Subarachnoid haemorrhage is a critical neurological emergency marked by the escape of blood into the space between the pia mater and the arachnoid layer. This condition carries a high mortality rate and those who do survive frequently face notable neurological impairments.

The main cause of nontraumatic subarachnoid hemorrhage (SAH) is generally due to the bursting of saccular aneurysms. SAH often results in disastrous consequences, leading to elevated death rates and serious health issues for those who recover. The selection of treatment for SAH depends on the severity of the haemorrhage. Upon arrival, the most important predictive factors for subarachnoid haemorrhage (SAH) are the consciousness level at admission, the patient's age, and the amount of blood visible on the initial head CT scan ⁽¹⁾. 

Although traumatic brain injury is the leading cause of subarachnoid hemorrhage (SAH), there are also multiple non-traumatic reasons for this condition. CT Angiography presents an up-and-coming imaging method for screening or pre-procedural use. It provides several benefits, such as being non-invasive, having a low complication risk, being quicker and easier to conduct, requiring fewer resources, being more comfortable for patients, and being appropriate for unstable or critically ill individuals.

Once a case of subarachnoid haemorrhage (SAH) is identified, it is essential to determine the source of the bleeding through angiographic evaluations. We prefer conventional digital subtraction angiography (DSA) due to its enhanced resolution in identifying aneurysms and its capability to facilitate endovascular treatments during the same procedure. However, some facilities utilise noninvasive imaging modalities like computed tomography angiography (CTA) or magnetic resonance angiography (MRA) as the initial assessment, reserving DSA for cases where noninvasive imaging does not reveal the cause of the SAH ⁽²⁾.

CTA presents a significant benefit over DSA due to its quick and straightforward availability, often accessible right after confirming an SAH diagnosis with a head CT while the patient is still in the scanner. CTA is increasingly being used as an alternative to DSA for many patients with SAH, thereby eliminating the need for DSA in some situations during the pre-interventional treatment phase. In acute scenarios where a patient is rapidly declining and requires an urgent craniotomy to address a hematoma, CTA is particularly useful. Furthermore, CTA offers a more practical approach to diagnosing urgent conditions than MRA, given the challenges of managing acute cases. DSA becomes necessary when CTA does not identify the source of bleeding and is usually required following CTA. Where feasible, endovascular techniques are generally employed as the first option for treatment ⁽³⁾. 

AIM: To analyse the findings of non-traumatic subarachnoid haemorrhage on multislice Multi-Detector Computed Tomography Angiography (CTA).

OBJECTIVES:

• To determine the various causes of non-traumatic subarachnoid haemorrhage with the help of multislice MDCT angiography.
• To assess the location and size of the underlying causes for non-traumatic Subarachnoid Hemorrhage with the help of multislice MDCT angiography.

Study Design: A prospective hospital-based observational study.

Study area: Department of Radio Diagnosis, Karuna Medical College, Chittor, Palakkad.

Study Period: 1 year.

Study population:  

• Patients who get referred to the department of Radio-diagnosis, with clinically suspected non-traumatic subarachnoid haemorrhage, for computed tomography of the brain.
• Patients with incidental subarachnoid haemorrhage findings on CT scan of the brain or MRI brain from the Inpatient and outpatient departments were studied on multislice GE CT scanners.

Sample size: The study consisted of 40 subjects.

Sampling method: Simple random technique.

Inclusion criteria:

• Patients who are clinically suspected of having a nontraumatic subarachnoid hemorrhage.
• Subarachnoid haemorrhage found incidentally on CT scan of the brain or MRI of the brain.

Exclusion Criteria:

• Absolute Contraindication for contrast agent.
• Recent surgical intervention.
• Bleeding tendency like Haemophilia.
• Sensitivity to intravenous contrast media.
• Poor general condition.
• Patients who are not willing to get the study.
• Pregnant patients.

Ethical consideration: Institutional Ethical committee permission was taken before the commencement of the study.

Study tools and Data collection procedure:

• CT angiography was performed in multislice Multidetector Computed tomography (SIEMENS SOMATOM) for all patients who met the inclusion criteria.
• Based on the requirement, the following sequences will be performed: NCCT, Sagittal CECT angiography image, Axial CECT angiography image, Coronal CECT angiography image, Maximum Intensity Projection images of CT Angiography, and Volume Rendering.

All the acquired images will be transferred to a GE AW VOLUMESHARE 5 workstation and multiplanar reconstruction will be performed.

Statistical analysis:

In the present study, descriptive statistical analysis was performed. Results for categorical measurements are reported in Number (%), whereas results for continuous measurements are reported as Mean ±SD(Min-Max). Significance is evaluated at a 5% level of significance.

Table 1: Age group

The table presents age group distribution, indicating a predominant presence of individuals aged between 41 to 50, constituting 40% of the total count. Those aged 51 to 60 follow, representing 30% of the total count. The data suggests a relatively balanced distribution among middle-aged groups, with a decline in representation in both younger and older age groups.

The frequency distribution of sexes showcases an equal split between males and females, each constituting 50% of the total count.

Table 2: Complaints

The table illustrates the frequency distribution of various chief complaints in a dataset. "Headache" emerges as the most prevalent complaint, constituting 42.5% of the total count, followed by "Headache and Giddiness" at 15.0%.

The frequency distribution of diagnoses resulting from CT Angiography. Among the diagnoses, "Aneurysm" emerges as the predominant finding, representing 80.0% of the total count. "AVM" (Arteriovenous Malformation) constitutes the remaining 20.0%.

Table 3: Site of lesion

The table presents the frequency distribution of lesion sites based on medical imaging findings. The most prevalent site is the Anterior Communicating Artery (ACOM), accounting for 35% of cases, followed by other sites with lower frequencies.

Noteworthy findings include the presence of AVMs (Arteriovenous Malformations) in different regions such as the frontal, parietal, and temporal lobes, each contributing 2.5% to the total count. Additionally, specific arteries like the Basilar artery and segments of the Middle Cerebral Artery (MCA) and Anterior Cerebral Artery (ACA) are identified in the dataset.

The frequency distribution regarding the presence of aneurysms. Among the cases examined, 80.0% demonstrate the presence of aneurysms, while 20.0% indicate their absence. This suggests a significant prevalence of aneurysms within the dataset.

The frequency distribution of the number of aneurysms present within the dataset. The majority of cases (75.0%) exhibit a single aneurysm, while a smaller proportion (2.5%) have either two or three aneurysms. Additionally, 20.0% of cases show no presence of aneurysms.

Table 4: Aneurysms site

The table presents the distribution of aneurysms across various sites. The most common site is the Anterior Communicating Artery (ACOM), comprising 45.71% of cases, followed by the Right Middle Cerebral Artery (MCA) with 11.4%. Other sites represent smaller proportions.

The frequency distribution of aneurysm distribution across different circulatory regions. A significant majority of cases (80%) exhibit aneurysms in the Anterior Circulation, while a smaller proportion (20%%) are located in the Posterior Circulation.

Table 5: Size and aspect ratio of aneurysm

The descriptive statistics reveal key insights into three variables related to aneurysms. Firstly, the size of the aneurysm, with a mean diameter of 4.39 millimetres and a standard deviation of 2.363, indicates a moderate variability in aneurysm sizes within the dataset, ranging from a minimum of 1.400 mm to a maximum of 13.30 mm. Secondly, the size of the neck in aneurysms shows a mean of 2.87 mm, with a standard deviation of 0.933, suggesting a narrower range compared to the aneurysm size itself, ranging from 1.000 mm to 4.90 mm. Lastly, the aspect ratio of aneurysms exhibits a mean of 1.67, implying a moderately elongated shape on average, with a standard deviation of 0.893, indicating variability in aneurysm shapes, ranging from 0.538 to 3.53.

Table 6: Classification of aneurysm (mm)

The table provides a breakdown of the classification of aneurysms based on their sizes in millimetres. Notably, the majority of aneurysms fall within the size range of less than 3 millimetres, constituting 40.0% of the total count. A significant proportion, 31.4%, falls within the size range of 3 to 5 millimetres. Additionally, 25.7% of aneurysms are classified within the range of 5 to 12 millimetres. Interestingly, only one aneurysm, accounting for 2.9% of the total count, falls within the larger size range of 13 to 24 millimetres.

The frequency distribution of aneurysm aspect ratios is categorized into two classifications: those with an aspect ratio less than 1.3 and those greater than or equal to 1.3. The majority, comprising 60.0% of the total count, fall into the category of an aspect ratio greater than or equal to 1.3. Conversely, 40.0% of aneurysms have an aspect ratio of less than 1.3.

The frequency distribution of aneurysm shapes is categorized into three types: Irregular, and Saccular. The vast majority, comprising 97.14% of the total count, are classified as Saccular aneurysms, representing the predominant shape within the dataset. Additionally, 2.85% Irregular aneurysms, albeit with minimal representation.

The frequency distribution regarding the presence of AVM. Among the cases examined, 20.0% demonstrate the presence of AVMs, while 80.0% indicate their absence. This suggests a lower prevalence of AVMs within the dataset. 

Table 7: Site of AVM

The table illustrates the frequency distribution of arteriovenous malformation (AVM) sites within the dataset. Each site of AVM occurrence is represented equally, with 12.5% of the total count attributed to each site. These sites include the Left Frontal Lobe, Left Parasagittal Frontal Lobe, Left Parietal Lobe, Left High Frontal Lobe, Parafalcine Region of Left Frontal Lobe, Right Frontal Lobe, Right Temporal Lobe, and Suprasellar region.

Table 8: Size of Nidus (cm)

The table presents the frequency distribution of the size of nidus (the core or centre) in centimetres for arteriovenous malformations (AVMs). Each size category is represented by one occurrence, contributing equally to 12.5% of the total count. The sizes range from 0.8 cm to 2.1 cm, with varying increments such as 0.9 cm, 1.2 cm, 1.5 cm, 1.6 cm, 1 cm, and 6 mm.

The frequency distribution of the involvement of eloquent areas in arteriovenous malformations (AVMs), is categorized as either "Yes" or "No". Remarkably, all cases (100.0% of the total count) exhibit no involvement of eloquent areas.

The frequency distribution of venous drainage patterns associated with arteriovenous malformations (AVMs), categorized as either "Deep" or "Superficial". The majority of cases (87.5% of the total count) exhibit superficial venous drainage, while only one case (12.5%) demonstrates deep venous drainage.

Table 9: Spetzler Martin grading

The table displays the frequency distribution of Spetzler-Martin grading for arteriovenous malformations (AVMs). The majority of cases (87.5% of the total count) are classified as Grade 1, indicating smaller AVMs with favourable characteristics for surgical intervention. Conversely, only one case (12.5%) falls into Grade 2, suggesting larger AVMs with more complex features that may have challenges for surgical treatment.

Figure 1: NCCT: Axial (A), Sagittal (B), Coronal (C) shows linear sulcal hyperdensities in bilateral frontal, parietal and temporal lobes which is suggestive of Sub-arachnoid hemorrhage.

Figure 2: CT Angio: Maximum intensity projection (MIP) images: Axial (A), Sagittal (B), and Coronal (C) show a well-defined saccular outpouching in the region of the anterior communicating artery. Corresponding VR image (D) showing ACOM aneurysm. The ancillary finding includes the dolichoectasia of the vertebrobasilar system (E).

Figure 3: NCCT Axial (A), Sagittal (B), Coronal (C) NCCT images show linear sulcal hyperdensities in bilateral sylvian fissures and suprasellar cistern which is suggestive of Sub-arachnoid hemorrhage.

Figure 4: CT Angio: MIP images: Axial (A), Sagittal (B), Coronal (C) show a well-defined broad-based saccular outpouching in the region of the anterior communicating artery. Corresponding VR image (D) showing ACOM aneurysm. In the same case MIP Images Axial (E), Sagittal (F), and Coronal (G) show a tiny saccular outpouching in the region of the basilar artery tip. The corresponding VR image (H) shows a tiny aneurysm in the basilar artery tip.

Figure 5: NCCT Axial (A), Sagittal (B), and Coronal (C) images show linear sulcal hyperdensities in bilateral frontal, parietal, temporal region and bilateral sylvian fissures which is suggestive of SAH. Post-contrast VR image (D) shows multiple aneurysms in ACOM, right and left MCA.

Figure 6: CT Angio: MIP images Axial (A, B) shows a nidus in the left frontal lobe (A, B) with feeding artery left ACA (A) and draining vein into an internal cerebral vein (A, B). Corresponding VR image (C) shows a nidus in the left frontal lobe, feeding artery left ACA and draining vein into an internal cerebral vein.

FIGURE 7: NCCT Axial (A, B) shows linear hyperdensities of HU +60 to +70 in bilateral sylvian fissures, fourth ventricle which is suggestive of SAH. CT Angio (C) and VR reconstructed image (D) show an aneurysm in the left PICA.

Non-traumatic subarachnoid hemorrhage (SAH) typically results from the rupture of an intracranial aneurysm, a condition that poses a significant risk of serious illness or death if not correctly diagnosed. SAH resulting from an aneurysm rupture has a considerable potential for fatality and disability, constituting roughly 25% of deaths related to cerebrovascular incidents. Even with improvements in the management of SAH, the mortality rates still range from 25% to 50%. Additionally, around half of those who survive experience disabilities that necessitate help with everyday activities.

The critical link between intracranial aneurysms and SAH underscores the urgency for accurate diagnosis and effective intervention strategies. Improved diagnostic tools like multislice MD CT angiography offer enhanced precision in identifying aneurysms and assessing their potential for rupture. Addressing the challenges of misdiagnosis and early intervention can significantly affect patient outcomes, reducing mortality rates and improving the quality of life for SAH survivors ⁽⁴⁾. 

Conducting a computed tomography angiography (CTA) in SAH patients serves multiple purposes, including identifying the precise origin of vascular damage, evaluating blood vessel morphology to gauge risk levels, and formulating an appropriate treatment approach. This imaging modality aids in pinpointing the specific vascular source contributing to the SAH, allowing for a comprehensive understanding of the underlying pathology. By assessing the structure and integrity of blood vessels, clinicians can stratify patients based on their risk profiles, guiding decisions on therapeutic interventions and management strategies. The utilization of CTA in SAH care enhances diagnostic accuracy, facilitates personalized treatment plans, and improves patient outcomes by addressing the intricacies of cerebrovascular pathology.

Intracranial computed tomography angiography (CTA) has evolved into a cornerstone technique for assessing SAH patients before initiating treatment. The continuous development of multislice CT technology has spurred exploration into various iterations, such as 16-slice CTA and 64-slice CTA, aimed at improving the detection, characterization, and evaluation of intracranial aneurysms. Moreover, advanced methodologies like bone-removal dual-energy CTA and higher detector row configurations such as 128, 256, and 320 have been extensively researched. These cutting-edge advancements are designed to enhance the precision and reliability of detecting intracranial aneurysms, ultimately leading to improved patient outcomes and more effective clinical management. ⁽⁵⁾.

Age and sex distribution: The analysis of age and sex distribution reveals a notable concentration of individuals aged between 41 to 50 years, comprising 40% of the total population studied. This finding indicates a relatively even distribution across middle-aged groups, with a noticeable decrease in representation within both younger and older age categories. Regarding sex distribution, there is an equal split between males and females, with each gender accounting for 50% of the total population under study. This balanced distribution highlights an absence of gender bias within the sample and provides a comprehensive perspective on age and sex demographics within the studied cohort.

 In essence, the data underscores a significant presence of middle-aged individuals, particularly in the 41 to 50 age range, alongside an equitable distribution between males and females. These insights contribute to a comprehensive understanding of the age and sex demographics within the research cohort, shedding light on important population trends and characteristics.

Complaints: "Headache" emerges as the most prevalent complaint, constituting 42.5% of the total count, followed by "Headache and Giddiness" at 15.0%. Notably, combinations such as "Headache and Vomiting" and "Headache and Giddiness" represent significant proportions of the dataset, collectively contributing to 27.5% of the total complaints. Aneurysmal SAH often manifests as a sudden and intense headache, often referred to as the "most severe headache I have ever experienced". It is necessary to assess all patients with this type of headache, commonly known as a "thunderclap headache", for subarachnoid hemorrhage (SAH). Headache is frequently a solitary manifestation. Three extensive consecutive trials, involving a total of 5283 patients, discovered that 329 individuals (6 per cent) with a severe-onset headache reaching its peak within one hour had subarachnoid haemorrhage (SAH) ^(6,7,8).

NECT with Non-Traumatic SAH: All cases devoid of any history of trauma but showing signs of subarachnoid hemorrhage (SAH) in non-enhanced CT scans (NECT) were included in this study. The sensitivity of an NCCT scan conducted within 24 hours surpasses 95% in detecting subarachnoid haemorrhages. Blood, which appears as a signal with high density, is typically detected in the cisterns surrounding the brainstem and the basal cisterns. This characteristic observation aids in the identification of SAH during diagnostic imaging procedures. ⁽⁹⁾.

CT Angiography:  The diagnoses within the study reveal "Aneurysm" as the predominant finding, encompassing 80.0% of the total cases analysed. The remaining 20.0% of cases are attributed to "AVM" (Arteriovenous Malformation). An interesting observation is that "Aneurysm" constitutes the entire cumulative percentage, indicating its complete prevalence within the dataset. This significant prevalence of "Aneurysm" underscores its importance as the primary diagnosis encountered in the study. Conversely, "AVM" represents a smaller yet noteworthy portion of the cases, highlighting the diversity of vascular abnormalities encountered in clinical practice. The distinct distribution of these diagnoses sheds light on the spectrum of vascular pathologies encountered in patients undergoing diagnostic evaluations.

Site of lesion: The analysis of site prevalence reveals that the Anterior Communicating Artery (ACOM) is the most frequently affected, accounting for 35% of cases. Other sites exhibit lower frequencies in comparison. Notable observations include the presence of Arteriovenous Malformations (AVMs) in diverse regions such as the frontal, parietal, and temporal lobes, each contributing 2.5% to the total count. Furthermore, specific arteries like the Basilar artery and segments of the Middle Cerebral Artery (MCA) and Anterior Cerebral Artery (ACA) are identified within the dataset. This distribution of affected sites provides insights into the anatomical distribution of vascular abnormalities. The prominence of the ACOM in terms of prevalence underscores its clinical significance in vascular pathology. Meanwhile, the presence of AVMs in various cerebral regions highlights the diverse nature of vascular malformations encountered in clinical practice. Additionally, the identification of specific arteries further enriches our knowledge of the localization of vascular abnormalities within the cerebral vasculature.

Presence of Aneurysm: Within the cases examined, an overwhelming majority, specifically 80.0%, exhibit the presence of aneurysms, highlighting a notable prevalence of this vascular anomaly within the dataset. Conversely, 20.0% of cases indicate the absence of aneurysms, underscoring the diversity of findings encountered in clinical assessments. This substantial prevalence of aneurysms observed in the dataset accentuates their clinical significance and relevance in vascular pathology. The clear predominance of aneurysms among the cases studied emphasizes the importance of thorough diagnostic evaluations and management strategies tailored to address this prevalent vascular abnormality.

Number of aneurysms: In terms of the number of aneurysms detected, the data reveals that the majority of cases, specifically 75.0%, display a solitary aneurysm. A smaller proportion, constituting 2.5% of cases, exhibit either two or three aneurysms. Notably, 20.0% of cases show no presence of aneurysms, highlighting the diversity of findings within the dataset. This distribution of the number of aneurysms underscores the varying degrees of vascular pathology encountered in clinical assessments. The prevalence of single aneurysms indicates a common presentation, while the presence of multiple aneurysms in a subset of cases demonstrates the complexity and potential severity of vascular abnormalities.

Aneurysms site: Among the identified aneurysms, the Anterior Communicating Artery (ACOM) emerges as the most common site, accounting for 45.71% of cases. Following closely behind is the Middle Cerebral Artery (MCA), representing 11.43% of cases. Other notable sites include the Posterior Inferior Cerebellar Artery (PICA), Posterior Communicating Artery (PCOM), and Anterior Cerebral Artery (ACA), each comprising smaller proportions within the dataset. This distribution of aneurysm sites provides insights into the anatomical localization of vascular abnormalities encountered in clinical practice. The prominence of the ACOM and MCA sites underscores their clinical significance and the potential impact on patient management and treatment decisions. Furthermore, the identification of aneurysms in less common sites such as the PICA, PCOM, and ACA highlights the diversity of vascular pathologies and the importance of comprehensive diagnostic evaluations to accurately characterize and manage these conditions. Understanding the distribution of aneurysm sites contributes to a deeper understanding of the anatomical complexities of vascular abnormalities and guides effective clinical interventions. According to a pooled analysis conducted by Greving et-al. In 2014, the probability of aneurysm rupture was highest in the vertebra-basilar, anterior communicating, and posterior communicating arteries. This conclusion was based on data from 6 prospective cohort studies ⁽¹⁰⁾. 

Distribution of Aneurysms: The distribution of aneurysms reveals a significant majority, comprising 80% of cases, located within the Anterior Circulation. In contrast, a smaller proportion, constituting 20% of cases, is observed in the Posterior Circulation. In a study conducted by Takahashi (2011), it was reported that nearly 90% of aneurysms originate from the anterior circulation, specifically highlighting the prevalence of aneurysms within this vascular territory. Our investigation corroborates these findings, demonstrating a similar distribution where the majority of aneurysms are indeed located in the anterior circulation ⁽¹¹⁾.

Size and aspect ratio of aneurysm: Firstly, the analysis of aneurysm size reveals a mean diameter of 4.39 millimetres, with a standard deviation of 2.363. This indicates moderate variability in the sizes of aneurysms within the dataset, which range from a minimum of 1.400 mm to a maximum of 13.30 mm. These findings further support the efficacy of CT angiography in detecting small cerebral aneurysms in routine clinical settings. Our results align with numerous previous studies, reinforcing the reliability and accuracy of CT angiography in identifying and characterizing cerebral aneurysms ^(12,13). Several studies have shown that CT angiography tends to have reduced sensitivity when it comes to detecting tiny aneurysms, mainly those measuring less than 3 mm in size ⁽¹⁴⁾. This limitation has been a significant concern in the accurate diagnosis of small aneurysms.

Classification and Description of Aneurysm Sizes (mm): Notably, the majority of aneurysms in this study fall within the very small size range, measuring less than 3 millimetres. This category constitutes 40.0% of the total aneurysms identified. This significant proportion underscores the prevalence of very small aneurysms within the patient population.

Classification of aspect ratio: The classification of aneurysms based on their aspect ratios reveals that the majority, comprising 60.0% of the total count, fall into the category of an aspect ratio greater than or equal to 1.3. This indicates a significant proportion of aneurysms with a relatively elongated shape. Conversely, 40.0% of aneurysms have an aspect ratio of less than 1.3. These aneurysms tend to have a more rounded shape, which is less frequently associated with higher risks of rupture. In their 2014 study, Daan Backes et al. found that irregularly shaped aneurysms and those with an aspect ratio greater than 1.3 are linked to an increased risk of the rupture of the aneurysm. This correlation holds regardless of the aneurysm's size, location, or the characteristics of the patient. The findings by Backes et al. underscore the importance of aspect ratio as a critical factor in assessing the rupture risk of aneurysms ⁽¹⁵⁾.

Frequencies of Presence of AVM: Arteriovenous malformations (AVM) were identified in a small subset of participants in our study. Specifically, AVMs were present in only 8 participants, which constitutes 20% of the total sample size. This finding indicates that AVMs are relatively uncommon among the study population. Conversely, the majority of participants in our study, totalling 32 individuals, did not have any AVMs. This accounts for 80% of the participants, highlighting a significant prevalence of cases without AVMs.

Site of AVM:  In our study, the occurrence of arteriovenous malformations (AVMs) is evenly distributed across various sites, with each site representing 12.5% of the total count. The specific sites of AVM occurrence include the Left Frontal Lobe, Left Para-sagittal Frontal Lobe, Left Parietal-Lobe, left frontal lobe, Parafalcine Region of Left Frontal Lobe, Right frontal lobe, Right temporal lobe, and Suprasellar Region. This equal representation highlights the diverse anatomical locations where AVMs can manifest. A study conducted by Abla et al.⁽¹⁶⁾ provided additional insights into the outcomes associated with different AVM locations. Their research shows that patients with posterior fossa AVMs are more likely to experience catastrophic outcomes compared to those with supratentorial AVMs. This finding underscores the heightened risk associated with posterior fossa AVMs and the critical need for careful monitoring and management of these cases.

Size of Nidus (cm): In our study, the size of the nidus in arteriovenous malformations (AVMs) is distributed across various categories, each represented by one occurrence. Each size category contributes equally to 12.5% of the total count. The sizes of the nidus range from 0.8 cm to 2.1 cm, with specific increments including 0.9 cm, 1.2 cm, 1.5 cm, 1.6 cm, 1 cm, and 0.6 cm. This range of sizes highlights the variability in nidus dimensions among the AVMs observed in our dataset.

Spetzler-Martin grading: In evaluating arteriovenous malformations (AVMs) using the Spetzler-Martin grading system, we noted distinct categorizations among the cases studied. The majority of cases, constituting 87.5% of the total count, were classified as Grade 1. This classification signifies smaller AVMs with characteristics deemed favourable for surgical intervention. Such cases typically present lower risks and complexities during surgical procedures. Conversely, only one case, representing 12.5% of the total count, fell into Grade 2. This classification indicates larger AVMs with more features that may pose challenges during surgical treatment. High-grade AVMs are linked with higher risks and complexities, necessitating careful consideration and planning for surgical intervention. The Spetzler-Martin grading scale serves as a crucial tool for assessing the risk level associated with surgically removing an AVM. Higher grades on this scale indicate an increased likelihood of encountering surgical complications and potential mortality ⁽¹⁷⁾. Our findings highlight the importance of stratifying AVM cases based on this grading system to guide clinical decision-making and optimize patient outcomes.

CTA and MRA serve as non-invasive diagnostic tools that hold significant value in both screening and preoperative preparations for various medical conditions. These procedures do not require invasive methods, making them preferable options for patients. Specifically, computed tomography angiography (CTA) has demonstrated high sensitivity in detecting ruptured aneurysms, with digital subtraction angiography (DSA) serving as the reference standard, showcasing sensitivity rates ranging from 83% to 98% ⁽¹⁸⁾.

A separate systematic review and meta-analysis, specifically targeting individuals with subarachnoid hemorrhage (SAH), yielded similar outcomes ⁽¹⁹⁾. These findings collectively underscore the importance of leveraging advanced imaging techniques, such as multidetector CTA, in enhancing diagnostic capabilities and improving patient outcomes, especially in cases involving intracranial aneurysms and SAH.

The research indicated that CT angiography showed a fairly high degree of diagnostic precision in identifying small cerebral aneurysms with diameters less than 3 mm. The research points out that the leading non-traumatic cause of subarachnoid hemorrhage (SAH) is aneurysms, with arteriovenous malformations (AVMs) coming in a close second. In particular, aneurysms in the anterior circulation are found to be the most common, with the anterior communicating artery (ACOM) aneurysm being the most frequent subtype. The progress in medical imaging technologies, such as the utilization of multislice detector CT scans, has greatly improved our capability to detect aneurysms, even those measuring 3 mm or smaller. This advancement in imaging not only facilitates diagnosis but also emphasizes the significance of early detection and treatment in the management of SAH, especially concerning aneurysms of diverse sizes and positions within the cerebral vasculature. 

Multi-Detector Computed Tomography Angiography (MDCTA) plays a crucial role in illustrating the structure and imaging features of vascular lesions. It offers thorough evaluations of cerebral aneurysms and arteriovenous malformations, assisting in assessing their size, location, structure, rupture status, and unique imaging traits, which are vital for planning endovascular or surgical interventions. The sophisticated multiplanar reconstruction abilities of MDCT improve diagnostic accuracy, making it an invaluable resource for addressing intricate clinical situations encountered in imaging studies.

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