Glabellar Furrows Research Articles

New evidence for five cephalic appendages in trilobites and implications for segmentation of the trilobite head

AbstractHead segments play a critical role in revealing the relationships within major arthropod groups but the accurate determination of their number and relationship is challenging because of the decoupling of dorsal tergites and ventral appendages. In recent decades, trilobites have been considered to have four pairs of cephalic appendages and, commonly, five dorsal segments, which has served as the basis for understanding euarthropod cephalic evolution. Based on multiple analytical techniques applied to well‐preserved soft‐bodied specimens of the Upper Ordovician olenid Triarthrus eatoni and middle Cambrian corynexochid Olenoides serratus, we argue that an additional pair of cephalic biramous appendages occurred just behind the antennae, indicating that trilobites had five pairs of cephalic appendages and six dorsally expressed segments. We propose that the mismatch between the four dorsal furrows and five ventral appendages in Olenoides may be reconciled by considering the morphology of the hypostome that marks the position of the antenna and the bifurcation of the first glabellar furrow that has two muscle attachment sites fused. The fusion of clustered attachment sites of the cephalic biramous appendages may have aided feeding ability by gathering the limb bases close to the mouth.

The trilobite Pseudoblackwelderia lubrica (Damesellidae) from the Cambrian (Guzhangian) Changhia Formation of Northern Anhui, China, and its potential sexual dimorphism

The North China type Cambrian System is well developed in northern Anhui Province. A large number of specimens of the trilobite Pseudoblackwelderia lubrica were collected from the Guzhangian (later Cambrian) Changhia Formation at Fenghuangshan in northern Anhui, China, prompting a redefinition of the species. Our emended diagnosis includes: a cone-shaped glabella that is broadly to acutely rounded anteriorly; three pairs of glabellar furrows; the preglabellar field being absent or very short; the librigena with a narrow lateral border, a broad general field and long genal spine; the pygidium with four rings and a terminal piece on the axis; six or seven pairs of pygidial spines with the anterior five pairs being short, the posterolateral pair being long and stout, the seventh pair being small or absent. The new specimens suggest that Neimengguasps is a junior synonym of Pseudoblackwelderia. Moreover, the presence or absence of paired spines on the posterior margin of pygidium is attributed to potential sexual dimorphism. Qianping Lei [cicelyapple@126.com], Nature Department, Changzhou Museum, Changzhou, Jiangsu Province, 213022, PR China Qing Liu [qingliu1029@yeah.net], Room 104, Unit A, Building Six, Fenghuanghu No. 1, Xinbei District, Changzhou 213125, PR China Shanchi Peng [scpeng@nigpas.ac.cn], State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing 210008, China; Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, PR China.

Early Ordovician Seleneceme (Trilobita) in Ziyang Fauna, South China

ABSTRACT Ziyang Fauna is a significant early Ordovician Floian fossil Lagerstätte, recovered from blackish-grey mud limestone and calcareous mudstone of possible slope facies in the Yangtze platform in Ziyang County, Shaanxi Province, China, distinguished by predominate trilobites, accompanied with graptolites, brachiopods, arthropods and some trace fossils. It is marked by high abundance of exceptionally preserved Seleneceme (Trilobita). Two trilobite species named Caputrotundum bashanense and C. ziyangensis, are reassigned here to Seleneceme based on a detailed study of more than one hundred well-preserved specimens. The taxonomic generic and ontogeny characters of Seleneceme are as follows: cephalon semicircular in outline, with axial spine and genal spines; without eye lobes; glabella subcircular in outline, with deep longitudinal glabellar furrows; thorax and pygidium with much parallel segments. The morphological variation during ontogeny of Seleneceme is characterised by the gradual increase of the length/width ratio (L/W) of the body, but with a constant width/length ratio (W/L) of the cephalon, and also a faster growth rate in the pygidium than in the thorax.

Where and how to use botulinum toxin on the face and neck – Indications and techniques

Botulinum toxin (BT) is a proteinaceous substance that is derived from the bacterium Clostridium botulinum. It was initially used for the treatment of strabismus by Dr. Alan Scott in the late 1970s after which, it was regularly being used for the cosmetic correction of benign essential blepharospasm by the Carruthers couple. Jean Carruthers while treating one such patient noticed an improvement in the glabellar furrows with an effect on the brow of the patient as well. By the late 1980s through the 1990s, BT was used rampantly as an off-label indication to treat glabellar frown lines. In 2002, the US Food and Drug Administration approved the use of BT type A for the treatment of glabellar furrows. This changed the global scene of facial rejuvenation, heralding a new era. Ever since then, BT has proved to be effective and safe for the treatment of dynamic facial rhytides and is currently being used for various indications. These indications and techniques have evolved with a better understanding of the face and neck musculature and their interactions and actions as well as efficacy of the BT formulations. The authors present an overview of the various cosmetic indications of BT for the face and neck along with the approach to injection techniques for various muscle groups involved.

A new oryctocephalid trilobite from the Balang Formation (Cambrian Stage 4) of northwestern Hunan, South China, with remarks on the classification of oryctocephalids

A new trilobite, Longaspis paiwuensis n. gen. n. sp., from the Balang Formation (Cambrian Stage 4) in northwestern Hunan, South China, is described. This rare trilobite adds to an expanding taxonomic list of organisms recognized from the Balang Lagerstätte, a deposit of exceptional preservation from the Cambrian. Longaspis paiwuensis is an unusually large-sized, micropygous oryctocephalid trilobite that has proparian facial sutures, pit-like lateral glabellar furrows, up to 17 thoracic segments, and a distinct medial notch in the pygidium; it lacks marginal spines.The classification of the family Oryctocephalidae is reviewed. Three subfamilies are recognized, and Longaspis n. gen. is assigned to the subfamily Oryctocarinae.

A new high-resolution 3-D quantitative method for analysing small morphological features: an example using a Cambrian trilobite

Taphonomic processes play an important role in the preservation of small morphological features such as granulation or pits. However, the assessment of these features may face the issue of the small size of the specimens and, sometimes, the destructiveness of these analyses, which makes impossible carrying them out in singular specimen, such as holotypes or lectotypes. This paper takes a new approach to analysing small-morphological features, by using an optical surface roughness (OSR) meter to create a high-resolution three-dimensional digital-elevation model (DEM). This non-destructive technique allows analysing quantitatively the DEM using geometric morphometric methods (GMM). We created a number of DEMs from three populations putatively belonging to the same species of trilobite (Oryctocephalus indicus) that present the same cranidial outline, but differ in the presence or absence of the second and third transglabellar furrows. Profile analysis of the DEMs demonstrate that all three populations show similar preservation variation in the glabellar furrows and lobes. The GMM shows that all populations exhibit the same range of variation. Differences in preservation are a consequence of different degrees of cementation and rates of dissolution. Fast cementation enhances the preservation of glabellar furrows and lobes, while fast dissolution hampers preservation of the same structures.

Extreme protomeric development in a burlingiid trilobite from Cambrian glacial erratics of Denmark

AbstractPengia Geyer & Corbacho is a Cambrian burlingiid trilobite with fused trunk segments devoid of any articulation in the anamorphic and epimorphic phases of development. The type species is Pengia fusilis (Peng et al.) from the Wanshania wanshanensis Zone of China. Here we describe a second species, Pengia palsgaardia sp. nov., from the Lejopyge laevigata Zone of the Paradoxides forchhammeri Superzone. It comes from a glacial erratic in Denmark which probably originated in the Alum Shale Formation of Västergötland, Sweden. Pengia palsgaardia is a large burlingiid (~10 mm in length), with 14 fused segments in the trunk whose boundaries are marked by ridges. The axis is narrow, with the axial furrows faintly indicated or effaced across the median. Laterally along the axis and the tapering glabella, symmetrical globular lobes are developed that are pinched at their base. During ontogeny the glabellar furrows are pit‐like adaxially but shallow towards the axial furrow as the globular lobes develop. Their pit‐like appearance in Pengia palsgaardia and some other burlingiid species is not considered similar to the condition seen in oryctocephalid trilobites. A median preglabellar ridge resembling that of Schmalenseeia Moberg develops late in ontogeny but in early ontogeny the preglabellar field resembles that of Burlingia Walcott, Alumenella Geyer & Corbacho and Niordilobites Geyer & Corbacho. This gives Pengia a more basal position in the schmalenseeid lineage, outside the derived Schmalenseeia. In mature specimens the facial sutures in P. palsgaardia are fused, but an ocular suture may have been present. During ontogeny Pengia would have gone through the anamorphic and protomeric protaspid segmental conditions, but articulation between either the cephalon and pygidium, or pygidium and thoracic segments of the trunk never developed so it did not progress beyond the protaspid phase. This extreme protomeric development is considered to be a derived feature in Pengia.

The Downside of Fat: Avoiding and Treating Complications.

Three-dimensional facial volume restoration using fat has become widely accepted as an essential component of facial rejuvenation. Transplanted fat has benefits due to its inherently nonallergenic nature. The versatility of fat grafts allows for their use in all types of facial enhancement-improving the appearance of nasolabial folds, mesolabial grooves, flattened cheeks and upper lips, glabellar furrows, lipoatrophy, acne scars, and temporal hollowing. Yet despite its virtues as the ideal filler, autologous fat has its shortcomings with risks of complications. Our objective in this article is to present a systematic approach demonstrating the complications that can occur with each step of autologous fat grafting in facial rejuvenation and offering pearls to avoid and treat these complications.

Head segmentation of trilobites

Although trilobites have provided research subjects for more than two centuries, their head segmentation has remained unresolved. Four glabellar furrows (SO and S1–S3) marking the segmental boundaries are generally present in the cephalic axis, but there are trilobites with one more pair of furrows, the so-called S4, in the cephalic axis, causing confusion in understanding trilobite head segmentation. Recent advances in developmental biology and palaeontology have shed light on the arthropod head problem, and thus, trilobite head segmentation can be reviewed in the light of this knowledge. Based on the information from the anatomy of exceptionally preserved trilobites and artiopodans closely related to trilobites, it is inferred that trilobite head contains five segments: the anteriormost ocular segment potentially associated with the hypostome, the antennal segment and the following three segments with walking legs. When present, the S4 furrows are situated where the eye ridges meet the cephalic axis of trilobites, indicating that the furrows are incised ‘within’ the anteriormost segment in trilobites with an anteriorly enlarged frontal lobe. Trilobites of the Order Redlichiida, the most primitive stock, show variable conditions in the frontal glabellar conditions, while in other more derived groups, the condition is rather constant. The frontal glabellar condition, therefore, could provide a clue to elucidate the unresolved Cambrian trilobite phylogeny and the Cambrian roots of the post-Cambrian trilobites.

Perception of Age, Attractiveness, and Tiredness After Isolated and Combined Facial Subunit Aging.

Patients often seek help to redress aging that affects various regions of the face (subunits). The purpose of this study was to determine how aging of different facial subunits impacts perception of age, attractiveness, and tiredness. Frontal and lateral view facial photographs of a middle-aged woman were modified using imaging software to independently age different facial features. Sixty-six subjects were administered with a questionnaire, and presented with a baseline unmodified picture and others containing different individual or grouped aging of facial subunits. Test subjects were asked to estimate the age of the subject in the image and quantify (0-10 scale) how "tired" and "attractive" they appeared. Facial subunits were organized following rank assignment regarding impact on perception of age, attractiveness, and tiredness. The correlation coefficient between age and attractiveness had a strong inverse relationship of approximately -0.95 in both lateral and frontal views. From most to least impact in age, the rank assignment for frontal view facial subunits was full facial aging, middle third, lower third, upper third, vertical lip rhytides, horizontal forehead rhytides, jowls, upper eyelid ptosis, loss of malar volume, lower lid fat herniation, deepening glabellar furrows, and deepening nasolabial folds. From most to least impact in age, the rank assignment for lateral view facial subunits was severe neck ptosis, jowls, moderate neck ptosis, vertical lip rhytides, crow's feet, lower lid fat herniation, loss of malar volume, and elongated earlobe. This study provides a preliminary template for further research to determine which anatomical subunit will have the most substantial effect on an aged appearance, as well as on the perception of tiredness and attractiveness. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Perception of Age, Tiredness and Attractiveness after Isolated and Combined Facial Subunit Aging

PURPOSE: The purpose of the present study was to determine how aging of different facial subunits, either isolated or combined, would impact perception of age, attractiveness and tiredness. METHOD: A standardized frontal view facial photograph of a middle-aged woman was modified using imaging software to independently age different facial features. Sixty-six health care workers were administered a questionnaire, and presented with 15 sets of images, one baseline unmodified picture and other images containing different individual or grouped aging of facial subunits. Subjects were asked to estimate the age of the subject in the image and quantify (0-10 scale) how “tired” and “attractive” they appeared. Results were compared with scores for the baseline image. Repeated measurement one-way ANOVA and post hoc Turkey analysis were used to compare multiple variables. Facial subunits were organized following rank assignment regarding impact on perception of age, attractiveness and tiredness. RESULTS: The correlation coefficient between age and attractiveness had a strong inverse relationship of -0.95 confirming that age had a dependant impact on perceived attractiveness. There is also an inversely proportional relationship between tiredness and attractiveness with a correlation coefficient of -0.82. From most to least impact in age, the rank assignment for facial subunits was: full facial aging, middle third, lower third, upper third, vertical lip lines, horizontal forehead lines, jowls, upper eyelid ptosis, loss of malar volume, lower lid fat herniation, deepening glabellar furrows, deepening nasolabial folds. Statistically, brow ptosis and crow’s feet did not impact age. Regarding attractiveness, the rank assignment was: full facial aging, middle third, upper third, lower third, upper eyelid ptosis, jowls, lower lid fat herniation, deepening glabellar furrows, brow ptosis, horizontal forehead lines, vertical lip lines, loss of malar volume. Statistically, deepening of nasolabial folds and crow’s feet did not influence attractiveness. Regarding tiredness, the rank assignment was: full facial aging, middle third, lower lid fat herniation, upper eyelid ptosis, loss of malar volume, upper third. Statistically, lower third, jowls, deepening glabellar furrows, brow ptosis, horizontal forehead lines, vertical lip lines, deepening of nasolabial folds and crow’s feet did not influence tiredness. CONCLUSION: We provide a ranking system based on multiple variable statistical analyses, which can help predict which anatomical subunit will have the most substantial effect on an aged appearance.

Ontogeny of the redlichiid trilobiteMetaredlichia cylindricafrom the lower Cambrian (Stage 3) of South China

A number of immature and mature exoskeletons allow the first detailed description of the ontogeny of the early Cambrian redlichiid trilobiteMetaredlichia cylindrica, from black shale of the Shuijingtuo Formation in Hubei Province, South China. The material includes numerous complete protaspides, within which two stages can be differentiated according to the appearance of a shallow furrow that separates the protopygidial area from the protocranidium. Also, identification of the subsequent ontogenetic stages, including meraspides and holaspides, depends on isolated cranidia that display prominent morphological changes such as the contraction of frontal glabellar lobe, appearance of the fourth pair of glabellar furrows, and modification of the facial suture from proparian to opisthoparian. Incorporating the whole ontogenetic sequence allows us not only to trace the developmental trends of various structures with growth, but also to assign the protaspides to their adults correctly, particularly with the help of meraspid specimens.

Reply: Surgical Procedure for Direct Excision of Glabellar Furrows May Be Problematic

Reply: Surgical Procedure for Direct Excision of Glabellar Furrows May Be Problematic

Surgical Procedure for Direct Excision of Glabellar Furrows May Be Problematic

Surgical Procedure for Direct Excision of Glabellar Furrows May Be Problematic

Radiofrequency (GFX™) Ablation for the Reduction of Glabellar Frowning

A new minimally invasive procedure is described for the reduction of glabellar frowning. Glabellar furrow relaxation or GFX (TM) utilizes bipolar radiofrequency energy targeted at peripheral motor nerve fibers to the depressor muscles of the forehead. This procedure is a useful adjunct in forehead rejuvenation when performed concomitantly with blepharoplasty or forehead lifting in a surgical setting. With proper training the procedure can be performed under local anesthesia in the office setting to produce very natural results. The relevant anatomy and technique is described here in detail because this represents new knowledge in facial plastic surgery. A cohort of patients has been studied for over 12 months demonstrating the efficacy of the relaxation that can be achieved with the procedure. The GFX procedure offers the patients and surgeons an alternative treatment to botulinum toxin A when longer lasting relaxation of the forehead depressor muscles is desired.

Radiofrequency Ablation of Facial Nerve Branches Controlling Glabellar Frowning

Hyperdynamic activity of the corrugator supercilii and procerus muscles causes glabellar furrows. Recently, a novel radiofrequency device has become available that can effectively ablate the efferent nerves controlling corrugator and procerus contraction, producing clinical results that are similar to those of botulinum toxin. To assess the efficacy, longevity of effect, and side effects of the radiofrequency ablation device in the treatment of hyperdynamic glabellar furrows. Four probe entry points were used to access branches of the temporal and angular nerves. Seven and two ablations, respectively, were delivered to each temporal branch and angular nerve. Twenty-nine patients underwent bilateral radiofrequency ablation of temporal branches of the facial nerve and the angular nerves. Abrogation of glabellar furrowing was achieved in 90% of patients. No major adverse events were observed. All patients developed mild to moderate swelling, and nine patients (31%) developed purpura in the treated areas. Sixty-nine percent of patients had effects that lasted 4 months or longer, 41% had effects that lasted 6 months or longer, and 10% had effects lasting longer than 12 months. Radiofrequency ablation of efferent branches of the temporal and angular nerves effectively eliminates corrugator and procerus contraction and concomitant glabellar furrowing.

Periosteal Fixation During Subperiosteal Brow Lift Surgery

To report the efficacy of periosteal fixation combined with Y-to-V scalp incisions during small-incision subperiosteal forehead and brow lift. This is a retrospective case series of 19 patients over 12 months; 16 patients underwent bilateral and 3 unilateral surgery. Unilateral surgery was performed in patients with facial nerve palsy and was augmented with cable suspension. Superior arcus marginalis release and visualization of the supraorbital nerve was achieved using an endoscope or a transblepharoplasty approach. All patients achieved a desirable brow lift and contour, with a mean lift of 2.4 +/- 1.0 mm. The mean follow-up was 11 months. During follow-up, there was no evidence of recurrence of brow ptosis. All patients had an improvement of the glabellar furrows. Minor complications included transient diplopia (n=1), reduced medial upper eyelid sensation (n=1), brief postoperative bleeding from one of the small-incision sites (n=1), and persistent sensory loss involving the central scalp incisions (n=2). No long-term alopecia was noted in any case. Our results suggest that with periosteal fixation combined with Y-to-V scalp incisions, bone fixation is not necessary to achieve a desirable height during small-incision subperiosteal forehead and brow lift.

Bupivacaine-Induced Myotoxicity and Its Effect on Botulinum Toxin Paresis

To determine the effect of the coinjection of bupivacaine with botulinum toxin type A on the degree of muscular paralysis. Enhancement of paralysis could allow a decreased dose of neurotoxin treatment, thus reducing the risk for neutralizing antibody formation. Prospective, randomized, double-blind study. Sixteen consecutive patients undergoing treatment of glabellar furrows received botulinum toxin A reconstituted with bupivacaine 0.75% to one corrugator muscle and botulinum toxin A reconstituted with nonpreserved normal saline to the contralateral muscle. Patients were evaluated on days 0 (injection day), 3, 7, 30, 60, and 90. Patients also completed a questionnaire each visit regarding their assessment of paralysis, asymmetry, and adverse effects. At 1 week after botulinum toxin A injection, 68.8% of the patients showed greater weakness on the bupivacaine-reconstituted side as opposed to 25.0% of patients showing greater weakness on the saline-reconstituted side. At 1 and 3 months, there was no statistical difference in weakness between the saline and the bupivacaine sides. The survey revealed that 56% of the patients had greater pain on the saline side, 31% on the bupivacaine side, and equal pain in 13%. Reconstituting botulinum toxin A with bupivacaine is safe, does not limit efficacy, and does not reduce the degree or relative duration of muscular paralysis. Reconstituting botulinum toxin A with bupivacaine results in faster onset of paresis, possibly due to a synergistic effect of bupivacaine induced myotoxicity. Utilizing bupivacaine may result in less pain for patients.

Ontogeny and evolution of the Early Cambrian trilobite genus Nephrolenellus (Olenelloidea)

The cephalon of Nephrolenellus multinodus and its stratigraphically higher sister-taxon N. geniculatus passed through the same four successive phases of development: entry into phase 2 is defined by a change from a decrease to an increase in the dynamic pattern of distance between the intergenal spine bases relative to cephalic length; entry into phase 3 is defined by the appearance of genal spines; and entry into phase 4 is defined by the effective isolation of glabellar furrow S3 from the axial furrow. Phase transitions were associated with significant changes in allometric growth patterns of the cephalon. Five instars are identified within the early development (phases 1 and 2) of N. multinodus. Despite the general similarity in cephalic ontogeny, significant interspecific differences in patterns of shape change are documented throughout phases 1, 2, and 3 of cephalic development which, with differences in rates of glabellar shape change relative to size (higher in N. multinodus) and ontogenetic loss of glabellar axial nodes (higher in N. geniculates), demonstrate that evolutionary modification to ontogeny was mosaic and complex. Stratigraphic occurrences and a temporal trend towards increased rate of glabellar axial node loss relative to size in N. geniculates are consistent with a hypothesis that N. geniculates was a direct descendant of N. multinodus. However, ontogenetic data are needed for immediate outgroups of Nephrolenellus to determine whether two potential autapomorphies of N. multinodus, which refute such a hypothesis, are indeed unique to this taxon. Nephrolenellus jasperensis is recognized as a junior synonym of N. multinodus.

Relationships of the Ordovician trilobites Celmus and Carmon

The odd little trilobite Celmus has been discussed several times in recent years, but its systematic position has remained uncertain. Interest has been centered on characters of the cephalon. It shares some characters with Carmon, a genus that has not raised as much interest but which may help us to resolve the systematic position of Celmus. In both, a strong ornament and inflated thoracic pleurae give an immediate cheirurid-like appearance. On the other hand, there are such 'ptychopariid' characters as a narrow rostral plate and solenopleurid or dimeropygid-like glabellar furrows. The cheirurid-like thorax is therefore usually regarded as a result of convergent evolution. However, it is shown that Carmon and Celmus are strikingly different in the hypostome and also in some other characters and can hardly be related. It is concluded that Celmus is a cheirurid. The inclusion of convergent dorsal characters and the exclusion of ventral characters misled previous cladistic analyses of its position. Carmon and the Carmoninae Kielan, 1960, may belong to the Calymenidae.