Quantitative assessment of the posttreatment lung volume changes in patients with flail chest on computed chest tomography images

Complications encountered in the chronic phase in flail chest patients are a decrease in lung volume due to chest wall deformities and secondary restrictive respiratory function disorders. The aim of the study was to determine the differences in lung volume changes between flail chest patients who were treated non-surgically and those who were treated with surgical stabilisation. The study was conducted on twenty patients who applied to our clinic and were diagnosed with flail chest. There were ten patients in the non-surgically treated group and ten in the surgical stabilisation group. Computed tomography (CT) images of the patients were received before the treatment and in the third post-operative month. Total lung volumes were estimated on CT images using the planimetry method of the Cavalieri principle. The relationship between the treatment method and volume changes was analysed. While the total lung volume increased 12.9% post-operatively in the non-surgically treated group, it increased 36.9% in the surgical stabilisation group (p<0.05). In those cases of hemithorax affected by trauma, the increase in volume in the surgical stabilisation group was 41.6 (34.6%), but it was 7.7 (10%) in the non-surgically treated group (p<0.05). In the contralateral hemithorax, the increase observed in the stabilisation group was 42.6 (39.2%) while the increase in the non-surgical treated group was 19.6 (13.9%) (p>0.05). Our findings showed that the post-operative total lung volume increase in the surgically treated group of patients was greater than that of the conservative group. If there are no preventive factors for the surgical approach, surgical rib stabilisation could be the primary choice of treatment in flail chest patients.

Does Costal Cartilage Resection Reduce Lung Volume ? (An Experimental Stereological Study)

Background: Surgical treatment of chest wall deformities is done with costal cartilage resection in selected patients in adolescence. In this study, we evaluated the effect of costal cartilage resections on the lung volume by using computed tomography with stereologically. Methods: In this study, sixteen 4-weeks-old New Zealand rabbits were employed. Young subjects were preferred to evaluate the effect of the operation on the growth process. In order to avoid postoperative complications, only 2 costal cartilage resection was performed. The surgical group was resected to the right 4 and 5 costal cartilages (n = 8). The group that was not operated was accepted as the control group (n=8). The growth of the subjects was followed. Computed thorax tomography (CTT) scans of all animals were performed preoperatively and at the 4th postoperative week. Estimation of pre- and postoperative lung volumes was performed with the Cavalieri principle. Results: In the control group followed up during growth, bilateral lung volume was increased (15.75% and 20.62% respectively right and left lungs). In the surgical group, both the surgical side and the opposite lung volume decreased after costal cartilage resection (20.09% and 1.07% respectively right and left lungs). Conclusions: Even though the number of resected cartilage was limited, total lung volume decreased after costal cartilage resection. In the treatment of chest wall deformities, costal cartilage resection should be considered as the last option in children.

The volume fraction values of the brain compartments using the Cavalieri principle and a 3T MRI in brachycephalic and mesocephalic dogs

This study was aimed at: 1) estimating the volume and the volume fraction values of brain ventricles, grey matter and white matter with the Cavalieri principle and 2) creating three-dimensional reconstruction models of the brain ventricles by using magnetic resonance imaging. The brain structures of dogs were scanned with a 3T magnetic resonance system. The volumes of the total brain, the grey matter, the white matter, the lateral ventricle, the third ventricle, the cerebral aqueduct and the fourth ventricle of both sides were estimated separately by using a combination of the Cavalieri principle and the point-counting method. In addition to that, magnetic resonance images of dog brains were uploaded to the 3D slicer software to design the three-dimensional reconstruction models. The mean volume fraction values of the left and right lateral ventricle, third ventricle, cerebral aqueduct, and fourth ventricle were 1.83 ± 0.14%, 1.75 ± 0.1%, 0.7 ± 0.07%, 0.2 ± 0.04%, and 1 ± 0.32% for the brachycephalic dogs and 1.69 ± 0.04%, 1.66 ± 0.03%, 0.91 ± 0.03%, 0.27 ± 0.05%, and 0.71 ± 0.15% for the mesocephalic dogs, respectively. There was no statistically significant difference between the brachycephalic and mesocephalic dogs in all the volume fraction values (P &gt; 0.05). This study showed the volume and the volume fraction values of the brain ventricles and the structures in the different types of the dogs’ head shapes. These volume fraction values can be essential data for determining some diseases. Magnetic resonance imaging can be used for precise volume estimations in combination with the Cavalieri principle and the point-counting method.

Aspects of subregion holographic complexity

This is a mini-review about the rapidly growing subject of dual holographic complexity (HC) for subsystems in conformal field theory (CFT) using a subregion volume enclosed by the entangled area in the dual bulk theory. This proposal is named as HC = volume. We use this proposal to compute the HC for different geometries in bulk theory. Because this HC quantity diverges as a result of the existence of the UV cutoff in the CFT, we proposed a suitable regularization scheme by subtracting the contribution of the background (pure) AdS spacetime from the deformation of the AdS geometry. Furthermore, the time-dependent geometries are investigated using the AdS/CFT proposal and hence, we proposed a time-dependent copy for HC in such nonstatic geometries. As an attempt to make a relation between HC and holographic entanglement entropy (HEE), inspired from the pure geometrical origins, we showed that HC and HEE which are duals to different volumes/areas in the bulk theory would be connected in a universal form for a general deformation AdS geometry (called holographic Cavalieri principle). As a pioneering idea we build a holographic model for [Formula: see text] critically in black holes via regularized HC as the dual thermodynamic volume. The second-order phase transitions in two-dimensional holographic superconductors is explained by using the regularized HC as an order parameter. All the results presented in this mini-review are collected from the list of published works of the first author of this paper. In several cases, we gave further explanation and clarification to make the ideas more understandable to the community. Other proposals for complexity like complexity as on shell action are not included in this review paper.

Holographic Cavalieri principle as a universal relation between holographic complexity and holographic entanglement entropy

In this paper, we will propose a universal relation between the holographic complexity (dual to a volume in AdS) and the holographic entanglement entropy (dual to an area in anti-de Sitter (AdS)). We will explicitly demonstrate that our conjuncture holds for all metrics asymptotic to [Formula: see text], and then argue that such a relation should hold in general due to the AdS version of the Cavalieri principle. We will demonstrate that it holds for Janus solution, which have been recently been obtained in type IIB string theory. We will also show that this conjecture holds for a circular disk. This conjecture will be used to show that the proposal that the complexity equals action and the proposal that the complexity equals volume can represent the same physics. Thus, using this conjecture, we will show that the black holes are fastest computers, using the proposal that complexity equals volume.

The estimation of bone cyst volume using the Cavalieri principle on computed tomography images

Purpose: To evaluate the volume of bone cyst using the planimetry method of the Cavalieri principle. Methods: A retrospective analysis was carried out on data from 25 computed tomography (CT) images of patients with bone cyst. The volume of the cysts was calculated by two independent observers using the planimetry method. The procedures were repeated 1 month later by each observer. Results: The overall mean volume of the bone cyst was 29.25 ± 25.86 cm3. The mean bone cyst volumes calculated by the first observer for the first and second sessions were 29.18 ± 26.14 and 29.27 ± 26.19 cm3, respectively. The mean bone cyst volumes calculated by the second observer for the first and second sessions were 29.32 ± 26.36 and 29.23 ± 26.36 cm3, respectively. Statistical analysis showed no difference and high agreement between the first and second measurements of both observers. The Bland–Altman plots showed strong intraobserver and interobserver concordance in the measurement of the bone cyst volume. The mean total time necessary to obtain the cyst volume by the two observers was 5.27 ± 2.30 min. Conclusion: The bone cyst of the patients can be objectively evaluated using the planimetry method of the Cavalieri principle on CT. This method showed high interobserver and intraobserver agreement. This volume measurement can be used to evaluate cyst remodeling, including complete healing and cyst recurrence.

Endocranial and masticatory muscle volumes in myostatin-deficient mice

Structural and functional trade-offs are integral to the evolution of the mammalian skull and its development. This paper examines the potential for enlargement of the masticatory musculature to limit the size of the endocranial cavity by studying a myostatin-deficient mouse model of hypermuscularity (MSTN−/−). The study tests the null prediction that the larger MSTN−/− mice have larger brains compared with wild-type (WT) mice in order to service the larger muscles. Eleven post-mortem MSTN−/− mice and 12 WT mice were imaged at high resolution using contrast enhanced micro-CT. Masticatory muscle volumes (temporalis, masseter, internal and external pterygoids) and endocranial volumes were measured on the basis of two-dimensional manual tracings and the Cavalieri principle. Volumes were compared using Kruskal–Wallis and Student's t -tests. Results showed that the masticatory muscles of the MSTN−/− mice were significantly larger than in the WT mice. Increases were in the region of 17–36% depending on the muscle. Muscles increased in proportion to each other, maintaining percentages in the region of 5, 10, 21 and 62% of total muscle volume for the external ptyergoid, internal pterygoid, temporalis and masseter, respectively. Kruskal–Wallis and t -tests demonstrated that the endocranial volume was significantly larger in the WT mice, approximately 16% larger on average than that seen in the MSTN−/− mice. This comparative reduction of MSTN−/− endocranial size could not be explained in terms of observer bias, ageing, sexual dimorphism or body size scaling. That the results showed a reduction of brain size associated with an increase of muscle size falsifies the null prediction and lends tentative support to the view that the musculature influences brain growth. It remains to be determined whether the observed effect is primarily physical, nutritional, metabolic or molecular in nature.

Sensory Neuron Death After Upper Limb Nerve Injury and Protective Effect of Repair

BACKGROUND: Extensive death of sensory neurons after nerve trauma depletes the number of regenerating neurons, contributing to inadequate cutaneous innervation density and poor sensory recovery. Experimentally proven neuroprotective neoadjuvant drugs require noninvasive in vivo measures of neuron death to permit clinical trials. In animal models of nerve transection, magnetic resonance imaging (MRI) proved a valid tool for quantifying sensory neuron loss within dorsal root ganglia (DRG) by measuring consequent proportional shrinkage of respective ganglia. OBJECTIVE: This system is investigated for clinical application after upper limb nerve injury and microsurgical nerve repair. METHODS: A 3-T clinical magnet was used to image and measure volume (Cavalieri principle) of C7-T1 DRG in uninjured volunteers (controls, n = 14), hand amputees (unrepaired nerve injury, n = 5), and early nerve repair patients (median and ulnar nerves transected, microsurgical nerve repair within 24 hours, n = 4). RESULTS: MRI was well tolerated. Volumetric analysis was feasible in 74% of patients. A mean 14% volume reduction was found in amputees' C7 and C8 DRG (P &lt; .001 vs controls). Volume loss was lower in median and ulnar nerve repair patients (mean 3% volume loss, P &lt; .01 vs amputees), and varied among patients. T1 DRG volume remained unaffected. CONCLUSION: MRI provides noninvasive in vivo assessment of DRG volume as a proxy clinical measure of sensory neuron death. The significant decrease found after unrepaired nerve injury provides indirect clinical evidence of axotomy-induced neuronal death. This loss was less after nerve repair, indicating a neuroprotective benefit of early repair. Volumetric MRI has potential diagnostic applications and is a quantitative tool for clinical trials of neuroprotective therapies.