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Infundibulum

An infundibulum is a funnel-shaped organ, cavity, or passage in anatomy, derived from the Latin word for "funnel," and typically serves to channel or direct fluids, cells, or structures within the body.^[1] In the endocrine system, the infundibulum—also called the pituitary stalk—is a hollow, conical extension of gray matter from the hypothalamus that connects to the pituitary gland, facilitating the transport of hormones and neural signals between the brain and the gland.^[2] This structure, normally 2-3 mm thick, enhances with contrast on imaging and plays a critical role in regulating endocrine functions.^[3] Within the female reproductive system, the infundibulum forms the distal, funnel-like end of each fallopian tube, featuring finger-like projections called fimbriae that sweep over the ovary to capture and direct ovulated eggs toward the uterus.^[4] The fallopian tube's infundibulum is part of a segmented structure including the interstitium, isthmus, ampulla, and fimbriae, with a thin muscular wall aiding ovum transport.^[5] In the cardiovascular system, the infundibulum, or conus arteriosus, is a muscular, conical outflow tract in the right ventricle of the heart that elevates the pulmonary valve leaflets and directs blood into the pulmonary artery.^[6] Additionally, in neurovascular anatomy, an infundibulum refers to a symmetrical, conical outpouching at the origin of cerebral arteries, such as the posterior communicating artery from the internal carotid, with a broad base up to 3 mm in diameter that narrows to an apex without forming a neck like an aneurysm.^[7] These structures, visible on angiography in about 7-25% of cases, are generally benign but can progress to aneurysm formation and rupture in rare instances.^[8]^[9]

Human Anatomy

In the Brain

The infundibulum, also known as the pituitary stalk, is a hollow, conical structure composed primarily of gray matter that extends downward from the hypothalamus to connect with the posterior pituitary gland, or neurohypophysis.^[10] This funnel-shaped extension, derived from the Latin term infundibulum meaning "funnel" due to its distinctive morphology, facilitates the integration of neural and endocrine functions within the hypothalamic-pituitary axis.^[11] The structure measures approximately 5-8 mm in length and 2-3 mm in diameter in adults, tapering from its broader hypothalamic base to its narrower attachment at the pituitary.^[12] The infundibulum's composition includes unmyelinated nerve fibers originating from magnocellular neurons in the hypothalamic supraoptic and paraventricular nuclei, forming the hypothalamo-neurohypophyseal tract.^[13] These axons transport hormones such as oxytocin and vasopressin (antidiuretic hormone) synthesized in the hypothalamus directly to the posterior pituitary for storage and release into the systemic circulation.^[14] Additionally, the infundibulum incorporates elements of the pars tuberalis from the anterior pituitary and a central cerebrospinal fluid-filled canal known as the infundibular recess, which extends from the third ventricle through the stalk to the pituitary.^[15] This neural pathway, part of the broader hypothalamo-hypophyseal tract, ensures precise regulation of physiological processes including water balance, reproduction, and stress response.^[16] Blood supply to the infundibulum is provided by the superior and inferior hypophyseal arteries, branches of the internal carotid arteries, which form a capillary plexus along the stalk to support both the neural and vascular components of the hypothalamo-hypophyseal system.^[17] The superior hypophyseal arteries primarily nourish the upper stalk and median eminence, while the inferior hypophyseal arteries supply the lower portions and posterior pituitary, contributing to the portal circulation that links hypothalamic releasing factors to anterior pituitary function.^[18] Clinically, the infundibulum is significant due to its vulnerability to pathology; for instance, craniopharyngiomas, benign tumors often arising from Rathke's pouch remnants near the stalk, can compress or infiltrate the infundibulum, leading to hypothalamic-pituitary dysfunction.^[19] Infarction or transection of the stalk, commonly from trauma, surgery, or vascular compromise, disrupts hormone transport and frequently results in hypopituitarism, characterized by deficiencies in multiple pituitary hormones including growth hormone, gonadotropins, and posterior pituitary hormones, with central diabetes insipidus being a common sequela.^[20] On magnetic resonance imaging (MRI), the normal infundibulum appears as a thin, enhancing structure isointense to gray matter on T1-weighted sequences, with high-resolution 3T MRI delineating its tapering contour; pathological thickening (>3 mm) or disruption signals lesions such as tumors or inflammatory conditions.^[12]

In the Heart

In the human heart, the infundibulum, also known as the conus arteriosus, is a conical pouch originating from the upper and left angle of the right ventricle and extending to the pulmonary valve.^[21] This structure forms the distal portion of the right ventricular outflow tract (RVOT), comprising the smooth-walled conus arteriosus, the ventricular septum, and the right ventricular free wall.^[21] As a muscular, funnel-shaped extension, it directs deoxygenated blood anteriorly and superiorly toward the pulmonary trunk.^[22] The infundibulum's muscular composition plays a key role in cardiac dynamics, particularly during systole when its contraction lifts the pulmonary valve leaflets away from the heart base, preventing interference with ventricular contraction and ensuring efficient ejection of blood.^[23] In adults, this structure typically measures approximately 2-3 cm in length, varying slightly with overall heart size but independent of the broader right ventricle dimensions.^[24] Its funnel-like morphology aids in smooth, unidirectional blood flow, akin to infundibula in other anatomical contexts.^[25] Embryologically, the infundibulum arises from the bulbus cordis during the fourth and fifth weeks of development, with the middle segment—known as the conus cordis—elongating to form the smooth outflow portion of the right ventricle. The proximal bulbus cordis contributes to the trabeculated right ventricle, while conus swellings within the conus cordis fuse to establish proper alignment of the outflow tracts, separating the pulmonary and aortic channels to support parallel circulation.^[26] Misalignment during this process can disrupt ventricular-arterial connections, leading to congenital anomalies. Clinically, the infundibulum is implicated in conditions like tetralogy of Fallot, a congenital heart defect characterized by infundibular stenosis that narrows the RVOT pathway, causing obstruction and right ventricular hypertrophy.^[27] This narrowing often results from anterocephalad deviation of the outlet septum and can be dynamic, exacerbating cyanosis during "Tet spells" triggered by factors such as agitation.^[27] Diagnosis relies on echocardiography as the gold standard, which visualizes the stenosis, associated ventricular septal defect, and overriding aorta to guide surgical intervention.^[27]

In the Lungs

In the human lungs, the infundibulum refers to the short, funnel-shaped passages, also known as alveolar ducts or the proximal portions of alveolar sacs, that connect the respiratory bronchioles to the alveoli, forming part of the respiratory zone where gas exchange occurs. These structures are characterized by thin walls composed primarily of smooth muscle, collagen, and elastic fibers, with no distinct separating boundaries; instead, they are defined by the mouths of adjacent alveoli opening directly into them. The epithelium lining the infundibula is cuboidal in the proximal regions, transitioning to flattened squamous epithelium distally as it approaches the alveoli, facilitating a smooth airflow and minimizing resistance while supporting diffusion. Histological examination via light and electron microscopy reveals the absence of goblet cells and cilia in these distal airways, with occasional club cells (formerly Clara cells) present to secrete protective surfactants.^[28] Each infundibulum typically branches into 2-5 alveolar sacs, which collectively expand the surface area available for gas exchange, allowing oxygen to diffuse across the thin alveolar-capillary membrane into the bloodstream and carbon dioxide to exit in the reverse direction. This arrangement contributes to the lungs' total gas exchange surface area of approximately 140 m², supported by the elastic recoil of the infundibular walls during expiration. Distributed throughout the pulmonary acini—the functional units of the lung—infundibula number in the thousands per lung, with estimates of around 25,000 acini overall, each containing multiple such structures to ensure efficient ventilation at the microscopic level.^[28]^[29] Pathologically, infundibula are vulnerable to conditions like emphysema, where enzymatic degradation of alveolar and infundibular walls by proteases leads to airspace enlargement and loss of elastic recoil, as observed in histological sections showing merged and distorted structures. In pulmonary fibrosis, excessive collagen deposition thickens the infundibular epithelium and interstitium, impairing patency and diffusion, with microscopy revealing fibrous scarring that reduces compliance and gas transfer efficiency. These changes are often confirmed through biopsy samples stained with hematoxylin and eosin, highlighting the transition from normal cuboidal lining to fibrotic obliteration.^[28] Developmentally, infundibula originate from the embryonic lung buds, which arise as evaginations of the foregut endoderm around the fourth week of gestation, branching iteratively to form the respiratory tree. By the pseudoglandular stage (weeks 5-17), precursors to the infundibula emerge within the canalicular phase, with alveoli and associated ducts maturing postnatally; approximately 95% of the final alveolar structures, including infundibula, develop in the first eight years of life, primarily during the first three years, driven by septation and remodeling processes.^[28]

In the Reproductive System

In human female anatomy, the infundibulum forms the funnel-shaped distal end of the uterine tube (also known as the fallopian tube), positioned adjacent to the ovary and opening into the peritoneal cavity via the abdominal ostium. This region is characterized by finger-like projections called fimbriae, which extend toward the ovary, including the specialized fimbria ovarica that adheres to the ovarian surface. The overall uterine tube measures 10-12 cm in length, with the infundibulum comprising its terminal portion, where the lumen widens from less than 1 mm proximally to approximately 4 mm at the infundibulum.^[30]^[31]^[32] The primary function of the infundibulum is to capture ovulated oocytes from the ovary, facilitated by the sweeping motion of the fimbriae during ovulation. Once captured, the oocyte is transported through the uterine tube toward the ampulla—the site of fertilization—via coordinated ciliary beating on the epithelial surface and peristaltic contractions of the underlying smooth muscle. This process ensures the oocyte's movement against the tubal lumen, typically within hours of release, while also allowing sperm ascent from the uterus.^[30]^[33] Histologically, the infundibulum is lined by a simple columnar epithelium featuring ciliated cells and secretory cells, which produce fluid to aid gamete transport; the cilia exhibit longitudinal orientation to propel contents toward the uterus. The wall includes a thin muscularis layer with inner circular and outer longitudinal smooth muscle fibers that enable peristalsis, surrounded by a serosal outer layer. These structural elements vary slightly along the tube, with the infundibulum showing more pronounced mucosal folds and a thinner muscularis compared to proximal segments.^[30]^[34] Clinically, obstruction or blockage of the infundibulum can prevent oocyte capture, increasing the risk of ectopic pregnancy, where implantation occurs within the tube rather than the uterus; such blockages often result from inflammation, adhesions, or prior infections like pelvic inflammatory disease. Diagnostic evaluation of infundibular patency commonly involves hysterosalpingography (HSG), a radiographic procedure that assesses tubal openness by tracking contrast dye flow from the uterus to the peritoneal cavity via the abdominal ostium. Hormonal regulation of ovulation, which influences infundibular activity, occurs indirectly through the pituitary infundibulum's role in hormone release.^[30]^[35]

In Other Organs

In human anatomy, the infundibulum of the hair follicle represents the funnel-shaped upper portion of the pilosebaceous unit, extending from the epidermal surface down to the opening of the sebaceous duct, where it facilitates the emergence of the hair shaft and the expression of sebum.^[36] This region is lined by stratified squamous epithelium similar to the epidermis and is closely associated with sebaceous glands that secrete sebum to lubricate the hair and skin surface.^[36] The infundibular structure serves as a critical interface between the follicle and the external environment, contributing to barrier function while being susceptible to conditions like acne due to its role in sebum delivery.^[37] Within the paranasal sinuses, the ethmoidal infundibulum is a narrow, curved pyramidal passage located in the middle meatus of the nasal cavity, connecting the ostia of the maxillary and anterior ethmoidal sinuses to the frontal recess.^[38] Bounded anteriorly by the uncinate process, posteriorly by the ethmoid bulla, and laterally by the lamina papyracea, it forms a key component of the osteomeatal complex essential for mucociliary drainage and aeration of the anterior paranasal sinuses.^[39] Obstruction of this infundibulum, often due to mucosal inflammation or anatomical variants, can lead to sinusitis by impairing sinus ventilation and promoting bacterial stasis in the maxillary and frontal regions.^[40] The infundibulum of the gallbladder is the transitional funnel-shaped region between the body and neck of this pear-shaped organ, located in the right upper quadrant of the abdomen, where it narrows to join the cystic duct.^[41] This area, sometimes featuring an outpouching known as Hartmann's pouch, is particularly prone to gallstone impaction due to its geometry, which can result in acute cholecystitis if stones obstruct bile flow and cause distal inflammation.^[42] Surgical approaches like laparoscopic cholecystectomy often prioritize careful dissection of the infundibulum to avoid bile duct injury during stone removal.^[43] In the renal pelvis, infundibula are the funnel-like stems that connect the major calyces to the renal pelvis, channeling urine from the papillary tips of the renal pyramids through these expansions into the ureter.^[44] Typically, two to three minor calyces converge to form a major calyx, which drains via an infundibulum into the pelvis, ensuring efficient urine transport while accommodating variations in renal architecture.^[45] Narrowing or stenosis of these infundibula, a rare congenital or acquired condition, can cause upstream dilation of the calyces and progressive hydronephrosis, potentially leading to renal impairment if untreated.^[46]^[47]

Veterinary Medicine

Dental Structures

In veterinary dentistry, the infundibulum is defined as a funnel-shaped, enamel-lined invagination or cup on the occlusal surface of certain teeth in herbivores, typically filled with cementum and extending apically into the tooth structure.^[48]^[49] This structure is prominent in the incisors of horses and the cheek teeth of herbivores such as horses, cows, and sheep, contributing to the complex occlusal morphology of hypsodont dentition.^[50]^[51] In equines, each maxillary cheek tooth features two deep infundibula that invaginate the occlusal enamel and are filled with cementum, providing additional grinding surfaces for processing fibrous forage.^[52] These structures are particularly susceptible to pathology due to their depth; food impaction within the infundibula can lead to caries, exacerbated by developmental cemental hypoplasia where cementum formation is incomplete, often in the apical region.^[49]^[53] Infundibular caries progress to necrosis when bacterial fermentation produces acids that demineralize the cementum and underlying enamel, potentially causing pulp exposure and dental abscesses.^[54]^[55] Veterinary treatment involves removing impacted feed and necrotic tissue using curettes or high-speed drills, followed by restoration with flowable resin composites to seal the defect; severe cases with periapical involvement may require endodontic therapy or tooth extraction to prevent quidding and weight loss.^[56]^[57]^[58] In ruminants such as cows and sheep, infundibula manifest as secondary enamel folds or grooves invaginated into the dentin of hypsodont molars and premolars, forming intricate patterns that enhance the tooth's grinding efficiency during rumination.^[51]^[59] These structures create sharp enamel edges as the occlusal surface wears, allowing effective trituration of tough, abrasive plant material without rapid tooth loss.^[51]^[60] Evolutionarily, infundibula represent an adaptation in herbivorous mammals with hypsodont teeth, where the invaginated enamel prolongs the dentition's functional lifespan by maintaining occlusal integrity amid continuous eruption and abrasion from abrasive diets.^[61]^[62] This feature evolved in response to selective pressures for processing cellulose-rich vegetation, contrasting with the brachydont teeth in humans that lack such invaginations.^[63]

Reproductive Structures

In female mammals, the infundibulum constitutes the funnel-shaped distal end of the oviduct, characterized by delicate walls and an irregular, fimbriated margin that actively captures ovulated ova from the ovary surface.^[64] This structure, equipped with fimbriae for ovum guidance, exhibits species-specific variations in size, mobility, and positioning; for instance, in dogs and cats, it is slightly flexuous with a relatively large abdominal opening often enclosed within the ovarian bursa, while in horses, it displays greater flexuousness and more extensive fimbriae to enhance capture efficiency.^[64] The infundibulum's primary role involves enveloping the ovary or ovulation site to direct ova into the oviduct, preventing loss into the peritoneal cavity, with mobility aiding alignment during ovulation in species like horses and dogs.^[64] Species differences further highlight adaptations for reproductive efficiency. In mares, the infundibulum is notably pronounced, featuring cyclic fluid accumulation that peaks between days -10 and -3 relative to ovulation, correlating with elevated estradiol concentrations during proestrus and estrus, which subsides post-ovulation to facilitate ovum transport.^[65] In cows, the infundibulum presents a wide, asymmetric funnel with a broad fimbriated margin closely applied to the ovary, enabling efficient ovum recovery even during occasional multiple ovulations that can lead to twinning.^[64]^[66] These variations underscore veterinary considerations for breeding management across species. Veterinary pathology often involves the infundibulum, where post-infectious salpingitis can result in adhesions that distort fimbrial positioning or occlude the oviduct, thereby causing infertility by impairing ovum capture and transport.^[67] Such adhesions, commonly bilateral following bacterial ascent from the uterus, reduce fertility rates in affected animals like cattle and horses.^[68] Diagnosis relies on transrectal ultrasonography to detect fluid accumulations or dilatations indicative of obstruction, supplemented by laparoscopy for direct visualization of adhesions and patency assessment in standing or recumbent animals.^[69] Comparatively, the infundibulum enlarges in polytocous species such as pigs, featuring a prominent abdominal opening and extensive fimbriae to accommodate simultaneous capture of multiple ova, supporting litter-bearing reproduction.^[64]

Botany

Morphological Description

In botanical morphology, the term infundibuliform (also known as infundibular) describes a structure shaped like a funnel, characterized by a narrow basal tube that gradually widens toward a broader, bell-like mouth.^[70] This descriptor derives from the Latin infundibulum, meaning "funnel," which originates from the verb infundere, "to pour into," evoking the shape's utility in channeling or directing flow.^[71] The term emphasizes a conical or inverted cone form, where the lower portion tapers narrowly before expanding outward, distinguishing it from other tubular shapes like cylindrical or campanulate forms.^[72] This morphological feature applies primarily to the corolla tubes of flowers, where the petals are fused into a gamopetalous structure—a short, slender basal tube that flares into a wider limb at the apex.^[73] It can also describe certain leaves or bracts exhibiting a similar funnel-like profile, though such usage is less common and typically highlights their role in enclosing or directing associated plant parts.^[74] Structurally, the infundibuliform form often features a tube length that is proportionally shorter than the expanded mouth, facilitating a smooth transition that enhances accessibility.^[75] The infundibuliform shape aids pollination by guiding insects toward the reproductive organs, as the narrowing tube provides a directed pathway while the flaring mouth serves as an attractive landing surface.^[76] This configuration promotes efficient pollen transfer, aligning with the corolla's broader function in pollinator attraction.^[77] Historically, the term has appeared in botanical glossaries since the mid-19th century, with early definitions in works like J. S. Henslow's A Dictionary of Botanical Terms (1857) and M. C. Cooke's A Manual of Botanic Terms (1873), establishing it as a standard descriptor in plant morphology.^[78] The shape bears analogy to funnel-like structures in animal anatomy, underscoring a shared morphological principle across biology.^[79]

Examples in Plants

In the Campanulaceae family, species such as those in the genus Campanula (bellflowers) exhibit classic infundibuliform corollas, characterized by a narrow basal tube that flares outward into a bell-like limb, as seen in Campanula rotundifolia.^[80] These structures are pentamerous and gamopetalous, with the corolla varying from strictly infundibuliform to transitional forms with campanulate elements.^[81] Similarly, in the Solanaceae family, genera like Petunia display infundibuliform corollas, where the fused petals form a slender tube widening into a flat or slightly reflexed limb, as exemplified by Petunia hybrida.^[76] In the related Convolvulaceae family, morning glories such as Ipomoea purpurea feature funnelform corollas that are broadly infundibuliform, with a trumpet-like expansion aiding visual attraction from afar.^[82] These floral examples are often depicted in botanical diagrams as symmetric, radially expanded structures, emphasizing the gradual widening.^[73] Beyond flowers, infundibular structures appear in vegetative parts, such as the sheathing leaf bases in certain monocots like irises (Iris spp.), where overlapping basal leaves form a funnel-like enclosure around the rhizome or stem, providing structural support and water retention.^[83] The functional role of infundibuliform corollas centers on nectar accumulation at the tube base, where the funnel shape directs pollinators—such as bees, butterflies, and moths—toward the nectaries while ensuring contact with anthers and stigma for effective pollen transfer.^[84] This morphology enhances pollination efficiency by channeling visitor movement.^[85] Infundibuliform corollas demonstrate convergent evolution across unrelated families, arising independently in response to similar pollinator pressures; for instance, the funnel-revolver form has evolved at least twice in Loasaceae (Nasa spp.) and related lineages to facilitate bird or insect access.^[86] Such convergence is evident in gamopetalous flowers, where petal fusion into an infundibuliform tube occurs in diverse clades like Solanaceae and Convolvulaceae, adapting to long-tongued pollinators.^[87] Taxonomically, infundibuliform corollas are prevalent in gamopetalous flowers, defined by fused petals forming a basal tube that expands funnel-like toward the apex, distinguishing them from tubular or campanulate variants.^[88]

Other Uses

In Invertebrates

In cephalopods, such as octopuses and squids, the infundibulum forms the outer, disc-like portion of each sucker on the arms and tentacles, characterized by grooves and ridges that enable it to conform to irregular surfaces and create a watertight seal for adhesion. This structure, composed of flexible musculature, works in conjunction with the inner acetabulum to generate suction through hydrostatic pressure changes, allowing precise grasping and manipulation of prey or objects.^[89] Additionally, the infundibulum integrates sensory receptors, including chemosensors and mechanoreceptors, facilitating taste, texture detection, and environmental sampling during feeding and locomotion.^[90] In gastropods, the term infundibulum also denotes a genus of small, marine top snails within the family Trochidae, first described by Pierre Denys de Montfort in 1810, with species exhibiting coiled, funnel-shaped shells adapted to shallow coastal environments worldwide.^[91] Representative species, such as Infundibulum concavum and Infundibulum tomlini, inhabit Indo-Pacific reefs and are herbivorous grazers, their conical shells featuring a wide aperture that reflects the genus name's etymology from the Latin for "funnel."^[92] Beyond taxonomy, infundibulum-like morphology appears in the funnel-shaped apertures or siphonal canals of certain gastropod shells, aiding in water flow for respiration and feeding in species like those in the Buccinidae family, though not exclusively termed as such.^[93] Evolutionary adaptations involving infundibular structures in invertebrates emphasize enhanced adhesion and sensory integration for survival, as seen in cephalopod suckers that evolved from simpler molluscan foot tissues to support predatory locomotion and prey capture in marine habitats.^[94] These features underscore convergent evolution for efficient fluid dynamics in diverse invertebrate lineages.

In Popular Culture

In Kurt Vonnegut's 1959 science fiction novel The Sirens of Titan, the concept of "chrono-synclastic infundibula" is introduced as rare points in space-time where multiple dimensions intersect, leading individuals to perceive reality in fragmented or simultaneous ways, often resulting in profound perceptual shifts.^[95] These fictional phenomena, drawing etymologically from the Latin word for "funnel," serve as metaphorical gateways that underscore themes of determinism and the illusion of free will in Vonnegut's narrative.^[95] In Ian McDonald's 2011 young adult novel Planesrunner, the first book in the Everness series, the "Infundibulum" appears as a mysterious, handcrafted device functioning as a map of the multiverse, enabling travel between parallel worlds and serving as a central plot device for the protagonist's adventures across dimensions.^[96] This usage extends the term's funnel-like connotation to quantum mechanics-inspired portals, emphasizing interdimensional navigation without any grounding in anatomical structures. The term "infundibulum" occasionally surfaces in other science fiction works as a descriptor for portal-like structures or conduits, often evoking funnel-shaped gateways in speculative settings, while fantasy world-building sometimes nods to its etymological roots for naming magical funnels or vortexes.^[95] Vonnegut's invention of "chrono-synclastic infundibula" has notably influenced cultural discussions on relativity, time perception, and alternate realities, embedding the term in broader conversations about nonlinear narratives in literature and media.^[95] These depictions remain purely metaphorical, lacking any scientific basis beyond linguistic inspiration from funnel imagery.

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Deciphering the functions of the hair follicle infundibulum in skin ...
The infundibulum is the funnel-shaped, uppermost part of the hair follicle, acting as a major interface with the environment and involved in skin diseases.Missing: anatomy | Show results with:anatomy
[39]
Anatomy, Head and Neck, Nose Paranasal Sinuses - NCBI - NIH
Ethmoid Infundibulum. The ethmoid infundibulum is a pyramidal space that facilitates the drainage of the maxillary, anterior ethmoid, and frontal sinuses.Introduction · Structure and Function · Embryology · Physiologic Variants
[40]
The Frontal Sinus Drainage Pathway and Related Structures - PMC
The ethmoid infundibulum is the space bounded by the uncinate process anteromedially, the ethmoid bulla posterolaterally, and the lamina papyracea ...
[41]
Flying through congested airspaces: imaging of chronic rhinosinusitis
Jul 27, 2010 · The infundibular pattern relates to the obstruction of the ethmoid infundibulum by soft-tissue thickening, which results in impaired drainage ...
[42]
Anatomy, Abdomen and Pelvis: Gallbladder - PubMed
Oct 31, 2022 · The gallbladder body tapers into the infundibulum, which connects to the neck and cystic duct. At the distal portion of the gallbladder and into ...
[43]
A practical new strategy to prevent bile duct injury during ... - NIH
Jul 8, 2020 · The gallbladder infundibulum is variable in size and shape, and when this funnel-shaped portion is eccentrically inflated, it is called a ...
[44]
Laparoscopic Cholecystectomy - StatPearls - NCBI Bookshelf - NIH
Jul 2, 2025 · The gallbladder consists of 4 regions: fundus, body, infundibulum, and neck. There is considerable variation in the biliary anatomy, which ...
[45]
Revisiting the morphology of pelvicalyceal system in human ... - NIH
The major calyces drain into infundibula. Two infundibula join to form the renal pelvis normally, one from upper pole and one from lower pole calyces, but there ...
[46]
Kidney collecting system anatomy applied to endourology
Mar 18, 2024 · Minor calyces may directly drain to an infundibulum or get together, forming major calyces that subsequently will drain to the infundibulum; ...
[47]
Childhood Infundibular Stenosis - PubMed
Infundibular stenosis is a rare condition marked by dilation of one or more calices proximal to a stenotic infundibulum.
[48]
Congenital infundibulopelvic stenosis: Indications for intervention ...
Not all cases of IFPS require surgical intervention. We have intervened in cases of IFPS with progressive hydronephrosis or worsening renal insufficiency with
[49]
Dental infundibulum - vet-Anatomy - IMAIOS
Dental infundibulum refers to a funnel-shaped cavity or invagination found in the teeth. This structure is lined with enamel and filled with cementum.
[50]
Update on the aetiopathogenesis of equine cheek teeth infundibular ...
Feb 9, 2023 · Each maxillary cheek tooth has two infundibula that are cement(um)-containing cup-like invaginations of the occlusal enamel extending deep ...
[51]
[PDF] Proceedings of the AAEP - Ivis.org
The infundibulum present in all incisor teeth is sometimes termed the “cup” or “incisal cup.” This funnel-like structure is almost circular in shape and in ...
[52]
The oral cavity in cattle - Veterinary Practice
Feb 14, 2024 · Ruminants, on the other hand, have hypsodont teeth. Generally, these teeth have enamel that is invaginated into the dentin to form infundibula ...
[53]
Prevalence, Type and Location of Infundibular Lesions on CT Imaging
Apr 24, 2019 · Equine maxillary cheek teeth each contain two infundibulae that provide additional occlusal enamel ridges to help crush the fibrous, cellulose- ...
[54]
Infundibula of equine maxillary cheek teeth: Part 2 - PubMed
Infundibular cemental hypoplasia was defined as a non-pathological developmental abnormality and was detected in >50% of CT with no evidence of dental diseases.
[55]
Dental Caries in Horses - Digestive System - Merck Veterinary Manual
Infundibular cement hypoplasia predisposes the infundibula to become filled with feed material that can ferment and produce an acidic environment. As these ...
[56]
[PDF] Lack of Cementum in Infundibulum (Hypocementosis)in Equine ...
Jan 3, 2019 · Infundibular necrosis is a bacteria-induced disease characterized by demineralization of larger portions of the tooth [4,5].
[57]
Equine dental caries and restoration - 2023 - Wiley Online Library
Jun 26, 2023 · Infundibular caries are carious lesions that originate within the infundibulum that is impacted with feed. The acidic bacterial by-products of ...
[58]
Long-Term Follow-Up of Restorations of Equine Cheek Teeth ...
Jan 13, 2022 · The equine dental infundibulum (plural: infundibula) is anatomically an invagination of the dental enamel from the occlusal surface in an apical ...
[59]
[PDF] Endodontic Therapy for Periapical Infection of the Cheek Teeth
Periapical abscessation of equine cheek teeth has routinely been treated by removal of the affected tooth.
[60]
LAB 18 Skull
An infundibulum is an infolding of occlusal surface enamel. When enamel is worn it forms a sharp edge. The longer the infolded enamel, the more sharp edges are ...
[61]
The Diversity of Cheek Teeth
Herbivores must efficiently and thoroughly grind their food, which is many cases is hard and abrasive. The addition of hard enamel ridges to the teeth improves ...<|control11|><|separator|>
[62]
The pay-off of hypsodonty - timing and dynamics of crown growth ...
Dec 29, 2018 · When the cuspal crown portions along with the infundibula are worn away in teeth exhibiting tooth base hypsodonty, enamel is located only at the ...
[63]
Common mammals drive the evolutionary increase of hypsodonty in ...
During the past 20 million years, herbivorous mammals of numerous lineages have evolved hypsodont, or high-crowned, cheek teeth. Hypsodonty is informative ...
[64]
An Evo-Devo perspective on ever-growing teeth in mammals and ...
Scrutinizing the diet evolution of hypsodont molars in herbivorous large mammals during climate change has shown that hypsodonty might allow an enlargement of ...
[65]
Oviduct or Fallopian tubes of Animals | Veterinary Physiology
The oviduct may be divided into five parts, namely, infundibulum, magnum, isthmus, uterus and vagina each preserving its own structure and physiological ...
[66]
Accumulation of Fluid in the Infundibulum During the Estrous Cycle ...
Fluid accumulation in the infundibulum increases from day -10 to -3, then decreases, and is linked to estradiol levels during the estrous cycle.
[67]
Reproductive Anatomy and Physiology of Cattle - Select Sires
Nov 5, 2020 · The large funnel-like structure on the open end of the oviduct, the infundibulum, surrounds the ovary, to recover the ova and keeps them from ...Missing: multiple | Show results with:multiple
[68]
Reproductive disorders | Veterian Key
Feb 27, 2017 · Unilateral adhesions of the oviduct or fimbrae may also affect fertility by distorting the oviduct's position relative to the ovary ...
[69]
Uterine tube disease in cattle - AVMA Journals
The UT of cattle is approximately 25 cm long and is grossly divided into the infundibulum, the ampulla, and the isthmus. These anatomic regions are similar in ...Missing: post- | Show results with:post-
[70]
[PDF] Ultrasonography and laparoscopy as a diagnostic tool for evaluation ...
ABSTRACT. The present study was conducted for evaluating genitalia of cows (17) through transrectal ultrasonography. (TRUS) and transabdominal laparoscopy ...Missing: infundibulum | Show results with:infundibulum
[71]
The Epididymis - Veterian Key
Jun 4, 2016 · The epididymis is a single tubule that connects the efferent ductules to the vas deferens and plays important roles in sperm transit, maturation, and storage.
[72]
Infundibuliform Definition and Examples - Biology Online Dictionary
Jun 28, 2021 · 1. Having the form of a funnel or cone; funnel-shaped. 2. (Science: botany) same as funnelform. Origin: L. Infundibulum funnel: cf. F. Infundibuliforme.Missing: etymology | Show results with:etymology
[73]
Infundibulum | Interactive Biology, with Leslie Samuel
Word origin: From Latin infundibulum, literally “a funnel,” from infundere “to pour into” + -bulum, suffix forming names of instruments. In some cases a loan- ...
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infundibuliform - definition and meaning - Wordnik
Specifically— In botany, having the form of a tube enlarging gradually upward and spreading widely at the summit: said of a gamopetalous corolla, as that of a ...
[75]
Corolla Types: 13 Main Types of Corolla (With Diagram)
Regular, gamopetalous corolla with their petals fused to form a tube, as in disc florets of Compositae. Corolla in Plants: Type # 6. Infundibuliform:.
[76]
Infundibular - Steere Herbarium - New York Botanical Garden
Title. Infundibular. Definition. Usually referring to a corolla in the shape of a funnel but can also be applied to other structures with a similar shape.
[77]
Infundibuliform - Cactus-art
An infundibuliform flowers is a flower shaped like a funnel or inverted cone, with petals either fused or overlapping and usually joined into a short tube ...Missing: definition | Show results with:definition
[78]
Corolla of Flower - BYJU'S
Infundibuliform or Funnel-shaped: Datura and several other members of the Convolvulaceae family, including Ipomoea pulchella, have corollas that resemble an ...
[79]
Corolla of Flower - Meaning, Features, Variations and Functions
Infundibuliform or Funnel-shaped: This form of corolla resembles an inverted cone or funnel, as seen in Datura and many members of the Convolvulaceae family, ...
[80]
Details - A dictionary of botanical terms - Biodiversity Heritage Library
Feb 2, 2016 · By. Henslow, J. S. (John Stevens), 1796-1861 ... Cambridge University has a copy of this work that has been inscribed by the author with the date ...
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Infundibulum - Etymology, Origin & Meaning
Originating in 1799 from Latin infundibulum, meaning "funnel," derived from infundere "to pour into," infundibulum denotes a funnel-shaped organ or body ...Missing: botany definition
[82]
Resolving the Evolutionary History of Campanula (Campanulaceae ...
Sep 9, 2011 · Campanula are mostly herbaceous with pentamerous flowers and usually display a campanulate, infundibuliform, tubular, or rotate corolla [7], [8] ...
[83]
Codonographia Gorgonum, or the description of a pleiad of ...
Feb 1, 2021 · feijoana is more widespread and representative of bellflowers with infundibuliform constricted corollas on the island, we conserve the name C.
[84]
Common Morning Glory (Ipomoea purpurea) - Illinois Wildflowers
Each flower is 2–3½" across and about as long; it consists of a funnelform corolla, 5 sepals, a pistil with a single style, and 5 stamens. The corolla is ...
[85]
The folded leaves of Iris - Botany Professor
Jul 5, 2020 · Such folded leaves are called unifacial (one-faced), because both sides are actually the same side - technically the abaxial side. The upper, or ...
[86]
[PDF] FLORA OF NORTHERN ALABAMA, PART 4. BASAL MONOCOTS
Oct 29, 2019 · Leaves sessile, broadly linear, iris-like (leaves basally folded and partly enclosing the next leaf above). 9. Leaves >35 cm long and 5-18 mm ...
[87]
Evidence for nonallopatric speciation among closely related ...
The gynoecium is surrounded by five stamens in the tube of a infundibuliform corolla, leaving limited space to a pollinator to reach the nectar. This floral ...
[88]
A BLADE-ON-PETIOLE orthologue regulates corolla differentiation ...
Aug 8, 2023 · The specific shape of a flower is a product of a long history of plant–pollinator interactions. For example, the formation of corolla tubes ( ...
[89]
Evolution of funnel-revolver flowers and ornithophily in nasa ...
"Funnel-revolver flowers" represent the derived condition, but molecular data suggest a convergent development (at least twice independently), since the ...
[90]
Convergent evolution of floral shape tied to pollinator shifts in ...
Our study provides one of the few empirical demonstrations of the relationship between flower shape and pollination system at a macroevolutionary scale.
[91]
Corolla - What, Shapes, Fusion | Flower | Botany - BrainKart
May 1, 2018 · Infundibuliform: Petals fused to form funnel-shaped corolla. Tube gradually widens into limbs. Example: Datura, Ipomoea. 4. Rotate: Petals ...<|control11|><|separator|>
[92]
Structure and Adhesive Mechanism of Octopus Suckers1
The exposed disc-like portion of the sucker is termed the infundibulum (Girod, 1884) (Fig. 1). When the sucker is active the infundibulum is flattened against ...
[93]
Unveiling the morphology of the acetabulum in octopus suckers and ...
The octopus sucker is a muscular hydrostat [18] composed of three types of muscular bundles: radial, circular and meridional. ... The sucker consists of two ...
[94]
Octopus arms have segmented nervous systems to power ...
Jan 15, 2025 · Octopuses can move and change the shape of their suckers independently. The suckers are also packed with sensory receptors that allow the ...
[95]
https://www.litcharts.com/lit/the-sirens-of-titan/symbols/chrono-synclastic-infundibulum
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https://sf-encyclopedia.com/entry/mcdonald_ian
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Shell characters and taxonomy of Latirus and related fasciolariid ...
Characterization: Last whorl cylindrical to very weakly inflated, with or without low shoulder angulation; axial ribs extending onto long, straight siphonal ...
[98]
Evolutionary development of the cephalopod arm armature: a review
Dec 20, 2021 · These circular structures have later been re-interpreted as the attachment ring (infundibulum) of belemnoid suckers as very similar imprints ...Suckers · Sucker Rings · Belemnoid Arm Hooks
[99]
11.10: Arthropods - Biology LibreTexts
Mar 5, 2021 · Terrestrial arthropods, on the other hand, have special respiratory structures to exchange gases with the air. These are described in Figure ...
[100]
Chrono-Synclastic Infundibulum Symbol in The Sirens of Titan
Chrono-synclastic infundibula, mysterious spirals that exist in space, represent the vast unknowable expanse of the universe and the predetermined nature of ...
[101]
SFE: McDonald, Ian - SF Encyclopedia
River of Gods won the 2005 BSFA Award for best novel; Cyberabad Days (coll ... (2011), whose young protagonist comes into possession of an infundibulum – ...