Progressive bilateral thinning of the parietal bones

A case of bilateral thinning of the cranial bones in an elderly individual

BACKGROUND

Bilateral thinning of the parietal bone is a condition that has been known since the 18th century, with several names being given since its discovery. The aetiology is unknown but there are numerous theories. Although this condition is rarely encountered, its clinical significance may be relevant to traumatic cases.

OBJECTIVES

This study aims to present a case of bilateral thinning observed in the cranium of an 87-year elderly female, which was assessed macroscopically and radiologically to visualize the exact parameters of the thinned areas to discuss a plausible cause and aetiology of the condition.

METHODS

During maceration for teaching purposes, the cranium was removed and assessed macroscopically. A micro-CT was then taken to determine the exact size and cranial thickness of the lesions.

RESULTS

A differential diagnosis was established which included an unknown aetiology or Gorham-Stout disease. In addition, it was noted that metabolic factors, such as malnutrition and metabolic acidosis, should be considered as factors for increasing its severity.

CONCLUSION

Case studies on the presence of bilateral thinning of the parietal bones has been reported in various countries, while no case studies could be found reporting the presence of bilateral thinning on both the parietal and occipital bones. The combination of thinning reported in this study may suggest increased severity of a more advanced state of the condition.

A coddling of the sagittal suture: inequality in spring-assisted expansion

PURPOSE

We examined differences in long-term morphometric outcomes of spring-mediated cranioplasty (SMC) for various forms of isolated nonsyndromic sagittal craniosynostosis.

METHODS

A retrospective review was performed of children who underwent SMC from 2011 to 2020 at the Children's Hospital of Philadelphia. Cephalic indices (CI), Whitaker grades, parietal bone thickness, and degree of suture fusion were assessed. Frontal bossing and vertex-nasion-opisthocranion (VNO) angles were compared to a normal control group.

RESULTS

Fifty-four subjects underwent surgery at age 3.6 ± 1.0 months with follow-up of 6.3 ± 1.8 years. Mean CI was 75.2 ± 4.1 at 5.9 ± 2.0 years postoperatively. Mean CI were 75.8 ± 4.1 (n = 32), 76.4 ± 4.0 (n = 22), and 77.1 ± 4.8 (n = 11) at 5, 7, and 9+ years postoperatively, respectively. Three (5.6%) required reoperation for persistent scaphocephalic cranial deformity. Fifty-one (94.4%) were Whitaker Grade I. On physical examination, 12 (22.2%) demonstrated craniofacial abnormalities. At long-term follow-up, there were no differences in frontal bossing angle (102.7 ± 5.2 degrees versus 100.7 ± 5.6 degrees, p = .052) and VNO angle (44.9 ± 3.3 degrees versus 43.9 ± 2.2 degrees, p = .063) between study and control groups. Younger age at surgery predicted a lower Whitaker grade, more normalized VNO angle, and greater change in CI during active expansion. Increased percentage fused of the posterior sagittal suture predicted a higher Whitaker grade, while decreased anterior fusion was associated with frontal bossing and temporal hollowing.

CONCLUSIONS

Overall, children undergoing spring-mediated cranioplasty for sagittal craniosynostosis demonstrated maintenance of CI, favorable cosmetic outcomes, and a low reoperation rate at mid-term follow-up. Early intervention is associated with improved aesthetic outcomes, and regional fusion patterns may influence long-term craniofacial dysmorphology.

Long-Term Comparison of Two- and Three-Dimensional Computed Tomography Analyses of Cranial Bone Defects in Severe Parietal Thinning

Parietal thinning was detected in a 72-year-old with recurrent headaches. Quantification of bone loss was performed applying two- and three-dimensional methods using computerized tomographies. Two-dimensional methods provided accurate measurements using single-line analyses of bone thicknesses (2.13 to 1.65 and 1.86 mm on the left and 4.44 to 3.08 and 4.20 mm on the right side), single-point analyses of bone intensities (693 to 375 and 403 on the left and 513 to 393 and 411 Houndsfield Units on the right side) and particle-size analyses of low density areas (16 to 22 and 12 on the left and 18 to 23 and 14 on the right side). Deteriorations between days 0 and 220 followed by bone stability on day 275 were paralleled using the changed volumes of bone defects to 1200 and finally 1133 mm3 on the left side and to 331 and finally 331 mm3 on the right side. Interfolding as measurement of the bones' shape provided changes to -1.23 and -1.72 mm on the left and to -1.42 and -1.30 mm on the right side. These techniques suggest a stabilizing effect of corticosteroids between days 220 and 275. Reconstruction of computerized tomographies appears justified to allow for quantification of bone loss during long-term follow-up.

Two Cases of Frontal Variation of Idiopathic Calvarial Thinning-Therapeutic Effect of Denosumab and Romosozumab

Idiopathic calvarial thinning is a rare condition that causes progressive, painless thinning of the skull bones without systemic disease. We present 2 cases of idiopathic calvarial thinning involving the bifrontal region. Both patients exhibited forehead depression and had normal biochemical tests except for mild vitamin D deficiency. The first patient received treatment with denosumab for 3 years, showing no further progression of the skull thinning. The second patient was treated with denosumab for 3 years, followed by romosozumab for 1 year, resulting in no further progression and even slight recovery of the skull thickness. These cases demonstrate that idiopathic calvarial thinning can involve the bifrontal region and highlight the favorable treatment and prognosis with denosumab or romosozumab.

A case of coexisting hyperostosis frontalis interna and biparietal bone thinning

Incidental pathology of the skull is frequently detected on cross sectional imaging of the brain. In contrast to the common finding of hyperostosis frontalis interna, biparietal bone thinning is less common. A case of an 87-year-old woman showing coexistence of hyperostosis frontalis interna and biparietal bone thinning is presented. This coexistence has not been reported previously.

Biparietal osteodystrophy: Macroscopic appearance, computed tomography imaging and microarchitectural analysis

Anatomical or morphological variations of the skull bones usually do not attract much attention among forensic pathologists. However, these variations can sometimes be an important marker in forensic identification of a person or represent a missing piece when solving a cranial trauma puzzle. In this article, we were interested in peculiar presentation of the thinning of both parietal bones (biparietal osteodystrophy). The course and etiology of this condition still remain unknown. In three autopsy cases with biparietal osteodystrophy (three females aged 95, 90 and 83) and no head trauma, we used conventional (CT) and microcomputed tomography (micro-CT) imaging of the skull and parietal bone specimens containing normal bone, transitional zone and thinned bone with osteodystrophy. CT images demonstrated an oval-shaped resorptive parietal bone depression with smooth contours, without marginal osteosclerotic changes or involvement of cranial sutures. In the transitional zone, micro-CT scans showed a decrease in total bone thickness and the thickness of diplöe, while inner and outer tables showed increased porosity. At the site of maximal thinness of the parietal bone, inner and outer tables fused and formed a thin layer of cortical bone. Skull thinning appeared due to the reduced thickness of diplöe, leading to egg-shell thinning in the central area of the parietal bones. A forensic pathologist should be familiar with this benign condition in order not to confuse it with resorptive bone diseases.

A Severe Case of Biparietal Thinning in a Medieval Skull From a Northern Italy Necropolis

ABSTRACT

This study aims at presenting a case of symmetrical and bilateral thinning observed in a skull belonging to the skeleton of a mature woman from the medieval cemetery of Caravate (north Italy). Macroscopical, radiological, and histological analyses were performed to investigate the condition. The analyses allowed us to detect a progressive loss of both the outer table and the diploe, and the sparing of the inner table. As a controversial condition in the clinical and paleopathological literature, this case poses some difficulties in discussing the differential diagnosis. However, the sex determination, estimation of the age-at-death and different characteristics observed at the level of the postcranial bones, in particular the fractures recorded on different vertebral bodies, allowed us to correlate the biparietal thinning found in this subject to ageing and osteoporosis.

Focal Idiopathic Calvarial Thinning: A Condition of Uncertain Prevalence and Significance

ABSTRACT

Focal thinning of the calvarial bones unrelated to an underlying systemic disease is uncommon. Of such cases documented in the medical literature, most are bilateral parietal bone thinning, which tends to affect elderly females and results in bilateral symmetric, regularly shaped depressions of the skull. The authors describe 2 cases of unilateral, focal, irregularly shaped calvarial thinning in adolescent males that occurred without an obvious precipitating incident and were unrelated to systemic disease, a known syndrome or previous trauma. The nature and physical parameters of the deformities are demonstrated here and specific historic features such as age of onset and mode of obstetric delivery are explored. The clinical significance and potential pathogenesis of this finding is unclear, though these cases are relevant in highlighting a novel presentation that we henceforth term focal idiopathic calvarial thinning.

Characterization of Bilateral Parietal Thinning

BACKGROUND

Bilateral parietal thinning (BPT) of the calvarium is uncommon but can lead to significant morbidity, including pain or communication through the thinned bone. This study aimed to define and characterize a novel grading system for BPT.

METHODS

Coronal CT scans of patients with BPT were retrospectively analyzed and anatomic measurements were taken including (1) thinning ratio, defined as calvarial thickness at the thinnest point divided by the average thickness of the surrounding bone and (2) width of the defect. In addition, patient demographics and comorbidities were collected.

RESULTS

Forty-three patients were identified with BPT, with an average age of 73 ± 16 years and 74% were female. The authors' novel grading scheme based on depth of calvarium involvement was found to be significantly correlated to thinning ratio (P < 0.001) and width (P < 0.001). When controlling for comorbidities, increasing age (P = 0.044) was the only significant independent risk factor associated with thinning ratio. With respect to defect size, when controlling for comorbidities, both hypertension (P = 0.025) and increasing age (P = 0.024) were found to be significant independent risk factors related to increasing defect size. Twenty patients (47%) had multiple CT scans (range 5 month-5 year interval). In this group, patients had an average of 0.66 ± 0.11 mm decrease in parietal thickness per each year of increasing age, showing progressive parietal thinning with time.

CONCLUSION

This study proposes a novel quantitatively-characterized grading scheme for BPT. The authors' results indicate that when controlling for comorbidities, BPT thinning is associated with increasing age, while defect width is associated with increasing age and hypertension. This grading scheme can help to diagnose, classify, and monitor patients with parietal bone thinning.

Reprint of-Differential diagnosis: Trepanation

Trepanation is the scraping, cutting, or drilling of an opening (or openings) into the neurocranium. World surveys reveal that a number of ancient cultures experimented with cranial surgery, and that in some areas these practices continued into modern times. Archaeological discoveries of possible trepanations continue to be made, often from geographic areas or time periods from which the practice was not previously known. Unfortunately, most of these reports describe single crania with healed defects interpreted as trepanations. When evaluating a possible trepanation in a skull that lacks medical history or comes from an archaeological context where there is no other evidence that such operations were performed, a thorough differential diagnosis is essential. Identification of unhealed trepanations is a relatively straightforward exercise, since tool marks provide direct evidence of surgical intervention. A confident diagnosis is more difficult in healed defects of the skull, where the mechanism that produced an opening may be obscured by bone remodeling. There are many possible causes of defects of the skull vault, including congenital and developmental anomalies, trauma, infection, neoplasm, and taphonomic damage. For this reason, a careful differential diagnosis is essential for identifying surgical intervention and distinguishing it from cranial defects caused by other mechanisms.

Death due to fracture of thin calvarial bones after a fall: A forensic approach

A 45-year-old male was autopsied. He had fallen backwards from a two-stairs height to the ground and passed away. A skull fracture was detected in the left occipital area, extending up to the left side of the skull base. The patient's death occurred due to the very low thickness of the calvarial bones, which led to the aforementioned fracture, and in turn resulted in subarachnoid hemorrhage and death. The cortical thickness was measured and compared with average values at standardized points. Uniform bone thinning was confirmed rather than localized. Calvarial thinning may result from various conditions. In the present case study, however, the exact mechanism which led to the low thickness of the calvarial bones of the patient is undetermined. Death due to the susceptible structure and fracture of calvarial bones has rarely been reported throughout relevant literature.

Biparietal Thinning: Accidental Death by a Fall from Standing Height

Biparietal thinning resulting in bilateral and symmetrical resorption and loss of thickness of the parietal bones is an uncommon to rare condition in the anthropological and clinical literature. This enigmatic condition of unknown etiology was first reported in the 18th century and has been variously described as a nonmetric trait, anatomical variant, anomaly, and pathology. Biparietal thinning presents grossly and radiographically as oval-shaped depressions in 0.25-0.8% and 0.4-0.5% of individuals and with a higher frequency in females over the age of 60 years. A review of the literature revealed only one example of cranial trauma associated with biparietal thinning and none of fatal trauma associated with this condition. This case reports a rare example of fatal trauma in an elderly man that resulted from a backward fall from a standing height and highlights the increased risk of craniocerebral trauma in individuals with this condition.

New cases of trepanations from the 5th to 3rd millennia BC in Southern Russia in the context of previous research: Possible evidence for a ritually motivated tradition of cranial surgery?

OBJECTIVES

It is a big challenge to diagnose the motives behind trepanations in prehistoric crania. Surgical-therapeutic attempts may be apparent by the presence of fractures, however, ritual or nonmedical motives are rarely supported by visible evidence in the bones. This article presents data on the trepanations of several individuals from South Russia dating to the Eneolitic and Bronze Age that may indicate a ritual procedure. In these crania an operation was performed in the identical location, the midline, furthermore in one of the most dangerous places, on the obelion. No evidence for traumatic or other pathological reasons for performing the operations was observable.

MATERIAL AND METHODS

Investigations of two nearby areas of South Russia revealed 13 individuals showing complete perforations in the midline of the cranium. Another one, displaying a depression in the same place, primarily diagnosed as an incomplete trepanation, is discussed considering all differential diagnoses. The trepanations were investigated macroscopically, by plain radiography and computed tomography. The lesions were described in detail, including data on technique, position, size, shape, state of healing, and complications.

RESULTS

Males and females received the operation between the age of 10 years and mature/senile age. Only grooving and scraping techniques were used and their application differed between sexes. The majority of the patients survived the intervention for a long time.

DISCUSSION

The region of Southern Russia seems to be a center for special trepanations performed by skilled surgeons, the specific position of the perforations implying more a ritual than therapeutic reason for trepanning. Am J Phys Anthropol 160:665-682, 2016. © 2016 Wiley Periodicals, Inc.

Variation in large ectocranial lesions from pre-Columbian Kuelap, Peru

This paper analyses a diverse collection of previously undescribed cranial lesions observed from 42 individuals from the pre-Columbian site of Kuelap, eastern montane, Peru. I describe the presence of cranial lesions, their location on the vault location, shape, and size of affected area, and evidence of remodeling. Seventeen percent of the total cranial sample demonstrates similar superficial cranial lesions including males (25/117, 21.4%) and females (14/74, 18.9%), and adolescents (3/27, 11%). Most lesions are narrow ovals or long and leaf-shaped, with depression of the external cranial vault. While some are well-healed and smooth-surfaced, others are more irregular with variable degrees of remodeling. The highest frequency is on the superior and posterior aspects of the vault, usually along the sagittal plane. Differential diagnoses are considered but no single pathology is clear for all cases. There are some common features consistent with active and healing osteitis and a few are directly associated with trepanation. General patterning suggests intentional treatment, perhaps even possible cauterization of scalp injuries or healed infections. These large cranial "scars" have not been observed at coastal Peruvian sites and may reflect specific regional conditions related to highland environmental factors, local medical treatments of cranial injuries, or population specific malformations.

Epidural hematoma after minor trauma on patient with biparietal osteodystrophy

Thinning of parietal bone bilaterally is extremely rare but well known phenomenon. Approximate prevalence is 0.4-0.5% according to radiological scans, case reports and anthropologic researches. Even though biparietal osteodystrophy occurs mostly in over 60-year-old women, it shows no special association with race or geographical area tendency. Current definition was changed by understanding that is a pathological situation, not an anatomical variety or result of growing old in time. Biparietal osteodystrophy may have an unusual presentation and treatment still remains unclear. We aim to present a patient with biparietal osteodystrophy associated with minor head trauma that caused parietal fracture and epidural hematoma underneath.