An Additional Lrp4 High Bone Mass Mutation Mitigates the Sost-Knockout Phenotype in Mice by Increasing Bone Remodeling.

Pathogenic variants disrupting the binding between sclerostin (encoded by SOST) and its receptor LRP4 have previously been described to cause sclerosteosis, a rare high bone mass disorder. The sclerostin-LRP4 complex inhibits canonical WNT signaling, a key pathway regulating osteoblastic bone formation and a promising therapeutic target for common bone disorders, such as osteoporosis. In the current study, we crossed mice deficient for Sost (Sost-/-) with our p.Arg1170Gln Lrp4 knock-in (Lrp4KI/KI) mouse model to create double mutant Sost-/-;Lrp4KI/KI mice. We compared the phenotype of Sost-/- mice with that of Sost-/-;Lrp4KI/KI mice, to investigate a possible synergistic effect of the disease-causing p.Arg1170Trp variant in Lrp4 on Sost deficiency. Interestingly, presence of Lrp4KI alleles partially mitigated the Sost-/- phenotype. Cellular and dynamic histomorphometry did not reveal mechanistic insights into the observed phenotypic differences. We therefore determined the molecular effect of the Lrp4KI allele by performing bulk RNA sequencing on Lrp4KI/KI primary osteoblasts. Unexpectedly, mostly genes related to bone resorption or remodeling (Acp5, Rankl, Mmp9) were upregulated in Lrp4KI/KI primary osteoblasts. Verification of these markers in Lrp4KI/KI, Sost-/- and Sost-/-;Lrp4KI/KI mice revealed that sclerostin deficiency counteracts this Lrp4KI/KI effect in Sost-/-;Lrp4KI/KI mice. We therefore hypothesize that models with two inactivating Lrp4KI alleles rather activate bone remodeling, with a net gain in bone mass, whereas sclerostin deficiency has more robust anabolic effects on bone formation. Moreover, these effects of sclerostin and Lrp4 are stronger in female mice, contributing to a more severe phenotype than in males and more detectable phenotypic differences among different genotypes.

Patterns of hyperostosis during the ontogenic development of Atlantic spadefish (Broussonet, 1782) in Brazilian coast.

Marine teleost species of commercial interest are often reported with hyperostosis, an osteological condition that results in bone thickening. Various specimens of Atlantic Spadefish Chaetodipterus faber (n = 86) obtained from artisanal fishermen in Rio de Janeiro, Brazil, were radiographed and assessed to detect the occurrence of hyperostosis across four different size classes. Of the examined individuals, 58.62% displayed signs of hyperostosis, which manifested in eight skeletal regions, notably in the supraoccipital crest, cleithrum and supraneural areas. In the vertebral column, hyperostosis was more frequently observed in haemal spines than in neural spines, predominantly between the sixth and eighth caudal vertebrae. The smallest size class (<200 mm total length) showed a low frequency of hyperostosis at 7.89%. This frequency escalated for larger classes, reaching 94.12% in individuals measuring 200-300 mm in total length and was observed in all individuals exceeding 300 mm. Hyperostosis exhibited an ontogenetic development pattern, where both the occurrence frequencies and the sizes of the affected bones expanded in proportion to the fish size. This is the first description of the hyperostosis pattern of development for the species, an important commercial resource.

The Accuracy of Classification Systems in Nonsyndromic Sagittal Craniosynostosis.

Numerous classification systems of nonsyndromic sagittal craniosynostosis (NSC) are applied but none has gained a wide acceptance, since each classification is focused on distinct aspects. The aim of the study was to assess the accuracy of 4 classifications of NSC discussed in the literature by defining the associations among the classifications, individual features (sex, age, cranial index), and objective morphologic criteria (frontal bossing, retrocoronal constriction, sagittal ridge, and occipital bulleting). The study was conducted on anonymized thin-cut CT scans of 133 children with NSC 1 to 12 months old (mean age 5.42 mo). The type of cranial dysmorphology was assessed using 4 classification systems, focusing on skull shape, pattern of sagittal suture closure (Heuzé classification), deformation of skull vault (Sakamoto classification), and a single-dominant feature (David classification). Each patient was also independently investigated for the presence of morphologic criteria. A multivariate analysis was performed to explore the relations among the classifications and assess their accuracy. In the analyzed cohort sphenocephaly (38.3%), CFF type by Heuzé (30.8%), type I by Sakamoto (72.9%), and a central type by David (42.9%) were dominant findings. Regarding the morphologic criteria, frontal bossing was observed the most frequently (91.7%). The age of patients and cranial index differed significantly among the shapes of skull and David classifications ( P <0.001). The shape-based system showed the strongest correlation with other classifications and with measurable variables. Other classifications have much in common and some overlap, but none of them constitutes a standalone system to define all aspects of cranial dysmorphology in NSC.

RESOLUTION OF CALVARIAL HYPEROSTOSIS IN AFRICAN LION CUBS (PANTHERA LEO LEO) AFTER VITAMIN A SUPPLEMENTATION.

Two female (FL 1, FL 2) and one male (ML) 11-wk-old, intact, captive African lion cubs (Panthera leo leo) were presented with a history of mild vestibular signs. Initial serum vitamin A concentrations were low (140 nmol/L) for ML. Calvarial hyperostosis was confirmed using computed tomography (CT) of the head and cervical vertebrae in each cub. CT measurements were adapted in relation to the skull width. ML showed the most pronounced thickening of the tentorium cerebelli and occipital bone, represented by a tentorium cerebelli to skull width ratio (TCR) of 0.08 (FL 1: 0.06, FL 2: 0.05) and a basisphenoid to skull width ratio (BBR) of 0.07 (FL 1: 0.06, FL 2: 0.04). Magnetic resonance imaging (MRI) revealed cerebellar herniation and cervical intramedullary T2-weighted hyperintensity from C1, extending caudally for at least two cervical vertebrae in all cubs. Treatment was initiated with subcutaneous vitamin A supplementation and feeding of whole carcasses. Improvement in ataxia was noticed 3 wk later. Follow-up CT and MRI examinations were performed in ML after 3 and 8 mon. The affected bones appeared slightly less thickened and TCR and BBR had decreased to 0.05 after 3 mon. The cerebellum remained mildly herniated, accompanied by amelioration of cervical T2w hyperintensities. After 8 mon, evaluation and diagnostic imaging revealed further improvement regarding the neurologic status and measurements (TCR 0.05, BBR 0.04) despite persistence of a subtle cerebellar herniation. In conclusion, bone remodeling and improvement in clinical signs may be achievable in young lion cubs presented with calvarial hyperostosis and may be attributable to high-dose vitamin A supplementation.

[Convexity hyperostotic meningioma en plaque: a systematic review]. / Ploskostnye giperostoticheskie meningiomy svoda cherepa. Sistematicheskii obzor literatury.

BACKGROUND: Planar hyperostotic meningiomas account for 2-9% of intracranial meningiomas. They are characterized by planar node following the contours of the inner surface of the skull. Hyperostosis is present in most cases. Timely diagnosis of skull base tumors is usually simple due to early involvement of the cranial nerves. However, convexity meningiomas en plaque usually reach large dimensions that complicates surgery and radiotherapy. OBJECTIVE: To analyze the current state of diagnosis, molecular biology and surgical treatment of hyperostotic meningiomas en plaque. MATERIAL AND METHODS: A systematic review was performed in accordance with the PRISMA guidelines. Searching for literature data included the following keywords: «planar meningioma¼, «hyperostotic meningioma¼, «meningioma en plaque¼, «infiltrative meningioma¼. We reviewed the PubMed and Google Scholar databases until May 2023 and enrolled only full-text Russian-, English- or French-language reports. RESULTS AND DISCUSSION: Among primary 332 reports, 35 references met the inclusion criteria. We found less severity or absence of focal neurological symptoms, comparable incidence of intracranial hypertension and no histological differences between planar and nodular meningiomas. Analysis of molecular biological features of planar meningiomas, including cell cultures, is feasible. There is no consensus regarding surgical treatment and radiotherapy. Most publications are case reports. CONCLUSION: The results of treatment of planar hyperostotic meningiomas, especially large and giant ones, are unsatisfactory. There is no a generally accepted algorithm for treating patients in the literature. This problem requires further research.

Imaging Features of Primary Intraosseous Meningiomas.

OBJECTIVE: To describe the imaging features of primary intraosseous meningiomas (PIMs) to aid an accurate diagnosis. METHODS: Clinical materials and radiological data for 9 patients with pathologically confirmed PIMs were reviewed comprehensively. RESULTS: Most lesions involved inner and outer plates of the calvaria and all were relatively well circumscribed. Upon computed tomography, portions of the solid neoplasm were hyperattenuated or isoattenuated. Hyperostosis was found in many lesions, but calcification was seen rarely. On magnetic resonance imaging, most neoplasms were hypointense on T1-weighted images, hyperintense on T2-weighted images, and heterogeneous on fluid-attenuated inversion recovery images. In most cases, the soft tissue of neoplasms showed hyperintense on diffusion-weighted imaging and hypointense on apparent diffusion coefficient. All lesions were obviously enhanced after gadolinium administration. Each patient accepted surgical treatment and recurrence was not observed during follow-up. CONCLUSIONS: Primary intraosseous meningiomas are very rare tumors that occur usually in later life. They are well-defined and tend to involve the inner and outer plates of the calvaria, with a classic appearance of hyperostosis on computed tomography. Primary intraosseous meningiomas display hypointense on T1-weighted images, hyperintense on T2-weighted images, and hyperattenuated or isoattenuated on computed tomography. Hyperintense on diffusion-weighted imaging, hypointense on apparent diffusion coefficient can also be found. Obvious enhancement supplied additional information for an accurate diagnosis. A neoplasm with these features should raise the suspicion of a PIM.

Neurological manifestations in patients and disease carriers in an Italian family with osteosclerosis.

BACKGROUND: Hereditary cranial hyperostosis is a rare disease never described in Italy, so the neurological manifestations in patients and carriers of the disease have been little studied. METHODS: We describe the neurological and neuroimaging features of patients and carriers of the gene from a large Italian family with sclerosteosis. RESULTS: In this family, genetic testing detected the homozygous p.Gln24X (c.70C > T) mutation of the SOST gene in the proband and a heterozygous mutation in 9 siblings. In homozygous adults, severe craniofacial hyperostosis was manifested by cranial neuropathy in childhood, chronic headache secondary to intracranial hypertension, and an obstructive sleep apnea syndrome in adults. In one of the adult patients, there was a compressible subcutaneous swelling in the occipital region caused by transosseous intracranial-extracranial occipital venous drainage, a compensation mechanism of obstructed venous drainage secondary to cranial hyperostosis. Mild cranial hyperostosis causing frequent headache and snoring was evident in the nine heterozygous subjects. CONCLUSIONS: Multiple cranial neuropathies and headache in children, while severe chronic headache and sleep disturbances in adults, are the neurological manifestations of the first Italian family with osteosclerosis. It is reasonable to extend neurological and neuroimaging evaluation to gene carriers as well.

Skeletal manifestations of disease experience: Length of illness and porous cranial lesion formation in a contemporary juvenile mortality sample.

OBJECTIVES: Porous lesions of the orbit (cribra orbitalia [CO]) and cranial vault (porotic hyperostosis [PH]) are used as skeletal indicators of childhood stress. Because they are understudied in contemporary populations, their relationship to disease experience is poorly understood. This paper examines the relationship between length of childhood illness and CO/PH formation in a clinically documented sample. "Turning points," which identify the window for lesion formation for CO/PH, are defined, implications for hidden heterogeneity in frailty are considered. METHODS: Data are from 333 (199 males; 134 females) pediatric postmortem computed tomography scans. Individuals died in New Mexico (2011-2019) and are 0.5 to 15.99 years (mean = 7.1). Length of illness was estimated using information from autopsy and field reports. Logistic regression was used to estimate predicted probabilities, odds ratios, and the temporal window for lesion formation. RESULTS: Illness, single bouts, or cumulative episodes lasting over 1 month is associated with higher odds of CO; individuals who were never sick have lower odds of having PH. This relationship was consistent for fatal and incidental illnesses that did not cause death. The developmental window for CO formation appears to close at 8 years. CONCLUSIONS: Those ill for over 1 month are more likely to have CO/PH than those with acute illnesses. Some individuals lived sufficiently long to form CO/PH but died of illness. Others with lesions died of circumstances unrelated to disease. This indicates hidden variation in robusticity even among ill individuals with CO/PH, which is vital in interpreting lesion frequencies in the archeological record.

Role of risk factors, scoring systems, and prognostic models in predicting the functional outcome in meningioma surgery: multicentric study of 552 skull base meningiomas.

Despite the importance of functional outcome, only a few scoring systems exist to predict neurologic outcome in meningioma surgery. Therefore, our study aims to identify preoperative risk factors and develop the receiver operating characteristics (ROC) models estimating the risk of a new postoperative neurologic deficit and a decrease in Karnofsky performance status (KPS). A multicentric study was conducted in a cohort of 552 consecutive patients with skull base meningiomas who underwent surgical resection from 2014 to 2019. Data were gathered from clinical, surgical, and pathology records as well as radiological diagnostics. The preoperative predictive factors of functional outcome (neurologic deficit, decrease in KPS) were analyzed in univariate and multivariate stepwise selection analyses. Permanent neurologic deficits were present in 73 (13.2%) patients and a postoperative decrease in KPS in 84 (15.2%). Surgery-related mortality was 1.3%. A ROC model was developed to estimate the probability of a new neurologic deficit (area 0.74; SE 0.0284; 95% Wald confidence limits (0.69; 0.80)) based on meningioma location and diameter. Consequently, a ROC model was developed to predict the probability of a postoperative decrease in KPS (area 0.80; SE 0.0289; 95% Wald confidence limits (0.74; 0.85)) based on the patient's age, meningioma location, diameter, presence of hyperostosis, and dural tail. To ensure an evidence-based therapeutic approach, treatment should be founded on known risk factors, scoring systems, and predictive models. We propose ROC models predicting the functional outcome of skull base meningioma resection based on the age of the patient, meningioma size, and location and the presence of hyperostosis and dural tail.

Clinical Characteristics and Prognostic Analysis of Osteolytic and Hyperostosis Sphenoid Orbital Meningiomas: A Single-Center Experience.

Reactive hyperostosis of spheno-orbital meningiomas (SOMs) often occurred in the sphenoid wing, while osteolytic SOMs (O-SOMs) were rarely discussed. This study preliminarily evaluated the clinical characteristics of O-SOMs and analyzed prognostic factors affecting the recurrence of SOMs. We retrospectively analyzed the medical records of consecutive patients who underwent surgery for a SOM between 2015 and 2020. According to the bone changes of sphenoid wing, SOMs were divided into O-SOMs and hyperostosis SOMs (H-SOMs). A total of 31 procedures were performed in 28 patients. All cases were treated by pterional-orbital approach. It was confirmed that 8 cases were O-SOMs and the other 20 cases were H-SOMs. Total tumor resection was performed in 21 cases. There were 19 cases with Ki 67 ≥3%. The patients were followed up for 3 to 87 months. Proptosis improved in all patients. All O-SOMs had no visual deterioration, while 4 H-SOMs cases had visual deterioration. There was no significant difference in clinical outcomes between the two types of SOM. The recurrence of SOM was related to the degree of resection, but not to the type of bone lesions, invasion of cavernous sinus and Ki 67.

Increased Hemichannel Activity Displayed by a Connexin43 Mutation Causing a Familial Connexinopathy Exhibiting Hypotrichosis with Follicular Keratosis and Hyperostosis.

Mutations in the GJA1 gene that encodes connexin43 (Cx43) cause several rare genetic disorders, including diseases affecting the epidermis. Here, we examined the in vitro functional consequences of a Cx43 mutation, Cx43-G38E, linked to a novel human phenotype of hypotrichosis, follicular keratosis and hyperostosis. We found that Cx43-G38E was efficiently translated in Xenopus oocytes and localized to gap junction plaques in transfected HeLa cells. Cx43-G38E formed functional gap junction channels with the same efficiency as wild-type Cx43 in Xenopus oocytes, although voltage gating of the gap junction channels was altered. Notably, Cx43-G38E significantly increased membrane current flow through the formation of active hemichannels when compared to wild-type Cx43. These data demonstrate the association of increased hemichannel activity to a connexin mutation linked to a skeletal-cutaneous phenotype, suggesting that augmented hemichannel activity could play a role in skin and skeletal disorders caused by human Cx43 mutations.

[Domestic software, medical devices and materials in surgery for hyperostotic craniofacial meningiomas]. / Primenenie otechestvennogo programmnogo obespecheniya, meditsinskikh izdelii i materialov v khirurgii giperostoticheskikh kraniofatsial'nykh meningiom. (Klinicheskii sluchai i obzor literatury).

OBJECTIVE: The modern concept of resection of hyperostotic craniofacial meningiomas involves the desire for one-stage surgery with excision of tumor and simultaneous extensive skull defect closure. MATERIAL AND METHODS: The authors present skull defect closure with an individual implant after resection of cranioorbital meningioma in a 61-year-old man. The neoplasm was accompanied by exophthalmos and eyelid edema. The patient underwent simultaneous microsurgical resection and skull reconstruction with an individual implant. At discharge (7 days after surgery), exophthalmos regressed to 3 mm. After 3 months, ophthalmologist revealed complete regression of exophthalmos. RESULTS: Domestic software and 3D printers were used for implant modeling and preparing the necessary physical models and molds. We intraoperatively used domestic polymer and titanium fixation systems for manufacturing and fixation of implant. CONCLUSION: This clinical case confirms that resection of hyperostotic craniofacial meningioma with simultaneous bone defect closure using domestic analogues of software, technical equipment, materials and methods is possible at all stages of this procedure.

[Ankylosing hyperostosis Forestier, simulating a neoplasm of the larynx]. / Ankiloziruyushchii giperostoz Forest'e, simulirovavshii novoobrazovanie gortanoglotki.

RELEVANCE: Forestier syndrome, despite its appearance as an independent disease in the 60s of the last century, remains as difficult to diagnose. This is due to a number of factors: age group, late treatment, insufficient knowledge of pathology. The timely detection of pathology is complicated by the similarity of the clinical picture in the early stages of its manifestation with a number of orthopedic diseases. OBJECTIVE: To present a description of the clinical observation of Forestier syndrome. MATERIAL AND METHODS: The material for this work was a clinical case of a person who applied to the Loginov Moscow Clinical Scientific Center with a directional oncological diagnosis of the larynx and a preemptively installed tracheostomy. RESULTS: The patient underwent surgical treatment in the form of removal of overgrown bone osteophytes of the thoracic spine with simultaneous disappearance of symptoms of the disease. CONCLUSION: This clinical observation clearly demonstrates the need for a comprehensive analysis of the clinical situation as a whole with a careful assessment of all factors that can influence it and the process of forming a diagnosis. Knowledge of conditions that can mimic a tumor lesion is extremely important for oncologists of all specialties. This allows you to avoid an erroneous diagnosis and choosing the wrong, possibly crippling treatment tactics. It should also be remembered that the oncological diagnosis is based, first of all, on morphological confirmation of the tumor process with a detailed assessment of the data of all additional imaging research methods.

Pro and contra: is synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) a spondyloarthritis variant?

PURPOSE OF REVIEW: The purpose of this review is to present the up-to-date evidence on the epidemiology, pathogenesis, musculoskeletal manifestations, and imaging of the synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome and to discuss its relationship with spondyloarthritis (SpA). RECENT FINDINGS: SAPHO is a rare inflammatory disorder of bone, joints, and skin, with a worldwide distribution that predominantly affects the middle-age adults. The hallmark of the syndrome is a constellation of sterile inflammatory osteitis, hyperostosis, and synovitis involving the anterior chest wall, associated with acneiform and neutrophilic dermatoses, such as palmoplantar pustulosis and severe acne. The axial skeleton, sacroiliac, and peripheral joints can be involved in a similar fashion to SpA. The pathogenesis of the syndrome is multifactorial. The diagnosis is mainly based on the clinical and typical radiological features. The treatment approach is based on the off-label use of antibiotics, bisphosphonates, disease-modifying antirheumatic drugs, and anticytokine biologics. SUMMARY: The SAPHO syndrome shares common features with SpA-related diseases, yet also shows some unique pathogenetic and clinical features. The nosology of SAPHO remains a subject of controversy, awaiting further research into the pathogenetic and clinical aspects of this syndrome. A better understanding of these aspects will improve the diagnostics and clinical care of patients with SAPHO.

Triad of hypovitaminosis A, hyperostosis, and optic neuropathy in males with autism spectrum disorders.

BACKGROUND: Persons with autism spectrum disorder (ASD) can have restrictive diets due to stereotyped behaviors. These restrictive diets can manifest with nutritional deficiencies, such as Vitamin A deficiency. The most frequent manifestation of hypovitaminosis A is vision loss secondary to xerophthalmia. Here the authors report six cases of males with a clinical triad of hypovitaminosis A, cranial hyperostosis, and optic neuropathy. METHODS: A retrospective case series of six males (ages 5-17 years old) with ASD who presented with several weeks of vision loss and nyctalopia were reviewed. RESULTS: All six subjects were found to have a barely detectable Vitamin A level (<10 mcg/dL). Three of the six cases had elevated protein (45.9-74.0 mg/dL) in their CSF. MRI imaging demonstrated mild T2 enhancement of bilateral optic nerve sheaths and CT showed diffuse skull hypertrophy. Upon further history collection, all subjects had a very limited food repertoire with major nutritional deficiencies. Subjects were prescribed high doses of vitamin A and most were noted to have improved vision at follow-up, and all had resolution of imaging abnormalities on repeat scans. No common genetic variant was identified in patients with expanded genetic sequencing. CONCLUSIONS: We present a clinical triad of hypovitaminosis A, cranial hyperostosis, and optic neuropathy in six males with ASD. Skull abnormalities and xeropthalmia likely contributed to the development of vision loss.

Retinoid-induced skeletal hyperostosis in disorders of keratinization.

For disorders of keratinization, topical treatment alone may be ineffective, and systemic retinoid therapy may be indicated. Treatment with systemic retinoids (acitretin, isotretinoin and alitretinoin) has been shown to be effective in reducing disease severity; however, potentially rare adverse effects (AEs) may occur, including hyperostotic skeletal changes. The true prevalence of this AE in adult patients administered life-long therapy is unknown. We identified 3 of 127 (2.4%) patients (with ichthyosis or Darier disease) who had been prescribed isotretinoin with or without acitretin, and who developed radiological signs and clinical symptoms of hyperostosis and ligamentous ossification. This clinical review highlights the significance of retinoid-induced skeletal hyperostosis in patients prescribed long-term, high-dose retinoid therapy for disorders of keratinization. Patients commencing systemic retinoid therapy, particularly women of childbearing age, should be counselled about this important and potentially serious AE, especially if long-term treatment is indicated.

Successful treatment of synovitis, acne, pustulosis, hyperostosis and osteitis syndrome with ixekizumab.

We report the use of ixekizumab in treating synovitis, acne, pustulosis, hyperostosis and osteitis (SAPHO) syndrome, the first such report to our knowledge. The patient presented with palmoplantar pustulosis and sternoclavicular joint pain, which was markedly improved with ixekizumab treatment.

Long-term effect of bilateral anterior elevation of occlusion on the temporomandibular joints.

OBJECTIVE: Incisors tubed prosthesis with bilateral anterior elevation (BAE) relation had been reported to stimulate the proliferative response in the mandibular condylar cartilage of mice, thus the prosthetic occlusion elevation had been proposed to treat cartilage degeneration. Currently, we aimed to detect the long-term effect of BAE on temporomandibular joints (TMJs). MATERIALS AND METHODS: Twelve 6-week-old female mice were assigned to age-matched control and BAE groups (n = 6). Micro-CT images and the macro- and micro-morphology of the mandibular condyles were analyzed at 29 weeks. RESULTS: Compared with the age-matched controls, in BAE group, there were loss of subchondral cortical bone and heavy loss of the subchondral trabecular bone at the superior sites of the TMJ condyles, but hyperostosis at the inferior sites as revealed by micro-CT images and histological slices. In BAE group, cartilage thickness and matrix area were increased with upregulated expression of type II, type X collagen, and Ki67, but the expression of cleaved caspase-3 was downregulated (all, p < 0.05). CONCLUSION: In addition to cartilage thickening, long-term BAE induces loss of the subchondral cortical bone and heavy loss of the underneath subchondral trabecular bone, but hyperostosis further underneath. Using BAE as a treatment remains double-edged.

Transcranial MR-Guided Focused Ultrasound and Hyperostosis Calvariae Diffusa: Case Report and Systematic Review of the Literature.

We describe a 74-year-old male with intractable essential tremor (ET) and hyperostosis calvariae diffusa who was unsuccessfully treated with magnetic resonance-guided focused ultrasound (MRgFUS). A computed tomography performed prior to the procedure demonstrated a skull density ratio (SDR) of 0.37 and tricortical hyperostosis calvariae diffusa. No lesion was evident on post-MRgFUS MRI, and no improvement in the patient's hand tremor was noted clinically. We systematically reviewed the literature to understand outcomes for those patients with hyperostosis who have undergone MRgFUS. A comprehensive literature search using the PubMed, Cochrane, and Google Scholar databases identified 3 ET patients with hyperostosis who failed treatment with MRgFUS. Clinical findings, skull characteristics, treatment parameters, and outcomes were summarized, demonstrating different patterns/degrees of bicortical hyperostosis and variable SDRs (i.e., from 0.38 to ≥0.45). Although we have successfully treated patients with bicortical hyperostosis frontalis interna (n = 50), tricortical hyperostosis calvariae diffusa appears to be a contraindication for MRgFUS despite acceptable SDRs.

Incidental posterior rib hyperostosis on chest CT: incidence and etiology.

OBJECTIVE: Incidental rib hyperostosis is defined as asymmetric cortical thickening and sclerosis of the medial posterior ribs and is important because it may lead to unnecessary laboratory testing, additional imaging and occasionally biopsy. The purpose of this study is to identify the incidence of rib hyperostosis within different patient groups known to have an increased propensity towards osteophyte formation and ankylosis. METHODS: This study was a retrospective cohort study reviewing chest CT examinations in a control group of patients over 50 years old and three different patient populations: psoriatic arthritis, ankylosing spondylitis, and diffuse idiopathic skeletal hyperostosis (DISH). Each CT was evaluated by an attending musculoskeletal and cardiothoracic radiologist to identify rib hyperostosis, osteophyte formation, ankylosis, and spinal curvature. Two senior radiology residents also performed consensus reads and inter-reader reliability was calculated between the two groups. RESULTS: Two hundred eighty-two individuals were included in the study of which 38 (13.5%) had at least one hyperostotic rib. The ankylosing spondylitis population and the DISH population had the highest incidence of rib hyperostosis with a relative risk of 5.6 (p = 0.012) and 5.3 (p = < 0.001) when compared to the control group. There was good inter-reader reliability for the presence of rib hyperostosis with a kappa estimate of 0.739. CONCLUSION: Incidentally detected rib hyperostosis is most likely the sequela of abnormal stress on the ribs secondary to rib hypomobility from fusion at the costovertebral joint. The incidence of rib hyperostosis is markedly increased in the DISH and ankylosis spondylitis study populations.