Drainage Patterns Research Articles

Exploring the Geomorphological Nature and its Consequences in Agaie & Lapai L Gas of Niger State and Environment Using GIS & LandSat-8 Imagery

The activities of geomorphology has persisted over many years in the study area un-noticed, un-checked or controlled and un-abaited. That is why, this article is poised to evaluate the morphological consequences on the study area topography, particularly settlements and farm-land areas along the fringes of the river (coast) and suggest way-out. In order to assess the magnitude of morphological changes over-time, the of Geographic Information System (GIS), Remote Sensing (RS) techniques (that is, using LandSat Imagery-8) and Shuttle Radar Thematic Mapper (SRTM) were deployed and survey method (via a structured questionnaire) to extrapolate the socio-economic consequences on the inhabitants of the study area. The GIS, RS and SRTM revealed the morphological changes and its evolution such as the drainage pattern, topography (that is, relief), flooding and flood plains. It is expected that, policy makers, water resources engineers and environmental managers would find the out-come of this investigation use for planning and making informed decision to avert future environmental hazards of different types.

Assessment of post-pyeloplasty renal drainage in antenatally detected hydronephrosis by 99mTc-L, L-Ethylenedicysteine renal scintigraphy: the importance of delayed imaging.

Diuretic renal scintigraphy is important in diagnosing pelvi-ureteric junction obstruction (PUJO) in antenatally detected hydronephrotic (ANH) kidneys. Early-phase dynamic renal scintigraphy has several pitfalls contributing to the false interpretation of obstructed drainage, especially after pyeloplasty. This study explores the utility of delayed imaging in 99mTc-L,L-Ethylenedicysteine (EC) diuretic renal scintigraphy to assess post-pyeloplasty renal drainage in ANH. Data from May 2019 to January 2024 was retrospectively studied to identify infants with ANH who underwent surgery for PUJO and pre-and post-surgical assessment of renal drainage using 99mTc-L,L-EC diuretic renal scintigraphy. Dynamic and post-void static images were analyzed to calculate percentage drainage till 3h. Pre- and post-operative quantitative parameters were compared. Receiver operator curve analysis was done to calculate the threshold drainage to detect renal obstruction on postvoid images. In a cohort of 104 patients with a mean age of 10.1 ± 6.5months (range 2-36months) at surgery, 106 renal units (bilateral involvement in two patients) were analyzed. There was no significant difference in the sum of obstructive and equivocal curve patterns (105 vs 79, p = 0.06) and T1/2 values (105 vs 82, p = 0.093) before and after surgery. However, there was a significant difference between the pre-and post-surgery median 3-h percentage drainage (26 vs 80%, p < 0.001). A drainage threshold of less than 59% at 3h had 93.4% sensitivity and 92.5% specificity to detect obstructive drainage. Delayed images in diuretic renal scintigraphy are crucial in accurately interpreting post-pyeloplasty drainage patterns and help overcome pitfalls of the dynamic study.

Anomalous venous collaterals in Apert and Crouzon syndromes and their relationship to ventricle size and increased intracranial pressure.

The exact association between the frequently present anomalous intracranial venous vasculature, emissary collaterals, ventriculomegaly, and increased intracranial pressure (ICP) in children with Apert and Crouzon syndromes remains an enigma. This study aimed to evaluate the association between the aberrant venous system and ventricle size and increased ICP, and to assess the development of the venous structures over time. This retrospective cohort study included all patients with Apert or Crouzon syndrome with available CT venography (CTV) scans of the brain. Anomalous venous vasculature was assessed by the total collateral score (TCS), which scored 9 intra- and extracranial venous structures (TCS range 0-16). Ventricle size (fronto-occipital horn ratio [FOHR]) was measured on the same scan. The presence of increased ICP, a shunt, tonsillar herniation, and head circumference were extracted from electronic patient records and were used as secondary covariates. Subsequent CTV scans were scored when available. Ninety patients were included in this study. The mean TCS was 7.5 ± 2.5, and was comparable for patients with Apert and Crouzon syndromes (mean 8.0 and 7.3, respectively). The presence of an extra abnormal venous structure was associated with an increase of the FOHR of 3.2% (p < 0.01). After dividing the venous structures into intra- and extracranial, a similar association between both and the FOHR was found (4.1% and 2.3%, respectively; p < 0.01). The TCS was similar for patients with normal and increased ICP at the time of the scan. Sixteen patients had dual CTV scans. The median time between both scans was 3.2 years. The presence of collaterals remained stable over time (median ΔTCS = 0.3). Seven patients with functioning shunts also maintained high TCSs (median TCS = 9). In patients with Apert and Crouzon syndromes, a close relationship between venous collaterals and ventricle size was observed, in which a more extensive aberrant venous drainage pattern, both intra- and extracranial, was associated with larger ventricles. Preliminary longitudinal data suggested that the presence of venous collaterals remained constant over time despite effective treatment of increased ICP, indicating reliance on these collaterals even in cases of normal ICP. The authors hypothesize that this dependence on collateral drainage is the result of their aberrant internal venous anatomy and predisposes individuals to increased ICP.

A Cadaveric Study of Variations in Lung Fissures and Drainage Patterns of Pulmonary Veins at the Hilum With Its Clinical Implications

A Cadaveric Study of Variations in Lung Fissures and Drainage Patterns of Pulmonary Veins at the Hilum With Its Clinical Implications

Lymphatic mapping in second primary or recurrent oral cavity cancer with prior neck treatment: A case series and scoping review

ObjectivesLymphatic mapping is an established technique to map drainage patterns in oral cancer. Its utility in patients who have undergone prior radiation or neck dissection is not well studied. MethodsPatients presenting to a single tertiary cancer center between 2021–2023 for a recurrent/second oral cancer that underwent lymphatic mapping were considered. All patients had a history of a head and neck cancer treated with either radiation or neck dissection. We further conducted a scoping review in MEDLINE, Embase, and Web of Science of lymphatic mapping in oral cancer patients with previous neck treatment. ResultsIn our single center review, a total of 11 patients were included. 73 % received prior radiotherapy and 55 % underwent prior neck dissections for a head and neck cancer. Lymphoscintigraphy-directed neck dissections identified sentinel nodes in 9/11 patients, with only one patient who had positive sentinel node disease. There were no reports of regional recurrence at a median of 10 months follow-up. Our scoping review of 980 studies identified 151 additional patients who underwent sentinel node biopsy for a second oral cancer after previous neck treatment. Overall, the negative predictive value of lymphatic mapping in all studies was 96.7 %. ConclusionLymphatic mapping is feasible in secondary or recurrent oral cavity cancers even in patients with prior radiation or surgical management of the neck. The literature to date demonstrates a negative predictive value of ∼ 97 % for sentinel node mapping and warrants further consideration in the management of salvage oral cancer.

Integrated Morphometric and Hypsometric Analysis of Niragantipalli Micro Watershed Using Remote Sensing and Geographical Information System Techniques

Employing Remote sensing (RS) and geographic information system (GIS) for the morphometric parameters analysis are discovered to be tremendous usefulness in the prioritization of watersheds for soil, water conservation and natural resource management at micro watershed level. The analysis of morphometric parameters plays a crucial role for understanding and managing watersheds. In current study an, attempt was to determine the morphological parameters of Niragantipalli micro-watershed in Chikkaballapura District of Karnataka, India. For detail study, Google earth pro, GPS visualizer conversion toll and Arc GIS were used for preparation of DEM and delineation of the watershed boundary. GIS was used for evaluation of basic, linear, areal and relief aspects of morphometric parameters. The Niragantipalli micro-watershed occupies an area of 632 ha with third order stream (truck order) and dendritic drainage pattern. The mean bifurcation ratio of the micro-watershed is 2.5 it suggests that the drainage system formed on homogeneous rock when the influences of geologic structures on the network of streams were negligible and generate sharp peak flow. With a drainage density of 1.31 km/km2, the drainage network is extremely coarse. The watershed is elongated, as shown by the form factor of 0.27 and elongation ratio of 0.58. The results from the morphometric analysis of the watershed are very beneficial for developing and designing conservation structures of soil and watershed management measures. The hypsometric curves’ structure as well as estimated hypsometric integral results reflects the Niragantipalli Micro Watershed erosional stages. As a result, the study concludes that morphometric and hypsometric analysis findings may be useful to stakeholders participating in catchment development and management projects.

Sinus vein thrombosis conundrum: Persistent empty sella vs. flexible optic nerve sheath

IntroductionOur objective was to investigate the potential effect of thrombotic burden on pituitary gland height, bony sella and optic sheath width, taking into consideration the various venous sites and dominant drainage pattern. Patients and MethodsThis retrospective cohort study followed patients diagnosed with cerebral sinus vein thrombosis in a single primary healthcare center between the years 2000 and 2022. Data was collected from both CT/V and MR/V scans available on the local PACS system. Dural sinuses were divided into main anatomical sites and scored for patent, partially or totally blocked lumen. Dominant drainage flow was noted for each patient. For most scans, pituitary mid height, maximal depth and AP width of the bony sella and dorsum sella to tuberculum sella distance were assessed. Optic sheath width was measured for both sides at the maximal retrobulbar diameter. Regression methods, including linear mixed models, and non-parametric tests were used to analyze the data. Results90 patients (mean age, 44 years ±16.8, 54 women) were evaluated. Overall thrombus burden did not correlate with pituitary mid-height, however a relationship was observed between the change (from presentation) in the superficial thrombus score and the average width of the optic nerve sheath; the width of the optic sheath tended to decrease as thrombus burden improved and vice versa (p = 0.010). ConclusionsThrombus recanalization had a favorable effect on the optic nerve sheath diameter but did not appear to reverse the flattening of the pituitary gland, regardless of temporal improvement.

Classification, angioarchitecture and treatment outcomes of medullary bridging vein-draining dural arteriovenous fistulas in the foramen magnum region: a multicenter study.

This study aimed to classify medullary bridging vein-draining dural arteriovenous fistulas (MBV-DAVFs) located around the foramen magnum (FM) according to their location and characterize their angioarchitecture and treatment outcomes. Patients with MBV-DAVFs diagnosed between January 2013 and October 2022 were included. MBV-DAVFs were classified into four groups. Jugular vein-bridging vein (JV-BV) DAVF: located in proximity to jugular fossa, Anterior condylar vein (ACV)-BV DAVF: proximity to anterior condylar canal, Marginal sinus (MS)-BV DAVF: lateral surface of FM and Suboccipital cavernous sinus (SCS)-BV DAVF: proximity to dural penetration of vertebral artery. Twenty patients were included, three JV-BV, four ACV-BV, three MS-BV and ten SCS-BV DAVFs, respectively. All groups showed male predominance. There were significant differences in main feeders between JV (jugular branch of ascending pharyngeal artery) and SCS group (C1 dural branch). Pial feeders from anterior spinal artery (ASA) or lateral spinal artery (LSA) were visualized in four SCS and one MS group. Drainage pattern did not differ between groups. Transarterial embolization (TAE) was performed in three, two, one and two cases and complete obliteration was obtained in 100%, 50%, 100% and 0% in JV, ACS, MS and SCS group, respectively. Successful interventions without major complications were finally obtained in 100%, 75%, 100%, and 40% in JV, ACS, MS and SCS group, respectively. JV-BV DAVFs were successfully treated using TAE alone. SCS-BV DAVFs were mainly fed by small C1 dural branches of vertebral artery often with pial feeders from ASA or LSA, and difficultly treated by TAE alone.

Widefield indocyanine green angiography evaluating choroidal vein drainage pattern and choroidal vein alterations in acute and chronic central serous chorioretinopathy

PurposeTo access the distribution of choroidal vein drainage pattern and the choroidal vein alterations in choroidal vascular hyperpermeability (CVH) areas in eyes with acute and chronic central serous chorioretinopathy (CSC) using widefield indocyanine green angiography (WF-ICGA). MethodsIn this retrospective observational study, medical records and multimodal imaging of 127 patients (165 eyes) with CSC were reviewed. The number and location of dominant vortex veins and CVH areas on WF-ICGA images were evaluated. Choroidal vein alterations, including fusiform, bulbosity, sausaging, choroidal vein confluence and intervortex venous anastomosis, were identified in CVH areas. The differences of choroidal features were compared between acute and chronic groups. ResultsSixty-three acute CSC eyes and 102 chronic CSC eyes were evaluated. In this study, 125 eyes (75.76 %) exhibited an asymmetric pattern of choroidal vein drainage routes. Chronic CSC group had more CVH areas compared with acute CSC eyes in general (P < 0.001). Compared with chronic CSC eyes, CVH areas in acute CSC eyes were more likely to occur in the dominant vortex vein system (P = 0.006). Regarding the choroidal vein alterations, all kinds of anatomical changes were significantly more pronounced in chronic CSC eyes compared with acute group (P < 0.001 for all), with sausaging and intervortex venous anastomosis more commonly observed in chronic group (P < 0.001 and P = 0.002, respectively). The best corrected visual acuity (BCVA) of chronic symmetric CSC was significantly better than that of chronic asymmetric CSC cases (P = 0.006), with the BCVA showing a correlation with the frequency of sausaging dilations (P = 0.032). An increased number of sausaging dilation was associated with poorer visual acuity in chronic asymmetric CSC. ConclusionsChoroidal vascular remodeling occurs throughout the entire course of the CSC, with the formation of intervortex venous anastomosis creating a new drainage path that helps ameliorate choroidal vein congestion over time.

Aeromagnetic data reveals buried Quaternary drainage patterns in the Gulf of St Lawrence (Canada)

Short-wavelength, low-amplitude magnetic anomalies form dendritic patterns on the shallow water (&lt;100 m depth) Magdalen Plateau in the Gulf of St Lawrence, Canada. High-resolution seismic data indicate that these magnetic anomalies are associated with 0.6–2 km wide incised Quaternary valleys with relatively flat bottoms lying 30–70 m below the seafloor. The magnetic signature of the valleys is due to high magnetic susceptibility volcanic detritus derived from the erosion of the volcanic rocks that overlie most of the salt bodies in this area. This study shows that magnetic data may be a useful tool for mapping surficial sediments. These magnetic data provide the first offshore evidence for the direction of major water discharge. It remains unclear whether the valleys were formed by river incision during one or several regional lowstand(s) or from one or several sub-glacial discharge episode(s) across the Magdalen Plateau. The valley evidence should be incorporated into any future palaeogeographical reconstructions.

Prophylactic intra-abdominal drainage during pancreaticoduodenectomy: A systematic review and meta-analysis

Background: Prophylactic abdominal drainage during pancreaticoduodenectomy (PD) is a common treatment strategy for pancreatic fistula. However, its benefits and safety have been the subject of debate. The objective of this meta-analysis and system review is to assess the effects of prophylactic drainage, various types of drainage (active and passive), and the timing of drainage removal (early and late) on the postoperative outcomes of PD. Methods: A systematic literature search was conducted in the PubMed, Web of Science, and Cochrane Library databases as of April 28, 2024. Randomized controlled trials (RCTs) comparing prophylactic abdominal drainage, different drainage patterns, and the timing of drainage removal after PD were included, and the postoperative outcomes were evaluated. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated to aggregate dichotomous outcomes. Meta-analysis was performed using the Mantel-Haenszel fixed- and random-effects models. Results: Nine RCTs, including a total of 1638 patients, were incorporated in our study. The meta-analysis showed no statistically significant differences in postoperative outcomes between the closed-suction drain (CSD) group and the passive drain to gravity (PDG) group. Compared to the late drain removal (LDR) group, the early drain removal (EDR) group had a significant reduction in the incidence of Clinically relevant postoperative pancreatic fistula (CR-POPF) (OR=0.39, 95% CI=0.20 to 0.79; P=0.009), morbidity (OR=0.41, 95% CI=0.20 to 0.84; P=0.01) and intra-abdominal infection (OR=0.40, 95% CI=0.22 to 0.75; P=0.004). For the group of present of drainage and the group of absent of drainage, the patient inclusion criteria of the included studies were too heterogeneous, making meta-analysis inappropriate. Conclusion: The existing evidence is insufficient to negate the necessity of prophylactic drainage after PD. The meta-analysis did not show superiority of any specific approaches of drainage tube. But this review did indicate that patients benefit from EDR in terms of CR-POPF, morbidity and intra-abdominal infection. EDR was recommended for low/intermediate risk patients.

Thousands of shallow, relict gullies indicate thermo-erosion on the sandy uplands of northern Lower Michigan during the Late Pleistocene

We build on previous work which explained the origin of myriad gullies and incised channels on the dry, sandy uplands of northern Lower Michigan by invoking widespread permafrost. Indicators of permafrost (ice-wedge casts and patterned ground) are known from many sites across the region. Our study area, within an extensive reentrant of the retreating Laurentide Ice Sheet, had been particularly well positioned, geographically, for permafrost. Our goal was to characterize the geomorphic characteristics of the gullies on 72 large ridges, to address the hypothesis that they had formed in association with permafrost. Across the study area, thousands of dry, narrow channels and gullies occur in dense networks, typically with channels aligned directly downslope, in parallel drainage patterns. Most of the gullies exhibit only a minimal amount of incision (ca. 2–3 m), a nearly straight longitudinal profile, and lack a clear depositional fan at their mouth. Even where small fans are present, they are subtle and exhibit little down-fan textural sorting, as would be present in larger, more mature fluvial systems. Gully morphologies did not exhibit strong morphological differences as a function of aspect, as we would have expected for an erosional, periglacial system forming on fairly steep slopes. Nonetheless, in these sandy/gravelly sediments, we could find no other scenario that would have allowed for runoff and gully formation, except ice-rich permafrost that limited infiltration and promoted saturation of the active layer, and eventually, runoff. We conclude that the gullies formed via thermo-erosion into ice-rich permafrost, involving mostly fluvial processes but also some slope failure. Even though thermo-erosion can rapidly form deep gullies, our study area has mainly weak gully forms, perhaps because: (1) permafrost existed here only briefly, (2) the landscape was so cold and the permafrost so ice-rich that runoff was rare, (3) the permafrost on the sandy slopes remained somewhat permeable, limiting runoff, and/or (4) the paleoclimate was so dry that little water was available for sediment transport. We could find no evidence that the gullies developed within preexisting polygonal networks, as is happening today in polar regions under a warming climate. Thus, our study has implications for areas of the Arctic and Antarctic that are, today, experiencing rapid hydrological changes.

Morphometric analysis and LULC change dynamics of Nayar watershed for the sustainable watershed management

The morphometric analysis of the watersheds is essential for the conservation of natural resources, including soil, water, and vegetation. The Morphometric analysis defines the linear, areal and relief aspects of the watershed. It involves the comprehensive analysis of various factors such as drainage network, surface water flow, and other topographical features. The aim of this study is to develop a sustainable watershed management strategy for the Nayar watershed based on morphometry and Land Use Land Cover (LULC) change dynamics. The Nayar watershed has a total area of 1956.33 km2. The multispectral satellite imagery, Digital Elevation Model (DEM) data, and Survey of India (SOI) Toposheets were used for understanding the topographical and morphological characteristics along with the LULC change dynamics. The findings of this research conclude that the Nayar watershed has parallel and dendritic drainage patterns with high relief. According to the LULC change dynamics, the Nayar watershed's area change comprising 57.60 km2 and 57.15 km2, are from Agricultural Land to Wasteland and from Forest Cover to Wasteland, respectively. This shift in the hilly region will increase the risks of landslides and erosion. Furthermore, the change of 110.03 km2 area of Forest Cover to Agricultural Land raises further challenges due to loss of natural vegetation in long run. In summary the change in LULC of Nayar watershed is vulnerable to risk of natural calamities like landslide, erosion. This work would be helpful to many experts and decision-makers for sustainable watershed management and natural resource management.

Morphological Analysis of River Characteristics in Musi Rawas Utara Regency

Effective watershed management requires the efficient collection, storage, and use of runoff water, as well as the recharge of groundwater. This study will employ morphometric analysis to determine the characteristics of the rivers flowing through one of the districts of the Province of South Sumatera, Musi Rawas Utara (Muratara). Using DEM data and GIS software, this study conducted a quantitative-descriptive analysis to obtain quantitative information about the watershed. The acquired numbers are interpreted descriptively to provide a description of the watershed's characteristics and their implications for rivers in Muratara.The eighth-order rivers of Muratara Regency are classified as major rivers. A mean bifurcation ratio (Rb) of 3.98 indicates that geological features have no effect on the typical flat drainage pattern. On average, the drainage density of the watersheds was moderate, but a few locations had a very high drainage density range, indicating their erodibility. The basins of rivers with low circularity and elongation ratios (0.19 and 0.48, respectively) are elongated and have a steep slope. The morphometric research reveals that the Muratara rivers have abundant water resources and are also predicted to experience numerous water-related disasters. Using morphometric knowledge, however, the local government could develop mitigation and planning systems for river management. Future measures must include ensuring that adequate drainage systems are in place and that all construction adheres to the principles of proper land management.

Research progress on the distribution patterns and surgical dissection of central lymph nodes in left-sided colon cancer

Lymphatic metastasis is one of the main pathways of colorectal cancer spread and also a crucial factor in patient long-term prognosis. Lymph node dissection in the possible tumor drainage area, particularly the central group of lymph nodes at the root of the tumor-associated supplying artery, is a key and challenging aspect of surgical techniques. Currently, the patterns of lymphatic drainage and the distribution of central lymph nodes in left-sided colon cancer are not well illustrated, and there is no consensus on the necessity and extent of central lymph node dissection. This has led to significant variability in the extent of lymph node dissection among different surgeons in clinical practice, a lack of quality control standards for surgical procedures, and impacts on postoperative treatment strategy and long-term outcomes. Moreover, current research on lymphatic drainage and metastasis is primarily based on traditional anatomy, whereas individualized, precise approaches to lymph node dissection have not been realized. The application of preoperative and intraoperative lymph node imaging techniques based on functional anatomy in colorectal cancer patients is still under exploration.

Catastrophic outburst floods along the middle Yarlung Tsangpo River: Responses to coupled fault and glacial activity on the Southern Tibetan Plateau

The immense outburst floods that have occurred on the Tibetan Plateau during the Late Quaternary are closely linked to tectonic and climatic factors. These floods likely induced very rapid, short-term geomorphic impacts on the evolution of mountain drainage systems and patterns of sedimentary movement. In this study, four glacially-dammed lake outburst flood events that occurred along the middle reaches of the Yarlung Tsangpo River since the Middle Pleistocene were reconstructed by combining comprehensive geomorphic, stratigraphic and geochronologic investigations. The most recent outburst flood sequence occurred at ∼10.5 ka, with a peak discharge of ∼5 × 105 m3/s. The tilted uplift of the Cona Normal Fault has resulted in localized topographic lift and the formation of river knickpoints, contributing to the development and stabilization of glacial dams. River damming and outburst events have also been influenced by glacial-interglacial climate fluctuations since the Middle Pleistocene. The focused erosion and extensive mobilization of sediment by these low-frequency, high-energy floods have resulted in a repeated pattern of material transport and deposition from the Tibetan Plateau interior to its exterior. Coupled with glacial activity, the primary factor impacting the sustained stability of knickpoints on the Yarlung Tsangpo River along the Tibetan plateau's southern margin has been differential rock uplift, which results in a distinct geomorphic pattern characterized by knickpoints, glacial dams and alternating wide valleys and deep gorges.

Traumatic middle meningeal arteriovenous fistulas (MMAVFs): an exploratory systematic review.

This study aims to systematically review case reports and case series in order to compare the postoperative course of conservative, endovascular and surgical treatments for traumatic dural arteriovenous fistulas predominantly supplied by the middle meningeal artery (MMAVFs), which usually occur following head trauma or iatrogenic causes. We conducted a comprehensive search of PubMed, Embase, Scopus, Web of Science, and Google Scholar until June 23rd, 2024. Three cohorts were defined based on the treatment modality employed. The primary outcomes were the rates of overall obliteration and postoperative complications, with all-cause mortlality considered as secondary outcome. A total of 61 studies encompassing 78 pooled MMAVFs were included in the qualitative analysis. The predominant demographic consisted of males (53.9%) with a median age of 50.5 (IQR: 33.5-67.5) years. The main etiologies for fistula formation were head trauma (75.6%), cranial neurosurgical procedures (11.5%) and endovascular embolization (8.97%). Venous drainage patterns were categorized as follows based on anatomical confluence: Class I (16.7%), II (14.1%), III (12.8%), IV (14.1%), V (7.7%), and VI (3.9%). Regarding treatment efficacy, the overall obliteration rate was 89.74%, achieved through endovascular (95.83%), surgical (64.29%) or conservative (93.75%) approaches. In terms of safety, the overall postoperative complication rate was 6.49% with an all-cause mortality rate of 8.97%, predominantly observed in the surgical group (35.71%). Our systematic review highlights the challenging management of traumatic MMAVFs, frequently associated with head injuries. Endovascular therapy has emerged as the predominant treatment modality, demonstrating markedly higher rates of fistula obliteration, reduced all-cause mortality, and fewer postoperative complications.

Morphometric indices assessment: Implications for active tectonics in the upper Narmada Basin, central India

During the Palaeoproterozoic era, the Northern and Southern cratonic blocks of the Indian Plate came together and amalgamated. Farther, facilitated by the East-West trending central Tectonic Suture Zone, characterized by the Son-Narmada Fault/Lineament (SNF/L) and Central Shear (CIS) Zone, has long intrigued researchers due to its implications for active tectonics, particularly in the Narmada basin. In this study, we employ geomorphic and morphotectonic indices to elucidate the neotectonic activity in the Upper Narmada basin (UNB) of central India. Utilizing SRTM-DEM data, we analyze morphometric and morphotectonic parameters to shed light on the development of drainage patterns and active tectonics within the basin. Our findings reveal a pronounced influence of tectonics on basin evolution, as evidenced by high bifurcation ratios indicative of intense tectonic activity and elevated ruggedness values suggestive of heightened erosion susceptibility. The predominant ENE-WSW orientation of the Son Narmada South Fault (SNSF) and Son Narmada North Fault (SNNF), aligned with major lineament trends, exerts control over the Narmada River drainage network. Additionally, the high value (<50) of the asymmetric factor reveals the significant tectonic influence on the Upper Narmada basin, while the transverse asymmetric factor and stream length index values further corroborate the basin's susceptibility to active tectonics. Notably, the abrupt elevation changes (200–600 m asl) reflected by Dhuandhar, Kapildhara and other falls along the course of Narmada provide compelling evidence of neotectonic activity. Thus, we assert that morphotectonic analyses employing Digital Elevation Maps, satellite imagery, and SRTM-DEM data represent an efficacious approach for investigating complex basin morphotectonics.

Managing Flow: Drainage and Flood Control in Eighteenth-Century London

The rapid expansion and urban development of eighteenth-century London altered existing drainage patterns and increased flood risk. The early modern sewer commissions, set up to deal with the status quo, struggled to cope with these changes. As the city expanded, a network of public and private drains and sewers was built up haphazardly over time, resulting in an exceedingly complex system that was difficult to manage and almost impossible to know. While most previous histories of London’s sanitation and drainage have been centered on the larger-scale sanitation schemes of the nineteenth century, this study sheds light on the water infrastructure and administration that preceded these interventions. It shows that eighteenth-century London’s management of water was an iterative process of reactive decision-making rather than a grand plan.

Incorporation of pre- and intra-operative sentinel lymph node mapping techniques in dogs with apocrine gland anal sac adenocarcinoma

The high incidence of nodal metastasis, variable lymphatic drainage patterns, and prognostic significance of nodal metastasis in dogs with apocrine gland anal sac adenocarcinoma (AGASACA) highlight the need for development of standardized techniques for lymph node staging in canine AGASACA. The aim of this study was to develop and describe the utility of pre- and intra-operative sentinel lymph node (SLN) mapping techniques for subsequent nodal extirpation and histologic assessment in dogs with AGASACA. A prospective clinical trial was performed as a pilot study. Eight client-owned dogs with unilateral AGASACA were enrolled. Preoperative contrast-enhanced ultrasound (CEUS) via transrectal ultrasound (TRUS) and CT-lymphography (CTL) was followed by intraoperative SLN mapping within 7 days utilizing a visible dye (methylene blue [MB]) and a near-infrared (NIR) fluorescent dye (indocyanine green [ICG]) with subsequent nodal extirpation and routine anal sacculectomy. In all dogs, preoperative CTL and intraoperative SLN mapping identified at least one SLN. Pre- and intra-operative findings differed in 4/8 dogs. Preoperative CEUS identified a SLN in 7/8 dogs, but the exact location of the SLN was indeterminate. Extirpated lymph nodes were metastatic in 2/8 dogs. Preoperative CTL and intraoperative MB and ICG were an effective combination of SLN mapping techniques in dogs with AGASACA. These techniques each provided unique advantages. Combined, they identified and guided extirpation of early metastatic lymph nodes. Large-scale, prospective studies utilizing the techniques described are needed to accurately determine the incidence and significance of early/occult nodal metastasis in canine AGASACA.