The Origin and Course of the Blood Supply to the Lower Eyelid Orbital Fat: Anatomical Study and Clinical Significance

PURPOSE

The aim of this study is to investigate the origin and course of the orbital fat arterial supply in the lower eyelid using traditional anatomy and three-dimensional computed tomography (CT).

METHODS

Twenty-seven cadaver heads were infused with mercury sulfide contrast media through the ophthalmic artery, maxillary artery, transverse facial artery, and facial artery. CT images were obtained after contrast agent injection, three-dimensional CT scans were reconstructed, and the cadaver heads were dissected.

RESULTS

Forty-five qualified hemifaces showed that the orbital fat arterial supply in the lower eyelid originates primarily from the inferomedial muscular trunk (IMT) of the ophthalmic artery and the orbital branch of the infraorbital artery. The medial branch of the IMT terminated at the medial fat pad (35.6%) or the orbital floor (64.4%). The lateral branch terminated at the inferior oblique (IO) muscle (28.9%) or the central and lateral fat pads (17.8%). In 53.3%, the lateral branch extended to the anterior part of the lateral fat pad and terminated in the orbital wall or the zygomaticoorbital foramina. The orbital branch of the infraorbital artery coursed between the orbital floor and the orbital fat, providing supply to the IO muscle, inferior rectus (IR) muscle, nasolacrimal duct, and orbital fat.

CONCLUSION

This study elucidated the origin and course of the orbital fat arterial supply in the lower eyelid, which may help to avoid reducing the blood supply of the orbital fat pedicles during surgery.

LEVEL OF EVIDENCE IV

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 .

Effect of retrobulbar prostaglandin analog injection on orbital fat in rats

PURPOSE

Periorbital fat atrophy is a known side effect of topical prostaglandin analogs (PA). This side effect may have implications in the treatment of diseases like thyroid orbitopathy. In this in vivo study we aimed to evaluate the effects of retrobulbar injection of three different PAs on orbital fat.

METHODS

Eighteen adult male Wistar-albino rats were divided into three groups of six animals. 0.1 ml of 0.03% bimatoprost, 0.005% latanoprost, or 0.005% travoprost was injected into the right orbits and saline was injected into the left orbits, as controls. Both orbits were exenterated after 3 weeks. Histological cross-sections were analyzed using ImageJ image analysis software. Intraconal adipocyte density was calculated.

RESULTS

There was no significant difference in the adipocyte density between the PA injected orbits and the control side in each of the three groups. When calculations from all three groups were analyzed together, again the difference in the adipocyte density between the PA injected orbits and the control side was not significant.

CONCLUSION

No significant fat atrophy was noted in this rat model three weeks after retrobulbar injection of PAs. To evaluate retrobulbar injection of PA as a potential therapy for orbital diseases with fat proliferation, in vivo studies in different animal models, higher concentrations of PA, or longer follow-up duration are required.

Effects of Androgen Deprivation Therapy on Extraocular Muscles, Retrobulbar Orbital Fat, and the Optic Nerve in Patients with Prostate Cancer

INTRODUCTION

The aim of this study was to evaluate radiologically the effects of long-term luteinizing hormone-releasing hormone (LHRH) agonist therapy on extraocular muscle thickness, retrobulbar orbital fat (ROF), and the optic nerve (ON) in prostate cancer (PCa) patients.

METHODS

The retrospective study included patients with primary or recurrent PCa who received androgen deprivation therapy (ADT) for at least 12 months. Each patient underwent gallium-68 prostate-specific membrane antigen positron emission tomography-computed tomography both before and at the end of the 12-month treatment. Thickness of the ON, lateral rectus muscle, medial rectus muscle, superior rectus muscle, and inferior rectus muscle were measured by using the coronal CT sections in soft tissue window. ROF, ocular protrusion, and ON length were measured in sagittal and coronal planes. Changes in these anatomical structures induced by LHRH analogs were investigated by comparing pre- and post-treatment measurements.

RESULTS

A total of 57 patients were included in the study. Median PSA and TT values ​​of the patients before treatment were 36.5 (range, 19.6-51.2) ng/mL and 614.0 (range, 472.0-743.0) ng/dL, respectively, and these values ​​decreased significantly after the treatment (10.6 [range, 5.2-14.2] ng/mL and 36.5 [range, 19.6-51.2] ng/dL, respectively, p < 0.001 for both). After the treatment, there was a statistically significant decrease in the areas of inferior rectus muscle, superior rectus muscle, lateral rectus muscle, and medial rectus muscle (p < 0.001 for all), while significant increases were observed in ROF (11.9%, p < 0.001) and ON thickness (14.3%, p = 0.004). The amount of ocular protrusion also showed a significant increase of approximately 14% after the treatment (14.0 [range, 12.0-16.0] mm vs. 16.0 [range, 14.0-17.2] mm, p < 0.001).

DISCUSSION/CONCLUSION

Our findings, for the first time in the literature, indicated that ADT causes a decrease in extraocular muscle mass and an increase in ROF with ocular protrusion. It can be asserted that these changes are similar to the changes in skeletal muscle and fat mass in other body parts. Further studies with a higher level of evidence are needed to clinically evaluate the increase in ocular protrusion and ON enlargement, which are likely to be caused by the increase in ROF.

Incisional Blepharoplasty for the Asian Eye

The goal of Asian blepharoplasty is to create a lid crease configuration that resembles the natural-appearing crease found in other Asians. Because the Asian upper eyelid contains more prominent preseptal fat resulting in greater lid fullness, soft tissue work in blepharoplasty of the Asian eye is even more diverse and essential than that of whites in order for there to be the sustainability of the eyelid crease. Hence, Asian blepharoplasty should be performed specifically following the orbital anatomy of Asians. This article details the incisional method of blepharoplasty to create natural-appearing creases for Asians with single eyelids.

Herniation of orbital fat through the inferior orbital fissure and into the infratemporal fossa: a cadaveric case report and review

Orbital fat herniation is primarily in a subconjunctival location. However, herniation through the inferior orbital fissure (IOF) has been scantly reported. Here, we report a cadaveric case of herniation of orbital fat through the inferior orbital fissure and into the infratemporal fossa. The cadaver's orbital anatomy and orbital fat herniation were found during routine dissection. The details of this case are reported. We also discuss anatomical variations of the inferior orbital fissure as well as the related vascular and nervous system structures related to orbital fat herniation. This is a rare case of a cadaver with this anatomical abnormality.

Autoantibody against aldehyde dehydrogenase 2 could be a biomarker to monitor progression of Graves' orbitopathy

PURPOSE

This study surveyed the novel autoantigens expressed in the orbital fat tissue of patients with Graves' orbitopathy (GO) and explored the possibility of the autoantibodies against novel autoantigens as biomarkers for GO.

METHODS

We used immuno-proteomic methods to survey novel autoantigens expressed in the orbit fat tissue of GO patients and confirmed by enzyme-linked immunosorbent assay (ELISA).

RESULTS

One protein spot (aldehyde dehydrogenase 2 (ALDH2)) revealed high reactivity with the GO serum than did the healthy control serum and was further verified by ELISA. We found that the plasma anti-ALDH2 antibody level was increased in GO patients compared to healthy control donors. In addition, anti-ALDH2 antibody level was correlated with GO activity classified by clinical activity score(r = 0.588, p < 0.001, using Pearson's correlation).

CONCLUSIONS

These increased levels of anti-ALDH2 antibody in GO serum suggested that ALDH2 could attribute target autoantigen in GO, and anti-ALDH2 autoantibody might serve as a biomarker for GO and help to predict disease activity.

Surgical effects of various orbital decompression methods in thyroid-associated orbitopathy: computed tomography-based comparative analysis

OBJECTIVES

To evaluate the surgical effects of orbital fat decompression and bony decompression in each orbital wall using computed tomography (CT) in thyroid-associated orbitopathy (TAO).

METHODS

In 27 TAO patients (48 orbits) with exophthalmos who underwent orbital wall decompression combined with fatty decompression, we recorded the resected orbital fat volume intraoperatively and estimated the decompression volume of the orbital wall in the deep lateral, medial and inferior walls using postoperative orbit CT images. Then, the correlation between exophthalmos reduction by Hertel reading and decompression volume in each area was analyzed to validate the surgical predictability, surgical efficiency and contribution level to total exophthalmos reduction.

RESULTS

The decompression volume in orbital fat and the deep lateral wall showed relatively high correlation with exophthalmos reduction (surgical predictability) compared to medial and inferior wall. The surgical efficiency was highest at deep lateral wall (2.704 ± 0.835 mm/cm(3)), followed by medial wall (0.892 ± 0.527 mm/cm(3)), orbital fat (0.638 ± 0.178 mm/cm(3)) and inferior wall (0.405 ± 0.996 mm/cm(3)). The actual contribution level to total exophthalmos reduction was highest in fatty decompression, followed by deep lateral decompression.

CONCLUSION

In TAO patients with exophthalmos, orbital fat and deep lateral orbital wall are more predictable and contributory surgical targets for postsurgical exophthalmos reduction.

The periosteal pulley technique for orbital fat realignment and correction of nasojugal groove in lower lid blepharoplasty

BACKGROUND

Removal of orbital fat in lower lid blepharoplasty has been widely replaced by fat realignment over the orbital rim. However, incomplete correction or recurrence of fat bulging is still common compared to a simple fat removal procedure due to improper transfer and fixation of fat over the orbital rim. The authors present a novel technique of orbital fat transfer under the periosteal strip to secure the fat along the orbital rim and prevent recurrence of fat bulging from reherniation.

METHODS

Of the patients who underwent lower blepharoplasties using the periosteal pulley technique during January 2010 to September 2012, 115 were included in this prospective uncontrolled clinical trial. There were 107 females and eight males. The follow-up period ranged from 6 months to 2 years (average 1 year). The results on the last follow-up were categorised into four grades: excellent, good, fair and poor.

RESULT

Of the 115 patients, 10, 81 and 24 patients achieved excellent, good and fair results, respectively. We have three cases of temporary lower lid retraction or ectropion that developed 1 month after surgery and were resolved within 3-4 months. No revision surgery is needed.

CONCLUSION

We propose the periosteal pulley technique as an alternative way of orbital fat transfer in lower lid blepharoplasty. This technique can provide a secure fixation of fat that not only corrects the nasojugal groove but also prevents further herniation of the remaining fat.

Lower lid blepharoplasty: panel discussion, controversies, and techniques

What is the most frequent displeasing effect you see when performing lower eyelid blepharoplasty? What surgical approach do you most frequently use when performing lower eyelid blepharoplasty? How much skin removal of the lower eyelids? When performing lower lid blepharoplasty, what is your preferred method of managing pseudoherniated fat? If you perform midface lifting during blepharoplasty, what approach do you use?

ANALYSIS

Over the past 5 years, how has your technique or approach evolved or what is the most important thing you have learned in doing blepharoplasty?

Differential involvement of orbital fat and extraocular muscles in graves' ophthalmopathy

Graves' ophthalmopathy (GO) is characterized by swelling of orbital fat and extraocular muscles, but little attention has been given to differential involvement of fat and muscles. Advancements in imaging allow rather accurate measurements of orbital bony cavity volume (OV), fat volume (FV) and muscle volume (MV), and are the topics of this review. Ratios of FV/OV and MV/OV neutralize gender differences. In adult Caucasian controls, mean values ± SD of FV/OV are 0.56 ± 0.11 and of MV/OV are 0.15 ± 0.02. FV increases substantially and MV decreases slightly with advancing age, requiring age-specific reference ranges. In 95 consecutive untreated Caucasian GO patients, both FV and MV were within normal limits in 25%, increased FV but normal MV was present in 5%, normal FV but increased MV was detected in 61%, and both increased FV and MV was evident in 9%. Increased FV was associated with more proptosis and longer GO duration. Increased MV was associated with older age, more severe GO (more proptosis and diplopia, worse eye muscle ductions), higher TBII and current smoking. At the cellular and molecular level differential involvement of fat and muscles might be related to differences between fibroblast phenotypes and cytokine profiles in each compartment, to different orbital T cell subsets during the course of the disease and to peroxisome proliferator activator receptor-γ polymorphisms and modulation of 11β-hydroxysteroid dehydrogenase-1. Enlarged muscles are apparently a rather early phenomenon in GO, whereas increases in fat mass occur relatively late. Why a minor subset of GO patients presents with an increase of only fat remains poorly understood.