The Sellar Region as Seen from Transcranial and Endonasal Perspectives: Exploring Bony Landmarks Through New Surface Photorealistic Three-Dimensional Model Reconstruction for Neurosurgical Anatomy Training

BACKGROUND

Virtual reality-based learning of neuroanatomy is a new feasible method to explore, visualize, and dissect interactively complex anatomic regions. We provide a new interactive photorealistic three-dimensional (3D) model of sellar region microsurgical anatomy that allows side-by-side views of exocranial and endocranial surfaces to be explored, with the aim of assisting young neurosurgery residents in learning microsurgical anatomy of this complex region.

METHODS

Four head specimens underwent an endoscopic endonasal approach extended to the anterior and posterior skull base to expose the main bony anatomic landmarks of the sellar region. The same bony structures were exposed from a transcranial perspective. By using a photogrammetry method, multiple photographs from both endocranial and exocranial perspectives, different for angulations and depth, were captured, fused, and processed through dedicated software.

RESULTS

All relevant bony structures were clearly distinguishable in the 3D model reconstruction, which provides several benefits in neuroanatomy learning: first, it replicates bony structures with high degrees of realism, accuracy, and fidelity; in addition, it provides realistic spatial perception of the depth of the visualized structures and their anatomic relationships; again, the 3D model is interactive and allows a 360° self-guided tour of the reconstructed object, so that the learner can read the bones and their anatomic relationship from all desired points of view.

CONCLUSIONS

Detailed knowledge of key surgical landmarks representing keyholes and/or anatomic structures to not violate is mandatory for safer surgery, especially for a complex region such as the skull base. Highly accurate virtual and functional neurosurgical models, such as photogrammetry, can generate a realistic appearance to further improve surgical simulators and learn neuroanatomy.

Exploring the association between PITX2, third molars agenesis and sella turcica morphology : PITX2, third molars agenesis and sella turcica morphology

OBJECTIVES

PITX2 is required for mammalian development and single nucleotide polymorphisms (SNPs) in this gene could be involved in dental agenesis and sella turcica patterns. Thus, the present study evaluated the association between SNPs in PITX2, third molars agenesis and sella turcica phenotypes.

MATERIALS AND METHODS

The sample consisted of healthy orthodontic German patients with lateral cephalometric radiographs with clearly visualization of the sella turcica, and dental orthopantomograms. The morphological variations of the sella turcica were evaluated using the lateral cephalograms, while third molar agenesis was evaluated using orthopantomograms. DNA isolated from buccal cells was used for genotyping three SNPs in PITX2 (rs3796902, rs1947187, and rs2595110). The analyzes were performed using a significance of 5%. There was no association between third molar agenesis and sella turcica phenotypes (p > 0.05). SNPs in PITX2 were also not associated with third molars agenesis (p > 0.05).

RESULTS

SNPs in PITX2 were associated with sella turcica phenotypes. The rs3796902 was associated with hypertrophic posterior clinoid process (p = 0.013). The rs1947187 and rs2595110 were associated with sella turcica bridge type A (p = 0.013 and p = 0.011, respectively for genotype distribution). Patients that carry the genotypes GG-CC-AG (rs3796902- rs1947187- rs2595110) had 7.2 higher chance to present sella turcica bridge type A (p = 0.002; Odds ratio = 7.2, Confidence interval 95% 2.04-27.04).

CONCLUSIONS

Third molar agenesis was not associated with SNPs in PITX2 and sella turcica phenotypes. SNPs in PITX2 may have an important role in sella turcica pattern.

Anatomical variations of foramen of the diaphragma sellae and neighboring structures: a cadaveric study

The aim of our study was to examine the variations and types of foramen of diaphragma sellae (FDS) and their relationship with nearby surgical landmarks on cadavers.Twenty adult (9 male, 11 female) formalin-fixed cadaveric heads were bilaterally used to analyze the anatomical relationships around the supradiaphragmatic region of sella turcica. Lengths and distances of nearby surgical landmarks were measured by a digital microcaliper. SPSS version 25 was used to analyze the comparison between genders and body sides. Dorsum sellae distances to tuberculum sellae and the optic chiasm(OC) were higher in males than females (p < 0.05). Type 8 infundibulum passage was the most common variation with 50%. There was no finding related to types 1-4 of infundibulum passage. Thus, the present study has indicated that the infundibulum passes mostly from the posterior half of the foramen. The shape of the foramen was irregular in 45%, circular in 20%, sagittally oval in 20%, and horizontally oval in 15% of the cases. The OC was noted normal in 60%, prefixed in 35%, and postfixed in 5% of the cases. Comprehensive anatomical knowledge about the types of the FDS and their neighboring structures is crucial for preoperative planning of sellar region diseases in terms of navigating the region when accessing the foramen. Discrimination of variations of FDS, OC, and pituitary stalk, their relationships, and differences between genders is useful to minimize potential surgical complications.

Morphological and Metrical Relationships Between Sphenoid Sinus and Sella Turcica: Possible Applications in Transnasal Transsphenoidal Surgery

INTRODUCTION

Transsphenoidal surgeries imply the risk of intraoperative lesions to the neurovascular structures surrounding the sphenoid sinus (SS). Aim of the present study is to assess the metrical and morphologic relationships existing between SS and sella turcica (ST).

MATERIALS AND METHODS

Two hundred computed tomography-scans of patients were selected. For each patient volumes of SS were calculated from their 3-dimensional models segmented through ITK-SNAP program. Variants of SS in pneumatisation and sellar diameters [antero-posterior (AP) diameter, depth, and length] were evaluated on each computed tomography-scan. Correlations among different measurements were assessed through Spearman test ( P <0.01), whereas associations between sellar parameters and presence of pneumatisation variants were assessed through Mann-Whitney test ( P <0.01).

RESULTS

In males, pneumatization of the greater wings was related to smaller AP diameter ( P <0.01) and depth of ST ( P <0.01), whereas in females lower values of depth were found in patients with pneumatization of the pterygoid processes ( P <0.01). In both sexes, a positive correlation was found between AP diameter and, respectively, length and depth of ST ( P <0.01), together with a negative correlation between volume of SS and depth of ST ( P <0.01). Lastly, in females a positive correlation was found between age and, respectively, length and depth of ST ( P <0.01).

CONCLUSIONS

The present study highlighted new metrical and morphologic relationships between volume and pneumatisation of SS and diameters of ST. Knowledge of these correlations allows to understand more clearly, in the preoperative setting, the surgical working space. Further studies are needed, especially for what concerns the relationship between sellar measurements and age in females.

Endoscopic Anatomical Study of the Glabellar Keyhole Approach

AIM

To observe the exposure range of a neuroendoscope through the glabellar approach and measure the anatomical parameters to provide a basis for clinical application.

MATERIAL AND METHODS

A total of 10 adult cadaveric heads fixed with formalin were dissected by stratified local anatomy and simulated operation. The length of each point was measured from the corresponding anatomical mark of the anterior fossa on the bone window plate and analysed to clarify relevant surgical indications and feasibility to provide an anatomical basis for clinical application.

RESULTS

The distance from the lower boundary of the bone window to the left anterior clinoid process was (61.97 ± 3.51) mm, the distance to the right anterior clinoid process was (62.21 ± 3.20) mm, the distance to the leading edge of the optic chiasma was (67.40 ± 5.38) mm, the distance to the sellar tubercle was (57.91 ± 2.64) mm, the distance to the centre of the saddle septum was (68.45 ± 4.88) mm; the distance to the midpoint of the endplate was (67.86 ± 4.91) mm, the distance to the anterior communicating artery was (60.89 ± 6.17) mm, the distance to the left posterior clinoid process was (67.56 ± 3.84) mm, the distance to the right posterior clinoid process was (66.78 ± 3.23) mm, the distance to the bifurcation of the left internal carotid artery was (69.45 ± 2.34) mm and the distance to the bifurcation of the right internal carotid artery was (68.01 ± 3.53) mm.

CONCLUSION

The neuroendoscopic glabellar approach can effectively expose the anatomical structures of the midline anterior skull base and both sides near the sellar area and can be used to look for lesions in the midline anterior skull base.

Expanded endoscopic endonasal approach for extending suprasellar and third ventricular lesions

BACKGROUND

Expanded endonasal approaches can provide direct access to the midline skull base from the anterior cranial fossa to the ventral foramen magnum. Surgical strategies of bone drilling, dural opening, and intradural dissection can determine the area of surgical exposure and instrument handling, affecting the safety of devascularizing/debulking suprasellar tumors.

METHODS

We describe an expanded endoscopic endonasal approach for suprasellar lesions, with stepwise image-guided dissections highlighting surgical pearls and pitfalls to enhance surgical safety. This article presents transnasal intra-third-ventricular anatomy from trans-tuber cinereum, and trans-lamina terminalis approaches, comparing subchiasmatic and suprachiasmatic trajectories.

CONCLUSION

The rostral extension via endoscopic endonasal transsellar-transtubercular-transplanum approaches can provide a safe and feasible route for suprasellar lesions, in subchiasmatic, suprachiasmatic, and intraventricular regions.

Risk Factors for Patient-Reported Olfactory Dysfunction After Endoscopic Transsphenoidal Hypophysectomy

Importance

Iatrogenic olfactory dysfunction after endoscopic transsphenoidal hypophysectomy (ETSH) is an overlooked complication without elucidated risk factors.

Objective

To assess the independent prognostic role of demographic, comorbidity, cephalometric, intraoperative, histological, and postoperative parameters in patient-reported postoperative olfactory dysfunction, and to explore the association between anatomical measurements of the skull base and sinonasal cavity and postoperative olfactory dysfunction.

Design, Setting, and Participants

This retrospective cohort study in a tertiary care medical center enrolled consecutive patients with primary sellar lesions who underwent ETSH between January 1, 2015, and January 31, 2019. Patients were excluded if they underwent multiple sinonasal surgical procedures, presented with a sellar malignant neoplasm, required an expanded transsphenoidal approach, had nasal polyposis or a neurodegenerative disease, or sustained traumatic brain injury. After undergoing medical record review and telephone screening, patients were asked to participate in a 3-item telephone survey.

Main Outcomes and Measures

The primary outcome was the Clinical Global Impressions change in smell rating, a validated transitional patient-reported outcome measure. Patients rated their change in smell before and after ETSH on a 7-point Likert scale, with the following response options: (1) much better, (2) somewhat better, (3) slightly better, (4) neither better nor worse, (5) slightly worse, (6) somewhat worse, or (7) much worse. Responses of slightly worse, somewhat worse, and much worse were surrogates for postoperative olfactory dysfunction status. Patient medical records, preoperative imaging scans, operative notes, and pathology reports were reviewed.

Results

Of the 147 patients (mean [SD] age, 54 [15] years; 79 women [54%]) who responded to the telephone survey, 42 (29%) reported olfactory dysfunction after ETSH. Median (interquartile range [IQR]) time between the ETSH completion and survey response was 31.1 (21-43) months. On multivariable analysis, abdominal fat grafting (adjusted relative risk [aRR], 2.95; 95% CI, 1.89-4.60) was associated with postoperative olfactory dysfunction, whereas smoking history (aRR, 1.54; 95% CI, 0.95-2.51) demonstrated a clinically meaningful but imprecise effect size. A more obtuse angle between the planum sphenoidale and face of the sella turcica on sagittal imaging was protective (aRR, 0.98; 95% CI, 0.96-0.99). Increased number of months after the ETSH was associated with patient-reported normosmia (aRR, 0.93; 95% CI, 0.91-0.95). In contrast, other comorbidities; intraoperative variables such as turbinate resection, nasoseptal flap, and mucosal or bone grafting; histological variables such as pathology and proliferative index; and postoperative variables such as adjuvant radiotherapy were not associated with postoperative olfactory dysfunction.

Conclusions and Relevance

This study found that abdominal fat grafting, acute skull base angle, and smoking history appeared to be clinically significant risk factors for patient-reported postoperative olfactory dysfunction. Increased time after ETSH may be associated with better olfactory outcomes.

Neurosurgical Anatomy of the Internal Carotid Artery: Magnetic Resonance Imaging Study of the Sellar Region

BACKGROUND

Transsphenoidal surgical approaches involve dissection of the posterior wall of the sphenoid sinus in close proximity to the internal carotid arteries. To reduce the risk of vascular injury, a detailed study of embalmed cadavers' sellae was conducted and found the internal carotid artery approached within 4 mm of the midline in 10% of cases, and the closest intercarotid distance (ICD) occurred in the cavernous sinus, sphenoid sinus, and supraclinoid segments in 82%, 14%, and 4% of cases, respectively. These measurements have not previously been compared with living patients with modern imaging techniques.

METHODS

This study measured the closest ICD of 233 coronal magnetic resonance imaging head scans from 183 patients (male = 88, female = 95) at the cavernous sinus, sphenoid sinus, or supraclinoid segments of the internal carotid artery. ICD at the sphenoid sinus was taken for all scans.

RESULTS

The internal carotid approached within 4 mm of the midline in 1.3% of cases. The closest ICD occurred in the cavernous sinus, sphenoid sinus, and supraclinoid segments in 24.5%, 35.8%, and 39.7%, respectively. Both results were significantly different from previous cadaveric studies (chi-squared tests, P = 1.4 × 10^-4 and P = 6.1 × 10^-8, respectively).

CONCLUSIONS

Surgically relevant measurements of the carotid arteries in the sellar are different in cadavers and living subjects. This is likely due to postmortem changes of surrounding structures. This study suggests clinically relevant anatomic studies using measurements taken from cadaveric specimens be updated with modern imaging techniques taken from living patients.

Association Between Variations In Sella Turcica Dimensions And Morphology And Skeletal Malocclusions

BACKGROUND

The growth of sella turcica is completed early in life, therefore it can be used as a stable landmark for the prediction of future skeletal malocclusions. This early diagnosis may help in planning less complicated treatment modalities. Therefore, this study aimed to evaluate the relationship between sella turcica dimensions and morphology with various skeletal patterns.

METHODS

A cross sectional study was conducted using the pre-treatment cephalograms of 180 subjects aged 13-19 years. The subjects were divided into two groups based on skeletal patterns. The dimensions of sella turcica and skeletal patterns were digitally measured using View Pro-X software. One-way ANOVA was applied to compare sella turcica dimensions among skeletal patterns. Sella dimensions and vertical growth patterns were compared using Post-hoc Tukey test. Chi-square test was applied to compare sella morphology among malocclusion groups. Results were taken as statistically significant at p-value of ≤0.05.

RESULTS

Sella dimensions showed insignificant differences among sagittal groups whereas, significant differences were found for sella length (p≤0.02) and depth (p≤0.03) among the vertical groups. Multiple comparisons showed significant differences between sella length (p≤0.03) and diameter (p≤0.04) between normodivergent versus hyperdivergent groups. Moreover, significant differences were found in the sella turcica morphology among sagittal malocclusion (p≤0.03).

CONCLUSIONS

Increased dimensions of sella turcica were associated with hyperdivergent growth pattern. Bridging of the sella turcica was found to be prevalent in class III malocclusion.

Evaluation of Sella Turcica Shape and Dimensions in Cleft Subjects Using Cone-Beam Computed Tomography

OBJECTIVE

The aim of this study was to assess the morphology of the sella turcica and measure its size in cleft and noncleft subjects.

MATERIAL AND METHODS

Cone-beam computed tomography (CBCT) images of 54 individuals (29 males; 25 females) with cleft and 85 (22 males; 63 females) without cleft were used for this study. Syndromic patients with cleft(s) were not included because of possible additional endocrinological and/or morphological disorders. Linear measurements included length, depth, and diameter. The shape of the sella turcica was analyzed in the cleft and noncleft groups. An independent t test was conducted to evaluate differences between genders and groups. One-way ANOVA was used to compare age groups.

RESULTS

The length (p < 0.001) of the sella turcica was smaller in noncleft subjects than in cleft subjects. Diameter (p = 0.014) and depth (p = 0.005) showed as constantly increasing from an age <15 to >25 years in the overall assessment. The distribution of the shape of the sella turcica differed significantly between groups (p < 0.001).

CONCLUSIONS

In this study, CBCT was used to assess the morphology of the sella turcica. A majority of the subjects with cleft had a flattened sella turcica compared to that of the control group. A shorter length of the sella turcica was more evident in the cleft subjects than in the control group.

Sella turcica: an anatomical, endocrinological, and historical perspective

INTRODUCTION

The sphenoid bone has a superior depression called the sella turcica, Latin for "Turkish saddle," where the pituitary gland is found. The availability of modern radiological imaging techniques has replaced plain radiography of the sella turcica in the investigation of hypothalamo-pituitary abnormalities. However, the size of the sella turcica, and smaller sella turcica size in particular, may cause pituitary dysfunction because of the changes in the structure of pituitary gland or may be associated with some genetic or acquired endocrine disorders. The name "sella turcica" is one of the most commonly used terms in everyday endocrine practice.

METHODS

In this review, after a brief explanation of the anatomical and endocrinological features of the sella turcica had been given, a historical perspective of sella turcica nomenclature was presented for the first time.

FINDINGS AND CONCLUSIONS

After Andreas Vesalius's description of it as a suitable cavity for the gland that receives the "phlegm of the brain" in De Humani Corporis Fabrica (1543), medical scholars began to use seat/saddle-related terms such as the ephippium, pars sellaris, sella equina, sella ossis, and sella sphenoidalis. The real designation of the sella turcica, however, was introduced to the anatomical nomenclature by the anatomist Adrianus Spigelius (1578-1625) in his famous work De Corpora Humanis Fabrica (1627).

Sphenoid sinus types, dimensions and relationship with surrounding structures

The human sphenoid sinus is an extremely variable cavity and an important landmark in hypophyseal surgery. The aim of this study was to investigate the relationship between the sphenoid sinus type, size, extent of pneumatization and occurrence of protrusions of the adjacent neurovascular structures. A total of 51 randomly selected skulls (≥20 years of age, 33 male; 102 sinuses) were analyzed using cone beam computed tomography to estimate pneumatization extension beyond the body of the sphenoid (planum sphenoidale, pterygoid process, greater wings, clivus, dorsum sellae) and protrusions of the maxillary, mandibular, optic or pterygoid nerve or the internal carotid artery. Difference in pneumatization type between the left and the right-sided sinus was observed in 45% of the skulls. Conchal pneumatization was registered in 2%, presellar in 24%, sellar in 41% and postsellar in 33% of total sinuses. Presellar sinuses frequently pneumatized planum sphenoidale and sporadically other structures, and were characterized by sporadic optic nerve protrusions. Sellar and particularly postsellar sinuses were characterized by simultaneous pneumatization extensions and neurovascular protrusions. In the case of postsellar-type sinuses, the probability of these multiple interactions was not affected by their actual size, while it increased with the increasing sinus dimensions in the case of sellar-type sinuses. A more detailed analysis indicated that increasing sinus height, length or width increased the probability of interactions and pneumatization of particular surrounding structures. Data suggest that the sphenoid sinus pneumatization type and dimensions might be used to estimate the risks of iatrogenic injury during transsphenoidal surgical procedures.

Identification of the internal carotid artery at the superior part of the cavernous sinus during endoscopic endonasal cavernous sinus tumor surgery

BACKGROUND

Identification of the internal carotid artery (ICA) is essential for successful endoscopic endonasal cavernous sinus tumor surgery. This study aimed to develop a method for identifying the ICA in cavernous sinus tumors at the superior part of the cavernous sinus.

METHODS

Ten fresh cadavers were studied with a 4-mm 0° and 30° endoscope to identify surgical landmarks of the ICA in the cavernous sinus. Clinical cases of cavernous sinus tumors were surgically treated using an endoscopic transpterygoid approach.

RESULTS

Anatomical study indicated the ICA at the superior part of the cavernous sinus can be identified using three steps: 1) exposure of the optic nerve sheath by drilling the optic canal; 2) identification of the proximal orifice of the optic nerve sheath at the transition of the optic nerve sheath and dura mater of the tuberculum sellae; and 3) identification of the clinoid segment of the ICA at the distal dural ring just below the proximal orifice of the optic nerve sheath. Although the ICA was encased and transposed by tumors in preliminary surgical cases, the clinoid segment of the ICA was safely exposed at the superior part of the cavernous sinus using this method.

CONCLUSIONS

Dural structures around the cavernous sinus are key to identifying the ICA at the superior part of the cavernous sinus. This method is expected to reduce the risk of ICA injury during endoscopic endonasal surgery for cavernous sinus tumors.

Differences in craniofacial characteristics in Southern Italian children from Naples: a retrospective study by cephalometric analysis

AIM

The present cross-sectional survey was performed to determine cephalometric standards in a large sample (n. 1071) of children from Southern Italy (Naples).

MATERIALS AND METHODS

1071 lateral cephalograms of healthy children, between 8 to 12 years, with various types of occlusion, all with no history of orthodontic treatment before cephalometric analysis were examined. Seven angular and three linear length measurements (SNA, SNB, ANB, SN^GoMe, PN^Pal I^SN, i^GoMe), and three ratios were included. Descriptive statistics, including the mean, standard deviation, and maximum and minimum, values was computed for each cephalometric variable.

RESULTS

Changes in angular and linear parameters during the observation period occurred mostly between the ages of 10 and 12 years. The three ratios varied from age and were not characterised by a progressive rise in mean values. Se-N/Go-Pg was greater in 11-year-old boys (p <0.05) and 12-year-old boys (p <0.01); the cranio-maxillary index Se-N/PNS-A1 was greater in 9-year-old girls (p <0.05), whereas the maxilla-mandibular index PNS-A1/Go-Pg was greater in 9-year-old boys (p <0.01).

CONCLUSION

The findings provided useful reference cephalometric normative measures for the 8-to-12-year-old Southern Italian children population. Significant differences between boys and girls in the length of the anterior cranial base and ratio were reported.

Bridges of the sella turcica - anatomy and topography

This paper presents anatomy and topography of the inconstant osseous bridges that may occur in the sella turcica region. The interclinoid bridge and the caroticoclinoid bridge can be formed in consequence of abnormal ossification of the dural folds or disturbances in development of the sphenoid bone. Their presence may be of clinical importance because of potential influence on the neurovascular structures passing in the vicinity of the clinoid processes of the sphenoid bone.

A reappraisal of the hypophysial region of the floor of the sella turcica

While studying the detailed anatomy of the cranial sella turcica, an additional fossa in its floor, which has not previously been described, was noted. A survey for this fossa, therefore, was conducted on 205 adult crania from the Raymond A. Dart Collection of Human Skeletons, University of the Witwatersrand. To confirm the survey observations, the sella turcica region of 10 adult cadavers was also dissected. A larger anterior depression and a smaller posterior concave fossa, often extending on to the anterior surface of the dorsum sellae, were evident in the hypophysial region and occurred in 21.5% of crania and in six of the 10 dissected specimens. An anterior depression alone or a posterior fossa alone occurred in 2.4% and in 72% of the crania, respectively, indicating that the posterior fossa occurs most commonly in this series. The more commonly occurring presence of a posterior fossa abutting on to the anterior surface of the dorsum sellae is described for the first time.

Palestinians norms of Steiner cephalometric analysis

AIM

To find the cephalometric norms for Palestinian population according to Steiner cephalometric analysis.

METHODS

Lateral cephalograms of 76 dental students (51 females and 25 males, mean age 20.4 ± 2.1 years) were collected from their files at the American University in Jenin, Palestine. They were scanned and analyzed following Steiner measurements. Means and standard deviations for all variables were calculated. Differences between the mean of the variables for both sexes were calculated using the independent t test.

RESULTS

Females had a smaller interincisal angle, more proclined mandibular incisors, and a shorter anterior cranial base than males in the Palestinian population.

CONCLUSION

When the Palestinian sample population was compared to Steiner norms, similar skeletal patterns were found, but the anterior teeth were more proclined and protruded.

Dural suturing for repair of cerebrospinal fluid leak in transnasal transsphenoidal surgery

OBJECTIVE

Repair of a cerebrospinal fluid (CSF) leak after transsphenoidal surgery (TSS) is usually accomplished using various graft materials. These methods are effective in most, but not all, cases.

METHODS

Since 2006, we have been directly suturing the sellar floor dura in patients with an intraoperative CSF leak. Fat and/or fascial grafts were utilized only when a major CSF leak developed. The incidence of postoperative CSF rhinorrhea was compared before and after the suture.

RESULTS

Postoperative CSF rhinorrhea developed in 3.7% (7 out of 188) of cases before 2005, but never since the dural suture was introduced (0 out of 136, 0%; P = 0.0229). Although watertight closure was not achieved in some cases, narrowing the dural defect and supporting the intrasellar graft was attained in every case. Surgical time was approximately 30 min longer in patients who underwent dural suture (148 +/- 42 min) than those who did not (119 +/- 37 min; P = 0.0001).

CONCLUSION

Direct suturing of the sellar dura is a simple, safe, and reliable surgical technique for repairing CSF leaks after TSS. Using this procedure, more than 70% of patients with an intraoperative CSF leak can avoid autologous tissue grafts.

Dimensions, septation, and pattern of pneumatization of the sphenoidal sinus

The endoscopic endonasal transsphenoidal approach (EEA) to treat sellar, parasellar, and suprasellar tumours continues to gain increased significance. Due to the close proximity of the sphenoid sinus to the carotid artery and the optic canal, it is very important for surgeons to know the anatomical features and variations of the sphenoid sinus as relevant to EEA. A prospective study of the sphenoid sinus morphology was carried out on the cranial tomographic (CT) scan images of 60 Nigerian adult patients. The CTs were reviewed regarding the different anatomical variations of the sphenoid sinus: dimensions, septation, and pattern of pneumatisation. There were 37 males and 23 females. The patients' ages ranged from 18 years to 85 years, with a mean of 47.2 years. There was a main single intersphenoid septum in most patients (95%). The insertion of the septum was usually to the right posteriorly (38%) and in the midline anterior (65%). Although there is usually a main septum, the septa present were multiple in 29 of the sinuses studied. There was no gender difference with respect to the attachment of the main sphenoid sinus septum. The sphenoid anterior, posterior, and transverse dimensions were not significantly dependent on age, but they were longer in males than in females. Sellar pneumatization was present in the majority of the patients (83%), with 4 patients having postsellar pneumatization (6.7%) and 3 patients having presellar pneumatization (5%). There were no cases with conchal pneumatization or lateral pneumatization of the greater wing of the sphenoid. The present study provides anatomical information about the sphenoid sinus dimensions morphology that is essential for avoiding complications in performing an endoscopic sphenoidotomy.

Medial wall of the cavernous sinus: microanatomical diaphanoscopic and episcopic investigation

PURPOSE

To elucidate the question whether expansion of pituitary adenomas into the cavernous sinus (CS) has to be regarded as focal penetration rather than invasion, a microanatomical study of the medial wall (MW) of the CS was performed.

METHOD

Fourteen sellar hemiblocks underwent microsurgical dissection from lateral and medial approach. The thickness of the MW of the CS was examined by diaphanoscopy.

FINDINGS

The internal carotid artery (ICA) was adherent to the MW in five cases. In five specimens the lateral wall of the sella turcica consisted of a single layer without perforations. In nine cases this wall had two layers. There was no perforation of both layers in any case. Diaphanoscopy revealed thin MW in the lateral border of the sella (n = 13), below the horizontal segment of the ICA (n = 10), and antero-inferiorly to the carotid syphon (n = 9).

CONCLUSIONS

Expansion into the CS may be facilitated by low anatomical resistance against chronic tumor growth.

Endoscopic endonasal transsphenoidal approach to the sellar region: results of endoscopic dissection on 30 cadavers

AIM

To recognize the endoscopic anatomy of the surgical corridor along the nasal cavity, sphenoidal sinus and the sellar area to delineate the pure endoscopic endonasal transsphenoidal approach (EETSA) to the region of the pituitary gland.

MATERIAL AND METHODS

The endoscopic anatomy of the nasal cavity, sphenoid sinus and the sellar region was studied in 30 fresh cadavers (mean age 42.1 / range 18-66) and dissections were performed in a stepwise manner to simulate EETSA to the sellar region.

RESULTS

The sphenoid ostium, located 14.9 mm superior to the choana, was identified at the midpoint between the nasal septum and the superior turbinate in 23 specimens. The shape of the sphenoid ostium was linear (35%), fusiform (30%), oval(22%) or circular (13%). The mean width of the pituitary gland was 14.3 mm and the average minimum distance between the internal carotid arteries on both sides ranged between 13 to 22 mm. Following total hypophysectomy in 12 specimens, the width and length of diaphragma sellae was measured 10.83 and 5.83 mms respectively.

CONCLUSION

This study documents that variations are common in nasal, sphenoidal and sellar phases of the trans-sphenoidal approach. Detailed knowledge of the basic anatomical relationships through the view of the endoscope and performing endoscopic dissections in large number of specimens will facilitate the endoscopic surgical procedures and decrease the rate of surgical complications.

[Three-dimensional anatomical research on sellar region for transnasal endoscopic surgery]

OBJECTIVE

To develop a new method to explore the three-dimensional characteristics of anatomical structures at the sellar region in transnasal endoscopic surgery.

METHODS

(1) The MicronTracker binocular visual navigation system was modified, and the tool's accuracy was tested by comparing the vernier caliper and turntable. (2) The basis nasi plane and median sagittal plane were used as datum plane, S point (the lateral margin point of nasal spine) and M point (maxillary line midpoint) were used as datum point to orientate the structures. The pitching angle, direction angle and distance of the important structures were measured by the tool designed by us based on the MicronTracker binocular visual navigation system and made a computer graphics model.

RESULTS

(1) The tool's accuracy had no statistical difference as compared with vernier caliper and turntable. (2) The pitching angle, direction angle and distance of the important structures were obtained. (3) 3D-max 9.0 and AutoCAD-2008 were used to set up three-dimensional anatomical model of the anatomical structures.

CONCLUSION

Based on the familiar point and datum of the skull, the orientation data of the important structures could be obtained and the three-dimensional model of the sella region anatomical structures could be constructed.

The implications of microsurgical anatomy for surgical approaches to the sellar region

The knowledge of the normal anatomy and variations regarding the management of tumors of the sellar region is paramount to perform safe surgical procedures. The sellar region is located in the center of the middle cranial fossa; it contains complex anatomical structures, and is the site of various pathological processes: tumor, vascular, developmental, and neuroendocrine. We review the microsurgical anatomy (microscopic and endoscopic) of this region and discuss the surgical nuances regarding this topic, based on anatomical concepts.

Forensic norms of female and male Lebanese adults

Patients born to Lebanese parents and grandparents, visiting two private practice orthodontic clinics, with normal occlusion and no need for any kind of orthodontic treatment during a six month period and satisfying inclusion criteria, were asked permission to include their lateral cephalometric radiographs in this study. Sixty three individuals met the inclusion criteria. Sixteen cephalometric measurements were taken (seven linear and nine angular) were analyzed on each radiograph. Measurements were compared between genders using student's t-test. The study population included 31 females and 32 males with a mean (±SD) of 21.6 (±4.0) and 21.3 (±3.9) years for males and females respectively. Men had significantly larger skeletal linear measurements: the mandibular base menton to gonion (Me-Go) (p=0.027), the total mandibular length of condylon to gnathion (Co-Gn) (p=0.009) and significantly larger angular measurements: sella to nasion to subspinal point (S-N-SS) (p=0.006), and sella to nasion to supramental point (S-N-Spm) (p=0.009). The results of this study demonstrated that male skeletal linear and angular measurements are significantly larger in Lebanese adult males compared to Lebanese adult females.

Facial growth prediction: a comparison of methodologies

INTRODUCTION

The purpose of this study was to compare 3 methodologies that predict facial growth relative to incremental and positional changes over short- and long-term time periods. The 3 prediction systems that were tested and compared were the Ricketts analysis, the Johnston grid analysis, and the Fishman maturational analysis.

METHODS

Serial lateral cephalometric headfilms and hand-wrist films of 50 untreated subjects from the Burlington Growth Center at the University of Toronto, Toronto, Ontario, Canada, were used. The sample was subdivided by skeletal classification and further subdivided by sex. The sample comprised 19 skeletal Class I subjects (10 female, 9 male), 20 Class II subjects (10 female, 10 male), and 11 Class III subjects (6 female, 5 male). Three serial headplates were traced on each subject, and the associated chronologic and maturational ages were noted. The subjects were divided into a young adolescent subgroup approximately 9 years of age (T1), a midadolescent subgroup approximately 13 years of age (T2), and a late adolescent-adult age group approximately 20 years of age (T3). Predictions were made between the time periods. To measure and compare the predicted amounts of downward and forward skeletal growth vs the actual growth values, anatomic landmarks were chosen in the cranial base and on the maxilla and the mandible (Point A and gnathion), and increases between the respective points were measured. A paired t test was applied to each test group for the statistical analysis. Graphic representations were also created in the form of "positional envelopes" that encapsulated the predictive data for each methodology. To evaluate both incremental and positional accuracy, these data envelopes were subsequently related to the true positions of Point A and gnathion.

RESULTS AND CONCLUSIONS

Although not the case in every instance, it was demonstrated that the maturationally oriented Fishman analysis was superior to both the chronologically based Johnston grid and Ricketts analysis for short- and long-term predictions.

The endoscopic endonasal trans-sphenoidal approach to the sellar and suprasellar area. Anatomic study

AIM

The microscopic trans-sphenoidal approach has been the treatment of choice of different sellar lesions over the last thirty years. However, due to several advantages brought by the endoscope, which provides a panoramic and close up view of all the anatomic landmarks either in the sphenoid sinus and in the sellar region, an increasing interest for the trans-sphenoidal approach to the sellar and suprasellar region is being noticed in the recent past years. Since the endoscopic approach drives the surgeon through a corridor whose walls were previously hidden by the nasal speculum, the precise knowledge of the endoscopic anatomy and the anatomical landmarks of the surgical approach are essential to better explore the mentioned advantages.

METHODS

The endoscopic endonasal approach to the sellar region was performed in 40 adult fresh cadavers, with the aim of describing the anatomical landmarks for a safe realization of the surgical approach.

RESULTS

The anatomic features and the variations of the sphenoid ostia, sphenoid sinus and septae, sella turcica, optic and carotid protuberances and their relationships have been described, as well as supra and parasellar neurovascular structures.

CONCLUSION

The endoscopic endonasal trans-sphenoidal approach provides a straight approach to the sellar region, where it offers a multiangled and close-up view of all the relevant neurovascular structures.

Experimental image-guided endoscopic pituitary surgery: a useful learning model

OBJECTIVES

The purpose of this study, which combined image guidance and endocscopic pituitary surgery (EPS), was to test its practicability as a learning tool to acquire the necessary skills in an experimental setting.

METHODS

Ten cadaver-heads were explored using a standard endoscopic transsphenoidal surgical technique combined with the InstaTrak 3500 (GE Medical Systems, Lawrence, MA, USA) image guidance system. The time taken for the experimental setup and the optic-radiologic correlations of topographic landmarks were recorded and photographed.

RESULTS

The average time for setting up the system was 11.9 min+/-2.0, which included head fixation, headset positioning, registration, calibration and verification of the system. With the guidance of the navigation system, the ostium, sellar floor and adjacent structures encountered during EPS could be identified easily and were reflected on the 3D-CT images accurately.

CONCLUSION

The experimental model validated the practicability of image guidance combined with EPS. The non-invasive interactive computer-assisted CT-guided navigational system facilitated the surgical procedure by providing precise spatial relationship between instrument position and adjacent structures. This combination is a useful teaching and learning tool in the cadaver and in patients will be useful, particularly for complex cases and redo-surgery.

Neuronavigational endoscopic endonasal sellar and parasellar surgery using a 2-mm-diameter lens rigid-rod endoscope: a cadaver study

OBJECTIVE

Most of the endoscopes used for endonasal transsphenoidal surgery use 4-mm diameter lenses. The applicability of a newly developed neuroendoscope with a lens diameter of only 2 mm was tested in endonasal transsphenoidal pituitary surgery.

METHODS

The newly developed rigid-rod neuroendoscope with a 2-mm lens and an endoscope with a 4-mm lens were coupled with a navigation system and used for this comparative study. Comparison between the views obtained with these two devices was performed in a model and in formalin-fixed cadaver heads. A pure endonasal approach was used to reach and explore the sellar and parasellar regions. The navigation system was used to locate the same position in both lenses for image comparison.

RESULTS

The sellar and parasellar regions could be reached and explored using the new endoscope with the 2-mm lens and an oval-shaped irrigation and suction channel. The visual field appeared to be reduced compared with that of the 4-mm lens. However, this reduction was compensated by greater mobility and easier introduction and maneuvering of the instruments at the sellar level. Reduced image size and brightness were also found using the 2-mm lens compared with the 4-mm lens. These differences could be overcome by increasing the amount of light and enlarging the image but with subsequent reduction in image resolution.

CONCLUSION

The small diameter of this neuroendoscope resulted in good maneuverability and maintained a fine quality of vision. Children and patients with small nostrils are good candidates for the use of such a device.

Endoscopic anatomy of the parasellar region

BACKGROUND

The aim of this study was to describe the endoscopic anatomy of the cavernous sinus and adjoining parasellar regions and their relationships to the sphenoid sinus.

METHODS

An endoscopic transnasal transsphenoidal approach to the pituitary gland and posterior skull base was performed on three fresh frozen cadaver heads (six sides). Neural and vascular anatomic landmarks of the cavernous sinus and parasellar regions were identified and correlated with sphenoid surface anatomy.

RESULTS

The posterior wall of the sphenoid sinus presents several surface landmarks allowing the identification of the sella, carotid artery, and optic nerve. Identification of the optic-carotid recess allows reflection of the internal carotid artery medially and access to the cavernous sinus. Further lateral dissection allows for easy identification of the oculomotor, trochlear, trigeminal, and abducens nerves. The ophthalmic artery then can be followed from its origin on the internal carotid artery coursing anteriorly into the orbit. The optic chiasm also can be easily identified superiorly. Posteriorly, careful dissection allows access to the basilar artery along the clivus.

CONCLUSION

As endoscopic surgeons continue to expand their procedures to involve areas of the skull base outside the paranasal sinuses, knowledge of the endoscopic anatomy of the sella, parasellar, and adjacent areas is paramount. Critical landmarks are readily evident in the sphenoid sinus providing good access to neural and vascular structures of this region of the skull base.

Surgical anatomy of the petrous apex and petroclival region

Surgical exposure of the clivus, the ventral or lateral aspect of the brain stem, and all the intradural structures of the petroclival area remains difficult because of the presence of the petrous apex and peripetrous complex. However, a lateral skull base approach to the petroclival area is the most suitable approach if the lesion to be resected lies medial to the fifth nerve, in front of the acousticofacial bundles, extending towards the midline. The purpose of this study is to review the topographic anatomy of the petrous apex and peripetrous structures, with emphasis on the relationships important to the lateral approaches to the petroclival area. Such anatomical knowledge allows us to study the surgical technique, exposure, and pitfalls of the main lateral transpetrosal skull base approaches used to reach the petroclival area.

Linear and angular filipino cephalometric norms according to age and sex

OBJECTIVE

To quantify relevant cephalometric parameters for Filipinos according to age and sex.

MATERIALS AND METHODS

A total of 157 Filipino subjects (78 males, 79 females) who fulfilled specific criteria were selected from elementary, high school, and college students affiliated with Manila Central University. They were divided into comparison groups (GI, GII, GIII, and GIV) on the basis of chronological age and sex. Lateral cephalograms were taken for all subjects, and the mean and standard deviation for each parameter was recorded and compared among groups.

RESULTS

The male group had a longer anterior cranial base (S-N), total facial height (N-Me), longer lower anterior facial height (N-ANS), longer ramus height (Cd-Go), longer lower posterior dentoalveolar height (Mo-Mi'), and total mandibular length (Gn-Cd) than the female group. All these linear measurements were statistically significantly different between males and females in GI, GIII, and GIV. On the other hand, SNB angle showed significant differences (P = .0271) in GIV only. In the lower third of the face, significant opposite tendencies were found in GIV. The female group showed a clockwise rotation, whereas the male counterpart had a counterclockwise rotation of the mandibular plane. The denture pattern of both groups was characterized by a proclination of both lower incisor (Ii to MP) and upper incisor (Is to SN).

CONCLUSIONS

Convexity due to dentoalveolar protrusion is the naturally occurring facial profile for Filipinos. The adult females showed steeper mandibular and occlusal plane angles than the male samples.

The "yo-yo" technique to prevent cerebrospinal fluid rhinorrhea after anterior clinoidectomy for proximal internal carotid artery aneurysms

OBJECTIVE

Resection of the anterior clinoid process is important for the exposure of aneurysms on clinoidal and supraclinoidal segments of the internal carotid artery. Cerebrospinal fluid (CSF) rhinorrhea can complicate anterior clinoidectomy when the optic strut is pneumatized and its removal communicates the subarachnoid space with the sphenoid sinus. We present a technique for repairing this defect and preventing CSF rhinorrhea.

METHODS

A suture is secured around a strip of temporalis muscle, which is then pushed through the opening in the optic strut completely into the sphenoid sinus. The ends of suture that trail the muscle are used to retract the muscle from the sphenoid sinus back into the optic strut. The suture is trimmed and the repair is covered with sealant or fibrin glue.

RESULTS

During an 8-year period in which 127 patients with proximal internal carotid artery aneurysms that required anterior clinoidectomy were treated, pneumatized optic struts were encountered in 14 patients (11%). Four patients were treated with the "yo-yo" technique, none of whom experienced CSF rhinorrhea. Before using this technique, 10 patients were managed with standard packing techniques (wax, muscle, and gel foam) and four of these patients subsequently experienced CSF rhinorrhea (40%). In these four patients, all required reoperation with either craniotomy and packing with pericranium (one patient), Couldwell-Luc procedure (one patient), or endoscopic transnasal obliteration of the sphenoid sinus with fat (two patients).

CONCLUSION

The "yo-yo" technique of tightly wedging a muscle plug into the optic strut proved to be simple, fast, and effective, preventing CSF rhinorrhea in all patients in whom it was applied. Although experience with this technique is limited, reversing the direction of packing and pulling muscle from the sphenoid sinus into the optic strut eliminated a complication that occurred in 40% of patients with standard packing techniques.

Speculum opening in transsphenoidal surgery

OBJECTIVE

To assess the extent to which the transsphenoidal speculum can be safely opened at the face of and within the sphenoid sinus without risking damage to the optic nerves in the optic canals and at the orbital apex and the nerves coursing adjacent the walls of the sphenoid sinus.

METHODS

The distance was measured between the optic nerves at the level of the anterior wall of the sphenoid sinus and 0.5 and 1.0 cm within the sinus. In addition, the distance between the middle turbinates and the contralateral optic canals was assessed because this turbinate is the largest structure blocking access to the sphenoid sinus in the transsphenoidal approach and tends to force the speculum away from the midline and toward the optic nerve in the contralateral side of the approach.

RESULTS

Opening the transsphenoidal speculum at the anterior wall of the sphenoid sinus beyond 2.5 centimeters carries some risk of damaging the optic nerves and this distance narrows when the speculum opening is positioned inside the sphenoid sinus. Displacement of the speculum to one side by the middle turbinate places the speculum near the contralateral optic nerve and may be associated with optic nerve injury with lesser degrees of speculum opening.

CONCLUSIONS

Careful attention should be directed to avoiding excessive opening of the transsphenoidal speculum at the anterior face of the sphenoid or within the sphenoid sinus.

The endoscopic extended transsphenoidal approach for craniopharyngiomas

OBJECTIVE

The endoscope has recently been applied to the supradiaphragmatic transsphenoidal approach, but only case reports dealing with different pathological features have been described. The authors present their experience with this technique in 10 patients with craniopharyngiomas.

METHODS

A pure endoscopic endonasal technique was used. From November 1998 through May 2005, four males and six females with a craniopharyngioma, either purely supradiaphragmatic (six patients) or with a significant suprasellar component (four patients), were treated. The tumors had a mean diameter of 2.9 cm (range, 1-4 cm); four patients had a major prechiasmatic component and six had a retrochiasmatic one.

RESULTS

Seven total, one subtotal, and two partial resections were obtained. Vision symptoms improved significantly in six out of eight patients. Endocrine function did not improve after surgery, and diabetes insipidus was the most frequent deficit, although it was transient in five out of eight patients. Cerebrospinal fluid leak was the most frequent complication and required reoperation in two patients. Postoperative obesity occurred in two patients. No recurrence has yet been documented in the total resection group. The mean follow-up period is 37 months (range, 3-75 mo).

CONCLUSION

The endoscopic technique allows results comparable with the best microscopic series. We think that this technique increases the safety of the procedure because of improved vision. Further studies are required to better define the exact location of the tumor with respect to the arachnoidal plane, the extra-arachnoidal craniopharyngioma being the most suitable for a radical removal using a transsphenoidal supradiaphragmatic approach.

Validity and reliability of a new edge-based computerized method for identification of cephalometric landmarks

OBJECTIVE

To evaluate the validity and inter- and intraexaminer reliability when on-screen landmarks are digitized manually or when these are computer-assisted by means of a new cephalometric software feature.

MATERIALS AND METHODS

Twenty radiographs were digitized four times by two experienced orthodontists using a manual method and an edge-based algorithm that helps landmark identification by detecting the edges of anatomical structures.

RESULTS

The computer-assisted method did not agree with manual digitization in 7 of 13 landmarks and 5 of 10 variables. With a tolerance of 0.5 mm or degrees, the two methods did not agree in cephalometric variables. Intraoperator reliability was improved for B point (x-axis), and Menton (x- and y-axis). It got worse for point A (y-axis). Interoperator reliability was improved for B point (x- and y-axis), Soft Labrale Inferior (x- and y-axis), Soft Pogonion (x-axis), and Menton (y-axis). It decreased for point A (y-axis). Intra- and interoperator reliability got better for only one cephalometric variable under study (SNB).

CONCLUSIONS

The edge-locking feature seems to be a promising tool for increasing the reliability of on-screen cephalometric analysis. There seem to be difficulties in locating the appropriate edges when artifacts or soft tissue edges are located near the targeted landmark. The existence of very small, but systematic differences between the two digitization methods manifests the need for further improvement.

Sellar floor reconstruction after transsphenoidal surgery using fibrin glue without grafting or implants: technical note

BACKGROUND

Different techniques have already been described for reconstructing the sellar floor after transsphenoidal (TS) procedures. This paper reports on the use of fibrin glue alone without grafting or the use of implants in the reconstruction of the sellar floor after TS.

METHODS

Five hundred sixty-seven patients who submitted to TS for pituitary and sellar region tumors were studied. No intraoperative cerebrospinal fluid (CSF) leak occurred in 503 patients (group 1); in the remaining 64 patients (group 2), intraoperative CSF leak was noted. In group 1 patients, closure of the sellar floor consisted of packing the surgical bed with hemostatic material only. When CSF leak was noted, the surgical bed was covered with a layer of hemostatic material and the intrasellar space was filled up with fibrin glue. An additional layer of hemostatic material was added at the topography of the preexisting sellar floor, and a second amount of fibrin glue was applied over it. At the end of surgery, a continuous lumbar CSF drainage system was installed in group 2 patients and kept for 5 days. Prophylactic antibiotics were administered during this period.

RESULTS

We did not observe delayed CSF leak, meningitis, or visual loss in group 1 patients. In group 2, 2 patients presented with complications: 1 patient got meningitis but no overt CSF leak, and the other disclosed a delayed postoperative leak treated by reoperation.

DISCUSSION

Our results showed that closure of the sellar floor with hemostatic material and fibrin glue without grafting or the use of implants is a safe and efficient method to prevent postoperative complications after TS. Generally speaking, there is no need for grafting or the use of implants at the end of TS.

Eyebrow Surgery: The Supraciliary Craniotomy: Technical Note

OBJECTIVE:

Many approaches have been recommended for the surgical treatment of anterior and middle cranial fossa lesions. The frontobasal approach and its many modifications have been proposed and developed for such situated lesions. An alternative approach is the frontolateral craniotomy through a supraciliary skin incision.

METHODS:

This minimally invasive technique, a 2.5 × 3.0 cm craniotomy, just above the eyebrow through a supraciliary incision, is a simple but elegant modification of the traditional approach to the anterior cranial fossa.

RESULTS:

A step-by-step description of the approach is offered in this report to facilitate a clear understanding of the lesions treatable with this minimally invasive technique.

CONCLUSION:

The supraciliary frontolateral keyhole craniotomy is a minimally invasive cosmetic approach that provides excellent exposure to a variety of intracranial lesions. This approach cannot be used for all intracranial pathologies, but is recommended for many anterior and middle cranial fossa lesions.

A prospective analysis of 151 cases of patients with acromegaly operated by one neurosurgeon: a follow-up of more than 23 years

BACKGROUND

Transsphenoidal adenomectomy has been the accepted surgical management for treatment of growth hormone (GH)-secreting pituitary adenomas. Although the goal of treatment might be to keep the GH level in the reference range, the actual definition of success in control of acromegaly is not yet clear.

METHODS

The aim of this study was to analyze prospectively the result of transsphenoidal adenoctomy performed over 23-year period by a single neurosurgeon in one center. The analysis has been performed to determine which preoperative factor could significantly influence the long term outcome. This series consisted of 151 patients. The preoperative hormonal studies documenting the high GH and/or insulin-like growth factor were available in all the cases. At least 1 laboratory report documenting the postoperative level of hormones was also available for all of them. Transsphenoidal microsurgical adenomectomy was performed in all the cases.

RESULTS

There were 90 patients with pure GH-secreting adenoma (59.6%) with the highest GH level of 235 mU/L. A second group of 12 patients had normal GH level but elevated serum level of insulin-like growth factor 1 (8%). The group with mixed secretion of GH and prolactin included 49 cases (32.4%). There was no postoperative mortality. Cerebrospinal fluid leakage occurred in 12 patients. Transient diabetes insipidus was encountered in 19 cases (12.6%) and long lasting diabetes insipidus in 2 patients (1.3%). Early and minor hypopituitarism was encountered in 14 patients, whereas a persistent condition occurred mainly after irradiation in 14 other cases. Normal postoperative serum GH level could be achieved in 98 patients (94.2%) of 104 cases with full follow-up.

CONCLUSION

In the developing countries, early diagnosis and proper surgical extirpation of the GH-secreting adenoma by an experienced and dedicated pituitary surgeon is mandatory to reduce the mortality and increase the chance of cure of this rather mortal endocrionopathy.

A Surgical Technique for the Removal of Clinoidal Meningiomas

CLINOIDAL MENINGIOMAS, ALSO referred to as medial or inner sphenoid wing meningiomas, are often difficult and challenging to remove completely and safely, especially when they become large enough to encircle, compress, or displace the adjacent critical neurovascular structures such as the optic nerve, the internal carotid artery and its branches, and the oculomotor nerve. In this article, the authors describe the detailed surgical technique used in their practice in addition to subtle nuances learned from their experience of operating on more than 40 patients with clinoidal meningiomas over the past several years. The primary goals of surgery are to achieve aggressive tumor removal with avoidance of intraoperative morbidity and, in addition, for those with preoperative compromised vision, to provide improvement in their visual function after surgery.

Endoscopic Pituitary Surgery

Endoscopic pituitary surgery has definite advantages over the traditional method using the operating microscope. Improved visualization, angled view, and a wider panoramic perspective of the important anatomic relationships of the sphenoid and the sella turcica were the obvious advantages. The direct endonasal transsphenoidal approach is the most minimally invasive. Its advantages include wider access, avoidance of a septoplasty, and the ability for two surgeons to work together enabling better instrumentation and more complete and rapid removal of the tumor.

Natural head position and inclination of craniofacial planes

PURPOSE

To assess the angles between craniofacial planes and the gravity horizontal plane (GHP).

MATERIALS AND METHODS

The plumb line was hung from the ceiling, the Fox plane (FoxP) was placed in the mouth, and 56 Angle Class I subjects were photographed in a natural head position. FoxP represents the extraoral view of the occlusal plane.

RESULTS

In frontal view, bipupilar plane (BP) and occlusal plane (FoxP) were almost parallel to GHP. In lateral view, FoxP was almost parallel to GHP, but Frankfort horizontal plane (FHP) and Camper's plane (CP) were not. FoxP and CP were not parallel.

CONCLUSION

CP is not a reliable landmark for occlusal plane reconstruction. FHP does not represent GHP.

Endonasal transsphenoidal surgery: the patient's perspective—survey results from 259 patients

BACKGROUND

Patient impressions remain an important yet often overlooked aspect of surgical success. Herein we present postoperative questionnaire results in patients after a standard direct endonasal approach, an extended suprasellar endonasal approach, and a reoperative transsphenoidal surgery for tumor removal with the operating microscope.

METHODS

From July 1998 through April 2005, of 452 patients undergoing endonasal surgery, 346 were sent questionnaires, and of these, 259 (75%) completed them. Nasal packing was placed for 24 hours in the first 95 patients but not in the last 357.

RESULT

Overall, 73% of patients reported a better experience than expected and 8% worse than expected. A worse than expected overall experience was noted in 15% of patients with nasal packing compared with 5% of patients without packing (P = .001). Of patients with preoperative headache, 49% resolved, 34% somewhat resolved, and 5% worsened. The frequency of rhinological complaints declined from 2 weeks to 3 months postsurgery (P < .001); by 3 months or more postsurgery, 67% to 87% of patients had no rhinological complaints and 1% to 2% had severe complaints. Of 30 patients with prior sublabial surgery, the endonasal procedure afforded easier recovery (87%), less pain (80%), better nasal airflow (79%), and a shorter hospital stay (median 3 vs 5 days) (P < .001). Of 28 patients with complications, the severity of rhinological complaints was similar to those without complications except this subgroup reported greater loss of sense of smell 3 months after surgery (P < .001).

CONCLUSIONS

Rhinological recovery is typically rapid and relatively complete after direct endonasal transsphenoidal surgery using both standard and extended suprasellar approaches. Compared with the sublabial route, the endonasal approach is associated with less pain, better nasal airflow, and a shorter hospital stay.

T1 signal hyperintensity in the sellar region: spectrum of findings

T1 signal hyperintensity is a common finding at magnetic resonance imaging of the sellar region. However, this signal intensity pattern has different sources, and its significance depends on the clinical context. Normal variations in sellar T1 signal hyperintensity are related to vasopressin storage in the neurohypophysis, the presence of bone marrow in normal and variant anatomic structures, hyperactive hormone secretion in the anterior pituitary lobe (eg, in newborns and pregnant or lactating women), and flow artifacts and magnetic susceptibility effects. Pathologic variations in T1 signal hyperintensity may be related to clotting of blood (in hemorrhagic pituitary adenoma, pituitary apoplexy, Sheehan syndrome, or thrombosed aneurysm) or the presence of a high concentration of protein (Rathke cleft cyst, craniopharyngioma, or mucocele), fat (lipoma, dermoid cyst, lipomatous meningioma), calcification (craniopharyngioma, chondroma, chordoma), or a paramagnetic substance (manganese, melanin). After treatment, T1 signal hyperintensity may result from the presence of materials used for surgical packing (gelatin sponge, fat); from compression of the cavernous sinus and reduction of the venous flow, caused by overpacking of the operative bed; or from hormone hypersecretion by a remnant of normal tissue in the anterior lobe of the pituitary gland.

The incidence and types of sella and sphenopetrous bridges

The incidence and types of sella and sphenopetrous bridges were investigated in 37 adult male and 43 adult female (a total of 80) dry skulls with removed calvarias. In addition to this, the sellar and parasellar region of ten fixed cadavers (two female and eight male) were carefully dissected, and the individuals were examined for the evidence of sella and sphenopetrous bridges. Sella bridges were seen in 34.17% of the subjects overall. The trace, incomplete and complete types were 11.9%, 3.7% and 17.5%, respectively. On the other hand, sphenopetrous bridges were observed in 15.8% of the male and 4.9% of the female subjects overall. The cadaveric investigation revealed one trace, three incomplete, and one complete sella bridge in three cadavers. In addition to this, a complete sphenopetrous bridge was detected in one of the cadavers. Variations in the cranial base are of importance for surgical approaches in that location.

[The use of TachoComb for the rhinorrhea repair in pituitary transsphenoidal surgery]

The transsphenoidal pituitary tumors surgery is often connected with intraoperative rhinorrhea. This complication might be serious if occurs again in the postoperative period. The aim of this study is to evaluate the sella reconstruction methods in patients with intraoperative rhinorrhea and comparing of their efficiency.

MATERIAL AND METHODS

In the group of 259 consecutive cases operated on at the Neurosurgery Department in Cracow using the transsphenoidal approach, in 40 occured intraoperatively observed rhinorrhea. In the 26 cases we used Surgicel, artificial dura or fascia and Tissucol (I group), and in 14 TachoComb with Tissucol but in 5 also fascia or artificial dura (II group).

RESULTS

Out of the 26 patients from the I group (without TachoComb) in 5 cases occurred postoperatively rhinorrhea (3-36 days after surgery). 4 patients were reoperated, 1 patient died due to the meningitis. 2 patients suffered from the visual disturbances due to the sella overpacking (7,7%), what was visualized in the control imaging studies. In 14 cases from the II group in 2 postoperative rhinorrhea was observed (in the 7 and the 30 day after operation)--14,2%. There were no signs of meningitis, and no fatal cases. The visual disturbances as well as overpacking of the sella were not observed.

CONCLUSIONS

Using of the TachoComb in reconstructive surgery of the sella reduces the risk of the post operative CSF leak and eliminates the features of the sella overpacking and visual deterioration.

Medial portion of the cavernous sinus: quantitative analysis of the medial wall

Pituitary tumors invade the cavernous sinus via the medial wall. Researchers have speculated that this wall is composed of dura and that substances secreted by tumors might damage this barrier. In contrast to the lateral wall, little is known about the structure of the medial wall of the cavernous sinus (MWCS). This study provides the first detailed quantitative (thickness) and qualitative (histological) assessment of the MWCS. Eighteen sellar-parasellar tissue blocks were obtained from adult human autopsies. Ten specimens were used for microsurgical dissection and macroscopic anatomical description. Eight specimens were used for histopathological study and for recording computer measurements of MWCS thickness. Each of these eight specimens was divided into three approximately equal-sized pieces, with cuts made in the coronal plane from posterior to anterior starting at the anterior level of the pituitary stalk. Wall thicknesses were compared in the three different regions (posterior, middle, anterior), and also on the left vs. the right sides. The investigations showed that the MWCS is a distinct dural layer that forms a barrier between the medial venous space of the cavernous sinus and the pituitary gland. The mean thickness of the 48 total (left and right) MWCS observed in the 24 sections examined was 0.195 +/- 0.066 mm (range = 0.080-0.387 mm). This wall is composed of loosely arranged collagen fibers that comprise a specific layer known as "meningeal dura." The posterior third of the MWCS was significantly thinner than the middle third (P = 0.0014) or anterior third (P = 0.0001). No macro- or microscopic defects were observed in any of the MWCS in the 18 specimens. The thinness of the posterior MWCS suggests that this is the most likely path for extension of pituitary tumors into the cavernous sinus.

A new morphometric method for the sella turcica and the hypophyseal fossa and its clinical relevance

The sella turcica and the hypophyseal fossa should be considered different entities, the latter being part of the former. Their morphology and dimensions correlate to some extent with those of the contained pituitary gland and have, for this reason, attracted the interest of anatomists and radiologists. With the application of MRI, however, these data are of limited use in the diagnosis of pituitary disorders, although they remain valuable with regard to a microsurgical approach to the hypophysis. The proposed morphometric method was applied to 20 dry skulls. We first made casts of the corresponding sellae. Their volumes were then measured by immersion. The frontal section of each hypophyseal fossa was obtained through its deepest point and magnified. The Cartesian co-ordinates of the contour of the section were used to evaluate the corresponding area and centroid. The volume of each fossa was finally obtained by the use of Pappus' theorem applied to solids of rotation. The volumes of the sellae obtained as above ranged from 460 mm3 to 1570 mm3 with a mean value of 835 mm3. These figures are comparable to those reported from previous authors. To our knowledge the method described has enabled a close approximation of the volumes of the hypophyseal fossae to be made for the first time. These volumes ranged from 24 mm3 to 300 mm3, with a mean value of 157 mm3. Similar numerical methods might be applicable in vivo by the use of MR imaging.