Comparison of surgical effect in active and inactive Dysthyroid Optic Neuropathy after Endoscopic Transnasal Medial Orbital Decompression.

PURPOSE: To evaluate and compare the changes in orbital soft tissue volume and visual function after endoscopic transnasal medial orbital decompression in patients with active and inactive dysthyroid optic neuropathy (DON). METHODS: This prospective, cohort study recruited 112 patients (112 eyes) with DON who were divided into an active and inactive DON group (56 eyes each) by clinical activity scores. All patients underwent endoscopic transnasal medial orbital decompression. The pre- and post-operative orbital soft tissue volumes were measured with high-resolution computed tomography (CT) using Mimics software. Visual function, including best-corrected visual acuity (BCVA), visual field (VF), and visual evoked potential (VEP), was recorded before and after surgery. RESULTS: Preoperatively, compared with the inactive DON group, the active DON group had greater extraocular muscle volume (EMV) and EMV/orbital volume (OV) ratio, but worse BCVA, VF, and exophthalmos. Postoperatively, although the EMV slightly increased, with the enlarged medial rectus muscle contributing dramatically, the EMV/OV ratio decreased in patients with DON. Besides, visual function including BCVA, VF, VEP and exophthalmos was also improved in both groups after surgery. There were no significant differences in postoperative OV; EMV; EMV/OV ratio; and the BCVA, VF, and VEP parameters between both groups (all P > 0.05). CONCLUSION: Patients with DON who did not respond well to steroids, regardless of disease activity, may benefit from orbital decompression via the decrease in the proportion of EMV in OV, especially patients with active DON, who showed more improved visual function than patients with inactive DON.

Effect of orbital volume in unilateral orbital fracture on indirect traumatic optic neuropathy.

PURPOSE: This retrospective study aimed to analyze the relationship between the volume of the fractured and the normal orbit in patients with unilateral orbital fractures with and without indirect traumatic optic neuropathy (TON). SUBJECTS: Data of 25 patients with unilateral orbital fractures who underwent computer tomography between January 2016 and December 2020 were investigated. Emergency imaging was performed within 2 hours of arrival at the emergency room. The subjects were categorized into two groups: unilateral orbital fractures with and without TON. METHODS AND MEASURES: The assessment of TON was performed during a comprehensive ophthalmologic examination by an ophthalmologist. The stereographic orbit was reconstructed, and the volume was calculated. Other variables examined included age, sex, and cause of orbital trauma. The variables were compared using paired t-tests. Statistical significance was set at p < 0.05. RESULTS: The orbital volume of the non-fractured orbit was 27.50 ± 2.26 and 27.48 ± 2.64 cm3 in the groups with and without TON, respectively. The average volume of the fractured orbit in the TON group was 27.78 ± 2.56 cm3, and there was no significant volumetric difference between the fractured and non-fractured sides in this group. However, the average volume of the fractured orbit without TON was 28.76 ± 3.18 cm3, larger than that of the non-fractured orbit (p = 0.016). CONCLUSIONS: Non-expansion of the fractured orbit was a risk factor for indirect TON in patients with unilateral orbital fractures. Volumetric analysis from primary imaging would expedite the diagnosis and treatment of TON, resulting in optimal outcomes.

3D printing for orbital volume anatomical measurement.

PURPOSE: The aim was to develop a method for reproducible orbital volume (OV) measurement in vivo based on 3D printing. METHODS: Twelve orbits were obtained from dry skulls of the Human Anatomy Department of Lille University. Computer tomography (CT) slice images of these orbits were transformed into stereo-lithography (STL) format and 3D-printed. Bone openings were closed using either putty and cellophane after printing (3D-Orb-1) or at the printing stage in silico using MeshMixer (3D-Orb-2). The results were compared with those of the conventional water-filling method as a control group (Anat-Orb). RESULTS: The observers reported a mean orbital volume of 21.3 ± 2.1 cm3 for the open-skull method, 21.2 ± 2.4 cm3 for the non-sealed 3D-printing method, and 22.2 ± 2.0 cm3 for the closed-print method. Furthermore, the intraclass correlation coefficients (ICCs) showed excellent intra-rater agreement, i.e., an ICC of 0.994 for the first observer and 0.998 for the second, and excellent interobserver agreement (ICC: 0.969). The control and 3D-Orb-1 groups show excellent agreement (ICC: 0.972). The 3D-Orb-2 exhibits moderate agreement (ICC: 0.855) with the control and appears to overestimate orbital volume slightly. CONCLUSION: Our 3D-printing method provides a standardized and reproducible method for the measurement of orbital volume.

Orbital volume, ophthalmic sequelae and severity in unilateral coronal synostosis.

PURPOSE: Unilateral coronal synostosis (UCS) results in an asymmetrical skull, including shallow and asymmetrical orbits, associated with reduced orbital volume and high prevalences of ophthalmic sequelae. Aim is to link orbital volumes in patients with UCS to severity according to UCSQ (Utrecht Cranial Shape Quantifier) and presence of ophthalmic sequelae. METHODS: We included preoperative patients with UCS (≤ 18 months). Orbital volume was measured on CT scans by manual segmentation (Mimics software (Materialise, Leuven, Belgium)), and severity of UCS was determined by UCSQ. Orbital volume of affected side was compared to unaffected side using Wilcoxon signed rank test. Orbital volume ratio was calculated (affected/unaffected volume) and compared to the category of UCSQ by Kruskal-Wallis test. Opthalmic sequelae were noted. RESULTS: We included 19 patients (mean age 7 months). Orbital volume on affected side was significantly lower (p = 0.001), mean orbital volume ratio was 0.93 (SD 0.03). No significant differences in group means of orbital volume ratio between different levels of severity of UCSQ were found (Kruskal-Wallis H (2) = 0.873; p > 0.05). Ophthalmic sequelae were found in 3 patients; one had adduction impairment and strabismus (mild UCS), one had astigmatism (moderate UCS), and one had abduction impairment (on both ipsi- and contralateral side) and vertical strabismus (severe UCS). CONCLUSION: No association between orbital volume ratio and severity of UCS was found. Side-to-side asymmetry in orbital volume was noted. No association between either preoperative orbital volume ratio or severity of UCS and the presence of preoperative ophthalmic sequelae was found.

Post-traumatic enophthalmos secondary to orbital fat atrophy: a volumetric analysis.

PURPOSE: To investigate via volumetric analysis whether orbital fat atrophy occurs in late post-traumatic enophthalmos. METHODS: An IRB-approved retrospective cohort study identified patients with diagnoses of both orbital fracture and enophthalmos with a CT orbits >3 months after injury. Exclusion criteria were surgical repair, other orbital disease or surgery, adjacent sinus disease, and an abnormal contralateral orbit. Images were analyzed using OsiriX imaging software (v.9.0.2, Pixmeo, Switzerland). Total orbital volume and orbital fat volume for the fractured and normal contralateral orbits were measured via three-dimensional volume rendering assisted region-of-interest computation. Enophthalmos was measured radiographically. Paired samples t-tests were used to compare orbital fat and total orbital volumes between the fractured and normal contralateral orbits. RESULTS: Thirteen patients met the inclusion criteria. The numbers of patients with each fracture pattern were floor (4), medial wall (4), floor/medial wall (3), zygomaticomaxillary complex (floor+lateral wall) (1), zygomaticomaxillary complex+medial (inferior/medial/lateral walls) (1). Mean time from injury to CT scan was 21.8 ± 16.3 months. Comparing the fractured and normal contralateral orbits, there was a statistically significant decrease in orbital fat volume (mean difference 0.9 ml (14.2%), p = .0002) and increase in total orbital volume (mean difference 2.0 ml (7.0%), p = .0001). One ml orbital volume change was responsible for 0.83 mm enophthalmos. CONCLUSIONS: In addition to an increase in total orbital volume, orbital fat loss occurs with late post-traumatic enophthalmos due to unrepaired fractures. This suggests correction of bony change alone may be insufficient in some cases, and the use of custom implants may compensate for fat atrophy.

Association between pre- and intraorbital soft tissue volumes and the risk of orbital blowout fractures using CT-based volumetric measurements.

Orbital blowout fractures result from trauma which breaks the bony orbital wall while sparing the rim. Previous research into fracture mechanism has focused on bony anatomy. This study evaluates the role of preorbital and intraorbital soft tissue volume in fracture risk. A retrospective case-control study was conducted on 51 cases of adults with unilateral orbital blowout fracture, matched to 51 controls who had experienced orbital trauma by comparable mechanisms without sustaining a fracture. Axial Computed Tomography (CT) images with orbital fine cuts were assessed on a 3D post-processing workstation to measure the volume of the pre- and intraorbital soft tissues, then compared between the two groups using Mann-Whitney U analysis. In the case group, there were 40 males (78%), injured by assault (66%), fall (12%), motor vehicle collision (10%), or other cause (12%). The control group included 33 males (65%), injured by assault (55%), fall (22%), motor vehicle (4%), or other cause (20%). There was no significant difference in mechanism rates between case and control groups. Median preorbital volumes were 12.5 cm3 in the case group and14.1 cm3 in controls (p = 0.02). Median intraorbital volumes were 24.4 cm3 in the case group and 25.9 cm3 in controls (p = 0.003). CT volumetric analysis shows that patients who sustained blowout fractures have lower preorbital and intraorbital soft tissue volume than those who did not fracture. This underscores the significant role that soft tissues play in dissipating impact forces, both anterior to the orbital rim and within the orbit itself.

An inherited FGFR2 mutation increased osteogenesis gene expression and result in Crouzon syndrome.

BACKGROUND: FGFR2 encodes a fibroblast growth factor receptor whose mutations are responsible for the Crouzon syndrome, involving craniosynostosis and facial dysostosis with shallow orbits. However, few reports are available quantifying the orbital volume of Crouzon syndrome and there was little direct evidence to show FGFR2 mutation actually influencing orbital morphology. METHODS: Ten Crouzon syndrome patients underwent a standard ophthalmologic assessment. Morphology study was carried out based on 3-dimensional computed tomography scan to calculate orbital volume. Genomic DNA was extracted from peripheral blood leukocytes of the patients and genomic screening of FGFR2. A three-dimensional computer model was used to analyse the structural positioning of the mutation site that was predicted possible impact on functional of FGFR2 protein. Real-time PCR was performed to analyse the expression of bone maker gene. RESULTS: We describe a FGFR2 mutation (p.G338R, c.1012G > C) in a Chinese family with Crouzon syndrome. Computational analysis showed the mutate protein obviously changes in the local spatial structure compared with wild-type FGFR2. The expression of osteocalcin and alkaline phosphatase two osteoblast specific genes significantly increased in orbital bone directly from patient compared to normal individual, which may lead to facial dysostosis. This is compatible with the shallow and round orbits in our Crouzon syndrome patient. CONCLUSIONS: Our study further identified G338R FGFR2 mutation (c1012G > C) lead to inherited Crouzon syndrome. Thus, early intervention, both medically and surgically, as well as disciplined by a multiple interdisciplinary teams are crucial to the management of this disorder.

Quantitative analysis of cranial-orbital changes in infants with anterior synostotic plagiocephaly.

PURPOSE: The effects of premature fusion of one coronal suture cause skull and orbital alterations in term of side-to-side asymmetry. This study aimed to quantify the cranio-orbital complex changes related to the severity of skull base dysmorphology in patients with unicoronal synostosis. METHODS: Twenty-four infants affected by unicoronal synostosis were subdivided in three subgroups according to the severity of skull base deformity and their high-resolution CT images were quantitatively analyzed (groups IIa, IIb, III). Dimensions of cranial fossae, intracranial volume (ICV), ICV synostotic and ICV non synostotic side, whole brain volume (WBV), orbital volumes (OV), ICV/WBV, ICVsynostotic/ICVnon-synostotic, and OVsynostotic/OVnon-synostotic were evaluated. RESULTS: Asymmetry and reduction in the growth of the anterior and middle fossae were found in all groups while asymmetry of the posterior cranial fossa was found only in IIb and III groups. In all groups, ICV, WBV, and ICV/WBV were not significantly different while ICVsynostotic/ICVnon-synostotic and OVsynostotic/OVnon-synostotic resulted significant difference (p < 0.05). ICVsynostotic side resulted reduction only in group III. OV on the synostotic side was not significantly reduced although a trend in progressively reducing volumes was noted according to the severity of the group. CONCLUSION: Skull and orbital changes revealed a side-to-side asymmetry but the effects of the premature synostosis were more severe in group III suggesting an earlier timing of premature unicoronal synostosis in group III with respect to the other groups. The assessment of the skull base deformity might be an indirect parameter of severity of skull orbital changes and it might be useful for surgical planning.

Quantitative analysis of orbital soft tissues on computed tomography to assess the activity of thyroid-associated orbitopathy.

PURPOSE: To evaluate the validity of using quantitative volume and density measurements from orbital computed tomography (CT) images to assess the inflammatory activity of patients with thyroid-associated orbitopathy (TAO). METHODS: Computed tomography (CT) scans were obtained from 80 TAO patients and 40 controls, and 3D image analysis was conducted to measure the volume and density (in HU units) of intraorbital and extraorbital fat, extraocular muscle (EOM), and the lacrimal gland. Volume and density measurements of the orbital tissues were compared among active TAO, inactive TAO, and control subjects by ANCOVA. To determine the predictive value of each parameter for TAO activity, logistic regression was performed. RESULTS: The mean volume of extraorbital and intraorbital fat was significantly higher in patients with TAO than controls (p = 0.0019, p = 0.0004), with no significant difference between active and inactive TAO subjects. The mean total EOM volume and lacrimal gland volume was greater in active TAO patients than other groups (p < 0.0001, p < 0.0001). The mean density of extraorbital fat and the lacrimal gland was significantly different between active TAO, inactive TAO, and control groups (p = 0.0002, and p = 0.0487, respectively). Regression models incorporating total EOM volume, lacrimal gland volume, intraorbital fat volume, and density of extraorbital fat and the lacrimal gland could predict active inflammation in patients with TAO with accuracy of 84.5 %. CONCLUSIONS: The measurements of orbital soft tissue volume and density using CT scans can be used as a reliable and feasible technique to establish active inflammation in patients with TAO.

Bony orbital maldevelopment after enucleation.

One common belief in ophthalmology is that enucleation at an early age will result in bony orbital maldevelopment and facial asymmetry. However, the age range in which enucleation is associated with risk of orbital maldevelopment and the extent of asymmetry remains controversial. In this study, patients who had undergone unilateral enucleation at different ages without orbital implantation were analysed to investigate bony orbital development after enucleation. A total of 87 Chinese adult patients were included. Their bony orbital volume and orbital aditus area were measured using three-dimensional reconstructive models based on patients' computer tomography scans. The ratio of the parameter values of the affected orbit to the unaffected orbit was calculated and described as the orbital symmetry index. The results showed that the bony orbit grew until approximately 18 years old. Enucleation after that age did not affect the orbit, whereas enucleation before that age led to significant orbital maldevelopment. The relative reduction ranged up to 20% in orbital volume and 17% in the orbital aditus area. The extent of orbital maldevelopment was correlated to the age of enucleation. The symmetry index of orbital volume = -0.0003x(2)  + 0.0159x + 0.8112 (x = the age of enucleation). The symmetry index of the orbital aditus area = -0.0002x(2)  + 0.0119x + 0.8504 (x = the age of enucleation). The regression formulae were used to predict the severity of orbital asymmetry after unilateral enucleation, and evaluate the necessity and efficacy of interventions following enucleation.

Periumbilical fat graft: a new resource to replace large volume in the orbit.

GOAL: To describe the technique we use to obtain a fat graft from the periumbilical area to replace volume in our patients requiring total or partial orbital volume restoration or replacement. MATERIALS AND METHODS: Under local anaesthesia a one-piece fat auto-graft is obtained from one of the quadrants of the periumbilical zone through a 10- to 15-mm incision at the umbilicus edge. RESULTS: Excised adipose tissue contains connective tracts, with medium and small vascular vessels with discrete thickened wall and preserved endothelium, with more blood cells, and less dead cells. CONCLUSIONS: Fat grafts are the ideal fillers for patients requiring orbital volume replacement. The periumbilical fat graft technique we describe is simple, safe and fast, the learning slope shallow and the results gratifying in both the replaced volume, and the donor area with an invisible scar. The amount of fat that can be obtained with this technique through a minimal incision can be large enough.

Measuring orbital Volume Using Open Source Software and its Application in Orbitozygomatic Fractures.

Study Design: Technical note. Objective: Changes in orbital volume can lead to esthetic and functional complications of the orbit. In this article, the procedure to calculate the orbital volume using the open source software Aliza 3D DICOM is described. Methods: This article describes the steps to use this novel software. To validate the software, the normal orbital volume was calculated bilaterally on CT scans with normal orbital anatomy. The volumes of unilateral orbitozygomatic fracture cases were compared. Results: This open source software has easy access. The normal orbital volume calculated using this software was 24.4 cc ± 0.72. In the unilateral orbitozygomatic fracture cases, an increased orbital volume was calculated. Conclusions: This easy access, inexpensive, and convenient computer aided software can be used to calculate orbital volume facilitating treatment plan for correction of the orbit volume.

Orbital Development in Children with Retinoblastoma: An Imaging-Based Study.

PURPOSE: To examine whether children treated for Retinoblastoma (Rb) have impaired orbital development. METHODS: A retrospective case series was performed among children with Rb treated at a single medical center from 2004 to 2020. Orbital volumes and measurements were assessed by 3-dimensional image processing software. The main outcome measures were differences in orbital growth between Rb and non-Rb eyes assessed at last follow-up. RESULTS: Among 44 patients included (mean age 16.09 ± 18.01 months), a positive correlation between age and orbital volume was observed only in the uninvolved, healthy eyes (p = .03). In unilateral cases, orbital growth in the horizontal, vertical, and depth planes was smaller on the affected side compared to the healthy eyes (p < .05). Orbits that underwent enucleation showed decreased growth over time compared to those treated conservatively (p = .017). CONCLUSIONS: Orbital growth rate is slower in the orbits of children treated for Rb compared to healthy orbits. Enucleation negatively affects orbital growth.

Determining orbital volumes of sheep, goats and gazelles via computed tomography.

BACKGROUND: Orbital volume refers to the sum of bulbus oculi volume and orbital cavity volume. Scientists use orbital volume as a guide to diagnose, treat and prognose various eye diseases such as thyroid eye disease and enophthalmos. OBJECTIVE: This study aims to examine the orbital volumes of sheep, goats and gazelles to demonstrate homotypic variations and interspecific differences between them. METHODS: Crania of six male tuj sheep, five male hair goats and five male gazelle were used in this study. The crania were scanned using a 64-detector multi-detector computed tomography with a slice thickness of 0.625 mm at 80 kV, 200 MA and 639 mGy. The cross-sectional images were stored in DICOM format and then transferred to MIMICS 20.1 software. Afterwards, models were made by establishing the orbital borders on the cross-sections. Volume values were calculated based on the models. RESULTS AND CONCLUSION: No homotypic variation was found between the right and left volumes within the species (p > 0.05). A statistically significant difference was observed in terms of interspecific right and left orbital volumes between sheep and gazelles (p < 0.05). It was concluded that the orbital parameters of the sheep, goats and gazelles in the same family help reveal their differences in the visual anatomy of these species and provide reference data for clinical diagnosis, treatment and the prognosis follow-up of ocular diseases in animals.

Automated 3-D Computer-Aided Measurement of the Bony Orbit: Evaluation of Correlations among Volume, Depth, and Surface Area.

(1)The study aimed to measure the depth, volume, and surface area of the intact human orbit by applying an automated method of CT segmentation and to evaluate correlations among depth, volume, and surface area. Additionally, the relative increases in volume and surface area in proportion to the diagonal of the orbit were assessed. (2) CT data from 174 patients were analyzed. A ball-shaped mesh consisting of tetrahedral elements was inserted inside orbits until it encountered the bony boundaries. Orbital volume, area depth, and their correlations were measured. For the validation, an ICC was used. (3) The differences between genders were significant (p < 10-7) but there were no differences between sides. When comparing orbit from larger to smaller, a paired sample t-test indicated a significant difference in groups (p < 10-10). A simple linear model (Volume~1 + Gender + Depth + Gender:Depth) revealed that only depth had a significant effect on volume (p < 10-19). The ICCs were 1.0. (4) Orbital volume, depth, and surface area measurements based on an automated CT segmentation algorithm demonstrated high repeatability and reliability. Male orbits were always larger on average by 14%. There were no differences between the sides. The volume and surface area ratio did not differ between genders and was approximately 0.75.

Insights into Orbital Symmetry: A Comprehensive Retrospective Study of 372 Computed Tomography Scans.

Background: The operation planning and production of individualized implants with the help of AI-based software after orbital fractures have become increasingly important in recent years. This retrospective study aimed to investigate the healthy orbitae of 372 patients from CT images in the bone and soft tissue windows using the Disior™ Bonelogic™ CMF Orbital software. (version 2.1.28). Methods: We analyzed the variables orbital volume, length, and area as a function of age and gender and compared bone and soft tissue windows. Results: For all variables, the intraclass correlation showed excellent agreement between the bone and soft tissue windows (p < 0.001). All variables showed higher values when calculated based on bone fenestration with, on average, 1 mL more volume, 0.35 mm more length, and 0.71 cm2 more area (p < 0.001). Across all age groups, men displayed higher values than women with, on average, 8.1 mL larger volume, a 4.78 mm longer orbit, and an 8.5 cm2 larger orbital area (p < 0.001). There was also a non-significant trend in all variables and both sexes toward growth with increasing age. Conclusions: These results mean that, due to the symmetry of the orbits in both the bone and soft tissue windows, the healthy orbit can be mirrored for surgical planning in the event of a fracture.

Matrixmidface Preformed Orbital Implants for Three-Dimensional Reconstruction of Orbital Floor and Medial Wall Fractures: A Prospective Clinical Study.

Study Design: Prospective Interventional study. Objective: To evaluate the efficiency of Matrixmidface preformed Orbital plates for three-dimensional reconstruction of orbital floor and medial wall fractures. Methods: This prospective institutional clinical study was conducted on a group of 14 patients who underwent repair of orbital floor and medial wall fracture defects using Matrixmidface Preformed Orbital plates and open reduction and internal fixation of associated fractures. The following parameters were studied preoperative and postoperative enophthalmos, hypoglobus, orbital volume; correction of diplopia, intraoperative and postoperative complications. Results: All 14 patients were males aged between 19 and 42 years. The most common mode of injury was found to be road traffic accidents (RTAs) followed by self-fall and trauma at workplace. Orbital fractures were associated with other concomitant maxillofacial fractures in 12 patients (85.7%) while 2 patients (14.3%) had pure blowout fractures. Significant improvement of enophthalmos was noted from preoperative period to 1 week, 6 weeks, and 6 months postoperatively (P value .02, .01, and .01, respectively). Out of 11 patients with preoperative hypoglobus, 5 patients (45.45%) had persistent hypoglobus in the immediate postoperative period which reduced to 4 patients (36.36%) at 6 weeks postoperatively (p value .00). The postoperative orbital volume of fractured side ranged from 20.3 cm3 to 26.76 cm3 with a mean of 23.50 cm3 ± 1.74. The mean difference between the volumes of the repaired and uninjured sides was found to be .27 cm3 ± .39 (P value .02) denoting that the reconstruction of the orbit closely approximated that of the uninjured side. Conclusions: The Matrixmidface Preformed Orbital plate provides exceptional reconstruction of the orbital blowout fracture defects and ensures satisfactory results clinically and radiographically. The plate ensures an approximate recreation of topographical anatomy of the orbit and adequately restores the orbital volume. It provides adequate correction of asymmetry, hypoglobus, enophthalmos and attempts to restore eye movements, without causing any significant postoperative complication.

Are Age and Trauma Mechanism Associated with Volume Change in the Fractures of the Bony Orbit?

Blowout fractures are common midfacial fractures in which one or several of the bones of orbital vault break. This is usually caused by a direct trauma to the eye with a blunt object such as a fist. Fracturing of the fragile orbital bones can lead to changes in the orbital volume, which may cause enophthalmos, diplopia, and impaired facial aesthetics. Objectives: The aim of this study is to investigate whether there is an association between volume change of the bony orbit and age, gender, or trauma mechanism. Methods: A retrospective study of patients with unilateral blowout or blow-in fractures treated and examined in Päijät-Häme Central Hospital, Lahti, Finland was conducted. Altogether, 127 patients met the inclusion criteria. Their computed tomographs (CT) were measured with an orbit-specific automated segmentation-based volume measurement tool, and the relative orbital volume change between fractured and intact orbital vault was calculated. Thereafter, a statistical analysis was performed. A p-value less than 0.05 was considered significant. Results: We found that relative increase in orbital volume and age have a statistically significant association (p = 0.022). Trauma mechanism and gender showed no significant role. Conclusions: Patient's age is associated with increased volume change in fractures of the bony orbit.

Contemporary Treatment of Silent Sinus Syndrome: A Case Report and Literature Review.

Silent sinus syndrome is a rare clinical entity affecting the maxillary sinus, characterized by ipsilateral enophthalmos and hypoglobus. Its etiology and pathophysiology are still debated. It is diagnosed by clinical examination and confirmed with computed tomography. It is commonly managed surgically. We present the case of a 34-year-old woman with silent sinus syndrome treated with a patient-specific implant for orbital reconstruction, functional endoscopic sinus surgery approach, intraoperative scan, and surgical navigation, successfully restoring orbital volume and sinus ventilation.

Classical Orbital Floor Post-Traumatic Reconstruction vs. Customized Reconstruction with the Support of "In-House" 3D-Printed Models: A Retrospective Study with an Analysis of Volumetric Measurement.

BACKGROUND: Orbital floor fractures (OFFs) represent an interesting chapter in maxillofacial surgery, and one of the main challenges in orbit reconstruction is shaping and cutting the precise contour of the implants due to its complex anatomy. OBJECTIVE: The aim of the retrospective study was to demonstrate, through pre- and postoperative volumetric measurements of the orbit, how the use of a preformed titanium mesh based on the stereolithographic model produced with 3D printers ("In-House" reconstruction) provides a better reconstruction volumetric compared to the intraoperatively shaped titanium mesh. MATERIALS AND METHODS: The patients with OFF enrolled in this study were divided into two groups according to the inclusion criteria. In Group 1 (G1), patients surgically treated for OFF were divided into two subgroups: G1a, patients undergoing orbital floor reconstruction with an intraoperatively shaped mesh, and G1b, patients undergoing orbital floor reconstruction with a preoperative mesh shaped on a 3D-printed stereolithographic model. Group 2 (G2) consisted of patients treated for other traumatic pathologies (mandible fractures and middle face fractures not involving orbit). Pre- and postoperative orbital volumetric measurements were performed on both G1 and G2. The patients of both groups were subjected to the measurement of orbital volume using Osirix software (Pixmeo SARL, CH-1233 Bernex, Switzerland) on the new CT examination. Both descriptive (using central tendency indices such as mean and range) and regressive (using the Bravais-Pearson index, calculated using the GraphPad program) statistical analyses were performed on the recorded data. RESULTS: From 1 January 2017 to 31 December 2021, of the 176 patients treated for OFF at the "Magna Graecia" University Hospital of Catanzaro 10 fulfilled the study's inclusion criteria: 5 were assigned to G1a and 5 to G1b, with a total of 30 volumetric measurements. In G2, we included 10 patients, with a total of 20 volumetric measurements. From the volumetric measurements and statistical analysis carried out, it emerged that the average of the volumetric differences of the healthy orbits was ±0.6351 cm3, the standard deviation of the volumetric differences was ±0.3383, and the relationship between the treated orbit and the healthy orbit was linear; therefore, the treated orbital volumes tend to approach the healthy ones after surgical treatment. CONCLUSION: This study demonstrates that if the volume is restored within the range of the standardized mean, the diplopia is completely recovered already after surgery or after one month. For orbital volumes that do not fall within this range, functional recovery could occur within 6 months or be lacking. The restoration of the orbital volume using pre-modeled networks on the patient's anatomical model, printed internally in 3D, allows for more accurate reconstructions of the orbital floor in less time, with clinical advantages also in terms of surgical timing.