PubMed Health⌕ Search

Biomedical subjects

Bernhard Moriggl

Publications and source records attributed to Bernhard Moriggl.

13 recordsLinked to original sources

An anatomic landmark to simplify subclavian vein cannulation: the "deltoid tuberosity".

The subclavian vein is frequently used to obtain central venous access. Several landmarks exist to determine the puncture site and angle, but they may require patient manipulation and anatomic measurements. We studied the feasibility of using the deltoid tuberosity, located on the lateral aspect of the clavicle, as an anatomic landmark. This would not necessitate these maneuvers and could therefore facilitate subclavian vein access. To systematically investigate this landmark, we conducted a study in four phases: 1) Two blindfolded examiners determined the distance between the tuberosity's medial border and the clavicle's lateral end in 100 dried clavicles and then 2) performed subclavian vein cannulation in 20 fresh human cadavers using the tuberosity and the suprasternal notch as landmarks. 3) Three-dimensional reconstructions of the subclavian artery and vein and surrounding structures were derived from computed tomography datasets of 10 patients. The length of the path of a virtual subclavian vein cannulation with the deltoid tuberosity landmark was measured bilaterally. 4) In a prospective, randomized trial, subclavian vein cannulation was performed in 60 patients with a standard approach or with the deltoid tuberosity as landmark. Interobserver difference between measurements in phase 1 was 3 +/- 1 mm (mean +/- sd); subclavian vein cannulation was achieved in 19 of 20 cases, whereas the subclavian artery was cannulated in one case (phase 2). In phase 3, there was no significant difference in skin-vein distance between the left (4.9 +/- 0.5 cm) and right (4.7 +/- 0.6 cm) sides. In phase 4, subclavian vein cannulation could be performed in all patients; moreover, subclavian vein cannulation was significantly (P < 0.01) faster in the deltoid tuberosity group versus the standard approach group (23 +/- 16 versus 34 +/- 14 s). We conclude that the clavicle's tuberosity may reflect an alternative anatomic landmark to simplify subclavian vein cannulation by minimizing patient manipulation and anatomic measurements.

Adult↗

Trigeminal ganglion and its divisions: detailed anatomic MR imaging with contrast-enhanced 3D constructive interference in the steady state sequences.

BACKGROUND AND PURPOSE: Visualization of the trigeminal system is important for imaging diagnosis but technically challenging. We assessed how well the trigeminal ganglion, its rootlets, and its branches (V1, V2, and V3) are depicted on three high-resolution pulse sequences. METHODS: Twenty-two patients (44 sides) underwent nonenhanced 3D constructive interference in the steady state (CISS) MR imaging. Two of these patients and another 20 (44 sides) also underwent contrast-enhanced 3D CISS and contrast-enhanced 3D time-of-flight (TOF) MR angiographic (MRA) imaging. Appearances of the ganglion, sinus ganglii, ganglion lip, and sensory and motor rootlets in the Meckel cave were assessed. RESULTS: The trigeminal ganglion was shown on enhanced 3D CISS images in all cases, on nonenhanced 3D CISS images in 77.3%, and on enhanced 3D TOF MRA images in 92.9%. Sinus ganglia and lips were demonstrated on 98% of enhanced 3D CISS images. Sensory rootlets were depicted with all 3D CISS sequences but no 3D TOF sequences. V1, V2, and V3 were displayed with all enhanced 3D TOF MRA sequences, 79.5-100% of enhanced 3D CISS sequences, and 0-50% of nonenhanced 3D CISS sequences. CONCLUSION: The enhanced 3D CISS sequence was best for displaying the trigeminal ganglion, sinus ganglii, and sinus lips, whereas the enhanced 3D TOF sequence best displayed the emerging V1, V2, and V3 roots. The enhanced 3D CISS sequence was most useful. Complete MR imaging evaluation of the trigeminal ganglion and roots is best performed by using enhanced 3D CISS and enhanced 3D TOF MRA sequences.

Adult↗

In cadavers, directly measured mucosal pressures are similar for the Unique and the Soft Seal laryngeal mask airway devices.

PURPOSE: We compare the Soft Seal and Unique single-use, plastic laryngeal mask airway devices with respect to intracuff pressure, directly measured mucosal pressure and in vitro elastance. METHODS: Ten fresh male cadavers were studied. Microchip pressure sensors were attached to the following locations: A) the anterior middle part of the cuff side; B) the posterior tip of the cuff; C) the anterior base of the cuff; D) the posterior middle part of the cuff side; E) the backplate; and F) the posterior tube. The size 5 Unique and size 5 Soft Seal were inserted in random order using laryngoscope-guidance. Intracuff pressure and mucosal pressure were documented at 0 to 40 mL cuff volume in 10 mL increments. In vitro elastance was determined between 20 to 40 mL cuff volume. RESULTS: For both devices, mucosal pressure increased with cuff volume at most locations. Intracuff pressures and in vitro elastance (5.2 +/- 0.7 cm H(2)O/mL vs 3.8 +/- 0.4 cm H(2)O/mL, P < 0.0001) were higher for the Unique than the Soft Seal (P < 0.0001), but there were no differences in mucosal pressures at any location or cuff volume. CONCLUSION: Intracuff pressures and in vitro elastance are higher for the Unique than the Soft Seal, but mucosal pressures are similar suggesting that the airway morbidity will be similar.

Aged↗

Lumbar plexus in children. A sonographic study and its relevance to pediatric regional anesthesia.

BACKGROUND: Pediatric regional anesthesia has gained increasing interest over the past decades. The current study was conducted to investigate the lumbar paravertebral region and the lumbar plexus at L3-L4 and L4-L5 by means of sonography to obtain fundamentals for the performance of ultrasound-guided posterior lumbar plexus blocks. METHODS: Thirty-two children (12 boys, 20 girls) with American Society of Anesthesiologists physical status I or II were enrolled in the current study. The lumbar paravertebral region was visualized at L3-L4 and L4-L5 on two corresponding posterior sonograms (longitudinal, transverse). The lumbar plexus had to be delineated, and skin-plexus distances were measured. In a series of five pediatric patients undergoing inguinal herniotomy, ultrasound-guided posterior lumbar plexus blocks at L4-L5 were performed. RESULTS: The children were stratified into three age groups (group 1: > 3 yr and </= 5 yr; group 2: > 5 yr and </= 8 yr; group 3: > 8 yr and </= 12 yr). The lumbar plexus could be delineated at L3-L4 and L4-L5 in 19 of 20 cases in group 1, in 17 of 20 cases in group 2, in 22 of 24 cases at L3-L4 in group 3, and in 16 of 24 cases at L4-L5 in group 3. In all patients, the lumbar plexus was situated within the posterior part of the psoas major muscle. Skin-plexus distances showed statistical significant differences between groups 1 and 3 and between groups 2 and 3. The strongest positive correlation existed between skin-plexus distances and the children's weight. Ultrasound guidance enabled safe und successful posterior approaches to the lumbar plexus, thus resulting in effective anesthesia and analgesia of the inguinal region. CONCLUSIONS: Sonography of the lumbar plexus in children proved to be feasible. Skin-plexus distances correlated with the children's weight rather than with their age. The sonographic findings were fundamental for the performance of successful ultrasound-guided posterior approaches in a small group of pediatric patients.

Aging↗

Ultrasound-guided lumbar facet nerve block: accuracy of a new technique confirmed by computed tomography.

BACKGROUND: Lumbar facet nerve (medial branch) blocks are often used to diagnose facet joint-mediated pain. The authors recently described a new ultrasound-guided methodology. The current study determines its accuracy using computed tomography scan controls. METHODS: Fifty bilateral ultrasound-guided approaches to the lumbar facet nerves were performed in five embalmed cadavers. The target point was the groove at the cephalad margin of the transverse (or costal) process L1-L5 (medial branch T12-L4) adjacent to the superior articular process. Axial transverse computed tomography scans, with and without 1 ml contrast dye, followed to evaluate needle positions and spread of contrast medium. RESULTS: Forty-five of 50 needle tips were located at the exact target point. The remaining 5 were within 5 mm of the target. In 47 of 50 cases, the applied contrast dye reached the groove where the nerve is located, corresponding to a simulated block success rate of 94% (95% confidence interval, 84-98%). Seven of 50 cases showed paraforaminal spread, 5 of 50 showed epidural spread, and 2 of 50 showed intravascular spread. Despite the aberrant distribution, all of these approaches were successful, as indicated by contrast dye at the target point. Abnormal contrast spread was equally distributed among all lumbar levels. Contrast traces along the needle channels were frequently observed. CONCLUSIONS: : The computed tomography scans confirm that our ultrasound technique for lumbar facet nerve block is highly accurate for the target at all five lumbar transverse processes (medial branches T12-L4). Aberrant contrast medium spread is comparable to that of the classic fluoroscopy-guided method.

Aged↗

The incidence of lumbar ligamentum flavum midline gaps.

UNLABELLED: Lumbar epidural anesthesia and analgesia has gained increasing importance in perioperative pain therapy for abdominal and lower limb surgery. The loss-of-resistance technique, used to identify the epidural space, is thought to rely on the penetration of the ligamentum flavum. However, the exact morphology of the ligamentum flavum at different vertebral levels remains controversial. Therefore, in this study, we directly investigated the incidence of lumbar ligamentum flavum midline gaps in embalmed cadavers. Vertebral column specimens were obtained from 45 human cadavers. On each dissected level, ligamentum flavum midline gaps were recorded. The incidence of midline gaps per number of viable specimens at the following levels was: L1-2 = 10 of 45 (22.2%), L2-3 = 5 of 44 (11.4%), L3-4 = 5 of 45 (11.1%), L4-5 = 4 of 43 (9.3%), L5/S1 = 0 of 33 (0%). In conclusion, the present study determined the frequency of lumbar ligamentum flavum midline gaps. Gaps in the lumbar ligamentum flavum are most frequent between L1 and L2 but are more rare below this level. When using the midline approach, the ligamentum flavum may not impede entering the epidural space in all patients. IMPLICATIONS: The ligamentum flavum is a crucial anatomical landmark for the safe performance of epidural anesthesia. However, the present study demonstrates some failure of the lumbar ligamentum flavum as a landmark. This may mean that, using a midline approach, one cannot always rely on the ligamentum flavum as a perceptible barrier to epidural needle advancement.

Cadaver↗

Detailed anatomy of the motor and sensory roots of the trigeminal nerve and their neurovascular relationships: a magnetic resonance imaging study.

OBJECT: The trigeminal nerve conducts both sensory and motor impulses. Separate superior and inferior motor roots typically emerge from the pons just anterosuperomedial to the entry point of the sensory root, but to date these two motor roots have not been adequately displayed on magnetic resonance (MR) images. The specific aims of this study, therefore, were to identify the superior and inferior motor roots, to describe their exact relationship to the sensory root, and to assess the neurovascular relationships among all three roots of the trigeminal nerve. METHODS: Thirty-three patients and seven cadaveric specimens (80 sides) were studied using three-dimensional (3D) Fourier transform constructive interference in steady-state (CISS) imaging. The 33 patients were also studied by obtaining complementary time-of-flight (TOF) MR angiography sequences with and without contrast enhancement. At least one motor root was identified in all sides examined: in 51.2% of the sides a single motor root, in 37.5% two motor roots, and in 11.2% three motor roots. The superior cerebellar artery (SCA) and the anterior inferior cerebellar artery (AICA) contacted the sensory root in 45.5% of patients and 42.9% of specimens. The SCA often contacted the superior motor root (48.5% of patients and 50% of specimens) and less frequently the inferior motor root (26.5% of patients and 20% of specimens). CONCLUSIONS: Three-dimensional CISS and complementary 3D TOF MR angiography sequences reliably display sensory, superior motor, and inferior motor roots of the trigeminal nerve and their relationships to the SCA and AICA.

Adult↗

Cervical and high thoracic ligamentum flavum frequently fails to fuse in the midline.

BACKGROUND: Cervical and high thoracic epidural anesthesia and analgesia have gained increasing importance in the treatment of painful conditions and as components of anesthetics for cardiac and breast surgery. In contrast to the hanging-drop technique, the loss-of-resistance technique is thought to rely on the penetration of the ligamentum flavum. However, the exact morphology of the ligamentum flavum at different vertebral levels remains controversial. Therefore, the aim of this study was to investigate the incidence and morphology of cervical and high thoracic ligamentum flavum mid-line gaps in embalmed cadavers. METHODS: Vertebral column specimens were obtained from 52 human cadavers. On each dissected level, ligamentum flavum mid-line gaps were recorded and evaluated with respect to shape and size. RESULTS: The following variations were encountered: complete fusion in the mid-line, mid-line fusion with a gap in the caudal part, mid-line gap, and mid-line gap with widened caudal end. The incidence of mid-line gaps at the following levels was: C3-C4: 66%, C4-C5: 58%, C5-C6: 74%, C6-C7: 64%, C7-T1: 51%, Th1-Th2: 21%, Th2-Th3: 11%, Th3-Th4: 4%, Th4-Th5: 2%, and Th5-Th6: 2%. The mean width of mid-line gaps was 1.0 +/- 0.3 mm. CONCLUSIONS: In conclusion, the present study shows that gaps in the ligamenta flava are frequent at cervical and high thoracic levels but become rare at the T3/T4 level and below, such that one cannot always rely on the ligamentum flavum as a perceptible barrier to epidural needle placement at these levels.

Cervical Vertebrae↗

The structure and histopathology of the "enthesis organ" at the navicular insertion of the tendon of tibialis posterior.

OBJECTIVE: To investigate the structure, histopathology, and molecular composition of tissue specializations of the tibialis posterior enthesis. They collectively reduce stress concentration at the insertion site and are part of an "enthesis organ." This has implications for understanding the basis of enthesopathy. METHODS: Fifty-two specimens of tibialis posterior and the associated superomedial part of the calcaneonavicular ligament taken from cadavers were sectioned longitudinally and examined by routine histology (42 samples) or immunohistochemistry (10 samples). Serial sections of formalin fixed material were stained with Masson's trichrome, toluidine blue, or hematoxylin, eosin and alcian blue. A panel of antibodies against collagens, glycosaminoglycans, and proteoglycans was used to immunolabel methanol fixed material. RESULTS: The enthesis organ consists of the enthesis itself, the superomedial part of the calcaneonavicular ligament (which may fuse with the tendon), the tendon sheath, and associated accessory bones. The accessory bones lay in a region of fibrocartilage that was present even in specimens where the bones themselves were absent. Degenerative changes were seen at the enthesis, around the accessory bones, and in the walls of the tendon sheath. The navicular and accessory bone entheses, together with the calcaneonavicular ligament, were all rich in fibrocartilage. This immunolabeled for aggrecan, link protein, type II collagen, and versican. CONCLUSION: The complexity of the enthesis organ, and the diversity of sites showing histopathological changes, suggest that enthesopathy may not be located precisely at the osteotendinous junction. It could target a number of adjacent locations, in accord with what happens at other entheses; e.g., in patients with spondyloarthropathy. The prominence of fibrocartilage in the enthesis organ, and the degenerative changes to which it is subject, support the view that spondyloarthropathy has an underlying biomechanical basis.

Aged↗

MR anatomy of the proximal cisternal segment of the trochlear nerve: neurovascular relationships and landmarks.

PURPOSE: To assess the anatomic features and vascular relationships of the proximal portion of the cisternal segment of the trochlear nerve. MATERIALS AND METHODS: In 30 subjects (60 nerves) and in one patient with right superior oblique myokymia (SOM), the anatomy of the trochlear nerve was depicted with three-dimensional (3D) Fourier transformation constructive interference in steady state (CISS) magnetic resonance (MR) imaging, whereas the adjacent vessels were detected with 3D time-of-flight (TOF) MR imaging before and after gadopentetate dimeglumine administration. The images were evaluated with respect to the identification of the trochlear nerve, the distance between the point of exit (PE) and the midline, the visualized length, the vascular relationships, and the distance between the PE and the point of neurovascular contact. RESULTS: 3D CISS MR imaging depicted the proximal cisternal segment of the trochlear nerve in the transverse, sagittal, and coronal planes in 57 (95%), 51 (85%), and 48 (80%) of 60 nerves, respectively. The distance from the midline to the PE was 3-9 mm, and the maximum visualized length of the trochlear nerve was 1-14 mm. An arterial-trochlear neurovascular contact was seen at the root exit zone (REZ) in eight (14%) nerves and at a mean distance of 3.4 mm distal to the PE in 29 nerves (51%). The patient with SOM had arterial-trochlear neurovascular contact at the REZ. CONCLUSION: Use of 3D CISS sequences and 3D TOF sequences with or without gadopentetate dimeglumine enables accurate identification of the proximal cisternal segment of the trochlear nerve and its neurovascular relationships.

Adult↗

Detailed anatomy of the intracranial segment of the hypoglossal nerve: neurovascular relationships and landmarks on magnetic resonance imaging sequences.

OBJECT: The thin hypoglossal nerve can be very difficult to distinguish on magnetic resonance (MR) images. The authors used a combination of sequences to increase the reliability of MR imaging in its demonstration of the 12th cranial nerve as well as to assess the course of the nerve, display its relationships to adjacent vessels, and provide landmarks for evaluating the nerve in daily practice. METHODS: The study group consisted of 34 volunteers (68 nerves) in whom a three-dimensional (3D) Fourier-transformation constructive interference in steady-state (CISS) sequence and a 3D T1-weighted contrast-enhanced magnetization-prepared rapid-acquisition gradient-echo (MPRAGE) sequence were applied. Two trained neuroradiologists collaboratively identified the hypoglossal trigone, preolivary sulcus, 12th cranial nerve, posterior inferior cerebellar artery, vertebral artery, 12th nerve root sleeve, and the hypoglossal canal on each side. The 3D CISS sequence successfully demonstrated the hypoglossal trigone (100% of images), 12th nerve root bundles (100% of images), and 12th nerve sleeves (88.2% of images). The canalicular segment was exhibited with the aid of plain 3D CISS sequences in 74% of images and by using contrast-enhanced 3D CISS sequences and contrast-enhanced MPRAGE sequences in 100% of images. The landmarks that proved useful to identify the cisternal segment of the 12th cranial nerve included the hypoglossal trigone, preolivary sulcus, and 12th nerve root sleeve. Neurovascular contact was identified in 61% of root bundles. The roots were distorted in 44% of these contacts. CONCLUSIONS: The contrast-enhanced 3D CISS sequence consistently displayed the cisternal segment as well as the canalicular segments of the hypoglossal nerve and is, therefore, the best sequence to visualize the complete cranial course of this nerve. Landmarks such as the 12th nerve sleeves can assist in the identification of this nerve.

Adolescent↗