Transcript Not just a spinous process

eP-134
Benign Primary Miliary Osteoma Cutis of the face:
A common incidental CT finding!
Dae Hee Kim MD1
Gregg Franco MD2
Hiroshi Shigehara DDS3
Junich Asaumi DDS3
Peter Hildenbrand MD1
1Department
of Radiology, Lahey Hospital & Medical Center, Burlington, MA, USA
2Commonwealth Radiology Associates, Brockton MA, USA
3Department of Oral and Maxillofacial Radiology, Okayama University Graduate School of
Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
Disclosures:
• The authors have no disclosures.
Background
Osteoma Cutis
• Cutaneous Ossification.
• Primary or secondary formation of ossific foci in the skin.
• First described by Martin Wilekens in 1858.
• Distinguished from calcinosis cutis, which represents the deposition
of amorphous calcium salts within the skin.
• Some consider calcinosis cutis as a precursor to osteoma
cutis.
Background
Osteoma Cutis
• Secondary osteoma cutis has been well described in the literature.
• Caused by similar disease processes as in secondary soft tissue
calcification/calcinosis cutis.
•
•
•
•
•
Iatrogenic.
Traumatic.
Metabolic. (e.g. Albright’s hereditary osteodystrophy.)
Inflammatory. (e.g. acne or dermatomyositis.)
Neoplastic. (e.g. basal cell carcinoma.)
• In contrast, Primary (idiopathic) osteoma cutis has sparsely
appeared in the literature.
Background
Miliary osteoma cutis of the face.
• Most frequently reported subclass of primary osteoma cutis.
• Small ossified nodules in the face and scalp dermal soft tissue.
Clinical images adopted from
Bouraoui et al. (2011, right)
and Myllyla et al. (2011, left)
demonstrated miliary
osteoma cutis of the face.
• Available literature agrees upon their idiopathic etiology as well as
benign and asymptomatic clinical presentation.
• However, there are widely varying reports regarding its epidemiology.
• Incidence/prevalence? Very rare disease? vs. common finding?
• Gender or age predilection?
• Some reported increased incidence in elderly or middle-aged
females.
Purpose
• As radiologists, we routinely encounter incidental, small facial
calcified nodules on CT studies performed for a variety of
indications without underlying cause.
• We present a retrospective review of a large CT dataset combined
with a cadaveric case series to establish that routinely encountered
facial dermal calcification/ossification is “Primary Miliary Osteoma
Cutis”, a common, benign and age-related finding.
Materials and Methods
• Study population
• 1389 consecutive sinus CTs with or without contrast enhancement.
• 8 month study period.
• 74 cases were initially excluded due to incomplete imaging or
excessive dental artifact.
• 599 males and 716 females (45.6% vs. 54.4%).
• Ages from 4 to 90 years.
• No significant mean age difference between males and females
(52 vs. 51 year-old, p=0.259).
Study population by age and sex
180
Number of Patients
160
140
120
100
80
Males
60
Famales
40
20
0
1st
2nd
3rd
4th
5th
6th
Age (Decades)
7th
8th
9th
10th
Materials and Methods
• Study population, continued.
• Among included 1315
sinus CTs, the majority of
studies were performed for
sinusitis or upper
respiratory infection related
issues (1112 cases,
84.6%), while the
remaining were for a
variety of other indications.
Materials and Methods
• Image analysis
• The number of dermal radio-opaque lesions with Hounsfield Unit greater
than 150 were counted and their distribution was recorded for each sinus
CT study.
• Statistical Analysis
• All statistical calculations were performed by MedCalc (MedCalc Software,
Ostend, Belgium) and GraphPad Prism 6 (GraphPad Software Inc., La Jolla,
CA).
Results
• Overall prevalence of facial calcified nodules was 42.1% (553/1315).
• Distribution of calcified nodules
All
Male
Female
None
762
352
413
Frontal
285
126
159
Frontal-Maxillary
195
87
108
Maxillary
60
31
29
Temporal
7
3
4
Mandibular/Buccal
4
4
0
Orbital
2
1
1
Subtotal
1315
599
716
• Frontal skin was the most frequent distribution of facial calcified nodules (480
cases, 86.8%), followed by maxillary skin (255 cases, 46.1%).
• 195 cases (35.3%) demonstrated calcifications in both frontal and
maxillary skin tissue.
• Few cases demonstrated calcifications in temporal (7, 1.3%), mandibular
(4, 0.013%) and orbital skin (2, 0.007%).
Results
• Increased age was strongly associated with the increased odds of having facial
calcified nodules.
• Qualitative analysis: To perform a logistic regression analysis between
the presence of facial calcified nodules and the subject’s age, the study
population was dichotomized into two groups with and without facial
calcifications.
• There was a statistically significant association between increased age and
the likelihood of having facial calcified nodules (Odds ratio=1.0178,
p<0.001).
Results
• How about the severity of facial calcifications?
• We used the number of calcified nodules as a surrogate marker for the
severity of facial calcification.
• Quantitative analysis: A simple regression was performed between the
number of calcified nodules and the subject’s age.
• No significant, quantitative correlation between the age and the number
of calcified nodules (R2=0.005, p=0.0952). In other words, increased age
was not correlated with the severity of facial calcification.
450
A scatter plot and
regression line between
the age and the number of
facial calcified nodules.
400
350
300
250
200
150
y = 0.1313x + 6.7336
R² = 0.005
100
50
0
0
10
20
30
40
50
Age
60
70
80
90
100
Results
• Prevalence by sex.
• 252 males out of 599 (42.1%) and 301 out of 716 females (42.0%) had
facial calcified nodules. There was no statistically significant difference
between male and female prevalence (p=0.9708).
• Either male or female sex did not increase the odds of having calcified
nodules (Odds ratio=1.0213, p=0.8528) by logistic regression.
• No statistically significant difference was observed for the severity of
calcified nodules by sex in each age group (see below graph).
Average # Calcified nodules
16
# of calcified nodules by age
14
12
10
8
6
All
4
Male
2
Female
0
1st
2nd
3rd
4th
5th
6th
Age Decade
7th
8th
9th
10th
Radiology-Pathology Correlation:
Cadaveric case series (Shigehara et al. 1998)
• Facial skin specimen obtained from 33 cadavers revealed calcified nodules in
all obtained specimen.
• 19 males and 14 females (ages from 19 to 85 years) without any
documented secondary etiologies of osteoma cutis or calcinosis cutis.
• The causes of death were heart disease (8), cerebral infarction (4),
pneumonia (4), bronchial asthma (2), liver cancer (2), colon cancer (2) and
others.
• Radiographic examination and pathologic examination with electron
microscopy and elemental microanalysis were performed.
Radiographic examination of cadaveric specimen
revealed multiple calcified nodules in facial soft
tissues. Images were obtained from Drs. Shigehara
and Asaumi.
Radiology-Pathology Correlation:
Cadaveric case series (Shigehara et al. 1998)
• Microscopic examination of these facial calcified nodules demonstrated
calcified cortex with fatty medulla, resembling the haversian system of the
mature bone.
A
(A) Histopathologic specimen of a cadaveric calcified nodule revealed mature bone-like
configuration with calcified cortex (red arrows) and central adipose medulla (yellow
arrow). (B) A magnified view of (A) revealed osteocyte-like cells (blue arrows) in
lamellated cortex. Images obtained from Drs. Shigehara and Asaumi.
B
Radiology-Pathology Correlation:
Cadaveric case series (Shigehara et al. 1998)
• Microanalysis revealed similar elemental composition of cadaveric facial
calcified nodules and bone.
A
B
Elemental composition and peak ratios of cadaveric facial nodule (A) and clavicle (B) are
similar to each other and well correlated with the composition of hydroxyapatite. Images
obtained from Drs. Shigehara and Asaumi.
Déjà vu? – Breast skin calcifications
• In breast imaging, benign skin calcifications are routinely encountered and
considered to be secondary to sebaceous inspissations or low-grade infection.
• These skin calcifications are classically described as “calcified nodule with
central lucency”.
A
B
(A) Commonly encountered benign skin calcification (yellow arrows) at the infra-mammary folds in breast imaging
demonstrated classic appearance of “calcified nodule with central lucency”. (B) Plain radiograph focused at the cheek
of a volunteer with puffed cheek demonstrated very similar radiographic appearance of facial calcified nodules (green
arrows) with benign breast calcification in (A). Adopted from Shigehara et al. (1989).
Déjà vu? – Breast skin calcifications
A
B
• Pathologic similarity between benign breast skin calcification and facial calcified nodule.
(A) Spherical nodule of ossification with empty lacuna in benign breast skin calcification. Adopted
from Kopans et al. (1983).
(B) Peripheral calcified matrix and central adipose component in facial calcified nodule resembles
benign skin calcification in (A). The image was obtained from Drs. Shigehara and Asaumi.
Conclusion
• Our large-scale, retrospective review of 1315 sinus CT examination
demonstrated that facial calcified nodules, observed in routine head and face CT
imaging, are common, benign, age-related finding.
• The prevalence of facial calcified nodules in our study was 42.1%, revealing
these nodules are very common findings.
• The most frequent distribution of these facial calcified nodules are frontal and
maxillary skin (540/553 subjects, 97.6%).
• Increased age was strongly associated with the presence of facial nodules but
not correlated with the severity of finding.
• Neither the presence nor the severity of facial calcified nodules was
associated with the sex of the subjects.
• Cadaveric case series with 33 subjects demonstrated benign, mature bone-like
pathologic and elemental characteristics of these facial calcified nodules, which
appear similar to well-documented benign breast skin calcifications in breast
imaging.
Conclusion
• Based on above findings, we concluded that commonly encountered facial
calcified nodules on routine head and neck CT examinations are, in fact, a
manifestation of primary miliary osteoma cutis, mainly described in
dermatologic and plastic surgery literature and overlooked in the radiologic
literature.
• The discrepancy between previous reports regarding the epidemiology of
miliary osteoma cutis is likely due to its benign and asymptomatic nature. In
other words, most cases may have been overlooked until they are sufficiently
advanced or extensive to require dermatological or surgical
attention/intervention. This may also explain the higher incidence of reported
cases in females who are more attuned to facial cosmesis than males.
References
1. Wilckens, M. Ueber die Verknöcherung und Verkalkung der Haut und die s. g. Hautsteine. (Dieterich, 1858).
2. Fazeli, P., Harvell, J. & Jacobs, M. B. Osteoma cutis (cutaneous ossification). The Western journal of medicine 171, 243245 (1999).
3. Reiter, N., El-Shabrawi, L., Leinweber, B., Berghold, A. & Aberer, E. Calcinosis cutis: part I. Diagnostic pathway. Journal
of the American Academy of Dermatology 65, 1-12; quiz 13-14, doi:10.1016/j.jaad.2010.08.038 (2011).
4. Gfesser, M., Worret, W. I., Hein, R. & Ring, J. Multiple primary osteoma cutis. Archives of dermatology 134, 641-643
(1998).
5. Walsh, J. S. & Fairley, J. A. Calcifying disorders of the skin. Journal of the American Academy of Dermatology 33, 693706; quiz 707-610 (1995).
6. Duarte, I. G. Multiple injuries of osteoma skin in the face: therapeutical least invasive in patients with acne sequela - case
report. Anais brasileiros de dermatologia 85, 695-698 (2010).
7. Jeong, K. H., Lew, B. L. & Sim, W. Y. Osteoma cutis as the presenting feature of albright hereditary osteodystrophy
associated with pseudopseudohypoparathyroidism. Annals of dermatology 21, 154-158, doi:10.5021/ad.2009.21.2.154
(2009).
8. Boschert, M. T. & Puckett, C. L. Osteoma cutis of the hand. Plastic and reconstructive surgery 105, 1017-1018 (2000).
9. O'Donnell, T. F., Jr. & Geller, S. A. Primary osteoma cutis. Archives of dermatology 104, 325-326 (1971).
10.Myllyla, R. M. et al. Multiple miliary osteoma cutis is a distinct disease entity: four case reports and review of the
literature. The British journal of dermatology 164, 544-552, doi:10.1111/j.1365-2133.2010.10121.x (2011).
11.Cottoni, F., Dell' Orbo, C., Quacci, D. & Tedde, G. Primary osteoma cutis. Clinical, morphological, and ultrastructural
study. The American Journal of dermatopathology 15, 77-81 (1993).
12.Bouraoui, S. et al. Miliary osteoma cutis of the face. Journal of dermatological case reports 5, 77-81,
doi:10.3315/jdcr.2011.1082 (2011).
13.Safi, Y. et al. Prevalence of osteoma cutis in the maxillofacial region and classification of its radiographic pattern in cone
beam CT. Dermatology online journal 22 (2016).
14.Boneschi, V., Alessi, E. & Brambilla, L. Multiple miliary osteomas of the face. The American Journal of dermatopathology
15, 268-271 (1993).
15.Bowman, P. H. & Lesher, J. L., Jr. Primary multiple miliary osteoma cutis and exogenous ochronosis. Cutis 68, 103-106
(2001).
16.Shigehara, H., Honda, Y., Kishi, K. & Sugimoto, T. Radiographic and morphologic studies of multiple miliary osteomas of
cadaver skin. Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics 86, 121-125 (1998).
17.Kopans, D. B., Meyer, J. E., Homer, M. J. & Grabbe, J. Dermal deposits mistaken for breast calcifications. Radiology 149,
592-594, doi:10.1148/radiology.149.2.6622710 (1983).