Small Corridor Research Articles

Use of a newly developed minimally invasive bilateral fixed angle locking system in the treatment of pathological pelvic fractures: a case series

BackgroundMetastatic bone disease (MBD) and its complications have a significant impact on patients’ quality of life. Pathological fractures are a particular problem as they affect patient mobility and pose a high risk of non-union. The pelvis is frequently affected by MBD and its fixation is challenging. We present a case series of three pathological sacral fractures treated with a new minimally invasive bilateral fixed angle locking system.Case presentationCase 1 and 2 suffered a pathological transforaminal sacral fracture without adequate trauma in stage 4 carcinomas (gastric cancer and breast cancer). Both were initially treated with non-surgical treatment, which had only a limited effect and led to imminent immobility. Both were operated on with fluoroscopic navigation and underwent transsacral SACRONAIL® stabilisation according to CT morphology (S1 + S2 and S1 respectively). Immediately after the operation, pain decreased and mobilisation improved. Case 3 had a pathological transalar sacral fracture during the 2nd cycle of chemotherapy due to non-Hodgkin’s lymphoma. He soon became immobile and could only move in a wheelchair. The operation was performed with CT navigation due to the very small corridors and an implant was inserted in S1 and S2. The patient reported immediate pain relief and his ability to walk improved over the following months. Despite continued chemotherapy, no wound complications occurred.ConclusionsThe cases show the advantages of the minimally invasive bilateral fixed angle locking system SACRONAIL® in the treatment of patients with pathological sacral fractures. It allows immediate full weight bearing and the risk of secondary surgical complications is low. All cases showed an improvement in pain scores and mobility.

Prototype Model of Forklift with Mecanum Wheel Controlled Using Mobile

Industrial forklifts are used to load and unload goods. Electrical forklifts consume less power to drive the vehicle. In crowded spaces with static and/or dynamic obstacles and small corridors, such as industrial floors, warehouses, offices, and hospitals, multidirectional cars could carry out crucial functions. Mecanum wheel-mounted forklifts have seen several designs developed recently to enhance their multidirectional portability and usefulness. In this project, the center of gravity of the forklift is 67mm from the front axle and mecanum wheel diameter is 60mm. The direction of the mecanum wheel is determined by the direction of the leading edge of the roller, if the roller is pointed left then it is a left wheel and if the roller is pointed right then it is a right wheel. The mecanum wheel is a device that can move a vehicle in all directions, including forward, backward, left, right, diagonal, and more. This design has empowered us to create mecanum wheel-based forklift prototype, showcasing the potential for engineering solution. Key Words: Forklift, Mecanum wheel, multidirectional,

Invasion by Cedrela odorata threatens long distance migration of Galapagos tortoises.

Invasive alien species are among the most pervasive threats to biodiversity. Invasive species can cause catastrophic reductions in populations of native and endemic species and the collapse of ecosystem function. A second major global conservation concern is the extirpation of large-bodied mobile animals, including long-distance migrants, which often have keystone ecological roles over extensive spatial extents. Here, we report on a potentially catastrophic synergy between these phenomena that threatens the endemic biota of the Galapagos Archipelago. We used GPS telemetry to track 140 migratory journeys by 25 Western Santa Cruz Island Galapagos tortoises. We plotted the spatial interaction between tortoise migrations and recently established non-native forest dominated by the invasive tree Cedrela odorata (Cedrela forest). We qualified (a) the proportion of migratory journeys that traversed Cedrela forest, and (b) the probability that this observed pattern occurred by chance. Tortoise migrations were overwhelmingly restricted to small corridors between Cedrela forest blocks, indicating clear avoidance of those blocks. Just eight of 140 migrations traversed extensive Cedrela stands. Tortoises avoid Cedrela forest during their migrations. Further expansion of Cedrela forest threatens long-distance migration and population viability of critically endangered Galapagos tortoises. Applied research to determine effective management solutions to mitigate Cedrela invasion is a high priority.

An Expanded Surgical Corridor of Oblique Lateral Interbody Fusion at L4-5: A Magnetic Resonance Imaging Study.

We introduced a new preoperative method, the "expanded surgical corridor," to evaluate the actual safety corridor, which may expand the possibility of performing oblique lateral interbody fusion (OLIF). Axial T2-weighted magnetic resonance images at the L4-5 disc level of 511 lumbar degenerative disease patients was evaluated. The distance between the medial edge of the left-sided psoas muscle and the major artery was measured as the conventional surgical corridor (CSc). The distance between the major vein and lumbar plexus was measured as the expanded surgical corridor (ESc). The mean CSc and ESc were 13.9 ± 8.20 and 37.43 ± 10.1 mm, respectively. No surgical corridor was found in 7.05% of CSc and 1.76% of ESc, small corridor ( ≤ 1 cm) was found in 27.40% of CSc and 0.59% of ESc, moderate corridor (1-2 cm) was found in 42.07% of CSc and 1.96% of ESc, and large corridor ( > 2 cm) was found in 23.48% of CSc and 95.69% of ESc. A total of 33.83% (45 of 133) of whom were preoperatively categorized as having a limited surgical corridor by conventional measurement, underwent OLIF L4-5 successfully. By using the ESc, only 2.35% were categorized as having a limited surgical corridor. The other 97.65% of the patients had an approachable corridor that could be successfully operated by experienced spine surgeons who employ meticulous surgical dissection and thorough understanding of the anatomical structures. The ESc may represent true accessibility to the disc space for OLIF, particularly at the L4-5 level.

Minimally-invasive tubular resection of thoracolumbar intradural schwannoma.

Minimally invasive surgical (MIS) approaches to the spine are increasingly adopted for intradural pathology. In this setting, they may especially be useful to minimize risk of CSF leakage due to the decreased disruption to paraspinal musculature and minimal dead space. Herein, the authors demonstrate their technique for the resection of an intradural thoracolumbar schwannoma in a 30-year-old woman via an MIS approach using a nonexpandable tubular retractor. Salient points include the use of bayonetted instruments and the technique for dural closure in a small corridor. Indications for this technique are discussed in the context of a series of patients with intradural extramedullary lesions.

Transorbital Microsurgery: An Anatomical Description of a Minimally Invasive Corridor to the Anterior Cranial Fossa and Paramedian Structures.

Objectives Transorbital neuroendoscopic surgery (TONES) has ignited interest in the transorbital access corridor, increasing its use for single and multi-portal skull base interventions. However, the crowding of a small corridor and two-dimensional viewing restrict this access portal. Design Cadaveric qualitative study to assess the feasibility of transorbital microsurgery (TMS). Setting Anatomical dissection steps and instrumentation were recorded for homogeneous methodology. Participants Six cadaveric specimens were systematically dissected using TMS to the anterior cranial fossa and paramedian structures. Main Outcome Measures Anatomical parameters of the TMS craniectomy were established, and the visible and accessible neuroanatomy was highlighted. Results A superior lid crease incision achieved essential orbital rim exposure and preseptal dissection. The orbital roof craniectomy is defined by three boundaries: (1) frontozygomatic suture to the frontosphenoid suture, (2) frontal sinus and cribriform plate, and (3) frontal sinus and orbital rim. The mean (standard deviation) craniectomy was 440 mm 2 (78 mm 2 ). Exposing the ipsilateral optic nerve and internal carotid artery obviated the need for frontal lobe retraction to identify the A1-M1 bifurcation as well as near-complete visualization of the M1 artery. Conclusion TMS is a feasible corridor for intracranial access. Mobilization of orbital contents is imperative for maximal intracranial access and protection of the globe. TMS enables access to the frontal lobe base, ipsilateral optic nerve, and most of the ipsilateral anterior circulation. This cosmetically satisfactory approach causes minimal destruction of the anterior skull base with satisfactory exposure of the anterior cranial fossa floor without sinus invasion.

Post-operative Status of Facial Nerve in Cerebello-Pontine Angle Lesion via Retro-Sigmoid Approach; Complications and Outcome


 Objective: To assess the post-operative status of Facial Nerve in cerebellopontine angle (CPA) lesion via retro-sigmoid approach and also its complications and outcome.
 Materials & Methods: This prospective study was conducted at the Department of Neurosurgery, JPMC Karachi from a period of 10-12-2021 to 10-06-2022.The sample size of our study was 37 patients. All the patients were operated for CPA lesions and followed for three months to assess the outcome efficacy.
 Results: Our study showed that the mean age was 37 years, with a range of 27 to 65 years, in which the males were 18 (48.6%) and the females were 19 (51.4%). Out of 37 patients, 28 (75.7%) were diagnosed with vestibular schwannoma, while 6 (16.2%) were meningiomas, and 3 (8.1%) were epidermoid cysts. Gross total resection was performed in 14 (37.8%) patients, while subtotal resection (STR) in 23 (62.2%). Facial nerve function in terms of House-Brackmann at 3 months was found to be grade I in 26 (70.3%), grade II in 9 (24.3%), grade III in 1 (2.7%), and grade IV in 1 (2.7%).
 Conclusion: The CPA is a small corridor through which important neurovascular structures pass. Identification of CN VII is important in large CPA tumours to preserve facial motor nerve function. For all kinds of CPA lesions, gross total excision should be the aim of surgery.

A Possible Stroke Victim from Pharaonic Egypt

We describe the consequences of a stroke in an adult mummy from ancient Egypt including the differential diagnosis. To our knowledge this is the oldest hemiparalysis to be published in the scientific literature. The mummy, from the 25th Dynasty (c. 747-656 b.c.), was found during excavation of the tomb chapel of Hery (TT 12) and Baqi, of the early 18th Dynasty (c. 1550-1292 b.c.). Seventeen mummified bodies were found in a small corridor connecting the 2 tombs. The mummy labeled Individual 6833 was studied macroscopically and radiologically and was unique in its positioning, the presence of a crutch, and the use of sticks as supports. The body belonged to a woman, between 25 and 40 years of age. The type of mummification was of a high level, with excerebration and evisceration carefully performed. The woman suffered a stroke late in life, with left hemiparalysis after bone growth was completed, and she lived with the results for several years.

Foundations in Spinal Endoscopy

Spinal endoscopy has revolutionized the way spine surgeons deliver minimally invasive care for appropriately selected patients. The evolution of endoscopy has been tumultuous since its beginnings as a "blind" percutaneous procedure to access the disk until the present state, in which complex decompressions and even fusions can be accomplished through subcentimeter incisions. Engineering has played a crucial role in this evolution with advances in optics, illumination, and instrumentation that have allowed surgeons to work safely and efficiently in smaller and smaller corridors. Finally, the adaptation of enhanced recovery after surgery protocols have complemented the benefits offered by spinal endoscopy to help patients return to the quality of life they seek through surgical intervention. In this article, we explore foundational elements of spinal endoscopy and look ahead to the future of this maturing field.

Simulation of Density and Flow Dynamics in a Lagoon Aquifer Environment and Implications for Nutrient Delivery From Land to Sea

The near coastal zone, hosting the saltwater-freshwater interface, is an important zone that nutrients from terrestrial freshwaters have to pass to reach marine environments. This zone functions as a highly reactive biogeochemical reactor, for which nutrient cycling and budget is controlled by the water circulation within and across that interface. This study addresses the seasonal variation in water circulation, salinity pattern and the temporal seawater-freshwater exchange dynamics at the saltwater-wedge. This is achieved by linking geophysical exploration and numerical modeling to hydrochemical and hydraulic head observations from a lagoon site at the west coast of Denmark. The hydrochemical data from earlier studies suggests that increased inland recharge during winter drives a saltwater-wedge regression (seaward movement) whereas low recharge during summer causes a wedge transgression. Transient variable density model simulations reproduce only the hydraulic head dynamics in response to recharge dynamics, while the salinity distribution across the saltwater wedge cannot be reproduced with accuracy. A dynamic wedge is only simulated in the shallow part of the aquifer (<5 m), while the deeper parts are rather unaffected by fluctuations in freshwater inputs. Fluctuating salinity concentrations in the lagoon cause the development of a temporary intertidal salinity cell. This leads to a reversed density pattern in the underlying aquifer and the development of a freshwater containing discharge tube, which is confined by an overlying and underlying zone of saltwater. This process can explain observed trends in the in-situ data, despite an offset in absolute concentrations. Geophysical data indicates the presence of a deeper low hydraulic conductive unit, which coincides with the stagnant parts of the simulated saltwater-wedge. Thus, exchange fluxes refreshing the deeper low permeable areas are reduced. Consequently, this study suggests a very significant seasonal water circulation within the coastal aquifer near the seawater-freshwater interface, which is governed by the hydrogeological setting and the incoming freshwater fluxes, where nutrient delivery is limited to a small corridor of the shallow part of the aquifer.

History of endoscopic and keyhole spinal surgery

Development of endoscopic and keyhole surgery is often considered among the greatest scientific advancements in medicine alongside other scientific breakthroughs such as the discovery of antibiotics and the deciphering of DNA structure. The earliest concept of laparoscopy or endoscopy dates back to the use of instruments to visualize various body orifices as recorded in the notes of Hippocrates dating between 460 and 375 B.C. Adequate exposure of the surgical field which is key to safe surgical procedures required large incisions to identify the anatomical structures in the traditional open surgical approaches, and in an attempt to reduce the iatrogenic tissue trauma, smaller corridors were developed to utilize the technological advancements in magnification and illumination, and more recently navigation. As expected, perioperative morbidity is directly proportional to the extent of tissue trauma and surgical dissection, and the shift toward minimizing tissue dissection and prolonged retraction has been generally associated with earlier mobilization, reduced bleeding, and generally reduced morbidity in comparison to traditional open techniques. The advances in surgical technology, particularly in the light source and smaller cameras allowed the use of smaller incisions and adoption of minimal access surgery in the various surgical disciplines, laparoscopic cholecystectomy evolved as a cultural changing procedure and highlighted the focus on minimizing the surgical morbidity experienced by the patient. In spinal surgery, the evolution of surgical loupes, operating microscope, fiber optic light source, and minimal access surgical tools and retractors, allowed for improved surgical field visualization, resulting in smaller incisions and approaches. The initial adoption started with Lumbar discectomy and spinal stenosis decompression and evolved in other aspects of percutaneous fixation and minimal access fusion techniques applicable to trauma, degenerative disease, and tumors. This brief outline of the development of endoscopic and microscopic keyhole techniques in spinal surgery attempts to touch upon the major developments that paved the way for the large plethora of keyhole spinal surgical techniques currently available from the authors’ perspective.

Corridor width determines strength of edge influence on arthropods in conservation corridors

In fragmented landscapes, edge influence (EI) can be an important driver of ecological change. Multiple edges can interact so that distance to the nearest edge is not an accurate predictor of EI, an issue referred to as ‘interactive EI’. This is especially important in conservation corridors, since their linear nature puts multiple edges in close proximity. We assess how corridor width, an important design variable in conservation corridors, influences EI on arthropod diversity. Arthropods were sampled along the edges of grassland corridors of different widths, and from nearby protected areas (PAs) as reference. The influence of corridor width on edge-related change in arthropod diversity was assessed. This was done at the scale of single corridors, and in comparison to nearby PAs. Corridor width influences EI strength. This was apparent at the local scale, and for those species associated with the corridor interior. At the landscape scale, distance to the nearest edge was more important for the similarity of corridors to PAs than corridor width. This was driven by edge specialists rather than grassland interior species. Interactive EI influences local edge responses, especially for species which avoid edges. Future assessments should incorporate processes operating across larger scales into edge responses. We show that there is much greater conservation value in larger corridors for grassland specialists than smaller corridors, and for a given area of set-aside conservation land, we support the establishment of a few wide corridors over many narrow corridors in production landscapes.

Feasibility and Mass-Benefit Analysis of Aerocapture for Missions to Venus

A numerical assessment of the feasibility of aerocapture at Venus is presented, and the mass benefit of aerocapture is compared with propulsive orbit insertion. This paper considers constraints imposed by entry corridor, deceleration loads, and aerodynamic heating on aerocapture for two vehicle control techniques: lift modulation and drag modulation. Feasibility charts are presented to graphically visualize the aerocapture design space spanning interplanetary trajectory and vehicle performance. Results indicate lift modulation aerocapture is feasible at Venus using existing blunt-body aeroshells. Drag modulation technique is also feasible and an attractive option for small satellites, but merits an additional study due to small corridor width and heating constraints. The peak heat rate is within the capability of existing thermal protection system materials for both control techniques. Delivered mass fraction using aerocapture is compared with propulsive insertion with and without aerobraking. Aerocapture allows 90–250% increase in delivered mass to a 400 km circular orbit compared with propulsive insertion.

The Oblique Corridor at L4-L5: A Radiographic-Anatomical Study Into the Feasibility for Lateral Interbody Fusion.

Cross-sectional radioanatomical study. The aim of this study was to analyze the prevalence, size, and location of the oblique corridor (OC), and the morphology of the psoas muscle at the L4-L5 disc level. Lateral lumbar interbody fusion via the OC has the advantage of avoiding injury to the psoas muscle and lumbar plexus. However, the varying anatomy of major vascular structures and the iliopsoas may preclude a safe oblique access to the L4-L5 level. Five hundred axial magnetic resonance images of the L4-L5 disc level were shortlisted. OCs were categorized into four grades: Grade 0 = no corridor, Grade 1 = small corridor (≤1 cm), Grade 2 = moderate corridor (1-2 cm) and Grade 3 = large corridor (>2 cm). OC location was labeled as antero-oblique, oblique, or oblique-lateral. Psoas morphology was categorized based on a modified Moro's classification, where the anterior section was further subdivided into types AI-AIV. Oblique approach was considered nonviable either when there was no corridor due to vascular obstruction (Grade 0) or when the psoas was high-rising (Types AII-AIV). 10.5% of the selected 449 patients had no measurable OC (grade 0) at the L4-L5 level. There were 35% and 37.2% patients with a grade 1and 2 OC, respectively. The location of the OC was anterior oblique, oblique, and oblique lateral in 3.7%, 89.6%, and 6.7%, respectively. According to the modified Moro's classification, 19.4% had a high-rising psoas. Predominantly, psoas was either in line with the disc (Type I; 30.7%) or low-rising (Type AI; 47.4%). Twenty-five percent of the patients did not have an accessible OC either due to obstruction by vascular structures or due to a high-rising psoas. Hence, proper evaluation of the relevant anatomy preoperatively is recommended for early adopters of this technique, as varying anatomy precludes universal suitability of oblique lateral interbody fusion for the L4-L5 level. 3.

A Qualitative Analysis of a USB Camera for AGV Control.

The increasing use of Automated Guided Vehicles (AGV) in the industry points to a search for better techniques and technologies to adapt to market requirements. Proper position control and movement give an AGV greater movement accuracy and greater lateral oscillations stability and vibration. It leads to smaller corridors and leaner plants, to more relaxed shipment devices, and to greater safety in the transport of fragile loads, for instance. AGV control techniques are not new, but new sensors’ applications are possible, such as USB cameras. In this sense, it is necessary to ensure the sensor is adequate to control system requirements. This work addresses AGVs driven by passive floor demarcations. It presents a qualitative analysis of a USB camera as sensors for AGV control, not yet a common industrial application. We performed the experiments with a small AGV prototype on an eight-shaped lane, varying both camera parameters and AGV parameters, such as linear speed. The AGV uses a USB camera with different image processing settings—different morphological filters structuring elements shapes and sizes, and three different image resolutions—to analyze the factors that affect line detection and control processing. This paper’s main contribution is a qualitative and quantitative analysis for the different sensor configurations. In addition, it discusses the influence sources on camera image as a position sensor. Furthermore, the experiments confirm sensor pertinence for the proposed control system.

Microsurgical Treatment of Paraclinoid Aneurysms by Extradural Anterior Clinoidectomy: The Fujita Experience.

Introduction:Paraclinoid aneurysms pose technical difficulty in their approach, mainly because of their close proximity to neurovascular structures, deeper location, and a smaller corridor. Extradural anterior clinoidectomy is a highly beneficial technique in such cases, making more space to deal with these aneurysms. We describe our method of performing extradural anterior clinoidectomy in such patients.Materials and Methods:A total of 33 cases of paraclinoid internal carotid artery aneurysms presenting to Fujita Health University Banbuntane Hospital, Japan, were included. Females comprised the majority with 32 cases; the mean age was 54.8 years (range: 35–74 years). The mean size of the paraclinoid aneurysm was 5.3 mm (range: 3–12 mm).Results:Nine paraclinoid aneurysms were found projecting dorsally, 7 laterally, and 17 medially (Kazuhiko Kyoshim et al's. classification). An immediate complete occlusion rate of 100% was present. Visual disturbance was found in 6.2% of our patients. One of our patients developed permanent loss of vision.Conclusion:Extradural anterior clinoidectomy enables a better exposure to paraclinoid aneurysms. Precise anatomical knowledge along with microsurgical tactics is required to prevent and manage potential complications to achieve good outcomes.

Surgical Obliteration of Anterior Cranial Fossa Dural Arteriovenous Fistulas via Unilateral High Frontal Craniotomy

Surgical obliteration is generally recommended for anterior cranial fossa dural arteriovenous fistulas (ACF DAVFs) because of a high risk of bleeding and the difficulty of endovascular approaches. Surgical obliteration is generally performed via a frontobasal craniotomy; however, it is slightly excessive over the target fistula. Here, we present 2 cases of ACF DAVFs treated with small craniotomy without frontal sinus involvement and a review of the related literature. We present 2 cases including a 63-year-old woman who presented with a right-sided ACF DAVF that was fed by both ethmoidal arteries and drained into the right cortical veins (case 1) and a 59-year-old man with right-sided unruptured multiple aneurysms and a left-sided ACF DAVF that was fed by the right ethmoidal artery and drained into the left cortical veins (case 2). Case 1 underwent surgical obliteration via a right high frontal craniotomy. Case 2 was simultaneously treated with surgical clipping of the multiple aneurysms via a right lateral supraorbital craniotomy and surgical obliteration of the ACF DAVF via a left high frontal craniotomy. These 2 patients had no neurologic deficits, and complete obliteration of all the lesions was confirmed on cerebral angiography. Constructing a small corridor and a deep working distance in unilateral small high frontal craniotomy may be a slightly unusual approach; however, it is thought to provide sufficient space and a range of microscopic views that facilitate surgical manipulation without requiring extensive bone work.

Estimating Pedestrian Impact on Coordination of Urban Corridors

Pedestrian walk timings at most U.S. traffic signals are run in concurrence with relevant signal phases for vehicular traffic. This usually means that signal operations coordinated for the major street can be interrupted by a pedestrian call. Such an interruption may in practice last for a few minutes, thus causing increased delays and stops for major traffic flows. An alternative to this design is to increase the cycle length and embed pedestrian timings within the ring-barrier structure of the prevailing coordination plan. Both approaches have advantages and disadvantages. A fresh approach offered by this study is a comprehensive experimental design and holistic performance evaluation perspectives. The study examines the two abovementioned treatments of pedestrian timings for a small corridor of five intersections in Utah. The experiments have been done in a high-fidelity microsimulation environment with the Software-in-the-Loop version of the field controller (Econolite ASC/3). Findings show that either approach works well for very low traffic demands. When the traffic demand increases findings cannot be generalized as they differ for major coordinated movements versus overall network performance. While major-street traffic prefers no interruption of the coordinated operations, the overall network performance is better in the other case. This can be explained by the fact that avoiding interruptions is usually achieved at the expense of longer cycle length, which increases delay for everyone in the network.

Mapping Pure Mangrove Patches in Small Corridors and Sandbanks Using Airborne Hyperspectral Imagery

Taijiang National Park (TNP) of Taiwan is the northernmost geographical position of mangrove habitats in the Northern Hemisphere. Instead of occupying a vast region with a single species, the mangroves in TNP are usually mingled with other plants in a narrow corridor along the water or in groups on a small sandbank. The multi-spectral images acquired from the spaceborne platforms are therefore limited in mapping the abundance and distribution of the mangrove species in TNP. We report the work of mapping pure mangrove patches in small corridors and sandbanks in TNP using airborne Compact Airborne Spectrographic Imager (CASI) hyperspectral imagery. Bu considering the similarity of spectral reflectance among three species of mangrove and other plants, we followed the concept of supervised classification to select a few training areas with known mangrove trees, where the training areas are determined from the detailed map of mangrove distribution derived from the field investigation. The Hourglass hyperspectral analysis technique was employed to identify the endmembers of pure mangrove in the training areas. The results are consistent with the current distribution of mangrove trees, and the remarkable feature of a “mangrove desert” highlights a fact that biodiversity can be easily and quickly destroyed if no protection is provided. Some remnant patches located by this research are very important to the management of mangrove trees.

Physical and ecological processes at a moving ice edge in the Fram Strait as observed with an AUV

Small-scale investigations of physical and biogeochemical parameters have been carried out with an autonomous underwater vehicle (AUV) at a moving ice edge in the Fram Strait. The AUV was equipped with various sensors to study the complex interactions between physical and ecological processes along the ice edge and the associated meltwater front. The AUV covered two cross-front sections of 9km and recorded high resolution vertical profiles of the physical and biogeochemical properties between 0 and 50m water depth at a horizontal station spacing of 800–1000m.In both physical and biogeochemical terms, the measurements revealed a complex structure of the water column. The distribution of phytoplankton biomass (chlorophyll a) and nutrients was highly inhomogeneous. Chlorophyll a concentrations of 5µgl−1 were detected at the frontal interface in a small corridor just 2–4km wide and only 5m deep. Nutrients at the surface were depleted, yet, compared to previous studies of this region, were still present in the euphotic zone. Below the euphotic zone, nitrate concentrations of 8µmoll−1 and oxygen saturation values of 100% resulted in a “dome-like” pattern – suggestive of vertical transport processes. Based on these measurements, three different zones featuring individual biogeochemical characteristics were identified in the cross-front sections. Atmospheric forcing and the presence of the melt water front are assumed to be mainly responsible for the complexity of the water column. Localized vertical transport events seem to have occurred before our investigations. Furthermore, wind driven frontogenesis likely contributed to vertical water movements. All processes had an effect on the biological processes along the observed meltwater front.