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D Jalsovec

Publications and source records attributed to D Jalsovec.

14 recordsLinked to original sources
PubMed2001

Weekly quizzes in extended-matching format as a means of monitoring students' progress in gross anatomy.

We compared weekly quizzes in extended-matching format with multiple-choice questions and oral examinations as means of monitoring students' progress in gross anatomy. Students' performance on 19 weekly oral examinations or 10-question quizzes based on extended-matching or multiple-choice formats were correlated with their success on 3 interim examinations and the final comprehensive examination. The Kuder-Richardson formula 20, an estimate of precision of the test, was 0.64 for extended-matching quizzes. Students' performance on interim examinations did not differ significantly. There was a significant correlation between students' mean scores on weekly quizzes and mean scores on interim examinations in both the extended-matching (r = 0.516) and multiple-choice group (r = 0.823). The mean grades (ranging from 2 to 5) on the final exam, based on understanding of anatomical concepts and their application in clinical practice, were significantly higher in extended-matching group (4.8) than in the multiple-choice (4.1) and orally examined groups (3.9) (p < 0.05). We conclude that extended-matching quizzes were at least as effective as multiple-choice quizzes and oral examinations and may be better for acquiring synthetic understanding of anatomical concepts especially in combination with other means of knowledge assessment. We recommend them as a reliable and objective means of monitoring students' performance during a gross anatomy course.

Anatomy↗
PubMed2001

Accessory oval foramen.

We describe an opening with smooth walls in front and medial to foramen ovale which leads to an oblique canal directed towards the fossa pterygoidea. The canal was up to 2.3 mm long and opened near the root of the pterygoid process. We called this opening "foramen ovale accessorium", and found it in 48 of 124 anatomical specimens. The foramen was present in newborns and in those aged over 80 years old on one side but rarely on both sides of the sphenoid bone. Only in a single specimen were there two foramina side by side in front of the foramen ovale. In another case, the foramen ovale accessorium was present in the anterior wall of the canalis ovalis and pointed to the fossa pterygoidea. The localization and direction of the foramen ovale accessorium led us to the conclusion that it housed some of the separate rootlets for the chewing muscles, in this case for mm pterygoidei, mm tensor veli palatini and tensor tympani. The existence and contents of the foramen ovale accessorium is important in surgical interventions on the trigeminal nerve and/or ganglion Gasseri.

Adult↗
PubMed2000

Relation of the ethmoidal cells to the floor of the anterior cranial fossa.

The shape of the anterior part of the anterior cranial fossa undergoes important changes in the postnatal life depending on the degree of pneumatisation of the ethmoid labyrinth and/or the frontal sinus. There exist three possibilities in these relations: 1) From the newborn period up to 9 years of age, in the majority of the cases the cribrous plate is situated at the level of the roof of the ethmoid labyrinth with the width of the ethmoid incisure corresponding to the width of the cribrous plate. 2) In the period from 9-35 years of age, in the majority of cases, the ethmoidal cells are partly or completely incorporated into the floor of the anterior cranial fossa with the width of the ethmoid incisure corresponding to the number of cells forming the floor of the anterior cranial fossa. 3) In the period from 35-80 years of age, the cribrous lamina is in the majority of cases lowered due to the intensive development of the frontal sinus. The medial wall of the ethmoid labyrinth consists of a thin bony strip, the width of which depends upon the degree of lowering of the cribrous plate. Adequate CT imaging may clarify the situation.

Adolescent↗
PubMed1999

Mandibular neuralgia due to anatomical variations.

In our large collection of macerated human adult skulls and disarticulated skulls of young individuals we found cases with an extremely large lateral lamina of the pterygoid process. The medial wall of the infratemporal fossa was defined as its formation by the lateral lamina of the pterygoid process and the medial pterygoid muscle. The muscular part formed two-thirds and the lateral lamina one-third of this wall. In cases of a very large lateral lamina in our specimens nearly the whole medial wall was osseous. The third portion of the trigeminal nerve gives off the lingual nerve and alveolar mandibular nerve in the region of the infratemporal fossa. These two nerves generally passed between the lateral and medial pterygoid muscles to their terminal sites. In cases of extremely large lateral laminae the nerves had to make a curve in their course, following the shape of the enlarged lamina. During contraction of the pterygoid muscles both nerves can be compressed. Since the lingual nerve runs between muscular elements, tension and compression is probably avoided. In contrast, the mandibular nerve fixed between the oval and mandibular foramina cannot avoid tension and compression. The result is possible pain, especially during chewing, and may finally create a trigeminal neuralgia. Similar symptoms could be provoked by a foramen pterygospinale or ovalis canal replacing the foramen ovale.

Adolescent↗
PubMed1998

Development of the cribriform plate and of the lamina mediana.

The development of the cribriform plate and lamina mediana was studied in macerated isolated ethmoid bones in specimens from late fetal life to the stage of its final shape (60 specimens). From fetal life to the first year of age, the ethmoid bone consisted of two separate symmetrical halves which had joined together by the end of the first year. Each half of the future ethmoid bone incorporated the superior, middle and occasionally also the supreme nasal concha. The ossification of the cribriform plate started in the new-born where it initially displayed a vertical position but became horizontal in the course of the first year. At the end of the first year both halves of the ethmoid bone had been united by the formation of the crista galli, lamina mediana and complete ossification of the cribriform plate. The lamina mediana reached its final shape by ten years of age. Each half of the ethmoid bone displayed furrows for the fila olfactoria in the region of the superior and occasionally also of the anterior part of the middle nasal concha. The furrows run in a postero-anterior direction. In the course of our investigations we found three cases where all three nasal conchae formed a unique block thus proving the common origin of these structures from the cartilaginous nasal capsule.

Adult↗
PubMed1997

The frontal sinus and the ethmoidal labyrinth.

In the "standard" anatomic description, the frontal bone and cribriform plate of the ethmoid bone form the base of the anterior cranial fossa. We studied the development of the ethmoidal bone as well as its relations to the frontal bone in macerated disarticulated skull bones and macerated skull bases of 35 individuals between 9 and 35 years of age. In 19 cases the ethmoidal cells were completely or partly uncovered by the frontal bone. In 6 of 19 cases the frontal bone did not cover any of the ethmoidal cells; in 10 further cases the frontal bone covered only the anterior and in 3 cases the anterior and middle ethmoidal cells. In a 60-year-old subject the ethmoidal cells were incorporated in the base of the anterior cranial fossa, a rare finding. Thus, a depressed lamina cribrosa is not the only danger in ethmoidectomy. Based on the present data ethmoidal cells uncovered by the frontal bone may involve a serious risk during ethmoidectomy even if the surgeon remains lateral to the insertion of the middle concha. The discrepancy between common descriptions of this region and our own findings may be related to imprecise data concerning the life stage of the cases described in the literature.

Adolescent↗
PubMed1997

The influence of the dentition on the shape of the mandible.

In the course of life the mandible undergoes substantial morphological and dimensional changes. The changes concerning mandibular angle, relation between the length of the mandibular corpus and ramus as well as roughness in the place of insertion of masseteric and pterygoid muscles do not depend upon age or sex but (apodictical) exclusively upon the dentition. In the complete dentition all masticatory muscles take part in chewing and grinding. The function of the temporal and masseter muscle is (reduced) weakened in partial or complete loss of teeth. The most evident morphological change of the lower jaw consists of an apparent elongation of its corpus resulting in a characteristic senile appearance. Measurements have been performed on 114 macerated mandibles of individuals ranging from 4 months to 68 years of age. The following measures have been taken: number of teeth in the lower jaw, angle between the corpus and ramus of mandible, length of the mandibular corpus, height of the mandibular ramus and angle of the mandibular incisure. The angle between the mandibular corpus and ramus is significantly lower in mandibles with 11 and more teeth (p < 0.001). The length of the mandible is significantly larger (p < 0.02) in mandibles with less than 11 teeth. The mandibular ramus is significantly higher in mandibles with more teeth (p < 0.01). There were no significant differences in the angle of the mandibular incisure within the groups (p > 0.05). The discriminant analysis reveals that 62.3% of the variability of mandibles is dependent upon the number of teeth. The rest of proportional variability of 37.7% is probably due to new circumstances and adjustment of the mandible in the period from tooth extraction.

Adolescent↗
PubMed1993

Variations of the ethmoid labyrinth and sphenoid sinus and CT imaging.

Three hundred macerated and partly isolated postmortem mid-facial bones were studied for the development, variations and dimensions of the structures of the nasal cavity. On 184 axial CT scans of bones (102 male, 82 female) from patients ranging in age from 1 to 90 years old, the dimensions of the ethmoid labyrinth and sphenoid sinus were studied in detail in order to determine which anatomic situation might be unsafe during clinical endoscopic interventions. Six anatomic variations were identified. Most unsafe for surgery seemed to be the following types: type III, in which the anterior diameter of the ethmoid labyrinth was large and the posterior ethmoid and sphenoid diameters were relatively narrow; type V, in which both ethmoid dimensions were large and the sphenoid diameter was narrow: type VI, in which the ethmoid labyrinth had an "hour-glass" shape. Present findings indicate that CT orientation before any endoscopic intervention might help to avoid serious complications.

Adolescent↗
PubMed1993

[Does the alveolar process of the maxilla always disappear after tooth loss?].

The existence of the alveolar process depends on the development of teeth. In edentulous maxillae, the alveolar process disappears in general in the region of incisives, canines and eventually premolars, but it persists in over 80% of cases in the region of molars. The persistence of the alveolar process correlates with the pneumatisation of the alveolar process by the alveolar recess of the maxillary sinus. The sinus may invade the whole alveolar process or only part of it so that in its lower part a thicker bone layer persists. Very rarely the alveolar process disappears completely with the loss of teeth. The deepest recess of the maxillary sinus corresponds to the level of the zygomatic process i.e. to the region of the first and second molar teeth.

Alveolar Bone Loss↗
PubMed1993

[Endoscopic paranasal sinus surgery. The most important anatomic variations of the main paranasal sinus and accessory paranasal sinus].

Anatomic variations of the nasal cavity and paranasal sinuses are described in order of their appearance in endoscopy. Variations of the pyriform aperture are followed by variations of the agger nasi, inferior and middle conchas, inferior and middle nasal meati, and variations of the bulla ethmoidea, uncinate process and fontanelles. Variations of the maxillary sinus are described from their anterior and lateral views. Partial and total septation of the maxillary sinus, variations of its dimensions and its relation to dental roots are stressed. The dimensions of the frontal sinus, frontal bulla or bullae are noted. The variation of the sphenoid sinus and its dimensions and relationships to the structures of the cavernous sinus and the endocranium are described. Pneumatization of the anterior clinoid process and the region around the optic canal by the frontal sinus, ethmoid labyrinth or sphenoid sinus is discussed. Knowledge of these different variations will help the rhinologic surgeon in his orientation during endoscopic surgical interventions.

Adolescent↗