Mean Horizontal Dimension Research Articles

Measurement of Orbital Dimensions and Its Gender Related Differences in Various Ages of Pakistani Children

Purpose: To measure the orbital dimensions and their gender related differences at various ages in Pakistani children from birth to 12 years of age. Study Design: Cross sectional observational. Place and Duration of Study: Tibri Medical College and Hospital Karachi and National Institute of Child Health, Karachi from June 2022 to February 2023. Methods: Patients who underwent CT Scan head for any reason but with normal orbits were included in the study. The vertical and horizontal measurements were made for anterior, middle and posterior orbit in sagittal and axial views. Results: The mean age of the total sample of 176 children was 6.45±3.40 years. The mean horizontal dimension of the anterior side of the orbit was 28.31 mm for children aged 1-3 years, 30.63 mm for those aged 4-6 years, 32.22 mm for ages 6-9 years, and 32.93 mm for ages 10-12 years. These differences were statistically significant (p<0.05). A significant difference was observed in the mean vertical dimension for the middle and posterior sides across different age groups. There were significant differences in the vertical and horizontal dimensions of the anterior and middle sides of the orbits for children aged 1-3 years (p<0.05). However, for children aged 4-6 years, there were no significant differences between genders in any measured dimension (horizontal, vertical, or depth) (p>0.05). Conclusion: There is a phase of rapid growth from birth to 3 years of age, after which the orbit continues to grow slowly. Gender-related differences were more pronounced during this phase.

Efficacy of the Tent-Pole Technique in Horizontal Ridge Augmentation

Objective: To evaluate the efficacy of the technique for ridge augmentation prior to implant placement. Material and Methods: Six patients with nine sites presenting an initial ridge width of smaller than 4 mm were included in this study. The tent-pole technique (combination of osteosynthesis screws measuring 1.5 mm in diameter, ABBM, and resorbable collagen membrane) was applied at defect sites. After eight months of healing time, implants were placed in the treated sites. The primary outcomes (radiographic initial ridge width, re-entry ridge width, ridge width gain) were measured by cone-beam computed tomography in reference buccopalatal cross-sections and the secondary outcomes (clinical parameters) were recorded by a digital caliper at the first and second stages. Results: After grafting, the radiographic ridge width increased by 3.02 ± 1.11 mm (1.57-4.75 mm) at 2 mm below the crest and 3.32 ± 1.70 mm (0.23-5.66 mm) at 6 mm below the crest significantly (p< 0.05). For clinical results, the mean horizontal dimension gain was 3.21 ± 1.04 mm (1.83-4.57 mm), while the mean reduction in dimension was 0.38 ± 0.33 mm. These results were statistically significant (p<0.05). Uneventful healing and no infections or membrane exposure were recorded at all sites during the study process. Three of nine (33.33%) defect sites required additional bone grafting. Conclusion: The tent-pole technique is an effective method for increasing the horizontal ridge dimension, minimizing postoperative complications, and facilitating subsequent implant placement.

Lateral elongation of flat irregular pigment epithelial detachment: A novel optical coherence tomography biomarker in polypoidal choroidal vasculopathy.

Purpose:To explore novel Optical Coherence Tomography (OCT) biomarkers and precursor lesions in Polypoidal Choroidal Vasculopathy (PCV).Methods:This retrospective cohort study included 76 treatment naïve fellow eyes of PCV. Focus was given to analyse the various morphological changes in the clinically unaffected fellow retina during the follow-up period.Results:11 fellow eyes (14.47%) developed disease activity in the form of Sub Retinal Fluid (SRF) or Intra Retinal Fluid (IRF) within a mean follow-up of 17 months. All 11 eyes (100%) showed the presence of flat irregular pigment epithelial detachment (FIPED) and a peculiar property of lateral elongation of FIPED during disease activity. A positive correlation with the disease progression was found for the same (P < 0.0001). The mean horizontal dimension of the flat irregular PED at the enrolment was 1984 ± 376u and the mean expansion of FIPED at SRF formation was 461 ± 152u. ICG taken at the time of disease activity in the fellow eye revealed branching vascular network (BVN) in 9 (81.8%) eyes, polyps in 7 (63.6%) eyes, a combination of both in 5 (45.4%) eyes. Type one BVN with interconnecting channels showed faster disease progression than type two BVN. Eye tracking ICG illustrated that BVN corresponded to the FIPED in OCT and polypoidal lesions developed at the end of expanding FIPED.Conclusion:Flat irregular pigment epithelial detachment with its characteristic property of lateral elongation may be considered as a precursor lesion for PCV and as a novel OCT biomarker for the disease activity. Fellow eyes with FIPED need close monitoring to identify development of disease activity at the earliest.

A Limited Field Cone-beam Computed Tomography–based Evaluation of the Mental Foramen, Accessory Mental Foramina, Anterior Loop, Lateral Lingual Foramen, and Lateral Lingual Canal

IntroductionThe aim of this retrospective observational study was to evaluate the cone-beam computed tomographic (CBCT)-based characteristics of the mental foramen (MF), accessory mental foramen (AMF), anterior loop (AL), lateral lingual foramen (LLF), lateral lingual canal (LLC) and to explore any relationships between their characteristics. MethodsThe location and dimension of the MF; the incidence, location, and dimension of the AMF along with its distance to the MF; the presence and dimension of the AL; and the presence, location, angle of entry of the LLF and LLC, and its relation with the mandibular canal (MC) were evaluated in 109 CBCT scans. The data were analyzed descriptively, and associations were tested using the chi-square and analysis of variance tests. ResultsThe MF was most frequently located between the first and second mandibular premolar teeth (43.5%) or below the second premolar (34.3%). The mean horizontal dimension of the MF was 3.1 mm, the vertical dimension was 2.8 mm, and the mean vertical distance from the alveolar crest was 14.2 mm. An AMF was observed in 12.8% of cases with a mean distance of 4.1 mm from the MF. An AL was present in 47.2% of cases with a mean loop length of 3.38 mm. An LLF was present in 20.4% of cases, predominantly below the first premolar (27.3%) with a mean angle of entry of 148°. The LLC always communicated with the MC and generally not with the tooth apex. A statistically significant association existed between the presence of the LLF and AMF. ConclusionsThe anatomic complexity of the MF region was confirmed; hence, CBCT-based evaluation is essential before surgical exploration of this region.

Diffusion of Two Botulinum Toxins Type A on the Forehead: Double-Blinded, Randomized, Controlled Study

Different diffusion of different botulinum toxin type A (BoNTA) preparations may account for differences in outcomes in cosmetic clinical practice. A double-blind, randomized, self-controlled study was performed to evaluate the diffusion characteristics of onabotulinumtoxinA and a Chinese type A botulinum toxin (CBTX-A). Healthy volunteers (N=20) were recruited to receive a 0.05-mL (2U) injection of BoTNA at four forehead sites (medial forehead (subcutaneous (SC)) and temporal forehead (intradermal (ID))). On day 14, the Minor's iodine starch test was performed and photographs were taken for calculating the area and dimensions of anhydrotic area. When BoNTAs were different, the anhidrosis ID area was significantly greater with CBTX-A than onabotulinumtoxinA, the vertical dimension was significantly longer with CBTX-A ID than onabotulinumtoxinA ID and the horizontal dimension was significantly greater with CBTX-A ID than onabotulinumtoxinA ID. The area of anhidrosis SC was significantly greater with CBTX-A than onabotulinumtoxinA. When injection depths were different, the mean horizontal dimension was significantly greater with onabotulinumtoxinA SC than ID. Comparing the dimension of the same BoNTA and injection method, the vertical dimension was significantly greater than the horizontal dimension. OnabotulinumtoxinA diffuses less than CBTX-A. ID injection technique may result in less diffusion than SC.

Size-frequency statistics of boulders on global surface of asteroid 25143 Itokawa

Abstract The surface of asteroid 25143 Itokawa is covered with numerous boulders although gravity is very small compared with that of other asteroids previously observed from spacecraft. Here we report the size-frequency statistics of boulders on the entire surface of Itokawa based on high-resolution images (1 pixel ≈0.4 m) obtained by the Hayabusa spacecraft. There are 373 boulders larger than 5 m in mean horizontal dimension on the entire surface—0.393 km2—and the number density is nearly 103/km2. The cumulative boulder size distribution on the entire surface has a power-index of −3.1 ± 0.1. For the east and west sides and the head and body portions of Itokawa, the power-index of the size distributions and the number densities of boulders of these areas are thought to be similar from the statistical point of view. A global mapping of boulders shows that there is no apparent correlation in the locations of boulders and craters. The ratio of the total volume of the boulders to the total excavated volume of the craters on Itokawa is ≈25% when only craters larger than 50 m in mean diameter are considered, and this ratio is extremely larger than that on Eros and the Moon, respectively. The origin of boulders on the surface of Itokawa was examined quantitatively by calculating the number of boulders and the size of the largest boulder using a model based on impact cratering experiments. The result indicated that the boulders on the surface of Itokawa cannot solely be the product of craters. Our results suggest that the boulders originated from the disruption of the larger parent body of Itokawa, as has been described in previous papers (Fujiwata et al., Science, 312, 1330–1334, 2006; Saito et al., Science, 312, 1341–1344, 2006).

Histologic study of patterns of cervical involvement in FIGO stage II endometrial carcinoma.

The pathology of cervical involvement in endometrial carcinoma has not been fully defined previously. We reviewed the histopathology of 66 hysterectomies of women with stage II endometrial carcinoma. Cervical spread was categorized as macroscopic or microscopic; stage IIA or IIB; direct spread, surface or lymphvascular metastasis; and size, number, and location. The cervical tumor was macroscopically identified in 15 (23%) women and microscopically identified in 51 (77%). Twenty-one patients (32%) were stage IIA and 45 (68%) stage IIB. The method of spread was direct spread in 28 patients, surface metastases in 27, lymphovascular in 3, both direct spread and surface metastases in 7 and both direct spread and lymphovascular in 1. The cervical tumor had a mean horizontal dimension of 3 mm and a median of 2 mm. There were multiple sites of cervical tumor in 31 (47%) patients and single in 35 (53%). The sites of spread, including cases with multiple sites, were the endocervix in 60 women (90%), transformation zone in 24 (37%), and ectocervix in 3 (5%). Most patients had minimal microscopic cervical tumor. Small examples of direct spread may be an artifact of definition depending on the histology of the isthmian-endocervical junction and many surface metastases appear to follow dilatation and curettage. In 7 of 66, 11%, however, the cervical tumor was greater than 5 mm depth of invasion and/or the result of lymphvascular metastasis. Survival studies are required to compare minimal stage II endometrial carcinoma patients and those with larger and/or lymphvascular derived cervical tumor. Patients with minimal stage II and stage I patients should also be compared.

Mandibular reconstruction with the Dacron urethane tray: A radiologic assessment of bone remodeling

A retrospective study was made of 22 consecutive patients who underwent mandibular reconstruction with a Dacron (Osteo-mesh, Xomed Inc, Jacksonville, FL) tray technique from September 1988 to April 1992. Free autogenous iliac bone, in the form of particulate cancellous chips and marrow, was densely packed into the Dacron tray, that was adapted to bridge the mandibular segmental defect. Sixteen cases underwent uneventful healing with the formation of a continuous bony bridge and union with the remaining mandible. The pattern of bone remodeling and rate of resorption in these cases were assessed by sequential panoramic radiographs taken up to 3 years postoperatively. The mean horizontal dimension of the mandibular defects was 75 mm and the mean vertical reconstructed height was 25 mm. When the grafted bone was radiographically of uniform density, it progressed into a mature trabecular pattern matching that of the normal mandible. However, when there were areas of radiolucency, most likely from inadequate condensation of the graft, such areas were not replaced by bone in the long term. The bony height at both ends and the middle of the reconstructed segment underwent reasonably even resorption and retained about 80% of the bony height over a 3-year period. The rate of resorption was highest in the first 6 months and stabilized at about 2 years. There were six failures, all showing significant irregular bony resorption prior to tray removal.