Assessment of Orbital Volume in Frontofacial Advancements

Orbital and Periorbital Dysmorphology in Untreated Pfeiffer Syndrome

BACKGROUND

Visual impairment secondary to orbital and periorbital dysmorphology is frequent in Pfeiffer syndrome patients. The etiopathogenesis of this aberrancy, however, remains unclear.

METHODS

Untreated Pfeiffer syndrome patients (n = 31) and normal control subjects (n = 43) were compared. Craniometric and volumetric analyses related to the orbital and periorbital anatomy were performed using Materialise (Leuven, Belgium) software.

RESULTS

Overall, orbital cavity volume of Pfeiffer patients is reduced by 28 percent (p < 0.001), compared to normal, starting before 3 months of age (p = 0.004). Globe volume was diminished by 10 percent (p = 0.041) before 3 months of age, yet tended to catch up thereafter. However, the retrobulbar soft-tissue volume remained smaller beyond 1 year of age (17 percent, p = 0.003). Globe volume projection beyond the bony orbit increased in all observed ages (82 percent, p < 0.001). The volumes of sphenoid bone, maxilla, and mandible proportionately were restricted by 24 to 25 percent (p = 0.003 to 0.035) before 3 months of age. The volume of maxilla and mandible gradually approximate normal; however, the sphenoid bone volume in Pfeiffer patients remains less than normal (p = 0.002) into childhood. The anteroposterior length of both the zygoma and the maxilla was reduced by 14 percent (p < 0.001). Anterior positioning of the zygoma is less by 23 percent (p < 0.001) in Pfeiffer patients overall, with anterior positioning of maxilla reduced similarly by 23 percent (p < 0.001).

CONCLUSIONS

Pfeiffer syndrome patients develop decreased retrobulbar soft-tissue and globe volume, along with a restricted orbital cavity volume in infancy. Significant hypoplasia of the sphenoid bone is associated with more severe central facial (maxilla) retrusion, compared to lateral facial structures (zygoma).

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, II.

Orbital Volume and Axial Length Development in Individuals Ages 12 to 60 Years With Congenital Microphthalmia: A Retrospective Cohort Study

OBJECTIVE

To analyze the stimulating effect of axial length development on orbital volume development in patients (ages 12-60 years) with congenital microphthalmia.

METHODS

This retrospective cohort study included 43 patients (86 eyes) with congenital microphthalmia. Three-dimensional images of the orbit were generated from past computed tomography scans, and digital orbital volume and axial length measurements were taken. The patients were divided into four age groups for analyses. Paired t tests and one-way analysis of variance tests were used to compare orbital volume and axial length between the affected and unaffected eyes. Pearson correlation analyses and scatter plots were used to investigate the correlations between age, orbital volume, and axial length in the affected and unaffected eyes. Linear regression analysis was used to determine the association between orbital volume and axial length.

RESULTS

The mean orbital volume in the affected and unaffected eyes was 17.08 ± 2.88 and 20.80 ± 2.55 cm3, respectively. The mean axis length in the affected and the unaffected groups was 12.73 ± 3.54 and 23.84 ± 1.43 mm, respectively. Significant differences were observed among orbital (t = 13.538, P < 0.001) volume and axial length (t = 21.339, P < 0.001) in the affected and the unaffected groups. There were no significant differences in affected orbital volume (F = 0.527, P > 0.05), unaffected orbital volume (F = 1.628, P > 0.05), affected axial length (F = 0.946, P > 0.05), and unaffected axial length (F = 2.217, P > 0.05) among the four age groups. According to the Pearson correlations, there were no significant correlations between age and affected volume, unaffected volume, affected axis, and unaffected axis (r = 0.095, 0.097, 0.084, and 0.022, respectively; all P > 0.05). Orbital volume was moderately correlated with axial length in the affected and unaffected groups (r = 0.470 and 0.410, respectively; both P < 0.01). Linear regression analysis revealed that a 1 mm change in axis length was associated with a 0.38 cm3 and 0.73 cm3 change in orbital volume in the affected and unaffected groups, respectively.

CONCLUSIONS

In individuals ages 12 to 60 years old with congenital microphthalmia, the effect of axis length on the orbital volume growth of the affected eye is only half that of the unaffected eye. The eyeball, orbital tissue, and craniofacial development all play an important role in the growth of orbital volume.

Midface Morphology and Growth in Syndromic Craniosynostosis Patients Following Frontofacial Monobloc Distraction

BACKGROUND

Facial advancement represents the essence of the surgical treatment of syndromic craniosynostosis. Frontofacial monobloc distraction is an effective surgical approach to correct midface retrusion although someone consider it very hazardous procedure. The authors evaluated a group of patients who underwent frontofacial monobloc distraction with the aim to identify the advancement results performed in immature skeletal regarding the midface morphologic characteristics and its effects on growth.

METHODS

Sixteen patients who underwent frontofacial monobloc distraction with pre- and postsurgical computed tomography (CT) scans were evaluated and compared to a control group of 9 nonsyndromic children with CT scans at 1-year intervals during craniofacial growth. Three-dimensional measurements and superimposition of the CT scans were used to evaluate midface morphologic features and longitudinal changes during the craniofacial growth and following the advancement. Presurgical growth was evaluated in 4 patients and postsurgical growth was evaluated in 9 patients.

RESULTS

Syndromic maxillary width and length were reduced and the most obtuse facial angles showed a lack in forward projection of the central portion in these patients. Three-dimensional distances and images superimposition demonstrated the age did not influence the course of abnormal midface growth.

CONCLUSION

The syndromic midface is hypoplastic and the sagittal deficiency is associated to axial facial concavity. The advancement performed in mixed dentition stages allowed the normalization of facial position comparable to nonsyndromic group. However, the procedure was not able to change the abnormal midface architecture and craniofacial growth.

Woakes Syndrome: A Rare Cause of Proptosis due to Sinonasal Polyposis

The authors report 2 consecutive adult male patients, aged 61 and 38 years, who presented with painless unilateral proptosis. Their past medical histories were negative for asthma, allergies, and Graves disease. On examination, the nose bridge of the eldest patient was clearly enlarged. Computed tomography scans of the orbits and paranasal sinuses showed in both patients the same radiologic pattern of hyperdense ethmoidal opacifications and expansion of the inferomedial orbital floor. Histopathological analysis of the ethmoidal cells mucosa obtained during inferomedial decompression revealed benign sinonasal polyposis. These cases demonstrate that asymptomatic sinonasal polyposis can be a rare cause of proptosis.

Retroposition of the Globe After Le Fort III Midfacial Distraction

BACKGROUND

Patients with syndromic craniosynostosis exhibit exorbitism due to supraorbital and midfacial retrusion. This study documented the change in sagittal orbital-globe relationship following Le Fort III midfacial advancement.

METHODS

This retrospective case series comprised patients with syndromic craniosynostosis who underwent midfacial distraction from 1997 to 2016. Changes in sagittal globe position in relation to the orbital rims were measured by pre- and postoperative direct anthropometry, computed tomographic scans, or both methods. Descriptive statistics were calculated; significance was set at P < 0.05.

RESULTS

Anthropometry showed a significant increase from superior orbital rim-to-corneal apex (os-acor) (4.1 ± 4.0 mm, P < 0.001) and from inferior orbital rim-to-corneal apex (oi-acor) (4.5 ± 5.3 mm, P < 0.001). The lateral orbital rim to the corneal apex (ol-acor) dimension did not change significantly. Computed tomography measurements confirmed retropositioned globes relative to the anterior border of the orbital cavity (2.5 ± 6.4 mm, P = 0.036). The 2 analytic methods yielded statistically similar results.

CONCLUSION

The globes move posteriorly a mean of 2.5 to 4.5 mm following Le Fort III midfacial distraction in patients with syndromic craniosynostosis. This finding is useful in attaining euophthalmos when planning and executing this procedure.

Three-dimensional imaging of soft and hard facial tissues in patients with craniofacial syndromes: a systematic review of methodological quality

OBJECTIVES

To systematically review the methodological quality of three-dimensional imaging studies of patients with craniofacial syndromes and to propose recommendations for future research.

METHODS

PubMed, Embase and Cochrane databases as well as Grey literature were electronically searched. Inclusion criteria were patients with genetic syndromes with craniofacial manifestations and three-dimensional imaging of facial soft and/or hard tissues. Exclusion criteria consisted of non-syndromic conditions or conditions owing to environmental causes, injury or trauma, facial soft and hard tissues not included in the image analysis, case reports, reviews, opinion articles. No restrictions were made for patients' ethnicity nor age, publication language or publication date. Study quality was evaluated using the Methodological Index for Non-Randomized Studies (MINORS).

RESULTS

The search yielded 2228 citations of which 116 were assessed in detail and 60 were eventually included in this review. Studies showed a large heterogeneity in study design, sample size and patient age. An increase was observed in the amount of studies with time, and the imaging method most often used was CT. The most studied craniofacial syndromes were Treacher Collins, Crouzon and Apert syndrome. The articles could be divided into three main groups: diagnostic studies (34/60, 57%), evaluation of surgical outcomes (21/60, 35%) and evaluation of imaging techniques (5/60, 8%). For comparative studies, the median MINORS score was 13 (12-15, 25-75th percentile), and for non-comparative studies, the median MINORS score was 8 (7-9, 25-75th percentile).

CONCLUSIONS

The median MINORS scores were only 50 and 54% of the maximum scores and there was a lack of prospective, controlled trials with sufficiently large study groups. To improve the quality of future studies in this domain and given the low incidence of craniofacial syndromes, more prospective multicentre controlled trials should be set up.