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Background Degenerative lumbar spinal stenosis (DLSS) is the most common spine disease in the elderly population. It is usually associated with lumbar spine joints/or ligaments degeneration. Machine learning technique is an exclusive method for handling big data analysis; however, the development of this method for spine pathology is rare. This study aims to detect the essential variables that predict the development of symptomatic DLSS using the random forest of machine learning (ML) algorithms technique. Methods A retrospective study with two groups of individuals. The first included 165 with symptomatic DLSS (sex ratio 80 M/85F), and the second included 180 individuals from the general population (sex ratio: 90 M/90F) without lumbar spinal stenosis symptoms. Lumbar spine measurements such as vertebral or spinal canal diameters from L1 to S1 were conducted on computerized tomography (CT) images. Demographic and health data of all the participants (e.g., body mass index and diabetes mellitus) were also recorded. Results The decision tree model of ML demonstrate that the anteroposterior diameter of the bony canal at L5 (males) and L4 (females) levels have the greatest stimulus for symptomatic DLSS (scores of 1 and 0.938). In addition, combination of these variables with other lumbar spine features is mandatory for developing the DLSS. Conclusions Our results indicate that combination of lumbar spine characteristics such as bony canal and vertebral body dimensions rather than the presence of a sole variable is highly associated with symptomatic DLSS onset.

As some researchers theorized that cervicogenic headache (CEH) might be related to bony and discal features of the cervical spine, this retrospective study examined the shapes of the cervical vertebrae and intervertebral discs (IVDs) of individuals with CEH and compared them to asymptomatic controls. Scans of 40 subjects in their late 20’s–mid 30’s affected with CEH and 40 asymptomatic controls were obtained (overall = 19,040 measurements, age-sex matched, 20 males and 20 females in each group). The following cervical spine variables were measured: Supine lordosis, vertebral body-heights, A-P lengths, mediolateral widths and sagittal-wedging; IVDs heights and sagittal-wedging; pedicle heights, widths and transverse angles; laminar widths and transverse angles; articular facet angles, spinal canal, and transverse foramen lengths, widths, and areas. Both groups had similar shape variation along the cervical in all the measured parameters. There were no significant left–right differences in all measured parameters and no significant differences between the CEH and control groups concerning sex and age. Cervical IVDs were lordotic in shape, whereas their adjacent vertebral bodies were kyphotic in shape except for C2. In conclusion, the shape of the cervical spine and IVDs in subjects in their late 20’s–mid 30’s affected with CEH is identical to asymptomatic controls.

The aim of this study is to determine the sagittal inclination of lumbar spinous processes (SPs) in individuals with degenerative lumbar spinal stenosis (DLSS). It is a retrospective computerized tomography (CT) study including 345 individuals divided into two groups: control (90 males, 90 females) and stenosis (80 males and 85 females. The SP inclination was measured in the midsagittal plane from L1 to L5 levels. Stenosis males (L3-L5) and females (L1, L4) manifested significantly greater SP inclination compared to their counterparts in the control group. Males had significantly horizontal SP orientation compared to females (L1, L2). We also found that SP inclination became steeper as we descend caudally. This study indicates that SP inclinations are significantly associated with DLSS.

The aim of the current study was to establish whether the vertebral morphometry (e.g., vertebral body width and spinal canal diameters) is associated with degenerative lumbar spinal stenosis (DLSS). A retrospective computerized tomography (CT) study from L1 to L5 for two sample populations was used. The first included 165 participants with symptomatic DLSS (sex ratio 80 M/85F), and the second had 180 individuals from the general population (sex ratio: 90 M/90F). Vertebral body length (VL) and width (VW) were significantly greater in the stenosis males and females compared to their counterparts in the control. The mean VL in the stenosis males was 31.3 mm at L1, 32.6 mm at L2, 34 mm at L3, 34.1 mm at L4, and 34.5 at L5 compared to 29.9 mm, 31.3 mm, 32.6 mm, 32.8 mm, and 32.9, respectively, in the control group ( P ≤ 0.003 ). Additionally, the bony anterior-posterior (AP) canal diameters and cross-sectional area (CSA) were significantly smaller in the stenosis group compared to the control. The mean AP canal values in the stenosis males were 17.8 mm at L1, 16.6 mm at L2, 15.4 mm at L3, 15.6 mm at L4, and 16.1 at L5 compared to 18.7, 17.8, 16.9, 17.6, and 18.8, respectively, in the control group. Vertebral length (OR-1.273 to 1.473; P ≤ 0.002 ), AP canal diameter (OR-0.474 to 0.664; P ≤ 0.007 ), and laminar inclination (OR-0.901 to 0.856; P ≤ 0.025 ) were significantly associated with DLSS. Our study revealed that vertebral morphometry has a role in DLSS development.

Processing-in-memory (PIM) using memristive technologies is an attractive solution for the memory wall problem. PIM can improve the performance and energy efficiency of computing systems by reducing the data transfer between the memory and the processor. Memristor Aided loGIC (MAGIC) is a popular memristive PIM technique that can perform any combinational logic as a sequence of atomic NOR/NOT operations. These NOR/NOT operations rely on initializing their output cell prior to computation. In this paper, we explore input overwriting: the use of the MAGIC gate output cell as an additional input without initializing it. We extend MAGIC and introduce X-MAGIC (eXtended MAGIC) which uses input overwriting, and demonstrate it by two gates, $A\cdot(\overline{B+C})$ and $A. \overline{B}$ , where $A$ is an overwritten input. We show that input overwriting improves functionality, performance, and effective lifetime of the system. Due to algorithmic difficulties, available PIM synthesis tools do not support input overwriting. We address these difficulties by modifying an existing synthesis tool for MAGIC (SIMPLER), and presenting several general principles and methods for supporting input overwriting. We examine two configurations of the modified synthesis tool using X-MAGIC gates, differing in their performance/area trade-off. Both configurations achieve a geomean improvement of over 16.5% in performance, and over 20% in effective lifetime compared to standard MAGIC. Due to algorithmic difficulties, available PIM synthesis tools do not support input overwriting. We address these difficulties by modifying an existing synthesis tool for MAGIC (SIMPLER), and presenting several general principles and methods for supporting input overwriting. We examine two configurations of the modified synthesis tool using X-MAGIC gates, differing in their performance/area trade-off. Both configurations achieve a geomean improvement of over 16.5% in performance, and over 20% in effective lifetime compared to standard MAGIC.

In-memory processing can dramatically improve the latency and energy consumption of computing systems by minimizing the data transfer between the memory and the processor. Efficient execution of processing operations within the memory is therefore, a highly motivated objective in modern computer architecture. This article presents a novel automatic framework for efficient implementation of arbitrary combinational logic functions within a memristive memory. Using tools from logic design, graph theory and compiler register allocation technology, we developed synthesis and in-memory mapping of logic execution in a single row (SIMPLER), a tool that optimizes the execution of in-memory logic operations in terms of throughput and area. Given a logical function, SIMPLER automatically generates a sequence of atomic memristor-aided logic (MAGIC) NOR operations and efficiently locates them within a single size-limited memory row, reusing cells to save area when needed. This approach fully exploits the parallelism offered by the MAGIC NOR gates. It allows multiple instances of the logic function to be performed concurrently, each compressed into a single row of the memory. This virtue makes SIMPLER an attractive candidate for designing in-memory single instruction, multiple data (SIMD) operations. Compared to the previous work (that optimizes latency rather than throughput for a single function), SIMPLER achieves an average throughput improvement of $435\times $ . When the previous tools are parallelized similarly to SIMPLER, SIMPLER achieves higher throughput of at least $5\times $ , with $23\times $ improvement in area and $20\times $ improvement in area efficiency. These improvements more than fully compensate for the increase (up to 17% on average) in latency.

The aim of this study is to establish whether facet tropism (FT) and orientation (FO) are associated with degenerative lumbar spinal stenosis (DLSS). A retrospective computerized tomography (CT) study including 274 individuals was divided into two groups: control (82 males and 81 females) and stenosis (59 males and 52 females). All participants have undergone high-resolution CT scan of the lumbar spine in the same position. FT and FO were measured at L1-2 to L5-S1. Significant sagittal FO was noted in the stenosis males (L2-3 to L4-5) and females (L2-3 to L5-S1) compared to the controls. The prevalence of FT was remarkably greater in the stenosis males (L4-5, L5-S1) and females (L3-4, L5-S1) compared to their counterparts in the control group. Our results also showed that FT (L3-4 to L5-S1) increases approximately 2.9 times the likelihood for DLSS development. This study indicates that FO and FT in the lower lumbar spine are significantly associated with DLSS.

The aim of this study was to compare pedicle dimensions in degenerative lumbar spinal stenosis (DLSS) with those in the general population. A retrospective computerized tomography (CT) study for lumbar vertebrae (L1 to L5) from two sample populations was used. The first included 165 participants with symptomatic DLSS (age range: 40-88 years, sex ratio: 80 M/85 F), and the second had 180 individuals from the general population (age range: 40-99 years, sex ratio: 90 M/90 F). Both males and females in the stenosis group manifested significantly greater pedicle width than the control group at all lumbar levels (P<0.05). In addition, pedicle heights for stenosis females were remarkably smaller on L4 and L5 levels compared to their counterparts in the control group (P<0.001). Males have larger pedicles than females for all lumbar levels (P<0.001). Age and BMI did not demonstrate significant association with pedicle dimensions. Our outcomes indicate that individuals with DLSS have larger pedicle widths than the control group. More so, pedicle dimensions are gender-dependent but independent of age and BMI.

The aim of this study was to reveal whether demographic aspect, vertebral morphometry, and spine degeneration are associated with lumbar Schmorl’s nodes (SNs). A retrospective cross-sectional study was performed using data from the Department of Radiology (Carmel, Medical Center, Israel) for 180 individuals: age range between 40 and 99 years; 90 males and 90 females. All participants had undergone high-resolution CT scans for abdominal diagnostic purposes in the same supine position prior to our study, which enabled the processing of the scans in all planes and allowed a 3D reconstruction of the lower lumbar region. Eighty individuals (44.4%) had at least one SN along the lumbar spine, particularly at L3-4 level (30%). Vertebral body length (L1 to L3) and width (L1 and L4) were significantly greater in the SNs group compared to non-SNs group. On contrast, disc height (L3-4 and L4-5) was significantly lesser in SNs group than non-SNs group. SNs was significantly associated with smoking (X2= 4.436, P=0.02) and degenerative lumbar spinal stenosis (X2= 5.197, P=0.038). Moreover, the prevalence of SN was significantly greater in individuals with vacuum phenomenon and osteophytes formation (L1-2 to L4-5 levels). This study indicates that vacuum phenomenon on L3-4 (OR: 4.7, P=0.034), smoking habit (OR: 3.2, P=0.003), disc height loss of L4-5 (OR: 0.798, P=0.008), vertebral body length of L1 (OR: 1.37, P

Earliest modern humans out of AfricaRecent paleoanthropological studies have suggested that modern humans migrated from Africa as early as the beginning of the Late Pleistocene, 120,000 years ago. Hershkovitzet al.now suggest that early modern humans were already present outside of Africa more than 55,000 years earlier (see the Perspective by Stringer and Galway-Witham). During excavations of sediments at Mount Carmel, Israel, they found a fossil of a mouth part, a left hemimaxilla, with almost complete dentition.The sediments contain a series of well-defined hearths and a rich stone-based industry, as well as abundant animal remains. Analysis of the human remains, and dating of the site and the fossil itself, indicate a likely age of at least 177,000 years for the fossil—making it the oldest member of theHomo sapiensclade found outside Africa.Science, this issue p.456; see also p.389

Due to high specificity and sensitivity noncontrast computerized tomography is increasingly used to diagnose and follow patients with ureteral stones. We evaluated the feasibility of limited field noncontrast computerized tomography to follow patients with ureteral stones.Included in the study were 71 patients who underwent diagnostic and followup noncontrast computerized tomography due to ureteral stones. According to stone position on the first diagnostic scan a limited field batch from the followup scan was formed and examined by an independent radiologist. Radiation doses and rates of potentially missed findings in the batch were compared to those of the full followup noncontrast scan.Average full followup noncontrast computerized tomography length was 46.5 cm and average batch length was 20.7 and 13.8 cm for proximal and distal stones, respectively. The average full followup noncontrast scan radiation dose was 12.2 mSv. Average batch doses were 6.1 and 4.1 mSv for proximal and distal stones, respectively (p = 0.002), resulting in a radiation exposure reduction of 48.8% for proximal stones and 66% for distal stones. In 3 cases additional clinical information (not including hydronephrosis) was missed when relying only on batch images. This additional information did not impact further urological treatment.Limited field noncontrast computerized tomography is a feasible option for following patients diagnosed with ureteral stones. It may lead to significantly lower radiation exposure.

A descriptive CT study of lumbar facet joint (FJ) arthrosis in general and spinal stenosis populations.To reveal the prevalence of FJ arthrosis in general and stenosis populations and to establish its relationship to age and sex.FJ arthrosis is a common radiographic finding and has been suggested as a cause of low back and lower extremity pain. It is also considered a dominant player in the genesis of lumbar spinal stenosis. Although it is well accepted that FJ arthrosis is an age dependent phenomenon, controversies still exist as to its association with sex and its prevalence at different spine levels. In addition, data on FJ arthrosis frequency in spinal stenosis population are missing.Two groups were studied. The first included 65 individuals with LSS (mean age = 66 ± 10 yr) and the second, 150 individuals (mean age = 52 ± 19 yr) without LSS related symptoms. Both left and right FJ arthrosis for each vertebral level (L3-S1) were evaluated on CT images (Brilliance 64, Philips Medical System, Cleveland, OH). Chi-square, Linear-by-Linear Association and McNemar test were carried out to reveal the correlation between FJ arthrosis and demographic factors (age, sex) and prevalence at different lumbar levels in both stenosis and nonstenosis groups. In addition, a two-way analysis of variance (ANOVA) was used to determine the association between body mass index (BMI) and FJ arthrosis.The rate of FJ arthrosis at L3-L4 and L4-L5 were significantly higher (P0.001) in the stenotic group compared to the control. In the control group the prevalence of FJ arthrosis increases cephalocaudally (L3-L4 = 16%, L4-L5 = 28%, L5-S1 = 55%), whereas in the stenotic group there is a sharp increase from L3-L4 (27%) to L4-L5 (58%), but not from L4-L5 to L5-S1 (55%). No association between FJ arthrosis and sex was noted. Although, mean BMI was significantly smaller in the control group compared to the stenotic group, no association between BMI and facet arthrosis was found. In the general population the prevalence of FJ arthrosis at all three levels was greater for the right side; however, significant difference (P = 0.004) was obtained only for L3-L4. In all joints studied, the prevalence of FJ arthrosis increases considerably from the young age cohort (18-39) to the old age cohort (60). Nevertheless, 10% of the young individuals (18-39) have already manifested FJ arthrosis at L5-S1. No arthrosis at that age was observed at L3-L4.FJ arthrosis is an age-dependent and BMI and sex independent phenomenon. In the general population, the prevalence of FJ arthrosis increases cephalocaudally with the highest frequency at L5-S1. In the stenotic group, the highest frequency was observed at the two caudal levels; L4-L5 and L5-S1. The prevalence of FJ arthrosis was greater for the right side.

STUDY DESIGN A descriptive computed tomography (CT) study of the ligamentum flavum (LF) thickness in individuals with normal and stenotic lumbar spines. OBJECTIVE To establish standards for normal and pathologic range of LF thickness and its asymmetry as indicated in CT images and to examine its association with vertebral body size, age, and gender. SUMMARY OF BACKGROUND DATA LF lines a considerable part of the posterior and lateral walls of the spinal canal and is a major role contributor to spinal canal stenosis. Due to methodologic deficiencies (e.g., small sample size, lack of control for vertebral body size, gender, and age), the normal range of LF thickness is still controversial. Furthermore, data on important aspect of LF thickness such as left-right differences are missing. METHODS Two groups of individuals were studied. The first group included 65 individuals with lumbar spinal stenosis (LSS) (mean age: 66 +/- 9.7 years) and the second, 150 individuals (mean age: 52 +/- 19 years) without LSS-related symptoms. LF thickness was measured on CT images (Philips Brilliance 64), obtained from axial plane scan at the intervertebral disc level. Measurements were performed at the levels of L3-L4, L4-L5, and L5-S1. Analysis of variance and t test were carried out to evaluate the association between LF thickness and demographic factors. RESULTS Absolute and relative LF thickness were significantly greater in the LSS group at the levels of L3-L4 and L4-L5 on both sides, compared to control group (P < 0.05). LF thickness was independent of gender (absolute and relative thickness). Even though LF thickness at all levels significantly increases with age, significant changes after the age of 60 occurred only at L3-L4. Significant asymmetry in LF thickness was found at L3-L4 (2.9 +/- 0.90 mm on the right vs. 2.76 +/- 0.90 mm on the left) and L5-S1 (3.42 +/- 1.1 mm on the right vs. 3.22 +/- 1.22 mm on the left) (P < 0.05). CONCLUSION LF thickness is an age-dependent and gender-independent phenomenon. LF is significantly thicker on the right side. The borderline between normal and pathologic LF thickness should not be set at 4 mm.

Smaller kidney lesions which are more often detected recently by accidental imaging are amenable for nephron sparing approach whether at open surgery, laparoscopy or ablative techniques. The pretreatment planning is based on multiplanner CT expected to well define the relationship of the lesion to the major renal blood vessels and collecting system (CS). This study is aimed to compare the pre-surgical CT measurements of the distance from tumor to CS to the actual distances observed on radical nephrectomy specimens. Contrast CT of 39 patients with renal cell carcinoma (RCC) underwent measurements of the distance between CS and renal tumor. All measurements were confronted with the measurements performed on radical nephrectomy specimens of the same patients. Of all 39 patients in 34 (87%) CT showed a contact relation between the tumor and the CS. In fact, the CS involvement has been histologically proven only in three (7.6%) cases. Cutting off the measurements at thresholds of 2 and 5 mm also showed a significant discrepancy between CT and specimen measurements. The trend of NSS and ablative techniques stressed out the importance of pretreatment measurements of the distance between the tumor and the CS. This study as performed on radical nephrectomy specimens points out the overestimated proximity of the tumor to the CS. These data if confirmed by other studies, may play a role while planning the management of NS approaches.

To assess retrospectively the incidence, clinical features, and treatment of colonic perforation at computed tomographic (CT) colonography in a large multicenter cohort.The study was performed in accordance with the institutional ethics committees' requirements of a retrospective review in each of the participating centers, and no informed consent was required. A review of all patients who underwent CT colonography between January 2001 and December 2004 in 11 medical centers representing more than 95% of studies performed in a single country was performed to determine the rate of colorectal perforation. Data about patient demographics and patient- and procedure-related risk were recorded. Information about the location of the perforation, its likely mechanism, and treatment was collected. Analysis included calculation of rates of colonic perforation and surgical treatment and of 95% confidence intervals.A total of 11 870 CT colonographic studies were performed in 6837 (57.6%) men and 5033 (42.4%) women (mean age, 59.9 years; range, 38-90 years) with seven cases of colorectal perforation, yielding a risk rate of 0.059% (one of 1696 studies; 95% confidence interval: one of 974, 971 of 6537). The mean age of the patients with perforation was 77.8 years. Six (84%) of seven cases of perforation occurred in symptomatic patients at high risk for colorectal neoplasia, and one (16%) occurred in an asymptomatic average-risk patient. All studies were performed after insufflation of room air. Six (84%) cases of perforation occurred in patients in whom a rectal tube was inserted, and in five of them, a balloon was inflated. Five (71%) cases of perforation occurred in the sigmoid colon; and two (29%), in the rectum. Four (57%) patients (one in 2968 patients; 95% confidence interval: 1.5 in 10 000, 14.7 in 10 000) required surgical treatment. Possible factors that contributed to perforation were left inguinal hernia containing colon (n = 4), severe diverticulosis (n = 3), and obstructive carcinoma (n = 1).Perforation of the colon and rectum is a rare complication of CT colonography. Older age and underlying concomitant colonic disease were present in patients with perforation.

Although hyperostosis frontalis interna (HFI) has been documented in the medical literature for over 300 years, its etiology remains undetermined. It is generally assumed to be associated with hormonal disturbances of the gonads. The aim of this study was to examine the association between androgen deprivation and development of HFI in males. Two groups of males over 60-years old were compared: a control group that included 180 healthy males, 45 suffering from benign prostatic hypertrophy (BPH) and a study group of 127 males with prostate cancer: 67 who received complete androgen block treatment, and 60 who received different treatments or none at all. CT head scans were used to identify and classify HFI (Brilliance 64, Philips Medical Systems, slice thickness 3 mm x 1.5 mm). It was found that males who received a complete androgen block manifested significantly higher prevalence of HFI compared to healthy males. However, no significant difference in HFI prevalence was found between males suffering from BPH and healthy males or males with prostate cancer who had not received a complete androgen block. A positive association between length of hormonal treatment and manifestation of HFI was shown. It can be concluded that BPH does not promote development of HFI; males who are hormonally treated for prostate cancer are at a higher risk of developing HFI compared to healthy males; the longer the duration of hormonal treatment, the higher the risk of developing HFI.

Although Schmorl’s nodes (SNs) are a common phenomenon in the normal adult population, their prevalence is controversial and etiology still debatable. The objective was to establish the spatial distribution of SNs along the spine in order to reveal its pathophysiology. In this study, we examined 240 human skeleton spines (T4-L5) (from the Hamann–Todd Osteological Collection) for the presence and location of SNs. To determine the exact position of SNs, each vertebral body surface was divided into 13 zones and 3 areas (anterior, middle, posterior). Our results show that SNs appeared more frequently in the T7-L1 region. The total number of SNs found in our sample was 511: 193 (37.7%) were located on the superior surface and 318 (62.3%) on the inferior surface of the vertebral body. SNs were more commonly found in the middle part of the vertebral body (63.7%). No association was found between the SNs location along the spine and gender, ethnicity and age. This study suggests that the frequency distribution of SNs varies with vertebra location and surface. The results do not lend support to the traumatic or disease explanation of the phenomenon. SNs occurrences are probably associated with the vertebra development process during early life, the nucleus pulposus pressing the weakest part of the end plate in addition to the various strains on the vertebrae and the intervertebral disc along the spine during spinal movements (especially torsional movements).

The present paper examines gender differences and changes in prevalence of ankylosed sacroiliac joint (SIJ) with age. SIJs of 287 patients (159 males and 128 females), aged 22-93 years, were examined for fusion, using 3-D CT images. Presence, side and location of the fusion along the joint borders were recorded. Fusion of the SIJ was found to be gender and age dependent; present in 27.7% of all males in contrast to only 3.0% in females (p0.001). The phenomenon increased with age in the male population from 5.8% in the 20-39 age cohorts to 46.7% in the 80+ cohort. As mobilization and/or manipulation of a dysfunctional SIJ are common procedures used by manual therapists, the effect that aging has on SIJ mobility requires therapists to alter or change their method with advancing age.

A case of congenital urethral polyp in a 10-month-old boy is presented. These rare congenital tumors can lead to urinary retention, hematuria, urinary tract infections, hydronephrosis and hydroureter. Traditionally the diagnosis was based either on voiding cystourethrography or cystoscopy. The sonographic features of these polyps have only been reported in a few cases in the past. This modality is not infrequently the imaging procedure of choice in the work-up of children with signs and symptoms related to the urinary system. In the case presented herein the polyp was demonstrated initially by sonography as a soft tissue mass arising at the base of the urinary bladder. The differential diagnosis of these lesions is presented.