of shape matching and cranial index estimation. ResultsComparison between the simulated post-treatment head shape and optical scans showed that on average 97.3 ± 2.1 % of surface data points were within a distance range of −3 to 3 mm. The cranial index was also accurately predicted (r = 0.91). ConclusionsIn conclusion, finite element models effectively predicted the ESCH cranial remodeling outcomes up to 8 months postoperatively. This computational tool offers valuable insights to guide and refine helmet treatment duration. This study also incorporated patient-specific material properties, enhancing the accuracy of the modeling approach.