Bryan R. Costin

The Value of Keratometry and Central Corneal Thickness Measurements in the Clinical Diagnosis of Marfan Syndrome

PURPOSE To explore the utility of keratometry and central corneal thickness (CCT) measurements in diagnosis of Marfan syndrome. DESIGN Retrospective chart review of 211 patients referred for ocular examination to rule out Marfan syndrome. METHODS Patients were categorized into Marfan or control groups using current clinical diagnostic criteria. Patients in whom Marfan syndrome could be neither diagnosed nor ruled out were categorized as inconclusive. Those with other connective tissue diseases were excluded from the study. T tests were performed on keratometry and CCT values, and odds ratios (ORs) were calculated. RESULTS Sixty-two patients were in the Marfan group and 98 patients were in the control group. Mean age of the Marfan group was 22.3 years vs 19.3 years in the control group (P = .23). Marfan patients had significantly lower keratometry and CCT values than controls (40.8 diopters (D) [Marfan] vs 43.3 D [control], P = 4.0 x 10(-19); and 543.5 microm [Marfan] vs 564.2 microm [control], P = 9.1 x 10(-6)). The maximum OR for keratometry (17.6) was calculated at 42 D. In Marfan syndrome patients without ectopia lentis, these values were 41.5 D (P = .00026 vs control) and 542.0 microm (P = .0011 vs control). CONCLUSION There was a highly significant difference in keratometry values between Marfan and control patients, and values less than 42 D could be used as a clinical diagnostic criterion for Marfan syndrome. Significant overlap in CCT values between Marfan and control patients suggests that further investigation is necessary to determine the clinical utility of CCT measurements.

Anatomy and histology of the frontalis muscle.

Purpose: To determine the gross and histologic configurations of the medial and lateral frontalis muscle. Methods: After making a midcoronal incision and bluntly dissecting to the orbital rim, the frontalis muscle was marked and measured. A protractor was used to measure the frontalis–orbicularis angle (FOA) and, when present, the angle of central bifurcation (AOB). Three strips of full-thickness forehead soft tissue measuring 0.5 cm × 8 cm were excised 3, 4.5, and 6 cm above the supraorbital notch and analyzed histologically for the presence of skeletal muscle fibers. Data were analyzed using 2-sample t tests, paired t tests, Pearson correlations, and mixed effect models. A p value of ⩽ 0.05 was considered statistically significant. Results: Sixty-four hemifaces of 32 cadavers (16 males) were dissected. All specimens were Caucasian. The average age was 78.2 years (range, 56–102 years). The average FOA was 88.7° (13.0°), and the average AOB was 90.0° (26.4°). A visible midline bifurcation occurred in 28 of 32 subjects (88%) at an average height of 4.7 cm (range, 2.4–7.2 cm) superior to the supraorbital notch. Continuous skeletal muscle fibers were present within the midline bifurcation histologically in 89%, 75%, and 11% of specimens 3.5, 5.0, and 6.5 cm above the supraorbital notch, respectively. In 46% of individuals, skeletal muscle fibers were continuously present microscopically within the gross bifurcation. Conclusion: While a medial frontalis muscle bifurcation occurs grossly in most senescent Caucasians, muscle fibers exist microscopically within this zone in nearly half of individuals.

Orbital and Intraocular Myofibroblastoma

Abstract A 66-year-old woman presented with a blind, painful, hypertensive, and proptotic left eye. Computed tomographic imaging revealed a well-circumscribed mass involving the left orbit and globe. Metastatic work-up failed to reveal extraorbital lesions and the tumor was removed in toto via an evisceration approach orbitotomy. Histopathology and immunohistochemistry were most consistent with mammary-type myofibroblastoma with fascicles of bland, uniform spindle cells that stained positive for desmin and CD34. We are not aware of previous reports of orbital or ocular myofibroblastoma. This neoplasm has not been shown to recur, undergo malignant transformation, or metastasize. Familiarity with its clinical, histopathologic, and immunohistochemical features may improve diagnostic accuracy and treatment decisions for patients presenting with similar findings.

Safety of onabotulinum toxin a injection to the central upper eyelid and eyebrow regions.

Purpose: To evaluate the safety of onabotulinum toxin A injected into the central upper eyelid and eyebrow regions. Methods: The authors retrospectively reviewed the charts of all patients undergoing onabotulinum toxin A injection to the central upper eyelid and eyebrow between February, 2012, and November, 2012. Age, gender, indication, injection sites, number of central units, total number of units, and occurrence of adverse events were all recorded. Results: A total of 300 procedures on 88 patients were performed, in whom the central upper eyelid and/or central eyebrow was injected with onabotulinum toxin A. There were 68 female and 20 male patients. Average age was 68.7 ± 13.3 years (range, 42–92 years). Indications for central eyelid/eyebrow treatment included blepharospasm (34 patients, 176 procedures), hemifacial spasm (21 patients, 40 procedures), facial nerve disorders (2 patients, 9 procedures), and facial rhytides/eyebrow ptosis (31 patients, 75 procedures). The amount of neurotoxin injected into the central eyelid and eyebrow ranged from 2 to 12.5 units per encounter. Complications included diplopia (4% of total encounters), lagophthalmos (1% of total encounters), blepharoptosis (1% of total encounters), and blurry vision (1% of total encounters). Minor local effects, including bruising, bleeding, pain, and mild swelling, were recorded in 3.3% of total encounters. Conclusions: Placement of onabotulinum toxin A into the central upper eyelid and eyebrow is associated with a low rate of blepharoptosis. Central eyelid and eyebrow neurotoxin injection can be safely added to the regimen when treatment calls for chemodenervation of the central orbicularis oculi.

Nasolacrimal System Aeration on Computed Tomographic Imaging: Sex and Age Variation.

Purpose: To investigate variation in aeration of the nasolacrimal drainage system between age groups and genders, and to report the reliability of repeated aeration grading and nasolacrimal canal measurements on CT. Methods: Retrospective review of CT images from 92 individuals, 60 female and 32 male, was conducted by 3 independent reviewers for the presence of air within the nasolacrimal drainage system. Diameter and area measurements were also obtained at the smallest identifiable portion of the nasolacrimal canal by 2 independent reviewers. Results: When air is present on CT, it is seen more fully throughout the nasolacrimal system in men as compared to women. Age data demonstrate that patients from the third and fourth decade have significantly more aeration than older patients. Diameter and area of the nasolacrimal duct within the canal at its narrowest point revealed no correlation with sex, age, or nasolacrimal system aeration. Inter-reviewer reliability shows strong repeatability of aeration grading and nasolacrimal duct measurements between multiple reviewers. Conclusions: The results suggest CT is reliable and repeatable modality to assess nasolacrimal system aeration and nasolacrimal duct diameter. Decreased aeration of the nasolacrimal system in females and the elderly mirrors epidemiologic trends for those at risk to develop primary acquired nasolacrimal duct obstruction. Variables in nasolacrimal drainage system anatomy, specifically nasolacrimal duct diameter and area, did not vary between sexes or age groups, suggesting aeration may be an overlooked variable in nasolacrimal system function.

Dimensions and anatomic variations of the orbicularis oculi muscle in nonpreserved, fresh-frozen human cadavers.

Purpose: To determine average dimensions of the orbicularis oculi muscle (OOM) from the orbital rim and to investigate polymorphic variations through anatomical dissection of nonpreserved, fresh-frozen human cadavers. Methods: The OOM was exposed using sharp and blunt dissection until its distal borders were identified. A metric ruler was used to measure the superior (S line), inferior (I line), and lateral (L line) dimensions of the OOM from the orbital rim. Data collection included age, gender, and race. Data were analyzed using 2-sample t tests, paired t tests, and mixed effect models. A p-value of ⩽0.05 was considered statistically significant. Results: A total of 40 hemifaces of 20 cadavers were dissected. All specimens were Caucasian. Ten specimens were men. Average age was 73.9 years (56–92 years). The overall S line was 1.4 cm (95% confidence interval [CI], 1.23–1.57), the I line was 1.2 cm (95% CI, 1.00–1.36), and the L line was 2.5 cm (95% CI, 2.27–2.68). Men had significantly larger average T, L, and S line values than women (p = 0.003, 0.005, 0.008, respectively). I lines did not differ significantly between genders (p = 0.28). Conclusions: In senescent Caucasians, the OOM extends approximately 1.4 cm superior, 1.2 cm inferior, and 2.5 cm lateral to the orbital rim. The muscle extends significantly further superiorly and laterally in Caucasian men than in women. Knowledge of the extent of the OOM should improve the understanding and the treatment of conditions affecting this region.

Indocyanine green-guided sentinel lymph node biopsy for periocular tumors.

Purpose: To compare the accuracy of indocyanine green (ICG)–guided sentinel lymph node biopsy to sentinel lymph node biopsy performed with technetium-99m in eyelid and in conjunctival malignancies. Methods: Review of a consecutive series of adult patients undergoing sentinel lymph node biopsy for eyelid and conjunctival malignancies between 2009 and 2013. Only patients undergoing both ICG-guided and technetium-99m–guided sentinel lymph node biopsies were included. Results: Five patients were identified: 3 women and 2 men. Four had conjunctival melanoma and 1 had eyelid melanoma. ICG aided in localization and confirmation of the sentinel nodes identified by technetium-99m, and all sentinel lymph nodes identified by technetium-99m were identified by ICG. All patients who underwent both sentinel lymph node modalities had negative lymph node biopsies for micrometastasis, but metastatic disease eventually developed in 1 patient. No safety concerns were identified with the use of ICG in the ocular adnexal region. Conclusions: For certain periocular malignancies, ICG-guided sentinel lymph node biopsy safely identifies sentinel lymph nodes intraoperatively possibly to a similar extent compared with technetium-99m–guided methods.

Classification of Orbital Tumors

Orbital tumors represent approximately 0.1 % of all body tumors and approximately one-fifth of all orbital diseases. Classification schemes vary and stratify orbital tumors based on demographics, site of origin, anatomic location within the orbit, histopathologic features, clinical course, and imaging findings. Defining orbital neoplasia presents difficulties, as choristomas, hamartomas, and inflammatory lesions can present as space-occupying lesions and behave as benign and even malignant, neoplasms. In general, neoplasms of the orbit may be classified as primary, secondary (infiltration from an adjacent structure), or metastatic (from distant structures). Orbital neoplasia can be divided into histological categories that include benign, benign but locally aggressive, and malignant. In some cases, especially lymphoproliferative lesions, a spectrum from benign to malignant exists.

Frontalis Muscle Asymmetry and Lateral Landmarks.

Purpose: To investigate frontalis muscle asymmetry and characterize its lateral interdigitation with the orbicularis oculi muscle. Methods: After making a mid-coronal incision and bluntly dissecting to the orbital rim, the frontalis muscle was exposed, marked, and photographed. The right and left muscle bellies were analyzed and compared in both pixels and cm2 ratios generated with NIH ImageJ software. A ratio of ≥1.5 was considered significantly asymmetric. The lateral interdigitation of the frontalis and orbicularis oculi muscles was measured from the supraorbital notch with a metric ruler. Data were analyzed using 2-sample t tests, paired t tests, log scales, and nonparametric tests were performed for sensitivity analyses. A p value of ⩽0.05 was considered statistically significant. Results: Fifty-eight hemifaces of 29 Caucasian cadavers were studied for muscle belly asymmetry. Thirty-six hemifaces of 18 Caucasian cadavers (9 males) were dissected for lateral landmarks and average age of these specimens was 73 years (range: 35–91 years). Significant asymmetry in muscle belly area was found in 6/29 (20%) specimens, with the right muscle belly larger in all 6 specimens. On average, the right muscle belly area was 1.23 times that of the left (p = <0.001). The average frontalis-orbicularis interdigitation occurred 3.4 cm lateral to the supraorbital notch. Conclusions: Significant frontalis muscle belly asymmetry exists in 20% of Caucasians cadavers. The right muscle belly was larger on average and in all cases of significant asymmetry. The frontalis muscle interdigitates with the orbicularis oculi on average 3.4 cm lateral to the supraorbital notch.

Regional Variations in Orbicularis Oculi Histology.

Purpose:To investigate and compare the histologic compositions of the pretarsal, preseptal, and orbital orbicularis oculi muscle (OOM) using nonpreserved, fresh-frozen, human cadavers. Methods:The OOM was exposed using sharp and blunt dissection. A metric ruler was used to measure and mark 0.5 cm × 1 cm samples from each portion of the right, superior OOM. Samples were excised, fixed in formalin, and completely embedded in paraffin. Five-micrometer-thick, hematoxylin- and eosin-stained sections were generated for each sample and analyzed by an anatomical pathologist. The relative percentages of the 4 main tissue types (skeletal muscle, fibrous tissue, adipose tissue, and neurovascular tissue) were quantified. Results:Forty-two samples were obtained from 14 Caucasian cadavers. On average, the pretarsal samples were composed of 83.5% skeletal muscle, 0.0% adipose, 5.0% neurovascular, and 11.5% fibrous tissue. Average preseptal OOM was 46.5% skeletal muscle, 12.7% adipose, 9.2% neurovascular, and 31.5% fibrous tissue. The orbital OOM was, on average, 42.7% skeletal muscle, 32.7% adipose tissue, 6.9% neurovascular, and 17.7% fibrous tissue. Conclusions:The OOM represents a histologically heterogeneous structure.